This document provides an introduction and overview of the immune system. It discusses that the immune system consists of innate and adaptive immunity. The innate immune system is the first line of defense and includes physical barriers like skin and secretions, as well as cellular components in the blood like white blood cells, complement proteins, and cytokines. When pathogens breach these barriers, the innate immune cells like neutrophils, macrophages, and natural killer cells work to eliminate pathogens through mechanisms like phagocytosis, cytokine signaling, and inflammation. The adaptive immune system provides a secondary defense through antigen-specific responses like antibodies and T-cells.
Antigens are substances that induce an immune response when introduced to a host. They have two key characteristics - immunogenicity, which is the ability to stimulate an immune response, and antigenicity, which is the ability to react with antibodies or sensitized T cells. Antigens can be classified as foreign, auto, iso, or hetero antigens depending on their source. Important antigen types include haptens, epitopes, and superantigens. The immune system responds to antigens through antibodies and T cell activation.
This document provides an introduction to immunology and the immune system. It discusses the study of immunology and defines the immune system. It also describes the innate and adaptive immune responses, natural and artificial immunity, the roles of antibodies and lymphocytes in humoral and cell-mediated immunity, and the functions of the lymphatic system. Key cell types like phagocytes, B cells, T cells, and antigens are also introduced.
The document discusses immuno-oncology and the relationship between cancer and the immune system. It provides an overview of topics that will be covered in an upcoming webinar, including advances in immuno-oncology for different cancer types and combination immunotherapy approaches. The document then reviews key topics in more depth, including how immuno-oncology focuses on improving the body's immune response against cancer and recent immunotherapy approvals. It also discusses how cancer can evade the immune system and strategies for cancer immunotherapy, such as manipulating co-stimulatory signals, enhancing antigen presenting cells, and using cytokines, monoclonal antibodies, and cancer vaccines.
Bcell activation , differentiation and memory AkshitaMengi12
This document discusses B cell activation, differentiation, and memory. It defines B cells as lymphocytes involved in humoral immunity that develop in the bone marrow and express B cell receptors on their surface. Upon activation in secondary lymphoid organs by antigen binding, B cells can differentiate into plasma cells that secrete antibodies or memory B cells. Differentiation requires T cell-dependent or T cell-independent activation pathways and involves biochemical signaling events. The document also describes the various cell types that B cells can differentiate into and the role of memory B cells in recall responses.
The immune system has two main lines of defense - innate (non-specific) and adaptive (specific). The innate system provides immediate protection and involves physical and chemical barriers like skin and stomach acid. If pathogens breach these barriers, the second line uses phagocytes, natural killer cells, and inflammation to attack invaders. The adaptive system has a delayed but stronger response that involves lymphocytes. It distinguishes self from non-self and has immunological memory, providing lifelong protection against reinfection.
The immune system consists of cells, proteins, and lymphoid organs that work together to protect the body from infection. The immune system has two branches: innate immunity provides a general and immediate response, while adaptive immunity provides a tailored response after initial exposure. Innate immunity involves physical barriers and cells like macrophages that recognize pathogens. Adaptive immunity involves B and T cells that recognize specific pathogens and mount stronger responses upon reexposure. Cytokines are proteins that regulate immune cell growth and activation and mediate inflammatory responses.
This document outlines six main mechanisms of autoimmunity:
1) Antigens being released from normally hidden locations in the body and stimulating an immune response.
2) Molecular changes generating new epitopes on normal proteins that are recognized as foreign.
3) Molecular mimicry where infectious agents share epitopes with self-antigens, triggering cross-reactivity.
4) Alterations in antigen processing that fail to induce tolerance or improve antigen presentation.
5) Infections that dysregulate the immune system through polyclonal activation or altered self-antigens.
6) Genetic factors like MHC genes that control antigen presentation and tolerance development impact autoimmunity risk.
This document discusses immunosurveillance and immunotherapy for cancer treatment. It explains that the immune system normally surveils and destroys mutated cells to prevent tumor development, but tumors can evade this response through various mechanisms such as antigen shedding or fast proliferation. Immunotherapy aims to boost the immune system's ability to fight cancer, for example through monoclonal antibodies, non-specific stimulants, cancer vaccines, or T-cell therapies.
Antigens are substances that induce an immune response when introduced to a host. They have two key characteristics - immunogenicity, which is the ability to stimulate an immune response, and antigenicity, which is the ability to react with antibodies or sensitized T cells. Antigens can be classified as foreign, auto, iso, or hetero antigens depending on their source. Important antigen types include haptens, epitopes, and superantigens. The immune system responds to antigens through antibodies and T cell activation.
This document provides an introduction to immunology and the immune system. It discusses the study of immunology and defines the immune system. It also describes the innate and adaptive immune responses, natural and artificial immunity, the roles of antibodies and lymphocytes in humoral and cell-mediated immunity, and the functions of the lymphatic system. Key cell types like phagocytes, B cells, T cells, and antigens are also introduced.
The document discusses immuno-oncology and the relationship between cancer and the immune system. It provides an overview of topics that will be covered in an upcoming webinar, including advances in immuno-oncology for different cancer types and combination immunotherapy approaches. The document then reviews key topics in more depth, including how immuno-oncology focuses on improving the body's immune response against cancer and recent immunotherapy approvals. It also discusses how cancer can evade the immune system and strategies for cancer immunotherapy, such as manipulating co-stimulatory signals, enhancing antigen presenting cells, and using cytokines, monoclonal antibodies, and cancer vaccines.
Bcell activation , differentiation and memory AkshitaMengi12
This document discusses B cell activation, differentiation, and memory. It defines B cells as lymphocytes involved in humoral immunity that develop in the bone marrow and express B cell receptors on their surface. Upon activation in secondary lymphoid organs by antigen binding, B cells can differentiate into plasma cells that secrete antibodies or memory B cells. Differentiation requires T cell-dependent or T cell-independent activation pathways and involves biochemical signaling events. The document also describes the various cell types that B cells can differentiate into and the role of memory B cells in recall responses.
The immune system has two main lines of defense - innate (non-specific) and adaptive (specific). The innate system provides immediate protection and involves physical and chemical barriers like skin and stomach acid. If pathogens breach these barriers, the second line uses phagocytes, natural killer cells, and inflammation to attack invaders. The adaptive system has a delayed but stronger response that involves lymphocytes. It distinguishes self from non-self and has immunological memory, providing lifelong protection against reinfection.
The immune system consists of cells, proteins, and lymphoid organs that work together to protect the body from infection. The immune system has two branches: innate immunity provides a general and immediate response, while adaptive immunity provides a tailored response after initial exposure. Innate immunity involves physical barriers and cells like macrophages that recognize pathogens. Adaptive immunity involves B and T cells that recognize specific pathogens and mount stronger responses upon reexposure. Cytokines are proteins that regulate immune cell growth and activation and mediate inflammatory responses.
This document outlines six main mechanisms of autoimmunity:
1) Antigens being released from normally hidden locations in the body and stimulating an immune response.
2) Molecular changes generating new epitopes on normal proteins that are recognized as foreign.
3) Molecular mimicry where infectious agents share epitopes with self-antigens, triggering cross-reactivity.
4) Alterations in antigen processing that fail to induce tolerance or improve antigen presentation.
5) Infections that dysregulate the immune system through polyclonal activation or altered self-antigens.
6) Genetic factors like MHC genes that control antigen presentation and tolerance development impact autoimmunity risk.
This document discusses immunosurveillance and immunotherapy for cancer treatment. It explains that the immune system normally surveils and destroys mutated cells to prevent tumor development, but tumors can evade this response through various mechanisms such as antigen shedding or fast proliferation. Immunotherapy aims to boost the immune system's ability to fight cancer, for example through monoclonal antibodies, non-specific stimulants, cancer vaccines, or T-cell therapies.
introduction of adaptive immunity. classification of adaptive immunity, factor affecting it and mechanism of adaptive immunity comparison between adaptive immunity and innate immunity. characteristic of adaptive immunity . cell mediated immune responses immunoglobulins
types of immunoglobulins. functions of immunoglobulins, hypersensitivity reactions
This document provides an overview of basic immunology. It begins with an introduction to immunity, the immune system, and immunology. It then discusses the history of immunology, types of immunity including innate and acquired immunity. It describes the tissues and cells involved in immunity. It covers basic aspects like antigens, antibodies, antigen-antibody reactions, and the complement system. It also discusses major histocompatibility complex, cytokines, immune disorders, and immune responses in periodontal pathogenesis.
This document discusses immunoglobulins and the antigen-antibody interaction. It describes the basic structure and classes of immunoglobulins including IgG, IgA, IgM, IgD and IgE. Immunoglobulins are glycoproteins produced in response to antigens that have properties like molecular weight and half-life that vary by class. The interaction between antigens and antibodies is also summarized, noting characteristics like specificity, binding sites and forces. Methods for detecting antigen-antibody reactions include precipitation, agglutination, radioimmunoassay, ELISA and complement fixation.
The document summarizes key principles of the adaptive immune response. It describes how adaptive immunity arose due to limitations of innate immunity, including lack of specificity and memory. The adaptive response involves T and B lymphocytes that recognize specific antigens through cell surface receptors. Activation of T and B cells requires recognition of antigen along with costimulatory signals. This leads to clonal expansion and generation of effector cells and immunological memory. Adaptive immunity allows for tailored, amplified responses with self/non-self discrimination and immunological memory.
1) Clonal selection theory states that when a B cell encounters its specific antigen, it is activated to multiply and produce clones that secrete antibodies against that antigen.
2) Effector cells like plasma cells and activated T cells carry out immune responses by secreting antibodies or performing cell-mediated responses.
3) Memory cells are also produced and provide faster secondary immune responses upon reexposure to the same antigen.
This document summarizes the key components and steps of the immune response. It describes the main cellular components of the immune system including T cells, B cells, natural killer cells, monocytes, macrophages, dendritic cells, and other granular leukocytes. It also discusses immunoglobulins, antigen presentation, opsonization, phagocytosis, and the complement system. The immune response involves recognition of pathogens by immune cells, activation and proliferation of responsive cells, and elimination of the pathogen through actions like phagocytosis, antibody production, and induction of cell death.
This document discusses T cell activation and maturation. It describes the processes of negative and positive selection that screen T cells. T cell activation occurs through engagement of the T cell receptor and co-stimulatory molecules by MHC peptide and co-stimulatory molecules on antigen presenting cells. Binding of the T cell receptor provides the first signal, while co-stimulation provides the second signal required for an effective immune response.
This document discusses the B cell receptor (BCR) and its role in chronic lymphocytic leukemia (CLL). The BCR is composed of immunoglobulin and Igα/Igβ proteins that transmit signals into cells. CLL results when too many B cells become abnormal lymphocytes. In CLL, tonic BCR signaling provides growth signals and plays a key role in disease progression. New drugs target proteins in the BCR pathway like Btk and Syk to block this signaling and stop cancer cell growth and division. Ibrutinib is an approved treatment that inhibits the BCR complex and brings hope to CLL patients.
The document summarizes key aspects of the immune system, including immunoglobulins, cytokines, and the complement system. It describes:
1) Immunoglobulins (antibodies) are Y-shaped proteins produced by B cells that bind to antigens with high specificity. The five major classes in humans are IgG, IgA, IgM, IgE, and IgD.
2) Cytokines are signaling proteins like interleukins and interferons that are produced by immune cells and regulate immune responses. They activate and attract immune cells.
3) The complement system is a group of proteins that promote inflammation and mark pathogens for destruction. It consists of over 35 proteins and operates through classical
This document provides an overview of antigen-antibody reactions, including definitions, general features, measurement techniques, types of reactions such as precipitation, agglutination, neutralization, immunofluorescence, radioimmunoassay, and enzyme-linked immunosorbent assay (ELISA). It describes techniques like precipitation reactions in liquids and gels, single and double diffusion, electrophoresis, latex agglutination, complement fixation, and microtitration agglutination tests. The document outlines the applications and uses of these various antigen-antibody reaction techniques.
Type I, II, III, and IV hypersensitivity reactions are classified based on their pathogenic mechanisms. Type I reactions involve IgE antibodies and mast cell degranulation. Type II reactions involve IgG or IgM antibodies binding to cell surfaces and activating complement. Type III reactions involve immune complex deposition in tissues. Type IV reactions are T cell-mediated and occur hours to days after antigen exposure. Examples of each type are discussed.
This document discusses cytokines, which are proteins that mediate and regulate the immune system. Some key points:
- Cytokines are produced by multiple cell types and act on multiple cell types in redundant and pleiotropic ways. Their secretion is brief and self-limited.
- They have general functions like mediating innate immunity, regulating lymphocyte growth/activation/differentiation, and activating inflammatory cells or stimulating hematopoiesis.
- Th17 and Treg cells are discussed - Th17 promotes inflammation while Treg prevents effector T cell development and function.
- Cytokine expression and activity are regulated by chromatin structure alterations and the SOCS/CIS family, which inhibit JAK activity or compete
This document defines key terms related to antigens and the immune response. It discusses how antigens stimulate an immune response by interacting with antibodies and T cells. There are different types of antigens including exogenous antigens that enter the body from outside, endogenous antigens generated inside cells, autoantigens that are recognized by the immune system in autoimmune diseases, and tumor antigens expressed by cancer cells. The document also describes properties of antigens like immunogenicity and antigenicity, and characteristics of antigenic epitopes recognized by B cells and T cells. It classifies antigens as thymus-dependent or -independent and discusses conventional antigens, superantigens, and adjuvants that enhance immune responses.
This document provides an overview of hypersensitivity and its classification. It discusses the four main types of hypersensitivity: Type I is anaphylactic and mediated by IgE antibodies, examples include anaphylaxis and atopy. Type II involves IgG antibodies causing blood transfusion reactions, hemolytic disease of newborn, and drug-induced hemolysis. Type III hypersensitivity involves immune complex deposition that can cause localized or generalized tissue damage. Type IV is cell-mediated and causes delayed reactions like tuberculin reactions and contact dermatitis. It provides details on the mechanisms, features, and examples of each type of hypersensitivity reaction.
1. Innate immunity provides the first line of defense against pathogens and includes anatomical barriers, inflammation, phagocytosis, and antimicrobial proteins/peptides.
2. Adaptive immunity develops over time upon exposure to specific pathogens and provides enhanced protection through antibody production and immunological memory.
3. The major categories of innate immunity defenses are anatomical barriers, inflammation, phagocytosis, microbial antagonism by normal flora, and antimicrobial substances in tissues. Adaptive immunity involves B cells, T cells, and production of antibodies.
The document summarizes key concepts in immunology, including:
1) It defines innate and adaptive immunity, and the types of natural, acquired, active, and passive immunity.
2) It describes the cells of the immune system including B cells, T cells, macrophages, and natural killer cells.
3) It discusses antibodies, cytokines, and how the immune system can fail to distinguish self from non-self, leading to autoimmune diseases.
Autoimmunity is caused by the immune system attacking the body's own tissues and organs. Around 5-7% of adults are affected by autoimmune diseases, which are more common in women. Left-handed individuals have a higher risk of autoimmunity. Mechanisms that can trigger autoimmunity include molecular mimicry between foreign and self-antigens, genetic factors that influence antigen presentation, and infections that dysregulate the immune response. Treatment options aim to suppress the immune system or remove autoantibodies.
Antibodies are immune system-related proteins called immunoglobulins. Each antibody consists of four polypeptides– two heavy chains and two light chains joined to form a "Y" shaped molecule. ... This variable region, composed of 110-130 amino acids, give the antibody its specificity for binding antigen.
Here is some information about 5 important immunological techniques including Flowcytometry and RIA
I hope it helps and please comment if u come across any mistakes or scope for improvement, it'll really be appreciated.
The innate immune system provides the first line of defense against pathogens. It includes physical barriers like skin and mucous membranes, secretions containing antibodies, and immune cells like neutrophils, monocytes, macrophages, and natural killer cells that attack pathogens. When pathogens breach these defenses, internal responses are triggered, including cytokines that signal immune cells, complement proteins that coat pathogens, and coagulation factors that cause clotting. This activates inflammation, which causes swelling, redness, heat, and pain to isolate and destroy the pathogen. Together these innate responses provide rapid, non-specific protection against a wide range of microbes.
introduction of adaptive immunity. classification of adaptive immunity, factor affecting it and mechanism of adaptive immunity comparison between adaptive immunity and innate immunity. characteristic of adaptive immunity . cell mediated immune responses immunoglobulins
types of immunoglobulins. functions of immunoglobulins, hypersensitivity reactions
This document provides an overview of basic immunology. It begins with an introduction to immunity, the immune system, and immunology. It then discusses the history of immunology, types of immunity including innate and acquired immunity. It describes the tissues and cells involved in immunity. It covers basic aspects like antigens, antibodies, antigen-antibody reactions, and the complement system. It also discusses major histocompatibility complex, cytokines, immune disorders, and immune responses in periodontal pathogenesis.
This document discusses immunoglobulins and the antigen-antibody interaction. It describes the basic structure and classes of immunoglobulins including IgG, IgA, IgM, IgD and IgE. Immunoglobulins are glycoproteins produced in response to antigens that have properties like molecular weight and half-life that vary by class. The interaction between antigens and antibodies is also summarized, noting characteristics like specificity, binding sites and forces. Methods for detecting antigen-antibody reactions include precipitation, agglutination, radioimmunoassay, ELISA and complement fixation.
The document summarizes key principles of the adaptive immune response. It describes how adaptive immunity arose due to limitations of innate immunity, including lack of specificity and memory. The adaptive response involves T and B lymphocytes that recognize specific antigens through cell surface receptors. Activation of T and B cells requires recognition of antigen along with costimulatory signals. This leads to clonal expansion and generation of effector cells and immunological memory. Adaptive immunity allows for tailored, amplified responses with self/non-self discrimination and immunological memory.
1) Clonal selection theory states that when a B cell encounters its specific antigen, it is activated to multiply and produce clones that secrete antibodies against that antigen.
2) Effector cells like plasma cells and activated T cells carry out immune responses by secreting antibodies or performing cell-mediated responses.
3) Memory cells are also produced and provide faster secondary immune responses upon reexposure to the same antigen.
This document summarizes the key components and steps of the immune response. It describes the main cellular components of the immune system including T cells, B cells, natural killer cells, monocytes, macrophages, dendritic cells, and other granular leukocytes. It also discusses immunoglobulins, antigen presentation, opsonization, phagocytosis, and the complement system. The immune response involves recognition of pathogens by immune cells, activation and proliferation of responsive cells, and elimination of the pathogen through actions like phagocytosis, antibody production, and induction of cell death.
This document discusses T cell activation and maturation. It describes the processes of negative and positive selection that screen T cells. T cell activation occurs through engagement of the T cell receptor and co-stimulatory molecules by MHC peptide and co-stimulatory molecules on antigen presenting cells. Binding of the T cell receptor provides the first signal, while co-stimulation provides the second signal required for an effective immune response.
This document discusses the B cell receptor (BCR) and its role in chronic lymphocytic leukemia (CLL). The BCR is composed of immunoglobulin and Igα/Igβ proteins that transmit signals into cells. CLL results when too many B cells become abnormal lymphocytes. In CLL, tonic BCR signaling provides growth signals and plays a key role in disease progression. New drugs target proteins in the BCR pathway like Btk and Syk to block this signaling and stop cancer cell growth and division. Ibrutinib is an approved treatment that inhibits the BCR complex and brings hope to CLL patients.
The document summarizes key aspects of the immune system, including immunoglobulins, cytokines, and the complement system. It describes:
1) Immunoglobulins (antibodies) are Y-shaped proteins produced by B cells that bind to antigens with high specificity. The five major classes in humans are IgG, IgA, IgM, IgE, and IgD.
2) Cytokines are signaling proteins like interleukins and interferons that are produced by immune cells and regulate immune responses. They activate and attract immune cells.
3) The complement system is a group of proteins that promote inflammation and mark pathogens for destruction. It consists of over 35 proteins and operates through classical
This document provides an overview of antigen-antibody reactions, including definitions, general features, measurement techniques, types of reactions such as precipitation, agglutination, neutralization, immunofluorescence, radioimmunoassay, and enzyme-linked immunosorbent assay (ELISA). It describes techniques like precipitation reactions in liquids and gels, single and double diffusion, electrophoresis, latex agglutination, complement fixation, and microtitration agglutination tests. The document outlines the applications and uses of these various antigen-antibody reaction techniques.
Type I, II, III, and IV hypersensitivity reactions are classified based on their pathogenic mechanisms. Type I reactions involve IgE antibodies and mast cell degranulation. Type II reactions involve IgG or IgM antibodies binding to cell surfaces and activating complement. Type III reactions involve immune complex deposition in tissues. Type IV reactions are T cell-mediated and occur hours to days after antigen exposure. Examples of each type are discussed.
This document discusses cytokines, which are proteins that mediate and regulate the immune system. Some key points:
- Cytokines are produced by multiple cell types and act on multiple cell types in redundant and pleiotropic ways. Their secretion is brief and self-limited.
- They have general functions like mediating innate immunity, regulating lymphocyte growth/activation/differentiation, and activating inflammatory cells or stimulating hematopoiesis.
- Th17 and Treg cells are discussed - Th17 promotes inflammation while Treg prevents effector T cell development and function.
- Cytokine expression and activity are regulated by chromatin structure alterations and the SOCS/CIS family, which inhibit JAK activity or compete
This document defines key terms related to antigens and the immune response. It discusses how antigens stimulate an immune response by interacting with antibodies and T cells. There are different types of antigens including exogenous antigens that enter the body from outside, endogenous antigens generated inside cells, autoantigens that are recognized by the immune system in autoimmune diseases, and tumor antigens expressed by cancer cells. The document also describes properties of antigens like immunogenicity and antigenicity, and characteristics of antigenic epitopes recognized by B cells and T cells. It classifies antigens as thymus-dependent or -independent and discusses conventional antigens, superantigens, and adjuvants that enhance immune responses.
This document provides an overview of hypersensitivity and its classification. It discusses the four main types of hypersensitivity: Type I is anaphylactic and mediated by IgE antibodies, examples include anaphylaxis and atopy. Type II involves IgG antibodies causing blood transfusion reactions, hemolytic disease of newborn, and drug-induced hemolysis. Type III hypersensitivity involves immune complex deposition that can cause localized or generalized tissue damage. Type IV is cell-mediated and causes delayed reactions like tuberculin reactions and contact dermatitis. It provides details on the mechanisms, features, and examples of each type of hypersensitivity reaction.
1. Innate immunity provides the first line of defense against pathogens and includes anatomical barriers, inflammation, phagocytosis, and antimicrobial proteins/peptides.
2. Adaptive immunity develops over time upon exposure to specific pathogens and provides enhanced protection through antibody production and immunological memory.
3. The major categories of innate immunity defenses are anatomical barriers, inflammation, phagocytosis, microbial antagonism by normal flora, and antimicrobial substances in tissues. Adaptive immunity involves B cells, T cells, and production of antibodies.
The document summarizes key concepts in immunology, including:
1) It defines innate and adaptive immunity, and the types of natural, acquired, active, and passive immunity.
2) It describes the cells of the immune system including B cells, T cells, macrophages, and natural killer cells.
3) It discusses antibodies, cytokines, and how the immune system can fail to distinguish self from non-self, leading to autoimmune diseases.
Autoimmunity is caused by the immune system attacking the body's own tissues and organs. Around 5-7% of adults are affected by autoimmune diseases, which are more common in women. Left-handed individuals have a higher risk of autoimmunity. Mechanisms that can trigger autoimmunity include molecular mimicry between foreign and self-antigens, genetic factors that influence antigen presentation, and infections that dysregulate the immune response. Treatment options aim to suppress the immune system or remove autoantibodies.
Antibodies are immune system-related proteins called immunoglobulins. Each antibody consists of four polypeptides– two heavy chains and two light chains joined to form a "Y" shaped molecule. ... This variable region, composed of 110-130 amino acids, give the antibody its specificity for binding antigen.
Here is some information about 5 important immunological techniques including Flowcytometry and RIA
I hope it helps and please comment if u come across any mistakes or scope for improvement, it'll really be appreciated.
The innate immune system provides the first line of defense against pathogens. It includes physical barriers like skin and mucous membranes, secretions containing antibodies, and immune cells like neutrophils, monocytes, macrophages, and natural killer cells that attack pathogens. When pathogens breach these defenses, internal responses are triggered, including cytokines that signal immune cells, complement proteins that coat pathogens, and coagulation factors that cause clotting. This activates inflammation, which causes swelling, redness, heat, and pain to isolate and destroy the pathogen. Together these innate responses provide rapid, non-specific protection against a wide range of microbes.
The immune system has both nonspecific defenses that provide immediate protection against pathogens and specific defenses that develop over time through exposure or vaccination. The specific defenses include B cells and T cells. B cells produce antibodies that identify pathogens for destruction. T cells identify and destroy infected cells. Immunity can be active, developing through natural exposure or vaccination, or passive, providing temporary protection through transfer of antibodies. Vaccines provide active immunity by exposing the immune system to antigens in a controlled way. The immune system defends the body but can also cause allergic reactions and autoimmune diseases when improperly activated.
The document summarizes the principles of immunity and the immune system. It describes the requirements for an immune response, including detecting foreign objects, preventing the host from being killed, limiting replication of foreign objects, and limiting damage. It then outlines the types of infectious agents and describes both innate/nonspecific immunity including anatomical, physiological, inflammatory barriers and cellular and humoral responses as well as adaptive/specific cellular and humoral immunity responses.
Cells of the Immune System 120722.pptx immunologymansidhingra05
The document summarizes key aspects of the immune system. It describes how hematopoietic stem cells give rise to lymphoid and myeloid progenitor cells to form the different cells of the immune system. It then contrasts innate and acquired immunity, outlining their differences. Components of each system are listed. The roles of phagocytosis, opsonization, inflammation, and bridges between the two immunity types are also briefly explained.
The document summarizes key concepts in immunology. It defines the immune system and its main components: organs, cells, and molecules. It describes the roles of innate and adaptive immunity. Innate immunity provides rapid initial response via non-specific mechanisms. Adaptive immunity responds more slowly through antigen-specific T and B cells and develops immunological memory. Primary responses are smaller while secondary responses are larger and longer-lasting due to memory cells. Failure of the immune response can result in hypersensitivity or immunodeficiency.
This document provides an overview of the human immune system and its defenses against disease. It discusses the external barriers of skin and mucus, internal responses like phagocytosis and inflammation, and the adaptive immune system involving B and T cells and antibody production. It covers active and passive immunity, immune responses, antigen recognition, and immune system disorders like autoimmunity, allergy, and AIDS. The immune system provides multilayered defenses that have largely evolved to protect the body from infectious diseases, toxins, and other foreign invaders.
immunity, types,Innate immunity and Adaptive Immunity, primary and secondary immune response, structure and functions of antibodies, immunoglobulins, hypergammaglobulinemia, multiple myeloma, bence jones protein, electrophoretic pattern of multiple myeloma.
Overview of the Immune System: Innate vs. Adaptive Defenses
Innate-Nonspecific Defenses
First Line of defense: Physical barriers
Second Line of defense:
- Major cellular components
Phagocytes
Basophils
Eosinophils
NK cells
- Chemical signals
Interferons
Complement Proteins
Inflammation
Fever (pyrogens)
microbiology and immunology basic immunologymulkiabdiadan
This document provides an overview of basic immunology. It begins with introductions and definitions of key immunology concepts. It then discusses the history of immunology, types of immunity including innate and acquired immunity. It describes the tissues, cells and basic aspects involved in the immune system such as antigens, antibodies and complement system. It also covers major histocompatibility complex, cytokines and disorders of the immune system. The document is intended as a basic introduction and reference for immunology.
The document summarizes the key differences between innate and adaptive immunity. Innate immunity is present from birth and provides non-specific resistance to pathogens. It involves anatomical barriers, phagocytes, complement proteins, cytokines and other cellular components. Adaptive immunity is acquired during life and provides pathogen-specific resistance through T cells, B cells, antibodies, immunological memory and specificity. Dendritic cells, macrophages, complement pathways and cytokines act as bridges between the innate and adaptive immune systems.
The document outlines the objectives and key concepts of innate and adaptive immunity. It discusses:
- The principal cells and tissues of the immune system, including lymphocytes, macrophages, neutrophils, and dendritic cells.
- The differences between innate and adaptive immunity, where innate immunity provides immediate response and adaptive immunity has immunological memory and is antigen-specific.
- How innate immunity involves epithelial barriers, phagocytes, natural killer cells, and plasma proteins while adaptive immunity involves lymphocytes and humoral or cell-mediated responses.
- How lymphocytes recognize antigens through membrane-bound antibodies on B cells or T cell receptors that recognize antigen peptides bound to MHC molecules.
The immune system distinguishes self from non-self to protect the body from infection and tissue damage. It has both innate and adaptive responses. The innate system provides early defense through physical barriers, chemicals, and phagocytes. The adaptive system has lymphocytes that provide specific and long-lasting immunity through antibodies and memory. The immune system is organized with primary organs like the bone marrow and thymus that produce cells, and secondary organs like lymph nodes and spleen where immune responses occur.
The immune system distinguishes self from non-self to protect the body from infection and tissue damage. It has both innate and adaptive responses. The innate system provides early defense through physical barriers, chemicals, and phagocytes. The adaptive system has lymphocytes that provide specific and long-lasting immunity through antibodies and memory. The immune system is organized with primary organs like the bone marrow and thymus that produce cells, and secondary organs like lymph nodes and spleen where immune responses occur.
The innate immune system provides the body's first line of defense against pathogens through physical, chemical, and cellular barriers. It responds quickly but non-specifically. Components of innate immunity include physical barriers like skin, mucous membranes, and microbiota; physiological barriers like low pH and natural killer cells; cellular barriers comprising phagocytes and cytokines; and inflammatory responses. Pattern recognition receptors expressed by innate immune cells recognize pathogen-associated molecular patterns and damage-associated molecular patterns to detect and respond to infections.
Lect 1 introduction to immunology by dr. naeemHassan Ahmad
This document provides an introduction to immunology. It discusses the following key points:
1) Microorganisms are found everywhere and human exposure is inevitable, with 300-400 microbial species known to cause disease.
2) Immunology is the study of protection from foreign substances like viruses and bacteria, as well as the body's response, which includes innate and adaptive immunity.
3) Non-specific immunity provides immediate protection prior to exposure through anatomical barriers, secretory molecules, phagocytes, and other cellular components that help fight infection.
This document provides an overview of immunology and the immune system. It discusses the key topics of innate immunity, adaptive immunity, antigens, antibodies, cells of the immune system, and the anatomy of the lymphoid system. Innate immunity is the non-specific first line of defense and includes physical barriers, chemical factors, cytokines, and cellular components like phagocytes. Adaptive immunity involves antigen-specific B cells and T cells and immunological memory. The primary lymphoid organs are the bone marrow and thymus, where lymphocytes mature. Secondary lymphoid organs include lymph nodes and facilitate immune cell interactions.
Similar to SBL100-Immunology lectures 1-3.pptx (20)
The document discusses DNA packaging in eukaryotic cells. It describes how DNA is wrapped around histone proteins to form nucleosomes, which are regularly spaced beads on a string of chromatin. Nucleosomes further condense into a 30nm fiber through interactions between nucleosomes. Higher-order folding involves loops of fiber and coiling to achieve the extreme compaction needed to fit a cell's full genome inside the nucleus.
This document discusses various methods for classifying bacteria, including morphological, anatomical, staining, cultural, nutritional, and environmental characteristics. Morphologically, bacteria are classified as cocci, bacilli, actinomycetes, spirochaetes, mycoplasmas, or rickettsiae/chlamydiae based on their shape and arrangement. Anatomical features used in classification include presence of capsules, flagella, and ability to form spores. Staining characteristics such as Gram-stain and acid-fast reactions also provide means of classification. Cultural characteristics like growth requirements, hemolysis, carbohydrate utilization, growth rate, and pigment production further differentiate bacterial types. Environmental tolerances
Chromosomal aberrations are structural or numerical changes in chromosomes that can occur due to errors in cell division. There are two main types - numerical abnormalities which change the number of chromosomes like aneuploidy (extra or missing chromosome) and polyploidy (multiple sets of chromosomes), and structural abnormalities which change the chromosome structure like deletions, duplications, inversions, and translocations. Specific chromosomal abnormalities cause genetic syndromes with characteristic physical and developmental features.
Cell division is essential for organism reproduction and involves both mitosis and meiosis. Mitosis produces two identical daughter cells from one parent cell during growth and tissue repair. It has four phases - prophase, metaphase, anaphase and telophase. Meiosis produces gametes like eggs and sperm from a diploid cell and has two rounds. The first round separates homologous chromosomes and the second separates sister chromatids, resulting in four haploid cells.
The document discusses different types of innate animal behaviors. There are two main types: innate behaviors that are determined by an animal's genetics/instincts and do not require learning, such as swimming or migration. The second type are stimulus-driven behaviors that involve an orientation response to some environmental cue. These include tropisms (turning in response to a stimulus), taxes (guided movement toward or away from a stimulus), and nasties (non-directional responses to stimuli). Many examples of different taxes are provided, such as phototaxis, chemotaxis, gravitaxis, which involve responses to light, chemicals, and gravity, respectively.
Behavioral biology is the study of what animals do when interacting with their environment
Behavior can be interpreted in terms of proximate causes (immediate interaction with the environment) or ultimate causes (evolutionary differences)
Animal behaviour
innate behavior - a behavior that is pre-programmed into an organisms genes, no learning is required
learned behavior - a behavior that is not pre-programmed into an organisms genes, learning this behavior is required. However, the ability to learn requires genes.
social behavior - a behavior that includes the interaction between organisms. Can be learned or innate.
Or: Beyond linear.
Abstract: Equivariant neural networks are neural networks that incorporate symmetries. The nonlinear activation functions in these networks result in interesting nonlinear equivariant maps between simple representations, and motivate the key player of this talk: piecewise linear representation theory.
Disclaimer: No one is perfect, so please mind that there might be mistakes and typos.
dtubbenhauer@gmail.com
Corrected slides: dtubbenhauer.com/talks.html
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SBL100-Immunology lectures 1-3.pptx
1. Introduction to the immune
system
Vivekanandan Perumal
vperumal@bioschool.iitd.ac.in
011-26597532
Office hours Wednesday and Friday 5-6pm
2. Immunity
• Immunity is body's ability to resist or eliminate
potentially harmful foreign materials or abnormal
cells
3. History: what imparts Immunity?
• Emil von Behring and Kitasato (1890)
– Serum from vaccinated animals was protective
(diptheria)
• Metchinkoff (1880)
– Cell based Immunity
• Merrill Chase (1940)- Transfer of WBC (immunity to
tuberculosis)
Both serum and cells contribute to immunity
5. The immune system
A functional system – NOT an organ system:
Complex system – includes
• Skin – physical barrier
• Lining of mucus membranes – physical barrier
• Secretions – tears, mucus etc - antimicrobial
• Blood cells and vasculature – WBCs
• Bone marrow
• Liver – makes complement proteins
• Lymphatic system and lymphoid organs
• Most tissues – have resident immune cells
6. Immunity
• Immunity (immunis- Latin-exempt, state of protection
from infectious diseases)
• Immunity is body's ability to resist or eliminate
potentially harmful foreign materials or abnormal cells
• consists of following activities:
– Defense against invading pathogens (viruses & bacteria)
– Removal of 'worn-out' cells (e.g., old RBCs) & tissue debris
(e.g., from injury or disease)
– Identification & destruction of abnormal or mutant cells
(primary defense against cancer)
– Rejection of 'foreign' cells (e.g., organ transplant)
– Inappropriate responses:
• Allergies - response to normally harmless substances
• Autoimmune diseases
8. Overview of the Immune System
Immune System
Innate
(Nonspecific)
1o line of defense
Adaptive
(Specific)
2o line of defense
Interactions between the two systems
9. A typical immune response
INNATE IMMUNITY
Rapid responses to a
broad range of microbes
ACQUIRED IMMUNITY
Slower responses to
specific microbes
External defenses Internal defenses
Skin
Mucous membranes
Secretions
Phagocytic cells
Antimicrobial proteins
Inflammatory response
Natural killer cells
Humoral response
(antibodies)
Cell-mediated response
(cytotoxic
lymphocytes)
Invading
microbes
(pathogens)
Complement
10. Innate immunity vs Adaptive Immunity
No memory
• No time lag
• Not antigen specific
• A lag period
• Antigen specific
• Development
of memory
Innate Immunity
(first line of defense)
Adaptive Immunity
(second line of defense)
11. The innate immune System
Innate Immune
System
External
defenses
Internal
defenses
Interactions between the two systems
14. Anatomical Barriers – Chemical factors
Antimicrobial
Peptides in sweat
Lysozyme in tears /saliva
HCl in stomach
15. Anatomical Barriers – Biological factors
Normal flora – microbes in many parts of the body
Normal flora – competes with pathogens
for nutrients and space
Normal flora – > 1000 species of bacteria
25. Monocytes
• Monocytes (~5% of WBCs)
• Migrate into the tissues and
become Macrophages
Lung Bone
Liver Brain intestine
26. Macrophages
• “Big eaters”
• Phagocytosis of microbes in tissue
(neutrophils are present only in blood)
• Antigen presentation
27. Natural killer cells
• Not B-lymphocytes / T-
lymphocytes
• Important part of the innate
immune system
• Kill virus /bacteria infected
cells (Intracellular
pathogens)
• Kills cancer cells
28. NK cells differentiate choose cells to kill ?
Uninfected cell / Normal cell
Microbe infected cell / cancer cell
Some cell surface proteins are missing
29. How does the killer kill ?
Kills both host cells and microbes
Release of granules with perforins and proteases
30. Toll-like receptors (TLRs)
• Transmembrane proteins
• Present on macrophages / few other cells
• Conserved across vertebrates
• Important part of innate immune system
31. TLRs – What do they do ?
They look out for microbes (or their components)
They bind to the microbes (or their components)
They trigger a cascade of events to kill or protect
against pathogens
THEY ARE INNATE IMMUNE SENSORS
35. What happens when a TLR bind to a microbe ?
TLR binding
to microbe
Inflammation
Secretion of
Cytokines /
Interferon
Phagocytosis
of infected
cell
Apoptosis of
infected cell
36. Summary: innate response – internal
defenses – Cellular (WBCs)
Come into play when the external defenses are breached
• Neutrophils
• Monocytes /macrophages
• NK cells
• TLRs
38. Cytokines
• Small proteins – secreted by
cells of the immune system
• Affect the behaviour of other
cells
• signalling molecules
• Key players in innate and
acquired immunity
39. Which cells release cytokines ?
Cells of the immune system:
• Neutrophils – when they encounter a pathogen
• Macrophages – when they encounter a pathogen
• TLRs – bind to microbe / components of a microbe
• NK cells – on encountering a microbe infected cell /tumour cell
• Lymphocytes – when they are activated
41. Interferons (IFN)
• Signalling proteins produced by by virus infected monocytes
and lymphocytes
• Secreted proteins – Key anti-viral proteins
• “Interfere” with virus replication
• Warn the neighbouring cells that a virus is around...
• If we did not have IFNs – most of us may die of influenza virus
infection
43. 43
The infected cells release IFN
antiviral state
antiviral state
antiviral state
antiviral state
44. 44
Virus infects the neighbouring cells
antiviral state
antiviral state
antiviral state
antiviral state
45. 45
Prewarned cells are able to quickly
inhibit the virus
antiviral state
antiviral state
antiviral state
antiviral state
46. How do interferons inhibit viruses ?
Host protein
Induction
Cascade of events
Virus ds-RNA
Activation
Inactive host protein
Active host protein
Inhibition of
host protein
synthesis
Virus cannot replicate
47. Interleukins
• Interleukins – 1-37
• Not stored inside cells
• Quickly synthesized and secreted in response to infection
• Key modulators of behaviour of immune cells
• Mostly secreted by T-lymphocytes & macrophages
48. What to interleukins do ?
Interleukins
Proliferation of immune cells
Activation of immune cells
Increase antibody production
Inflammation
50. Complement (C`)
• a large number of distinct plasma proteins that react with
one another (C1 thro’ C9)
• Complement can bind to microbes and coat the microbes
• Essential part of innate immune response
• Enhances adaptive immune resposne (taught later)
51. Complement proteins: role in innate
immune system
C`proteins
Inflammation
Facilitates phagocytosis Direct lysis of pathogens
52. How do C` proteins facilitate phagocystosis ?
Bacteria coated with C` Neutrophils have C` receptors
Initiation of phagocytosis
53. How do C` proteins lyse pathogens?
Membrane attack complex formed by c` proteins
54. Coagulation proteins
• Coagulation: mechanism to stop bleeding after injury to blood
vessels
Complex pathway involves
• Platelets
• Coagulation factors
• Vitamin K
56. Coagulation: Delicate balance
Coagulation proteins Anticoagulants
Blood clotting
Inflammation
Apoptosis (prog. Cell death)
Prevent blood clotting
Inhibit inflammation
Inhibit apoptosis
Too much of clotting – Problem
Too little clotting - Problem
Maintenance of a balance
57. Coagulation and innate immunity
Coagulation proteins
Anticoagulants
Pathogens and cytokines
Increased inflammation and increased apoptosis of infected cells
58. Summary: what happens when external defenses fail ?
INNATE IMMUNITY
Rapid responses to a
broad range of microbes
ACQUIRED IMMUNITY
Slower responses to
specific microbes
External defenses Internal defenses
Skin
Mucous membranes
Secretions
Phagocytic cells
Antimicrobial proteins
Inflammatory response
Natural killer cells
Humoral response
(antibodies)
Cell-mediated response
(cytotoxic
lymphocytes)
Invading
microbes
(pathogens)
Complement
62. Inflammation
• Complex biological process by which body responds
to pathogens and irritants
• Associated with swelling of tissue
• Key player in innate immune repsone
63. All roads lead to inflammation
Inflammation
Neutrophils
Monocytes /macrophages
NK cells
TLRs
Cytokines /IFN
C` proteins
Coagulation proteins
Cellular Extracellular
64. Inflammation and vascular changes
• Vasodilatation • Increased capillary permeability
Normal blood vessel Dilated blood vessel
Normal blood vessel
Leaky blood vessel
67. Inflammation and innate immunity
Mast cells – similar to basophils in blood;
mast cells are present in tissues and release histamines in response to wound / infection /irritant
Histamine
Pathogen
removal
Adaptive immune
response
+ + +
68. Summary: role of Inflammation in
innate immunity
• Initiation of phagocytosis – killing of pathogen
• Limiting the spread of infection
• Stimulate adaptive immune response
• Initiate tissue repair
70. The good and bad about inflammation
Acute /short-term -Good chronic /long-term - Bad
71. Chronic inflammation = tissue damage
• Chronic inflammation -
macrophages in the injured
tissue.
• Macrophages release toxins
(including reactive oxygen
species or ROS) that injure
tissues
• chronic inflammation is
almost always accompanied
by tissue destruction.
Normal tissue
Tissue : chronic inflammation
72. Chronic inflammation and tissue
damage
Reduced
tissue
function
Tissue
damage
Chronic
inflammation
Activation of
immune cells
Killing of host cells
75. Immunogens and antigens
• Immunogen / antigen: a substance that elicits
an immune response [i.e. a humoral (antibody
response) or cell-mediated immune response]
Immune response generator
Though the two terms are used interchangeably – there are differences between the two
76. Epitope
• Epitope: the portion of an antigen that is recognized
and bound by an antibody (Ab) or a T-cell receptor
(TCR)
• epitope = antigenic determinant
77. Epitopes
•Epitope: the portion of an antigen that is recognized and bound by an Ab or a T Cell receptor
One protein may have multiple antigenic determinant
79. Immunogenicity
• Immunogencity: is the ability to induce a humoral
(antibody) and/or cell-mediated immune response.
• Weak immunogens
• Strong immunogens
80. What determines immunogenicity ?
• Foreignness: essential for immunogenicity (self-responsive
immune cells are eliminated during lymphocyte development)
• Size: Bigger>Smaller
• Chemical composition: Proteins > nucleic acids /
polysaccharides / lipids
• Structure: Primary /secondary /tertiary structures play a role
• Physical form: Particulate> Soluble
81. Host factors affecting immunogencity
• Difference across species (interspecies)
• Differences within a species (intraspecies)
- Responders / non-responders to vaccine
- differences in disease severity in epidemics
Genetics
Age
82. Isoantigens
• Isoantigens: Antigens present in some but not all
members of a species
• Blood group antigens – basis of blood grouping
• MHC (major histocompatibility complex)- cell surface
glycoproteins
83. Autoantigens
• Autoantigens are substances capable of immunizing
the host from which they are obtained.
• Self antigens are ordinarily non-antigenic
• Modifications of self-antigens are capable of eliciting
an immune response
84. Haptens
• Haptens are small molecules which are non-
immunogenic, thus could never induce an
immune response by themselves.
87. What is an antibody?
• Produced by Plasma cell (B-lymphocytes producing Ab)
• Essential part of adaptive immunity
• Specifically bind a unique antigenic epitope (also called an
antigenic determinant)
• Possesses antigen binding sites
• Members of the class of proteins called immunoglobulins
88. What does an antibody look like ?
• 2 identical heavy chains
• 2 identical light chains
• Each heavy chain – has a
constant and a variable
region
• Each light chain has a
constant and a variable
region
H H
L L
Constant
region
Variable
region
90. Antibody: Fab
Fab region
• Variable region of the
antibody
• Tip of the antibody
• Binds the antigen
• Specificity of antigen
binding determined by
VH and VL
91. Antibody: Fc
Fc region
• Constant region
• Base of the antibody
• Can bind cell receptors
and complement
proteins
92. • Antibodies occur in 2 forms
– Soluble Ag: secreted in blood and tissue
– Membrane-bound Ag: found on surface of B-cell, also
known as a B-cell receptor (BCR)
Antibodies exist in two forms