This document discusses the cells of the immune system that are involved in the host response to periodontal pathogens. It describes the main immune cells, including lymphocytes (B cells, T cells, natural killer cells), phagocytes (neutrophils, macrophages, dendritic cells), mast cells, basophils, and eosinophils. It explains the functions of these cells, such as phagocytosis, antigen presentation, and secretion of inflammatory mediators. The document also discusses innate immunity, cell-mediated immunity, and their roles in periodontal disease.
It is in these organs where the cells of the immune system do their actual job of fighting off germs and foreign substances.
Bone marrow. Bone marrow is a sponge-like tissue found inside the bones. ...
Thymus. The thymus is located behind the breastbone above the heart. ...
Lymph nodes. ...
Spleen. ...
Tonsils. ...
Mucous membranes.
It is in these organs where the cells of the immune system do their actual job of fighting off germs and foreign substances.
Bone marrow. Bone marrow is a sponge-like tissue found inside the bones. ...
Thymus. The thymus is located behind the breastbone above the heart. ...
Lymph nodes. ...
Spleen. ...
Tonsils. ...
Mucous membranes.
Antigen processing and presentation by Dr K.Geetha, Associate Professor, Department of Biotechnology, Kamaraj College of Engineering & Technology, Near Virudhunagar, Madurai Dist.
This presentation gives you the detailed description of various cells & organs of immune systems that participates (particularly, in combination), make communication between themselves to regulate the whole immune system very precisely.
Antigen processing and presentation by Dr K.Geetha, Associate Professor, Department of Biotechnology, Kamaraj College of Engineering & Technology, Near Virudhunagar, Madurai Dist.
This presentation gives you the detailed description of various cells & organs of immune systems that participates (particularly, in combination), make communication between themselves to regulate the whole immune system very precisely.
Antigen-antibody interaction, or antigen-antibody reaction, is a specific chemical interaction between antibodies produced by B cells of the white blood cells and antigens during immune reaction. It is the fundamental reaction in the body by which the body is protected from complex foreign molecules, such as pathogens and their chemical toxins. In the blood, the antigens are specifically and with high affinity bound by antibodies to form an antigen-antibody complex. The immune complex is then transported to cellular systems where it can be destroyed or deactivated.
Cytokine Receptors, Mohammad Mufarreh AliMMufarreh
A detailed description of the nature, types, and mechanisms of action of cytokine receptors.
Describes the different functions of cytokines and their role in the regulation of the immune response.
Cytokine receptor signalling and their regulation and the role of cytokines in disease is also covered briefly.
Identify the organs of primary and secondary immune system- lymphoid organs, Know the functions of lymphoid organs, Understand the importance of lymphoid organs and Lymphatic circulatory system
Phagocytosis begins with adhesion of the phagocyte surface receptors to the pathogen, which then is internalized into vesicles called phagosomes.
Inside the phagocyte, the phagosome fuses to lysosomes, whose contents are released with consequent digestion and pathogen elimination.
Changes in the oxidase’s gene system components present in phagolysosome membrane lead to disability in respiratory burst and generation of reactive oxygen species (ROS).
Phagocytosis begins with adhesion of the phagocyte surface receptors to the pathogen, which then is internalized into vesicles called phagosomes.
Inside the phagocyte, the phagosome fuses to lysosomes, whose contents are released with consequent digestion and pathogen elimination.
Changes in the oxidase’s gene system components present in phagolysosome membrane lead to disability in respiratory burst and generation of reactive oxygen species (ROS).
The main effector cells of innate immunity are macrophages, neutrophils, dendritic cells, and natural killer (NK) cells .
Phagocytosis, release of inflammatory mediators, activation of complement system proteins, as well as synthesis of acute phase proteins, cytokines and chemokines are the main mechanisms in innate immunity
Immune system and its functions
The main effector cells of innate immunity are macrophages, neutrophils, dendritic cells, and natural killer (NK) cells .
Types of immune cells
∆Lymphoid cells
-lymphocytes
constitute 20%–40% of the body’s white blood cells and 99% of the cells in the lymph
continually circulate in the blood and lymph and are capable of migrating into the tissue spaces and lymphoid organs
lymphocytes enlarge into 15 µm-diameter blast cells, called lymphoblasts; these cells have a higher cytoplasm : nucleus ratio and more organellar complexity than small lymphocytes.
Lymphoblasts proliferate and eventually differentiate into-
effector cells or into
memory cells.
* B-lymphocytes
*T-lymphocytes
* Natural killer cells
∆mononuclear phagocytes
The mononuclear phagocytic system consists of monocytes circulating in the blood and macrophages in the tissues.
-macrophages
-monocytes
∆granulocytes cells
Granulocytes are at the front lines of attack during an immune response and are considered part of the innate immune system.
Granulocytes are white blood cells (leukocytes) that are classified as neutrophils, basophils, mast cells, or eosinophils on the basis of differences in cellular morphology and the staining of their characteristic cytoplasmic granules
The cytoplasm of all granulocytes is replete with granules that are released in response to contact with pathogens.
These granules contain a variety of proteins with distinct functions:
Some damage pathogens directly;
some regulate trafficking and activity of other white blood cells, including lymphocytes
-neutrophills
-basophils
-eosinophils
-dendritic cells
-mast cells
Ozempic: Preoperative Management of Patients on GLP-1 Receptor Agonists Saeid Safari
Preoperative Management of Patients on GLP-1 Receptor Agonists like Ozempic and Semiglutide
ASA GUIDELINE
NYSORA Guideline
2 Case Reports of Gastric Ultrasound
Pulmonary Thromboembolism - etilogy, types, medical- Surgical and nursing man...VarunMahajani
Disruption of blood supply to lung alveoli due to blockage of one or more pulmonary blood vessels is called as Pulmonary thromboembolism. In this presentation we will discuss its causes, types and its management in depth.
The prostate is an exocrine gland of the male mammalian reproductive system
It is a walnut-sized gland that forms part of the male reproductive system and is located in front of the rectum and just below the urinary bladder
Function is to store and secrete a clear, slightly alkaline fluid that constitutes 10-30% of the volume of the seminal fluid that along with the spermatozoa, constitutes semen
A healthy human prostate measures (4cm-vertical, by 3cm-horizontal, 2cm ant-post ).
It surrounds the urethra just below the urinary bladder. It has anterior, median, posterior and two lateral lobes
It’s work is regulated by androgens which are responsible for male sex characteristics
Generalised disease of the prostate due to hormonal derangement which leads to non malignant enlargement of the gland (increase in the number of epithelial cells and stromal tissue)to cause compression of the urethra leading to symptoms (LUTS
Tom Selleck Health: A Comprehensive Look at the Iconic Actor’s Wellness Journeygreendigital
Tom Selleck, an enduring figure in Hollywood. has captivated audiences for decades with his rugged charm, iconic moustache. and memorable roles in television and film. From his breakout role as Thomas Magnum in Magnum P.I. to his current portrayal of Frank Reagan in Blue Bloods. Selleck's career has spanned over 50 years. But beyond his professional achievements. fans have often been curious about Tom Selleck Health. especially as he has aged in the public eye.
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Introduction
Many have been interested in Tom Selleck health. not only because of his enduring presence on screen but also because of the challenges. and lifestyle choices he has faced and made over the years. This article delves into the various aspects of Tom Selleck health. exploring his fitness regimen, diet, mental health. and the challenges he has encountered as he ages. We'll look at how he maintains his well-being. the health issues he has faced, and his approach to ageing .
Early Life and Career
Childhood and Athletic Beginnings
Tom Selleck was born on January 29, 1945, in Detroit, Michigan, and grew up in Sherman Oaks, California. From an early age, he was involved in sports, particularly basketball. which played a significant role in his physical development. His athletic pursuits continued into college. where he attended the University of Southern California (USC) on a basketball scholarship. This early involvement in sports laid a strong foundation for his physical health and disciplined lifestyle.
Transition to Acting
Selleck's transition from an athlete to an actor came with its physical demands. His first significant role in "Magnum P.I." required him to perform various stunts and maintain a fit appearance. This role, which he played from 1980 to 1988. necessitated a rigorous fitness routine to meet the show's demands. setting the stage for his long-term commitment to health and wellness.
Fitness Regimen
Workout Routine
Tom Selleck health and fitness regimen has evolved. adapting to his changing roles and age. During his "Magnum, P.I." days. Selleck's workouts were intense and focused on building and maintaining muscle mass. His routine included weightlifting, cardiovascular exercises. and specific training for the stunts he performed on the show.
Selleck adjusted his fitness routine as he aged to suit his body's needs. Today, his workouts focus on maintaining flexibility, strength, and cardiovascular health. He incorporates low-impact exercises such as swimming, walking, and light weightlifting. This balanced approach helps him stay fit without putting undue strain on his joints and muscles.
Importance of Flexibility and Mobility
In recent years, Selleck has emphasized the importance of flexibility and mobility in his fitness regimen. Understanding the natural decline in muscle mass and joint flexibility with age. he includes stretching and yoga in his routine. These practices help prevent injuries, improve posture, and maintain mobilit
Title: Sense of Smell
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
Report Back from SGO 2024: What’s the Latest in Cervical Cancer?bkling
Are you curious about what’s new in cervical cancer research or unsure what the findings mean? Join Dr. Emily Ko, a gynecologic oncologist at Penn Medicine, to learn about the latest updates from the Society of Gynecologic Oncology (SGO) 2024 Annual Meeting on Women’s Cancer. Dr. Ko will discuss what the research presented at the conference means for you and answer your questions about the new developments.
Ethanol (CH3CH2OH), or beverage alcohol, is a two-carbon alcohol
that is rapidly distributed in the body and brain. Ethanol alters many
neurochemical systems and has rewarding and addictive properties. It
is the oldest recreational drug and likely contributes to more morbidity,
mortality, and public health costs than all illicit drugs combined. The
5th edition of the Diagnostic and Statistical Manual of Mental Disorders
(DSM-5) integrates alcohol abuse and alcohol dependence into a single
disorder called alcohol use disorder (AUD), with mild, moderate,
and severe subclassifications (American Psychiatric Association, 2013).
In the DSM-5, all types of substance abuse and dependence have been
combined into a single substance use disorder (SUD) on a continuum
from mild to severe. A diagnosis of AUD requires that at least two of
the 11 DSM-5 behaviors be present within a 12-month period (mild
AUD: 2–3 criteria; moderate AUD: 4–5 criteria; severe AUD: 6–11 criteria).
The four main behavioral effects of AUD are impaired control over
drinking, negative social consequences, risky use, and altered physiological
effects (tolerance, withdrawal). This chapter presents an overview
of the prevalence and harmful consequences of AUD in the U.S.,
the systemic nature of the disease, neurocircuitry and stages of AUD,
comorbidities, fetal alcohol spectrum disorders, genetic risk factors, and
pharmacotherapies for AUD.
3. CONTENT
INTRODUCTION
CELLS OF IMMUNE SYSTEM
Lymphocytes ,B cells ,T cells , Natural killer cell
Dendritic Cells, Monocytes, Macrophages, Neutrophils, Eosinophils, Basophils , Mast Cells
TYPES OF IMMUNITY
INNATE & CELL MEDIATED IMMUNITY IN PERIODONTAL DISEASE
CLINICAL IMPLICATION OF IMMUNE RESPONSES
REFERENCES
3
4. INTRODUCTION
The state of periodontal health or disease
depends upon the interaction between the
resident microbiota and the host response.
Periodontal pathogens trigger both inflammatory
reaction and host immune response.
4
5. What Is Immunity
The ability of the body to defend itself against
specific invading agents such as bacteria, toxins,
viruses, and foreign tissue is called immunity.
5
6. The immune system plays a key role in limiting the
infections to the gingival crevice.
The main function of the immune system is to
defend the body against a wide variety of
pathogenic infectious agents with vastly differing
natures, i.e. viruses, bacteria, fungi, protozoa and
parasitic worms.
6
8. The complexity of this task requires a
sophisticated repertoire of mechanisms for the
recognition of, and defense of the body against,
these pathogens.
This is achieved by an array of cells and molecules
which they secrete which are dispersed through-
out the body and collectively constitute the
immune system
8
9. Most of the major cell types of the immune
system are derived from progenitors (stem cells)
in the bone marrow.
Many of the mature cells circulate in the
bloodstream and are dispersed throughout tissues
of the body, while some also congregate in
specialized lymphoid tissues.
9
10. Furthermore, in order to generate effective
immunity, the various cell types cooperate with
each other by means of direct interactions
between cell surface molecules and via the
molecules that they secrete.
10
11. 11
Lymphocytes B cells T cells
Natural killer
cell
Dendritic Cells Monocytes
Macrophages Neutrophils Eosinophils
Basophils Mast Cells
CELLS OF IMMUNITY
15. NEUTROPHIL
Comprise the majority of white blood cells (60–70%).
They are also known as polymorphonuclear leucocytes
because of their multi lobed nuclei and are larger than
most mononuclear blood cells.
Derived from myeloid progenitors in the bone marrow,
granulocytes are released at a rate of seven million per
minute, but are short-lived (2–3 days).
15
16. They contain azurophilic lysosomal granules which,
in addition to myeloperoxidase, lysozyme and acid
hydrolases, contain other antimicrobial proteins
(e.g. defensins and serprocidins).
They also possess secondary specific granules
which contain the iron-binding protein lactoferrin
as well as lytic enzymes
16
17. The main function of neutrophils is the
phagocytosis and intracellular digestion of
particulate antigens (e.g. bacteria) and to produce
reactive oxygen intermediates (ROI) with
antimicrobial potential.
17
19. In addition to producing classical effector
molecules, such as ROI and cytokines , neutrophils
can extrude extracellular fibrillary networks
termed neutrophil extracellular traps (NETs)
These networks are composed mainly of DNA, but
also contain proteins from neutrophil granules
19
20. NETs act as a mesh that traps microorganisms
and, in turn, facilitates their interaction with
neutrophil-derived effector molecules.
NETs have been shown to trap microorganisms —
such as Escherichia coli, Staphylococcus aureus,
Shigella flexneri, Salmonella enterica subspecies
enterica serovar Typhimurium, Candida albicans
and Leishmania amazonensis and promote the
interaction of these pathogens with granule
derived proteins and their subsequent disposal
20
22. DENDRITIC CELL
Dendritic cells are antigen-presenting cells (APCs)
which play a critical role in the regulation of the
adaptive immune response.
DCs were first described by Ralph Steinman
nearly forty years ago.
He found a population of striking dendritic-shaped
cells in the spleen.
22
23. Dendritic cells are so called because, when they
are mature, their cytoplasm extends into
transient spiny dendrites and sheet-like veils.
This provides a large surface area for their main
function of antigen presentation to T
lymphocytes.
23
24. All dendritic cells are derived from bone marrow
stem cells, but appear to be heterogeneous, with
various precursors (including monocytes)
differentiating into dendritic cells when stimulated
by appropriate combinations of cytokines.
Immature dendritic cells are found in tissues
throughout the body and are very efficient at
capturing and processing antigens.
24
25. Mature DCs are defined by key morphological features
and by the presence or absence of various molecules on
the cell surface.
The key morphological characteristic of DCs is the
presence of numerous membrane processes that
extend out from the main cell body (similar to
dendrites on neurons).
25
26. An additional morphological feature of DCs is that they
contain abundant intracellular structures relating to
antigen processing including endosomes, lysosomes, and
Birbeck granules of Langerhans cells of the epidermis.
26
27. Recently, subsets of DC were recognized based on their
function in immune responses. DC1 cells, also called
myeloid DCs, express different Toll-like receptors
(TLR)-2, -3, -4, and -7.
After encountering different natural ligands or
pathogens for these TLRs in the blood, DC1 cells
become activated and mature into antigen-presenting
cells (APC) that can secrete Th-1 or Th-2 cytokines and
prime naive T cells for a proper immune response.
27
29. What is the function of dendritic
cells?
The function of DCs falls broadly into three categories, each
of which involve antigen presentation.
29
30. 30
• The first category of DCs function is antigen presentation
and activation of T cells.
• The second category of DC function is not as well
established, but it has been suggested that a different
class of DCs exist with the function of inducing and
maintaining immune tolerance.
• The third category of DCs, known as follicular DCs, appear
to work to maintain immune memory in tandem with B cells.
31. EOSINOPHIL
The granulocytes whose granules stain with acidic
dyes are called eosinophils.
They comprise 2–5% of white
blood cells and have bilobed nuclei.
31
32. In contrast to the phagocytosis and intracellular
digestion normally displayed by neutrophils, eosinophils
secrete their granule contents for extracellular
digestion of infectious pathogens which are too large
to be engulfed.
Eosinophils also produce cytokines, prostaglandins and
leucotrienes, and enzymes which can inhibit the
inflammatory products of mast cells
32
33. Eosinophils have Fc receptors for IgG and IgE
antibodies and for C3b, enabling them to bind to
opsonized targets.
They then secrete their antibiotic granule
contents (including major basic protein and
eosinophil cationic protein) and reactive oxygen
species to bring about damage to the target.
33
34. Monocytes and Macrophages
Monocytes, which constitute 5–10% of mononuclear
leucocytes in the blood, differentiate into
macrophages when they migrate into tissues.
Monocytes are larger than most lymphocytes and
have a kidney-shaped nucleus: they possess
azurophilic lysosomal granules containing lysozyme,
acidhydrolases and myeloperoxidase.
34
35. The blood monocytes arise from myeloid progenitors in
the bone marrow.
Macrophages can be resident in tissues for prolonged
periods of time where they take on various morphologies,
and are known by different names, depending on their
tissues of residence, e.g. Kupffer cells in the liver,
mesangial cells in the kidney and microglial cells in the
brain.
35
36. Macrophages also participate in the effector phase of humoral immunity. Macrophages
efficiently phagocytose and destroy microbes that are opsonized (coated) by IgG or C3b.
They are key effector cells in certain forms of cell-mediated immunity, the reaction that serves
to eliminate intracellular microbes. In this type of response, T cells activate macrophages and
enhance their ability to kill ingested microbes .
Macrophages that have phagocytosed microbes and protein antigens process the antigens and
present peptide fragments to T cells. Thus, macrophages function as APCs in T-cell activation.
The important functions of macrophage are in the induction and effector phases of adaptive
immune responses.
36
38. Phagocytic activity increases when there is tissue
damage and inflammation, which releases
substances that attract macrophages.
Activated macrophages migrate more vigorously in
response to chemotactic factors and should enter
sites of inflammation.
38
39. The activity of mononuclear phagocytes against cancer
cells in humans is less well understood than the
phagocytosis of microorganisms.
Phagocytes are thought to suppress the growth of
spontaneously arising tumors.
39
40. The ability of these cells to control malignant cells
may not involve phagocytosis but may be related to
secreted cellular products such as lysosomal
enzymes, oxygen metabolites, proteinases, and TNFα
The proteolytic enzymes present on the surface
membrane of monocytes also may play a role in tumor
rejection
40
41. Basophils
Basophilic granulocytes (basophils) derive their name
from the affinity of their cytoplasmic granules for
certain basic dyes.
They constitute less than 1% of white blood cells.
Basophils are of hematopoietic origin.
Typically mature in the bone marrow and then circulate
in the peripheral blood, from where they can then be
recruited into the tissues
41
42. Basophils have a short life-span of several days.
Interleukin-3 (IL-3) promotes the production and survival of human basophils in vitro and
can induce basophili in vivo.
Mediators stored preformed in the cytoplasmic granules of basophils include chondroitin
sulphates, proteases and histamine
Chondroitin sulphates probably contribute to the storage of histamine and neutral
proteases, and basophils are the source of most of the histamine found in normal human
blood.
42
43. A mast cell (also known as a mastocyte or a labrocyte) is a
resident granulocyte of several types of tissues that contains
many granules rich in histamine and heparin.
The mast cell is very similar in both appearance and function to
the basophil. However, they are not the same, as they arise
from different cell lines.
Mast cells were first described by Paul Ehrlich in 1878.
43Mast cell
44. Two types of mast cells are recognized,
A. connective tissue mast cell
B. mucosal mast cells.
Mast cells are present in most tissues
characteristically surrounding blood vessels and nerves,
and are especially prominent near the boundaries
between the outside world and the internal milieu, such
as the skin, mucosa of the lungs, and digestive tract, as
well as the mouth, conjunctiva, and nose.
44
45. Mast cells and basophils may have particularly
important roles as effector cells in initiating and
or amplifying IgE-dependent inflammatory
reactions
Both cells play an important protective role as
well, being intimately involved in wound healing and
defense against pathogens
45
Role Of Basophil And Mast Cell
47. Basophils appear in many specific kinds of
inflammatory reactions, particularly those that cause
allergic symptoms.
They contain anticoagulant heparin, which prevents
blood from clotting too quickly.
They also contain the vasodilator histamine, which
promotes blood flow to tissues.
They can be found in unusually high numbers at sites
of ectoparasite infection.
47
48. Basophils have protein receptors on their cell
surface that bind IgE, an immunoglobulin involved in
macroparasite defense and allergy.
It is the bound IgE antibody that confers a
selective response of these cells to environmental
substances, for example, pollen proteins or helminth
antigens.
Recent studies in mice suggest that basophils may
also regulate the behavior of T cells and mediate
the magnitude of the secondary immune response
48
49. Mast cells are important in immediate
inflammation.
It is best known for their role in allergy and
anaphylaxis.
They possess receptors for complement
components (C3a and C5a) as well as receptors for
the Fc portion of the antibody molecules IgE and
IgG .
49
50. The stimulation of these receptors can result in
activation and secretion of vasoactive substances
that increase vascular permeability and dilation,
two important signs of anaphylaxis
Mast cells can synthesize, de novo, other
inflammatory mediators, such as the slow-reacting
substances of anaphylaxis (SRS- A), tumor
necrosis factor-a (TNF-a), and leukotriene C4.
50
52. CARRANZAS Clinical Periodontology-10th Edition.
Periodontics-grant,stern,listgarten-8th Edition.
Robbins And Cotran Pathologic Basis Of Disease - 7th and 8th Edition
Guyton - Textbook Of Medical Physiology 11th Ed - 2005
Cells Of The Immune System ENCYCLOPEDIA OF LIFE SCIENCES / & 2001 Nature Publishing Group ;Ian Todd ,
University Of Nottingham, Nottingham, UK
Neutrophils In The Activation And Regulation Of Innate And Adaptive Immunity Alberto Mantovani, Marco
A. Cassatella, Claudio Costantini And Sébastien Jaillon NATURE REVIEWS IMMUNOLOGY VOLUME 11 AUGUST
2011
Mast Cells And Basophils In Acquired Immunity Jochen Wedemeyer And Stephen J Galli ; British Medical Bulletin
2000; 56 (No. 4): 936-955
Cells And Cellular Activities Of The Immune System: Granulocytes And Mononuclear Cells
52REFERENCES
54. What Is Azurophilic Granules ?
An azurophil is an object readily stained with an azure stain.
Neutrophils in particular are known for containing azurophils loaded
with a wide variety of anti-microbial defensins that fuse with
phagocytic vacuoles.
Azurophils may contain myeloperoxidase, phospholipase A2, Acid
Hydrolases, Elastase, defensins, neutral serine proteases,
bactericidal/permeability-increasing protein, lysozyme, cathepsin
G, proteinase 3, and proteoglycans.
Azurophil granules are also known as "primary granules.
54
55. CONTENTS
Cells of immune system
Lymphocytes ,B cells ,T cells , natural killer cell
Types of immunity
Innate & cell mediated immunity in periodontal disease
Clinical implication of immune responses
Conclusion
References
55
56. LYMPHOCYTE
Lymphocytes are 20-40% of WBC, 99% of cells in
lymph.
Only cells of immune system exhibit specific receptor
for antigen .
Bridge between various parts of immune system
Small, round 5-12 m diameter spherical densely
compact nucleus occupies almost entire cell & scanty
cytoplasm.
56
57. Lymphocytes includes three types of cells.
T-lymphocytes or T cells, which are derived from
the thymus and play a role in cell-mediated
immunity.
B-lymphocytes or B-cells which are derived from
liver, spleen and bone marrow are the precursors
of plasma cells and play a role in humoral immunity.
Natural killer (NK) and killer (K) cells.
57
62. T Cell
About 70% of human blood lymphocytes are T cells.
Those cells destined to be T cell which leave the bone
marrow via the blood stream and move to the thymus.
There the T cell become able to differentiate between self
and nonself antigens.
62
63. The main functions of T lymphocytes are to exert
effects on other cells, either regulating the
activity of cells of the immune system or killing
cells that are infected or malignant.
T cells have surface antigen receptors, but there
is no secreted form of these equivalent to
antibodies.
63
64. Furthermore, T cells cannot recognize antigens in
their native forms, but only when they are
presented on the surface of antigen-presenting
cells (APCs).
The antigen receptors of most T cells (ab T cells)
are composed of two polypeptides called a and b
chains, and they interact with peptides derived
from the degradation (processing) of foreign
antigenic proteins
64
65. The T lymphocytes are associated with two types of
immunological functions,
65
EFFECTOR REGULATORY
66. The effector functions include activities such as
killing of virally infected cells and tumors.
The regulatory function are represented by their
ability to amplify or suppress through cytokines or
other effector lymphocytes including B and T
cells.
66
67. T cells receptor has two parts TCR and CD3.
CD3 is present on all T cells .
Presently two types of TCR are defined:TCR-1 &
TCR-2
Both receptors are associated with a complex of
a polypeptides making up the CD3 complex.
67
68. Thus a T cell is defined either by TCR-1 or TCR2
which is associated with CD3.
Approximately 95% of blood T cells express TCR-
2.
TCR-2 bearing cells can be further divided into
CD4+ T cells and CD8+ cells .
68
69. HELPER T CELLS
Helper T cells are the major driving force and the
main regulators of the immune defense.
Their primary task is to activate B cells and killer T
cells.
However, the helper T cells themselves must be
activated.
69
70. This happens when a macrophage or dendritic cell,
which has eaten an invader, travels to the nearest
lymph node to present information about the
captured pathogen.
The phagocyte displays an antigen fragment from
the invader on its own surface, a process called
antigen presentation.
70
71. When the receptor of a helper T cell recognizes
the antigen, the T cell is activated.
Once activated, helper T cells start to divide and
to produce proteins that activate B and T cells as
well as other immune cells.
71
72. T-INDUCER CELLS :
Some T cells induce other T cells to become
suppressor T cells and involve in regulation of the
immune response.
These cells have common phenotypic
characteristics.
Examples are Ly1a and Ly2 cells in mice.
72
73. T-suppressor cells
Suppressor effector T cells bind antigen and
release factor that inactivate T-helper cells.
T-suppressor cells can:
Suppress delayed –type hypersensitivity
reactions,
Prevent proliferation and antibody secretion by
antigen-binding B cells,
Suppress antibody secretion by some types of B
cells.
73
74. T-CYTOTOXIC CELLS :
These cells recognize certain histocompatibility
antigens and are capable of killing foreign cells
(i.e., virus) and altered self-cells (i.e. tumor
antigens).
T-cytotoxic cells are important in the
cytotoxicity of graft reactions and graft-versus-
host reactions.
74
75. Cytolysis requires direct contact between the T-
cytotoxic cell and the target cell, occurs as a
result of antigen specific receptors on the T-cells.
75
76. T-CONTRASUPPRESSOR CELLS
These cells present the inactivation of T-helper
and T-inducer cells by the action of suppressor
effector T-cells.
They are antigen specific and may be important in
immunologic memory.
76
77. B cells
B lymphocytes represents 3 to 15% of circulating
lymphoid cells and are primarily defined by
surface immunoglobulins (Ig).
The B lymphocytes are common in areas of
antibody production, such as the germinal centers
of the lymph nodes and diffuse lymphoid tissue of
mucosal systems.
77
78. The main function of a B cell is to secrete soluble
recognition molecules called antibodies which
specifically bind to an antigen recognized by that
B cell.
Throughout the life, bone marrow remains the
major repository of stem cells for B lymphocytes.
78
79. A B cell will only produce antibodies when it has
been activated by binding antigen; this activation
process also usually requires help from T cells. The
activated B cell undergoes multiple divisions and
some of the resulting cells differentiate into
antibody-secreting cells.
These are known as plasma cells, and they possess
copious rough endoplasmic reticulum involved in
antibody synthesis.
79
80. An important aspect of antigen recognition by B
cells is that these lymphocytes, and the
antibodies they produce, bind to antigens in their
natural or native form, i.e. as they occur as
constituents of pathogens
80
82. Natural Killer Cells
Natural killer (NK) cells constitute up to 15% of human
blood lymphocytes.
Together with δ T cells and about 50% of CD8+ T cells
they are known as large granular lymphocytes because,
compared with most T and B lymphocytes, they have
more cytoplasm and contain prominent granules.
82
83. In contrast to all T and B cells, NK cells do not
express antigen-specific receptors and do not
possess the adaptive property of memory cell
development; they are therefore considered to
form part of the innate immune system.
Their main function is to kill infected cells and
tumor cells by inducing apoptosis of their targets.
83
85. Since they lack antigen receptors, NK cells do not
recognize specific antigens on the surface of a
target cell.
Instead, they detect molecular changes in the
surface of a cell which are indicative of that cell
being abnormal and therefore a potential threat to
the body.
They kill cells with reduced expression of MHC
class I molecules, as can result from viral infection
or malignant transformation.
85
86. NK cells express surface ligands for MHC class I
known as killer inhibitory receptors (KIRs)
because their binding to MHC class I on the
surface of a potential target cell inhibits the
cytotoxic activity of the NK cell.
This prevents NK cells from killing normal tissue
cells with normal levels of MHC class I expression
86
91. Acquired Or Adaptive Immunity
Specific
Resistance that an individual acquires during his
life time
May be weak / absent on first exposure
Increases with subsequent exposures to same
specific pathogen
91
93. Active immunity is the resistance developed by an
individual as a result of an antigenic stimulus.
Involves the synthesis of antibodies and/or the
production of immunologically active cells.
93
94. Passive immunity is the resistance that is
transmitted to a recipient in a readymade form as
passive immunity.
Preformed antibodies are administered
94
95. 95
There are two types of effecter mechanisms that
mediate specific immune response:
• Immune responses are those mediated by a cell
product of the lymphoid tissues referred to as
antibody.
• Associated with the fluid phase of blood (plasma
or serum.
Humoral Immunity
• Immune reactions reside in cells of the lymphoid
system,
• Are mediated by specifically sensitized
lymphocytes themselves
Cell Mediated
Immunity
97. NATURAL OR INNATE
(NON SPECIFIC)
First line of defense against invasion by microbes.
Inborn resistance .
First time a pathogen is encountered.
Does not require prior exposure .
Not modified significantly by repeated exposures.
Eg: phagocytosis by leukocytes, natural killer cells,
tissue secretion and complement.
97
98. Mechanism involved in innate immunity are :
Epithelial surfaces :
Intact skin and mucous membrane
Protection against invasion by microorganism.
Eg: mucosa of respiratory tract, mucopolysaccharides capable
of neutralizing the bacterial products.
The mouth is constantly bathed in saliva, contain antibodies, iga,
t-helper and suppressor cell, macrophages.
98
99. Antibacterial substance in blood and tissues :
The complement system possess bactericidal activity .
Destroys pathogenic bacteria invading the blood and tissues.
Substances possessing antibacterial property include:
a) Beta lysine – active against anthrax, and related bacteria
b) Basic polypeptides such leukins.
c) Acidic substances such as lactic acid found in muscle tissue,
has anti bacterial action.
99
100. Cellular factor in innate immunity :
Inflammation :
Tissue injury and irritation by the entry of
pathogens or other irritation
Causes inflammation, which is an important non-
specific mechanism of defence.
Help in the initial defense.
100
102. Fever :
Rise in temperature following infection is a natural
defense mechanism.
Help not merely to accelerate physiological
processes but many in some cases.
Actually destroy the infecting pathogens.
102
103. Acute phase proteins :
Infection or injury leads to a sudden increase in plasma
concentration of certain proteins, collectively called acute
phase proteins.
Include c-reactive protein, mannose binding protein, alpha 1-
acid glycoprotein, serum amyloid p component and many
others.
Believed to enhance host resistance,
Prevent tissue injury .
Promote repair of inflammatory lesions.
103
104. Innate Mechanisms Of Defence Against Periodontal Disease
Salivary secretions are protective
Exerts a major influences on plaque
Mechanically cleanse the exposed oral surfaces
By buffering acids produced by bacteria
By controlling bacterial activity
104
105. Morphology And Physiology Of The Dento-gingival Region Contributing To
Gingival Defense :
High turnover rate of the junctional epithelium.
The constant renewal of these epithelial cells.
The ability of junction epithelium to produce
attachment to the tooth - counteract subgingival
plaque growth.
105
106. Intercellular material, by the epithelial cells may
prevent the penetration of bacteria into the
epithelium.
The loose arrangement of the junctional epithelial
cells, facilitates the transport of phagocytic cells
and antimicrobial substances from the vascular
system into this region.
106
107. In 1971 Lange and Schroeder demonstrated that
the epithelial cells in the base region of the sulcus
contain lysosomes and cells also showed
phagocytic activity toward bacteria.
Epidermal cell, mainly keratinocytes, to a lesser
extent melanocytes and Langerhan cells, release a
variety of regulatory proteins (cytokines) which
may assist local defense by recruitment and
enhancement of phagocyte functions. (E.g- IL-3,
TGF-alfa and beta, TNF-alpha etc.,)
107
108. Functions Of Innate Immune Mechanisms In Periodontal Diseases
Various factors and cells make up the innate
immune system.
Include complement, acute-phase proteins, and
interferons.
The complement system appears to be down-
regulated in patients with periodontal diseases.
108
109. The decrease in complement function results from
both bacterial and host actions and may increase the
susceptibility of the host to periodontal disease.
Neutrophils have a primary role in the
immunopathogenesis of at least some forms of
periodontal disease.
The basic paradigm shift is that in some cases, PMNs
do not exhibit a decrease in function, but rather they
become hyperactive and are primed for actions that
result in tissue breakdown. ease.
109
110. Functions Of Adaptive Immunity In
Periodontal Diseases
T lymphocytes, B lymphocytes/plasma cells, and
macrophages.
The mechanisms of innate and adaptive immunity are
extensive, overlapping, and redundant.
If the functions of innate immunity, do not abate the
initial infection, an inflammatory infiltrate becomes
localized to the connective tissue of the affected area.
110
111. This infiltrate is composed mainly of lymphocytes and
macrophages, with some neutrophils, and reflects an
adaptive immune response.
Lymphocytes, macrophages, and other immune cells
produce cytokines that drive the immune response to
clear the infection.
The early inflammatory infiltrate is dominated by
lymphocytes; Predominantly, T cells.
T cells have two basic subpopulations: CD4 or helper T
cells, and CD8, which are suppressor/cytotoxic T cells.
111
112. B cells predominates at the expense of T cells when
gingivitis progresses to a periodontitis.
There is a decreased CD4/CD8 ratio
And an increase in memory T cells.
B cells mature and differentiate into plasma cells,
which ultimately produce antibodies
112
113. Antibody titers and disease severity commonly
express a positive relationship – that is, patients
with higher titers have severe disease, especially
in patients with chronic periodontitis or localized
aggressive periodontitis.
Antibody titers decrease after resolution of
periodontal disease
113
114. Immune Responses As Markers Of Susceptibility Of Periodontal
Diseases
IgG3 and IgG1 to A. actinomycetemcomitans were
significantly elevated in localized juvenile
periodontitis and rapidly progressive periodontitis
patients, while IgG2 was similar among the disease
groups.
Only the rapidly progressive periodontitis
patients had IgG4 to A. actinomycetemcomitans.
114
115. Rapidly progressive periodontitis and adult
periodontitis patient had elevated IgG2, IgG1 and
IgG4 to P. gingivalis.
Patients with rapidly progressive periodontitis had
elevated IgG1 to P. intermedia.
IgG2 was the primary response to C. rectus in the
localized juvenile periodontitis and adult
periodontitis.
115
116. Serum IgG2 levels were elevated in localized
juvenile periodontitis patients compared with
healthy controls.
The IgG2 antibody levels to A. actinomycetem
comitans were similar among adult periodontitis
and generalized juvenile periodontitis patients and
healthy controls.
116
117. CONCLUSION
Pathogenesis of periodontal destruction involves a complex
interplay between bacterial pathogens and the host tissues.
In order to generate effective immunity, the various cell types
cooperate with each other by means of direct interactions
between cell surface molecules and via the molecules that they
secrete.
Recent investigation have revealed that not all strains of a
specific microbial species are equal in their capacity to cause
disease, and not all host are equal in their susceptibility to
diseases.
The challenge for future is to be able to better identify the
more virulent bacterial strain and the more susceptible host.
117
119. CARRANZAS Clinical Periodontology-10th Edition.
Periodontics-grant,stern,listgarten-8th Edition.
Robbins And Cotran Pathologic Basis Of Disease - 7th and 8th Edition
Guyton - Textbook Of Medical Physiology 11th Ed - 2005
Cells Of The Immune System ENCYCLOPEDIA OF LIFE SCIENCES / & 2001 ;Ian Todd ,
University Of Nottingham, Nottingham, UK
Neutrophils In The Activation And Regulation Of Innate And Adaptive Immunity Alberto
Mantovani, Marco A. Cassatella, NATURE REVIEWS IMMUNOLOGY VOLUME 11 AUGUST 2011
Mast Cells And Basophils In Acquired Immunity Jochen Wedemeyer And Stephen J Galli ; British
Medical Bulletin 2000; 56 (No. 4): 936-955
Cells And Cellular Activities Of The Immune System: Granulocytes And Mononuclear Cells
Molecular Biology of the Cell. 4th edition.
119
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