The document outlines the immune regulation system, highlighting its role in protecting the body against infections through innate and adaptive immunity. It details the phases of the immune response, including recognition, activation, and elimination of pathogens, as well as the concept of immunological tolerance to prevent autoimmune diseases. Key components like antigen-presenting cells and regulatory cells are discussed, emphasizing their importance in maintaining immune balance.

1. IMMUNE REGULATION SYSTEM
PRESENTED BY
DR.ABDIRISACK MOKHTAR MOHAMED.

2. INTRODUCTION
• what is immune?
=Immune refers to the body's ability to resist or defend against infections and
diseases.
✓Imuumunity mean protection from disease and more specifically, infectious disease.
• The cells and molecules responsible for Immunity constitute the immune system
• There are two types of Immunity:
• Innate Immunity
• Adaptive Immunity

3. INNATE AND ADAPTIVE IMMUNE
RESPONSES

4. IMMUNE REGULATION SYSTEM
• The immune regulation system involves a complex network of cells, tissues, and
molecules that work together to maintain homeostasis and respond to
pathogens.

5. THE I M M U N E RESPONSE
• The immune response is the body's defense mechanism against pathogens
such as viruses, bacteria, and other foreign substances. It involves two main
components: the innate immune response and the adaptive immune response.
• Innate Immune Response
• 1. Immediate Response: Activated within minutes to hours of infection.
• 2. Physical Barriers: Skin, mucous membranes, and secretions act as the first
line of defense.
• 3. Immune Cells:
• Phagocytes: Macrophages and neutrophils engulf and destroy pathogens.
• Natural Killer Cells: Target and kill infected or cancerous cells.
• 4. Inflammation: A local response characterized by redness, heat, swelling, and
pain, which helps contain infections and recruits immune cells.
• 5. Complement System: A series of proteins that enhance the ability to clear
pathogens and promote inflammation.

6. • Adaptive Immune Response
• 1. Specificity: Targets specific pathogens and develops memory for future
encounters.
• 2. Lymphocytes:
• B Cells: Produce antibodies that neutralize pathogens and mark them for
destruction.
• T Cells:
• Helper T Cells (CD4+ T Cells): Activate other immune cells and enhance the immune
response.
• Cytotoxic T Cells (CD8+ T Cells): Kill infected or abnormal cells.
• 3. Antigen Presentation: Dendritic cells and macrophages present antigens to T cells,
initiating the adaptive response.
• 4. Memory Cells: After an infection, some B and T cells become memory cells,

7. • Phases of Immune Response
• 1. Recognition: Detection of pathogens by immune cells.
• 2. Activation: Lymphocytes are activated and proliferate.
• 3. Effector Phase: Active immune cells eliminate pathogens.

8. IMMUNOLOGICAL TOLERANCE
• Immunological tolerance refers to the state in which the immune
system does not mount an attack against self-antigens, thus
preventing autoimmune diseases

9. TYPES OF IMMUNOLOGICALY TOLERANCE
1. CENTRAL TOLERANCE:
• Occurs during the development of
immune cells in the thymus (for T
cells) and bone marrow (for B cells).
• Immature lymphocytes that strongly
recognize self-antigens are deleted
or altered to ensure that self-
reactive cells do not enter
circulation.
2: PERIPHERAL TOLERANCE
• Takes place in the periphery after lymphocytes
have matured and left primary lymphoid organs.
• Mechanisms include:
• Anergy: Self-reactive T cells become functionally
inactive.
• Suppression: Regulatory T cells (Tregs) inhibit the
activation and function of other immune cells.
• Deletion: Self-reactive cells can be induced to
undergo apoptosis.

10. ANTIGEN-PRESENTING CELLS (APCS)
• Antigen-Presenting Cells (APCs): Dendritic cells and macrophages
that process and present antigens to T cells, activating the
adaptive immune response.

11. REGULATORY CELLS
• Regulatory T cells (Tregs) play a crucial role in suppressing immune responses
to prevent autoimmunity and maintain tolerance to self-antigens.

12. CYTOKINES AND CHEMOKINES
• Signaling molecules that mediate and regulate immunity and inflammation.
They help in cell communication and orchestrating the immune response

13. CONCLUSION
• the immune regulation system is essential for distinguishing between self and
non-self, mounting appropriate responses, and maintaining balance to prevent
overactive or inadequate immune responses.