MCMP 422

1. MCMP 422 • Tony Hazbun • RHPH 406D • Hazbun@pharmacy.purdue.edu • Include MCMP 422 in the subject line

2. MCMP422Immunology Immunology is important personally and professionally! Learn the language - use the glossary and index RNR - Reading, Note taking, Reviewing All materials in Chapters 1-5 are examinable (with exceptions) plus extra material from class

3. What and why? • Immunology: Science of how the body responds to foreign agents • Immune system: the organs, cells and molecules that defend and respond to pathogens/allergens • Organ transplantation, cancer, immunodeficiency diseases, infectious diseases

4. Immunology • How do we recognize foreign structures? • How do we recognize self vs non-self? • How do we stop and remove invading agents? Pharmacy and Therapy Perspective • How can we use the immune system as a therapeutic agent? • How do drugs affect the immune system?

5. Chapter 1 Concepts What components make up the immune system? Cells, organs, cytokines and other molecules involved in the immune system What is the goal of the immune system? To clear pathogens in our body How do we classify immune responses? Innate and adaptive immune responses What are the side effects of the immune system? Autoimmune diseases, Allergies, Transplantation Rejection

6. Machinery of the Immune system 1. Tissues/organs bone marrow, thymus, spleen, lymph nodes 2. Cells lymphocytes, dendritic cells, macrophages, natural killer cells, granulocytes (neutrophils, basophils, eosinophils), mast cells Blood-borne proteins complement and mannose-binding proteins

7. Origin of Immunology - individuals who survived a disease seemed to be untouched upon re-exposure Vaccination/Immunization - procedure where disease is prevented by deliberate exposure to infectious agent that cannot cause disease. Vaccinia - mild disease caused by cowpox Edward Jenner - first demonstration of vaccination

8. Figure 1-2 Pathogen - any organism that can cause disease

9. Diversity of Pathogens • Four Classes • Bacteria • Fungi • Viruses • Parasites • Opportunistic pathogens e.g. Pneumocystis carinii • Pathogen-Host relationship

10. How Clean are You? Part of bodyBacteria Head (scalp) 1,000,000 /cm2 Surface of skin 1000 /cm2 Saliva 100,000,000 /g Nose mucus 10,000,000 /g Faeces over 100,000,000 /g

11. Defenses against Pathogens Physical Defenses 1. Skin - Tough water-proof Barrier - Pathogen Penetration is difficult - Breached by wounds/mosquito 2. Mucosal surfaces - line body cavities - epithelial cells covered with mucus - mucus thick fluid layer containing glycoproteins, proteoglycans and enzymes - e.g. mucus in lungs traps pathogens Immune Defenses 1. Innate - physical defenses are part of innate immunity 2. Adaptive

12. Physical Barriers • Lungs: Mucus, cilia trap and move pathogens • Nose: Mucus traps pathogens which are then swallowed or blown out • Mouth: Friendly bacteria, Saliva • Eyes: lysozyme • Stomach: acid neutralization • Intestine: Friendly bacteria • Urogenital tract: Slightly acid conditions

13. Recognition (Binding event) Immune disorders Signal (Self) Effector mechanisms Immunity: Three Basic Parts Pathogen (Foreign) Effector Cells Complement Two types of Immunity - Innate or Adaptive

14. Innate Immunity • Ancient system - present in invertebrates • naïve, immediate, everyday immunity • Molecules recognize common features of pathogens • Lectin • Phagocytes, large lymphocytes (NK cells) • Complement

15. Adaptive Immunity • Newer system - present in fish, birds, human • specialized, late, immunity • Molecules recognize specific features of pathogens • Antibodies • B and T cells - small lymphocytes • Immunological memory

16. Figure 1-5 part 1 of 2 Example of Innate Immunity Complement - blood borne (serum) proteins that tag pathogens or attack them directly Effector cell - engulf bacteria, kill virus infected cells, attack pathogens Endocytosis - process by which extracellular material is taken up

17. One type of effector cell is the phagocyte

18. Figure 1-6 Innate Immunity Cytokines = signaling molecules --> inflammation/adaptive immunity Phagocytosis = “phagos” means to eat Inflammation is sometimes an unwanted by-product! Inflammatory cells = WBC’s contributing to inflammation

19. Inflammation • Inflammation - local accumulation of fluid and cells involved in the immune response • What happens when inflammation is induced • Blood capillary dilation => heat (calor) & redness (rubor) - Local dilation of blood capillaries = increase of blood to the area (DOES NOT increase blood flow) • Vascular dilation (vasodilation) => swelling (tumor) & pain (dolor) • Extravasation - movement of cells/fluid into connective tissue. A) change in adhesiveness of the endothelial tissue allowing immune cells to attach and migrate into the connective tissue B) vascular dilation - gaps in endothelial cells

20. Example of inflammation gone bad: Sepsis Systemic inflammatory response syndrome (SIRS) Results from the body's systemic over-response to infection Treatment: broad-spectrum antibiotics and supportive therapy Disturbance of innate immunity during sepsis and multiorgan dysfunction syndrome (MODS) probably linked to uncontrolled activation of the complement system Future Drug therapies could be used that modulate pro-inflammatory and anti-inflammatory factors

21. Innate and Adaptive responses Innate • Pathogen independent • Immediate (hours) • Neutrophils • Macrophages • Mast cells • Eosinophils • Basophils • NK cells • “Large Lymphocytes” = NK cells Adaptive • Pathogen-dependent • Slower (days) • Dendritic cells • B cells • T cells (CD4 or CD8) • “Small Lymphocytes” = B & T cells Both systems “talk” to each other to modulate response Both systems use leukocytes = white blood cells

22. What if Innate Immunity is not Enough? • Innate immunity keeps us healthy most of the time • Some pathogens escape the innate immune process • Need a specific system to adapt to a specific pathogen - Hence vertebrates evolved the Adaptive immune response

23. Principles of Adaptive Immunity • Lymphocytes each with different specificity generated by gene rearrangements • Small fraction of total pool of lymphocytes can recognize the pathogen • Pathogen recognizing lymphocyte is amplified - Clonal amplification • Pathogen recognizing lymphocyte can persist providing long-term immunological memory • Primary vs Secondary immune response eg. Influenza/Measles/Vaccination

24. Figure 1-7 Characteristics of Innate vs Adaptive Immunity ADAPTIVE INNATE = genes are constant = genes are rearranged Leukocytes - white blood cells that increase the immune response to ongoing infection

26. Innate vs Adaptive Molecular Recognition • Most important difference: Receptors used to recognize pathogens • Innate immunity: Receptors recognize conserved structures present in many pathogens (usually a repetitive pattern) • Pathogen-associated Molecular Patterns (PAMPs): LPS, peptidoglycan, lipids, mannose, bacterial DNA and viral RNA • e.g. Mannose-binding Lectin (MBL) • Adaptive immunity: Receptors recognize a specific structure unique to that pathogen e.g. Antibodies

27. Figure 1-11 part 1 of 2 Flowchart of Hematopoiesis Pluripotent stem cell Self-renewal

28. Figure 1-11 Flowchart of Hematopoiesis Leukocytes

29. Myeloid Lineage

30. Granulocytes (Myeloid progenitor) Polymorphonuclear leukocytes (PMLs) Figure 1-9 part 3 of 6 Neutrophils: Most abundant Phagocyte Effector cells of Innate Immunity Short-lived - Pus Eosinophils: Worms/intestinal parasites Amplify inflammation Bind IgE Very Toxic - Pathogen and host Chronic asthma Basophils: Rare Unknown function Bind to IgE

31. Figure 1-9 part 5 of 6 • Circulate in blood • Bigger than PMLs • Look similar • Immature form of macrophage • Scavengers • Phagocytose pathogens, cells, debris • Secrete cytokines

32. Figure 1-13

33. Macrophages respond by two mechanisms - use 2 different receptors. Phagocytosis - Phagosome fuses with lysosome - toxic small molecules and hydrolytic enzymes kill/degrade the bacteria Signaling - bacterial component binds receptor - initiates transcription - inflammatory cytokines synthesized and secreted

34. Star-shape • In tissue • Cellular messenger • Cargo cell • Connective tissue • Unknown progenitor • Granules • Degranulation major contributor to inflammation and allergies

35. Large lymphocytes NK cells Innate immunity Small lymphocytes B cells T cells Adaptive immunity Lymphoid Lineage Cells

36. Figure 1-9 part 2 of 6 Lymp • Large lymphocyte with granular cytoplasm • Effector cell of innate immunity 1) kill viral infected cells 2) secrete cytokines that interfere with virus infections

37. Adaptive IR • Small and immature • Activated by pathogen • Two types • - B cell • - T cell • B cells have B cell receptors and secrete Ab • T cells have T cell receptors

38. Erythroid Lineage

39. Figure 1-9 part 6 of 6 • Giant nucleus • Resident of bone marrow • Fusion of precursor cells • Fragments to make platelets • Gas transport • Infected by Plasmodium falciparum

40. Lymphoid Myeloid Erythroid Neulasta (Amgen): Granulocyte Colony-Stimulating Factor (G-CSF) Recovery from Neutropenia & protect against Bacterial disease Leukine (Schering-Plough): Granulocyte-Macrophage Colony-Stimulating Factor (GM-CSF), Recovery from Neutropenia and protection against Bacterial/fungal/parasitic disease

41. Plasma White blood cells Red blood cells Centrifuged blood sample

42. Figure 1-12

43. High WBC could be a sign of infection or leukemia Low WBC bone marrow diseases or HIV Polys = polymorphonucleocytes - mainly neutrophils High lymphocyte count indicates the bacterial or viral infection

44. Figure 1-15 The lymph system and sites of lymphoid tissue Primary (Red) and Secondary (yellow) GALT, BALT, MALT Thoracic Duct Lymphpatic vessels - fluid collection Lymph nodes - junctions of vessels

45. Recirculation Draining Lymph node Edema - is worse when patient is inactive Afferent (entry) Efferent (exit)

46. Figure 1-17 part 1 of 2 Communications Center Afferent vessels bring in the lymph from infected tissue Efferent vessels place of exit for non-activated lymphocytes

47. B-cell area (follicle)

48. Lymphocytes Efferent lymph artery Lymphocyte not activated T-cell area Afferent lymph Pathogen Dendritic cells Activated by dendritic cell T helper cell (lymph node) T helper cell (Infection site) Cytotoxic T cell (Infection site) Activate B cells Activate Macrophages Kills infected host cells Make Antibodies

49. Lymphocytes enter node through artery Tcells migrate to the T-cell area and if they meet a dendritic cell that is carrying pathogens from an infection site they get activated - to divide into functional effector cells. Some T-cells stay in the lymph node and become T-helper cells - secrete cytokines (soluble proteins) and have receptors that contact B-cells. This helps the B-cells differentiate into plasma cells. Plasma cells stay in the lymph or leave and pump out large amount of antibodies - a soluble form of their cell surface receptor A second type of activated T-cell is the T-helper cell that leaves the node to the infected area and interacts with macrophages and amplify inflammation Third type of T-cell is the cytotoxic T-Cell which kill cells infected with pathogen Remember 5 million lymphocytes are entering node every minute and only a few are activated in response to an infection.

50. Figure 1-19 Anatomy of immune function in the Spleen • Blood filtering organ - remove old/damaged red cells (red pulp) • Blood-borne pathogens e.g. malaria • White pulp (Immune system) - similar to lymph node (except pathogens enter and leave by blood)