By Ms. Kostiuk from Microbiology department

1. Immunology Nonspecific defense

4. Resistance For species For individual Nonspecific (innate) Specific (acquired) Barriers and physiological factors Cell factors Chemical factors

6. The second line of defense The first line of defense includes any barrier that blocks invasion at the portal of entry.

7. The second line of defense The second line of defense is a slightly more internalized system of protective cells and fluids that includes inflammation and phagocytosis .

8. The third line of defense The third line of defense is specific immune factors ( antibodies and T-lymphocytes )

11. The ciliary defense of the respiratory tree Cilia

13. Cells that take part in immune response Participate in immunological responce In lymphoid tissues; also in the circulation Lympho-cytes Phagocytosis and digestion of engulfed materials, can participate in killing foreign cells that are not engulfed MPh present in all tissues and in of vessels, monocytes are less mature circulation form Monocyte, macrophage Mononuclear phagocytes Phagocytosis and digestion of engulfed materials Most in circulation, few in tissues Neutrophils Participate in inflammatory reaction More are in circulation, few in tissues Eosinophil Release histamine and other mediators of inflammation Basophils in circulation; mast cells present in most tissues Basophil Granulosytes Functions Location in body Cell type

16. Macrophages attacking bacteria and yeast

17. Phagocytosis and intracellular digestion

20. Uncompleted phagocytosis of gonococci and meningococci

24. Antiviral action of interferon 1. The binding of a virus to the receptors of an infected cell sends a signal into the cell nucleus that activates the genes coding for interferon. 2. Interferon is synthesized and secreted into the extracellular spaces . 3. IFN enters into uninfected cell and activates gene complex that code for another protein 4. This synthesized protein interfered with the multiplication of viruses.

25. Characteristic of human interferons + + + Activation of natural killer cells ++ - - Macrophage activation + +++ +++ Antiviral activity 20-25 kD 16-26 kD 16-26 kD Molecular mass - + + Resistance to рН 2,0 1 1 More then 20 Quantity of variants Antigens, mitogens Viruses, interferonogens Viruses, interferonogens Inductor γ - interferon β - interferon α - interferon Features

28. The complement cascade. Classical scheme of activation

29. Electron micrograph of a cell reveals multiple puncture sites Puncture sites Enzyme complex

30. Complement proteins C5 C6 C7 C8 C9 Membrane attack components (common to both pathways) C1 C4 C2 C3 Properdin Factor D Factor D Factor C3b Mg Classical (initial portion) Rapid and efficient Alternative or properdin (initiatial portion) Slower and less efficient Components Pathway

32. Some important nonspecific antimicrobial factors Cell lysis, opsonization and chemotaxis Produced by macrophages, lymphocytes, and liver hepatocytes Complement system Interferes with the multiplication of viruses and bacteria; immune regulation Leukocytes and tissue cells Interferon Kills a variety of microorganisms; important within neutrophils Leukocytes, saliva, and other Peroxidase Attacks cytoplasmic membrane; active against Gram-positive bacteria Serum, leukocytes Beta-lysin Destroys bacterial cell walls Most body fluids; also within phagocytes Lysozyme Effects Source Factor