1 / 26

Innate Defenses

Innate Defenses. External defense skin, etc. pH=3-5. Mucus Membranes. Internal Defense: Phagocytosis. Phagocytic cells. Migrate OUT of the blood when the sense differences in concentration of certain chemicals  engulf bacteria, dead cells, etc…. Natural Killer Cells.

sherrylm
Télécharger la présentation

Innate Defenses

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Innate Defenses External defense skin, etc.. pH=3-5

  2. Mucus Membranes

  3. Internal Defense: Phagocytosis Phagocytic cells Migrate OUT of the blood when the sense differences in concentration of certain chemicals engulf bacteria, dead cells, etc….

  4. Natural Killer Cells Recognize surface molecules on abnormal cells (cancerous or virus infected)

  5. Inflammatory response Swelling Pin Skin surface Bacteria Phagocytes and fluid move into area Phagocytes Chemical signals White blood cell Blood vessel Tissue injury; release of chemical signals such as histamine Phagocytes (macrophages and neutrophils) consume bacteria and cell debris; tissue heals Dilation and increased leakiness of local blood vessels; migration of phagocytes to the area 2 3 1 link

  6. Pin Skin surface Fig. 24-2a Bacteria Chemical signals White blood cell Blood vessel Tissue injury; release of chemical signals such as histamine 1

  7. Swelling Phagocytes and fluid move into area Fig. 24-2b Dilation and increased leakiness of local blood vessels; migration of phagocytes to the area 2

  8. Phagocytes Fig. 24-2c Phagocytes (macrophages and neutrophils) consume bacteria and cell debris; tissue heals 3

  9. Lymphatic system -includes vessels (with valves) -fluid (lymph) -organs Important cells are T lymphocytes and B lymphocytes These cells are involved in specific immunity “immune response”

  10. Acquired Immunity (the immune response) Is highly specific • Produces antibodies in response to specific antigens • Antigens may be molecules on • Bacteria, viruses, protozoa, worms, transplanted organs • Both B and T lymphocytes have receptors on membrane that recognize different antigens

  11. Cell-mediated immune response Humoral immune response Bone marrow Stem cell Thymus Via blood Fig. 24-5a Immature lymphocytes Antigen receptor Antigen receptor B cell T cell Via blood Lymph nodes, spleen, and other lymphatic organs Final maturation of B and T cells in lymphatic organ

  12. B cells -mature in bone - produce antibodies -antibodies float through the blood, recognizing and attaching to antigens T cells -mature in thymus -do not produce antibodies -”killer cells” Both B cells and T cells can produce memory cells

  13. Cell-mediated immune response Humoral immune response Bone marrow Stem cell Thymus Via blood Fig. 24-5a Immature lymphocytes Antigen receptor Antigen receptor B cell T cell Via blood Lymph nodes, spleen, and other lymphatic organs Final maturation of B and T cells in lymphatic organ

  14. Primary Immune Response T cells are selected B cells are selected -antibody producing plasma cells are produced Person feels ill while these cells are produced Symptoms diminish as these cells do their job

  15. Secondary Immune Response Response is much faster Memory cells are activated -tend to have a stronger response than the primary

  16. B cell (plasma cell) Fig. 24-17a Mast cell Antigenic determinant Histamine 2 Antibodies attach to mast cell Allergen (pollen grain) enters bloodstream B cells make antibodies 1 3 Sensitization: Initial exposure to allergen

  17. Fig. 24-17b Histamine is released, causing allergy symptoms Allergen binds to antibodies on mast cell 4 5 Later exposure to same allergen

  18. Allergies Hypersensitivity to environmental antigen (allergen) Antibodies attach to mast cells pollen bridges the gap causing degranulation Histamine & other Inflammatory agents released

  19. Active immunity results from natural recovery from infections vaccinations Passive immunity Receive antibodies from someone else -IgG anitibodies cross placenta -breast milk -shots (rabies treatment)

  20. Transfusions/transplants ABO blood group -IgM doesn’t cross placenta Antibodies produced against bacterial antigens which are very similar rH factor -IgG  crosses placenta

  21. Tissue graphs/ organ transplants Give drugs that suppress cell mediated immunity Bone marrow transplants Risk of graft vs host reaction Donor lymphocytes attack host cells

  22. Anaphylactic shock Acute reaction to allergen Massive dilation of blood vessels -drop in blood pressure Counteracted by epinephrine

  23. Autoimmune diseases Immune system doesn’t recognize “self” and attacks MS Insulin dependent diabetes

  24. AIDS HIV infection of cells require CD4 -found on T cells Is a retrovirus Antibodies are ineffective because -provirus gives it “invisibility” -rapid rate of mutation -Helper T cells decrease -secondary infections Drug treatments slow viral replication -AZT (reverse transcriptase inhibitors) -protease inhibitors

More Related