AP Biology Immune Systems Part 1 Glycolipids and

AP Biology Immune Systems Part 1

Glycolipids and Glycoproteins of the ECM

Innate Immunity

Innate Immunity – Non-Specific Immunity • This is the immunity that you are born with. • Includes: – Skin and mucous membranes – Normal fauna: good bacteria that live on or in your body. – Sweat, saliva, tears, pepsin found in your stomach • The first line of defense against most environmental hazards and organisms that are trying to kill you.

Phagocyte “eating” a pathogen

Phagocytes – Non-specific Immunity • Phagocytes make up the second line of defense for your innate immunity • Phagocytes are specialized white blood cells that eat pathogens – Most phagocytes are neutrophils – general infantry – Monocytes: large WBCs in the blood fluids – Macrophages: large WBCs in the tissues • These locate and destroy dangerous organisms by following chemical trails

Macrophage (Neutorphil) Chasing Bacteria • https: //www. youtube. com/watch? v=Z_m. XDv ZQ 6 d. U

Inflammatory Immune Response - This first occurs when the body is attacked or injured Pathogen Pin Blood clot Macrophage Chemical signals Phagocytic cells Capillary Blood clotting elements Phagocytosis Red blood cell 1. 2. 3. 4. Capillaries dilate and venules constrict to trap blood in the area. Histamine is released by damaged cells – this calls in the troops Neutrophils rush to the site of the injury and begin killing foreign cells Macrophages and monocytes come in after the initial assault and clean up any remaining mess

Infected cell MHC I Antigen fragment Microbe MHC II Antigenpresenting cell Antigen fragment Class II MHC molecule Class I MHC molecule T cell receptor Cytotoxic T cell Helper T cell

Major Histocompatibility Complexes (MHCs) • These are special protein “hands” found on regular cells and specialized WBCs. • Two types exist: 1. Class I – All cells other than WBC’s possesses these. These are for telling WBC’s that a cell is infected when they are put on the surface holding an antigen (antibody generating particle) in the hand. a. The WBC knows to kill that cell because it is infected by the pathogen. 2. Class II – All WBC’s possess these. They show other WBC’s what to look for and kill. (They are like trophy hands. “Come see what I have killed so that you too may seek and kill it. ”)

Infected cell MHC I Antigen fragment Microbe MHC II Antigenpresenting cell Antigen fragment Class II MHC molecule Class I MHC molecule T cell receptor Cytotoxic T cell Helper T cell

Specific Immunity