~~~~~~~~~~~~~~~~~~~~~~~ http://main.uab.edu/show.asp?durki=44933
I. General information A. Immune system - physiological system to defend the body against foreign particles and infectious organisms 1. Lines of defense First - Skin, mucus membranes, temperature, and pH Second - phagocytic and antigen presenting cells (APC's) Third - Acquired immunity II. Components of the immune system A. Organs of the Immune System 1. Primary organs Bone - Specifically, the bone marrow. Site of differentiation Thymus - Site of T lymphocyte maturation 2. Secondary Organs Lymph nodes - House mature T and B lymphocytes Spleen - houses mature B and T lymphocytes. Site of Antigen presentation Tonsils Skin and Mucosa B. Cells of the Immune system 1. Antigen Presenting Cells (APC's) - macrophage, monocytes, neutophils, and eosinophils 2. Lymphocytes - B and T cells a. B lymphocyte - Functions in Humoral Immunity Antibody (Ab) structure and classes – Somatic Rearrangement Theory Explaining the Ab diversity Complementary Determining Region – Variable Paratope (Fab) Constant Region – Determines Immunoglobulin class (Fc) IgG, IgM, IgA, IgE, IgD b. T lymphocyte - Function in Cell mediated Immunity T-lymphocyte Differentiation and Selection TCR development - Positive Selection – Restrict to MHC recognition Negative Selection – Restrict to Self-tolerance CD8-T lymphocytes - cytotoxic T-cell - recognized MHC I receptors CD4-T lymphocytes - Helper T-cell - recognize MHC II receptors Ts Lymphocyte – Suppress immune action 4. Natural Killer Cells - Auto-programmed to kill foreign cells and cancerous cells. C. Chemical Mediators - Cytokines - small proteins, secreted by immune cells, control the type and strength of the immune response. Approx. 25 known distinct types 1. Types 2. Mechanisms a. autocrine b. paracrine c. endocrine ~~~~~~~~~~~~~~~~~~~~~~~~~~~ http://www.thewellproject.org/Treatment_and_Trials/First_Things_First/Understanding_the_Immune_System.jsp T Cells Once antigens are processed and displayed on the surface of macrophages, they can be recognized by helper T cells (also known as CD4 cells). When CD4 cells “see” the antigens displayed, they get busy and put the word out to other immune system cells. In other words, these cells ***coordinate and direct the activity of other types of immune cells***—such as killer T cells, B cells, and macrophages—calling them into action to fight the intruder. CD4 cells produce many different cytokines in order to communicate effectively with other immune system cells. Killer T cells directly **attack and destro** (kill) cells infected by viruses as well as abnormal cancerous cells. Yet another type of T cell, called suppressor T cells, **calls off the immune system attack once the invader is conquered**. (This is to make sure the killer cells don’t go overboard, and relax once their job is done.) Both killer T cells and suppressor T cells are also known as CD8 cells. > JH> Garnet, will you explain for us what the CD4 and CD8 function are? -- The Silver List is a moderated forum for discussing Colloidal Silver. Instructions for unsubscribing are posted at: http://silverlist.org To post, address your message to: [email protected] Silver List archive: http://escribe.com/health/thesilverlist/index.html Address Off-Topic messages to: [email protected] OT Archive: http://escribe.com/health/silverofftopiclist/index.html List maintainer: Mike Devour <[email protected]>
