IMMUNOLOGY

Complement, we can put holes in pathogens also

Human antibody. How can we make 100s of millions of different antibodies with only thousands of genes if the general rule is one gene per protein? How are antibodies able to distinguish self from other?

	Brad Pitt
	A basic tutorial on immunology
	Tutorial and a Game from Nobel Prize site,
	A course on vaccination

Two Important Proteins

IgG home page

IgG

MHC

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subunits

signaling sugars

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viral peptide

T-cell b7 recognition

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A Simplified View of Immune Cells

Several types of blood cells are part of our immune system. Follow these links to look at the response to a splinter on a cellular level. The response includes B cells, macrophages, Helper T cells and Killer T cells. The interaction of B Cells, T Cells and macrophages is seen in this nice photo and animation of an immune response to a bacterium.

B Cells

Each B Cell makes a single type of antibody. Because of gene splicing and recombination, hundreds of genes can make hundreds of million different kinds of antibodies. Each B Cell displays on its surface the antibody it makes. In the fetus, self reacting B Cells die (apoptosis). During an allergic response, in response to Helper T Cell messages (cytokines); B Cells that can bind, multiply and occasionally mutate. As an infection proceeds the B Cells with the tightest binding are preferentially replicated so that there is an evolution of ever more tighter binding. The antibodies made either kill the target directly or they mark it for destruction by complement, Killer T Cells or macrophages. Following the infection the antibodies and memory B Cells are stored in strategic places to protect against future infections.

Helper T Cells (CD4)

Similar to B Cells, except instead of making antibodies, they release signals (cytokines) such as interferon, Interleukin (IL-1), and Tumor Necrosis Factor (TNF). These message molecules coordinate the immune response by controlling the life, death, recruitment and multiplication of various cell lines as well as other aspects of inflammation. Memory T Cells are also stored following an immune reaction.

Killer T Cells (cytotoxic T cells, CD8)

Some infectious agents can avoid the antibody attack by hiding inside our cells. The MHC (major histocompatability complex) displays pieces of all proteins found within a cell. Cells that display foreign proteins are either infected or mutated and are marked for destruction by the Killer T Cells These cells can kill a target several ways including the use of nitric oxide and super oxide, or by the initiation of apoptosis (cell suicide). Sometimes bacteria fight back turning the T Cell's weapons against itself.

Macrophages

Amoeba like cells that devour foreign matter. They will display fragments of proteins that they have eaten to alert the Helper T Cells to possible pathogens.

mast cells and dust mites

Jenner

The memory cells make immunization possible. Polio is disappearing much as small pox before it did as a result of immunizations.(small pox hasn't entirely vanished)

Many of you haven't had german measles because of immunizations

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The growing need for organ transplants may be solved by making pig organs immunocompatible with people, but this raises the risk of the introduction of new viruses into human poputlations.

Decrease in diseases due to vaccination