7/23/2019 J3 - Immunity

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1. Macrophage performs phagocytosis on the incoming bacteria. They break down the body of the pathogen except for itsantigen, which the macrophage will use to display upon their cell surface membrane. This is called antigen presentingmechanism, to display a specific antigen on the cell surface membrane so that it can be recognized by another cell.

2. T-helper immature! come from a specific precursor T-lymphocyte from the thymus gland. This precursor T-lymphocyte,takes in a specific antigen and becomes acti"ated. They will di"ide to make # subtypes of T cells$ T-helper cells acti"ate %cells!, T-cytotoxic cell become T-killer cells! and T-suppressor cell you don&t effing need to know!. This T-helper cellcarries a receptor that is specific to one antigen which the precursor T-lymphocyte was acti"ated to earlier. 'emember, at thisstage, the T-helpers are not ready to di"ide yet until they are acti"ated by the macrophage.

#. 'emember the macrophage earlier has displayed the right antigen on its surface( )ow the T-helper also carries thereceptor that recognizes the same antigen as well. *o now what happens( The T-helper and the macrophage will bind to eachother because their receptors are compatible to each other. +nce they bind, macrophages will release cytokines to the T-helper cells so that they will become acti"ated. +nce they are acti"ated the outcome will be$

a! ll T-helper cells will di"ide rapidly by mitosisb! ll the clone T-helper cells will be specific to one antigen only

)ow these acti"ated T-helper cells can do the following$a! cti"ate % cells

b! *ecrete cytokines to stimulate macrophages to induce more phagocytosis.

. The %-lymphocytes at this time are immature, means they are not ready to di"ide by mitosis yet. %ut what they can do is toingest a specific antigen and their receptors become specific to one antigen. )ow the acti"ated T-helper cells can bind tothese %-lymphocytes because their receptors are specific to the same antigen. %ut once they bind, the T-helper cells canrelease cytokines to the %-lymphocytes and acti"ate them. +nce they are acti"ated the outcome will be$

a! ll %-lymphocytes cells will di"ide rapidly by mitosisb! ll the clone %-lymphocyte cells will be specific to one antigen only

. )ow the %-lymphocytes will di"ide rapidly and create more clones. Their clones are di"ided to two groups basically. Theyare the %-memory cells and the plasma cells. The plasma cells will secretes specific antibodies that target one antigen.

7/23/2019 J3 - Immunity

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