B_T_2015_02_

(Michael S) #1

• Ability of B-cells to present antigen to helper T-cells is
a second function of B-cells in response to antigenic
stimulation other than differentiating into antibody-
secreting plasma cells.


• B-cells process antigen and present it to helper T cells
in the same way as described for dendritic cells and
macrophages.


• The activated T helper cells then activate B-cells and a
subgroup of T-cells called T cytotoxic cells in a specific
manner.


• The activated B-cells and T cytotoxic cells divide
repeatedly to produce clone of cells.


•    All the cells of a clone recognize the same antigen and
fight it, neutralize its action and eliminate it.

Immune response
• The specific reactivity induced in a host by an antigenic
stimulus is known as the immune response.
• It is of two types :


  • Primary immune response : It is the reaction of
    the body’s immune system to the first attack of
    microbes (antigens) and takes much longer time
    to develop.

  • Secondary immune response : It is the reaction
    of the body’s immune system to any subsequent

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