Question

How do T cells coordinate the specific humoral immune response. Then describe how T cells coordinate the specific cell mediated immune response. For both, be sure to discuss all receptors involved, interleukins, all cell interactions, and cell types.

Answer 1

Cell-Mediated Immunity-

This form of immunity is controlled by cytotoxic T cells and type 1 helper T cells (Th1)

The T cell is activated by antigen-presenting cells so that they mature being specific to the antigen. The pathogens destruction pathway is as follows-

a) Helper T cell secrete cytokines to guide cytotoxic T to destroy pathogens

b) Cytotoxic T releases granules of perforin and granzyme

c) These granules create a hole in the membrane of the pathogen

d) Helper T cell then produce protease that enters into the pathogen cell and induces apoptosis

Humoral Immunity

It is mediated by –

· B cells

· Antibodies

· Type 2 helper T cells (Th2)

· Eosinophils

Mast Cell

Type 2 helper T cells present antigens to immature B-cells which after proliferation produces antibodies that circulate through the body’s plasma.

Antibodies then bind to pathogens and opsonize them and hence neutralize the toxins

Mast cells and eosinophils sensitize antigens by circulating immunoglobin E (IgE) antibody. When antigen is detected, IgE binds to mast cells and eosinophils leading to degranulation and release of inflammatory mediators as an immune response against the antigen