Question

Describe how cytokines function in various immune processes including signal 3 of lymphocyte activation

Answer 1

Cytokines are peptides secreted by immune cells and helps in cell signalling. Interferons and interleukin are example of cytokines.
Cytokines binds to specific receptor on the cell surface and mediates the process of cell signalling. Cytokines can upregulate cell activity by increasing cell maturation, differentiation and cell growth or increasing cytokine cell receptors or increasing cytokine release from cell.
Cytokines can also lead to downregulation of a cell by suppressing cell activity through negative feedback.
– Cytokines are released from the antigen presenting cells. These cytokines act on the naive helper t lymphocytes and results in maturation and differentiation into mature helper t lymphocytes and memory cells.
–The helper t lymhocytes binds to the antigen presenting cells and secrete more cytokines.

– These cytokines act on the naive cytotoxic t cells and helps them grow and differentiate into mature cytotoxic t cells and memory cells. The mature cytotoxic t cells act on the infected cell and kills it.
– cytokines produced by mature helper t cells also activates the B lymphocytes.
– The b cells differentiates into plasma cells and memory cells.
– The plasma cells secrete antibodies against antigen and destroys it.