Question

How is CD4 count involved in monitoring HIV infection? What is another laboratory method to monitor the disease?

Answer 1

CD4 is a glycoprotein found on the surface of helper T cells. Helper T cells are the key to activate cell mediated (cytotoxic T cell) as well as humoral immunity (B cell). The virus of AIDS known as HIV infects the helper T cells and destroy them. Number of CD4 counting(CD4+ cell counting) hence decreases in case of HIV infection. When the number of CD4 drops below 200 it is supposed that the patient have the symptoms of AIDS. The normal range of CD4 count is between 500-1500.

The another method is the serological testing. For this test serum of the patient is collected. If the patient contains the HIV antigen in the serum body must secrets antibody for the antigen. Hence we can perform an ELISA test. The colour change indicates to the presence of antigen. In case of inherited HIV infection, this serological testing may not effective.