Decrease in cell number. 1 Since CD4 T cells are essential for coordinated, effective immune function, the progressive loss of these cells underlies the immune deficiency that characterizes HIV infection. Clinicians have sought to arrest or reverse the decline in CD4 T cell count using antiretroviral drugs. Decrease in cell function. Moreover, while the decline in CD4 T cell number typically occurs over several years, impaired CD4 T cell function is seen from the earliest days of infection.
B cells produce inappropriate and excessive antibodies.
This inability to replace cell loss probably results from the damage HIV does to the bone marrow and thymus, which respectively serve as the sites of CD4 T cell production and maturation. Although research has shown that interleukin-2 increases CD4 T cell number, whether those cells are functional and clinically beneficial is not yet known. Two Phase III studies are now underway to determine the clinical effect, if any, of interleukin-2. If the trials end positively, interleukin-2 will become the first therapy directed specifically at increasing cell number and improving immune function. Increase in cellular activation.