[AIDS and human lymphocytes]

HIV infection is no doubt the primary cause of AIDS. But the relationship between HIV and its host lymphocytes is fairly complicated. It has become clear that the host range of the viruses varies according to the clinical stage of the patients from whom viruses were isolated. Besides, the cause or mechanism of cell killing by HIV infection is not well-known. The density of CD4 molecules on the cell surface can not simply explain the phenomena, such as the level of virus growth, killing mechanisms of lymphocytes and host range of the virus. It is quite interesting to analyse which gene of the virus determines the characteristics of the virus.