Our laboratory has worked on the regulatory genes of HIV-1. We were particularly interested in understanding the mechanism of action of the tat regulatory gene. Tat is unique among transcriptional activators in that the gene product interacts with a secondary structural element at the 5' at the end of the RNA transcript. We are also interested in the role of HIV in malignancy, particularly B-cell lymphomas. We have shown that HIV can infect human B-cells in a CD4 independent manner.