SUMMARY
Remarkable advances have been made in research on HIV-1 since the discovery of the virus, and the functions of viral proteins are rapidly being uncovered. However, many of the studies on the mode of virally induced cell death have thus far resulted in contradictory conclusions, partially due to technical difficulties and interpretation of data, as discussed above.
Moreover, consensus on the roles of viral proteins in HIV-1 killing has not been reached, although numerous reports have assigned molecular functions to HIV-1 proteins during the viral life cycle. Better knowledge of how HIV-1 kills T lymphocytes is likely the key to understanding AIDS pathogenesis and is, therefore, crucial in developing new therapeutic strategies. Further study is necessary to establish a relationship between viral protein functions and cytopathicity, which should lead to an elucidation of the mechanism by which HIV-1 kills CD4+ T cells.ACKNOWLEDGMENT
A tremendous amount of work was published in this field, making it impossible to discuss many important studies. The papers cited here make up only a representative and not comprehensive group of publications in this area of research. The authors apologize to the many fine investigators whose work could not be cited for lack of space. We thank Diane Bolton and members of Lenardo Lab for helpful discussions. K.S. is a JSPS research fellow for Japanese biomedical and behavioral research at NIH.
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