PROTECTION OF PRIMARY HUMAN T-CELLS FROM HIV-INFECTION BY TREV - A TRANSDOMINANT FUSION GENE

Gene therapy is one of several approaches that are being tested in the search for an effective anti-human immunodeficiency virus (HIV) treat ment, In this strategy, a ''protective'' gene would be introduced into target cells, rendering them relatively resistance to the virus-induc ed cytopathicity. Tat and Rev are viral proteins essential for HIV gen e expression. Tat increases viral gene transcription and Rev is respon sible for the nuclear export of mRNA encoding structural viral protein s. A fusion protein (Trev) was constructed, joining Tat and Rev transd ominant mutant gene sequences, previously, we showed that Trev inhibit s both Tat and Rev activities in Jurkat T cells. To determine whether Trev could inhibit HIV replication in primary cells, we transferred th e trev gene to peripheral blood lymphocytes and challenged them with d ifferent HIV strains, Levels of HIV p24 antigen (Ag) were reduced 4- t o 15-fold in cultures of Trev-CD4(+) T cells infected with two HIV pri mary clinical isolates and were not detectable in cultures infected wi th HIV strains NL4-3 and SF2. In contrast, cultures of nontransduced C D4(+) T cells infected with the same viruses had levels of HIV p24 Ag up to 10 ng/ml. Trev-transduced CD4(+) T cells demonstrated increased survival following HIV challenge for the length of the experiments (30 days), We did not observe rapid emergence of Trev-resistant HIV in ou r cultures. Following HIV challenge, cell-associated Trev protein was increased, supporting the hypothesis that cells surviving Trev express ion provided a cell survival advantage. This work showed that Trev was able to inhibit HN replication in primary CD4(+) T cells, and, theref ore the trev gene could be a candidate for gene therapy against HIV.