Evaluation of relative promoter strengths of the HIV-1-LTR and a chimeric RSV-LTR in T lymphocytic cells and peripheral blood mononuclear cells: promoters for anti-HIV-1 gene therapies.
Gene therapy approaches for human immunodeficiency virus type 1 (HIV-1) infections focus on the transfer of critical genetic elements into CD4+ T lymphocytes and CD34+ stem cells. Ideally, expression of the anti-HIV-1 gene constructs should be induced during early stages of infection to combat high turnover of the replicating virus. In this study, we investigated the activity of two promoters, HIV-1 long terminal repeat (HIV-1-LTR) and Rous sarcoma virus (RSV) LTR fused with the transactivation response element (TAR) from the HIV-1-LTR (ie RSV-TAR) in presence of Tat, the major HIV-1 transcriptional transactivator and an early gene product in HIV-1 infection. Comparative expression from both of these plasmids was analyzed by measuring expression of a reporter gene, chloramphenicol acetyltransferase (CAT), after transfection of the promoter-CAT constructs and a Tat-expressing plasmid into CEM T lymphocytic cells and peripheral blood mononuclear cells (PBMC). The HIV-1-LTR could be transactivated by Tat in both unstimulated and stimulated cells. Although the RSV-TAR had a relatively high basal level of expression, Tat transactivation of this chimeric promoter occurred only in unstimulated cells. These results suggest that the HIV-1-LTR may be a better promoter for therapeutic gene expression in anti-HIV-1 intracellular immunization approaches.
Mukhtar
M
M
Dorrance H Hamilton Laboratory, Department of Medicine, Jefferson Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA.
Duan
L
L
Bagasra
O
O
Pomerantz
R J
RJ
D001358:Avian Sarcoma Viruses / Q000235:genetics*; D015500:Chloramphenicol O-Acetyltransferase; D005069:Evaluation Studies as Topic; D015696:Gene Products, tat; D017930:Genes, Reporter; D015316:Genetic Therapy; D015658:HIV Infections / Q000628:therapy; D016325:HIV Long Terminal Repeat / Q000235:genetics; D015497:HIV-1 / Q000235:genetics*; D006801:Humans; D007963:Leukocytes, Mononuclear; D011401:Promoter Regions, Genetic; D012091:Repetitive Sequences, Nucleic Acid / Q000235:genetics*; D013601:T-Lymphocytes; D015533:Transcriptional Activation; D054322:tat Gene Products, Human Immunodeficiency Virus
D015696:Gene Products, tat; D054322:tat Gene Products, Human Immunodeficiency Virus; D015500:Chloramphenicol O-Acetyltransferase