HIV Tat protein increases Bcl-2 expression in monocytes which inhibits monocyte apoptosis induced by tumor necrosis factor-alpha-related apoptosis-induced ligand.
OBJECTIVE
To investigate the effect of HIV Tat protein on Bcl-2 expression in human monocytes, and observe apoptosis of Tat-stimulated monocytes induced by TNF-alpha-related apoptosis-induced ligand (TRAIL).


METHODS
Western blot was used to detect Bcl-2 expression in monocytes stimulated by HIV Tat protein, and Annexin V and 7-AAD staining were used to detect apoptosis of monocytes induced by TRAIL.


RESULTS
HIV Tat protein increased Bcl-2 expression in human monocytes in a dose-dependent manner. Annexin V staining showed that 51.54% of monocytes underwent apoptosis after being treated with 100 ng/ml recombinant TRAIL. When monocytes were prestimulated with HIV Tat, only 15.46% of monocytes underwent apoptosis. This effect can be inhibited by polyclonal anti-Tat serum. 7-AAD staining showed similar results.


CONCLUSIONS
HIV Tat protein increases Bcl-2 expression in monocytes which inhibited apoptosis induced by TRAIL. HIV Tat protein may play an important role in the mechanisms of HIV-persistent infection in monocytes.
Zheng
Lin
L
Department of Infectious Diseases, The First Affiliated Hospital, Medical School, Key Laboratory of Infectious Diseases of Chinese Ministry of Public Health, Zhejiang University, Hangzhou, Zhejiang, PR China.
Yang
Yida
Y
Guocai
Lu
L
Pauza
C David
CD
Salvato
Maria S
MS
D017304:Annexin A5 / Q000378:metabolism; D017209:Apoptosis; D015153:Blotting, Western; D002478:Cells, Cultured; D003609:Dactinomycin / Q000031:analogs & derivatives / Q000378:metabolism; D005434:Flow Cytometry; D005786:Gene Expression Regulation; D015696:Gene Products, tat / Q000502:physiology*; D019254:Genes, bcl-2 / Q000276:immunology*; D006678:HIV / Q000276:immunology*; D006801:Humans; D009000:Monocytes / Q000166:cytology / Q000276:immunology / Q000821:virology*; D013194:Staining and Labeling; D053221:TNF-Related Apoptosis-Inducing Ligand / Q000037:antagonists & inhibitors*; D054322:tat Gene Products, Human Immunodeficiency Virus
D017304:Annexin A5; D015696:Gene Products, tat; D053221:TNF-Related Apoptosis-Inducing Ligand; D054322:tat Gene Products, Human Immunodeficiency Virus; D003609:Dactinomycin; C025942:7-aminoactinomycin D