In order to clarify the mechanism of inhibition of human neutrophil peptide-1 （HNP-1） on human immunodeficiency virus type 1（HIV-1）, CD4+ cells were used as the target cells for acute infection with HIV-1, and exp...In order to clarify the mechanism of inhibition of human neutrophil peptide-1 （HNP-1） on human immunodeficiency virus type 1（HIV-1）, CD4+ cells were used as the target cells for acute infection with HIV-1, and experiments were performed separately with the interaction of different concentrations of HNP-1 with free virus particles, un-infected and infected CD4+ cells. The activity of reverse transcriptase （RT） in the supernatant of cell cultures of different lots of experiments were then assayed accordingly, and the toxicity effect on human lymphocytic cells MT4 was measured by MTT assay. The experimental results showed that pre-incubation of HNP-1 with the concentrated stock of virus could block the binding of virus to target cells with EC50 of 2.49 μg/ml, while pre-treatment of CD4+ cells with HNP-1 prior to inoculation could reduce the ability of cells to bind virus with EC50 of 20.7 μg/ml. In addition, When culturing the infected CD4+ cells in the continuous presence of various concentrations of HNP-1 added immediately after infection, HNP-1 exhibited modest inhibitory effect on viral replication with reduced RT activities in comparison with those of the control group （P<0.05 at 100 μg/ml of the highest concentration）. No cytotoxicity effect of HNP-1 was observed as demonstrated by MTT assay. These results indicate that HNP-1 exerts anti-HIV activity by at least two levels: direct inactivation of virus particles and effect on the ability of target cells to bind with viruses. The evaluation of two parameters, inhibitory effect and the cytotoxicity renders HNP-1 an available candidate for anti-HIV therapeutic agent.展开更多
文摘In order to clarify the mechanism of inhibition of human neutrophil peptide-1 （HNP-1） on human immunodeficiency virus type 1（HIV-1）, CD4+ cells were used as the target cells for acute infection with HIV-1, and experiments were performed separately with the interaction of different concentrations of HNP-1 with free virus particles, un-infected and infected CD4+ cells. The activity of reverse transcriptase （RT） in the supernatant of cell cultures of different lots of experiments were then assayed accordingly, and the toxicity effect on human lymphocytic cells MT4 was measured by MTT assay. The experimental results showed that pre-incubation of HNP-1 with the concentrated stock of virus could block the binding of virus to target cells with EC50 of 2.49 μg/ml, while pre-treatment of CD4+ cells with HNP-1 prior to inoculation could reduce the ability of cells to bind virus with EC50 of 20.7 μg/ml. In addition, When culturing the infected CD4+ cells in the continuous presence of various concentrations of HNP-1 added immediately after infection, HNP-1 exhibited modest inhibitory effect on viral replication with reduced RT activities in comparison with those of the control group （P<0.05 at 100 μg/ml of the highest concentration）. No cytotoxicity effect of HNP-1 was observed as demonstrated by MTT assay. These results indicate that HNP-1 exerts anti-HIV activity by at least two levels: direct inactivation of virus particles and effect on the ability of target cells to bind with viruses. The evaluation of two parameters, inhibitory effect and the cytotoxicity renders HNP-1 an available candidate for anti-HIV therapeutic agent.
