Effects of HIV-1 Tat derived from central nervous system of a HIV-associated dementia patient on the activity of human umbilical vein endothelial cells / 中华实验和临床病毒学杂志

ABSTRACT

Objective@#BG-derived HIV-1 Tat protein from an HIV-associated dementia (HAD) patient was expressed in E. coli BL21(DE3) and purified in order to research the effects on human umbilical vein endothelial cells (HUVECs) activity.@*Methods@#The recombinant plasmid pGEX-KG-tat with HIV-1 tat stored in our laboratory was amplified by PCR. The PCR product was cloned into pET-32a-tat. The recombinant plasmid pET-32a-tat was transfected into E. coli, and Tat protein was expressed in BL21(DE3), which was induced by IPTG. Then it was purified by Ni-chelating chromatography column and gel filtration preloaded column, and identified by SDS-PAGE and Western blot(WB). The concentration was determined by BCA Kit. Different concentrations of Tat were added into HUVECs to detect their effects on cell activity by cck-8.@*Results@#The Tat with high purity was efficiently expressed in BL21 (DE3) and obtained by using the Ni-chelating chromatography column and gel filtration preloaded column. The concentration was 0.47 mg/ml by using BCA Kit. As the concentration of Tat increased, HUVECs activity decreased. There was no significant difference in cells viability between negative control with 100 ng/ml and 200 ng/ml group (P>0.05). There was significant difference in cells viability between negative control with 300 ng/ml, 400 ng/ml, 500 ng/ml and 1000 ng/ml group (P<0.05). But the difference between 300 ng/ml, 400 ng/ml, 500 ng/ml and 1000 ng/ml group was not statistically significant (P>0.05).@*Conclusions@#The HIV-1 Tat with biological activity was efficiently expressed in BL21 (DE3), and the activity of HUVECs was significantly decreased when the concentration reached 300 ng/ml.