Protection of Lymphocytes from HIV by Lentiviral Vector Carrying Gene Combination of TRIM5α-HRH and microRNAs against CCR5
Gene therapy is a promising approach to HIV treatment. One strategy is to introduce antiviral genes into cells to render them resistant to HIV. Here, we evaluated the antiviral potential of a new anti-HIV lentiviral vector pT. This vector carries a combination of two identical artificial microRNAs mic13lg and TRIM5a-HRH gene. Two microRNAs downregulate CCR5 expression and thus can prevent penetration of R5-tropic HIV into the cell. We have confirmed that pT is able to effectively knockdown CCR5 in model cell line HT1080 CCR5-EGFP, as well as in primary lymphocytes. TRIM5a-HRH provides the second line of defense against R5- and X4-tropic HIV by binding viral capsid after virus entry. Indeed, X4-tropic HIV replication rate decreased more than 1 000 fold in SupT1 cell line carrying 4 copies of pT vector per cell. pT production and CD4+ transduction conditions were optimized in order to test pT antiviral activity on primary human CD4+ lymphocytes. We achieved 28% transduction efficiency for pT. Cells viability was significantly higher in pT modified cell culture compared to control after infection with R5-tropic HIV. However, inhibition of HIV replication was not complete. The most likely reason is insufficient percent of modified cells in culture. Therefore, we will focus on finding an optimal CD4+ culture enrichment for modified cells to suppress HIV replication more efficiently.