Analysis of viral transcripts of Human T-cell Leukemia Virus type 2 (HTLV-2) in human T- and B- infected cells and PBMCs from infected subjects

Recent studies carried out on HTLV-1-infected cells have provided information on the relative abundance and timing of expression of different viral transcripts. In the case of HTLV-2, information on the profile and temporal regulation of viral gene expression is still incomplete. To address this point, we set up a splice-junction-specific real-time RT-PCR to evaluate the quantitative level of individual HTLV-2 transcripts. Results obtained led to the quantitation of all the HTLV-2 mRNAs described so far, namely gag/pol, env, tax/rex, p28,p22/p20rex-1, p28,p22/p20rex-2 and p10/p11. This analysis was carried out first on chronically infected lines: T-cells infected with the HTLV-2A subtype (Mo-T and C344) or B-cells infected with the HTLV-2B subtype (BJAB-Gu cells). Results showed different levels of expression of env and tax/rex transcripts in T- and B-cells. The expression profile and kinetics of expression of the different transcripts was analyzed in PBMC obtained ex vivo from infected individuals and cultured for several hours. Current experiments are also aimed at testing the possible connections between the pattern of HTLV-2 gene expression and the different phases of the cell cycle.