To broaden our understanding of the regulation of HIV-1 transcriptome and the underlying alternative splicing events, we applied the recent development of ONT sequencing and quantified the steady-state level of all viral RNA isoforms in various infected cellular models (activated CD4+ T lymphocytes and Hela cells), in different production conditions (infection, transfection, in the presence of a wild-type or mutated spliceosomal machinery) and throughout a time course of primary CD4+ T cells HIV-1 infection. The gene discussed is CD4; the disease is HIV-1 infection.