HIV particle production is accompanied by mRNA upregulation of CD44 and endocytic molecules. (A) Differential gene expression upon reactivation. J1.1 and U1 cells were either unstimulated or stimulated with 50 ng/ml TNF-α (gray columns). For comparison, uninfected Jurkat and U937 cells were similarly stimulated (white columns). Expression of each gene was quantified by qRT-PCR and normalized to the level of GAPDH. The fold increase of expression of each gene upon stimulation was shown. *, p < 0.01; **, p < 0.05. Expression levels of HIV-1 gag and tat mRNAs were quantified using specific primers (HIV-1 nucleotide positions 701–720 and 787–806 for gag and 5965–5987 and 8389–8411 for tat, respectively) (black columns). (B) Differential gene expression upon acute infection. Jurkat and U937 cells were infected with HIV-1 and subjected to qRT-PCR. The fold increase of each gene expression upon infection was shown (gray columns). *, p < 0.01; **, p < 0.05. (C) Protein expression of J1.1, U1, Jurkat, and U937 cells. TNF-α stimulation and infection were similarly performed. Cells were subjected to Western blotting using anti-CD44, anti-CD63, anti-HRS, anti-actin, anti-HIV-1 p17MA, and anti-p24CA antibodies.