Transcriptional analysis of HIV-specific CD8 + T cells shows that PD-1 inhibits T cell function by upregulating BATF

The inhibitory receptor programmed death-1 (PD-1) is upregulated on exhausted CD8+ T cells in HIV-infected individuals. Quigley et al. analyzed the transcriptional profile induced by PD-1 ligation and report that a transcription factor, BATF, is upregulated by PD-1 signaling and has a key role in PD-1–mediated inhibition of T cell function.