CD8A and bacterial infectious disease: Furthermore, elevated PRDM1 levels have been associated with exhausted cells having diminished polyfunctionality and increased expression of inhibitory receptors.13 Correspondingly, exhausted CD8+ T cells from individuals with bacterial infections, especially in mild cases, had notably higher expression levels of key transcription factors such as PRDM1 and PTPN6/11 compared to healthy donors (Supplementary Fig. 10a).