Differential expression of chemokine receptors and CD95 in porcine CD4+ T cell subsets

Among other differences, naïve and memory T cells show distinct migratory patterns and susceptibility to CD95-mediated cell death. We have recently characterised in the pig two subsets of CD4+ T cells, based on the expression of the 2E3 marker, that display phenotypic and functional features of naïve (CD4+2E3+) and effector/memory (CD4+2E3−) T cells. In this study, we have analysed the expression of several chemokine receptors, as well as the distribution of CD95 antigen (APO-1/Fas) in these CD4+ T cell subsets. CD4+2E3− T cells express high levels of CXCR3 and CCR4 transcripts but not of CCR7. On the contrary, CCR7 is clearly detected in CD4+2E3+ T cells, whereas CXCR3 and CCR4 are negative or present at trace levels. These subsets also differ in the expression of CD95 antigen, being CD95 positive cells significantly more abundant in the CD4+2E3− cell subset. These findings, although based on a small number of animals, fit well with those reported for naïve and memory CD4+ T cells in humans.