FIG. 2.

Evaluation of interleukin (IL)-2 and NFAT2 levels in T helper cells cocultured with Treg cells from feline immunodeficiency virus (FIV)⁻ and FIV⁺ cats. CD4⁺CD25⁻ and CD4⁺CD25⁺ T cells were purified as described in Materials and Methods. CD4⁺CD25⁻ cells were stimulated with Con A (5 μg/ml) for 1 h and autologous CD4⁺CD25⁻ cells (control, white bars) or CD4⁺CD25⁺ cells (suppressor cells, gray bars) were added to the culture. Relative IL-2 and NFAT2 mRNA expression levels were assessed using real time RT-PCR and culture supernatant was collected for IL-2 ELISA. (a) CD4⁺CD25⁻ IL-2 mRNA was reduced in FIV⁻ cats (left plate) after a 24 h coculture with autologous CD4⁺CD25⁺ cells. (b) CD4⁺CD25⁻ IL-2 production was reduced in FIV⁻ (left plate) and FIV⁺ (right plate) cats after a 48 h coculture with autologous CD4⁺CD25⁺ cells. (c) CD4⁺CD25⁻ NFAT2 mRNA expression levels appear unaltered by autologous CD4⁺CD25⁺ coculture. For IL-2 and NFAT2 mRNA, expression of the housekeeping gene GAPDH was used as the control, and results were calculated as 2^–ΔΔCt. Error bars indicate the mean+SEM for each time point. Data are representative of four independent experiments; asterisks=p<0.05.