Different regulatory T-cells are induced upon interaction with Leishmania donovani.

Percentage of Tr1 (CD4⁺CD25⁻CD127⁻) and iTreg (CD4⁺CD25⁺CD127^low/−) cells among gated CD4⁺ cells (n = 10). Briefly, freshly isolated PBMCs were incubated with Sb^S and Sb^R-LD isolates and after day 2 and day 8 cells were stained and percentage of Tr1 and iTreg cells were analysed by Flow Cytometry. Lymphocytes were gated based on forward and side scatter profiles, and live cells were identified on the basis of exclusion of LIVE/DEAD Aqua dye (Invitrogen), followed by CD3⁺ and subsequently on CD4⁺ cells. A. CD4⁺ cells were further gated based on the expression of CD25 and CD127 to identify Tr1 (CD4⁺CD25⁻CD127⁻) and iTreg (CD4⁺CD25⁺CD127^low/−) populations. B–C. Percentage of Tr1 cells on day two and eight respectively, D–E. Percentage of iTreg cells on day two and eight respectively. Data were analysed by the Mann-Whitney test, and levels of significance are indicated by P values.