Proliferative response of Vδ1 and Vδ2 T lymphocytes to microbial antigens. PBMCs obtained from either Hds (n = 10) or HIV-1–infected patients (n = 30) were stained with CFSE and cultured for 7 days in the presence of IPP, PPD, CMV, PC, or Ca and rIL-2 was added on day 4. Vδ1 or Vδ2 T cells were identified by staining with the PE-conjugated A13 or BB3 mAbs, respectively. (A) Percentage of proliferating cells evaluated as red cells with reduced green fluorescence intensity on Vδ1 or Vδ2 gated T lymphocytes in Hds (Ai) or HIV-1–infected Pts (Aii). None indicates PBMCs cultured in the absence of antigens. Mean ± SD from 10 Hds (Ai) and 30 Pts (Aii); *P < .01 versus none. (B,C) Computerized analysis with the ModFit program, showing the percentage of Vδ1 or Vδ2 T lymphocytes in third or fourth generation (Bi: Hds; Bii: Pts) or the precursor frequency (C) on day 7 of culture with Ca or PPD. Mean ± SD from 10 Hds and 30 Pts. (B) *P < .01 versus parental population. (C) **P < .01 versus Hds.