CD4 and systemic sclerosis: Zol potently induced RP2 Vγ9δ2 T cells (but not CD4+ or Vδ1+ T cells) to produce TNFα, similar to its effect on a HD PBMC (Figure 2) whereas those of RP1 an SSc patient who had received Zol but no clinical APR did not secrete TNFα in response to Zol application in vitro.