CD274 and myeloid sarcoma: In order to investigate whether unstimulated or Resiquimod-stimulated pDCs from MS patients were enriched in the P3 subpopulation, we measured the frequency of PDL-1+ CD80− (P1), PDL-1+ CD80+ (P2), and PDL-1− CD80+ (P3) within PBMC in both healthy donors and MS patients.