CD4 and myeloid sarcoma: In the second study, when PBMCs from ten irradiated patients were compared with the same number, also with MS, who did not receive the intervention, there was no association of phototherapy with the frequency of CD4+ or CD8+ T cells, Tregs or T follicular regulatory cells as a percentage of PBMCs, irrespective of whether Tregs were defined as CD4+FoxP3+, CD4+CD25+CD127lo or expressed differing levels of Helios (8) (Table 1).