Fig. 4.

Cryopreservation causes minor yet significant changes to proportions of CD39^+/−CD73^+/− T cells, while CD39^+/−CD73^+/− B cells remain relatively unaltered. a, b PBMCs, freshly isolated by Ficoll-Paque density gradient centrifugation and corresponding PBMCs cryopreserved for 1-, 3- and 6 months were labelled with fluorochrome-conjugated mAbs, and the proportions of a CD39^+/−CD73^+/− T cells and b CD39^+/−CD73^+/− B cells were determined by flow cytometry. Connected symbols represent individual donors (n = 11); P < 0.05 compared with corresponding freshly isolated PBMCs indicates significance; ns, no significances; paired two-tailed Student’s t test or Wilcoxon matched-pairs signed rank test