CD4 T-cell function assay using Cylex ImmuKnow and lymphocyte subset recovery following allogeneic hematopoietic stem cell transplantation

•ImmuKnow levels at 6 months post-alloHSCT were higher than 6 months before.•The levels were correlated with NK cell count at 6 months before.•Later than 6 months, the levels were correlated with CD4 T cell count.•The patients with acute GVHD or infection episode showed increased ImmuKnow levels.

We analyzed CD4 T-lymphocytes ATP levels along with lymphocyte subsets in 160 samples from 111 post-allogeneic hematopoietic stem cell transplantation (alloHSCT) patients. In patients with stable status, ImmuKnow levels changed over time and the 6-month post-alloHSCT levels were significantly higher than those tested within 6 months post-alloHSCT (P < 0.001). Although, ImmuKnow levels for acute graft-versus-host disease (GVHD) or infection episodes were not significantly different compared to those for stable alloHSCT, the levels were correlated with specific lymphocyte subpopulations at different times; the results within 6 months post-alloHSCT showed low positive correlation with natural killer cell count (r = 0.328) (P < 0.05) and the values tested later than 6 months post-alloHSCT were positively correlated with CD4 T cell count (r = 0.425) (P < 0.05). Two patients who developed acute GVHD and two who experienced an infection episode showed increased ImmuKnow levels in sequential tests. The combined test of ImmuKnow levels and lymphocyte subsets may be helpful for immune monitoring following alloHSCT.