Figure 6.

Decrease of CD56^bright NK cell frequency following brief exercise is not affected by 24 h of in vitro IL-2 treatment. (A) Pre-exercise and post-exercise NK cells (n = 7) or PBMC (n = 5) were isolated and stained immediately with a mix of anti-CD3/anti-CD56 Ab or anti-CD3/anti-CD56/anti-CD16, respectively. The frequency of CD56^dim versus CD56^bright NK cells was then quantified by flow cytometry. Shown are the mean percentages of CD56^bright NK cells detected in 12 different donors. (B) Pre-exercise and post-exercise NK cells were isolated and stimulated with 50 U/mL IL-2 or (C) 500 U/mL IL-2 for 24 h. The frequency of CD56^bright NK cells of seven different individuals pre- and post-exercise was determined. Significant differences are indicated in the graphs as follows: **p < 0.01 (paired two tailed student’s t test).