CD274 and fibromyalgia: Next, we detected increased PD-1 in the SSCs of the fibromyalgia mice (Figure 5E, Tukey’s test, * p < 0.05, n = 6); this was inhibited by 2 Hz EA and PD-L1 administration (Figure 5E, Tukey’s test, # p < 0.05, n = 6).