Comparison of the cytokines between the OP and non-OP groups. The concentration of IFN-γ (a), TNF-α (b), IFN-α (c), IL-1β (d), IL-2 (e), IL-4 (f), IL-5 (g), IL-6 (h), IL-8 (i), IL-10 (j), IL-12P70 (k), and IL-17 (l) between the OP (n = 20) and non-OP (n = 20) groups was analyzed with unpaired t-test or nonparametric test (Mann-Whitney U test) according to the normality. Continuous variables in the normal distribution of the two groups were expressed as mean ± standard deviation (mean ± SD) and analyzed with the unpaired t-test. Continuous variables in the abnormal distribution were expressed as quartiles (50% (25%-75%)) and analyzed by the Mann-Whitney U test. P value < 0.05 was considered a significant difference.