Fig. 3

Effects of surgery on monocyte and MO-MDSC marker expression in placebo-and TXA-treated patients. The effects of surgery on the expression immune-stimulating and immunosuppressive markers were evaluated on monocyte subsets and MO-MDSC in placebo-treated and TXA-treated patients using flowcytometry. Classical monocytes displayed a reduction of HLA-DR (B), yet an increase of TNFR2 (F) and of CD83 (G) on POD-3 in placebo-treated patients. A reduction of HLA-DR was also evident on intermediate monocytes on POD-1 and POD-3 (I), which in turn showed an increase in PD-L1 expression (K). Non-classical monocytes showed enhanced expression of CD83 on POD-3 (U). In the TXA group, a postoperative decrease in CD86 (A) HLA-DR (B), CCR4 (C) and PD-L1 (D) on classical monocytes could be observed, while an increase in TNFR2 (F) and CD83 (G) was noticeable. For intermediate monocytes we also obtained comparable results to the placebo group with decreased surface expression of HLA-DR (I) and increased TNFR2 (M). On non-classical monocytes TXA-treated patients displayed a significant reduction in HLA-DR (P) and TNFR2 expression (T), yet an upregulation of CCR4 (Q). On MO-MDSC CD86 (V), PD-L1 (X) and CCR7 (Y) were downregulated, and TNFR2 (Z) and CD83 (a) expression enhanced, postoperatively. None of the other parameters was changed postoperatively in the placebo- or TXA treated patients. Data are expressed as mean ± standard error of the mean. Placebo: n = 4, TXA n = 14. *p = 0.05, **p = 0.01, ***p = 0.001, ****p = 0.0001, comparisons with preOP, repeated measures one-way ANOVA with Dunnett’s correction test for multiple comparisons. preOP: pre-operative, EOS: end of surgery, POD-1: post-operative day 1, POD-3: post-operative day 3, monos: monocytes, MO-MDSC: monocytic myeloid-derived suppressor cells, MFI: mean fluorescence intensity