Expression of programmed death ligand-1 on bladder tissues is detected in a clinically and histologically well-defined interstitial cystitis cohort

To investigate the expression of programmed death ligand-1 (PD-L1) in interstitial cystitis (IC). We reviewed the data of IC patients underwent hydrodistension plus bladder biopsy. Follow-ups were performed. We assessed the degree of inflammation of the bladder wall on slides stained with hematoxylin and eosin (H&E). We performed immunohistochemistry for PD-L1 expression detection and for counting T lymphocytes and B lymphocytes. The present study included eight men and 32 women. With H&E staining, we detected 13, 15, and 12 patients with mild, moderate, and severe inflammation. The degree of inflammation was negatively correlated with disease course (P = 0.018) and positively correlated with bladder pain (P