CD274 and prostatitis: Investigating prostatic inflammatory histopathology for years, we conducted a study to quantitatively and qualitatively assess the PD-L1 (1:200, clone QR1, BIOCYC, Potsdam, Deutschland) immunohistochemical expression in 152 cases of various forms of CI of the prostate: National Institutes of Health, category IV prostatitis or histologic prostatitis (HP), various types of granulomatous prostatitis (GP), and the reactive lymphoid infiltrates near of BPH and PCa [8,9].