Fig. 4.

Deficiency of programmed death-1 (PD-1) deficiency enhances M1 polarization of cultured microglia. (a) Western immunoblot for inducible nitric oxide synthase (iNOS; M1 phenotype) and arginase 1 (Arg1) (M2 phenotype) in primary microglial cells isolated from wild-type (WT) and PD-1-knockout (KO) mice and stimulated with lipopolysaccharide (LPS) + interferon (IFN)-γ or interleukin (IL)-4 for 24 h. Densitometric analysis of (b) iNOS and (c) Arg1 normalized to β-actin. Quantitative reverse transcription polymerase chain reaction of proinflammatory cytokines (d) Il12, (e) Il1b, and (f) Tnfa; anti-inflammatory cytokines (g) Il4, (h) Il10, and (i) Tgfb. n = 3 mice in each group. *p < 0.05, **p < 0.01, ***p < 0.001. Con = control; ns = not significant