Anti-CypA single-domain antibody A1 suppresses matrix metalloproteinase-9 and human inflammatory cytokine production in SCID-HuRAg mice. (A) Representative images of matrix metalloproteinase (MMP)-9 staining of each treatment group under a microscope (n = 6 per group) (magnification × 400). (B) Statistical results for the expression of MMP-9 in each treatment group. (C) The blood of sacrificed mice was obtained and the levels of cytokines were detected by cytometric bead array (CBA). Results are expressed as the mean ± standard error of the mean with n = 6 per group. *P <0.05 compared with the control antibody group, **P <0.01 versus control antibody group. IHC, immunohistochemistry; IL, interleukin; PBS, phosphate-buffered saline; sdAb, single-domain antibody; TNF, tumor necrosis factor.