Background Chondrocalcin, c-terminal of type II procollagen peptide, plays a major part in ossification processes by acting as a nucleation core of matrix calcification. Chondrocalcin and its related growth factors can also influence tendon and ligament formation and appear to be a key molecular pathway involved in this pathological cascade.
Objectives The purposes of this study were to evaluate the association of chondrocalcin in the pathogenesis of inflammation and calcification in an animal model of ankylosing spondylitis.
Methods Peripheral arthritis was induced by transferring the HLA-B2704 gene into male Kunming mice and their inflamed hid paw joints sections were obtained. Chondrocalcin was detected using real time-PCR and anti-chondrocalcin antibody developed from proteins occurred from C-terminal amino acid sequence of type II collagen. Immunohistochemical staining and western blot assay were performed to identify the expression and localization of chondrocalcin in joint sections of the animal model.
Results On immunohistochemistry, chondrocalcin was detected in inflamed joint tissues of animal models and this was more densely distributed in spindle-shaped fibroblast-like cells and hypertrophic chondrocytes. Chondrocalcin production was increased in hind paw joints of animal model compared to empty vector-injected mice and its mRNA expressions were also increased peripheral blood mononuclear cells from animal model compare to empty vector-injected mice.
Conclusions This study showed that chondrocalcin can be detected in inflammed tissues of animal models of AS and that the levels of condrocalcin productions and its gene expressions are increased in animal models. These results can provide an evidence for the role of chondrocalcin in pathogenesis of AS.
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Disclosure of Interest None declared