| Objective: To determine the expression levels of TAM/Gas6 pathway proteins Tyro3,Axl,Mer TK,and Gas6 in muscle tissues of dermatomyositis(DM)patients,and to investigate their role and significance in the pathogenesis of DM.Methods: Twenty patients with DM admitted into the Qinghai university affiliated hospital from November 2019 to July 2021 were enrolled as DM group,and 20 cases of simple orthopedic trauma surgery in our hospital at the same time were selected as control group.Pathological changes in muscle tissues were observed in two groups by hematoxylin & eosin(HE)staining,and the expression levels of Tyro3,Axl,Mer TK,and Gas6 in muscle tissues of two groups were detected by immunohistochemistry.Results: 1.HE staining showed that the skeletal muscle tissues of DM group showed different degrees of muscle fibers deformation,necrosis and atrophy,and obvious inflammatory cell infiltration,the pathological score of HE staining of skeletal muscle tissues in DM group was 2.06±0.63 points.The morphology and structure of skeletal muscle fibers in control group were basically normal,and no deformation,necrosis and atrophy of muscle fibers were observed,the pathological score of HE staining of skeletal muscle tissues in control group was 0.45±0.33 points.The pathological score of HE staining in DM group was significantly higher than that in control group(P<0.05).2.The expression levels of Tyro3,Axl,Mer TK,and Gas6 in muscle tissues of DM group were significantly decreased than those in control group(P<0.05).3.The immunohistochemical score of Gas6 in muscle tissues of DM group was positively correlated with the those of Tyro3,Axl,and Mer TK(P<0.05).4.In DM group,the pathological score of HE staining was negatively correlated with the immunohistochemical scores of Tyro3,Axl,Mer TK and Gas6(P<0.05).5.The immunohistochemical score of Tyro3,Axl,Mer TK and Gas6 were negatively correlated with C-reactive protein level in DM group(P<0.05).6.The immunohistochemical score of Tyro3 was negatively correlated with skin disease activity,muscle disease activity,lung disease activity and global disease activity in DM group(P<0.05).The immunohistochemical score of Axl was negatively correlated with skin disease activity,muscle disease activity,lung disease activity and global disease activity in DM group(P<0.05).The immunohistochemical score of Mer TK was negatively correlated with skin disease activity,muscle disease activity,lung disease activity and global disease activity in DM group(P<0.05).The immunohistochemical score of Gas6 was negatively correlated with skin disease activity,muscle disease activity,lung disease activity,and global disease activity in DM group(P<0.05).Conclusion: TAM/Gas6 pathway proteins Tyro3,Axl,Mer TK and Gas6 may be involved in the pathogenesis of DM by inhibiting the inflammatory response of DM patients and thus alleviating the inflammatory injury of muscle tissues.Tyro3,Axl,Mer TK and Gas6 may be helpful to evaluate the degree muscle tissues injury in DM. |
