Comparison Study between Immunohistochemical Staining and Enzyme Linked Immunosorbent Assay in Metalloproteinases and Tissue inhibitor of Metalloproteinases in Virus induced Myocarditis

ABSTRACT

PURPOSE: Most tissue disruption of extracellular matrix is mediated by extracellular proteinases. Matrix metalloproteinases(MMP) and tissue inhibitor of matrix metalloproteinases(TIMP) are associated with wound healing and repair. There has been no study done on MMP and TIMP in myocarditis. METHODS: Coxsackie B virus(4,000 plaque forming unit) was injected into Balb/c mice by intraperitoneal injection. Histopathological finding was observed by H-E staining. Immunohistochemical staining was performed using the Labelled Streptavidin Biotin(LSAB) kit for MMP-2, TIMP-2, and Interleukin(IL) 6. The results were compared to the serum levels by ELISA method. RESULTS: MMP-2 was strongly expressed in complicated myocarditis such as calcification, severe fibrosis, thrombosis, or dilated cardiomyopathy compared to normal or uncomplicated myocarditis. TIMP-2 expression was decreased in severe myocarditis. Serum MMP-2 levels were significantly higher in complicated myocarditis, but TIMP-2 levels were significantly lower. There was significant correlation between the grade of immunohistochemical staining and serum MMP-2 or TIMP-2 level by ELISA method. IL-6 was strongly expressed in immunohistochemical staining according to the severity of inflammation. CONCLUSION: There was significant correlation between grade of immunohistochemical staining and serum levels of MMP or TIMP by ELISA method. Accurate estimations of serum MMP and TIMP levels would be useful for the diagnosis and follow up of myocarditis.