MAB941 Sigma-AldrichAnti-Coxsackievirus B4 Antibody, clone 371-3D-7H-6G

OBJECTIVE: Primary Sjögren's syndrome (SS) is an autoimmune disease characterized by activation of minor salivary gland (MSG) epithelial cells and B and T lymphocytic infiltrates. These findings have long encouraged the hypothesis that a persistent viral infection of the MSG epithelial cells may drive the autoimmune response; however, the identity of that virus has remained elusive. The aim of this study was to test this hypothesis. METHODS: We applied the differential display protocol to MSG RNA samples from patients with primary SS and healthy controls. We then used seminested reverse transcriptase-polymerase chain reaction to amplify the 5'-noncoding region (5'-NCR) of the enteroviral genome in 8 patients with primary SS, 9 patients with secondary SS, and 8 control subjects. Immunohistochemistry was performed to study the expression of the VP1 enteroviral capsid protein in MSG biopsy samples from 12 patients with primary SS, 8 patients with secondary SS, and 16 controls. RESULTS: Differential display analysis yielded a 94-bp fragment of coxsackievirus B4 (CVB4) P2A gene in the primary SS samples. The 5'-NCR was amplified in 7 samples from patients with primary SS and in no samples from patients with secondary SS or controls. The 7 amplified products were sequenced; 4 of the sequences were found to be 98-99% identical to the 5'- NCR of CVB4, and 3 were found to be 97-98% identical to the 5'-NCR of CVA13. Immunohistochemistry for the enteroviral capsid protein VP1 revealed positive staining in epithelial cells and lymphocytic infiltrates in 11 primary SS samples, 1 secondary SS sample, and no control samples. CONCLUSION: We provide evidence that primary SS may be associated with coxsackievirus infection of the MSG epithelial cells and focal lymphocytic infiltrates. Our findings are formulated in a hypothesis concerning the possible role of coxsackieviruses in the induction and maintenance of autoimmunity in primary SS.

A persistent infection of rhabdomyosarcoma (RD) cells by Coxsackie B4 virus (CBV-4) was established. The persistently infected RD (piRD) cells have been maintained for over 130 passages (30 months) and have released virus continuously without cellular destruction. The production of infectious virus declined three times during the study. After the first decline (third week post infection) a viral variant with a littered cytopathic effect (CPE) and a marked delayed replication cycle on Green Monkey Kidney (GMK) cells, replaced the original viral population. 100-fold diluted cell cultures were recovered from the piRD cells at the 48(th) and 104(th) passage. All 96 cultures from the former whereas 72% from the second dilution showed virus production when tested on GMK cells. Using a streptavidin/biotin immune-staining assay all piRD cells were positively stained. Test for ts mutants showed that the persistence of the CBV-4 strain was not dependent upon incubation temperature and addition of the antiviral compound disoxaril did not cure the piRD cells.