RT Journal Article SR Electronic T1 Expression of type III collagen mRNA in renal biopsy specimens of patients with idiopathic membranous glomerulonephritis JF Clinical Molecular Pathology JO Clin Mol Pathol FD BMJ Publishing Group Ltd and Association of Clinical Pathologists SP M40 OP M42 DO 10.1136/mp.49.1.M40 VO 49 IS 1 A1 M S Razzaque A1 T Taguchi YR 1996 UL http://mp.bmj.com/content/49/1/M40.abstract AB Aim—To investigate the distribution of type III collagen in membranous glomerulonephritis (MGN); to identify the cells responsible for the synthesis of α1 (III) mRNA. method—The distribution of type III collagen was studied by immunohistochemistry in 10 renal biopsy specimens, histologically diagnosed as MGN, and five control renal tissue samples obtained at surgery. Synthesis of α1 (III) mRNA was detected by non-radioactive in situ hybridisation. Results—On immunohistochemistry, type III collagen was not observed in the control glomeruli, but was present focally in the glomeruli in samples from patients with MGN. No specific hybridisation signal for α1 (III) mRNA was found in the control glomeruli on non-radioactive in situ hybridisation. By contrast, positive signals for α1 (III) chain mRNA were detected in glomerular epithelial cells and mesangial cells in MGN tissue samples. Conclusion—These data suggest that additional synthesis of type III collagen by intraglomerular cells contributes to the changes in the glomerular basement membrane characteristic of MGN.