title: Ultrastructural immunocytochemical localization of type I procollagen in cultured human fibroblasts.
abstract: An immunoelectron microscopic study of cultured human fibroblasts was performed with antibody specific for the carboxyl propeptides of human type I procollagen (Goldberg et al., 1985). In cells permeabilized with detergent, the unlabeled antibody peroxidase-antiperoxidase method localized the antigen in the rough endoplasmic reticulum, in the Golgi complex, and upon the plasma membrane. Immunostained thread-like periodic fibrillar aggregates within cytoplasmic vacuoles were not apparent. Extracellular fibrils 20-80 nm in thickness were diffusely and heavily stained. Immunostaining also defined a thin extracellular periodic fibril (diameter 10-20 nm; axial period 53.7 nm +/- 6.5 S.D.). These data are discussed in terms of current views of procollagen secretion and collagen fibrillogenesis.
mesh_terms: D002460:Cell Line; D005347:Fibroblasts / Q000648:ultrastructure; D007106:Immune Sera; D007118:Immunoassay; D008854:Microscopy, Electron / Q000379:methods; D011347:Procollagen / Q000032:analysis*; D012867:Skin / Q000648:ultrastructure*
chemical_list: D007106:Immune Sera; D011347:Procollagen