Loss of organized fibronectin matrix from the surface of aging diploid fibroblasts (IMR-90).
Indirect immunofluorescence was used to investigate the production of a fibrillar fibronectin matrix by human diploid fibroblasts (IMR-90) as cells progress through their in vitro lifespan. Early and mid-passage cultures displayed a prominent fibrillar reticulum over the cell layer which formed within 24 hours of seeding. Even sparsely seeded early-passage cells exhibited fibrils of fibronectin on external surfaces. In contrast, fibrillar fibronectin was reduced or absent on surfaces of late-passage cells. However, the larger, non-proliferating, late-passage cells were producing fibronectin, 1h determined by radioimmunoassay of the medium.
D000375:Aging; D002460:Cell Line; D002478:Cells, Cultured; D004171:Diploidy; D005347:Fibroblasts / Q000378:metabolism*; D005353:Fibronectins / Q000378:metabolism*; D005455:Fluorescent Antibody Technique; D006801:Humans; D011863:Radioimmunoassay; D013997:Time Factors
D005353:Fibronectins