The role of fibronectin and substrate size in attachment of rat bone marrow cells to an osteoinductive matrix.
Culturing bone marrow cells in the presence of osteoinductive demineralized bone matrix particles results in increased cell proliferation. We have previously reported that this response is substrate specific and is not observed when cells are cultured with glass beads or collagenous tail tendon particles. In the present investigation, we show that a bone matrix particle size of less than 70 micrometers or greater then 420 micrometers is not supportive of cell attachment, as observed by the scanning electron microscope and that subsequent cell proliferation, as measured by DNA content, does not occur. The attachment of the bone marrow cells to bone matrix particles is dependent upon fibronectin, a serum glycoprotein. When serum was absent in the culture medium, cell attachment was still observed. Fibronectin was detected by an enzyme linked immunoabsorbent assay in cultures grown in the absence of serum. Therefore, fibronectin may be synthesized by bone marrow cells. When bone marrow cells were cultured in the presence of anti-fibronectin antibodies, the number of cells attaching to the matrix particles was greatly decreased. When cell attachment was reduced, the rate of cell proliferation as measured by DNA synthesis was also reduced. This study demonstrated that substrate size and fibronectin are important for the interaction of bone marrow cells with an osteoinductive matrix.
D000818:Animals; D000906:Antibodies; D001853:Bone Marrow / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure; D001842:Bone and Bones / Q000502:physiology*; D002448:Cell Adhesion / Q000187:drug effects; D002478:Cells, Cultured; D004247:DNA / Q000032:analysis; D005353:Fibronectins / Q000276:immunology / Q000502:physiology*; D008297:Male; D008855:Microscopy, Electron, Scanning; D051381:Rats
D000906:Antibodies; D005353:Fibronectins; D004247:DNA