Editing Fibronectin (section)

== Role in wound healing ==
Fibronectin has profound effects on [[wound healing]], including the formation of proper substratum for migration and growth of cells during the development and organization of [[granulation tissue]], as well as remodeling and resynthesis of the connective tissue matrix.<ref name="pmid 7240787 ">{{cite journal | vauthors = Grinnell F, Billingham RE, Burgess L | title = Distribution of fibronectin during wound healing in vivo | journal = The Journal of Investigative Dermatology | volume = 76 | issue = 3 | pages = 181–189  | date = Mar 1981 | pmid = 7240787 | doi = 10.1111/1523-1747.ep12525694 | doi-access = free }}</ref> The biological significance of fibronectin ''in vivo'' was studied during the mechanism of wound healing.<ref name="pmid 7240787 " />  Plasma fibronectin levels are decreased in acute inflammation or following surgical trauma and in patients with [[disseminated intravascular coagulation]].<ref name="pmid1002003">{{cite journal | vauthors = Bruhn HD, Heimburger N | title = Factor-VIII-related antigen and cold-insoluble globulin in leukemias and carcinomas | journal = Haemostasis | volume = 5 | issue = 3 | pages = 189–192 | year = 1976 | pmid = 1002003 | doi = 10.1159/000214134 }}</ref>

Fibronectin is located in the extracellular matrix of embryonic and adult tissues (not in the [[basement membrane]]s of the adult tissues), but may be more widely distributed in inflammatory lesions.  During blood clotting, the fibronectin remains associated with the clot, covalently cross-linked to [[fibrin]] with the help of [[Factor XIII]] (fibrin-stabilizing factor).<ref name="pmid1158872">{{cite journal | vauthors = Mosher DF | title = Cross-linking of cold-insoluble globulin by fibrin-stabilizing factor | journal = The Journal of Biological Chemistry | volume = 250 | issue = 16 | pages = 6614–6621 | date = Aug 1975 | doi = 10.1016/S0021-9258(19)41110-1 | pmid = 1158872 | doi-access = free }}</ref><ref name="pmid56335">{{cite journal | vauthors = Mosher DF | title = Action of fibrin-stabilizing factor on cold-insoluble globulin and alpha2-macroglobulin in clotting plasma | journal = The Journal of Biological Chemistry | volume = 251 | issue = 6 | pages = 1639–1645 | date = Mar 1976 | doi = 10.1016/S0021-9258(17)33696-7 | pmid = 56335 | doi-access = free }}</ref> [[Fibroblast]]s play a major role in wound healing by adhering to fibrin. Fibroblast adhesion to fibrin requires fibronectin, and was strongest when the fibronectin was cross-linked to the fibrin. Patients with Factor XIII deficiencies display impairment in wound healing as fibroblasts don't grow well in fibrin lacking Factor XIII. Fibronectin promotes particle [[phagocytosis]] by both [[macrophage]]s and fibroblasts. Collagen deposition at the wound site by fibroblasts takes place with the help of fibronectin. Fibronectin was also observed to be closely associated with the newly deposited [[collagen]] fibrils. Based on the size and [[Histology|histological]] staining characteristics of the fibrils, it is likely that at least in part they are composed of type III collagen ([[reticulin]]). An ''in vitro'' study with native collagen demonstrated that fibronectin binds to type III collagen rather than other types.<ref name="pmid 567240 ">{{cite journal | vauthors = Engvall E, Ruoslahti E, Miller EJ | title = Affinity of fibronectin to collagens of different genetic types and to fibrinogen | journal = The Journal of Experimental Medicine | volume = 147 | issue = 6 | pages = 1584–1595 | date = Jun 1978 | pmid = 567240 | pmc = 2184308 | doi = 10.1084/jem.147.6.1584 }}</ref>