Fibroblast is the main cellular component of loose connective tissue and is differentiated from Mesenchymal cell in embryonic period. Fibroblast large, clear outline, mostly raised spindle or star flat structure, the nucleus was a regular oval, large and obvious nucleoli. According to different functional activities, cells can be divided into Fibroblast and fibroblasts, Fibroblast function activity, cytoplasm weak alkaline, with significant protein synthesis and secretion activity, under certain conditions, it can be achieved with the conversion of fibroblasts . Fibroblast plays a very important role in various degrees of cellular degeneration, necrosis and tissue defects as well as the repair of bone trauma.
Principle of action
Fibroblast uptake of the required amino acids, such as proline and lysine in the rough endoplasmic reticulum synthesis of prokaryotic protein chain, polypeptide chain delivery to the Golgi complex, the composition of Procollagen. Procollagen is delivered by the secretory vesicles to the cell surface and then released outside the cell by exocytosis. With procollagenase catalysis, the tail of each pre-alpha polypeptide chain is removed and becomes Tropocollagen. Many Tropocollagen are arranged in parallel to form collagen fibrils with periodic stripes. Collagen fibrils are combined with each other to form collagen fibers.
General trauma repair
A variety of trauma will cause varying degrees of cell degeneration, necrosis and tissue defects, must be through cell proliferation and the formation of intercellular matrix for tissue repair. Fibroblast plays a very important role in this repair process. Taking wound healing process as an example, Fibroblast proliferates largely through mitosis and synthesizes and secretes large amounts of collagen fibers and matrix components from 4 to 5 days or 6 days to form granulation tissue together with nascent capillaries to fill wound tissue defects, The coverage of epidermal cells creates conditions. In wound healing, Fibroblast mainly comes from the dermal papillary layer of local Fibroblast and undifferentiated mesenchymal cells, and perivascular Fibroblast and pericytes. Fibroblast involved in the repair process mostly comes from the interstitium and envelope, as well as submucosal or sub-serous connective tissue when visceral lesions are involved. It is thought that a large number of Fibroblast accumulated in wounds during wound healing are derived from Fibroblast by dividing and proliferating on the one hand, and more from adjacent mesenchymal cells, fibroblasts and pericytes, etc. Injury. In the later stages of wound healing, Fibroblast is involved in the remodeling of tissue after repair by secreting collagenase. Under certain pathological conditions, granulation tissue or hyperplastic tissue mass with Fibroblast as the main cell component can also calcify in non-bone tissue, causing Ectopic ossification. However, it is unclear how Ectopic ossification participates in the cells and their mechanisms. The undifferentiated mesenchymal cells, Fibroblast, endothelial cells and pericytes can be classified as induced osteoprogenitors cells are likely involved in this process.