Myofibroblasts, differentiation fibroblasts

Olson, E.R., Naugle, J.E., Zhang, X., Bomser, J.A., and Meszaros, J.G. 2005. Inhibition of cardiac fibroblast proliferation and myofibroblast differentiation by resveratrol. Am. J. Physiol. 288 H1131-H1138. 

Masur, S.K., Dewal, H.S., Dinh, T.T., Erenburg, I., and Petridou, S. 1996. Myofibroblasts differentiate from fibroblasts when plated at low density. Proc. Natl. Acad. Sci. USA 93 4219 1223. 

During the healing process, hybrid cells, known as myofibroblasts, appear in the dermis. They have the morphological characteristics of both fibroblasts and smooth muscle cells. They are responsible for tissue contraction-retraction during healing. Their cytoplasm contains networks of myofilaments that are in contact with specialized zones of the plasma membrane and can interact with the adjacent cells or connective tissue. These myofibroblasts appear to be differentiated fibroblasts that have acquired the properties of smooth muscle cells. Controlled stimulation with DMAE, for example, is a good way to achieve a tightening effect on the skin. 

In general, tumors showing pure fibroblastic or myofibroblastic differentiation are uncommon. Only three cutaneous neoplastic proliferations fall into that... 

Tseng SC, Li DQ, Ma X. Suppression of transforming growth factor-beta isoforms, TGF-beta receptor type II, and myofibroblast differentiation in cultured human corneal and hmbal fibroblasts by amniotic membrane matrix. J Cell Physiol 1999 179 325-35. 

Nonactivating In addition to white blood cell interactions, new PUs should prevent fibroblast to myofibroblast differentiation to [57]... 

Fig. 14.1. The Thl/Th2 balance is central to the regulation of normal wound repair. Tissue injury results in the initiation of an inflammatory response, mediated by a variety of cells and their by-products. Immune cells are recruited and cross-regulate the Thl/ Th2 balance that occurs in response to the cytokine environment. This balance is in turn cross-regulated by the chemokine/chemokine-receptor expression profile, which functions to amplify the inflammatory process. Cells residing in the injured tissue release profibrotic mediators, which promote fibroblast activation, proliferation, and differentiation to the myofibroblast phenotype. Myofibroblasts produce collagen to repair damaged tissue, which is an event that is favored by the inhibition of MMP activity. The Thl/Th2 balance is central to whether a normal or aberrant wound-repair process is established A Thl environment promotes normal tissue resolution (fibrinolysis), whereas a Th2 environment maintains the progression of fibrotic disease (excessive collagen deposition).

Evans, R.A., Tian, Y.C., Steadman, R., and Phillips, A.O. 2003. TGF-betal-mediated fibroblast-myofibroblast terminal differentiation—the role of smad proteins. Exp. Cell Res. 282 90-100. 

Patterns of mesenchymal differentiation in cutaneous neoplasms are no less diverse than those encountered in deeper soft tissues. Fibroblastic or myofibroblastic, fibrohistiocytic, muscular, neural, epithelial, and vascular lesions may be seen as primary tumors in the dermis and subcutis. As is also true in deep soft tissues, the histologic evaluation of those neoplasms may fail to provide an unequivocal diagnosis. Hence immunophenotyping has proven to be valuable in this context. The diagnostic separation of various spindle-cell, polygonal-cell, epithelioid-cell, and small-cell lesions of the skin is assisted in many settings by immunohistochemical analysis. 

Depending on the retinoic acid concentration, a continous cellular spectrum ranging from fibroblast/myofibroblast to SMC can be obtained from P19 embryonal cells grown in vitro [371]. Since fibroblasts are considered a heterogeneous cell population, possibly with a dual differentiative capacity, it is likely that appropriate availability of specific regulating factors... 

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