Wound response phenotype

The roles of ABA in seed development and in response to drought, salt and cold stress are the most extensively studied effects of the hormone. However, ABA is also involved in other processes. ABA deficient mutants of potato and tomato show reduced response to wounding. Application of ABA can reverse the phenotype demonstrating the direct relationship between ABA and wound response [34]. Treatment of bromegrass cell cultures with ABA induces increased heat tolerance. At least four days of ABA treatment is needed to achieve tolerance. This effect of ABA is thus a slow response like the cold acclimation and induction of desiccation tolerance in C. plantagineum. 

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).

An ideal scaffold should possess excellent biocompatibility, controllable biodegradability and suitable mechanical characteristics. Several studies have shown that nanofibrous scaffolds can enhance cellular responses like cell adhesion and cell phenotype maintenance. Electrospun PCL nanofibrous scaffolds can be fabricated in the laboratory for the treatment of partial or full thickness skin defects. These nanofibrous wound dressings, due to their porosity and inherent properties might... 

Ml and M2 are known to be directly related to proinflammatory and homeostatic/ wound healing respectively and are present both in innate and adaptive immune responses (Franz et al 2011 Scislowska-Czamecka et al., 2012 Galdiero and Mantovani, 2015). M2 is known to be clearly discerned from the well-characterized Ml cell type, yet it probably represents an even broader group of macrophages with activity spectra completely different from the Ml phenotype. 

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