Which of the following cell types are not crucial for healing a clean, incisional wound? A.  Macrophage. B.  Platelet. C.  Fibroblast. D.  Polymorphonuclear leukocyte. E.  Myofibroblast.

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Answer :

Answer: DE  DISCUSSION: Experimental studies have shown that healing may progress normally in the absence of polymorphonuclear leukocytes in an uninfected wound. In contrast, depletion of monocytes and macrophages causes a severe alteration in wound healing with poor débridement, delayed fibroblast proliferation, and inadequate angiogenesis. Platelets carry a cadre of biologically active substances that are important for wound repair, including peptide growth factors like platelet-derived growth factor (PDGF) and TGF-b. Fibroblasts are the principal cell for matrix synthesis and deposition. Myofibroblasts are important for wound contraction in open defects but have little if any role in clean, incisional wounds

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