Wound Healing and Collagen Formation

Abstract

The sequence encountered in healing skin wounds in scorbutic guinea pigs has been examined by mcthods of light and electron microscopy. Linear incisions in the skin of female guinea pigs fed a scorbutigcnic diet were allowed to heal. The wounds were removed for examination at l, 3, 5, 9, and 14 days after wounding. The fibroblasts of the scorbutic wounds diffcr from those of the controls in thrcc major aspects. First, little collagen is present within the intcrcellular spaces, although small groups of individual collagen fibrils can be found adjacent to some of the fibroblasts; in addition, large amounts of somewhat fibrillar, poorly structured, dense matter arc present throughout the cxtracellular regions. The second alteration consists of large aggregatcs of intracytoplasmic lipid deposits present within the majority of the fibroblasts. Third, the cndoplasmic reticulum of the fibroblasts is altcrcd in form from that of the controls. The profiles of thc cistcrnae arc round, non-continuous within the plane of section, and are less cxtcnsivcly devclopcd than in the controls. An increased macrophagic activity of the histiocytes is also described. These changes are discussed in light of the available biochemical data associated with this abnormality of protein synthesis.

Neutrophil-Epithelial Interactions

“…In addition, it is well documented that infiltration of inflammatory cells, including neutrophils, macrophages, and lymphocytes, is necessary for the process of mucosal wound healing. 8,9 Typically, neutrophils begin arriving at wounded sites within minutes of injury and persist for several days before being cleared by macrophages. During this time, neutrophils are an important source of proinflammatory cytokines, including IL-1a, IL-1b, tumor necrosis factor a, 10 and others.…”

Wound Healing and Collagen Formation

“…The tissues were examined with an RCA-EMU 3E or 3G electron microscope. The description of fibroblasts from non-deficient animals represents a much larger number of observations from previous and present experiments (7)(8)(9)51).…”

“…With the animal under ether anesthesia (8), linear incisions, approximately 1 cm long, were made in the dorsal skin of a separate group of 12 female guinea pigs after these animals had been fed for 14 days on the scorbutigenic diet. A wound was removed, as previously described (7), prior to ascorbic acid administration.…”

“…The aim of the present studies is to further characterize the deviations seen in the scorbutic state from those observed in the normal state during the process of wound healing, and to answer, if possible, some of the remaining questions. The principal previous findings (7)(8)(9) established : 1. Several aberrations in the appearance of the fibroblasts in the scorbutic state.…”

“…Do the argyrophilic fibers and the collagen, found very soon after ascorbic acid administration, come from material newly elaborated by the fibroblasts, or are these formed from material pre-existing in the interstitial space? In our previous investigations (7)(8)(9), the observations of the light microscopist were extended, and certain aspects of the cellular alterations were presented. The aim of the present studies is to further characterize the deviations seen in the scorbutic state from those observed in the normal state during the process of wound healing, and to answer, if possible, some of the remaining questions.…”