ROLE OF BLOOD PLATELETS IN SKIN WOUND HEALING

这项研究的目的是为了更清楚地理解这种动态 表皮再生和真皮修复的过程，特别是在 治愈。在正常情况下，皮肤会不断地自我维持和恢复 组织周转。受伤后的修复过程尤其是 明显的，并可包括在休息条件下不存在的活动， 以及体内平衡活动的增加。治愈发生在 对任何组织扰动的反应表明许多慢性病 部分是不完全或不正常愈合的问题。血小板源 因子(PDF)对培养中的结缔组织细胞有显著影响 并可能在皮肤的愈合反应中发挥重要作用。PDF有 已经描述了真皮成纤维细胞和其他 结缔组织细胞，但尚未发现影响表皮的细胞 细胞。研究人员已经确定了一种血小板匀浆分数(PHF) 在外植体培养中支持和刺激表皮细胞。 (外植体培养是由表皮制成的中厚皮肤切片 和最浅的乳头状真皮。)PHF已被分离为 两个活性部位，每一个对表皮细胞有不同的影响。 这两个部分与目前已知的PDF截然不同。具体的 该方案的目的是1)完成分离和表征 PHF中影响表皮细胞的因素，2)了解这些因素是否 因子直接作用于表皮或通过皮肤间接作用于皮肤。 要素，3)以了解表皮细胞事件(迁移、有丝分裂 和成熟)受PHF因素的影响，4)研究 这些因素对割伤后愈合过程的影响，5)研究它们的作用 对烧伤创面愈合的影响，表现出原因不明的延迟 治愈，可能是因为没有PDF。PHF将被分馏和 以已成功应用的标准技术为特征的 到其他PDF，包括层析、亚细胞分离、凝胶 酶法、化学法和物理法的电泳法和灭活法 条件。生成的组分将在体外用PIG和 人皮肤准备外植体和原代表皮细胞培养 (不包括皮肤影响)。伤口愈合将在#年研究 建立实验猪模型。这项研究将提供新的 关于来自血小板的生理因子的信息及其如何 参与皮肤生物学和修复过程。

The research is directed toward a clearer understanding of the dynamic processes of epidermal regeneration and dermal repair, especially during healing. The skin continually maintains and restores itself during normal tissue turnover. After injury the process of restoration is particularly pronounced and may include activities not present under resting conditions, as well as an increase in homeostatic activities. Healing occurs in response to any tissue perturbation suggesting that many chronic diseases are partially a problem of incomplete or abnormal healing. Platelet-derived factors (PDFs) have dramatic effects on connective tissue cells in culture and may play an important role in the skin's healing response. PDFs have been described that are specific for dermal fibroblasts and other connective tissue cells, but none have been found which affect epidermal cells. The investigator has identified a platelet homogenate fraction (PHF) that both supports and stimulates epidermal cells in explant culture. (Explant cultures are split-thickness sections of skin made of epidermis and the most superficial papillary dermis.) PHF has been separated into two active fractions and each has a different effect on epidermal cells. The two fractions are distinct from PDFs that are now known. The specific aims of this proposal are 1) to complete the isolation and characterization of the factors in PHF affecting epidermal cells, 2) to learn whether these factors act directly on the epidermis or indirectly through dermal elements, 3) to learns how epidermal cellular events (migration, mitosis and maturation) are influenced by PHF factors, 4) to study the effects of these factors on the healing process after a cut wound, 5) to study their effects on healing after a burn wound, which shows an unexplained delay in healing, perhaps due to the absence of PDFs. PHF will be fractionated and characterized using standard techniques that have been successfully applied to other PDFs, including chromatography, subcellular fractionation, gel electrophoresis and inactivation by enzymatic, chemical and physical conditions. The resultant fractions will be studied in vitro using pig and human skin to prepare both explants and primary epidermal cell cultures (which exclude dermal influences). Wound healing will be studied in established experimental porcine models. This research will provide new information about physiological factors from platelets and how they are involved in cutaneous biology and repair processes.