ROLE OF BLOOD PLATELETS IN SKIN WOUND HEALING

这项研究旨在更清楚地了解 表皮再生和真皮修复的过程，特别是在 治愈 皮肤在正常情况下会不断地自我维持和恢复。 组织周转 受伤后的恢复过程尤其重要。 明显的并且可以包括在静止条件下不存在的活动， 以及体内平衡活动的增加。愈合发生在 对任何组织扰动的反应表明许多慢性疾病 部分是不完全或异常愈合的问题。血小板衍生 PDFs对培养的结缔组织细胞有显著的影响 并可能在皮肤的愈合反应中发挥重要作用。 PDF有 已经描述了对真皮成纤维细胞和其他 结缔组织细胞，但没有发现影响表皮 细胞研究者已确定血小板匀浆部分（PHF） 既支持又刺激外植体培养中的表皮细胞。 （外植体培养物是由表皮制成的皮肤的分层切片， 和最浅的乳头状真皮。） PHF已被分为 两种活性组分，每种对表皮细胞具有不同的作用。 这两个分数与现在已知的PDF不同。具体 该提案的目的是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真皮间接作用于表皮， 元素，3）学习如何表皮细胞事件（迁移，有丝分裂 和成熟）受PHF因素的影响，4）研究PHF因素对 这些因素对伤口愈合过程的影响，5）研究它们对伤口愈合的影响。 对烧伤后伤口愈合的影响，这表明了一个无法解释的延迟， 治疗，也许是由于没有PDF。将对PHF进行分级， 使用已成功应用的标准技术表征 其他PDF，包括色谱，亚细胞分级，凝胶 电泳和酶、化学和物理灭活 条件 将在体外使用猪和 人皮肤以制备外植体和原代表皮细胞培养物 （不包括皮肤影响）。 伤口愈合将在 建立了实验猪模型。这项研究将提供新的 关于血小板的生理因子的信息以及它们如何 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.