Kane C J, Hebda P A, Mansbridge J N, Hanawalt P C
Department of Biological Sciences, Stanford University, California 94305.
J Cell Physiol. 1991 Jul;148(1):157-73. doi: 10.1002/jcp.1041480119.
The expression of transforming growth factor (TGF beta 1) protein in human and porcine skin has been analyzed by immunohistochemistry with two polyclonal antibodies (anti-CC and anti-LC) following cutaneous injury. The anti-LC antibody binds intracellular TGF beta 1 constitutively expressed in the nonproliferating, differentiated suprabasal keratinocytes in the epidermis of normal human skin, while the anti-CC antibody does not react with the form of TGF beta 1 present in normal skin as previously shown. TGF beta 1 may play a role in wound healing as suggested by its effect on multiple cell types in vitro and its acceleration of wound repair in animals. We have evaluated the natural expression and localization of TGF beta 1 protein in situ during initiation, progression, and resolution of the wound healing response in two models of cutaneous injury: the human suction blister and the dermatome excision of partial thickness procine skin. Anti-CC reactive TGF beta 1 in the epidermis is rapidly induced within 5 minutes following injury and progresses outward from the site of injury. The induction reflects a structural or conformational change in TGF beta 1 protein and can be blocked by the protease inhibitor leupeptin or by EDTA, suggesting a change in TGF beta 1 activity. One day post-injury anti-CC reactive TGF beta 1 is present in all epidermal keratinocytes adjacent to the wound including the basal cells. This corresponds temporally to the transient block of the basal keratinocyte mitotic burst following epithelial injury. Three to 4 days post-injury anti-CC reactive TGF beta 1 is localized around the suprabasal keratinocytes, in blood vessels, and in the papillary dermis in cellular infiltrates. The exclusion of TGF beta 1 from the rapidly proliferating basal cells and its extracellular association with suprabasal keratinocytes may represent physiological compartmentation of TGF beta 1 activity. Anti-CC staining is strong in the leading edge of the migrating epithelial sheet. The constitutive anti-LC reactivity with suprabasal keratinocytes seen in normal epidermis is neither relocalized nor abolished adjacent to the injury, but anti-LC staining is absent in the keratinocytes migrating within the wound. As the wound healing response resolves and the skin returns to normal, anti-CC reactive TGF beta 1 disappears while constitutive anti-LC reactive TGF beta 1 persists. Thus, changes in the structure or conformation of TGF beta 1, its localization, and perhaps its activity vary in a spatial and temporal manner following cutaneous injury and correlate with physiological changes during wound healing.
皮肤损伤后，利用两种多克隆抗体（抗CC和抗LC）通过免疫组织化学分析了人及猪皮肤中转化生长因子（TGFβ1）蛋白的表达情况。抗LC抗体可结合正常人类皮肤表皮中在非增殖性、分化的基底上层角质形成细胞中组成性表达的细胞内TGFβ1，而如先前所示，抗CC抗体不与正常皮肤中存在的TGFβ1形式发生反应。TGFβ1对多种细胞类型具有体外作用，并能加速动物伤口修复，提示其可能在伤口愈合中发挥作用。我们在两种皮肤损伤模型中评估了伤口愈合反应起始、进展和消退过程中TGFβ1蛋白的天然表达及定位：人吸引水疱模型和猪部分厚度皮肤的皮片切除模型。损伤后5分钟内，表皮中抗CC反应性TGFβ1迅速被诱导，并从损伤部位向外进展。这种诱导反映了TGFβ1蛋白的结构或构象变化，可被蛋白酶抑制剂亮抑酶肽或EDTA阻断，提示TGFβ1活性发生了变化。损伤后一天，抗CC反应性TGFβ1存在于伤口附近所有表皮角质形成细胞中，包括基底细胞。这在时间上与上皮损伤后基底角质形成细胞有丝分裂爆发的短暂阻断相对应。损伤后3至4天，抗CC反应性TGFβ存在于基底上层角质形成细胞周围、血管中以及细胞浸润的乳头真皮中。TGFβ1从快速增殖的基底细胞中排除，并在细胞外与基底上层角质形成细胞结合，这可能代表了TGFβ1活性的生理分隔。在迁移上皮片的前沿，抗CC染色很强。在正常表皮中可见的与基底上层角质形成细胞的组成性抗LC反应性，在损伤附近既未重新定位也未消失，但在伤口内迁移的角质形成细胞中没有抗LC染色。随着伤口愈合反应消退且皮肤恢复正常，抗CC反应性TGFβ1消失，而组成性抗LC反应性TGFβ1持续存在。因此，皮肤损伤后，TGFβ1的结构或构象、其定位以及可能的活性会在空间和时间上发生变化，并与伤口愈合过程中的生理变化相关。
