瘢痕表皮角蛋白的变化规律及正常表皮细胞培养液对成纤维细胞胶原合成的影响

目的：研究增生性瘢痕和正常皮肤表皮角蛋白的变化规律以及正常表皮细胞培养液对瘢痕和正常皮肤成纤维细胞增殖和胶原合成的影响。方法：4例烧伤患者，每人取少量增生性瘢痕和临近的正常皮肤组织，用免疫组化法观察两种组织中与细胞增殖有关的角蛋白14、与细胞分化有关的角蛋白10和与细胞活化有关角蛋白16的变化。收集正常表皮细胞培养12h后的无血清培养液，用DMEM依次配成体积分数为0、5％、10％和20％，分别加入到加有正常和瘢痕组织成纤维细胞的培养板中。分别以MTT法测定吸光度（A）值，Beckman液闪计数仪测定3H-脯氨酸掺人值，分别用以反映成纤维细胞的增殖和胶原合成速率。结果：与正常表皮比较，瘢痕表皮中角蛋白16明显表达增强，角蛋白10降低，角蛋白14无明显变化；正常表皮细胞培养液能促进正常皮肤和瘢痕成纤维细胞的增殖并抑制胶原的合成，但对两种成纤维细胞的作用程度不尽相同，对正常成纤维细胞增殖的促进作用和对胶原合成的抑制作用都较瘢痕成纤维细胞显著。结论：瘢痕表皮的活化可能是瘢痕增生的一个重要因素；正常表皮细胞培养液既能促进成纤维细胞增殖，还能抑制胶原的合成，但对瘢痕成纤维细胞胶原合成的抑制作用较正常成纤维细胞弱。

The changes in keratins in epidermis and effects of medium for keratinocyte culture on synthesis of collagen in fibroblasts

Objective：To observe the changes in keratins in scar or normal epidermis, and effects of the medium for normal keratinocyte culture on synthesis of collagen in scar or normal fibroblasts. Methods： Biopsy specimens were obtained from hypertrophic scar and adjacent unburned skin. The tissues were analyzed using histoimmunochemical staining for markers of keratinocyte proliferation, differentiation and activation （keratin 14, 10 and 16 respectively）. Medium for normal keratinocyte culture in different concentrations （0%, 5%, 10%, 20%） were collected to incubate normal and scar fibroblasts for 12 hours. Cell replication was quantified by MTT method. Collagen synthesis was quantified by the incorporation of 3 H-proline into collagen-sensitive protein. Results.- A significantly higher expression of keratin 16 and weaker expression of keratin 10 were observed without significant change in keratin 14 in the epidermis of scars compared with normal control skin. Keratinocyte conditioned medi- um induced a significant increase in replication and a decrease in collagen synthesis in normal skin-derived fibroblasts than fibroblasts obtained from scar. Conclusions：Activation of keratinocytes plays an important role in the formation of scar. keratinocyte conditioned medium could promote replication of fibroblasts but alleviate the collagen synthesis by fibroblasts.