人创面愈合过程中同源异形框基因的表达及意义

目的 探讨人胎儿及成人皮肤创面愈合过程中，几种同源异形框基因的表达及在胎儿无瘢痕愈合中的作用。方法 采用原位杂交方法，对正常成人和胎儿皮肤及创面愈合过程中PRX—2、H0XBl3、H0X2．2和H0X2．3的表达进行观察。结果 (1)在正常胎儿和成人皮肤中可见PRX—2阳性表达，以前阳性程度为强。分布部位有所不同，在正常胎儿皮肤中，阳性表达主要见于真皮乳头层毛干部周围细胞，表皮中也可见阳性表达；而在正常成人皮肤中，表皮基底层细胞呈弱阳性表达，真皮组织中未见阳性表达。胎儿皮肤创伤后，接近切口的组织中阳性表达明显增强，而成人皮肤创伤后，阳性表达未见明显变化，仍局限于表皮基底层细胞；(2)在正常胎儿及成人皮肤均可见H0XBl3阳性表达，真皮部分主要集中在毛囊细胞，表皮部分主要集中在基底层细胞，创伤后其表达明显减弱，尤其是胎儿皮肤；(3)在正常胎儿皮肤中H0X2．2和H0X2．3阳性表达主要见于表皮全层，表皮基底层阳性表达比较强，真皮中可见弱阳性表达，创伤后近切口的组织中，表达增强。在正常成人皮肤及其创面，未见到阳性表达。结论 同源异形框基因作为与发育生物学密切相关的基因，在人胎儿及成人皮肤创面愈合过程中的表达有所不同，这可能是二创面愈合差异的根本原因。

The significance and the expression of homeobox genes during human burn wound healing

Objective To investigate the expression of several homeobox genes during the wound healing in fetal and adult skin and their roles in fetal scarless wound healing. Methods The expressions of PRX 2, HOXB13, HOX2.2 and HOX2.3 during wound healing in fetal and adult skin were determined with in situ hybridization. Results (1) PRX 2 positive expression could be identified in normal fetal and adult skin, especially in the fetus. But there was difference in location sites of the genes. The positive expression in normal fetal skin was mainly found in the peripheral cells at the hair shafts within dermal papilla layers and was also found in the epithelium. Nevertheless, weak positive expression of PRX 2 was found in the epithelial basal layer cells in normal adult skin but not in dermal tissue. There was strong positive expression of the PRX 2 in the tissue around the wound in fetus but not of that in adults except the epithelial basal layers. (2) Positive expression of HOXB13 could be identified in both normal fetal and adult skins. And the expression was concentrated mainly in hair follicle cells in the dermis and in the basal layer cells in the epithelium. Furthermore, the expression became weak after trauma, especially in fetal skin. (3) The positive expression of HOX2.2 and HOX2.3 in normal fetal skin was observed mainly in the whole layer of the epithelium and especially in the epithelial basal layers. Weak positive expression could be found in the dermis and strong expression found in the tissue near the wound. But there was no positive expression of the HOX genes in normal adult skin and wounds. Conclusion The difference in the HOX expression in fetal and adult skin wound healing might be the key factor leading to different wound healing. Homeobox genes might be closely related with the developmental biology.