透明质酸及其受体在不同皮肤组织创面愈合过程中的表达及意义

目的　探讨透明质酸 (HA)及其受体分化抗原簇 4 4 (CD4 4 )在增生性瘢痕、正常成人和胎儿皮肤创面愈合过程中的表达及其在胎儿皮肤无瘢痕愈合中的作用。方法　利用已建立的无瘢痕愈合动物模型 ,采用放射免疫、免疫组化染色和流式细胞仪方法 ,对增生性瘢痕、正常成人和胎儿皮肤及其创面愈合过程中HA及其受体的含量进行检测。结果　正常胎儿皮肤组织HA的含量 14 3μg/g±10 μg/g明显高于增殖性瘢痕 72 μg/g± 5 μg/g和成人皮肤组织HA的含量 5 1μg/g± 4 μg/g(P <0 0 1) ;胎儿皮肤创伤后 12h ,HA的含量即明显上升 2 83μg/g± 12 μg/g(P <0 0 1) ,在创伤后 3d 32 1μg/g± 12μg/g达到高峰 ,持续至创伤后 1周。成人皮肤创伤后HA的含量较之正常成人皮肤亦显著升高 (P <0 0 1) ;增生性瘢痕中HA的含量介于二者之间 ,与二者之间的差异均有显著意义 (均P <0 0 1)。胎儿皮肤组织CD4 4的含量明显高于增生性瘢痕和成人皮肤组织 (P <0 0 1) ;胎儿皮肤创伤后 2 4h ,CD4 4的含量即明显下降持续至创伤后 1周。成人皮肤创伤后CD4 4的含量较之正常成人皮肤亦有所升高(P <0 0 1) ;增生性瘢痕中CD4 4的含量介于正常成人皮肤和成人皮肤创面CD4 4含量之间 ,与二者之间的差异均有显著意义 (均P <0 0 1)。免疫组化

Expression of hyaluronic acid and its receptor in the process of wound healing in different skin tissues and its significance

OBJECTIVE: To explore the expression of hyaluronic acid (HA) and its receptor, Cluster of differentiation 44 (CD44) in proliferative scar and in the process of wound healing of normal human adult skin and fetal skin, and the effect of HA and its receptor on the process of human fetal skin scarless healing. METHODS: An incision and then a hypodermic cavity were made on each side of the dorsal median line of 32 female adult BALB/c rats. Skin grafts from 8 human fetuses delivered by natural abortion, full-thickness skin grafts from 8 normal adults undergoing plastic operation, skin wound sample from the donor sites in legs of 8 patients undergoing dermatoplasty with intermediate split thickness skin graft, and proliferative scar from 8 patients of plastic surgery, non-adult and adult, were grafted into the hypodermic cavities. The levels of HA and its receptor were examined by radioimmunoassay, immunohistochemistry and flow cytometry. RESULTS: The level of HA in normal fetal skin was 143 micro g/g +/- 10 micro g/g, 283 micro g/g +/- 12 micro g/g 12 hours after injury, 315 micro g/g +/- 12 micro g/g one days after injury, reached the peak (321 micro g/g +/- 12 micro g/g) 3 days after injury, and then decrease, became 319 micro g/g +/- 11 micro g/g one week after injury (P > 0.05 in comparison with that 3 days after injury). The level of HA in normal fetal skin was 143 micro g/g +/- 10 micro g/g, significantly higher than that in normal adult skin (51 micro g/g +/- 4 micro g/g), skin wound of normal adult (92 micro g/g +/- 6 micro g/g), and proliferative scar (72 micro g/g +/- 5 micro g/g, all P < 0.01). The level of HA in wounded adult skin was significantly higher than that in the proliferative scar, and even much higher than that in normal skin (P < 0.01). The level of CD44 in normal fetal skin was significantly higher than that in proliferative scar and adult skin (all P < 0.01). The level of CD44 in wounded fetal skin 24 hours after injury decreased, significantly lower than that in normal fetal skin. There was no statistically significant difference between the level of CD44 in fetal skin one week after injury and that 24 hours after injury (P > 0.05). The level of CD44 in wounded adult skin was significantly higher than that in the normal adult skin (P < 0.01). The level of CD44 in the proliferative scar was between the level of CD44 in normal adult skin and that in wounded adult one. In normal fetal skin, CD44, positively stained at a moderate level, was distributed in keratinized cells, basic cells of hair follicle, and fibroblast of dermis. After injury, staining of CD44 became milder, especially by the incision. Immunohistochemistry showed that in normal adult skin, CD44 was distributed mainly in fibroblast of dermis and basic cells of hair follicle, weakly positively stained. After injury, the staning became stronger. CONCLUSION: The expression of HA and its receptor during the process of wound healing in human fetal skin is different from that in proliferative scars and adult skin, which might be one of the important causes of scarless healing of wounded fatal skin.