DePalma R L, Krummel T M, Durham L A, Michna B A, Thomas B L, Nelson J M, Diegelmann R F
Department of Surgery, Medical College of Virginia, Virginia Commonwealth University, Richmond 23298.
Matrix. 1989 Jun;9(3):224-31. doi: 10.1016/s0934-8832(89)80054-x.
Fetal response to injury has been characterized by the deposition of a matrix that is not primarily collagen. This study was designed to identify this matrix, in order to better understand the fetal mechanism of tissue repair. Silastic/polyvinyl alcohol sponge (PVA) wound implants were placed paravertebrally in 24-day gestation (31 days = term) fetal (n = 65) and adult (n = 43) rabbits and then harvested from one hour to 6 days post-wounding. Histologic analysis of the fetal wound matrix deposited in the PVA implants suggested the presence of glycosaminoglycans (GAG) rather than the collagen found in adult wound implants. To further analyze the fetal wound matrix, the GAG content was quantitated using an Alcian Blue dye-binding assay. Results showed significantly increased (p less than 0.05) GAG deposition on days 2-6 in the fetal wound compared to the adult wound. Fetal GAG levels were approximately three times those of the adult during this period. Separation of individual GAG species by cellulose acetate electrophoresis demonstrated that the GAG matrix of the fetal wound was composed predominantly of hyaluronic acid. This finding was confirmed by selective enzymatic digestion of separated GAG species using highly specific polysaccharidases. These observations of hyaluronic acid deposition in the fetal wound may be ascribed an important physiologic role by providing a more fluid and malleable matrix rather than a restrictive matrix composed of collagen. This new evidence coupled with earlier findings of the lack of an acute inflammatory response in the fetus further supports the hypothesis that the fetal response to injury is significantly different from the adult response.
胎儿对损伤的反应特征是形成一种并非主要由胶原蛋白构成的基质。本研究旨在识别这种基质，以便更好地理解胎儿组织修复机制。将硅橡胶/聚乙烯醇海绵（PVA）伤口植入物置于妊娠24天（足月为31天）的胎儿（n = 65）和成年（n = 43）兔的椎旁，然后在受伤后1小时至6天进行取材。对PVA植入物中沉积的胎儿伤口基质进行组织学分析表明，存在糖胺聚糖（GAG），而非成年伤口植入物中发现的胶原蛋白。为进一步分析胎儿伤口基质，使用阿尔新蓝染料结合测定法定量GAG含量。结果显示，与成年伤口相比，胎儿伤口在第2 - 6天的GAG沉积显著增加（p小于0.05）。在此期间，胎儿的GAG水平约为成年的三倍。通过醋酸纤维素电泳分离单个GAG种类表明，胎儿伤口的GAG基质主要由透明质酸组成。使用高度特异性的多糖酶对分离的GAG种类进行选择性酶消化证实了这一发现。胎儿伤口中透明质酸沉积的这些观察结果可能具有重要的生理作用，因为它提供了一种更具流动性和可塑性的基质，而非由胶原蛋白构成的限制性基质。这一新证据加上早期关于胎儿缺乏急性炎症反应的发现，进一步支持了胎儿对损伤的反应与成年反应显著不同的假说。
