Development of a new treatment strategy for wound healing using recombinant type VII collagen

III型胶原是一种非纤维性胶原，是在表皮基底膜下锚定原纤维结构的主要成分，对皮肤基底膜区的完整性至关重要。III型胶原基因突变与营养不良的大疱性表皮松解症(DEB)有关，DEB是一组以皮肤脆性为特征的机械性延髓疾病，容易形成基底板下致密层水泡。DEB组创面愈合延迟。本研究的目的是阐明重组III型胶原对创面愈合的治疗作用。首先，我们纯化了大量的重组III型胶原。我们将VII型胶原基因导入HaCaT细胞、NIH3T3细胞和293细胞，通过G418.293细胞进行稳定转化子的筛选，其中293细胞主要表达VII型胶原。我们可以显示来自VII型胶原基因敲除小鼠和DEB患者的角质形成细胞和成纤维细胞的流动性低，但加入重组的VII型胶原可以挽救流动性受损的情况。此外，将重组VII型胶原应用于皮肤溃疡可促进创面愈合，我们建议将VII型胶原作为一种抗溃疡药物。因此，我们认为可以建立一种利用重组VII型胶原治疗创面的新策略。

Type VII collagen, a non-fibrillar collagen, is a major component of anchoring fibril structures beneath the epidermal basement membrane, and is of critical importance for integrity of the cutaneous basement membrane zone. Mutations within the type VII collagen gene are associated with the dystrophic forms of epidermolysis bullosa (DEB), a group of mechanobullous diseases characterized by cutaneous fragility and tendency to form sub-basal lamina densa blisters. The patients with DEB showed delayd wound healing. The aim of this study was to clarify therapeutic effect of recombinant type VII collagen on wound healing. First, we purified a large amount of recombinant type VII collagen. We introduced the type VII collagen gene into HaCaT cells, NIH3T3 cells and 293 cells and performed selection of stable transformants by G418.293 cells expressed type VII collagen mostly among those cell lines. We could show low mobility of keratinocytes and fibroblasts from type VII collagen-gene knockout mouse and DEB patients, but addtion of recombinant type VII collagen rescued impaired mobility. Furthermore, application of recombinant type VII collagen to skin ulcer improved wound healing and we proposed type VII collagen as an anti-ulcer drug. Thus, we think that we can achieve establishment of a new strategy for treatment of wound using recombinant type VII collagen.