Peltonen J, Jaakkola S, Hsiao L L, Timpl R, Chu M L, Uitto J
Department of Dermatology, Jefferson Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania.
Lab Invest. 1990 Apr;62(4):487-92.
Cutaneous neurofibromas contain an extensive extracellular matrix composed of collagenous and non-collagenous macromolecules. In this study, the expression of type VI collagen genes in cutaneous neurofibromas was examined by a combination of in situ hybridizations and immunohistochemistry. In situ hybridizations with a 32P-labeled human type VI collagen-specific cDNA revealed that the majority of cells within neurofibromas expressed the gene for alpha 2(VI) collagen chain. The number of cells expressing clearly detectable levels of alpha 2(VI) collagen mRNA was considerably higher than that of cells actively expressing the pro alpha 1(I) or pro alpha 1(III) collagen genes. The presence of type VI collagen epitopes within the neurofibromas was also demonstrated by immunostaining with specific polyclonal antibodies. The expression of type VI collagen genes in neural tissues was further examined by immunostaining of a benign schwannoma tissue specimen consisting of Schwann cells. The results indicated close association of type VI collagen epitopes with the neoplastic Schwann cells. Immunolocalization of type VI collagen epitopes within normal human peripheral nerve revealed pericellular staining of perineurial cells and Schwann cells, suggesting synthesis of type VI collagen by these cell types. These results suggest that the expression of type VI collagen gene is active in nerve-derived tissues, and that type VI collagen may be a major component of the extracellular matrix in neural connective tissues.
皮肤神经纤维瘤含有由胶原和非胶原大分子组成的广泛细胞外基质。在本研究中，通过原位杂交和免疫组织化学相结合的方法检测了皮肤神经纤维瘤中VI型胶原基因的表达。用32P标记的人VI型胶原特异性cDNA进行原位杂交显示，神经纤维瘤内的大多数细胞表达α2(VI)胶原链基因。表达明显可检测水平的α2(VI)胶原mRNA的细胞数量明显高于积极表达原α1(I)或原α1(III)胶原基因的细胞数量。用特异性多克隆抗体进行免疫染色也证实了神经纤维瘤内存在VI型胶原表位。通过对由施万细胞组成的良性神经鞘瘤组织标本进行免疫染色，进一步检测了神经组织中VI型胶原基因的表达。结果表明VI型胶原表位与肿瘤性施万细胞密切相关。在正常人周围神经中VI型胶原表位的免疫定位显示，神经束膜细胞和施万细胞有细胞周染色，提示这些细胞类型可合成VI型胶原。这些结果表明，VI型胶原基因在神经源性组织中表达活跃，并且VI型胶原可能是神经结缔组织细胞外基质的主要成分。
