Lu W, Pipeleers D G, Klöppel G, Bouwens L
Department of Experimental Pathology, Free University of Brussels, Belgium.
Virchows Arch. 1996 Nov;429(4-5):205-11. doi: 10.1007/BF00198335.
Expression of major histocompatibility complex (MHC) molecules by pancreatic islets may influence the survival of pancreas or islet grafts in allogeneic recipients. This study compares the presence of MHC class II (HLA-DP, DQ, DX and DR)-positive cells in 27 pancreases and in 10 isolated islet preparations from human donors. Cells expressing MHC class II were present in all tissues examined as histiocytes located in interstitial areas in both the endocrine and nonendocrine components and as endothelial cells in the nonendocrine part. Endocrine, acinar and duct cells were MHC class II negative. In pancreases from donors under the age of 7 years the frequency of MHC class II-positive histiocytes was only one third of that in adults, and they rarely contained MHC class II-positive endothelial cells. The MHC class II-positive histiocytes were further phenotyped as macrophages positive for LCA and acid phosphatase, or dendritic cells negative for the latter markers. Dendritic cells were frequent in adult organs but rare in organs from donors under 7 years of age. In freshly isolated islet preparations from adult donors, less than 1% of the cells were MHC class II positive. These were identified as resident macrophages and dendritic cells. No MHC class II positive cells were encountered in the islet capillaries. The putative role of MHC class II-positive donor cells in allograft rejection suggests that these differences in MHC class II expression influence the immunogenicity of pancreatic and islet grafts in an age-dependent manner.
胰岛中主要组织相容性复合体（MHC）分子的表达可能会影响同种异体受体中胰腺或胰岛移植的存活。本研究比较了27个胰腺和10份来自人类供体的分离胰岛制剂中MHC II类（HLA-DP、DQ、DX和DR）阳性细胞的存在情况。表达MHC II类的细胞存在于所有检查的组织中，在内分泌和非内分泌成分的间质区域以组织细胞形式存在，在非内分泌部分以内皮细胞形式存在。内分泌细胞、腺泡细胞和导管细胞为MHC II类阴性。在7岁以下供体的胰腺中，MHC II类阳性组织细胞的频率仅为成年人的三分之一，且它们很少含有MHC II类阳性内皮细胞。MHC II类阳性组织细胞进一步表型化为LCA和酸性磷酸酶阳性的巨噬细胞，或后一种标记物阴性的树突状细胞。树突状细胞在成人器官中常见，但在7岁以下供体的器官中罕见。在来自成年供体的新鲜分离胰岛制剂中，不到1%的细胞为MHC II类阳性。这些细胞被鉴定为驻留巨噬细胞和树突状细胞。在胰岛毛细血管中未发现MHC II类阳性细胞。MHC II类阳性供体细胞在同种异体移植排斥中的假定作用表明，这些MHC II类表达的差异以年龄依赖性方式影响胰腺和胰岛移植的免疫原性。
