Shikhman A R, Cunningham M W
Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City 73104.
J Immunol. 1994 May 1;152(9):4375-87.
We discovered recently that a subset of mouse anti-streptococcal mAbs cross-reacted with N-acetyl-beta-D-glucosamine (GlcNAc) and certain cytoskeletal proteins, and recognized both carbohydrate and peptide antigenic determinants. To further study the nature and biologic significance of immunologic mimicry between carbohydrate and peptide Ags, eight human hybridomas secreting anti-GlcNAc mAbs were produced by in vitro stimulation of PBL with streptococcal peptidoglycan-polysaccharide complexes and pokeweed mitogen. All human anti-GlcNAc mAbs described in this study were shown to express marked cross-reactivity with keratin from human skin in the ELISA and Western immunoblot. Mapping of the mAbs with overlapping synthetic decapeptides of the entire amino acid sequence of human cytokeratin 14 revealed that human anti-GlcNAc mAbs recognized specific cytokeratin decapeptides. Four human anti-GlcNAc mAbs recognized a single cytokeratin decapeptide whereas two mAbs reacted with several individual peptide epitopes in different fragments of cytokeratin 14. In addition, two mAbs, 1.C8 and 9.B12, reacted with multiple cytokeratin decapeptides, predominantly in the head domain of the molecule, and their reactivity correlated with positive binding of the mAbs to cytokeratin 14 in the Western immunoblot and with positive staining of human epidermis in the indirect immunofluorescent assay. Finally, we demonstrated that Abs to keratin and synthetic keratin decapeptides were induced in BALB/c mice immunized with GlcNAc-BSA but not with BSA, suggesting that the anti-keratin Ab response in vivo may be driven by nonkeratin Ags containing terminal O-linked GlcNAc.
我们最近发现，一部分小鼠抗链球菌单克隆抗体与N-乙酰-β-D-葡萄糖胺（GlcNAc）和某些细胞骨架蛋白发生交叉反应，并识别碳水化合物和肽抗原决定簇。为了进一步研究碳水化合物和肽抗原之间免疫模拟的本质和生物学意义，通过用链球菌肽聚糖-多糖复合物和商陆有丝分裂原体外刺激外周血淋巴细胞，产生了8株分泌抗GlcNAc单克隆抗体的人杂交瘤。本研究中描述的所有人抗GlcNAc单克隆抗体在ELISA和Western免疫印迹中均显示与人类皮肤角蛋白有明显的交叉反应。用人细胞角蛋白14的整个氨基酸序列的重叠合成十肽对单克隆抗体进行图谱分析，结果显示人抗GlcNAc单克隆抗体识别特定的细胞角蛋白十肽。4株人抗GlcNAc单克隆抗体识别单个细胞角蛋白十肽，而2株单克隆抗体与细胞角蛋白14不同片段中的几个单独肽表位发生反应。此外，2株单克隆抗体1.C8和9.B12与多个细胞角蛋白十肽发生反应，主要在分子的头部结构域，它们的反应性与Western免疫印迹中该单克隆抗体与细胞角蛋白14的阳性结合以及间接免疫荧光试验中人类表皮的阳性染色相关。最后，我们证明，用GlcNAc-BSA免疫BALB/c小鼠可诱导产生抗角蛋白抗体和合成角蛋白十肽抗体，而用BSA免疫则不能，这表明体内抗角蛋白抗体反应可能由含有末端O-连接GlcNAc的非角蛋白抗原驱动。
