Ferro T J, Monos D S, Spear B T, Rossman M D, Zmijewski C M, Kamoun M, Daniele R P
Am Rev Respir Dis. 1987 Jun;135(6):1340-4. doi: 10.1164/arrd.1987.135.6.1340.
Two-dimensional gel electrophoresis was used to compare immunoprecipitated, radiolabeled HLA-DR molecules synthesized by alveolar macrophages (AM) and blood monocytes (BM) of the same healthy, nonsmoking volunteers. No charge differences were noted by isoelectric focusing. Molecular weight analysis of HLA-DR from AM revealed a complex pattern of radioactive spots differing slightly in molecular weight. This pattern was apparent in both the alpha and the beta chains. In contrast, a simpler pattern without the slight molecular weight differences was noted in HLA-DR from BM. The differences were eliminated by labeling AM and BM in the presence of tunicamycin, a specific inhibitor of protein-carbohydrate linkages of the N-glycosidic type. Thus, it appears that neutral, N-linked carbohydrate moieties account for the differences in HLA-DR molecules between AM and BM. The differential glycosylation of HLA-DR molecules in AM and BM may relate to mononuclear phagocyte development as well as antigen-presenting function.
采用二维凝胶电泳比较了来自相同健康、不吸烟志愿者的肺泡巨噬细胞（AM）和血液单核细胞（BM）合成的免疫沉淀、放射性标记的HLA - DR分子。等电聚焦未发现电荷差异。对来自AM的HLA - DR进行分子量分析，发现放射性斑点的复杂模式，其分子量略有不同。这种模式在α链和β链中均很明显。相比之下，在来自BM的HLA - DR中发现了一种更简单的模式，没有轻微的分子量差异。在衣霉素（一种N - 糖苷型蛋白质 - 碳水化合物连接的特异性抑制剂）存在的情况下标记AM和BM，差异消失。因此，似乎中性的N - 连接碳水化合物部分导致了AM和BM之间HLA - DR分子的差异。AM和BM中HLA - DR分子的差异糖基化可能与单核吞噬细胞的发育以及抗原呈递功能有关。
