Pletscher M, Pernis B
Eur J Immunol. 1983 Jul;13(7):581-4. doi: 10.1002/eji.1830130713.
The important role of type II antigens of the major histocompatibility complex (Ia and DR) in the antigen presentation and in the antigen-specific cooperation between T and B cells is by now firmly established. Human B lymphoblastoid lines MWE and BL were stained with different fluoresceinated anti-DR antibodies. Not only surface but intracytoplasmic DR structures were brightly stained. The intracellular stain accumulated in a cluster close to the nucleus. Different specificity controls were performed. MWE and BL cells quickly internalize membrane IgM if cross-linked by corresponding antibodies. The intracellular location of the vesicles containing these complexes showed substantial coincidence with DR-positive structures in the paranuclear location. It is speculated that IgM-ligand complexes meet internal DR molecules and are both reexpressed on the plasma membrane to be recognized by primed T cells.
主要组织相容性复合体的II类抗原（Ia和DR）在抗原呈递以及T细胞和B细胞之间的抗原特异性协同作用中的重要作用现已得到确凿证实。用人B淋巴母细胞系MWE和BL与不同的荧光素标记抗DR抗体进行染色。不仅细胞表面而且胞质内的DR结构都被染成亮色。细胞内染色聚集在靠近细胞核的一个簇中。进行了不同的特异性对照。如果通过相应抗体交联，MWE和BL细胞会迅速内化膜IgM。含有这些复合物的囊泡在细胞内的位置与核旁位置的DR阳性结构有很大的重合。据推测，IgM-配体复合物与胞内DR分子相遇，并在质膜上重新表达，以供致敏T细胞识别。
