Liu T, Zhou X, Abdel-Motal U M, Ljunggren H G, Jondal M
Microbiology and Tumor Biology Center, Karolinska Institute, Stockholm, Sweden.
Scand J Immunol. 1997 May;45(5):527-33. doi: 10.1046/j.1365-3083.1997.d01-434.x.
T2Kb cells, which do not express TAP1/2 peptide transporters or the low molecular weight protein 2/7 (LMP2/7) proteasomal subunits, can still process and present both live and heat-inactivated Sendai virus (SV). As this operation may also reflect the existence of an alternative processing pathway in normal antigen-presenting cells (APC), the authors have characterized it using intracellular inhibitors and anti-Kb monoclonal antibodies (MoAbs). From the results with lipophilic amines (ammonium chloride, methylamine and chloroquine), cytoskeletal inhibitors (cytochalasin B and vinblastine), and an endoprotease inhibitor (phenylmethylsulfonyl fluoride, PMSF), the authors conclude that the processing of SV antigen in T2Kb cells has endosomal characteristics depending on cellular activities such as uptake, vesicular transport and intracellular-vesicular proteolysis. In addition, internalized 'empty' Kb molecules derived from the T2Kb cell surface appeared to be involved in the presentation of SV antigen, as demonstrated by a protocol using a combination of the Golgi inhibitor brefeldin A(BFA) and anti-Kb antibodies. The results thus indicate that T2Kb cells process SV antigen in an endosomal-like compartment which contain recycling 'empty' Kb molecules.
T2Kb细胞不表达TAP1/2肽转运体或低分子量蛋白2/7（LMP2/7）蛋白酶体亚基，但仍能处理并呈递活的和热灭活的仙台病毒（SV）。由于这一过程可能也反映了正常抗原呈递细胞（APC）中存在替代处理途径，作者使用细胞内抑制剂和抗Kb单克隆抗体（MoAb）对其进行了表征。根据亲脂性胺（氯化铵、甲胺和氯喹）、细胞骨架抑制剂（细胞松弛素B和长春碱）以及一种内蛋白酶抑制剂（苯甲基磺酰氟，PMSF）的实验结果，作者得出结论，T2Kb细胞中SV抗原的处理具有内体特征，这取决于细胞活动，如摄取、囊泡运输和细胞内囊泡蛋白水解。此外，如使用高尔基体抑制剂布雷菲德菌素A（BFA）和抗Kb抗体的实验方案所示，源自T2Kb细胞表面的内化“空”Kb分子似乎参与了SV抗原的呈递。因此，结果表明T2Kb细胞在含有循环“空”Kb分子的类似内体的区室中处理SV抗原。
