Lauzon R J, Roder J C
Cell Immunol. 1985 Aug;94(1):85-99. doi: 10.1016/0008-8749(85)90087-5.
In an attempt to investigate the nature of tumor cell-derived membrane surface determinants involved in natural killer cell (NK) recognition or postrecognition events, we have constructed human X mouse interspecies somatic cell hybrids. Highly NK-sensitive (NKs) human tumor cells were fused with NK resistant (NKr) mouse fibroblasts (LMTK-) in polyethylene glycol and selected in hypoxanthine/aminopterin/thymidine medium and ouabain. Hybrids generated from NKs erythroleukemia cells (K-562) or NKs retinoblastoma cells (Y-79) with LMTK- displayed an intermediate NK-sensitive phenotype. One Y-79 X LMTK- hybrid (YL-22) retained a high level of susceptibility to NK binding and cytolysis, as determined by 51Cr release and in cold-target inhibition assays. On the other hand, human NKr RAJI cells generated NK-resistant hybrids when fused with LMTK- fibroblasts. Four hybrids (KL-12, YL-2, YL-22, and YL-43) displaying consistent NK sensitivity were subsequently cloned by limiting dilution. Various hybrid clones derived from the KL-12 hybrid (K-562 X LMTK-) demonstrated a range of NK-sensitive phenotypes. However, the uncloned KL-12 and most cloned lines derived from this hybrid competed against 51Cr-labeled K-562 targets as well as unlabeled K-562 parental cells, regardless of their NK-sensitive phenotype. These findings raise the possibility that chromosomal segregation may be affecting a postbinding step in this hybrid system. The NK-sensitive hybrids exhibited a limited number of human chromosomes as assessed by quinacrine banding. Furthermore, human transferrin receptor (TfR) expression, as monitored by flow cytometry using the B3/25 monoclonal antibody, demonstrated no clear correlation with NK sensitivity or competitive ability in either KL or YL hybrid clones, thus arguing against the involvement of the TfR in human NK recognition. These results suggest that the NK-sensitive phenotype in human tumor cells may be regulated by genes encoded by a limited number of human chromosomes.
为了研究参与自然杀伤细胞（NK）识别或识别后事件的肿瘤细胞衍生膜表面决定簇的性质，我们构建了人×小鼠种间体细胞杂种。高度NK敏感（NKs）的人肿瘤细胞与NK抗性（NKr）的小鼠成纤维细胞（LMTK-）在聚乙二醇中融合，并在次黄嘌呤/氨基蝶呤/胸腺嘧啶核苷培养基和哇巴因中进行筛选。由NKs红白血病细胞（K-562）或NKs视网膜母细胞瘤细胞（Y-79）与LMTK-产生的杂种表现出中间NK敏感表型。通过51Cr释放和冷靶抑制试验确定，一个Y-79×LMTK-杂种（YL-22）对NK结合和细胞溶解保持高水平的敏感性。另一方面，人NKr RAJI细胞与LMTK-成纤维细胞融合时产生NK抗性杂种。随后通过有限稀释法克隆了四个表现出一致NK敏感性的杂种（KL-12、YL-2、YL-22和YL-43）。来自KL-12杂种（K-562×LMTK-）的各种杂种克隆表现出一系列NK敏感表型。然而，未克隆的KL-12以及由此杂种衍生的大多数克隆系与51Cr标记的K-562靶标以及未标记的K-562亲本细胞竞争，无论它们的NK敏感表型如何。这些发现增加了染色体分离可能影响该杂种系统中结合后步骤的可能性。通过喹吖因显带评估，NK敏感杂种显示出有限数量的人类染色体。此外，使用B3/25单克隆抗体通过流式细胞术监测的人转铁蛋白受体（TfR）表达，在KL或YL杂种克隆中与NK敏感性或竞争能力均无明显相关性，因此反对TfR参与人类NK识别。这些结果表明，人肿瘤细胞中的NK敏感表型可能受有限数量人类染色体编码的基因调控。
