Multhoff G, Pfister K, Botzler C, Jordan A, Scholz R, Schmetzer H, Burgstahler R, Hiddemann W
Department of Hematology and Oncology, University Hospital Regensburg, Regensburg, Germany.
Int J Cancer. 2000 Dec 1;88(5):791-7. doi: 10.1002/1097-0215(20001201)88:5<791::aid-ijc17>3.0.co;2-i.
In vitro, tumor-selective Hsp70 plasma membrane localization correlates with increased sensitivity to lysis mediated by a subpopulation of human natural killer (NK) cells that adhere to plastic following cytokine stimulation. In the present study, we analyzed the capacity of adoptively transferred human NK cells in SCID/beige mice for local tumor control and prevention of metastatic dissemination of Hsp70-expressing CX(+) and non-expressing CX(-) tumors following orthotopic (o.t.) injection. Both tumor sublines were derived by cell sorting of the original cell line, CX2, and thus exhibit an identical MHC and adhesion molecule expression pattern but differ with respect to Hsp70 plasma membrane expression. Viability of adherent, human NK cells in SCID/beige mice up to 18 days and the capacity to migrate have been demonstrated. Growth of Hsp70-expressing and non-expressing CX(+) and CX(-) tumor cells was completely suppressed when 10 x 10(6) NK cells were injected into the i.p. cavity on day 4 after inoculation of 2.5 x 10(6) tumor cells. Although a single injection of 5 or 2.5 x 10(6) NK cells was not sufficient to suppress tumor growth completely in all mice, the reduction in size of CX(+) tumors was significantly greater than that of CX(-) tumors. To mimic the clinical situation, ex vivo stimulated NK cells were injected i.v. on day 4 after o.t. injection of tumor cells. Under these conditions, growth of Hsp70-expressing primary tumors and metastases was suppressed. If CX(-) tumor cells were injected, 3 of 9 mice developed Hsp70-negative primary tumors. However, none of these mice developed distant metastases. In summary, our data indicate that Hsp70 acts as a recognition structure for adherent NK cells in a SCID/beige mouse model.
在体外，肿瘤选择性热休克蛋白70（Hsp70）的质膜定位与对由细胞因子刺激后粘附于塑料的人类自然杀伤（NK）细胞亚群介导的裂解敏感性增加相关。在本研究中，我们分析了在SCID/米色小鼠中过继转移的人类NK细胞对原位（o.t.）注射后表达Hsp70的CX(+)和不表达Hsp70的CX(-)肿瘤进行局部肿瘤控制和预防转移扩散的能力。这两种肿瘤亚系均通过对原始细胞系CX2进行细胞分选获得，因此具有相同的主要组织相容性复合体（MHC）和粘附分子表达模式，但在Hsp70质膜表达方面存在差异。已证实SCID/米色小鼠中粘附的人类NK细胞在长达18天内的活力及其迁移能力。在接种2.5×10(6)个肿瘤细胞后第4天，向腹腔内注射10×10(6)个NK细胞时，表达Hsp70和不表达Hsp70的CX(+)和CX(-)肿瘤细胞的生长被完全抑制。尽管单次注射5×10(6)或2.5×10(6)个NK细胞不足以在所有小鼠中完全抑制肿瘤生长，但CX(+)肿瘤大小的减小明显大于CX(-)肿瘤。为模拟临床情况，在肿瘤细胞o.t.注射后第4天静脉注射体外刺激的NK细胞。在这些条件下，表达Hsp70的原发性肿瘤和转移瘤的生长受到抑制。如果注射CX(-)肿瘤细胞，9只小鼠中有3只出现了Hsp70阴性的原发性肿瘤。然而，这些小鼠均未发生远处转移。总之，我们的数据表明，在SCID/米色小鼠模型中，Hsp70作为粘附NK细胞的识别结构。
