Silagi S, Dutkowski R, Schaefer A
Department of Obstetrics and Gynecology, Cornell University Medical College, New York, NY 10021.
Int J Cancer. 1988 Feb 15;41(2):315-22. doi: 10.1002/ijc.2910410225.
Successful immunotherapy of early s.c. or i.p. (B16) melanoma in syngeneic C57BL/6 (B6) mice was achieved with s.c. peri-lesional injections (for s.c. tumors) or i.p. injections (for i.p. tumors) of recombinant human interleukin 2 (rIL-2) and recombinant murine interferon-gamma (rIFN-gamma). Over a 28-day period, rIL-2 and rIFN-gamma were injected 14 times. Results with this combination were additive with s.c. tumors and synergistic with i.p. tumors. Treatment with 6,250 U-25,000 U of rIL-2 and 2 micrograms of rIFN-gamma began 1-3 days after s.c. inoculation of melanoma. On day 50, 87% (72/83) of mice thus treated were completely free of tumor. None of the 78 control mice (tumor + buffer) survived. Of mice receiving either rIL-2 or rIFN-gamma alone, 59% (47/79) and 53% (44/83), respectively, were tumor-free. I.p. tumors were also eradicated by i.p. injections of rIL-2 (50,000 U) with rIFN-gamma (5, 10, and 15 micrograms) as judged by absence of tumor in 81% (21/26) of mice autopsied between days 45 and 65. No control mice survived, and only 17% (2/12) and 20% (6/30) given either rIL-2 or rIFN-gamma separately (i.p.) were tumor-free. Doses of rIFN-gamma from 1-4 micrograms were more beneficial in eliminating 1-day s.c. melanomas than were higher doses, and local s.c. treatment was far superior to distant or systemic treatment. Non-adherent peritoneal or splenic cells from mice bearing 6-day-old i.p. melanomas and treated with one or both lymphokines on days 3 and 4 were used in cytotoxicity assays in vitro. Significant cytotoxicity against cultured melanoma cells was displayed by cells harvested from lymphokine-treated mice, but there was no evidence of the synergism observed with combination treatment of i.p. tumors in vivo. rIFN-gamma inhibited proliferation of melanoma cells in vitro, whereas rIL-2 stimulated proliferation at 1,000 U/ml. Plating efficiency was increased by at least 30% by culture with 100 U or 1,000 U of rIL-2/ml and both concentrations neutralized the inhibitory effect of 0.05 ng/ml of IFN-gamma, but not of 0.5 or 5.0 ng/ml.
通过在同基因C57BL/6（B6）小鼠中对早期皮下或腹腔内（B16）黑色素瘤进行成功的免疫治疗，方法是对皮下肿瘤进行皮下病灶周围注射，对腹腔内肿瘤进行腹腔内注射重组人白细胞介素2（rIL-2）和重组鼠干扰素-γ（rIFN-γ）。在28天的时间里，rIL-2和rIFN-γ共注射14次。这种联合治疗对皮下肿瘤的效果是相加的，对腹腔内肿瘤是协同的。在皮下接种黑色素瘤后1 - 3天开始用6250 U - 25000 U的rIL-2和2微克的rIFN-γ进行治疗。在第50天，接受这种治疗的小鼠中有87%（72/83）完全没有肿瘤。78只对照小鼠（肿瘤 + 缓冲液）全部死亡。单独接受rIL-2或rIFN-γ治疗的小鼠中，分别有59%（47/79）和53%（44/83）没有肿瘤。腹腔内注射rIL-2（50000 U）与rIFN-γ（5、10和15微克）也能根除腹腔内肿瘤，在第45天至65天之间解剖的小鼠中，81%（21/26）没有肿瘤。没有对照小鼠存活，单独腹腔内给予rIL-2或rIFN-γ的小鼠中分别只有17%（2/12）和20%（6/30）没有肿瘤。1 - 4微克的rIFN-γ剂量在消除1天龄的皮下黑色素瘤方面比更高剂量更有益，局部皮下治疗远优于远处或全身治疗。对在第3天和第4天用一种或两种淋巴因子治疗的、患有6天龄腹腔内黑色素瘤的小鼠，取其非贴壁腹膜或脾细胞进行体外细胞毒性测定。从接受淋巴因子治疗的小鼠中收获的细胞对培养的黑色素瘤细胞显示出显著的细胞毒性，但没有证据表明在体内对腹腔内肿瘤进行联合治疗时观察到的协同作用。rIFN-γ在体外抑制黑色素瘤细胞的增殖，而rIL-2在1000 U/ml时刺激增殖。用100 U或1000 U/ml的rIL-2培养可使接种效率提高至少30%，这两种浓度都能中和0.05 ng/ml IFN-γ的抑制作用，但不能中和0.5或5.0 ng/ml IFN-γ的抑制作用。
