Nakanishi K, Zbar B, Borsos T, Glenn G
Cancer Res. 1986 Aug;46(8):3886-90.
We reported inhibition of growth of primary rat mammary carcinomas after infusions of tumor-bearer plasma absorbed with Protein A-Sepharose or inactivated CNBr Sepharose. Absorbed plasmas were depleted of the third component of complement (C3) (other complement components defined similarly) and C5 but not C1, C4, or C2. These results suggested that activation of the alternative pathway of complement might be involved in the observed antitumor effects. To test this concept sera were treated with ethylenedinitrilotetraacetic acid or [ethylenebis(oxyethylenenitrilo)]tetraacetic acid before absorption with Protein A-Sepharose. Ethylenedinitrilotetraacetic acid, by chelating calcium and magnesium, prevents activation of both the alternative and classical complement pathways. [Ethylenebis(oxyethylenenitrilo)]tetraacetic acid, by chelating calcium but not magnesium, permits activation of the alternative pathway but inhibits activation of the classical complement pathway. Sera in the presence or absence of chelating agent were absorbed with Protein A-Sepharose twice at room temperature. After absorption calcium was added to the sera. Rats were treated by i.v. injection of sera twice a week for 2 weeks. Measurements of tumor size were made weekly for 5-7 weeks and then tumor weight was determined. Groups were compared both for size of index and total tumors. The results can be summarized as follows: tumor-bearer sera before absorption did not inhibit the growth of rat primary mammary carcinomas; tumor-bearer sera after absorption with Protein A-Sepharose showed significant consumption of C3 and did inhibit tumor growth; tumor-bearer sera absorbed in the presence of ethylenedinitrilotetraacetic acid did not show a decrease in C3 functional activity and did not inhibit tumor growth; tumor-bearer sera absorbed in the presence of [ethylenebis(oxyethylenenitrilo)]tetraacetic acid did show a decrease in C3 functional activity and did inhibit tumor growth; sera from normal adult female rats after absorption with Protein A-Sepharose did inhibit tumor growth. The results are consistent with a role for the alternative pathway of complement in the inhibition of growth of rat primary mammary carcinomas observed after treatment with absorbed sera.
我们报道了在输注用蛋白A-琼脂糖或经溴化氰处理的琼脂糖吸收的荷瘤大鼠血浆后，大鼠原发性乳腺癌的生长受到抑制。吸收后的血浆中补体第三成分（C3）（其他补体成分定义类似）和C5减少，但C1、C4或C2未减少。这些结果表明，补体替代途径的激活可能与观察到的抗肿瘤作用有关。为了验证这一概念，在将血清用蛋白A-琼脂糖吸收之前，先用乙二胺四乙酸或[乙二双（氧乙基亚氨基）]四乙酸处理血清。乙二胺四乙酸通过螯合钙和镁，可防止替代途径和经典补体途径的激活。[乙二双（氧乙基亚氨基）]四乙酸通过螯合钙而非镁，可使替代途径激活，但抑制经典补体途径的激活。在有或无螯合剂存在的情况下，血清在室温下用蛋白A-琼脂糖吸收两次。吸收后向血清中添加钙。大鼠通过静脉注射血清每周两次，共2周进行治疗。每周测量肿瘤大小5至7周，然后测定肿瘤重量。比较各实验组的指数肿瘤和总肿瘤大小。结果总结如下：吸收前的荷瘤大鼠血清不抑制大鼠原发性乳腺癌的生长；用蛋白A-琼脂糖吸收后的荷瘤大鼠血清显示C3显著消耗且确实抑制肿瘤生长；在乙二胺四乙酸存在下吸收的荷瘤大鼠血清未显示C3功能活性降低且不抑制肿瘤生长；在[乙二双（氧乙基亚氨基）]四乙酸存在下吸收的荷瘤大鼠血清确实显示C3功能活性降低且确实抑制肿瘤生长；用蛋白A-琼脂糖吸收后的正常成年雌性大鼠血清确实抑制肿瘤生长。这些结果与补体替代途径在经吸收血清治疗后观察到的大鼠原发性乳腺癌生长抑制中所起的作用一致。
