Baines M G, Lafleur F L, Holbein B E
Immunol Lett. 1983;7(1):51-5. doi: 10.1016/0165-2478(83)90055-x.
In this current study one of the determinants of natural killer cell specificity in immunosurveillance against cancer, may be the recognition of transferrin receptors on neoplastic cells by the NK effectors. Human transferrin, when saturated with iron (FeTf), was found to inhibit human natural killer (NK) activity against K562 tumor cells, if included in assay mixtures at physiologically relevant levels. Whereas both FeTf and iron-free transferrin (ApoTf) inhibited initial conjugate formation at the level of the target cell, only FeTf inhibited NK cytolytic activity, as judged by release of chromium from the targets. This suggested a functional role for FeTf on either NK or tumor cells. When either targets or effector lymphocytes were pre-incubated with FeTf, inhibition of killing was strongest when the targets were first exposed to FeTf. The evidence suggested that NK-associated transferrin mediated the interaction with target cells through free target-associated transferrin receptors. The finding that rabbit anti-human transferrin antibody (RaHTf) inhibited killing, when reacted with effector lymphocytes but not with target cells, supported this hypothesis.
在当前这项研究中，免疫监视针对癌症时自然杀伤细胞特异性的决定因素之一，可能是自然杀伤效应细胞对肿瘤细胞上转铁蛋白受体的识别。当人转铁蛋白与铁饱和（FeTf）时，如果以生理相关水平包含在检测混合物中，发现其会抑制人自然杀伤（NK）细胞对K562肿瘤细胞的活性。尽管FeTf和无铁转铁蛋白（ApoTf）在靶细胞水平均抑制初始结合物的形成，但从靶细胞释放铬来判断，只有FeTf抑制NK细胞的溶细胞活性。这表明FeTf在NK细胞或肿瘤细胞上具有功能作用。当靶细胞或效应淋巴细胞与FeTf预孵育时，若靶细胞首先接触FeTf，杀伤抑制作用最强。证据表明，与NK相关的转铁蛋白通过游离的与靶细胞相关的转铁蛋白受体介导与靶细胞的相互作用。兔抗人转铁蛋白抗体（RaHTf）与效应淋巴细胞而非靶细胞反应时抑制杀伤作用这一发现支持了该假说。
