Timonen T, Ortaldo J R, Herberman R B
J Exp Med. 1981 Mar 1;153(3):569-82. doi: 10.1084/jem.153.3.569.
Recent evidence, has demonstrated an association between a subpopulation of peripheral blood mononuclear cells, morphologically identified as large granular lymphocytes (LGL), and natural killer (NK) activity. We have now evaluated more directly the role of LGL in both NK activity and antibody- dependent cellular cytotoxicity (ADCC), by using highly enriched populations of LGL, obtained by centrifugation of peripheral blood mononuclear cells on Percoll discontinuous density gradients. Both spontaneous and interferon- augmented NK and ADCC activities were exclusively associated with the LGL- enriched, low density fractions. The majority of LGL formed conjugates with NK-susceptible and antibody-coated target cells. Approximately 20 percent of small conventional lymphocytes also formed conjugates with the target cells for NK, but this was not associated with cytotoxic activity. Virtually all LGL were found to have receptors for the Fc portion of IgG (FcgammaR). The frequency of LGL among blood leukocytes was 2-6 percent. LGL could be enriched to an average purity of 95 percent by combining discontinuous density gradient centrifugation with subsequent adsorptions of the low density fractions on monolayers of immobilized immune complexes. About 50 percent of LGL were found to be FcgammaR-bearing T cells (T(G)), forming low affinity rosettes with sheep erythrocytes at 4 degrees C. Only 10-20 percent of LGL formed high affinity rosettes with sheep erythrocytes at 29 degrees C. LGL could be enriched to a purity of more than 90 percent by depleting high affinity rosette-forming cells from low density Percoll fractions. LGL were only a subpopulation of T(G) cells, because some lymphocytes with conventional morphology also adhered to the immobilized immune complex monolayers and formed high affinity rosettes with sheep erythrocytes. Separation of these cells from LGL by discontinuous density gradient centrifugation indicated that they are not cytotoxic, suggesting a morphological and functional subdivision of T(G) cells. The verification in this study that virtually all human NK and K cells have a characteristic morphology adds a useful parameter to the monitoring of human lymphocytes, and the ability to purify these cells by simple physical procedures should be invaluable in their further characterization.
最近的证据表明，在外周血单个核细胞亚群（形态学上鉴定为大颗粒淋巴细胞，即LGL）与自然杀伤（NK）活性之间存在关联。现在，我们通过使用通过在Percoll不连续密度梯度上离心外周血单个核细胞获得的高度富集的LGL群体，更直接地评估了LGL在NK活性和抗体依赖性细胞毒性（ADCC）中的作用。自发的和干扰素增强的NK及ADCC活性均仅与富含LGL的低密度组分相关。大多数LGL与NK敏感且被抗体包被的靶细胞形成结合物。约20%的小的传统淋巴细胞也与NK靶细胞形成结合物，但这与细胞毒性活性无关。实际上，所有LGL都被发现具有IgG的Fc部分（FcγR）的受体。血液白细胞中LGL的频率为2% - 6%。通过将不连续密度梯度离心与随后将低密度组分吸附到固定化免疫复合物单层上相结合，LGL可富集至平均纯度为95%。约50%的LGL被发现是带有FcγR的T细胞（T(G)），在4℃时与绵羊红细胞形成低亲和力花环。只有10% - 20%的LGL在29℃时与绵羊红细胞形成高亲和力花环。通过从低密度Percoll组分中去除形成高亲和力花环的细胞，LGL可富集至纯度超过90%。LGL只是T(G)细胞的一个亚群，因为一些具有传统形态的淋巴细胞也粘附于固定化免疫复合物单层并与绵羊红细胞形成高亲和力花环。通过不连续密度梯度离心将这些细胞与LGL分离表明它们无细胞毒性，提示T(G)细胞存在形态学和功能上的细分。本研究证实实际上所有人类NK和K细胞都具有特征性形态，这为监测人类淋巴细胞增加了一个有用的参数，并且通过简单物理程序纯化这些细胞的能力在其进一步表征中应具有极高价值。
