The natural killer cell receptor specific for HLA-A allotypes: a novel member of the p58/p70 family of inhibitory receptors that is characterized by three immunoglobulin-like domains and is expressed as a 140-kD disulphide-linked dimer.
The natural killer cell receptor specific for HLA-A allotypes: a novel member of the p58/p70 family of inhibitory receptors that is characterized by three immunoglobulin-like domains and is expressed as a 140-kD disulphide-linked dimer.
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DOI：
10.1084/jem.184.2.505
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发表时间：
1996-08-01
期刊：
影响因子：
--
通讯作者：
Moretta L
中科院分区：
文献类型：
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作者：
Pende D;Biassoni R;Cantoni C;Verdiani S;Falco M;di Donato C;Accame L;Bottino C;Moretta A;Moretta L
人类自然杀伤（NK）细胞表达对不同组的HLA-C或HLA-B等位基因具有特异性的抑制性受体。这些受体中的大多数属于免疫球蛋白（IG）超家族，其特征在于两个或三个胞外Ig样结构域。在这里，我们描述了一种新的抑制性NK受体，是特定的一组HLA-A等位基因。HLA-A3特异性NK细胞克隆DP 7已用于小鼠免疫。两种单克隆抗体，称为Q66和Q241，结合到免疫克隆和染色的NK细胞群或克隆的子集。在Q66 mAb反应性克隆中，我们进一步选择了不表达任何先前鉴定的HLA I类特异性NK受体的克隆。这些克隆不裂解HLA-A3+（或-A11+）靶细胞，但在Q66或Q241 mAb存在下可检测到这些靶细胞的裂解。另一方面，表达其它HLA-A等位基因（包括-A1、-A2和-A24）的靶细胞被有效裂解.此外，所测试的HLA-C或HLA-B等位基因都没有发挥保护作用。Q66+而非Q66- NK细胞克隆表达编码与HLA-C（p58）和HLA-B（p70）受体同源的新型3 IG结构域蛋白的信使RNA。相应的cDNA（cl.1.1）分别用于在COS 7和NIH 3 T3细胞系中产生瞬时和稳定的转染子。两种类型的转染子均被Q66和Q241 mAb特异性染色。由于Q66-反应分子的胞质尾区比其他已知的p58/p70分子长至少11个氨基酸，我们可以产生对Q66-反应分子的COOH-末端具有特异性的抗血清，称为PGP-3。PGP-3免疫沉淀，仅从Q66+ NK细胞，分子显示分子量为140 kD，在非还原条件下，解决，在还原条件下，在70 kD的带。因此，与其他p58/p70受体不同，Q66反应分子似乎表达为二硫键连接的二聚体，因此被称为p140。p58，p70，和p140分子的氨基酸序列的比较分析显示，存在两个半胱氨酸的跨膜区附近，只有在p140分子的氨基酸序列。
Human natural killer (NK) cells express inhibitory receptors that are specific for different groups of HLA-C or HLA-B alleles. The majority of these receptors belong to the immunoglobulin (Ig) superfamily and are characterized by two or three extracellular Ig-like domains. Here we describe a novel inhibitory NK receptor that is specific for a group of HLA-A alleles. The HLA-A3-specific NK cell clone DP7 has been used for mice immunization. Two mAbs, termed Q66 and Q241, bound to the immunizing clone and stained only a subset of NK cell populations or clones. Among Q66 mAb-reactive clones, we further selected those that did not express any of the previously identified HLA-class I-specific NK receptors. These clones did not lyse HLA-A3+ (or -A11+) target cells, but lysis of these targets could be detected in the presence of Q66 or Q241 mAbs. On the other hand, target cells expressing other HLA- A alleles, including -A1, -A2, and -A24, were efficiently lysed. Moreover, none of the HLA-C or HLA-B alleles that were tested exerted a protective effect. Q66+, but not Q66- NK cell clones, expressed messenger RNA coding for a novel 3 Ig domain protein homologous to the HLA-C (p58) and HLA-B (p70) receptors. The corresponding cDNA (cl.1.1) was used to generate transient and stable transfectants in COS7 and NIH3T3 cell lines, respectively. Both types of transfectants were specifically stained by Q66 and Q241 mAbs. Since the cytoplasmic tail of Q66-reactive molecules was at least 11 amino acid longer than the other known p58/p70 molecules, we could generate an antiserum specific for the COOH-terminus of Q66-reactive molecules, termed PGP-3. PGP-3 immunoprecipitated, only from Q66+ NK cells, molecules displaying a molecular mass of 140 kD, under nonreducing conditions, which resolved, under reducing conditions, in a 70-kD band. Thus, differently from the other p58/p70 receptors, Q66-reactive molecules appear to be expressed as disulphide-linked dimers and were thus termed p140. The comparative analysis of the amino acid sequences of p58, p70, and p140 molecules revealed the existence of two cysteins proximal to the transmembrane region, only in the amino acid sequence of p140 molecules.