Byrd Andreina, Hoffmann Sabrina C, Jarahian Mostafa, Momburg Frank, Watzl Carsten
Institute for Immunology, University Heidelberg, Heidelberg, Germany.
PLoS One. 2007 Dec 19;2(12):e1339. doi: 10.1371/journal.pone.0001339.
The natural cytotoxicity receptors (NCR) are important to stimulate the activity of Natural Killer (NK) cells against transformed cells. Identification of NCR ligands and their level of expression on normal and neoplastic cells has important implications for the rational design of immunotherapy strategies for cancer.
METHODOLOGY/PRINCIPAL FINDINGS: Here we analyze the expression of NKp30 ligand and NKp44 ligand on 30 transformed or non-transformed cell lines of different origin. We find intracellular and surface expression of these two ligands on almost all cell lines tested. Expression of NKp30 and NKp44 ligands was variable and did not correlate with the origin of the cell line. Expression of NKp30 and NKp44 ligand correlated with NKp30 and NKp44-mediated NK cell lysis of tumor cells, respectively. The surface expression of NKp30 ligand and NKp44 ligand was sensitive to trypsin treatment and was reduced in cells arrested in G(2)/M phase.
CONCLUSION/SIGNIFICANCE: These data demonstrate the ubiquitous expression of the ligands for NKp30 and NKp44 and give an important insight into the regulation of these ligands.
自然细胞毒性受体（NCR）对于刺激自然杀伤（NK）细胞针对转化细胞的活性很重要。鉴定NCR配体及其在正常细胞和肿瘤细胞上的表达水平对于合理设计癌症免疫治疗策略具有重要意义。
方法/主要发现：在此，我们分析了NKp30配体和NKp44配体在30种不同来源的转化或未转化细胞系上的表达。我们发现在几乎所有测试的细胞系上这两种配体均有细胞内和表面表达。NKp30和NKp44配体的表达是可变的，并且与细胞系的来源无关。NKp30和NKp44配体的表达分别与NKp30和NKp44介导的NK细胞对肿瘤细胞的杀伤作用相关。NKp30配体和NKp44配体的表面表达对胰蛋白酶处理敏感，并且在停滞于G(2)/M期的细胞中表达降低。
结论/意义：这些数据证明了NKp30和NKp44配体的普遍表达，并为这些配体的调控提供了重要见解。
