de Sanctis J B, Blanca I, Radzioch D, Bianco N E
Institute of Immunology, Faculty of Medicine, Central University of Venezuela, Caracas.
Immunology. 1994 Oct;83(2):232-9.
Lipoprotein lipase (LPL) is the key enzyme in the metabolism of triglyceride-rich lipoproteins. The patterns of LPL mRNA expression and secretion of the enzyme have not yet been established in natural killer (NK) cells. We show in the present communication that CD3- CD16+ cells (NK cells) transcribe LPL mRNA, express LPL on the surface and secrete the enzyme. In contrast, there is no LPL expression on the surface of highly purified B and T lymphocytes. Stimulation of NK cells with interleukin-2 (IL-2) reduced the expression of LPL on their surface and augmented the secretion of LPL by the cells. The addition of anti-LPL antibodies to NK cells in culture led to a complete abrogation of cytotoxicity of NK cells against the K562 tumour cell line. Furthermore, IL-2 stimulation of effector cells reversed the anti-LPL antibody-induced inhibition of cytotoxic activity. Overall, these findings suggest that LPL plays a key role in the cytotoxic activity of NK cells.
脂蛋白脂肪酶（LPL）是富含甘油三酯脂蛋白代谢中的关键酶。自然杀伤（NK）细胞中LPL mRNA的表达模式和该酶的分泌情况尚未明确。我们在本报告中表明，CD3 - CD16 +细胞（NK细胞）转录LPL mRNA，在表面表达LPL并分泌该酶。相比之下，高度纯化的B淋巴细胞和T淋巴细胞表面没有LPL表达。用白细胞介素-2（IL-2）刺激NK细胞会降低其表面LPL的表达，并增加细胞分泌LPL。在培养的NK细胞中加入抗LPL抗体导致NK细胞对K562肿瘤细胞系的细胞毒性完全消除。此外，IL-2刺激效应细胞可逆转抗LPL抗体诱导的细胞毒性活性抑制。总体而言，这些发现表明LPL在NK细胞的细胞毒性活性中起关键作用。
