Paidassi Helena, Tacnet-Delorme Pascale, Arlaud Gerard J, Frachet Philippe
Laboratoire d'Enzymologie Moléculaire, Institut de Biologie Structurale Jean-Pierre Ebel (UMR 5075), CEA, CNRS, Université Joseph Fourier, 41 rue J. Horowitz, F-38027 Grenoble, France.
Crit Rev Immunol. 2009;29(2):111-30. doi: 10.1615/critrevimmunol.v29.i2.20.
The uptake of apoptotic cells by macrophages and dendritic cells or nonprofessional phagocytes is crucial for development and tissue homeostasis. This is of special importance because deficiencies in the recognition or removal of apoptotic cells may result in autoimmune diseases. The efficient elimination of an apoptotic cell involves contact between the altered cell and the phagocyte, specific recognition, and phagocytosis of the target. These processes are closely associated with the release of anti-inflammatory cytokines and the induction of self-tolerance. This review focuses on the different types of signals, bridging molecules and receptors involved in both steps of the uptake process. Additionally, the role of soluble pattern recognition molecules from the innate immune system, known for a long time to discriminate pathogens from self and more recently to sense altered self, is discussed. This applies to complement Clq, which appears to sense multiple ligands exposed at the apoptotic cell surface, to be involved in their engulfment by phagocytes, and to modulate dendritic cell maturation.
巨噬细胞、树突状细胞或非专职吞噬细胞对凋亡细胞的摄取对于发育和组织稳态至关重要。这一点尤为重要，因为识别或清除凋亡细胞的缺陷可能导致自身免疫性疾病。有效清除凋亡细胞涉及改变的细胞与吞噬细胞之间的接触、特异性识别以及对靶标的吞噬作用。这些过程与抗炎细胞因子的释放和自身耐受的诱导密切相关。本综述重点关注摄取过程两个步骤中涉及的不同类型信号、衔接分子和受体。此外，还讨论了先天性免疫系统中可溶性模式识别分子的作用，这类分子长期以来用于区分病原体与自身，最近还用于感知改变的自身。这适用于补体C1q，它似乎能感知凋亡细胞表面暴露的多种配体，参与吞噬细胞对它们的吞噬，并调节树突状细胞的成熟。
