The cellular uptake, intracellular processing, and presentation of foreign antigen are crucial processes for eliciting an effective adaptive host response to the majority of pathogens. The effective recognition of antigen by T cells requires that it is first processed and then presented on MHC molecules that are expressed on other cells. A critical step leading to the presentation of antigen is delivering the foreign cargo to an intracellular compartment where the antigen can be processed and loaded onto MHC molecules. Fc-gamma receptors (FcγRs) recognize IgG-coated targets, such as opsonized pathogens or immune complexes (ICs). Cross-linking leads to internalization of the cargo with associated activation of down-stream signaling cascades. FcγRs vary in their affinity for IgG and intracellular trafficking, and therefore have an opportunity to regulate antigen presentation by controlling the shuttling and processing of their cargos. In this way, they critically influence physiological and pathophysiological adaptive immune cell functions. In this review, we will cover the contribution of FcγRs to antigen-presentation with a focus on the intracellular trafficking of IgG-ICs and the pathways that support this function. We will also discuss genetic evidence linking FcγR biology to immune cell activation and autoimmune processes as exemplified by systemic lupus erythematosus (SLE).

细胞摄取，细胞内加工和外源抗原的呈递是引发对大多数病原体有效的适应性宿主反应的关键过程。T细胞对抗原的有效识别需要先对其进行处理，然后再呈现在其他细胞上表达的MHC分子上。导致抗原呈递的关键步骤是将外来货物运送到细胞内区室，在那里可以加工抗原并将其加载到MHC分子上。Fc-γ受体（FcγR）识别IgG包被的靶标，例如调理病原体或免疫复合物（ICs）。交联导致货物的内部化以及下游信号级联的激活。FcγR对IgG和细胞内运输的亲和力有所不同，因此有机会通过控制货物的穿梭和加工来调节抗原呈递。以这种方式，它们严重影响生理和病理生理适应性免疫细胞功能。在这篇综述中，我们将介绍FcγR对抗原呈递的贡献，重点是IgG-ICs的细胞内运输以及支持该功能的途径。我们还将讨论遗传证据，将FcγR生物学与免疫细胞激活和自身免疫过程联系起来，例如系统性红斑狼疮（SLE）。我们将介绍FcγR对抗原呈递的贡献，重点是IgG-IC的细胞内运输以及支持该功能的途径。我们还将讨论遗传证据，将FcγR生物学与免疫细胞激活和自身免疫过程联系起来，例如系统性红斑狼疮（SLE）。我们将介绍FcγR对抗原呈递的贡献，重点是IgG-IC的细胞内运输以及支持该功能的途径。我们还将讨论遗传证据，将FcγR生物学与免疫细胞激活和自身免疫过程联系起来，例如系统性红斑狼疮（SLE）。