Antigen (Ag)-presenting cells capture or synthesize Ags that are processed into peptides bound and displayed on the plasma membrane by major histocompatibility complex (MHC) molecules. Here, we review a mechanism that enables cells to present Ag-loaded MHC molecules that they have not produced themselves, namely trogocytosis. During trogocytosis, a cell acquires fragments from another living cell without, in most cases, affecting the viability of the donor cell. The trogocytic cell can incorporate into its own plasma membrane (becoming cross-dressed) proteins acquired from the donor cell, including intact Ag and MHC molecules. Trogocytosis and cross-dressing expand the immunological functions that immune and nonimmune cells are able to carry out, with both beneficial and deleterious consequences.

抗原 (Ag) 呈递细胞捕获或合成 Ag，这些 Ag 被加工成肽，通过主要组织相容性复合体 (MHC) 分子结合并展示在质膜上。在这里，我们回顾了一种使细胞能够呈现它们自身未产生的负载 Ag 的 MHC 分子的机制，即trogocytosis。在吞噬过程中，一个细胞从另一个活细胞获取碎片，在大多数情况下，不会影响供体细胞的活力。盘形细胞可以将从供体细胞获得的蛋白质（包括完整的 Ag 和 MHC 分子）整合到自己的质膜中（变得异装）。吞噬作用和异装扩大了免疫和非免疫细胞能够执行的免疫功能，带来有益和有害的后果。