Rab22a: A novel regulator of immune functions

LUIS SEGUNDO MAYORGA; CEBRIAN, IGNACIO

MOLECULAR IMMUNOLOGY

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2018

0161-5890

Dendritic cells (DCs) trigger CD8 + T cell responses after the internalization of exogenous antigens in a process called cross-presentation. Multiple intracellular transport events within the endocytic and secretory routestake place in order to accomplish this fundamental immunological process. The endomembrane system can be envisioned as a complex network of membrane domains coordinately working in the fusion of organelles, thebudding of vesicles and tubules, and modifying the molecular composition of the limiting membranes. In this context of tightly regulated and dynamic endomembrane transport, small GTPases of the Rab family display apivotal role by organizing membrane microdomains and defining specific identities to the different intracellular compartments. In this review, we synthesize and update the current knowledge about Rab22a, which has beeninvolved in several immune functions. In this way, we analyze the intracellular localization of Rab22a and its important role in the endocytic recycling, including its relevance during MHC-I trafficking, antigen crosspresentationby DCs and the formation of T cell conjugates. We also describe how different pathogenic microorganisms hijack Rab22a functions to achieve efficient infection and intracellular survival strategies. Furthermore,we examine the oncogenic properties of Rab22a and how its expression determines the progression of many tumors. In summary, we highlight the role of Rab22a as a key effector of the intracellular trafficking that could beexploited in future therapies to modulate the immune system.