HISTOLOGY AND HISTOPATHOLOGY

From Cell Biology to Tissue Engineering

 

Review

Rab GTPases in the differential processing of phagocytosed pathogens versus efferocytosed apoptotic cells

Nima Taefehshokr1, Charles Yin1 and Bryan Heit1,2

1Department of Microbiology and Immunology, Center for Human Immunology, The University of Western Ontario and 2Associate Scientist, Robarts Research Institute, London, Ontario, Canada


Offprint requests to: Bryan Heit, Department of Microbiology and Immunology, Center for Human Immunology, The University of Western Ontario, London, Ontario, Canada. e-mail: bheit@uwo.ca


Summary. Phagocytosis is an important feature of innate immunity in which invading microorganisms are engulfed, killed and degraded and in some immune cells, their antigens presented to adaptive immune system. A closely related process, efferocytosis, removes apoptotic cells, and is essential for the maintenance of homeostasis. Both phagocytosis and efferocytosis are tightly regulated processes that involve target recognition and uptake through specific receptors, followed by endolysosomal trafficking and processing of the internalized target. Central to the uptake and trafficking of these targets are the Rab family of small GTPases, which coordinate the engulfment and trafficking of both phagocytosed and efferocytosed materials through the endolysosomal system. Because of this regulatory function, Rab GTPases are often targeted by pathogens to escape phagocytosis. In this review, we will discuss the shared and differential roles of Rab GTPases in phagocytosis and efferocytosis. Histol. Histopathol.

Key words: Phagocytosis, Efferocytosis, Rab GTPase, Phagosome, Efferosome

DOI: 10.14670/HH-18-252