Extracellular Vesicles in Innate Immune Cell Programming

Abstract

Extracellular vesicles (EV) are a heterogeneous group of bilipid-enclosed envelopes that carry proteins, metabolites, RNA, DNA and lipids from their parent cell of origin. They mediate cellular communication to other cells in local tissue microenvironments and across organ systems. EV size, number and their biologically active cargo are often altered in response to pathological processes, including infection, cancer, cardiovascular diseases and in response to metabolic perturbations such as obesity and diabetes, which also have a strong inflammatory component. Here, we discuss the broad repertoire of EV produced by neutrophils, monocytes, macrophages, their precursor hematopoietic stem cells and discuss their effects on the innate immune system. We seek to understand the immunomodulatory properties of EV in cellular programming, which impacts innate immune cell differentiation and function. We further explore the possibilities of using EV as immune targeting vectors, for the modulation of the innate immune response, e.g., for tissue preservation during sterile injury such as myocardial infarction or to promote tissue resolution of inflammation and potentially tissue regeneration and repair.

Keywords: exosomes; hematopoietic stem cell; monocyte; neutrophil; transcription.

Figure 1

The crosstalk between innate immune cells through the generation and release of extracellular vesicles. The known (solid lines) and proposed (dotted lines) role of extracellular vesicles in the modulation of neutrophils, monocytes and macrophages and their pre-cursor hematopoietic stem cells (HSCs).

Figure 2

The crosstalk between neutrophils, monocytes and macrophages through the generation and release of extracellular vesicles (EV). Neutrophil derived microvesicles (NVDMs). Myeloperoxidase (MPO).

Figure 3

The crosstalk between monocytes and macrophages through the generation and release of extracellular vesicles (EV).