Pathogens and Their Effect on Exosome Biogenesis and Composition

Abstract

Exosomes are nanosized membrane microvesicles (30⁻100 nm) that have the capability to communicate intercellularly and transport cell components (i.e., miRNA, mRNA, proteins and DNA). Exosomes are found in nearly every cell type (i.e., mast cells, dendritic, tumor, and macrophages). There have been many studies that have shown the importance of exosome function as well as their unique packaging and targeting abilities. These characteristics make exosomes ideal candidates to act as biomarkers and therapeutics for disease. We will discuss the biogenesis, composition, and relationship of exosomes with non-viral microbial infections including gram-negative bacteria, gram-positive bacteria, Leishmania and Trypanosoma cruzi.

Keywords: Trypanosoma cruzi; bacteria; biomarker; exosomes; leishmaniasis.

Figure 1

Composition of mammalian-derived exosomes. Proteomic, Biochemical, and Immunological investigations have identified many specific proteins and RNAs present in some exosomes. This is a limited representation of common molecules present within some mammalian-derived exosomes. Molecules illustrated here are grouped based on category function or protein class: Tetraspanins, Enzymes, Cytoskeletal proteins, Heat Shock proteins/chaperone proteins, Membrane trafficking proteins, Immunoregulator molecules, Lipid rafts, MVB biogenesis proteins, and RNAs. Some of these molecules are also found in bacteria derived-exosomes (Figure 2) and protozoan derived-exosomes (Figure 3).

Figure 2

Composition of bacteria-derived exosomes. Proteomic, Biochemical, and Immunological investigations have identified many specific proteins and RNAs present in some exosomes. This is a limited representation of common molecules present within some bacteria-derived exosomes. Molecules illustrated here are grouped based on category function or protein class: Tetraspanins, Surface markers, Immunoregulator molecules, Mycobacteria proteins, Mycobacteria lipids, Toxins or virulence factors, DNA encoding genes, and RNAs. Some of these molecules are also found in protozoan derived-exosomes (Figure 3) and mammalian derived-exosomes (Figure 1).

Figure 3

Composition of protozoa-derived exosomes. Proteomic, Biochemical, and Immunological investigations have identified many specific proteins and RNAs present in some exosomes. This is a limited representation of common molecules present within some protozoa-derived exosomes. Molecules illustrated here are grouped based on category function or protein class: Chaperone proteins, Cytoskeletal proteins, Toxins or virulence factors, MVB biogenesis proteins, and RNAs. Some of these molecules are also found in bacteria derived-exosomes (Figure 2) and mammalian derived-exosomes (Figure 1).