The challenging world of extracellular RNAs of helminth parasites

CUCHER, M.; ANCAROLA E; KAMENETZKY, L.

MOLECULAR IMMUNOLOGY

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2021

0161-5890

In the last years, cell free or extracellular RNAs (ex-RNAs) have emerged as novelintercellular messengers between animal cells, including pathogens. In infectiousdiseases, ex-RNAs represent novel players in the host-pathogen and pathogenpathogeninterplays and have been described in parasitic helminths from the threemajor taxonomic groups: nematodes, trematodes and cestodes. Altogether, it isestimated that approximately 30 percent of the world´s population is infected withhelminths, which cause debilitating diseases and syndromes.Ex-RNAs are protected from degradation by encapsulation in extracellular vesicles(EV), or association to proteins or lipoproteins, and have been detected in theexcretion/secretion products of helminth parasites, with EV as the preferredextracellular compartment under study. EV is the generic term used to describe aheterogenous group of subcellular membrane-bound particles, with varying sizes,biogenesis, density and composition. However, recent data suggests that this is not theonly means used by helminth parasites to secrete RNAs since ex-RNAs can also befound in EV-depleted samples. Furthermore, the use of pathogen ex-RNAs asbiomarkers promise the advent of new diagnostic tools though this field is still in earlystages of exploration.In this review, we summarize current knowledge of vesicular and non-vesicular ex-RNAs secretion in helminth parasites, their potential as biomarkers and the evidence oftheir role in parasite and host reciprocal communication, together with unansweredquestions in the field.