Editorial: Insights into glyco-parasitology

Abstract

Editorial on the Research Topic Insights into glyco-parasitology "Glycoscience" and "Parasitology" are complex, long-studied fields of science, with enormous efforts focused on both scientific areas. The combination of "Glyco-parasitology" brings together the important and unique features of glycans related to parasites, parasite biology and immune functions, with many questions still unexplored. This is partially because life cycles, generation of glycans, and functions of glyco-related molecules of parasites and hosts themselves are complicated and yet to be fully defined. For example, expression of glycoforms (glycan structures) differ among each life stage of a parasite and susceptibilities to parasitic infection differ among the strains or individuals in the host species. These features may create difficulties in merging Glycoscience and Parasitology, but there are cutting-edge studies happening across the world and we have brought together a collection of them for this Research Topic, "Insights into Glyco-parasitology".It is not a stretch to say that parasitic infections are mediated by glyco-related molecules. Many of the parasites utilize their glyco-binding molecules, some of which may be glycosylphosphatidylinositol (GPI)-anchored, to attach to and infect hosts (Loukas and Maizels, 2000;Petri et al., 2002; Harcus et al., 2009). Some transfer host glycans to themselves to evade the host's immune responses (Campetella et al., 2020). In some cases, glycan-glycan interactions are important to determine and drive parasite-host interactions (Hall et al., 2020). On the host side, many glycans and glyco-related molecules of parasites are antigenic to humans, and cause or modulate an immune response. In this Research Topic, Prasanphanich et al. showed that IgG antibodies, generated during infection, targeted Schistosoma mansoni complex-type N-glycans with core α2-xylose and core α3-fucose. These antibodies could kill schistosomula in a complement-dependent manner. From the results, we can see an exciting possibility for vaccine development targeting the core xylose/core fucose glycans, and such vaccines are not yet available towards S. mansoni (Bunte et al., 2022). Some immune cells attach to and phagocytose the parasites via glycan interactions, and thereby, the parasites are able to infect and proliferate in the immune cells (Tanaka et al., 2007;Lefèvre et al., 2013). Membranous surfaces are covered by mucous consisting mainly of mucins and other glycoproteins, which are used for maintaining the humidity of the body, protecting from physical damage, retaining beneficial microorganisms and preventing virulent microorganisms from entering (Garić et al., 2020;Paone and Cani, 2020). Mucins are components of tears, saliva and the mucous layers covering digestive and