Deciphering the glycogenome of schistosomes

Abstract

Schistosoma mansoni and other Schistosoma sp. are multicellular parasitic helminths (worms) that infect humans and mammals worldwide. Infection by these parasites, which results in developmental maturation and sexual differentiation of the worms over a period of 5–6 weeks, induces antibodies to glycan antigens expressed in surface and secreted glycoproteins and glycolipids. There is growing interest in defining these unusual parasite-synthesized glycan antigens and using them to understand immune responses, their roles in immunomodulation, and in using glycan antigens as potential vaccine targets. A key problem in this area, however, has been the lack of information about the enzymes involved in elaborating the complex repertoire of glycans represented by the schistosome glycome. Recent availability of the nuclear genome sequences for Schistosoma sp. has created the opportunity to define the glycogenome, which represents the specific genes and cognate enzymes that generate the glycome. Here we describe the current state of information in regard to the schistosome glycogenome and glycome and highlight the important classes of glycans and glycogenes that may be important in their generation.

Comprehensive Transcriptome Analysis of Sex-Biased Expressed Genes Reveals Discrete Biological and Physiological Features of Male and Female Schistosoma japonicum

“…Glycosylation in schistosomes is a complex process which plays an essential role in host-pathogen interplay, particularly in terms of immune evasion and modulation [ 82 ]. A comprehensive glycomic analysis has revealed that the dominant N-glycans structure dynamically changes during the development of S mansoni .…”

Xylose donor transport is critical for fungal virulence

“…The double mutant population increased very slowly in both A/JCr and C57BL/6 mice, likely due to its slower growth rate under stress ( Fig 6C , S4 Fig ) and reduced ability to resist host defenses ( Fig 6A and 6B ). Xyl modifications have been identified as immunodominant epitopes in antibody responses to allergens and pathogens [ 39 , 40 ], and the absence of Xyl modifications in uxt1 Δ uxt2 Δ did increase immune detection and clearance of the pathogen in vitro ( Fig 6A and 6B ). The mutant also remained confined to the lungs of A/JCr mice ( S7 Fig ) and was slow to cause lethal meningoencephalitis in C57BL/6 mice ( S6 Fig ).…”

Metazoan Parasite Vaccines: Present Status and Future Prospects

“…It has also been indicated that tick-derived carbohydrates (such as alpha fucosylation of tick glycoproteins by fucosyltransferases) are role-players in tick-pathogen interactions, such as colonization and transmission in vector cells (e.g., Anaplasma phagocytophilum ) (de La Fuente et al, 2006 ; Pedra et al, 2010 ; Cabezas-Cruz et al, 2017 ). Similar studies in schistosomes have indicated an important role of glycan epitopes in host-parasite interactions including modulation and evasion of host innate and adaptive immunity, as well as infection biology during snail-schistosome interactions (e.g., fucosylated structures produced on larval surfaces and released during larval transformation and sporocyst development) (Mickum et al, 2014 ; Jurberg and Brindley, 2015 ; Smit et al, 2015 ; Nascimento Santos et al, 2017 ). Investigation of carbohydrate-protein interactions have been revolutionized with the development of functional glycomics tools such as glycan arrays that have been applied successfully in the analysis of glycan binding protein associated biology, host-pathogen interactions and immune recognition (by antigen specific antibodies) (Heimburg-Molinaro et al, 2011 ; Rillahan and Paulson, 2011 ; Arthur et al, 2014 ).…”