Omics: Applications related to diagnosis, treatment, prevention and control of parasitic diseases. Part II. Helminths

Abstract

Schistosoma spp.Host-parasite interaction: One mystery concerning the intra-mammalian life of Schistosoma adults is its adaptation to the anaerobic glucose metabolism and lactate production. This was explained lately by the presence of Schistosoma aquaporins that are membrane-bound proteins for water transport. Aquaporins capability to transport lactate across the cell membrane was also elucidated thus solving the mystery in Schistosoma adaptation and survival [2] . Identification of novel diagnostic biomarkers:Several micro RNA (miRNA) types were isolated from sera of patients with schistosomiasis, e.g. miR-124-3p, Bantam miRNA, miR-2C-3p, miR-3488 and miR2a-5p. Since miRNAs are secreted from Schistosoma extracellular vesicles, they are considered diagnostic biomarkers for diagnosis and therapeutic monitoring [3,4] . In 2022, advances in bioinformatics held a revolution in the diagnosis of schistosomiasis. Genomic datasets of S. haematobium and S. japonicum allowed the investigators to compare between both genomes utilizing gene ontology. Notably, the latter is a bioinformatics approach unifying genetic representation across a species followed by further in silico identification of identical proteins. Accordingly, distinct S. japonicum genes were demonstrated and enlisted as potential diagnostic markers for infection by Asian schistosomiasis [5] . Additionally, a study carried out in Nigeria demonstrated the role of bioinformatics in the design of S. haematobium diagnostic kit depending on in silico determination of high immunogenic Schistosoma proteins [6] . Identification of drug targets and vaccine candidates:Based on advances in schistosome genomics, a family of promising schistosome vaccine antigens were suggested. The best vaccine candidates identified against schistosomiasis are protein molecules expressed on the tegument surface or secreted by schistosomula such as Sm29, and Sm-p80 that attracted much attention. Notably, Sm29 is a glycosyl-phosphatidyl inositol (GPI)anchored protein on Schistosoma tegument and the recombinant Sm29 vaccine exhibited Th1 immunity induction, and ~50% pathology reduction [7] . Besides, Sm-p80 is a subunit of the tegument cysteine protease, calpain that plays a crucial role in immune evasion. The recombinant Sm-p80 proved to be a promising vaccine candidate that achieved 80% improvement in liver pathology and a prominent Th1 response [8] . In addition to its role as a druggable molecule, investigating acetylcholinesterase (AChE) as a vaccine candidate against schistosomiasis was elucidated by omics and bioinformatics. Accordingly, two isoforms of AChE were identified in S. mansoni. The first was incorporated in the muscle layer to interact with heparin, i.e., a drug target. The other was GPIanchored to the surface membrane, i.e., a potential vaccine candidate [9] .