In vitro hatching of Trichuris suis eggs

Abstract

Eggs of the pig whipworm, Trichuris suis ova (TSO), are currently tested in human clinical trials for their potential immunomodulatory capacity. The biological potency of TSO (egg viability and infectivity) is traditionally assessed in Göttingen minipigs as the establishment of intestinal larvae after inoculation with a known number of eggs. To minimize testing in animal models, development of an in vitro egg hatching assay is proposed as a reliable, cost-effective, and a faster alternative to test the egg viability. The present study aimed to investigate the influence of different chemical, physical, and biological factors on egg hatching. Thus, in a series of experiments and in different combinations, the eggs were stimulated with glass beads, artificial gastric juice, bile salt and trypsin solution, fermentation gut medium, or stimulated with mucosal scrapings from the ileum and the large intestine of the infected and uninfected Göttingen minipig. Mechanical stimulation with glass beads presented a simple and reproducible method for egg hatching. However, incubation of eggs with mucosal scrapings from the ileum, caecum, and colon for 24 h at 38 °C significantly increased hatching.

Human Trichuriasis: Whipworm Genetics, Phylogeny, Transmission and Future Research Directions

“…One poorly understood mechanism in Trichuris development is that of host stimulusinduced egg hatching during passage though the small intestine. This has been shown to be highly host-parasite specific as Trichuris suis eggs require different stimuli to Trichuris muris for hatching [67][68][69]. Other mechanisms relate to larval establishment and evasion of host-immune responses, which are better understood today due to the Trichuris suis and Trichuris muris genome and transcriptome data [57••, 58••].…”

A method for collecting eggs of Pseudocapillaria tomentosa (Nematoda: Capillariidae) from zebrafish Danio rerio and efficacy of heat and chlorine for killing the nematode's eggs

“…Among several stimulation methods used to promote the egg hatching of T. suis , mechanical stimulation with glass beads was the most also effective (Vejzagic et al . ). Microwave irradiation has been reported to stimulate the growth of Caenorhabditis elegans L 1 larvae (Pomerai et al .…”

“…Two alternatives remain unexplained and deserve future evaluation: the first is that possibly the chlorine treatment provoked a shock on the eggs similar to that found when eggs were stimulated with glass beads (Vejzagic et al . ) and the second one is that the low chlorine concentration could have improved the water quality in the microenvironment of the slides.…”

“…Microwave irradiation has been reported to stimulate the growth of Caenorhabditis elegans L 1 larvae (Pomerai et al 2002). Two alternatives remain unexplained and deserve future evaluation: the first is that possibly the chlorine treatment provoked a shock on the eggs similar to that found when eggs were stimulated with glass beads (Vejzagic et al 2015) and the second one is that the low chlorine concentration could have improved the water quality in the microenvironment of the slides. Certain recommendations can be put forth from our study regarding practical applications for control of the infection in zebrafish colonies.…”

Reciprocal Interactions between Nematodes and Their Microbial Environments

“…Interestingly, bacteria-induced T. muris egg hatching seems to occur efficiently with members of Proteobacteria ( E. coli ) and Firmicutes ( Enterococcus caccae, Streptococcus hyointestinalis, Lactobacillus reuteri , and Lactobacillus amylovorus ). It is possible that many different bacterial species contribute via different mechanisms for optimal T. muris egg hatching (Vejzagić et al, 2015). …”