Evaluation of Toxocara canis Glycosylated TES Produced in Pichia pastoris for Immunodiagnosis of Human Toxocariasis

Abstract

Recombinant proteins are a suggested alternative for the diagnosis of toxocariasis. The current Escherichia coli recombinant protein overexpression system usually produces insoluble products. As an alternative, yeast such as Pichia pastoris have secretory mechanisms, which could diminish the cost and time for production. This study aimed to produce recombinant proteins in Pichia pastoris and verify their sensibility and specificity in an indirect ELISA assay. Two sequences (rTES-30 and rTES-120) of Toxocara canis excretory-secretory antigens were cloned in a pPICZαB vector and expressed in P. pastoris KM71H. Sera samples collected from human adults infected by Toxocara spp. were tested by indirect ELISA using rTES-30 and rTES-120 as antigens. Recombinant proteins were detected at 72 hours after induction, in the HIGHLIGHTS  Pichia pastoris rTES evaluated as an alternative tool for toxocariasis diagnosis.  No difference between sensitivities of glycosylated and partial glycosylated rTES.  High-throughput expression and in vivo purification of rTES in Pichia pastoris. 2 Santos, L.M.; et al.

Human Toxocariasis: 2010 to 2020 Contributions from Brazilian Researchers

“…Roldán et al 71 showed that IgM antibodies used for the serodiagnosis of human toxocariasis showed low specificity, and Santos et al 72 found that Toxocara recombinant antigens developed with the use of the yeast Pichia pastoris instead of Escherichia coli showed low sensitivity for the immunodiagnosis of Toxocara infections. On the other hand, when Santos et al 73 previously used recombinant antigens of low molecular weight (30 kDa), they obtained better results, especially in surveys that included children.…”

“…In an attempt to improve the sensitivity and specificity of immunological tests for the diagnosis of human toxocariasis, several researchers sought to identify possible markers of infections and the immunodominant antigens of T. canis. 64,[66][67][68][69][70] Roldán et al 71 showed that IgM antibodies used for the serodiagnosis of human toxocariasis showed low specificity, and Santos et al 72 found that Toxocara recombinant antigens developed with the use of the yeast Pichia pastoris instead of Escherichia coli showed low sensitivity for the immunodiagnosis of Toxocara infections. On the other hand, when Santos et al 73 previously used recombinant antigens of low molecular weight (30 kDa), they obtained better results, especially in surveys that included children.…”