Prevalence of Toxoplasma gondii parasite in captive Mexican jaguars determined by recombinant surface antigens (SAG1) and dense granular antigens (GRA1 and GRA7) in ELISA-based serodiagnosis

et al. 2020

Preprint

Background: Toxoplasma gondii infection endangers human health and affects animal husbandry. Serological detection is the main method used for epidemiological investigations and diagnosis of toxoplasmosis. The key to effective diagnosis of toxoplasmosis is the use of a standardized antigen and a specific and sensitive detection method. Peroxiredoxin is an antigenic protein and vaccine candidate antigen of T. gondii that has not yet been exploited for diagnostic application. Methods: In this study, recombinant T. gondii peroxiredoxin protein (rTgPrx) was prepared and used in dot-immunogold-silver staining (Dot-IGSS) to detect IgG antibodies in serum from mice and pregnant women. The rTgPrx-Dot-IGSS method was established and optimized using mouse serum. Furthermore, serum samples from pregnant women were analyzed by rTgPrx-Dot-IGSS.Results: Forty serum samples from mice infected with T. gondii and twenty negative serum samples were analyzed. The sensitivity and specificity of rTgPrx-Dot-IGSS were 97.5% and 100%, respectively, equivalent to those of a commercial ELISA kit for anti-Toxoplasma IgG antibody. Furthermore, 540 serum samples from pregnant women were screened with a commercial ELISA kit. Eighty-three positive and 60 negative serum samples were analyzed by rTgPrx-Dot-IGSS. The positive rate was 95.18%, comparable to that obtained with the commercial ELISA kit.Conclusions: The Dot-IGSS method with rTgPrx as an antigen might be useful for diagnosing T. gondii infection in individuals.

Section: Discussionmentioning

confidence: 99%

Evaluation of toxoplasmosis in pregnant women using dot-immunogold-silver staining with recombinant Toxoplasma gondii peroxiredoxin protein

et al. 2020

Preprint

“…The results indicated a positive rate of 97.5% and no cross-reactivity. A previous study showed that the sensitivity and specificity of IgG ELISA with a single recombinant surface antigen (SAG1) or recombinant dense granular antigens (GRA1 and GRA7) in captive jaguars were 92.5 ~ 97.5% and 83.3 ~ 91.6%, respectively, and that the sensitivity and specificity were significantly increased when these antigens were mixed [ 30 ]. Therefore, the sensitivity of rTgPrx-Dot-IGSS could be increased by mixing rTgPrx with other specific antigens.…”

Section: Discussionmentioning

confidence: 99%

Evaluation of toxoplasmosis in pregnant women using dot-immunogold-silver staining with recombinant Toxoplasma gondii peroxiredoxin protein

et al. 2020

BMC Infect Dis

Background Toxoplasma gondii infection endangers human health and affects animal husbandry. Serological detection is the main method used for epidemiological investigations and diagnosis of toxoplasmosis. The key to effective diagnosis of toxoplasmosis is the use of a standardized antigen and a specific and sensitive detection method. Peroxiredoxin is an antigenic protein and vaccine candidate antigen of T. gondii that has not yet been exploited for diagnostic application. Methods In this study, recombinant T. gondii peroxiredoxin protein (rTgPrx) was prepared and used in dot-immunogold-silver staining (Dot-IGSS) to detect IgG antibodies in serum from mice and pregnant women. The rTgPrx-Dot-IGSS method was established and optimized using mouse serum. Furthermore, serum samples from pregnant women were analyzed by rTgPrx-Dot-IGSS. Results Forty serum samples from mice infected with T. gondii and twenty negative serum samples were analyzed. The sensitivity and specificity of rTgPrx-Dot-IGSS were 97.5 and 100%, respectively, equivalent to those of a commercial ELISA kit for anti-Toxoplasma IgG antibody. Furthermore, 540 serum samples from pregnant women were screened with a commercial ELISA kit. Eighty-three positive and 60 negative serum samples were analyzed by rTgPrx-Dot-IGSS. The positive rate was 95.18%, comparable to that obtained with the commercial ELISA kit. Conclusions The Dot-IGSS method with rTgPrx as an antigen might be useful for diagnosing T. gondii infection in individuals.

“…As molecular biology techniques have been developed, recombinant antigens have recently been used instead of natural antigens, such as surface antigens (SAG1), dense granular antigens (GRA1 and GRA7) and rhoptry antigens (ROP18), for diagnostic tests [27][28][29][30]. Mass and standardized production of recombinant antigens is straightforward [9].…”

Section: Discussionmentioning

confidence: 99%

“…The results indicated a positive rate of 97.5% and no cross-reactivity. A previous study showed that the sensitivity and specificity of IgG ELISA with a single recombinant surface antigen (SAG1) or recombinant dense granular antigens (GRA1 and GRA7) in captive jaguars were 92.5 ~ 97.5% and 83.3 ~ 91.6%, respectively, and that the sensitivity and specificity were significantly increased when these antigens were mixed [29]. Therefore, the sensitivity of rTgPrx-Dot-IGSS could be increased by mixing rTgPrx with other specific antigens.…”

Section: Discussionmentioning

confidence: 99%

Serodiagnosis of toxoplasmosis in pregnant women using dot-immunogold-silver staining with recombinant Toxoplasma gondii peroxiredoxin protein

et al. 2020

Preprint

Background Toxoplasma gondii infection endangers human health and affects animal husbandry. Serological detection is the main method used for epidemiological investigations and diagnosis of toxoplasmosis. The key to effective diagnosis of toxoplasmosis is the use of a standardized antigen and a specific and sensitive detection method. Peroxiredoxin is an antigenic protein and vaccine candidate antigen of T. gondii that has not yet been exploited for diagnostic application. Methods In this study, recombinant T. gondii peroxiredoxin protein (rTgPrx) was prepared and used in dot-immunogold-silver staining (Dot-IGSS) to detect IgG antibodies in serum from mice and pregnant women. The rTgPrx-Dot-IGSS method was established and optimized using mouse serum. Furthermore, serum samples from pregnant women were analyzed by rTgPrx-Dot-IGSS. Results Forty serum samples from mice infected with T. gondii and twenty negative serum samples were analyzed. The sensitivity and specificity of rTgPrx-Dot-IGSS were 97.5% and 100%, respectively, equivalent to those of a commercial ELISA kit for anti-Toxoplasma IgG antibody. Furthermore, 540 serum samples from pregnant women were screened with a commercial ELISA kit. Eighty-three positive and 60 negative serum samples were analyzed by rTgPrx-Dot-IGSS. The positive rate was 95.18%, comparable to that obtained with the commercial ELISA kit. Conclusions The Dot-IGSS method with rTgPrx as an antigen might be useful for diagnosing T. gondii infection in individuals.