Effects of crude antigen and excretory-secretory products of Clonorchis sinensis on T cells / 中国人兽共患病学报

We investigated the roles of the crude antigen(CA) of Clonorchis sinensis and excretory secretory products (ESPs) in the polarization of Th1 and Th2 cells.Bone marrow-derived cells were generated from BALB/c mice and isolated into immature DCs;immature DCs were then treated with either CA (CA stimulated group),ESPs (ESPs stimulated group),LPS (positive control group) or PBS (negative control group) for 24 hours.Then the CD4+T cells were isolated from mouse spleen by using anti mouse-CD4 Microbeads,and further cocultured with stimulated DCs for another 72 hours.The purities of DCs and CD4+ T cells were evaluated by flow cytometry and the expressing levels of T-bet mRNA and GATA-3 mRNA were detected by real-time PCR.ELISA was used to detect the levels of IFN-γ and IL-4 cytokines in the supernatant.mRNA levels of T-bet and GATA-3 in the ESPs group were higher than those in PBS-stimulated group (P＜0.05).The concentrations of IFN-γ and IL-4 cytokines in the culture were increased in the ESPs group,compared with PBS stimulated group(P＜0.05).IFN-γ but not IL-4 was increased in CA group (P＜0.05).The results implied that CA might play a role in Th1 type immune response,and ESPs likely play roles in both Th1 and Th2 immune responses.

Cross-reactivity of Toxocariasis with Crude Antigen of Toxascaris leonina Larvae by ELISA

Roundworms of Toxocara canis and Toxascaris leonina are common gastrointestinal helminths of canids over the world. Humans are infected with T. canis larvae through ingestion of infective eggs in contaminated environments or larvae by consumption of raw or uncooked meat or livers. Recently, patients of clinically diagnosed toxocariasis are increasing and require correct diagnosis in Korea. The present study investigated serological cross-reactivity between crude antigens of T. canis (TCLA) and T. leonina (TLLA) larvae. We collected serum specimens from 177 toxocariasis patients who were clinically suspected in the Seoul National University Hospital and 115 healthy controls. An ELISA method for toxocariasis was used to evaluate diagnostic efficacy of TLLA for serodiagnosis of human toxocariasis. The IgG ELISA using TLLA gave 14 (14.3%) positives of 98 TCLA positive specimens among 177 suspected toxocariasis patients. Most of them showed high absorbances with TCLA. In conclusion, there is a partial cross reaction between serum specimens of toxocariasis and TLLA.

Significance of Serum Antibody Test for Toxocariasis in Healthy Healthcare Examinees with Eosinophilia in Seoul and Gyeongsangnam-do, Korea

There have been numerous reports on the relationship between eosinophilia and toxocariasis. The present study investigated seropositive rates of toxocariasis among healthy people with or without eosinophilia in urban and rural areas, and assessed risk factors for positive antibody test. A total of 610 healthy people, who visited health check-up (Medicheck(R), Korea Association of Health Promotion), 310 from Seoul and 300 from Gyeongsangnam-do, were subjected for this study. Their serum samples were tested by ELISA with the crude antigen of Toxocara canis larvae. Cross-reactions with other tissue invading helminth antigens were also investigated. Total antibody positive rate of toxocariasis was 8.7% of the 610 subjects. When the subjects were grouped into 3 by their eosinophil counts, the antibody positive rates significantly differed by the groups; 5.9% (18/306) in the group500/microL (P=0.028). A total of 22 serum samples cross-reacted with other tissue-invading helminth antigens. A questionnaire analysis recognized drinking alcohol and smoking as significant risk factors of toxocariasis. In conclusion, toxocariasis antibody positive rate is correlated with eosinophil counts. It is recommended that healthy subjects with eosinophilia by routine health examination and risk factors undergo Toxocara serology by multiantigen ELISA to investigate etiology.

Serodiagnosis of Toxocariasis by ELISA Using Crude Antigen of Toxocara canis Larvae

Toxocariasis is a worldwide zoonosis caused by larvae of ascarid nematodes of dogs or cats, Toxocara canis or T. cati. Diagnosis of human toxocariasis currently relies on serology that uses T. canis excretory-secretory antigen to detect specific IgG antibodies by ELISA. We investigated the serodiagnostic efficacy of ELISA using crude antigen of T. canis larvae (TCLA). Serum specimens of 64 clinically confirmed toxocariasis, 115 healthy controls, and 119 other tissue-invading helminthiases were screened by ELISA using TCLA. The ELISA using TCLA showed 92.2% (59/64 patient samples) sensitivity and 86.6% (103/119) specificity. Its positive diagnostic predictivity was 78.7% and negative predictivity was 97.8%. No serum of healthy controls reacted but that of anisakiasis (45.5%), gnathostomiasis (19.2%), clonorchiasis (15.8%), sparganosis (11.1%), and cysticercosis (6.3%) cross-reacted. Immunoblot analysis on TCLA recognized antigenic proteins of 28- and 30-kDa bands in their dominant protein quantity and strong blotting reactivity. The present results indicate that the ELISA using our TCLA antigen is acceptable by the sensitivity and specificity for serodiagnosis of human toxocariasis. ELISA with TCLA is recommended to make differential diagnosis for patients with any sign of organ infiltration and eosinophilia.

Recognition of Specific Antigens by Specific IgG and IgE During Anaphylactic Shock Induced by Echinococcus granulosus in Sheep / 中国寄生虫学与寄生虫病杂志

Objective To determine the specific recognition of Echinococcus granulosus (E.g.) cyst fluid crude antigen (EgCF) and antigen B (EgB) by serum specific IgG and IgE using Western blotting during anaphylactic shock induced by E. g. in sheep, and to investigate the importance of defined characteristics and molecular weight of the specific antigens. Methods EgCF was obtained through local slaughterhouses in Urumqi from the cysts of infected sheep liver. Western blotting was used to analyze total specific IgG and IgE antibodies in serum from sheep infected with E.g. using either crude antigen of E. g. and EgB, and to understand specific recognition of hydatid cyst antigens by serum total IgG and specific IgE. Results SDS-PAGE and Western blotting showed that there were differences between EgB and EgCF in electrophoresis pattern. EgB was recognized by IgG from sera of infected sheep in a series of bands with molecular weight ranging from 31, 43 to 66.2 kDa. No binding of IgG against EgCF was observed in any serum from the infected sheep during anaphylactic shock. In contrast, specific IgE antibodies in E. g. infected sheep obviously recognized the single 43 kDa subunit of EgCF, but no binding of specific IgE against EgB was observed in sera of the infected sheep. Conclusion EgCF is consisted of antigenic components in which there is a specific antigen against IgE with a molecular weight of over 43 kDa. This component may lead to an anaphylactic shock induced by E. g. . EgB is a specific antigen against the total IgG but not to the specific IgE.