ICR株小鼠犬蛔蟲症體液性免疫及抗原交叉反應之研究

The ELISA method using Toxocara canis larval E/S (TcES) products, homogenized larval (TcLA) extracts and adult worm (TcAA) extracts, was used to evaluate the responses of IgE, IgM and IgG antibodies in sera from ICR strain mice inoculated with 250 T. canis embryonated eggs. Heterologous sera from mice infected with Ascaris suum or Angiostrongylus cantonensis were also included in the study, to assess the cross-reaction of T. canis antigens. Results revealed that homologous IgG and IgM antibodies against the TcES or TcLA antigen. could be detected at the second and the first week post infection, respectively. No cross-reaction of heterologous IgG or IgM antibody against the TcES antigen was observed. Except in the case of the IgM antibody from mice infected with A. cantonensis, neither T. canis nor A. suum IgM antibody reacted with the TcAA antigen. The subclasses of homologous IgG antibodies against the TcES antigen were mainly IgG2 and IgG3. In contrast, the subclasses of homologous IgG antibodies against the TcLA antigen were mainly IgG1 and IgG2. However, homologous and heterologous IgM and IgE antibodies reacted nonspecifically with TcES, TcLA or TcAA antigen thus were not satisfactory diagnostic antibodies for murine toxocariasis. Our results indicated that both TcES and TcLA antigens were excellent diagnostic antigens for murine toxocariasis by IgG-ELISA.