Development of a diagnostic test for Entamoeba histolytica using idiotype expression in human

Generation of internal image monoclonal anti-idiotypic antibodies against idiotypic antibodies to GP5 antigen of porcine reproductive and respiratory syndrome virus

Syngeneic monoclonal anti-idiotypic antibodies (Mab2s) were generated against idiotypic antibodies to membrane glycoprotein GP5 of porcine reproductive and respiratory syndrome virus (PRRSV) using the sequential immunization method. Six of 12 Mab2s possessed potential internal image characteristics by recognizing a common idiotype on murine and swine anti-GP5 antibodies. Further serological characterization demonstrated that one of the Mab2 (Mab2-5G2) represents internal image anti-idiotope which mimicked the GP5 antigen that inhibited the interaction between idiotypic anti-GP5 antibodies and GP5 antigen, its reaction with the idiotypic anti-GP5 antibody was inhibited by GP5 antigen and detected the common Id on anti-PRRSV antibodies from pigs that were experimentally infected with PRRSV. In addition, Mab2-5G2 identified a soluble protein on MA-104 and porcine alveolar macrophages. These results indicate that Mab2-5G2 may be a useful candidate as an alternative PRRSV serodiagnostic reagent and a useful probe to study PRRSV-cell interaction.

Involvement of protein kinases on the process of erythrophagocytis by Entamoeba histolytica

Erythrophagocytic capacity of trophozoites of Entamoeba histolytica is considered a factor in the virulence of this pathogenic protozoan. We present evidence showing that such activity resembles the ingestion of microorganisms by highly differentiated phagocytic cells, such as macrophages. Previous treatment of the trophozoites with genistein or tyrphostin, inhibitors of tyrosine protein kinases, with staurosporine, a protein kinase C inhibitor, and wortmannin, a fungal metabolite that inhibits phosphoinositide 3-OH kinase, significantly inhibited their erythrophagocytic capacity.