VIEW ARTICLE

Techniques

Production of Monoclonal Antibodies Against a Mycoplasmalike Organism Associated with Sweetpotato Witches’ Broom. W. C. Shen, Former graduate student, Department of Plant Pathology and Entomology, National Taiwan University, Taipei, Taiwan 10764, R. O. C., Present address: Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan 40227, R. O. C.; C. P. Lin, professor, Department of Plant Pathology and Entomology, National Taiwan University, Taipei, Taiwan 10764, R. O. C. Phytopathology 83:671-675. Accepted for publication 17 February 1993. Copyright 1993 The American Phytopathological Society. DOI: 10.1094/Phyto-83-671.

Five stable hybridoma clones secreting specific monoclonal antibodies against the sweetpotato witches’ broom (SPWB)-mycoplasmalike organism (MLO) were produced by employing an immunization scheme for the induction of the immunological tolerance of mice to plant antigens prior to the administration of MLO immunogens. Neonatal BALB/c mice were injected first with nontarget plant antigens present in an immunogen preparation and were immunized with MLO-enriched antigens prepared by Percoll density-gradient fractionation or by enzyme treatments 6 wk later. With these monoclonal antibodies, SPWB-MLO in diseased sweetpotato and periwinkle was specifically identified by indirect enzyme-linked immunosorbent assay (ELISA) and by immunofluorescent staining. Antibody titers for hybridoma-culture supernatants (measured by indirect ELISA) ranged from 320 to 5,120 for SPWB-MLO in diseased periwinkle. SPWB-MLO was differentiated serologically from MLOs associated with loofah, paulownia, and Ipomoea obscura witches’ brooms, aster and elm yellows, and rice yellow dwarf in both ELISA and immunofluorescent staining. All monoclonal antibodies cross-reacted with peanut and asparagus bean witches’ broom MLOs and MLOs associated with the witches’ broom weeds, Rhynchosia minima and Alysicarpus vaginalis, found on the Penghu Islands, where there are serious occurences of SPWB.