[Specific monoclonal antibodies to the Mycoplasma-type pathogenic agent of grapevine flavescence dorée]

Three hybridomas producing monoclonal antibodies specific for the mycoplasma-like organism (MLO), pathogenic agent of grapevine flavescence dorée, were obtained after fusion between spleen cells from a mouse immunized against flavescence dorée MLO and Sp2/O-Ag-14 mouse myeloma cells. These hybridomas were selected in an indirect sandwich ELISA in which antibodies from two different animal species were used (rabbit and mouse). This assay is convenient for anti-MLO monoclonal antibody screening, because of its sensitivity, specificity and good preservation of antigens. The three monoclonal antibodies were examined for reactivity towards the MLO causal agents of 15 plant yellows. None of the three were implicated in a serological relationship between the MLO of these plant yellows and flavescence dorée-MLO. Reactivity of the three monoclonal antibodies was checked towards two other isolates of flavescence dorée. One of the three antibodies detected the wild isolates.