Serum-neutralizing, non-precipitating, partially protective monoclonal IgA antibody against VSV-NJ

A BALB/c mouse hybridoma that secretes an isotype IgA kappa-antibody specific for the New Jersey serotype of vesicular stomatitis virus (VSV-NJ) has been cloned. This antibody is serum-neutralizing yet fails to immunoprecipitate 35S-labeled G glycoprotein from virus-infected cell lysates. To determine if the antibody could protect mice from a lethal challenge dose of VSV-NJ, passive transfer experiments were performed with ascites fluid containing the IgA antibody. Mice given antibody IP or IV 24 hr before challenge all succumbed to progressive encephalitis, as did control mice. The only mice to survive were those given a virus preparation that had been preincubated with the ascites fluid for 1 hr at 370C. To characterize this antibody physically, Coomassie-stained polyacrylamide gels were prepared in which samples of affinity-purified antibody were prepared under reducing and non-reducing conditions. The results indicate that the molecule is composed of a disulfide bonded light-chain dimer and a disulfide bonded heavy-chain dimer