Immunity to Influenza in Ferrets. IV. Antibody in Nasal Secretions

Abstract

Groups of ferrets were infected with virulent influenza virus A2/Hong Kong/3/68, attenuated influenza virus A2/Hong Kong/1/68, or attenuated influenza virus B/England/13/65. Nasal washings were obtained at various intervals after infection. The results indicated that HAI antibody was present only in nasal washings from ferrets undergoing infection with influenza virus and that the measurement of HAI antibody in nasal washings was a parameter for the assessment of susceptibility to influenza-virus infection. Rate-zonal centrifugation studies on ferret nasal washings collected seven to nine days after infection indicated that the HAI antibody had a sedimentation coefficient of 7S. Similar studies on ferret sera taken seven to nine days after infection showed that the majority of the HAI antibody present in the sera had a sedimentation coefficient of 19S; however, the HAI antibody in sera taken 21 days after infection was a 7S immunoglobulin. Qualitative considerations suggest that at least a part of the antibody present in nasal secretions was produced locally.