Specificity of the Antibody Response of Human Beings to Strains of Influenza Virus

Abstract

Summary Acute and convalescent sera from cases of influenza A have been tested for neutralizing antibodies to PR8, W.S., and Melbourne strains of influenza A, the Lee strain of influenza B, and the swine influenza virus by the chicken-cell agglutination method. Considerable specificity was demonstrated between PR8 and W.S. and swine influenza. It was also indicated that the strain-specificity was not limited to those producing poor rises to PR8, but occurred in some cases producing good rises to PR8. Mouse neutralization tests on selected cases confirmed the results obtained by the agglutinative test. Persons vaccinated with influenza A vaccines whose sera were tested with the same virus strains were found to be somewhat more specific in their antibody response to strains PR8, W.S., and swine than were the sera of infected individuals. This apparent increase of specificity may be due, in part at least, to the fact that the response to the vaccine was not as great as was the response to an attack of influenza A. Sera of several persons infected or vaccinated with influenza A showed also an output of antibodies to the Lee strain of influenza B. Some of these apparent increases in reactivity may have been due, however, to the partial destruction of antibodies by a contaminant in the preliminary serum specimens. A few individuals vaccinated with active Melbourne vaccine showed a better response to Melbourne than to PR8. Conversely, those vaccinated with PR8-distemper virus vaccine responded better to PR8 than to Melbourne.