Cross-reactive antibodies in type b and nontypeable Hemophilus influenzae-induced experimental otitis media.

Cross-reactive antibodies directed against type b (TBHI) or serologically nontypeable (NTHI) strains of Hemophilus influenzae were investigated in experimental otitis media. Cross-reactive antibody to TBHI was demonstrated in sera and middle ears from chinchillas infected with an NTHI, and cross-reactive antibody to NTHI developed in sera and middle ears of chinchillas challenged with TBHI. The absorption test data presented indicate that the sera and middle ear effusions from chinchillas challenged with either TBHI or NTHI had not only specific antibody activity to the challenged strain but also antibody activities against the probable common cell antigens of H influenzae. These data indicate that it may be possible to develop a polyvalent vaccine effective against the various and divergent strains of H influenzae, including the serologically nontypeable isolates.