Modification of otitis media in chinchillas rechallenged with nontypable Haemophilus influenzae and serological response to outer membrane antigens.
Otitis media was produced in chinchillas by right-sided intrabullar inoculation with nontypable Haemophilus influenzae, and susceptibility to reinfection was investigated. After resolution of initial right-sided infection, animals underwent ipsilateral or contralateral intrabullar rechallenge with the same strain. After ipsilateral rechallenge right ears were completely protected against reinfection; previously uninfected left ears were similarly protected on contralateral rechallenge. Previously infected ears remained fully susceptible to infection with a heterologous strain of nontypable H. influenzae. Using an enzyme-linked immunosorbent assay, we measured the serological response to outer membrane protein and lipopolysaccharide antigens during initial infection. A greater than or equal to 10-fold rise in titer of antibody to homologous outer membrane proteins was observed in all 11 animals tested. Most animals exhibited a minimal serological response to lipopolysaccharide. Thus experimental otitis media due to nontypable H. influenzae induces strain-specific protective immunity and a concomitant serological response to outer membrane proteins.
D000818:Animals; D000907:Antibodies, Bacterial / Q000032:analysis / Q000096:biosynthesis*; D000942:Antigens, Bacterial / Q000276:immunology*; D001425:Bacterial Outer Membrane Proteins / Q000276:immunology*; D002682:Chinchilla; D003429:Cross Reactions; D004797:Enzyme-Linked Immunosorbent Assay; D006192:Haemophilus Infections / Q000276:immunology*; D006193:Haemophilus influenzae / Q000276:immunology*; D008070:Lipopolysaccharides / Q000276:immunology; D010033:Otitis Media / Q000276:immunology*; D010034:Otitis Media with Effusion / Q000209:etiology / Q000276:immunology*
D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D008070:Lipopolysaccharides