Immunization with high-molecular-weight adhesion proteins of nontypeable Haemophilus influenzae modifies experimental otitis media in chinchillas

• DOI: 10.1128/iai.64.4.1246-1251.1996
• Publication Date: 2020-01-06T19:01:57Z
• Authors: S J Barenkamp
• Keywords: Antibody titer

Prevention of nontypeable Haemophilus influenzae otitis media by vaccination is an important health care goal. Proteins in bacterial adherence deserve consideration as potential vaccine candidates. Two colleagues and I previously identified a family immunogenic high-molecular-weight proteins H. to human epithelial cells (J.W. St. Geme III, S. Falkow, S.J. Barenkamp, Proc. Natl. Acad. Sci. USA, 90:2875-2879, 1993). In the work described here, determined whether immunization with two such proteins, HMW1 HMW2, purified from prototype strain 12, would modify course experimental caused homologous strain. Chinchillas received three monthly subcutaneous injections 40 microgram HMW1/HMW2 protein mixture Freud's adjuvant. One month after last injection, animals were challenged intrabullar inoculation 300 CFU 12. Infection developed five control versus 5 10 immunized (P = 0.08, Fisher exact, one-tailed). Among infected animals, counts middle ear fluid specimens 7 days postchallenge significantly greater than 0.014, Mann-Whitney U test). Serum antibody titers following comparable uninfected animals. However, infection was uniformly associated appearance bacteria downregulated expression suggesting selection response immunologic pressure. Although protection incomplete, these data suggest that adhesion are potentially protective antigens which might represent one component multicomponent vaccine.