Nontypable Haemophilus influenzae (NTHi) is a major pathogen in otitis media. It appears to be especially prominent in children with recurrent episodes of acute otitis media (AOM). The broad, long-term objective of this proposal is to define the various roles of lipopolysaccharide (LPS) as a virulence factor in pathogenesis of AOM, with the ultimate goal of developing an LPS inner-core glycoconjugate vaccine against NTHi. Prior efforts in vaccine development have been limited by diversifying selective pressures on surface exposed epitopes of NTHi; however, the use of conserved LPS inner-core may circumvent this limitation. The first specific aim is to identify phenotypic and genotypic changes in NTHi LPS expression during transition from asymptomatic carriage to middle ear disease, in order to identify LPS glycoforms that may have potential as additional vaccine target candidates. Animal modeling in conjunction with mass spectrometry techniques and microarray technology should enable the identification of such critical LPS glycoforms. Secondly, interaction between newly resolved LPS glycoforms and host defense mechanisms will be assessed, by flow cytometry and ELISA techniques.
The final aim i s to determine whether truncated inner-core LPS oligosaccharide structures, when conjugated to a protein carrier, are immunogenic and protective against experimental OM due to both homologous and heterologous isolates of NTHi in a chinchilla animal model. This collaboration between Boston Univ. Medical School, Institute for Biological Sciences NRC-Canada and Oxford University Institute for Molecular Medicine brings together synergistic expertise in microbial genetics and population biology, immunology, LPS structural chemistry, and animal modeling.

Agency
National Institute of Health (NIH)
Institute
National Institute on Deafness and Other Communication Disorders (NIDCD)
Type
Research Project (R01)
Project #
1R01DC005855-01A1
Application #
6678530
Study Section
Special Emphasis Panel (ZDC1-SRB-A (40))
Program Officer
Watson, Bracie
Project Start
2003-08-01
Project End
2007-07-31
Budget Start
2003-08-01
Budget End
2004-07-31
Support Year
1
Fiscal Year
2003
Total Cost
$390,632
Indirect Cost
Name
Boston University
Department
Pediatrics
Type
Schools of Medicine
DUNS #
604483045
City
Boston
State
MA
Country
United States
Zip Code
02118
Lundstrom, Susanna L; Li, Jianjun; Mansson, Martin et al. (2008) Application of capillary electrophoresis mass spectrometry and liquid chromatography multiple-step tandem electrospray mass spectrometry to profile glycoform expression during Haemophilus influenzae pathogenesis in the chinchilla model of experimental oti Infect Immun 76:3255-67
Bouchet, Valerie; Huot, Heather; Goldstein, Richard (2008) Molecular genetic basis of ribotyping. Clin Microbiol Rev 21:262-73, table of contents
Leroy, Magali; Cabral, Howard; Figueira, Marisol et al. (2007) Multiple consecutive lavage samplings reveal greater burden of disease and provide direct access to the nontypeable Haemophilus influenzae biofilm in experimental otitis media. Infect Immun 75:4158-72
Pelton, Stephen I; Huot, Heather; Finkelstein, Jonathan A et al. (2007) Emergence of 19A as virulent and multidrug resistant Pneumococcus in Massachusetts following universal immunization of infants with pneumococcal conjugate vaccine. Pediatr Infect Dis J 26:468-72
Hanage, William P; Huang, Susan S; Lipsitch, Marc et al. (2007) Diversity and antibiotic resistance among nonvaccine serotypes of Streptococcus pneumoniae carriage isolates in the post-heptavalent conjugate vaccine era. J Infect Dis 195:347-52
Figueira, Marisol A; Ram, Sanjay; Goldstein, Richard et al. (2007) Role of complement in defense of the middle ear revealed by restoring the virulence of nontypeable Haemophilus influenzae siaB mutants. Infect Immun 75:325-33
Bouchet, Valerie; Hood, Derek W; Li, Jianjun et al. (2003) Host-derived sialic acid is incorporated into Haemophilus influenzae lipopolysaccharide and is a major virulence factor in experimental otitis media. Proc Natl Acad Sci U S A 100:8898-903