Concerns of Acinetobacter baumannii infection have increased due to the emergence of multi-drug resistance. In the present study, we determined the capsular polysaccharide (CPS) structure of A. baumannii SK44, a clinical isolate from Taiwan, to consist of pentasaccharide repeats. We found that CPS-induced antibody provided 55% protection against challenge in an animal model. The CPS-specific antibody reacted with the surface components of about 62% clinical isolates (342/554 strains) from cross-sectional and longitudinal studies by dot-immunoassay. Pulsed-field gel electrophoresis of positive strains showed the antibody covered different clonalites of A. baumannii clinical isolates. Meanwhile, using the CPS antibody as a probe, we found a number of outer membrane proteins bound to the antibody, including OmpA/motB, TonB-dependent receptor, and Omp38, indicating their association with CPS. These results might lead to the use of the capsular polysaccharide as a vaccine to prevent A. baumannii infection.
NCBI PubMed ID: 28190743Publication DOI: 10.1016/j.vaccine.2017.01.060Journal NLM ID: 8406899Publisher: Elsevier
Correspondence: shwu
gate.sinica.edu.tw
Institutions: Institute of Biological Chemistry, Academia Sinica, Taipei 115, Taiwan, National Health Research Institutes, Miaoli County 35053, Taiwan, School of Medicine, National Yang-Ming University, Taipei 112, Taiwan, Department of Emergency Medicine, Taipei Veterans General Hospital, Taipei 112, Taiwan, Human Health Therapeutics, National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A0R, Canada, Institute of Microbiology, Tzu Chi University, Hualien 907, Taiwan
Methods: 13C NMR, 1H NMR, methylation, NMR-2D, GC-MS, sugar analysis, acid hydrolysis, MS/MS, serological methods, enzymatic digestion, statistical analysis, SEC, immunization, conjugation, pulsed-field gel electrophoresis (PFGE)
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