Exploitation of two siderophore receptors, BauA and BfnH, for protection against Acinetobacter baumannii infection.

Abstract

Iron uptake system is expressed in early stages of Acinetobacter baumannii infections under iron-restricted conditions. This study is aimed at the evaluation of immuno-protectivity of BfnH in comparison with BauA in both mature and selected fragmental proteins. The study was designed in single and combined forms of antigens. BfnH is presented in 3472 strains of A. baumannii with more than 97% identity. The preliminary immune-informatics analysis of this protein indicated a region from the β-barrel domain including exposed loops 2-5, with antigenic score comparable to that of BfnH. There was a significant rise in the specific IgG response in all test groups. The bacterial challenge with a lethal dose of A. baumannii demonstrated partial protection of whole proteins which coincides with a significant reduction in the bacterial population colonized in the main organs and an increase in the survival level. Passive immunization of the mice brought about 50% survival in the mice groups immunized with BfnH and with a combination of BfnH and BauA. The protectivity of siderophore receptors suggests their potential immunogenic role that could be considered as a component of multivalent subunit vaccine candidates against A. baumannii.

• Authors: Zahra Aghajani, Iraj Rasooli, Seyed Latif Mousavi Gargari
• Journal: APMIS : acta pathologica, microbiologica, et immunologica Scandinavica (APMIS) Vol. 127 Issue 12 Pg. 753-763 (Dec 2019) ISSN: 1600-0463 [Electronic] Denmark
• PMID: 31512768 (Publication Type: Journal Article)
• Copyright: © 2019 APMIS. Published by John Wiley & Sons Ltd.

Chemical References

• Antibodies, Bacterial
• Bacterial Outer Membrane Proteins
• Bacterial Vaccines
• Epitopes, B-Lymphocyte
• Receptors, Cell Surface
• siderophore receptors

Topics

• Acinetobacter Infections (immunology, microbiology, prevention & control)
• Acinetobacter baumannii (immunology)
• Animals
• Antibodies, Bacterial (blood, immunology)
• Bacterial Load
• Bacterial Outer Membrane Proteins (chemistry, genetics, immunology)
• Bacterial Vaccines (administration & dosage, immunology)
• Epitopes, B-Lymphocyte
• Female
• Immunization
• Immunogenicity, Vaccine
• Mice, Inbred BALB C
• Receptors, Cell Surface (chemistry, genetics, immunology)