Cross-protection induced by highly conserved outer membrane proteins (Omps) in mice immunized with OmpC of Salmonella Typhi or OmpK36 of Klebsiella pneumoniae. Issue 18 (20th April 2022)

• Record Type: Journal Article
• Authors: Liu, Esther Yip-Mei; Chen, Jiun-Han; Lin, Jung-Chung; Wang, Ching-Hsun; Fung, Chang-Phone; Ding, Yi-Jiun; Chang, Feng-Yee; Siu, L. Kristopher
• Is Part Of: Vaccine. Volume 40:Issue 18(2022)
• Page Start: 2604
• Page End: 2611
• Publication Date: 2022-04-20
• Subjects: OmpC -- OmpK36 -- S. Typhi -- K. pneumoniae -- Vaccination; Vaccines -- Periodicals; 615.372
• DOI: 10.1016/j.vaccine.2022.03.016
• Languages: English
• ISSNs: 0264-410X

Abstract

Abstract: Background/purpose: Outer membrane proteins (Omps) are a family of proteins that are highly conserved throughout the evolution of Enterobacteriaceae. Previous studies using sequence comparisons have found a high degree of sequence homology between OmpK36 of Klebsiella pneumoniae and OmpC of Salmonella enterica serovar Typhi. Whether highly conserved OmpC can be directly extrapolated as a common vaccine candidate against K. pneumoniae or other Enterobacteriaceae remains to be verified. Methods: OmpK36 and OmpC were purified and used to immunize BALB/c mice. After immunization, five mice from each group were injected intraperitoneally with a cell suspension of K. pneumoniae or S. Typhi, and the mice were monitored daily for 14 days to measure the severity of illness and assess their survival. Results: Cross-reacting OmpK36 and OmpC antibodies were identified in the mice immunized with OmpK36 or OmpC. No cross-protection was observed in the mice immunized with OmpC in the presence of K. pneumoniae infection. Conclusion: Although a high degree of similarity was observed for the amino acid sequences between OmpK36 and OmpC, our results suggested that no cross-protection occurred in the mice challenged with other species.