Disruption of the cpsE and endA Genes Attenuates Streptococcus pneumoniae Virulence: Towards the Development of a Live Attenuated Vaccine Candidate
| Autor: | Nor Iza A. Rahman, Salwani Ismail, Stuart C. Clarke, Chew Chieng Yeo, Nordin Bin Simbak, Malik Amonov, Wan Mohd Razin Wan Hassan |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
0301 basic medicine
030106 microbiology Immunology Mutant Virulence lcsh:Medicine Biology medicine.disease_cause Article endA Microbiology 03 medical and health sciences vaccine Drug Discovery Glycosyltransferase Streptococcus pneumoniae medicine Pharmacology (medical) Gene capsule biosynthesis gene Gene knockout Pharmacology live attenuated vaccine Attenuated vaccine endonuclease A lcsh:R Biofilm cpsE 030104 developmental biology Infectious Diseases biology.protein |
| Zdroj: | Vaccines Volume 8 Issue 2 Vaccines, Vol 8, Iss 187, p 187 (2020) |
| ISSN: | 2076-393X |
| DOI: | 10.3390/vaccines8020187 |
| Popis: | The majority of deaths due to Streptococcus pneumoniae infections are in developing countries. Although polysaccharide-based pneumococcal vaccines are available, newer types of vaccines are needed to increase vaccine affordability, particularly in developing countries, and to provide broader protection across all pneumococcal serotypes. To attenuate pneumococcal virulence with the aim of engineering candidate live attenuated vaccines (LAVs), we constructed knockouts in S. pneumoniae D39 of one of the capsular biosynthetic genes, cpsE that encodes glycosyltransferase, and the endonuclease gene, endA, that had been implicated in the uptake of DNA from the environment as well as bacterial escape from neutrophil-mediated killing. The cpsE gene knockout significantly lowered peak bacterial density, BALB/c mice nasopharyngeal (NP) colonisation but increased biofilm formation when compared to the wild-type D39 strain as well as the endA gene knockout mutant. All constructed mutant strains were able to induce significantly high serum and mucosal antibody response in BALB/c mice. However, the cpsE-endA double mutant strain, designated SPEC, was able to protect mice from high dose mucosal challenge of the D39 wild-type. Furthermore, SPEC showed 23-fold attenuation of virulence compared to the wild-type. Thus, the cpsE-endA double-mutant strain could be a promising candidate for further development of a LAV for S. pneumoniae. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|