สถาบันวิจัยวิทยาศาสตร์สาธารณสุข

National Institute of Health of Thailand

Characterization of chikungunya virus-like particles

Authors : Nitchakarn Noranate, 1 , * Naokazu Takeda, 1 , 3 Prukswan Chetanachan, 2 Pathompong Sittisaman, 2 Atchareeya A-nuegoonpipat, 2 and Surapee Anantapreecha 2

 

Affiliations : 

1 Thailand-Japan Research Collaboration Center on Emerging and Re-emerging Infections (RCC-ERI), Nonthaburi, Thailand
2 National Institute of Health, Department of Medical Sciences, Ministry of Public Health, Nonthaburi, Thailand
3 Research Institute for Microbial Diseases, Osaka University, Osaka, Japan

 

Source :

PLOS ONE, September 2014, Vol. 9, Issue 9, e108169

 

Language :

English

 

Abstract :

 
 

Chikungunya virus (CHIKV) is becoming a global concern due to the increasing number of outbreaks throughout the world and the absence of any CHIKV-specific vaccine or treatment. Virus-like particles (VLPs) are multistructured proteins that mimic the organization and conformation of native viruses but lack the viral genome. They are noninfectious and potentially safer vaccine candidates. Recent studies demonstrated that the yield of CHIKV VLPs varies depending on the strains, despite the 95% amino acid similarity of the strains. This might be due to the codon usage, since protein expression is differently controlled by different organisms. We optimized the region encoding CHIKV structural proteins, C-E3-E2-6k-E1, inserted it into a mammalian expression vector, and used the resulting construct to transfect 293 cells. We detected 50-kDa proteins corresponding to E1 and/or E2 in the cell lysate and the supernatant. Transmission electron microscopy revealed spherical particles with a 50- to 60-nm diameter in the supernatant that resembled the native CHIKV virions. The buoyant density of the VLPs was 1.23 g/mL, and the yield was 20 µg purified VLPs per 108 cells. The VLPs aggregated when mixed with convalescent sera from chikungunya patients, indicating that their antigenicity is similar to that of native CHIKV. Antibodies elicited with the VLPs were capable of detecting native CHIKV, demonstrating that the VLPs retain immunogenicity similar to that of the native virion. These results indicated that CHIKV VLPs are morphologically, antigenically, and immunologically similar to the native CHIKV, suggesting that they have potential for use in chikungunya vaccines.

 

Link :

PLOS One : http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0108169

NCBI : https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4180278/