Optimization and scale-up production of Zika virus Delta NS1 in Escherichia coli: application of Response Surface Methodology

Author(s)

Kanno, Alex Issamu ^[1] ; de Cerqueira Leite, Luciana Cezar ^[1] ; Pereira, Lennon Ramos ^[2] ; Rodrigues de Jesus, Monica Josiane ^[2] ; Andreata-Santos, Robert ^[2] ; dos Santos Alves, Rubens Prince ^[2] ; Durigon, Edison Luiz ^[3] ; de Souza Ferreira, Luis Carlos ^[2] ; Goncalves, Viviane Maimoni ^[1]

Affiliation

^[1] Inst Butantan, Lab Desenvolvimento Vacinas, Ave Vital Brasil 1500, BR-05503900 Sao Paulo, SP - Brazil

^[2] Univ Sao Paulo, Lab Desenvolvimento Vacinas, Inst Ciencias Biomed, Sao Paulo, SP - Brazil

^[3] Univ Sao Paulo, Lab Virol, Inst Ciencias Biomed, Sao Paulo, SP - Brazil

• Document type: Journal article
• Source: AMB EXPRESS; v. 10, n. 1 DEC 2020.
• Web of Science Citations: 0

Abstract

Diagnosing Zika virus (ZIKV) infections has been challenging due to the cross-reactivity of induced antibodies with other flavivirus. The concomitant occurrence of ZIKV and Dengue virus (DENV) in endemic regions requires diagnostic tools with the ability to distinguish these two viral infections. Recent studies demonstrated that immunoassays using the C-terminal fragment of ZIKV NS1 antigen (Delta NS1) can be used to discriminate ZIKV from DENV infections. In order to be used in serological tests, the expression/solubility of Delta NS1 and growth of recombinant E. coli strain were optimized by Response Surface Methodology. Temperature, time and IPTG concentration were evaluated. According to the model, the best condition determined in small scale cultures was 21 degrees C for 20 h with 0.7 mM of IPTG, which predicted 7.5 g/L of biomass and 962 mg/L of Delta NS1. These conditions were validated and used in a 6-L batch in the bioreactor, which produced 6.4 g/L of biomass and 500 mg/L of Delta NS1 in 12 h of induction. The serological ELISA test performed with purified Delta NS1 showed low cross-reactivity with antibodies from DENV-infected human subjects. Denaturation of Delta NS1 decreased the detection of anti-ZIKV antibodies, thus indicating the contribution of conformational epitopes and confirming the importance of properly folded Delta NS1 for the specificity of the serological analyses. Obtaining high yields of soluble Delta NS1 supports the viability of an effective serologic diagnostic test capable of differentiating ZIKV from other flavivirus infections. (AU)

• FAPESP's process: 12/23124-4 - Investigating the effector mechanisms of the Schistosoma mansoni attenuated vaccine by Systems Vaccinology
• Grantee: Luciana Cezar de Cerqueira Leite
• Support Opportunities: Regular Research Grants
• FAPESP's process: 14/17595-0 - New vaccine research based on recombinant proteins of dengue virus
• Grantee: Luis Carlos de Souza Ferreira
• Support Opportunities: Regular Research Grants
• FAPESP's process: 16/20045-7 - Antigen discovery and development of serological diagnostic methods and vaccine approaches against the Zika Virus (ZIKV)
• Grantee: Luis Carlos de Souza Ferreira
• Support Opportunities: Research Projects - Thematic Grants