A novel platform for virus-like particle-display of flaviviral envelope domain III: induction of Dengue and West Nile virus neutralizing antibodies

Abstract

CD16-RIgE is a chimeric human membrane glycoprotein consisting of the CD16 ectodomain fused to the transmembrane domain and cytoplasmic tail of the gamma chain of the high affinity receptor of IgE (RIgE). Coexpression of CD16-RIgE and HIV-1 Pr55Gag polyprotein precursor (Pr55GagHIV) in insect cells resulted in the incorporation of CD16-RIgE glycoprotein into the envelope of extracellular virus-like particles (VLPs), a phenomenon known as pseudotyping. Taking advantage of this property, we replaced the CD16 ectodomain of CD16-RIgE by the envelope glycoprotein domain III (DIII) of dengue virus serotype 1 (DENV1) or West Nile virus Kunjin (WNVKun). The two resulting chimeric proteins, DIII-DENV1-RIgE and DIII-WNVKun-RIgE, were addressed to the plasma membrane, exposed at the surface of human and insect cells, and incorporated into extracellular VLPs when coexpressed with Pr55GagHIV in insect cells. The DIII domains were accessible at the surface of retroviral VLPs, as shown by their reactivity with specific antibodies, and notably antibodies from patient sera. The DIII-RIgE proteins were found to be incorporated in VLPs made of SIV, MLV, or chimeric MLV-HIV Gag precursors, indicating that DIII-RIgE could pseudotype a wide variety of retroviral VLPs. VLP-displayed DIII were capable of inducing specific neutralizing antibodies against DENV and WNV in mice. Although the neutralization response was modest, our data confirmed the capability of DIII to induce a flavivirus neutralization response, and suggested that our VLP-displayed CD16-RIgE-based platform could be developed as a vaccine vector against different flaviviruses and other viral pathogens.

Cell attenuated porcine epidemic diarrhea virus strain Zhejiang08 provides effective immune protection attributed to dendritic cell stimulation

“…Three groups were intramuscularly immunized with 1 mL of CV777 (10 5.0 TCID50/mL), 1 mL of Zhe-jiang08 (10 5.0 TCID50/mL), and the same volume of saline, respectively, all of which were emulsified with complete Freund's adjuvant. Subsequent to immunization, sera samples from piglets of the three different groups were collected at 7 d until 150 d after immunization to explore whether piglets generated PEDV neutralizing antibodies as previously described [19]. On the 14th day after immunization, 18 piglets were chosen, and assigned to groups with six piglets per group.…”

An Overview of Current Approaches Toward the Treatment and Prevention of West Nile Virus Infection

“…Using this retrovirus based VLPs platform, a WNV vaccine was generated by replacement of the CD16 ectodomain in CD16-RIgE glycoprotein with EDIII of WNV, which induced neutralizing antibodies in mice [ 139 ].…”

Current trends in West Nile virus vaccine development

“…Using a 13-kDa DIII recombinant protein for vaccination, mice mounted significant PRNT 50 serum titers (1:1,000) against the lineage 2 WNV-Sarafend strain following three immunizations with 100 μg of antigen per dose [98]. Other groups have pursued vaccines based on VLP platforms that incorporate fusion proteins engineered to display the WNV Env DIII on their surface, but results have varied [99,100]. In one study using an HIV-based VLP, only 1/5 mice seroconverted (PRNT 50 ≥ 1:10) against the lineage 1 WNV-Kunjin strain following vaccination [100].…”

“…Other groups have pursued vaccines based on VLP platforms that incorporate fusion proteins engineered to display the WNV Env DIII on their surface, but results have varied [99,100]. In one study using an HIV-based VLP, only 1/5 mice seroconverted (PRNT 50 ≥ 1:10) against the lineage 1 WNV-Kunjin strain following vaccination [100]. Using a bacteriophage expression system, another DIII-based VLP vaccine was shown to induce neutralizing responses against WNV-NY99 in mice following a single immunization and partial protection against lethal WNV challenge (PRNT 100 ~1:20-1:30, 60% survival), but higher neutralizing titers and full protective immunity (PRNT 100 ~1:1,000, 100% survival) were achieved after three doses [99].…”