Encapsulation of rotavirus into poly(lactide-co-glycolide) microspheres.

Area of Science:

• Biotechnology
• Vaccine Development
• Materials Science

Background:

• Poly(lactide-co-glycolide) (PLG) microspheres are promising for vaccine delivery.
• Incorporating sensitive antigens like formaldehyde-inactivated rotavirus particles (FRRV) into PLG microspheres requires optimized formulation techniques.
• Ensuring antigen stability and controlled release is crucial for vaccine efficacy.

Purpose of the Study:

• To develop and optimize two small-scale double emulsion techniques for encapsulating FRRV into PLG microspheres.
• To compare the effects of high-speed homogenization versus vortex mixing on microsphere characteristics and FRRV release.
• To evaluate the immunogenicity of FRRV-loaded PLG microspheres in vivo.

Main Methods:

• Developed two double emulsion methods for FRRV encapsulation in PLG.
• Investigated high-speed homogenization and vortex mixing for the second emulsification step.
• Characterized microsphere size, entrapment efficiency, and in vitro FRRV release.
• Assessed serum IgG antibody response in mice post-immunization via ELISA.

Main Results:

• Vortex mixing yielded a stable double emulsion, unlike high-speed homogenization.
• Both methods produced microspheres in the 1-10 micrometer range.
• The vortex technique demonstrated greater robustness and predictability compared to homogenization.
• PLG-FRRV microspheres elicited an IgG antibody response comparable to free FRRV, indicating retained antigenicity.

Conclusions:

• Vortex mixing is a robust and suitable method for preparing PLG microspheres containing FRRV.
• The antigenicity of FRRV is maintained during encapsulation using the optimized vortex technique.
• PLG-FRRV microspheres represent a viable formulation for rotavirus vaccination, eliciting a strong immune response.