[Development of microencapsulating measles live vaccine]

Area of Science:

• Immunology
• Vaccinology
• Biotechnology

Background:

• Non-injection immunization methods are increasingly important for measles prevention.
• Mucosal vaccines offer potential for effective "entry gate" immunity against airborne infections like measles.

Purpose of the Study:

• To develop and evaluate microencapsulated measles vaccines for non-invasive administration.
• To investigate the efficacy of pH-dependent polymer-based microcapsules for measles virus delivery.

Main Methods:

• Microencapsulation of live measles virus particles within pH-dependent polymer matrices.
• Characterization of microcapsule particle size (0.6-2.0 microm) and viral activity (3.36-4.31 log TCD50/0.5 ml).
• Subcutaneous and intranasal immunization studies in guinea pigs using various polymer formulations.

Main Results:

• Single subcutaneous administration of ethylcrylate, sodium alginate/chitosan, or sodium alginate/HMDA microcapsules showed promising results.
• Intranasal administration required multiple immunizations (2-3 stages) for sodium alginate/spermin and sodium alginate/HMDA formulations.
• Successful creation of microencapsulated live measles vaccine with preserved viral activity.

Conclusions:

• Microencapsulation in pH-dependent polymers is a viable strategy for developing non-injection measles vaccines.
• Specific polymer formulations demonstrate differential efficacy depending on the administration route (subcutaneous vs. intranasal).
• Further research into optimized formulations and administration protocols is warranted for intranasal delivery.