Plant-Based Oral Vaccines: Molecular Biotechnology Approaches Toward Functional Food-Based Immunization.

Plant-based oral vaccines are now becoming a more transformative medical form in immunotherapy; they are cheap and needle-free. These systems use natural bioencapsulation in plant cell walls, which preserves antigen stability within the gastrointestinal tract and promotes targeted release to mucosal immune tissues. Tests indicate that plant-derived antigens preserved their structure after exposure and they produced robust mucosal IgA and systemic IgG responses. From the early trial, such as seroconversion among human subjects consuming hepatitis B surface antigen (HBsAg)-expressing potatoes and high mucosal immunity generated by CTB-producing plants, promising results show their immunogenic potential. These technologies including chloroplast transformation that can produce more than 100 times higher antigen yields, CRISPR/Cas9 precision editing, and AI-equipped antigen design, further strengthen this platform. Although their relative strengths in standardization and poor digestibility are not widely available, plant-based oral vaccines have proven clear success with significant potential for immunization through functional foods, especially for resource-limited areas.