Mucosal Immunization Using Recombinant Probiotic-based Vaccines: A Smart Approach Using Next-Generation Probiotics (NGPs)

Background and Objective: The mucosal immune system plays a vital role as the body's first line of defense against pathogens; however, traditional injectable vaccines are often inefficient in inducing sustained immune responses at mucosal surfaces. This article aims to review the potential of Next-Generation Probiotics (NGPs) as smart and novel carriers for mucosal immunization.

Methods: In this review, the distinct features of NGPs compared to traditional probiotics, the design mechanisms of vaccines based on these microorganisms, and their interaction with the host immune system are analyzed. Furthermore, the advantages, clinical challenges, and regulatory hurdles associated with this technology are examined. Findings: The results indicate that NGPs (such as Akkermansia muciniphila and Faecalibacterium prausnitzii) and engineered Lactococcus lactis are promising platforms for antigen delivery due to their natural symbiosis with humans and strong immunomodulatory properties. These vaccines can increase vaccination coverage by simultaneously stimulating mucosal (IgA) and systemic immunity and eliminating the need for injections. However, challenges such as oxygen sensitivity, biosafety considerations, and strict regulations exist.

Conclusion: Next-generation probiotics have opened a new window in vaccinology. Despite current obstacles, advancements in synthetic biology and formulation can transform NGPs into powerful tools for preventing infectious diseases and treating inflammatory disorders in the future.