Bacillus subtilis comes of age as a vaccine production host and delivery vehicle

Abstract

Bacillus subtilis is a vaccine production host and delivery vector with several advantages such as a low production cost, straightforward administration as it is safe for human consumption and the production of spores exerting adjuvant effects. This review summarizes the expression approaches and provides an updated outlook of how a myriad of pathogens have been targeted under this technology. Furthermore, by reviewing the literature, several promising candidates in terms of immunogenic and immunoprotective potential have been identified. The immune profiles achieved comprise either humoral or cellular responses, which reflect versatility for application in the fight of distinct pathologies that demand specific polarization on the immune responses. Some perspectives for this field are also envisioned.

Keywords:

• cytotoxic lymphocyte
• delivery vehicle
• intranasal immunization
• low cost vaccine
• mucosal vaccines
• oral immunization
• particulate antigen
• spore
• sublingual immunization

Financial & competing interest’s disclosure

S Rosales-Mendoza was supported by CONACYT/Mexico CONACYT (grant INFR-2014-01-225843) and PROFOCIES 2014. CE Angulo was supported by CONACYT (grants CB-2010-01, 151818 and INFR-2014-01, 225924). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Key issues

• Bacillus subtilis constitutes a vaccine biofactory and delivery vehicle of low production cost, straightforward administration and attractive immunogenic properties.

• The technologies that allow for the design of B. subtilis-based vaccines are summarized.

• An updated outlook of the pathogens targeted under this technology is provided.

• Several vaccine candidates have been evaluated with promising findings in terms of the induction of effective humoral and cellular immunoprotective responses.

• Perspectives for the development and evaluation of B. subtilis-based vaccines are identified.

Notes