Mucosa vaccine delivery

Membranous epithelial M cells are a part of the organized mucosa-associated lymphoid tissue (O-MALT). These cells are specialized for antigen sampling. Also, they are exploited as a route of invasion by several pathogens.39 M cells are concentrated in follicle-associated epithelial (FAE) tissue called Peyer s patches in the small intestine. As M cells carry out endocytotic transport, they can be potential vehicles for mucosal drug and vaccine delivery. 

In this paper after explaining why particulate systems are preferred for vaccine delivery, a brief introduction to chitosan will be given, and the importance of chitosan in particulate systems for vaccine delivery will be emphasized according to administration routes, particularly focused on needle-free routes including, oral, mucosal and pulmonary mucosa as well as skin. For comparison, examples on parenteral route will also be mentioned. 

Yang X, Yuan X, Cai D, Wang S, Zong L (2009) Low molecular weight chitosan in DNA vaccine delivery via mucosa. Int J Pharm 375(1-2) 123-132... 

DNA-based vaccines have been recently developed for immunization to overcome the deficiencies of antigen-based vaccines. The major sites of delivery for DNA-based immunization include the oral, nasal, rectal, and vaginal mucosas. The ability of a hepatitis B surface antigen-encoding plasmid to induce... 

Of all the mucosal, nasal mucosa is considered to be the most permeable, offering tremendous scope for peptide delivery, particularly for vaccines (90% of pathogens invade via mucosa).Already, several peptide formulations are on the market, and further developments will depend on clarifying the immunogenicity of bioactive agents on the nasal mucosa and the long-term effect of enhancers on the nasal mucociliary activity. 

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