Mucosal route, vaccination

Mucosal Route. Vaccination through mucosal routes... 

Hillery, A.M., Microparticulate Delivery Systems Potential Drug/Vaccine Carriers via Mucosal Routes, Pharmaceutical Science and Technology Today. 1, 69, 1998. 

The induction of an immune response by various mucosal routes is an important approach for the control of mucosally acquired infections. The apparent linked nature of the mucosal immune system enables the delivery of an antigen to any mucosal surface to have the secondary effect of potentially inducing immunity at others. Induction of a combination of systemic and secretory immune responses can be determined by the nature of the antigen, the route of administration, and the delivery system utilized. For example, traditional parenteral vaccines primarily induce IgM and IgG responses, whereas mucosal vaccination can elicit both IgG and secretory IgA responses (Corthesy, 2007). 

Loss of vaccine by any first-pass effects could be minimized by avoiding the intravenous route and careful selection of mucosal routes would be of benefit. Indeed, unlike small molecular weight drugs, vaccines are not administered through the IV route and alternatives are required. 

Mestecky, J., et al. 1997. Current options for vaccine delivery systems by mucosal routes. J Control Release 48 243. 

The success of vaccination depends primarily on the method of presenting the antigen to the host immune system. Antigens have usually been delivered by parenteral (such as intravenous, intramuscular, intraperito-neal, intradermal, and subcutaneous) administration, but recent studies have shown that other routes of delivery such as intranasal, oral, and transdermal delivery have also been effective. In some cases, vaccination through mucosal routes resulted in better responses in IgA production. Because non-parenteral vaccine delivery presents many obvious advantages, numerous attempts have been made on the development of non-parenteral delivery of vaccines. 

An additional route of uptake upon peroral administration is the passage of the M-cells of the Peyer s patches [18]. Although this route in essence has only a low transport capacity, it is of importance for mucosal (peroral) vaccination, for example. The Peyer s patches are located in the small intestine where M-cells, which neither possess a mucus nor a glycocalix layer in comparison to the adjacent enterocytes, allow the drug uptake via transcytosis. The drug is then transported into the lymphatic system and causes an immune response in the case of the vaccination approach. Absorption via M-cells in essence is possible due to the decreased enzymatic activity and their rather high permeability. 

Ryan EJ, Daly LM, Mills KH (2001) Immunomodulators and delivery systems for vaccination by mucosal routes. Trends Biotechnol 19(8) 293-304... 

Virosomes are viral glycoproteins encapsulated in lipid vesicles, which have been shown to be effective as experimental vaccines delivered by both mucosal and systemic routes. Viruses and their surface glycoproteins have a high affinity for receptors on mucosal surfaces, especially along the respiratory tract. 

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. 

Vaccination by the nasal route produces a mucosal protection using mucus, the epithelial surface, and both innate and acquired immune responses. The innate defense mechanism plays a very important role in that it influences the type of acquired immune mechanism, which mainly responds on the basis of immune memory. The ability to attain these responses is the main principle of attaining protection from infection. 

The nasal delivery of vaccines is a very attractive route of administration in terms of efficacy and consumer friendliness. A population-wide immunization against influenza has yet to be achieved. The pain of injections discourages many people from receiving a flu shot. The nasal route offers the advantage of a mucosal response followed by a seric response, and has proved to be a very efficient mode of administration. ... 

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