Immunization chitosan microspheres

Chitosan microparficles provide a pofenfial system for oral vaccination. While oral vaccinations would cost less and be more comfortable than traditional injections, antigen degradation in the acidic stomach environment and unpredictable immune response at Peyer s patches render them inefficient. However, vaccines delivered in biodegradable microspheres can weather the harsh gastrointestinal environment and be phagocytized by Peyer s patch cells. Wan der Lubben et al. demonstrated that chitosan microspheres loaded with FITC labeled ovalbumin relayed their antigens to Peyer s patches. Stained intestinal epithelium showed high uptake of loaded microspheres, while pure administered FITC-ovalbumin indicated no uptake. 

Chitosan microspheres act as promising carriers for oral pDNA vaccine in comparison with fish vaccinated with naked pDNA A relative percent survival (RPS) rate of 46% was recorded. Sea bass (Lales calcarifer) orally vaccinated with chitosan-DNA (pVAOMP38) complex showed moderate protection against experimental V. anguillarum infection Squalane oil-containing W/O/W multiple emulsion formulations can significantly enhance the local and systemic immune responses, especially after oral administration... 

Jiang, H.L., Park, I.K., Shin, N.R. et al. 2004. In vitro study of the immune stimulating activity of an atrophic [correction of athrophic] rhinitis vaccine associated to chitosan microspheres. Eur. J. Pharm. Biophatm. 58 471-176. 

Jiang, H.L., Kang, M.L., Quan, J.S. et al. 2008. The potential of mannosylated chitosan microspheres to target macrophage mannose receptors in an adiuvant-dehvery system for intranasal immunization. Biomaterials. 29 1931-1939. 

Kang, M.L., Kang, S.G., Jiang, H.L. et al. 2006. In vivo induction of mucosal immune responses by intranasal administration of chitosan microspheres containing Bordetella brvnchiseptica DNT. Eur. J. Pharm. Biopharm. 63 215-220. 

Oral DNA-based immunotherapy which is a new treatment option for fish inununization in intensive culture to prevent from lymphocystis disease has been reported to have some limitations. Due to the existence of the nucleases and severe gastrointestinal conditions, DNA-based vaccines can be hydrolyzed or denatured when given orally. Chitosan microspheres (<10pm) that contained about twice the amount of pDNA that is generally given to fish by injection route were shown to result in significant pDNA expression in fish after oral administration (Tian et al. 2008) In comparison to immunization via injection with naked pDNA, oral administration of chitosan microspheres loaded with pDNA vaccine were reported to be more stable and last longer for the immunization of fish. 

Tian, J., J. Yu, and X. Sun. 2008. Chitosan microspheres as candidate plasmid vaccine carrier for oral immunization of Japanese flounder (Paralichthys olivaceus). Veterinary Immunology and Immunopathology... 

Zhou X, Liu B, Yu X et al (2007) Controlled release of PEI/DNA complexes from maimose-bearing chitosan microspheres as a potent delivery system to enhance immune response to HBV DNA vaccine. J Control Release 121 200-207... 

Jiang, HL Park, IK Kang, ML Yoo, HS Choi, YJ Akaike, T Cho, CS. Immune stimulating activity of an atrophic rhinitis vaccine associated to pegylated chitosan microspheres in vitro. Polymers for Advances Technologies, 18 (3), 2007, 220-225. 

Microspheres Ionic gelation with tripolyphosphate Bordetella, bronchiseptica, dermonecrotoxin Chitosan In mice Systemic and mucosal immune responses induced 21... 

It is generally believed that microspheres that adhere to the nasal mucus elicit better immune response, and for this reason, many microspheres made of mucoadhesive polymers, such as chitosan, have been used extensively in the preparation of nasal vaccine formulations. 

Pandit, S., Cevher, E., Zariwala, M.G., Somavarapu, S., and Alpar, H.O. 2007. Enhancement of immune response of HBsAg loaded poly (L-lactic acid) microspheres against hepatitis B through incorporation of alum and chitosan. J. Microencapsul. 24 539-552. 

Use of chitosan in intranasal boost led to protection of fom of six animals suggesting that this approach may be worth optimizing further Inunune response was enhanced in the presence of genetic adjuvants but not with chitosan Significant immunization efficacy of microspheres loaded with pDNA and resistance to degradation in simulated gastroinlestinal tract environment... 

Streptococcus equi subsp. equi, which is the causative agent of Strangles, was adsorbed onto poly-e-caprolactone microspheres with chitosan-modilied surfaces (Florindo et al. 2008). After subcutaneous immunization of mice, the formulations induced higher lymphokines levels than did the free antigen, in accordance with cellular and humoral immune responses, successfully activating the paths leading to Thl and Th2 cells. More pronounced responses were observed with chitosan-surface-modifled PCL microspheres than those of the unmodified formulations. 

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