Polymer‐grafted starch microparticles for oral and nasal immunization

Abstract

Summary Microparticle delivery systems for oral vaccine administration are receiving considerable attention. A novel silicone polymer-grafted starch microparticle system was developed that is e cacious both orally and intranasally. Unlike most other microparticle systems, this novel system does not appear to retard the release of antigen or to protect antigen from degradation. The results indicate that a unique physiochemical relationship occurs between protein antigen and silicone in a starch matrix that facilitates the mucosal immunogenicity of antigen. This leads to predominance of Th2 antibody response. Taken together, these ®ndings indicate that this novel microparticle system may be advantageous for the delivery of small quantities of antigen, especially intranasally, and may be useful for the induction of oral tolerance.

Starch microparticles as vaccine adjuvant

“…Modification of starch is easily made and can be done in order to decrease swelling or enzymatic degradation [13], or to crosslink the starch into particles, which can be used for entrapment or conjugation of protein molecules [14][15][16]. Such particles are normally biocompatible, taken up by the macrophages of the reticuloendothelial system and degraded in the lysosomes.…”

“…They are too large to be taken up directly by antigen-presenting cells (APCs) but may function as depot formulations in complex with negatively charged antigens (e.g., intramuscularly). [14,29,40] Grafted -Silicone grafted Entrapped 4 -5 Intranasal, intragastric, intraperitoneal [15,16,30,139] Aminated starch/ pullulan Epichlorhydrin Aminated Entrapped 80 -170 -…”

“…The TS-PDMS-grafted starch microparticles with entrapped HSA induced a superior systemic immune response (IgG) compared with the unfunctionalised microparticles. Antigen release studies showed that almost a total release of HSA was reached within 22 and 24 h in aqueous buffer at pH 7.4 [16].…”

The role of adjuvants in the development of mucosal vaccines

“…immunisations and elicit local and systemic humoral responses [116]. However, in comparison to PLG, these microparticles are poorly defined and their biocompatibility has not been tested in humans.…”

Facilitated Production of Secretory IgA against Shiga Toxin B Subunits by Intranasal Application of Antigen‐Coated Polystyrene Microspheres

“…Earlier studies examined effects of microspheres using model antigens with strong immunogenicity such as OVA (20,22,31), human serum albumin (24), bovine serum albumin (1), β-galactosidase and HBs antigen from hepatitis B virus (7). In contrast, our challenge is an improvement of the poor immunogenicity of Stx1B in the mucosal immune system by adsorption on microspheres.…”