Concentrated protein body product derived from rice endosperm as an oral tolerogen for allergen-specific immunotherapy--a new mucosal vaccine formulation against Japanese cedar pollen allergy.

Abstract

The endoplasmic reticulum-derived type-I protein body (PB-I) from rice endosperm cells is an ideal candidate formulation for the oral delivery of bioencapsulated peptides as tolerogens for allergen-specific immunotherapy. In the present study, PBs containing the deconstructed Japanese cedar pollen allergens Cryptomeria japonica 1 (Cry j 1) and Cry j 2 were concentrated by treatment with thermostable α-amylase at 90°C to remove the starch from milled rice powder, which resulted in a 12.5-fold reduction of dry weight compared to the starting material. The modified Cry j 1 and Cry j 2 antigens in this concentrated PB product were more resistant to enzymatic digestion than those in the milled seed powder despite the absence of intact cell wall and starch, and remained stable for at least 10 months at room temperature without detectable loss or degradation. The high resistance of these allergens could be attributed to changes in protein physicochemical properties induced by the high temperature concentration process, as suggested by the decreased solubility of the antigens and seed proteins in PBs in step-wise-extraction experiments. Confocal microscopy showed that the morphology of antigen-containing PB-Is was preserved in the concentrated PB product. The concentrated PB product induced specific immune tolerance against Cry j 1 and Cry j 2 in mice when orally administered, supporting its potential use as a novel oral tolerogen formulation.

• Authors: Yuhya Wakasa, Hidenori Takagi, Nobumasa Watanabe, Noriko Kitamura, Yoshihiro Fujiwara, Yuko Ogo, Shimpei Hayashi, Lijun Yang, Masaru Ohta, Wai Wai Thet Tin, Kenji Sekikawa, Makoto Takano, Kenjirou Ozawa, Takachika Hiroi, Fumio Takaiwa
• Journal: PloS one (PLoS One) Vol. 10 Issue 3 Pg. e0120209 ( 2015) ISSN: 1932-6203 [Electronic] United States
• PMID: 25774686 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Allergens
• Antigens, Plant
• Organic Chemicals
• Recombinant Proteins
• Tolerogen
• Vaccines
• Pepsin A

Topics

• Allergens (immunology)
• Animals
• Antigens, Plant (chemistry, immunology)
• Cryptomeria (immunology)
• Desensitization, Immunologic
• Disease Models, Animal
• Endosperm (chemistry)
• Immunity, Mucosal (immunology)
• Male
• Mice
• Mucous Membrane (immunology)
• Organic Chemicals (administration & dosage, chemistry, immunology)
• Oryza (chemistry)
• Pepsin A (chemistry)
• Plants, Genetically Modified
• Pollen (immunology)
• Protein Stability
• Proteolysis
• Recombinant Proteins (metabolism)
• Rhinitis, Allergic, Seasonal (immunology, therapy)
• Seeds (chemistry)
• Vaccines (immunology)