Suppression of collagen‐induced arthritis by oral administration of transgenic rice seeds expressing altered peptide ligands of type II collagen

• Published in: Plant biotechnology journal 2014-10, Vol.12 (8), p.1143-1152
• Main Authors: Iizuka, Mana, Wakasa, Yuhya, Tsuboi, Hiroto, Asashima, Hiromitsu, Hirota, Tomoya, Kondo, Yuya, Matsumoto, Isao, Takaiwa, Fumio, Sumida, Takayuki
• Format: Article
• Language: English
• Subjects: Administration, Oral; altered peptide ligands; Animal models; Animals; Antibodies; Antigens; APL (programming language); Arthritis; Arthritis, Experimental - chemically induced; Arthritis, Experimental - drug therapy; Arthritis, Rheumatoid - chemically induced; Arthritis, Rheumatoid - drug therapy; Autoimmune diseases; CD25 antigen; CD4 antigen; Collagen; Collagen (type II); Collagen Type II - genetics; Collagen Type II - metabolism; Collagen Type II - therapeutic use; Collagens; Cytokines - metabolism; Disease Models, Animal; Endosperm; Foxp3 protein; Genes; Glutelin; glutelins; Health services; Herbicides; Humans; Immunization; Immunotherapy; interferon-gamma; interleukin-2; Interleukins; Joint diseases; Ligands; Lymph nodes; Lymphocytes; Lymphocytes T; Mice; Mice, Inbred DBA; Oral administration; Oryza - genetics; Oryza - metabolism; Oryza sativa; Peptides; Peptides - genetics; Peptides - immunology; Peptides - metabolism; Plants, Genetically Modified; Proteins; Rheumatoid arthritis; Rice; Seeds; Splenocytes; T-lymphocytes; therapeutics; Transcription factors; Transgenes; Transgenic; transgenic plants; transgenic rice seed; type II collagen; Vaccines; Vacuoles; γ-Interferon
• ISSN: 1467-7644; 1467-7652
• DOI: 10.1111/pbi.12223

Rheumatoid arthritis (RA) is an autoimmune disease associated with the recognition of self proteins secluded in arthritic joints. We previously reported that altered peptide ligands (APLs) of type II collagen (CII256‐271) suppress the development of collagen‐induced arthritis (CIA). In this study, we generated transgenic rice expressing CII256‐271 and APL6 contained in fusion proteins with the rice storage protein glutelin in the seed endosperm. These transgene products successfully and stably accumulated at high levels (7–24 mg/g seeds) in protein storage vacuoles (PB‐II) of mature seeds. We examined the efficacy of these transgenic rice seeds by performing oral administration of the seeds to CIA model mice that had been immunized with CII. Treatment with APL6 transgenic rice for 14 days significantly inhibited the development of arthritis (based on clinical score) and delayed disease onset during the early phase of arthritis. These effects were mediated by the induction of IL‐10 from CD4⁺ CD25⁻ T cells against CII antigen in splenocytes and inguinal lymph nodes (iLNs), and treatment of APL had no effect on the production of IFN‐γ, IL‐17, IL‐2 or Foxp3⁺ Treg cells. These findings suggest that abnormal immune suppressive mechanisms are involved in the therapeutic effect of rice‐based oral vaccine expressing high levels of APLs of type II collagen on the autoimmune disease CIA, suggesting that the seed‐based mucosal vaccine against CIA functions via a unique mechanism.