Oral Immunotherapy for Allergic Conjunctivitis Using Transgenic Rice Expressing Hypoallergenic Antigens

Oral immunotherapy with enteric-coated capsules for allergic rhinitis caused by house dust mites

Background

Oral immunotherapy (OIT) is a promising allergen-specific approach in the management of food allergy; however, studies on OIT for allergic rhinitis (AR) have rarely been reported. The purpose of this study is to evaluate the efficacy and safety of OIT using enteric-coated capsules for AR induced by house dust mites.

Methods

A total of 49 patients with AR were enrolled, including 25 who received subcutaneous immunotherapy (SCIT) and 24 who received OIT. The clinical efficacy and safety in both groups were evaluated.

Results

After 1 year of treatment, both SCIT and OIT demonstrated significant therapeutic effects. OIT was found to be more effective than SCIT in reducing the total AR symptom score and improving the results of nasal provocation tests. Local and systemic adverse reactions were observed in the SCIT group, while none were reported in the OIT group.

Conclusion

OIT is an effective and safe treatment for mite-induced AR.

Protein and Antibody Engineering: Suppressing Degranulation of the Mast Cells and Type I Hypersensitivity Reaction

With an increase in atopic cases and owing to a significant role of mast cells in type I hypersensitivity, a therapeutic need to inhibit degranulation of mast cells has risen. Mast cells are notorious for IgE-mediated allergic response. Advancements have allowed researchers to improve clinical outcomes of already available therapies. Engineered peptides and antibodies can be easily manipulated to attain desired characteristics as per the biological environment. A number of these molecules are designed to target mast cells in order to regulate the release of histamine and other mediators, thereby controlling type I hypersensitivity response. The aim of this review paper is to highlight some of the significant molecules designed for the purpose.

Oral delivery of therapeutic proteins bioencapsulated in plant cells: preclinical and clinical advances

Oral delivery of protein drugs (PDs) made in plant cells could revolutionize current approaches of their production and delivery. Expression of PDs reduces their production cost by elimination of prohibitively expensive fermentation, purification, cold transportation/storage, and sterile injections and increases their shelf life for several years. Ability of plant cell wall to protect PDs from digestive acids/enzymes, commensal bacteria to release PDs in gut lumen after lysis of plant cell wall and role of GALT in inducing tolerance facilitate prevention or treatment allergic, autoimmune diseases or anti-drug antibody responses. Delivery of functional proteins facilitate treatment of inherited or metabolic disorders. Recent advances in making PDs free of antibiotic resistance genes in edible plant cells, long-term storage at ambient temperature maintaining their efficacy, production in cGMP facilities, IND enabling studies for clinical advancement and FDA approval of orally delivered PDs augur well for advancing this novel drug delivery platform technology.

Distribution of serum specific IgE in children with allergic conjunctivitis and analysis of its concomitant allergic diseases

BACKGROUND

Allergic conjunctivitis (AC) is predominantly caused by serum specific-IgE (sIgE)-mediated type I allergy. This study aims to analyze the distribution of sIgE in children with AC, and the concomitant allergic diseases.

METHODS

The clinical data from 310 children, diagnosed with AC and admitted to our hospital from January 2017 to January 2019 were retrospectively collected. The children were divided into three groups: infant group (2 months to 1 year old, 91 cases), child group (1 to 3 years old, 112 cases), and preschool group (3 to 6 years old, 107 cases). Children in every group were analyzed for positive rates, the number of positive sIgE types, the distribution of positive inhaling and ingesting allergens and concomitant allergic diseases.

RESULTS

The sIgE positive rate of infant was significantly lower than that of the other two groups, and the number of 18.75% sIgE positive species was 1. The number of sIgE positive species in the child group and preschool group was more than 2 (78.30%, 71.15%). The positive rate of sIgE to dust mites, house dust, animal dander, eggs, beef, mutton and mango in the preschool group was significantly higher than the other groups (P<0.05). The positive rate of sIgE to milk in infant group was significantly higher than the other two groups (P<0.05). Children in the preschool group showed the highest incidence of AC, AC + allergic rhinitis, AC + allergic rhinitis + wheezing, while those in the infant group displayed the lowest incidence (P<0.05). AC + gastrointestinal allergy, AC + atopic dermatitis, AC + gastrointestinal allergy + atopic dermatitis in infant group was significantly higher than the other two groups (P<0.05). Patients in the child group displayed a significantly higher incidence of AC + infant wheezing than the other two groups (P<0.05).

CONCLUSIONS

We correlated children's age with the positive rate and gradual increase in types of AC allergens. Concomitant allergic diseases of children with AC at different ages conform to the natural course of allergic diseases. In clinic, improving the diagnostic efficiency of AC in children, and early interventional treatment will positively contribute to their prognosis, and reduce the risk of other allergic diseases.

T-cell activation by transgenic rice seeds expressing the genetically modified Japanese cedar pollen allergens

Transgenic rice seeds that contain genetically modified Cry j 1 and Cry j 2, the two major allergens of Cryptomeria japonica (Japanese cedar; JC), have been developed as immunotherapeutic candidates for JC pollinosis. Because the transgenic rice (TG-rice) seeds express allergens containing whole amino acid sequences of Cry j 1 and Cry j 2 in the endosperm tissue (edible part of rice grain), they can potentially target all Cry j 1- and Cry j 2-specific T-cells. However, it was unknown whether antigenicity of Cry j 1 and Cry j 2 could be completely preserved in TG-rice seeds. We verified the antigenicity of TG-rice seeds to T-cells through the analysis of the proliferative responses of T-cells in Cry j 1- or Cry j 2-immunized mice or T-cell lines to TG-rice seed extract. First, four mouse strains were immunized with Cry j 1 or Cry j 2. T-cells in the immunized mice proliferated on treatment with TG-rice seed extract, but not non-transgenic wild-type rice (WT-rice) seed extract. Furthermore, T-cell lines were established from the spleen cells of the immunized mice. Each T-cell line resulted in a proliferative response to TG-rice seed extract, but not to WT-rice seed extract, suggesting that TG-rice seeds certainly express T-cell epitopes corresponding to T-cell lines. Considering the modified amino acid sequences of Cry j 1 and Cry j 2 in TG-rice seeds, the expression of specific T-cell epitopes suggested that TG-rice seeds express all possible T-cell epitope repertoires of Cry j 1 and Cry j 2.