Immunological effects of sublingual immunotherapy with Japanese cedar pollen extract in patients with combined Japanese cedar and Japanese cypress pollinosis

Real-world efficacy of sublingual immunotherapy with Japanese cedar pollen for cypress pollinosis

Background

It remains unclear whether allergen immunotherapy with Japanese cedar pollen extract is effective for Japanese cypress pollinosis in real-world settings.

Objective

We sought to investigate the Japan-wide prevalence of cypress pollinosis, the efficacy of cedar sublingual immunotherapy (SLIT) on cypress pollinosis, the role of serum-specific IgE levels in pollinosis, and patients' interest in the development of cypress SLIT.

Methods

A cross-sectional, multicenter study using self-administered questionnaires was conducted in regions of Japan where cedar and cypress pollen dispersals are prevalent. This study included patients aged 5 to 69 years who received cedar SLIT in 2023.

Results

Of 2597 participants analyzed, 84.5% experienced pollinosis symptoms during the cypress season before receiving cedar SLIT. Among these patients, 40.2% felt that cedar SLIT was less effective during the cypress season than during the cedar season. The longer the patients received cedar SLIT, the greater the inefficacy perceived during the cypress versus the cedar season. In the symptomatic patients, serum IgE levels were significantly higher for cedar and cypress as compared with those observed in subjects without symptoms during the cypress season. No significant differences were reported in IgE levels for cedar and cypress between patients reporting either high or lower efficacy for the cedar SLIT during cypress season. Interest in cypress SLIT was seen in 78.4% of these patients.

Conclusions

Although there is a bias based on regional distribution, cedar SLIT has induced a limited efficacy on cypress pollinosis in real-world settings, suggesting a need for the development of cypress SLIT.

Cha o 3, a cypress pollen allergen, does not activate basophils in Japanese cypress pollinosis

Background

In Japan, pollinosis caused by the Japanese cypress (JCy) Chamaecyparis obtusa is among the very common seasonal allergies. In JCy pollinosis, Cha o 1 is the first major allergen, and Cha o 2 is the second major allergen. Recently, Cha o 3 was identified as a new JCy pollen allergen in JCy pollinosis. However, the relative contribution of Cha o 3 to JCy pollinosis compared with that of Cha o 1 and that of Cha o 2 has not been fully elucidated.

Objective

This study aimed to clarify the allergenicity of Cha o 3 compared with that of Cha o 1 and Cha o 2 in JCy pollinosis.

Methods

We recruited 27 patients with JCy pollinosis and performed the basophil activation test (BAT) with native (n) Cha o 1, Cha o 2, and Cha o 3 purified from JCy pollen. In addition, we a performed JCy-specific IgE suppression test.

Results

In the BAT, 26 of 27 patients (96%) and 18 of 27 patients (67%) showed positive basophil activation in response to n Cha o 1 and n Cha o 2, respectively, as judged by CD203c expression. Little CD203c expression in response to n Cha o 3 was seen. The presence of n Cha o 3 marginally reduced the titer levels of JCy-specific IgE.

Conclusion

Cha o 3 showed little ability to activate basophils and suppress JCy-specific IgE titers compared with Cha o 1 or Cha o 2 in patients with JCy pollinosis. Thus, Cha o 3 may not be a major allergen in JCy pollinosis.

Potential Effects of AIT on Nonspecific Allergic Immune Responses or Symptoms

Allergen immunotherapy (AIT) is a treatment in which clinically corresponding allergens are administered to patients with allergic diseases, either by subcutaneous immunotherapy (SCIT) or sublingual immunotherapy (SLIT), or by oral immunotherapy (OIT) in the case of food allergy. Since etiological allergens are administered to patients, AIT is presumed to modify mainly allergen-specific immune responses. In bronchial asthma, AIT with house dust mites (HDM) alleviates clinical symptoms, suppresses airway hyperresponsiveness, and reduces medication doses of HDM-sensitive asthmatics. Moreover, AIT can suppress the symptoms of other allergic diseases associated with asthma including allergic rhinitis. However, AIT sometimes reduces allergic symptoms not induced by the responsible allergens, such as non-targeted allergens, in clinical settings. Furthermore, AIT can suppress the spread of sensitization to new allergens that are not targeted allergens by AIT, suggesting the suppression of allergic immune responses in an allergen-nonspecific manner. In this review, the nonspecific suppression of allergic immune responses by AIT is discussed. AIT has been reported to increase regulatory T cells that produce IL-10, transforming growth factor-β, and IL-35, IL-10-producing regulatory B cells, and IL-10-producing innate lymphoid cells. These cells can suppress type-2 mediated immune responses mainly through the production of anti-inflammatory cytokines or a cell-cell contact mechanism, which may be involved in the nonspecific suppression of allergic immune responses by AIT.

Effects of a Cloth Panel Containing a Specific Ore Powder on Patients with Chamaecyparis obtusa (Cypress) Pollen Allergy

Pollen allergy to Japanese cedar and cypress is a serious illness that impairs daily life and sleep, especially during pollen season. We have reported that placing a cloth panel containing a specific natural ore powder (CCSNOP) in a room may alleviate the symptoms of hay fever and may also benefit the immune system. This ore is from the Aso mountain range, a volcano on Kyushu Island in the southwestern part of Japan. The purpose of this study was to verify the effect of CCSNOP on cypress pollen. Thirty-one double-blind tests, which investigated cedar pollen allergies, were conducted from February to March 2018 and have already been reported. After this, in early April, 10 of these cases were recruited and all had CCSNOP installed in their bedrooms. Before that, various symptoms and changes in medication were recorded in a “Symptom Diary” and included a mood survey by a questionnaire, stress test using saliva amylase, changes in cypress-specific immunoglobulins IgE and IgG4 by blood sampling, and eosinophil changes. In addition, changes in 29 types of cytokines were investigated. Exposure to CCSNOP relieved symptoms and subjects decreased their intake of medication. There was no change in mood or stress, but eosinophil levels tended to decrease. Although there were no statistical changes in cypress-specific IgE or IgG4, an increase in the former and a decrease in the latter were observed in some individuals during the period of pollen dispersal. Furthermore, levels of GM-CSF and IL8 decreased significantly after use of CCSNOP. The CCSNOP was shown to be effective against cypress pollen allergy, and future investigations will be necessary to observe the long-term effects of CCSNOP.

Serum Concentrations of Antigen-Specific IgG4 in Patients with Japanese Cedar Pollinosis

Purpose: To elucidate the usefulness of Japanese cedar pollen (JCP)-specific antigen-specific immunoglobulin (IgG) 4 as a biomarker for predicting the efficacy of sublingual immunotherapy for cedar pollen-induced allergic rhinitis. Methods: We divided a total of 105 cases with Japanese cedar pollinosis into three groups: “SLIT Successful,” SLIT Unsatisfactory,” and “SCIT” groups. The SLIT group patients were treated with JCP Droplet (Torii Pharmaceutical Co. Ltd., Tokyo, Japan) for one year from 2015 and were divided into two groups, the SLIT Successful group or the SLIT Unsatisfactory group. The SLIT Successful group (n = 16) were subjects treated by SLIT only, who were able to experience control of their naso-ocular symptoms without the need for antiallergic rescue agents during the peak season of atmospheric pollen. The SLIT Unsatisfactory group (n = 76) comprised subjects treated with SLIT only, who did not respond successfully, and were administered with rescue agents to control their naso-ocular symptoms. The SCIT group had been treated with standardized JCP extract (Torii Pharmaceutical Co., Ltd., Tokyo, Japan) for three years from 2012, and were also able to experience control of their symptoms during the peak pollen season without the need for antiallergic rescue agents. We determined the serum level of JCP-specific immunoglobulin E (IgE), IgG, and IgG4 used in the 3gAllergy-specific IgE assay (3gAllergy). The serum levels of periostin and SCCA2 were measured using established ELISA procedures (clones SS18A and SS17B; Shino-Test, Japan) following the manufacturer’s instructions. We then made ROC curves for each group and assessed which index was best able to predict the efficacy of sublingual immunotherapy. Results: Serum JCP-specific IgE was significantly lower in the SCIT group than in the SLIT Successful group and the SLIT Unsatisfactory group (p < 0.05). Serum JCP-specific IgG was significantly higher in the SCIT group and the SLIT Successful group than in the SLIT Unsatisfactory group (p < 0.05). Serum JCP-specific IgG4 was also significantly higher in the SCIT group and the SLIT Successful group than in the SLIT Unsatisfactory group (p < 0.05). There was no significant difference among serum levels of periostin in the SCIT group, the SLIT Successful group, or the SLIT Unsatisfactory group. There was also no significant difference in SCCA2 among the three groups. In terms of ROC curves, a serum JCP-specific IgG4 value greater than 989.5 UA/mL showed the best sensitivity (93.3%) and specificity (94.7%) (p < 0.05) among other parameters. Conclusions: The serum JCP-specific IgG4 level is significantly correlated with the clinical efficacy of SLIT. Serum JCP-specific IgG4 cutoff levels greater than 989.5 UA/mL were correlated with an effective clinical response to SLIT, with a sensitivity of 93.3% and a specificity of 94.7%.

Japanese cedar and cypress pollinosis updated: New allergens, cross-reactivity, and treatment

Pollen from many tree species in the Cupressaceae family is a well-known cause of seasonal allergic diseases worldwide. Japanese cedar pollinosis and Japanese cypress pollinosis, which are caused by pollen from Japanese cedar (Cryptomeria japonica) and Japanese cypress (Chamaecyparis obtusa), respectively, are the most prevalent seasonal allergic diseases in Japan. Recently, the novel major Japanese cypress allergen Cha o 3 and the homologous Japanese cedar allergen Cry j cellulase were identified, and it was shown, for the first time, that cellulase in plants is allergenic. Although the allergenic components of pollen from both species exhibit high amino acid sequence identity, their pollinosis responded differently to allergen-specific immunotherapy (ASIT) using a standardized extract of Japanese cedar pollen. Pharmacotherapy and ASIT for Japanese cedar and cypress pollinosis have advanced considerably in recent years. In particular, Japanese cedar ASIT has entered a new phase, primarily in response to the generation of updated efficacy data and the development of new formulations. In this review, we focus on both Japanese cypress and cedar pollinosis, and discuss the latest findings, newly identified causative allergens, and new treatments. To manage pollinosis symptoms during spring effectively, ASIT for both Japanese cedar and Japanese cypress pollen is considered necessary.

Sublingual immunotherapy for 4 years increased the number of Foxp3+ Treg cells, which correlated with clinical effects

OBJECTIVE

At least 3 years of sublingual immunotherapy (SLIT) is required to achieve long-term clinical tolerance for allergens. However, immunological changes with more than 3 years of SLIT have not yet been elucidated in detail. The present study investigated whether the numbers of regulatory T (Treg) cells and regulatory B (Breg) cells increased with 4 years of SLIT and if these increases correlated with clinical effects for pollinosis.

METHODS

Seven Japanese cedar pollinosis patients received SLIT in 2014 or 2015 and continued treatment until May 2019. In May 2017 and May 2019, peripheral blood mononuclear cells (PBMCs) were collected from the patients, and analyzed by flow cytometer.

RESULTS

(1) The visual analogue scale (VAS) was significantly higher in 2019 than in 2017. (2) The percentages of Foxp3⁺ Treg cells, type 1 regulatory T (Tr1) cells, and Breg cells in PBMCs were significantly higher in 2019 than in 2017. (3) The percentage of Foxp3⁺ Treg cells in PBMCs positively correlated with VAS, whereas those of Tr1 cells and Breg cells did not.

CONCLUSIONS

These results suggest that 4 years of SLIT is needed to achieve sustained increases in Foxp3⁺ Treg cells, which are closely associated with the efficacy of SLIT.