Immunological parameters associated with the development of allergic rhinitis: a preliminary prospective study.

BACKGROUND: Many subjects are sensitized to Japanese cedar pollen but do not develop allergic rhinitis (AR). The aim of this study was to examine the immunologic parameters related to the development of AR in sensitized subjects. METHODS: The subjects were 33 adults who were sensitized to Japanese cedar pollen, but had not developed as of 2007. Cedar pollen-specific IgE (sIgE) and total IgE (tIgE) in serum, cedar pollen antigen (Cry j 1) Cry j-specific memory Th2 cell clone size, and the Cry j-specific induced regulatory T cell (iTreg) level were examined before and after the season in 2008. RESULTS: Eight of the 33 subjects developed cedar pollinosis. The sIgE titers before the season in these eight subjects did not differ from those in the subjects who did not develop pollinosis, but the titers after the season were significantly higher in the group that developed pollinosis. The sIgE/tIgE ratio increased in almost all subjects, but the ratio was significantly higher before the season in the subjects who developed pollinosis. Cry j-specific Th2 cells were detected in all subjects, but the clone size only increased in those that developed pollinosis. The Cry j-specific iTreg population did not differ between the two groups. CONCLUSION: A high sIgE/tIgE ratio before the season may be predictive of development of pollinosis, and an increase in the allergen-specific Th2 clone size during the pollen season could be a biomarker for pollinosis. The role of allergen-specific iTreg cells in the development of pollinosis could not be clarified in this preliminary study.

Sublingual administration of Lactobacillus paracasei KW3110 inhibits Th2-dependent allergic responses via upregulation of PD-L2 on dendritic cells.

Lactic acid bacteria have potential in immunomodulation therapy, but their clinical efficacy and underlying mechanisms are unclear. We aimed to clarify the anti-allergic immune responses induced by intragastric and sublingual administration of heat-killed Lactobacillus paracasei KW3110 and Lactobacillus acidophilus L-92. The KW3110 strain (but not the L-92 strain) enhanced ovalbumin (OVA)-induced expression of CCR-7 and PD-L2 in murine dendritic cells (DCs), and strongly inhibited IL-5 and IL-13 production in vitro in co-cultures with Th2-skewed CD4(+) T cells from DO11.10 transgenic mice. Sublingual administration of low-dose KW3110 (but not L-92) to OVA-sensitized mice selectively suppressed serum IgE production and Th2 cytokine expression in cervical lymph nodes, and significantly improved symptoms after OVA provocation in vivo. KW3110 probably accelerates DC migration into the regional lymph nodes and inhibits Th2 cytokine production through enhanced CCR-7 and PD-L2 expression. Thus, sublingual KW3110 administration may be effective in reducing allergic inflammation.

Nasal submucosal administration of antigen-presenting cells induces effective immunological responses in cancer immunotherapy.

Human NKT cells are known to have strong antitumor activities and to be activated by specific ligand, α-galactosylceramide (αGelCer). We examined the migration pattern of αGalCer-pulsed DCs and the immune responses after administration by different routes. DCs injected into nasal submucosa quickly migrated to the lateral neck lymph rather than the lateral lymph nodes. The absolute number of NKT cells and the IFN-γ-producing cells increased in peripheral blood after injection of the DCs into nasal submucosa. We conducted a phase I study with αGalCer-pulsed DCs administered in nasal submucosa of patients with head and neck cancer, and evaluated safety and feasibility. The results showed that nasal submucosal administration of α-GalCer-pulsed DCs was safe and a smaller number of these DCs could exhibit significant immune responses and some positive clinical effects. In additional study, the use of the intra-arterial infusion of activated NKT cells and the submucosal injection of α-GalCer-pulsed DCs has been shown to induce significant antitumor immunity and had beneficial clinical effects in the management of advanced head and neck squamous cell carcinoma. The NKT cell-based cancer immunotherapy may be helpful in management of head and neck cancer and needs to be explored in further detail.

A randomized controlled trial of sublingual immunotherapy for Japanese cedar pollinosis.

BACKGROUND: Japanese cedar pollen represents an important and unique allergen. Sublingual immunotherapy (SLIT) has been suggested to be a highly effective route of desensitization against a variety of allergens. However, little information is available about its use in cedar pollen allergy. METHODS: A blinded randomized, placebo-controlled trial employing SLIT for cedar pollinosis was conducted over a period of 6 months. Sixty-seven subjects were enrolled and the symptom scores during the pollen season were evaluated by a symptom diary, measurement of cedar-specific IgE and IgG4, and determination of Cry j-specific Th2 clones before SLIT and before and after the pollen season. RESULTS: No major adverse effects were observed in either group. The serum-specific IgG4 activity increased significantly after SLIT in the active group. The active group also exhibited significantly lower symptom scores compared to the placebo. The specific Th2 clone sizes were not significantly different between the groups before the pollen season. However, an increase in the clone size was observed after the pollen season in the placebo group, but not in the active group. CONCLUSION: Use of SLIT for Japanese cedar pollinosis was found to be safe and associated with an increase in cedar-specific IgG4 levels. Such therapy inhibited the increase in Cry j-specific Th2 clone size induced by pollen exposure. Finally, use of SLIT resulted in significant improvement of the clinical symptoms of cedar pollinosis in this patient population. These observations suggest that SLIT may offer another safe approach to the management of cedar pollinosis.

Migration of tumor antigen-pulsed dendritic cells after mucosal administration in the human upper respiratory tract.

Tumor-specific peptide-pulsed dendritic cells (DC) were administered via different routes to a group of patients with head and neck cancers. The migration and homing patterns of such antigen-stimulated cells was carefully studied employing single photon emission computed tomography (SPECT). The DC administered directly into the nasal submucosa quickly migrated very rapidly to the regional neck lymph nodes in the neck. However, after inoculation of the cells into the palatine tonsils, the DCs remained close to the site of administration and did not migrate to the regional lymph nodes or to other mucosal regions. After nasal submucosal administration of the DC, tumor-antigen-specific cytotoxic T cells were detected in the ipsilaterals but not in the contra lateral lymph nodes. These results suggest that after antigen processing, the regional lymph nodes serve as inductive sites for development of mucosal immune responses and for induction of memory cells during the local immunological responses in the nasopharyngeal-associated lymphoid tissue in man.