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Summary Background Tiotropium bromide, a long acting muscarinic receptor inhibitor, is a potent agent for patients with bronchial asthma as well as chronic obstructive pulmonary disease. Objective The aim of this study was to evaluate whether tiotropium bromide can inhibit allergen-induced acute and chronic airway inflammation, T helper (Th)2 cytokine production, and airway remodelling in a murine model of asthma. Methods Balb/c mice were sensitized and challenged acutely or chronically to ovalbumin (OVA). The impact of tiotropium bromide was assessed using these mice models by histologic, morphometric, and molecular techniques. Moreover, the effect of tiotropium bromide on Th2 cytokine production from purified human peripheral blood mononuclear cells (PBMCs) was assessed. Results Treatment with tiotropium bromide significantly reduced airway inflammation and the Th2 cytokine production in bronchoalveolar lavage fluid (BALF) in both acute and chronic models of asthma. The levels of TGF-β1 were also reduced by tiotropium bromide in BALF in a chronic model. The goblet cell metaplasia, thickness of airway smooth muscle, and airway fibrosis were all significantly decreased in tiotropium bromide-treated mice. Moreover, airway hyperresponsiveness (AHR) to serotonin was significantly abrogated by tiotropium bromide in a chronic model. Th2 cytokine production from spleen cells isolated from OVA-sensitized mice was also significantly inhibited by tiotropium bromide and 4-diphenylacetoxy-N-methylpiperidine methiodide, which is a selective antagonist to the M3 receptor. Finally, treatment with tiotropium bromide inhibited the Th2 cytokine production from PBMCs. Conclusion These results indicate that tiotropium bromide can inhibit Th2 cytokine production and airway inflammation, and thus may reduce airway remodelling and AHR in a murine model of asthma. Cite this as: S. Ohta, N. Oda, T. Yokoe, A. Tanaka, Y. Yamamoto, Y. Watanabe, K. Minoguchi, T. Ohnishi, T. Hirose, H. Nagase, K. Ohta and M. Adachi, Clinical & Experimental Allergy, 2010 (40) 1266–1275.

Silent brain infarction (SBI) and increased levels of soluble CD40 ligand (sCD40L) and soluble P-selectin (sP-selectin) are associated with an increased risk of cerebrovascular disease.The aim of this study was to evaluate whether SBI and serum levels of sCD40L and sP-selectin are increased in patients with obstructive sleep apnea (OSA).SBI was studied by brain magnetic resonance images in 50 male patients with OSA and 15 obese male control subjects who were free of comorbidities. In addition, the effects of 3 months of treatment with nasal continuous positive airway pressure (nCPAP) on serum parameters were studied in 24 patients with moderate to severe OSA.The percentage of SBI in patients with moderate to severe OSA (25.0%) was higher than that of obese control subjects (6.7%) or patients with mild OSA (7.7%). Serum levels of sCD40L and sP-selectin were significantly higher in patients with moderate to severe OSA than in obese control subjects (p0.05) or patients with mild OSA (p0.05). In addition, nCPAP significantly decreased serum levels of sCD40L (p0.03) and sP-selectin (p0.01) in patients with moderate to severe OSA.These results suggest that serum levels of sCD40L and sP-selectin are elevated and SBI is more common in patients with moderate to severe OSA, leading to elevated cerebrovascular morbidity. Moreover, nCPAP may be useful for decreasing risk in patients with moderate to severe OSA.

Increased carotid intima-media thickness (IMT) and increased serum levels of inflammatory markers, such as C-reactive protein (CRP), interleukin (IL)-6, and IL-18, are associated with an increased risk of cardiovascular and cerebrovascular diseases. The aim of this study was to evaluate whether carotid IMT, a useful marker for early atherosclerosis, is associated with these inflammatory markers in patients with obstructive sleep apnea (OSA). Carotid IMT was investigated with ultrasonography in 36 patients with OSA and 16 obese control subjects. Serum levels of CRP, IL-6, and IL-18 were measured at 5:00 A.M. Carotid IMT (p < 0.001) and serum levels of CRP (p < 0.003), IL-6 (p < 0.005), and IL-18 (p < 0.03) of patients with OSA were significantly higher than those of obese control subjects. Carotid IMT was significantly correlated with serum levels of CRP (r = 0.61, p = 0.0001), IL-6 (r = 0.41, p = 0.01), and IL-18 (r = 0.45, p = 0.005), duration of OSA-related hypoxia (r = 0.60, p = 0.0001), and severity of OSA (r = 0.50, p = 0.002). In addition, the primary factor influencing carotid IMT was duration of hypoxia during total sleep time (p = 0.036). These results suggest that OSA-related hypoxia and systemic inflammation might be associated with the progression of atherosclerosis and thus might increase the risks of cardiovascular and cerebrovascular morbidity in patients with OSA.

Interleukin (IL)-17F is a recently described human cytokine belonging to the IL-17 gene family, but its in vivo function remains to be determined. To this end, a full-length mouse IL-17F cDNA sequence with a 483-bp coding region sequence was first identified. Pulmonary gene transfer of an IL-17F expression construct (pcDNAmIL-17F) in mice was used to investigate its regulatory role. The results showed first that a significant increase in the number of neutrophils was seen in the bronchoalveolar lavage fluids of IL-17F-transduced mice, concomitant with increased expression of genes encoding C-X-C chemokines and inflammatory cytokines when compared with mock and phosphate-buffered saline control animals. Mucosal transfer of the IL-17F gene in ovalbumin (OVA)-sensitized mice before antigen (Ag) challenge enhanced the levels of Ag-induced pulmonary neutrophilia, but not eosinophilia, goblet cell hyperplasia, and mucin gene expression. However, no significant change in the levels of Th2 cytokine expression was noted. A significant enhancement of ventilatory timing in response to inhaled methacholine was also seen in IL-17F-transduced, Ag-sensitized mice, whereas a small but significant increase was found in IL-17F-transduced, naive mice. These results suggest a role for IL-17F in the induction of neutrophilia in the lungs and in the exacerbation of Ag-induced pulmonary inflammation.

Interleukin (IL)-12 production and IL-12 receptor (IL-12R) beta2 chain expression were investigated in patients with allergic asthma successfully treated with rush immunotherapy (RIT) and control patients with mild allergic asthma. Peripheral blood mononuclear cells (PBMCs) were stimulated with Dermatophagoides farinae (Der f), and production of cytokines was measured. Furthermore, the effects of cytokines on IL-12R beta2 chain expression on CD4(+) T cells were investigated. Production by PBMCs of IL-12 and IFN-gamma was significantly higher and production of IL-4 was significantly lower after stimulation with Der f allergen in RIT-treated patients than in control patients. Significant increases in the expression of IL-12R beta2 chain before and after stimulation of CD4(+) T cells with IL-12 or IFN-gamma were observed in RIT-treated patients compared with that in control patients. Allergen RIT increases IL-12 production and IL-12R beta2 chain expression and thus may convert cytokine production from Th2 to Th1 or Th0 type in allergic asthma.

Summary Background Suplatast tosilate is an anti-allergic agent that suppresses cytokine production by human Th2 cells. Objective We investigated the effects of suplatast tosilate on the production of thymus- and activation-regulated chemokine (TARC) by T cells from allergic patients with asthma. Methods Purified protein derivative (PPD)-specific Th1 cell lines and Dermatophagoides farinae (Der f)-specific Th2 cell lines were established from nine patients with house dust mite-allergic asthma. The effects of suplatast tosilate on mRNA expression of TARC and protein production of TARC from antigen-specific Th1 or Th2 cell lines were investigated after stimulation with relevant antigens or phytohemagglutinin (PHA). In addition, the effects of IL-4, IL-10, and IFN-γ on TARC production by Der f-specific Th2 cell lines in the presence or absence of suplatast tosilate were studied. Results Although PPD-specific Th1 cell lines did not produce TARC after stimulation with PPD antigen or PHA, stimulation of Der f-specific Th2 cell lines with Der f antigen or PHA increased production of TARC. Suplatast tosilate significantly and dose-dependently inhibited production of TARC by Der f-specific Th2 cell lines stimulated with either Der f antigen (76.5% inhibition at 100 µg/mL, P

Background: Interleukin (IL)–10 induces a long–term antigen–specific anergy in human CD4+ T cells. Methods: Peripheral blood mononuclear cells (PBMCs) were isolated from house dust mite (Dermatophagoides farinae, Der f)–sensitized asthmatic patients. PBMCs were stimulated with Der f antigen for 72 h immediately after purification or after 48 h of resting culture with medium, and IL–10 and IL–5 in the culture supernatant were measured. PBMCs were also stimulated with Der f antigen for 7 days either immediately after purification or after 48 h of resting culture, after which cells were collected. Secondary proliferative responses of these cells to stimulation for 3 days with Der f antigen and mitomycin C–treated PBMCs as antigen–presenting cells or with phorbol myristate acetate (PMA) plus calcium ionophore were investigated. Results: Stimulation of PBMCs with Der f antigen immediately after purification significantly increased the proliferative response and IL–5 production. Stimulation of PBMCs with Der f antigen after resting culture with medium alone for 48 h significantly decreased IL–5 production and markedly increased IL–10 production. Although activation of cells with Der f antigen immediately after purification significantly increased secondary proliferative responses, stimulation after 48 h of resting culture failed to increase secondary proliferative responses. However, proliferation recovered when cells were activated with PMA plus calcium ionophore. Conclusion: These results suggest that antigen–specific Th2 cells are anergized by IL–10 and that Th2 cell tolerance may suppress eosinophilic inflammation in allergic asthma.