Serum IL-9 levels depend on allergen exposure: preliminary study.

BACKGROUND: Th9 is a new T cell subset characterized by interleukin 9 (IL-9) production. Serum IL-9 levels are related to symptom severity in patients with allergic rhinitis (AR). This study aimed at investigating whether IL-9 may depend on allergen exposure. METHODS: 35 AR patients (16 males, mean age 33.2 years) with monosensitization to Parietaria were studied when symptomatic; 38 AR patients (22 males, mean age 30.9 years) with monosensitization to birch were recruited at the same time, but were symptom free. Serum IL-9 was assayed in all patients. RESULTS: Patients with Parietaria allergy and exposed to allergen had higher serum IL-9 levels than patients with birch allergy and not exposed to allergen (p<0.05). CONCLUSIONS: This preliminary study shows that serum IL-9 levels may depend on allergen exposure: symptomatic patients with pollen-induced AR, evaluated during the pollen season, have higher values than patients studied outside the pollen season and without symptoms.

Sublingual immunotherapy may affect serum neopterin: preliminary findings.

BACKGROUND: Neopterin is a protein produced by monocytes/macrophages. It has been considered a biomarker of immune activation in several disorders. However, there are few studies in allergic rhinitis (AR). This study evaluated the serum neopterin levels in patients with pollen-induced AR or treated with sublingual immunotherapy (SLIT) and in healthy subjects. METHODS: 146 subjects (70 males, median age 30.5 years): 56 with moderate-severe persistent AR, 40 with AR and successfully treated with 2 year SLIT, and 50 healthy controls were consecutively evaluated outside the pollen season. A skin prick test and blood sampling for assessing serum neopterin levels were performed in all subjects. RESULTS: SLIT-treated patients had lower neopterin levels than untreated patients and healthy subjects (respectively p=0.012 and p=0.0001). CONCLUSIONS: Neopterin is a biomarker for immune activation, SLIT may affect serum neopterin probably as a consequence of Treg response to SLIT.

Tryptophan metabolism in allergic rhinitis: the effect of pollen allergen exposure.

This study evaluates serum tryptophan, kynurenine, kynurenine-to-tryptophan ratio, and neopterin levels in patients with pollen-induced allergic rhinitis (AR) during and outside of the pollen season, along with these values in healthy subjects. A total of 102 patients (56 female and 46 male, median age 28.7 years) were included in this study: 56 with seasonal AR evaluated outside of the pollen season and thus without allergic inflammation and symptoms, and 46 with seasonal AR evaluated during the pollen season with symptoms. A skin prick test and blood sampling for assessing serum concentrations of tryptophan and kynurenine and of immune activation marker neopterin were performed in all subjects. Tryptophan and kynurenine serum concentrations were higher in AR patients than in controls and were also higher out of pollen season than during this season. In conclusion, this preliminary study demonstrates that serum tryptophan metabolism could serve as a biomarker in patients with AR.

Serum adiponectin levels in patients with seasonal allergic rhinitis.

BACKGROUND: A few studies have outlined a possible relationship between an increased body mass index and allergic rhinitis. A single study reported that males with seasonal allergic rhinitis (SAR), evaluated outside the pollen season, had increased serum adiponectin levels. OBJECTIVE: The aim of this preliminary study was to evaluate the serum adiponectin levels in a cohort of SAR normo-weight patients evaluated during the pollen season, comparing them with SAR patients evaluated out of pollen season and a group of healthy controls. METHODS: The study included 137 subjects; 62 SAR patients evaluated in their pollen season, while symptomatic, 41 SAR patients studied out their pollen season, while they were without symptoms, and 34 normal subjects. All subjects were consecutively evaluated. All of them were normo-weight. A skin prick test and blood sampling for assessing serum adiponectin levels were performed in all subjects. RESULTS: After analysing genders separately, symptomatic male patients had significantly higher levels than both symptomless and normal males (p=0.0041 and 0.0001 respectively), symptomatic female patients showed significantly higher levels than both symptomless and normal females (p=0.0001 and 0.0071 respectively). CONCLUSION: This study provides the preliminary evidence that adiponectin serum levels might depend on allergen exposure in SAR normo-weight patients.

Serum transforming growth factor-beta levels depend on allergen exposure in allergic rhinitis.

BACKGROUND: Allergic rhinitis (AR) is characterized by inflammation sustained by dysregulated immune response. T-regulatory cells are involved in AR pathogenesis, mainly producing IL-10 and transforming growth factor (TGF)-beta. Indeed, there is a functional and allergen-specific defect of T-regulatory cells in AR. However, there are no data about the influence of allergen exposure on TGF-beta serum levels. Therefore, the aim of this preliminary study was to evaluate TGF-beta serum levels in patients with seasonal AR. Patients were evaluated either outside the pollen season and after 1 preseasonal sublingual immunotherapy (SLIT) course (38 subjects) or during the pollen season (57 subjects). METHODS: All patients were allergic to Parietaria and/or grasses alone. TGF-beta was measured by a commercially available kit. Symptoms, drug use and eosinophils were evaluated.Serum allergen-specific IgG and IgA levels were also measured by the ELISA method. RESULTS: TGF-beta serum levels were significantly lower in patients evaluated outside the pollen season in comparison with the other 2 situations. SLIT induced the significantly highest TGF-beta serum levels. There was a significant negative relationship between TGF-beta and eosinophils in patients after SLIT. IgG and IgA levels were higher in SLIT-treated patients. CONCLUSION: This preliminary study provides evidence that TGF-beta serum levels are significantly dependent on allergen exposure.

Serum leptin levels depend on allergen exposure in patients with seasonal allergic rhinitis.

Several studies have outlined a possible relationship between an increased body mass index (BMI) and respiratory allergic diseases, such as asthma and rhinitis. There are conflicting data about the role for leptin in allergic rhinitis. Therefore, the aim of the study was to evaluate the serum leptin levels in patients with seasonal allergic rhinitis (SAR), enrolled during and outside the pollen season, and in a group of healthy controls. The study included 137 subjects; 62 symptomatic SAR patients evaluated in season, 41 symptomless SAR patients out season, and 34 normal subjects. All subjects were consecutively evaluated. A skin prick test and blood sampling for assessing serum leptin levels were performed in all subjects. After analysing genders separately, symptomatic male patients had significantly higher levels than symptomless and normal subjects (p = 0.0004 and 0.0031 respectively), symptomatic female patients showed significantly higher levels than normal females (p = 0.0002). This study provides the evidence that leptin serum levels depend on allergen exposure in SAR patients.

Serum adipsin levels in patients with seasonal allergic rhinitis: preliminary data.

BACKGROUND: Several studies have outlined a possible relationship between adipokines and respiratory allergic diseases. However, there are no data about a role for adipsin in allergic rhinitis. OBJECTIVE: The aim of the study was to evaluate the serum adipsin levels in patients with seasonal allergic rhinitis (SAR), subdivided into two sub-groups: treated or not treated with sublingual immunotherapy (SLIT), and in a group of healthy controls. METHODS: The study included 110 subjects; i) 24 SLIT-treated SAR patients, ii) 62 untreated SAR patients, and iii) 24 normal subjects. All subjects were consecutively evaluated. A skin prick test and blood sampling for assessing serum adipsin levels were performed in all subjects. RESULTS: Serum adipsin was increased in SAR patients, even though significant only in males. There was also a significant positive association between adipsin and adiponectin. CONCLUSION: This preliminary study reports that adipsin serum levels may be increased in some SAR patients, but further functional studies should be performed.

TGF-beta and IL-17 serum levels and specific immunotherapy.

Two new T cell subsets may be involved in allergic rhinitis (AR) pathogenesis: Th17 and T regulatory cells, mainly producing IL-17 and TGF-beta respectively. Successful Sublingual Immunotherapy (SLIT) induces relevant immunological changes, thus the aim of this study was to evaluate serum IL-17 and TGF-beta levels in AR patients treated with SLIT for 2 years. Patients' blood samples were collected before initiating SLIT (baseline), three months after the end of the first pre-seasonal SLIT course, and at the end of the second pre-seasonal course. IL-17 was detectable only in the most severe allergic patients. SLIT significantly induced an increase in serum TGF-beta levels. There was moreover a significant relationship between TGF-beta and symptom severity and drug use at the end of the study. Therefore, this study provides clinically relevant evidence that two pre-seasonal SLIT courses may significantly affect serum TGF-beta levels.

Two year sublingual immunotherapy affects serum leptin.

BACKGROUND: It has been demonstrated that serum leptin is elevated in females with allergic rhinitis. Recently, it has been reported that one course of sublingual immunotherapy (SLIT) does not affect serum leptin levels. OBJECTIVE: The aim of this study was to evaluate the serum leptin levels in a cohort of patients with pollen-induced allergic rhinitis, before and after two pre-seasonal SLIT courses. METHODS: Forty-one patients (22 males and 19 females, median age 39 years) with AR, due to pollen allergy, and 34 healthy subjects (16 males and 18 females, median age 43 years) were included in the study. Blood sampling for assessing serum leptin was performed in all subjects before and after the second SLIT course. RESULTS: All patients were responders to SLIT. Serum leptin was significantly increased only in males (p=0.0056) after the second SLIT course. CONCLUSION: This preliminary study shows that at least two pre-seasonal SLIT courses were required to induce significant modifications in serum leptin levels, but it occurred only in males. Some hypotheses might be outlined, including a leptin protective effect, however further studies must clarify this issue.

Serum adiponectin levels in patients with pollen-induced allergic rhinitis.

BACKGROUND: Several studies have outlined a possible relationship between an increased body mass index and respiratory allergic diseases, such as asthma and rhinitis. OBJECTIVE: The aim of the study was to evaluate the serum adiponectin levels in a cohort of patients with pollen-induced allergic rhinitis, enrolled outside the pollen season, and in a group of healthy controls. METHODS: The study included 41 patients with moderate-severe persistent allergic rhinitis due to a pollen allergy and 34 normal subjects. All subjects were prospectively and consecutively evaluated. A skin prick test and blood sampling for assessing serum adiponectin levels were performed in all subjects. RESULTS: The comparison between allergic patients and normal subjects, globally considered without gender distinction, showed slightly higher values in the allergic population. After analysing genders separately, allergic patients show significantly higher levels than normal males (p = 0.0134), whereas the comparison between allergic and normal females was not significant (p = 0.1419). In addition, in normal males adiponectin serum levels are significantly related with age (p = 0.0123). CONCLUSION: This preliminary study provides the first evidence of significantly higher adiponectin serum levels in male patients with pollen-induced allergic rhinitis as compared to normal male subjects.