Chronic Idiopathic Urticaria Subjects Research Articles

Expression Of TSLP and TSLP-R In Chronic Idiopathic Urticaria

In mice, TSLP elicits a distinct subset of basophils with increased cytokine expression and decreased degranulation responses relative to IL-3 elicited basophils. In humans, TSLP expression is noted in skin lesions of atopic dermatitis subjects and thought to promote Th2 responses. Since human basophils show suppressed IgE receptor degranulation responses in chronic idiopathic urticaria (CIU), we explored TSLP expression in skin and TSLP-R expression on basophils of CIU subjects.

Cultured peripheral blood mast cells from chronic idiopathic urticaria patients spontaneously degranulate upon IgE sensitization: Relationship to expression of Syk and SHIP-2

Recently, signaling changes in the FcvarepsilonRI pathway involving inositol lipid phosphatases have been identified in the basophils of chronic idiopathic urticaria (CIU) subjects. Based on the profile of basophil FcvarepsilonRI-mediated histamine degranulation, we have segregated CIU subjects into two groups, CIU Responder (CIU R) or CIU Nonresponder (CIU NR). In the present study, we compared expression of SHIP-1, SHIP-2, and Syk protein to histamine release (HR) from mast cells (MC) cultured from the peripheral blood of CIU R, CIU NR, and normal subjects. The MC of CIU R donors contained significantly increased Syk and decreased SHIP-2 as compared to CIU NR (Syk: p=0.038, SHIP-2: p=0.038) and normals (Syk: p=0.042, SHIP-2: p=0.027). Spontaneous HR from CIU donors was increased two-fold compared to normals (p=0.04). In summary, our results suggest a possible predilection for urticarial MC to spontaneously degranulate upon IgE sensitization contributing to the increased pruritus associated with CIU.

Gene Expression Profiling of Nonlesional Skin from Chronic Idiopathic Urticaria Subjects is Distinct from Normal Nonatopic Skin

Gene Expression Profiling of Nonlesional Skin from Chronic Idiopathic Urticaria Subjects is Distinct from Normal Nonatopic Skin

Basophil Phenotypes in Chronic Idiopathic Urticaria in Relation to Disease Activity and Autoantibodies

Potentially pathogenic IgG autoantibodies to IgE or its receptor, Fc epsilonRIalpha, have been detected in approximately 40% of chronic idiopathic urticaria (CIU) patients. CIU patients' basophils display distinct altered Fc epsilonRIalpha-mediated degranulation. CIU patients with basophil histamine release in response to polyclonal goat anti-human IgE > or = 10% are classified as CIU responders (CIU-R) and < 10% are CIU non-responders (CIU-NR). We compared the presence of autoantibodies to basophil degranulation phenotypes and to disease status (active or inactive). Sera were collected from non-CIU subjects and CIU subjects who participated in a longitudinal study of disease severity and had defined basophil degranulation phenotypes. Immunoenzymetric assays (IEMA) quantified IgG anti-Fc epsilonRIalpha and anti-IgE. IgG anti-Fc epsilonRIalpha antibody was detected in 57% of CIU-R (n=35), 55% of CIU-NR (n=29), and 57% of non-CIU subjects (n=23), whereas IgG anti-IgE was present in 43% of CIU-R, 45% of CIU-NR, and 30% of non-CIU subjects. Both the autoantibody levels and the functional basophil phenotype remained stable in subjects with active disease (n=16), whereas there was an enhancement in basophil function as subjects evolved into a state of remission (n=6), which appears independent of the presence of autoantibody. IEMAs detected a similar frequency of autoantibodies in CIU-R, CIU-NR, and non-CIU subjects. Basophil function may be independent of IEMA-detected autoantibodies.

Longitudinal Examination of Basophil Functional Phenotypes and Disease Activity in Chronic Idiopathic Urticaria (CIU)

RATIONALE: Previously, we demonstrated that 50% of CIU patients' basophils have a “nonresponder” (CIU-NR) functional phenotype, defined as <10% histamine release (HR), with optimal anti-IgE stimulation. CIU-NR basophils also require a ten-fold higher anti-IgE concentration to reach maximal HR when compared to CIU “responder” (CIU-R) basophils and those from non-CIU donors. In the present study, we have examined the persistence of the CIU basophil functional phenotype relative to CIU disease activity. METHODS: Since 2002, 66 CIU subjects were recruited from university allergy and dermatology clinics. After informed consent, basophils were isolated by dextran sedimentation and stimulated with polyclonal goat anti-human IgE (0.01-3 μg/mL) and FMLP (10-6 M), and HR was measured by automated fluorimetry. The majority of subjects (55 of 66) also completed a disease severity questionnaire. RESULTS: Of the 66 subjects sampled, 57 were initially classified by basophil functional phenotype (29 CIU-NR and 28 CIU-R), and 9 specimens were indeterminate due to basopenia. Twenty-four of 57 classified subjects had a second sample an average of 17.2 ± 3.8 months from the initial sample (range 0.5-53 months). Basophil functional phenotype remained stable in subjects with persistent CIU disease activity (n = 18). In contrast, subjects with remission of CIU disease were noted to have heightened sensitivity (CIU-R and CIU-NR) and magnitude of HR (CIU-NR) to anti-IgE. CONCLUSIONS: CIU basophil functional phenotypes (CIU-NR and CIU-R) persist with continued CIU disease activity but shift in disease remission. These findings suggest that basophil HR patterns may be useful markers of CIU disease activity.

Basophil FcɛRI histamine release parallels expression of Src-homology 2–containing inositol phosphatases in chronic idiopathic urticaria

Basophils are implicated in the pathogenesis of chronic idiopathic urticaria (CIU). Autoantibodies to the IgE receptor (FcepsilonRI) and serum histamine releasing activity have been detected in some subjects with CIU, although their role in vivo is unclear. Basophils of patients with CIU have altered FcepsilonRI-mediated histamine release (HR); however, the mechanism is unknown. In the basophil FcepsilonRI signaling pathway, protein levels of Src-homology 2-containing-5'-inositol phosphatase (SHIP)-1 are inversely correlated with the release of mediators or releasability. A related phosphatase, SHIP-2, is a negative regulator of monocyte IgG receptor (FcgammaR) signaling . We hypothesized that SHIP levels are altered in CIU basophils. Blood basophils were isolated from cold urticaria, CIU, or normal donors, and FcepsilonRI-dependent and independent HR were quantified. Protein levels of SHIP-1, SHIP-2, spleen tyrosine kinase, and phosphorylated Akt were determined by Western blotting. Subjects' serum was tested for serum histamine releasing activity and anti-FcepsilonRIalpha antibodies. CIU basophils displayed a bimodal response to anti-IgE activation. One half of CIU subjects' basophils had reductions in anti-IgE-induced HR and were designated nonresponders (CIU NR). CIU NR basophil HR remained diminished at 10-fold to 30-fold higher doses of anti-IgE. CIU anti-IgE responder basophils had HR similar to normal subjects. SHIP-1 and SHIP-2 proteins were increased in CIU NR basophils and were linked to reduced phosphoAkt after anti-IgE stimulation. CIU basophil anti-IgE response was not related to the presence of serologic factors. In CIU basophils, the observed changes in FcepsilonRI signaling pathway molecule expression may underlie changes in releasability. Patients with CIU can be segregated on the basis of basophil functional phenotype.

Evidence of in vivo basophil activation in chronic idiopathic urticaria

Approximately 40% of chronic idiopathic urticaria (CIU) subjects have autoantibodies to either FcepsilonRIalpha or IgE. The effect of such autoantibodies on circulating basophil activation status is unknown. The expression of cell surface activation markers on basophils from CIU, non-allergic, and allergic subjects were compared. Further, the relationship between marker expression and serum factors reported in CIU, such as histamine-releasing activity (HRA) and immunoreactivity to FcepsilonRIalpha were examined. Peripheral blood was obtained from CIU, allergic, and non-allergic donors and fractionated by density gradients. Enriched basophils (1-12%) were analysed by flow cytometry for expression of activation markers including CD63, CD69, and CD203c. Dilutions of serum (5-50%) were analysed for HRA on basophils from a normal donor. Serum was tested for immunoreactivity by western blotting to a standard cell lysate prepared from an RBL-SX38 cell line transfected with human FcepsilonRIalpha. CIU subjects (n=9) and allergic subjects (n=8) exhibited enhanced expression of CD63 and CD69, as compared with non-allergic subjects (n=7); however, no difference was seen among groups for CD203c expression. Five CIU and two non-allergic subjects had evidence of significant serum HRA (>20%), whereas two CIU, two allergic, and three non-allergic subjects had evidence of serum immunoreactivity to FcepsilonRIalpha. Serum HRA and serum immunoreactivity to FcepsilonRIalpha were not associated with enhanced surface marker expression. Basophil activation marker expression is increased in CIU subjects and is not associated with serum factors. In addition, serum HRA and FcepsilonRIalpha immunoreactivity are not unique to CIU, or related to enhanced circulating basophil marker expression.

Autoantibodies Against the High Affinity IgE Receptor (FcεR1α) are Equally Prevalent in Patients with Auto-Immune Thyroid Disease, Chronic Idiopathic Urticaria and Controls

RATIONALE: Chronic idiopathic urticaria (CIU) is characterized by hives of uncertain etiology of >6 weeks duration. Investigators have identified auto-antibodies directed against the high affinity IgE receptor alpha chain (FcεR1α) on mast cells in many of these patients. Approximately 30% of patients with CIU also have autoimmune thyroiditis. The aim of this study was to determine the incidence of FcεR1α auto-antibodies in patients with CIU, Hashimoto's thyroiditis, and control groups and to correlate their presence with positive autologous serum skin testing (ASST) and autoimmune thyroiditis.METHODS: Individuals with Hashimoto's thyroiditis (n = 10), CIU (n = 18) and controls (n = 22) were enrolled into the study. All subjects had blood drawn and evaluated for TSH, free T4 (if TSH abnormal) and thyroid auto-antibodies. All patients underwent ASST and had serum screened for the presence of anti-FcεR1α antibodies by ELISA.RESULTS: We developed and validated our ability to reproducibly quantify anti-FcεR1α antibodies. However, no statistically significant differences in the incidence of anti-FcεR1α antibodies were identified between control patients (33%) and patients with CIU (35%), Hashimoto's (30%) or patients with both CIU and Hashimoto's (35%). Anti-thyroid antibodies were present in 18% of controls and 44% of CIU patients. The ASST was positive in 22% of controls and in 60% of CIU patients. The prevalence of anti-thyroid antibodies did not differ between CIU patients with and without ASST.CONCLUSIONS: Anti-FcεR1α antibodies are equally prevalent in control, Hashimoto's and CIU subjects. ASST positivity does not correlate with the presence of anti-thyroid antibodies. RATIONALE: Chronic idiopathic urticaria (CIU) is characterized by hives of uncertain etiology of >6 weeks duration. Investigators have identified auto-antibodies directed against the high affinity IgE receptor alpha chain (FcεR1α) on mast cells in many of these patients. Approximately 30% of patients with CIU also have autoimmune thyroiditis. The aim of this study was to determine the incidence of FcεR1α auto-antibodies in patients with CIU, Hashimoto's thyroiditis, and control groups and to correlate their presence with positive autologous serum skin testing (ASST) and autoimmune thyroiditis. METHODS: Individuals with Hashimoto's thyroiditis (n = 10), CIU (n = 18) and controls (n = 22) were enrolled into the study. All subjects had blood drawn and evaluated for TSH, free T4 (if TSH abnormal) and thyroid auto-antibodies. All patients underwent ASST and had serum screened for the presence of anti-FcεR1α antibodies by ELISA. RESULTS: We developed and validated our ability to reproducibly quantify anti-FcεR1α antibodies. However, no statistically significant differences in the incidence of anti-FcεR1α antibodies were identified between control patients (33%) and patients with CIU (35%), Hashimoto's (30%) or patients with both CIU and Hashimoto's (35%). Anti-thyroid antibodies were present in 18% of controls and 44% of CIU patients. The ASST was positive in 22% of controls and in 60% of CIU patients. The prevalence of anti-thyroid antibodies did not differ between CIU patients with and without ASST. CONCLUSIONS: Anti-FcεR1α antibodies are equally prevalent in control, Hashimoto's and CIU subjects. ASST positivity does not correlate with the presence of anti-thyroid antibodies.

Basophil Histamine Release (HR) Activity and Disease Severity in Chronic Idiopathic Urticaria (CIU)

RATIONALE: To assess CIU disease severity and activity in relation to basophil HR characteristics.METHODS: CIU subjects were recruited from university allergy and dermatology clinics. Subjects were excluded if they had recent use of systemic steroids or immunosuppressants. After being consented, subjects completed a disease severity questionnaire. Blood basophils of subjects were isolated by dextran sedimentation and stimulated for HR with polyclonal goat anti-human IgE. HR was measured by automated fluorimetry. Multivariable linear regression analyses were used to investigate the relationship between histamine release data and disease measures.RESULTS: Thirty-four subjects were enrolled with the following characteristics: mean age, 44 yrs; females, n = 27; Caucasian, n = 24; disease duration >4 years, n = 18; and family history of hives, n = 9. In the past year, 52% of subjects received > 1 steroid taper, 17% visited the ER for CIU and 62% reported > 1 d of work or school absence. The linear regression revealed a significant inverse relationship between current itch severity and blood histamine content (p = . 036), a measure of basophil presence in the circulation, after controlling for potential confounders such as race, gender, disease duration, family history and medications used.CONCLUSIONS: This study suggests CIU subjects have a significant disease burden. The inverse relationship between itch severity and blood histamine content identified supports prior observations that basopenia is linked to disease activity. Further, the reduction of blood basophils may indicate their recruitment to urticarial lesions as recently reported. RATIONALE: To assess CIU disease severity and activity in relation to basophil HR characteristics. METHODS: CIU subjects were recruited from university allergy and dermatology clinics. Subjects were excluded if they had recent use of systemic steroids or immunosuppressants. After being consented, subjects completed a disease severity questionnaire. Blood basophils of subjects were isolated by dextran sedimentation and stimulated for HR with polyclonal goat anti-human IgE. HR was measured by automated fluorimetry. Multivariable linear regression analyses were used to investigate the relationship between histamine release data and disease measures. RESULTS: Thirty-four subjects were enrolled with the following characteristics: mean age, 44 yrs; females, n = 27; Caucasian, n = 24; disease duration >4 years, n = 18; and family history of hives, n = 9. In the past year, 52% of subjects received > 1 steroid taper, 17% visited the ER for CIU and 62% reported > 1 d of work or school absence. The linear regression revealed a significant inverse relationship between current itch severity and blood histamine content (p = . 036), a measure of basophil presence in the circulation, after controlling for potential confounders such as race, gender, disease duration, family history and medications used. CONCLUSIONS: This study suggests CIU subjects have a significant disease burden. The inverse relationship between itch severity and blood histamine content identified supports prior observations that basopenia is linked to disease activity. Further, the reduction of blood basophils may indicate their recruitment to urticarial lesions as recently reported.

Evidence of in vivo basophil activation in chronic idiopathic urticaria

Rationale Approximately 40% of chronic idiopathic urticaria (CIU) subjects have autoantibodies to FceRIa or to IgE. However, the effect of such autoantibodies on circulating basophil activation status is unclear. We compared the basophils from CIU and allergic subjects for expression of cell surface activation markers. We also examined the serum of donors for histamine releasing activity (HRA) and for immunoreactivity to FceRIa protein. Methods Peripheral blood was obtained from CIU and allergic donors and fractionated by density gradient centrifugation. Enriched basophils (1–8%)were analyzed by flow cytometry for expression of activation markers including CD 69, CD 63, and CD203. Dilutions of serum (5, 25, 50%) were analyzed for HRA on basophils from a single donor. Serum was also tested for immunoreactivity by Western blotting to a standard cell lysate prepared from RBL-SX38 transfected with the human FceRIa. Results CIU subjects (n=5) demonstrated enhanced expression of all three surface markers as compared to allergic donors (n=5): CD 63, 220 vs. 13.9; CD69, 108 vs. 4.6 and CD203, 4.17 vs. 1.4 (net mean fluorescence intensity units). Three CIU subjects had evidence of significant serum HRA (>20%) on donor basophils. Two CIU donors had evidence of immunoreactivity for FceRIa as compared to none of the allergic donors. The two CIU subjects with both serum HRA and immunoreactivity also had altered basophil function as measured by anti-IgE mediated stimulation. Conclusions Basophils from CIU subjects express increased levels of activation markers as compared to allergic subjects. Heightened basophil activation in CIU may be due to circulating serum factors.

Autoantibody production in chronic idiopathic urticaria is not associated with Helicobacter pylori infection.

Chronic idiopathic urticaria (CIU) is a dermatological syndrome, characterized by raised erythematous skin lesions, that affects 20% of the general population and has been associated with autoimmunity. However, some reports have also suggested a close relationship between CIU and Helicobacter pylori infection, which is endemic in developing countries and associated with chronic gastritis, peptic ulcer disease, and gastric carcinoma. In the present study, we investigated the occurrence of autoantibodies in sera from 23 CIU subjects infected with H. pylori and from 23 CIU subjects without this infection. The presence of anti-thyroid antibodies was determined by indirect hemagglutination assay and the presence of autoantibodies to IgE and C1INH was determined by ELISA. Antibodies to thyroid antigens were detected at low titers from 100 to 400 in three of 23 (13%) CIU-infected subjects and in four of 23 (17%) CIU-noninfected subjects. The titers of anti-IgE autoantibodies were similar in these CIU groups, presenting absorbances of 1.16 +/- 0.09 and 1.07 +/- 0.16, respectively, while a titer of 1.14 +/- 0.15 was detected in the healthy control group. The concentration of anti-C1INH autoantibodies was the same in the CIU-infected and -noninfected subjects (7.28 +/- 1.31 and 7.91 +/- 2.45 ng/ml, respectively), and was 7.20 +/- 2.25 ng/ml in the healthy control group. However, the serum levels of complexed anti-C1INH antibodies were increased in CIU-infected subjects compared to CIU-noninfected subjects and healthy controls with an absorbance of 1.51 +/- 0.21 vs 1.36 +/- 0.16 and 1.26 +/- 0.23, respectively (P<0.05), indicating an impaired clearance of immune complexes in CIU-infected patients. In conclusion, no correlation was observed between H. pylori infection and autoantibody production in CIU patients consistent with reports of clinical studies.