Serum-induced basophil CD63 expression by means of a tricolour flow cytometric method for the in vitro diagnosis of chronic urticaria

BACKGROUND: Functional autoantibodies against the alpha-chain of the high-affinity IgE receptor (FcepsilonRIalpha) identify a subset of patients with chronic urticaria (CU) due to autoreactivity, as assessed by an in vivo positive response to autologous serum skin test (ASST). We performed a study to standardize the serum-induced basophil activation assay by flow cytometry (FCM) using a new tricolour method, assessing the diagnostic performance of this test in discriminating between ASST+ and ASST- CU patients. METHODS: Sera of 64 CU patients (22 ASST+ CU and 42 ASST- CU) and 10 healthy subjects were tested for their ability to induce basophil CD63 expression when incubated with whole blood of both atopic (DA) and non-atopic donors (DNA). Using a triple-labelled strategy with anti-CD123, anti-HLA-DR and anti-CD63 antibodies, CD63+ basophils were identified on a selected population of CD123+ HLA-DR- cells. In 3 ASST+ CU patients who underwent cyclosporine therapy, the assay was performed before and after treatment. RESULTS: The ASST+ CU sera resulted in a significant higher induction of basophil CD63 expression compared with ASST- CU and healthy donors sera; when whole blood from DA was used, sensitivity and specificity of the assay were 95.5% and 90.5% respectively. ASST+ CU serum activity was significantly decreased during cyclosporine A treatment, in parallel with clinical remission. CONCLUSIONS: Chronic urticaria serum-induced CD63 expression assay performed on DA whole blood by means of our tricolour FCM method could be the most useful tool for identification of a subset of patients with autoimmune CU and may become a promising tool also for monitoring treatment efficacy.     

Validation of basophil histamine release against the autologous serum skin test and outcome of serum-induced basophil histamine release studies in a large population of chronic urticaria patients

BACKGROUND: Endogenous histamine-releasing factors (HRFs) are involved in 30-60% of patients with chronic urticaria (CU). Evidence for their existence comes from in vivo studies of autoreactivity with the autologous serum skin test (ASST), in vitro immunoassays demonstrating autoantibodies against the immunoglobulin E (IgE) or the high affinity IgE receptor (FcepsilonRI) and serum-induced histamine release (HR) from basophils and mast cells. We have examined the correlation between the ASST and a new basophil histamine-releasing assay (the HR-Urtikaria test) in a group of well-characterized CU patients and subsequently determined the frequency of HR-Urticaria-positive sera from a larger population of CU patients. SUBJECTS: Group 1 consisted of 28 patients with CU (16 were ASST-positive) 20 patients with atopic dermatitis, 24 patients with allergy to birch and nine healthy controls. Group 2 consisted of 873 unselected CU patients. METHODS: White blood cells containing 1-2% basophils from a healthy nonatopic donor were incubated with patients sera in the presence of interleukin (IL)-3. Histamine was measured by the glass fibre method. RESULTS: Using the ASST as the true outcome, the HR-Urticaria test showed a sensitivity and specificity of 75% in group 1 using a cut-off value for HR of >16.5%. None of the controls was positive in the HR-Urticaria test. In group 2, we found no difference in the frequency of positives between male (34.6%, n = 254) and female adults (35.1%, n = 576) but twice as many females as males were tested. CONCLUSIONS: Our studies have shown that the HR-Urticaria test has a good sensitivity and specificity for endogenous HRFs demonstrated by the ASST in patients with CU and that about one-third of unselected patients with CU have a positive result.     

EAACI/GA2LEN task force consensus report: the autologous serum skin test in urticaria

Injection of autologous serum collected during disease activity from some patients with chronic spontaneous urticaria (CU) into clinically normal skin elicits an immediate weal and flare response. This observation provides a convincing demonstration of a circulating factor or factors that may be relevant to the understanding of the pathogenesis and management of the disease. This test has become known as the autologous serum skin test (ASST) and is now widely practised despite incomplete agreement about its value and meaning, the methodology and the definition of a positive response. It should be regarded as a test for autoreactivity rather than a specific test for autoimmune urticaria. It has only moderate specificity as a marker for functional autoantibodies against IgE or the high affinity IgE receptor (FcεRI), detected by the basophil histamine release assay, but high negative predictive value for CU patients without them. It is usually negative in other patterns of CU, including those that are physically induced. Positive ASSTs have been reported in some subjects without CU, including those with multiple drug intolerance, patients with respiratory allergy and healthy controls, although the clinical implications of this are uncertain. It is essential that failsafe precautions are taken to ensure that the patient's own serum is used for skin testing and aseptic procedures are followed for sample preparation and handling. CU patients with a positive ASST (ASST⁺) are more likely to be associated with HLADR4, to have autoimmune thyroid disease, a more prolonged disease course and may be less responsive to H1-antihistamine treatment than those with a negative ASST (ASST⁻) although more evidence is needed to confirm these observations conclusively.     

Plasma of patients with chronic urticaria shows signs of thrombin generation, and its intradermal injection causes wheal-and-flare reactions much more frequently than autologous serum

BACKGROUND: Several aspects of the pathogenesis of chronic urticaria (CU) remain contradictory. Autologous serum skin tests (ASSTs) and in vitro histamine release assays seem to look into distinct aspects of the disease, and the specificity of ASST has been questioned. OBJECTIVE: We compared the autologous plasma skin test (APST) with ASST to detect autoreactivity in patients with CU. The clotting process was investigated as well by measuring in vivo thrombin generation. METHODS: A total of 96 adults with CU underwent ASST; 71 of them underwent APST with Na citrate-anticoagulated plasma. Prothrombin fragment 1+2 plasma levels were measured by a sandwich ELISA in Na citrate-anticoagulated plasmas from 28 patients and 27 controls. RESULTS: Fifty-one of 96 (53%) patients scored positive on ASST, whereas 61 of 71 (86%) patients scored positive on APST (21/30 [70%] ASST-negative and 40/41 [98%] ASST-positive). Plasma prothrombin fragment 1+2 was higher in patients than controls (3.06 [SD 3.36] vs 0.80 [0.34]; P < .001) and in ASST-positive/APST-positive than in ASST-negative/APST-positive patients (3.89 [SD 3.68] vs 1.33 [1.64]; P = 0.058) and was directly related to urticaria severity (r = 0.37; P < .05). CONCLUSION: Most patients with CU are positive on APST-Na citrate. CU is associated with the generation of thrombin, a serine protease able to activate mast cells and to cause relevant increase in permeability of endothelium. APST and ASST only partially depend on the presence of circulating antibodies to FcepsilonRI or to IgE. CLINICAL IMPLICATIONS: These findings provide new insights into the pathogenesis of CU and suggest new therapeutic opportunities for treating this disease.     

Autoantibodies to the high-affinity IgE receptor in children with chronic urticaria.

BACKGROUND: Chronic urticaria (CU) in childhood remains a challenge for investigation, and its etiology is largely unknown. Autoantibodies to the high-affinity IgE receptor (FcepsilonRI) are believed to play a role in the pathogenesis of this disease in adults. OBJECTIVE: To determine the prevalence of autoantibodies to FcepsilonRIalpha on basophils in children with CU vs atopic eczema dermatitis syndrome (AEDS). METHODS: Eighty children with CU were compared with 38 children with AEDS. In addition to complete blood cell counts and total IgE measurements, CAP-RASTs to egg, codfish, soy, milk, and peanut were performed. Stool samples were examined for parasites, and autologous serum skin testing and a functional anti-FcepsilonRIalpha assay were conducted to detect autoantibodies. RESULTS: No significant differences were observed between children with CU and controls in mean basophil or eosinophil counts. Twenty (26%) of 77 children with CU and 31 (82%) of 38 with AEDS had positive CAP-RAST results (P < .001). Only 2.5% of the children with CU and 0% with AEDS had stool samples positive for parasites (P = .005). Anti-FcepsilonRIalpha autoantibodies were positive in 37 (47%) of 78 children with CU and in none of 33 with AEDS. Non-IgG histamine-releasing factors were found in 10 (13%) of 78 children with CU. CONCLUSIONS: Children have a similar prevalence of autoantibodies to the FcepsilonRIalpha as has been previously published for adults. Few have type I allergies, and parasite infestation is also uncommon. Further studies are required to investigate the predictive value of the autoantibodies in these children with respect to clinical profile, requirements for medications other than antihistamines, and remission rates.     

Helicobacter pylori infection: prevalence in chronic urticaria patients and incidence of autoimmune urticaria (study in Dr. Cipto Mangunkusumo Hospital, Jakarta)

AIM: To determine the prevalence of Hp infection in patients with chronic urticaria (CU) and to evaluate the result of autologous serum skin test (ASST) in CU patients with Hp infections. METHODS: In this cross-sectional study, 16 patients with chronic urticaria and 16 non-urticaria volunteers were investigated (matched for age and sex). All subjects were examined for Hp infection with the 13C-urea breath test. Autologous serum skin test was performed in patients with proven Hp infection. RESULTS: Helicobacter pylori was detected in 12.5% of patients and 0% of the control group. There was no significant difference between the two groups (p = 0.484 using Fisher exact test). Autologous serum skin test was positive in 1 of 2 CU patients with Hp infection. CONCLUSION: In this study, there was no significant difference in the seroprevalence of Hp infection between CU patients and controls. Autologous serum skin test was positive in 1 of 2 CU patients with Hp infection.     

Autologous serum skin test in chronic idiopathic urticaria: prevalence, correlation and clinical implications

Some cases of chronic idiopathic urticaria (CIU) have histamine-releasing IgG autoantibodies in their blood. This disease subgroup is called "autoimmune urticaria". To date, the autologous serum skin test (ASST) is the best in vivo clinical test for the detection of basophil histamine-releasing activity in vitro. This study aimed to find the prevalence of ASST positive cases in Thai patients with CIU, to identify factors related to the positivity of ASST and to find the clinical implications of ASST in CIU. A retrospective study was performed among 85 CIU patients who attended the Urticaria Clinic at the Department of Dermatology, Siriraj Hospital and were willing to perform ASST, from January 2002 to December 2003. Twenty-one (24.7%) patients had a positive ASST. There was no significant difference between patients with positive ASST and negative ASST as to the severity of the disease (wheal numbers, wheal size, itching scores and the extent of body involvement) as well as the duration of the disease.     

The autologous serum skin test in the follow-up of patients with chronic urticaria

BACKGROUND: The presence of anti-FcepsilonRI and anti-IgE autoantibodies in a subset of patients with chronic urticaria suggests their aetiopathogenetic role. In clinical practice, the presence of these antibodies is usually considered when the autologous serum skin test (ASST) is positive. AIMS: To evaluate if the positive ASST follows up the activity of chronic urticaria. METHODS: Autologous serum skin test and thyroid autoantibody detection were performed in 82 patients with chronic urticaria and repeated 1 year later, when the vast majority of patients were symptom-free. Twenty patients with Hashimoto thyroiditis (HT), who had never suffered from urticaria, represented the control group. RESULTS: At the start of the study, the prevalence of positive ASST was 46.6%. The association of HT-urticaria was 29.3%. ASST was positive in 62 and 39% of patients with and without HT, respectively (P > 0.05 ns). One year later, 28 of 34 patients with a positive ASST were symptom-free, but 50% of them were positive for ASST. The ASST was positive in 86.7 and 8% of patients with and without HT, respectively (P < 0.001). In the control group, ASST was always negative. CONCLUSIONS: The co-existence of autoimmune thyroiditis with chronic urticaria seems to induce a significant difference in the persistence of a positive ASST. Consistent with previous reports, a positive ASST correlates with disease exacerbation in chronic urticaria patients without thyroiditis. In patients with thyroiditis and urticaria, positive ASST persists even after the urticaria has disappeared, thus questioning whether a positive ASST to be a surrogate marker of the functional role of anti-FcepsilonRI and anti-IgE autoantibodies.     

Allergy-like asthma and rhinitis. A cross-sectional survey of a respiratory cohort and a diagnostic approach using the autologous serum skin test

BACKGROUND: Chronic idiopathic urticaria is considered an allergy-like skin disorder, and in some cases an auto-reactivity caused by mast cell degranulating factors has been demonstrated. A positive reaction to the autologous serum skin test (ASST), reflecting the presence of factors capable to degranulate the mast cells, is regarded as a reliable in vivo diagnostic test in chronic urticaria patients. About one out of three patients complaining for rhinitis or asthma does not show sensitization to any allergenic source. No data are available on the application of ASST to respiratory patients. METHODS: A cohort of respiratory patients, aged 1 to 80 years, complaining about suspected respiratory symptoms was screened using a panel of inhalant allergens by means of SPT and IgE. Current and past information on skin and respiratory symptoms were recorded for each patient. Patients were divided in 'allergy' and 'allergy-like' whether or not they react to at least one allergenic source. Age and gender distribution were analyzed. A control group fulfilling criteria for chronic idiopathic urticaria (CIU) was selected as well. The ASST was applied to the control CIU group, to the allergy-like and allergy subsets, and to a group of 58 healthy adult subjects. RESULTS: Allergy and allergy-like patients were differently distributed in relation to age and gender. Allergy-like children were prevalent before age six, whereas the prevalence of allergics steadily increased with age representing the large majority of patients in late childhood. The ratio of allergy/allergy-like subjects continues to increase in adult males, whereas adult females represent the large majority of the adult patients mainly within the allergy-like subset. Fifty-eight percent of CIU control patients reacted to the ASST. Among allergy-like patients ASST was positive in 47% of the adults (male 26%, female 54%), and in 84% of the children (no gender differences). The percentage of reactive subjects increased in the adult allergy-like subset if a CIU was associated (65%). Eighty-six percent of the pediatric patients and 61% of the adults having an allergy respiratory disease associated with an allergy-like condition had a positive ASST reactivity. Pure allergy patients reacted in 73% and 40% of the cases in the children and adults subgroups, respectively. Forty-five percent of healthy controls reacted to the ASST as well, and statistically significant gender differences were still recorded. CONCLUSIONS: An ASST reactivity is reported for the first time in allergy-like respiratory patients. A higher prevalence of reactive subjects has been recorded in all the pediatric subsets without gender differences, whereas female reactivity is prevalent among adults. The ASST reactivity seems to parallel the patient distribution within the entire respiratory cohort. Further studies are needed to demonstrate that the serum factors causing the ASST reactivity in respiratory patients are the same as for CIU affected subjects. In the light of recent in vitro findings, the ASST reactivity of healthy subjects could lead to a new interpretation of the autologous serum reactivity.     

Autoantibodies in chronic idiopathic urticaria and nonurticarial systemic autoimmune disorders

BackgroundChronic idiopathic urticaria (CU) has been associated with other autoimmune diseases and basophil-activating autoantibodies to FcεRI or IgE. It is unknown whether patients with systemicautoimmune diseases have a similar prevalence of these autoantibodies.ObjectiveTo compare the prevalences of basophil-activating autoantibodies (elevated CU Index) in patients with CU, rheumatoid arthritis (RA), and systemic lupus erythematosus (SLE). Clinical characteristics and laboratory studies were examined for an association with the CU Index.MethodsAdult patients, 27 with CU, 27 with RA, and 26 with SLE, and 20 healthy controls were compared on the basis of the CU Index panel, anti-IgE, and antithyroid antibodies.ResultsThe CU Index values were significantly higher in the CU group when compared with the RA group but not when compared with the SLE group. 33% of CU, 23% of SLE, 3.7% of RA, and 15% of controls had apositive CU Index. Elevated antithyroid antibody levels did not correlate with a positive CU Index in any of the groups. An elevated CU Index in the SLE group was not associated with age, sex, ethnicity, disease severity, or history of atopy.ConclusionThe CU Index values were elevated in patients with CU and SLE. The presence of these autoantibodies did not correlate with disease activity or presence of thyroid antibodies. Functional autoantibodies may not be specific for chronic idiopathic urticaria, and their role in nonurticarial systemic autoimmune diseases requires further investigation.     

Assessment of histamine-releasing activity of sera from patients with chronic urticaria showing positive autologous skin test on human basophils and mast cells

BACKGROUND: All previous studies agree that only a proportion of sera from patients with chronic urticaria (CU) positive on the autologous serum skin test (ASST) are able to induce histamine release in vitro. A non-specific release of bradykinins during clotting of blood samples has been suggested; however, ASST seems rather specific and some data point to the existence of a mast cell-specific histamine-releasing factor. OBJECTIVE: To assess whether, and to what extent, the use of both human basophils and mast cells increases the sensitivity of in vitro histamine release assays (HRAs) in ASST-positive patients with CU. METHODS: The histamine-releasing activity of sera from 93 patients with CU selected on the basis of strong skin reactivity on ASST was assessed in vitro on basophils from 1 (n=86), 2 (n=31), or 3 (n=20) normal donors, and on mast cells from 1 (n=3), 2 (n=3), or 3 (n=87) normal donors. RESULTS: Sera from 88/93 (95%) patients induced significant histamine release from mast cells or basophils on at least one HRA. 76/93 (82%), 45/90 (50%), 22/80 (28%), and 6/12 (50%) sera were able to induce significant histamine release from cells of 2/5, 3/5, 4/5 and 5/5 donors, respectively. CONCLUSION: Sera from nearly all ASST-positive patients with CU are able to induce histamine release in vitro. However, the serum from each single patient seems to show its maximal activity on autologous mast cells in vivo, and functional in vitro tests show much variability and seem less sensitive than ASST in the detection of patients with histamine-releasing factors in their blood.     

Chronic urticaria and Helicobacter pylori

Background: Helicobacter pylori (HP) have recently emerged as a novel eliciting factor for chronic urticaria (CU). The possible association between HP and CU has enormous potential, as eradicating HP could cure CU. Aims and Objectives: We conducted a study to assess the prevalence of HP infection and effect of bacterium eradication on skin lesions in patients of chronic idiopathic urticaria (CIU). Settings and Design: Four hundred sixty patients of CU attending the allergy clinic, SMS hospital, Jaipur during the period February 6, 2004, to February 6, 2006, were screened for possible eliciting factors. Patients with CIU were enrolled and others were excluded. Materials and Methods: Sixty-eight patients of CIU and similar number of age and sex matched controls, attending the allergy clinic, SMS Hospital, Jaipur were enrolled in the study. All patients underwent endoscopy with antral biopsy for urease and histopathology to identify HP-associated gastritis. Infected patients were given HP eradication therapy. Eradication of bacterium was confirmed by fecal antigen assay. Subjective response to treatment was judged using chronic urticaria quality-of-life questionnaire (CU-Q 2 oL) while objective response to treatment was judged by need for 'rescue medication' (antihistaminics). Statistical Analysis: Data were analyzed using Chi square and paired't' test for their level of significance. Results: HP associated gastritis was present in 48 (70.58%) patients, out of which 39 (81.25%) patients responded to eradication therapy. Ten (50.00%) patients without HP associated gastritis showed response to symptomatic therapy. Overall 49 (72.05%) patients responded and 19 (27.94%) showed no response. The value of chi2 was 28.571 (P = 0.003), which showed significant association between presence of HP and response to eradication regimen. Conclusion: The response of HP eradication therapy in infected patients of CIU is significant. HP should be included in diagnostic workup of patients with CIU.     

Circulating level of the platelet-derived CXC chemokine platelet factor 4 in chronic urticaria patients with or without coexistent euthyroid Hashimoto's thyroiditis

The concept of autoimmune aetiology of some cases of chronic urticaria (CU) has been supported by several observation including wheal-and-flare reaction induced by intradermal injection of autologous serum as well as association with other autoimmune diseases, in particular Hashimoto's thyroiditis (HT). It is known that activated platelets may actively participate in immune-inflammatory processes. Therefore, we assessed whether autoimmune phenomenon associated with CU influence the systemic platelet activity measured by circulating level of platelet factor 4 (PF-4). Plasma level of PF-4 was analysed using enzyme-linked immunosorbent assay in twelve women with strong positive response to autologous serum skin test (ASST) suffering from CU, twelve female patients with strong positive ASST suffering from both CU and untreated, HT as well as sixteen healthy women. All the subjects were clinically and biochemically euthyroid. There were no statistically significant differences between the CU patients with or without euthyroid HT and plasma PF-4 level in healthy controls. In patients with both CU and thyroiditis, plasma level of PF-4 did not correlate significantly with the level of antibodies against thyroperoxidase. It seems that circulating level of the platelet-derived chemokine is not increased in CU patients with positive response to ASST, regardless the occurrence of euthyroid HT.     

Chronic urticaria and Helicobacter pylori.

BACKGROUND: Although the clinical manifestations of chronic urticaria (CU) are similar in most patients, a variety of factors should be taken into consideration. In general, the cause of CU cannot be determined in most patients, and it is considered idiopathic. In the past several years, relationships between some patients with CU and hepatitis C or autoimmune thyroid diseases have been established. Similarly, other factors may also be considered as possible causes to explain certain patients with CU. Previously, some patients with CU have had their disease attributed to Helicobacter pylori (HP), but the relationship was only clinical. OBJECTIVE: None of the patients previously described included an immunological study. Thus, we studied a patient with CU, who showed marked clinical improvement after eradication of HP, to demonstrate an IgE relationship with this skin disease. METHODS: First, blood analytical parameters, roentgenograms, fecal examination for parasites, and skin tests were performed to try to establish an etiology. In addition, endoscopy with gastric biopsy confirmed HP colonization, and eradication treatment was prescribed. To investigate an immunological relationship, other tests performed included the following: HP-specific IgG, histamine release induced by HP, HP-specific IgE, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis with immunoblotting. RESULTS: The blood analytical parameters, roentgenograms, fecal examination for parasites, and skin tests were all negative. In contrast, the tests for HP-specific IgG, histamine release induced by HP, and HP-specific IgE were all positive. In addition, the sulfate-polyacrylamide gel electrophoresis with immunoblotting showed specific IgE binding to an extract of HP. CONCLUSIONS: Our results may indicate an immunological IgE relationship between HP colonization and CU in this particular patient.     

Immune profiles of patients with chronic idiopathic urticaria

Background: The immunologic characterization of chronic idiopathic urticaria (CIU) is still incomplete. In particular, it is not known if positivity to the intradermal autologous serum skin test (ASST) identifies an immunologic subset of CIU patients. Methods: Nineteen CIU patients and 15 healthy controls were enrolled in the study. A diagnostic flowchart was designed to select CIU patients, who were then analyzed by ASST. Cytokine and chemokine production and the expression of adhesion molecules was measured in patients and controls. Results: In CIU patients compared to controls, it was found that (1) TNF-alpha, IL-10, MIP-1alpha and RANTES production was augmented and IL-2 and INF-gamma reduced, and (2) CD44, CD11a and CD62L expression on CD4 and CD8 cells was augmented. Additionally, TNF-alpha and chemokine production was significantly increased in CIU patients with a negative ASST (p-; n = 10) compared to patients with a positive response to the test. Conclusions: The presence of an inflammatory process in CIU patients is suggested by the findings that the production of both TNF-alpha and chemokines as well as the expression of adhesion molecules is increased in these patients. Similarly to what is seen in rheumatoid arthritis, augmented IL-10 production might be secondary to the attempt to hamper the inflammatory milieu. Immune profiles are particularly altered in CIU p- patients, in whom a more aggressive therapeutic strategy might be considered.     

Association of specific IgE to staphylococcal superantigens with the phenotype of chronic urticaria

It has been well established that bacterial superantigens lead to the induction and aggravation of chronic inflammatory skin diseases. We investigated the clinical significance of serum specific immunoglobulin E (lgE) to the staphylococcal superantigens staphylococcal enterotoxin A (SEA), staphylococcal enterotoxin B (SEB), and toxic shock syndrome toxin (TSST)-1 in patients with chronic urticaria (CU), focusing on the differences in these prevalences between aspirin-intolerant CU (AICU) and aspirin-tolerant CU (ATCU) patients. Aspirin sensitivity was confirmed by oral aspirin provocation test. There were 66 patients AICU and 117 patients ATCU in the study. Serum IgE antibodies specific for SEA, SEB, and TSST-1 were measured by the ImmunoCAP test and the patients were compared with 93 normal controls (NC). The prevalences of serum specific IgE to staphylococcal superantigens were significantly higher in CU than in NC patients (IgE to SEA, 13.7% vs. 5.4%; IgE to SEB, 12.0% vs. 4.3%; IgE to TSST-1, 18.0% vs. 6.5%; p<0.05, respectively). The patients with specific IgE to SEA, SEB, and TSST-1 had higher serum total IgE levels and higher rates of atopy. Significant associations were noted between the prevalence of specific IgE to SEA and SEB and the HLA DQB1*0609 and DRB1*1302 alleles in the AICU group. We confirmed that a sub-population of patients with CU possesses serum IgE antibodies to SEA, SEB, and TSST- 1. Particularly, the IgE immune response to TSST-1 is associated with aspirin sensitivity in CU patients.     

Chronic urticaria sera increase basophil CD203c expression

BACKGROUND: Approximately 40% of patients with chronic idiopathic urticaria have antibodies to the alpha subunit of the high-affinity IgE receptor. CD203c is a basophil activation marker known to be upregulated by cross-linking of the FcepsilonRIalpha receptor and may serve as a useful marker to identify these patients. OBJECTIVE: The primary objective was to assess the affect of sera from patients with chronic idiopathic urticaria on basophil CD203c expression. Secondary objectives were to correlate CD203c expression with basophil histamine release and size of the autologous serum skin test and to determine whether the mechanism is mediated by an IgG antibody. METHODS: Sera were obtained from patients with chronic idiopathic urticaria and positive autologous serum skin test or negative autologous serum skin test and normal controls. Sera were incubated with donor whole blood. Activated basophils from whole blood were identified by flow cytometry on the basis of the presence of CD203c on high-expressing IgE positive cells. RESULTS: Incubation of donor basophils with sera from patients with chronic idiopathic urticaria and positive autologous serum skin test demonstrated significant upregulation of CD203c. IgG depletion of representative sera from patients with chronic idiopathic urticaria resulted in significant decrease in CD203c expression on donor basophils. CD203c expression correlated with basophil histamine release and the size of the autologous serum skin test. CONCLUSION: Sera from patients with chronic idiopathic urticaria and positive autologous serum skin test significantly upregulate basophil CD203c and correlate with basophil histamine release. CLINICAL IMPLICATIONS: This article describes an activation marker on basophils whose expression is increased by sera from patients with chronic idiopathic urticaria.     

Increased responsiveness of basophils of patients with chronic urticaria to sera but hypo-responsiveness to other stimuli

BACKGROUND: Although it has been shown that basophils from patients with chronic ordinary urticaria (CU) are less responsive than normal basophils when stimulated with anti-IgE, very few studies have examined the response of those cells to alternative stimuli. OBJECTIVE: To compare releasability between basophils from healthy donors and patients with CU. METHODS: We examined the response of IL-3-treated basophils from healthy donors, atopic controls and CU patients to anti-IgE, monocyte chemoattractant protein-1 (MCP-1), bradykinin, C5a and to sera obtained from other urticaria patients and normal controls. We also compared the response of basophils from CU patients whose sera activate normal basophils (autoimmune CU) from those who do not (idiopathic CU). RESULTS: Basophils of CU patients release significantly less histamine than basophils of normal controls when stimulated with anti-IgE, and to a lesser degree with C5a. No differences were observed when basophils from patients were incubated with Bradykinin or MCP-1. However, when basophils of CU patients were incubated with sera from other CU patients or even normal sera, we found significantly higher histamine release compared with the response of basophils from normal donors. We could not distinguish responsiveness of basophils of patients with chronic autoimmune urticaria from patients with chronic idiopathic urticaria. CONCLUSION: Basophils of patients with chronic idiopathic urticaria and chronic autoimmune urticaria are hypo-responsive to anti-IgE and C5a, normally responsive to MCP-1 or bradykinin, and hyper-responsive to serum. The serum factor to which a response has not yet been identified; however, basophils of patients with chronic urticaria, in general, appear to have abnormal regulation of signaling pathways.     

Effect of omalizumab on patients with chronic urticaria.

BACKGROUND: Chronic urticaria (CU) is often difficult to treat. Approximately 40% to 50% of patients with no apparent cause are believed to have an associated autoimmune profile that may play a pathogenetic role. OBJECTIVES: To describe 3 patients with CU refractory to conventional treatment who responded to omalizumab therapy. METHODS: Treatment was maximized with antihistamines, antileukotrienes, and histamine2 blockers with no improvement. Systemic steroids provided only temporary relief. Laboratory workup revealed 1 patient with a low IgE level and elevated anti-IgE receptor antibody level, 1 patient with an elevated IgE level but a normal anti-IgE receptor antibody level, and 1 patient with a very elevated IgE level and an elevated anti-IgE receptor antibody level. All 3 patients were prescribed omalizumab therapy every 2 weeks. RESULTS: Two patients had total clearing of urticaria within 1 week and 1 patient within 6 weeks of starting omalizumab therapy. The patient with the elevated anti-IgE receptor antibody level had normalization of the level after starting treatment. CONCLUSIONS: Omalizumab may have a beneficial effect in the treatment of CU. Further studies are needed to confirm this effect and better elucidate the mechanism for the observed improvement.     

Clinical and laboratory parameters in predicting chronic urticaria duration: a prospective study of 139 patients

BACKGROUND: Despite the disabling nature of chronic urticaria (CU), little is known about the disease's duration or the efficacy of adopting aggressive therapeutic regimens such as cyclosporine A. OBJECTIVES: The aim of this study was to evaluate whether parameters such as angioedema, autologous serum test, anti-thyroid antibodies, and total IgE could predict both CU duration and severity. PATIENTS AND METHODS: One hundred and thirty-nine patients suffering from CU were prospectively followed over a 5-year period for disease duration, severity and the presence of angioedema. Also investigated was the association between these clinical parameters and the subsequent detection of autologous serum test, anti-thyroid antibodies, and total IgE. RESULTS: CU lasted over 1 year in more than 70% of cases and in 14% it still existed after 5 years. Angioedema co-existed or appeared during the course of CU in 40% of patients and was associated with disease duration. Autologous serum test and anti-thyroid antibodies were found positive in 28 and 12% of patients, respectively, compared to none of normal individuals, P = 0.001. CU duration was associated with the presence of both autologous serum test and anti-thyroid antibodies; however, autologous serum test and not anti-thyroid antibodies was found in association with CU severity. CONCLUSION: We demonstrate for the first time that CU duration is associated with clinical parameters such as severity and angioedema, and with laboratory parameters such as autologous serum test and anti-thyroid antibodies. The ability to predict CU duration may facilitate decisions regarding the possible early initiation of cyclosporine A as a means by which to reduce disease severity and duration.