Different hypersensitivities against homologous proteins of MGL_1304 in patients with atopic dermatitis.

BACKGROUND: Atopic dermatitis (AD) is exacerbated by sweating, and the skin of most patients with AD are resided by Malassezia (M.) fungi. Recently, MGL_1304 produced by Malassezia globosa was identified as the major histamine releasing antigen in human sweat. METHODS: The full length cDNA of the counterpart of MGL_1304 in Malassezia restricta (Mala r 8), was cloned by degenerate PCR and rapid identification of cDNA ends (RACE). Recombinant MGL_1304, and its counterparts, Mala s 8 (produced by Malassezia sympodialis) and Mala r 8 were prepared, and compared in their allergenicities by dot blot analysis and histamine release tests with sera and basophils of patients with AD. RESULTS: The identities between MGL_1304 and Mala s 8, MGL_1304 and Mala r 8, and Mala s 8 and Mala r 8 were 68%, 78%, and 76%, respectively, in protein sequences. Dot blot analysis revealed that the level of IgE binding to Mala s 8 was higher than that of MGL_1304. However, histamine release tests revealed that MGL_1304 and Mala r 8 possessed higher activity than Mala s 8. In addition, the crude lysate of M. globosa showed higher histamine release ability than that of M. sympodialis. CONCLUSIONS: Patients with AD showed hypersensitivities against MGL_1304 and its homologs. However, the allergenicities of the homologs are variable and the histamine release activities may be different from the solid-phase binding activities for IgE. Sweat allergy should be carefully evaluated with biological activities of MGL_1304 and its homologs of other Malassezia fungi residing on the skin.

Analysis of primary treatment and prognosis of spontaneous urticaria.

BACKGROUND: The prognosis of spontaneous urticaria in association with early treatment remains unclear. In this study, we retrospectively studied the prognosis of acute spontaneous urticaria in relation to age and treatments in a local clinic of dermatology. METHODS: Out of 5000 patients who visited an office dermatology clinic, clinical records of patients with spontaneous urticaria were extracted. Their prognosis and the relation to age and treatments were analyzed by the Kaplan-Meier method and generalized Wilcoxon test. RESULTS: Among 386 patients diagnosed with spontaneous urticaria, 284 patients (73.6%) began treatments within a week after the onset. Their non-remission rates after one week, four weeks and one year from the onset were 26.8%, 15.0% and 6.7%, respectively. The non-remission rates of patients who were 20-years-old or younger by one year after the onset of urticaria, were significantly lower than those of patients older than 20-years-old. No apparent relationship between remission rates and sex or the use of steroids was detected. However, the non-remission rates of urticaria treated with a standard dose of antihistamine were lower than that treated with additional medications. CONCLUSIONS: Most patients who began treatments within one week from the onset remitted quickly. However approximately 7% of them continued to suffer from symptoms for more than a year. Such prolongation tended to be seen among patients who required other medications in addition to a standard dose of antihistamine.

A human monoclonal IgE antibody that binds to MGL_1304, a major allergen in human sweat, without activation of mast cells and basophils.

MGL_1304, a major allergen in human sweat for patients with atopic dermatitis and/or cholinergic urticaria, is secreted from Malassezia globosa on human skin. The amounts of MGL_1304 and IgE against MGL_1304 are evaluated by the histamine release test using basophils or mast cells sensitized with serum containing IgE against MGL_1304, and enzyme linked sorbent assay (ELISA) using MGL_1304 and anti-MGL_1304 antibodies. Here, we identified a human monoclonal IgE (ABS-IgE) that binds to the high affinity IgE receptor (FcεRI) and MGL_1304 with high affinity (KD = 1.99 nM) but does not release histamine from basophils and mast cells. An ELISA using ABS-IgE as a standard IgE revealed that the amount of IgE against MGL_1304 (1000 U/ml) in the standard sera of patients with AD, employed in our previous report, is 32 ng/ml. A sandwich ELISA using ABS-IgE as a detection antibody showed approximately 10 times lower detection limit for MGL_1304 than ELISA in which MGL_1304 is directly bound to an ELISA plate. Moreover, ABS-IgE prevented histamine release from mast cells and basophils by neutralizing MGL_1304 not only in a free form in solution, but also on FcεRI expressed on the cell surface without cell activation. ABS-IgE may be used both to quantify the amount of MGL_1304 and anti-MGL_1304 IgE, and possibly for the treatment of diseases caused/aggravated by type I allergy to MGL_1304.

Evaluation of recombinant MGL_1304 produced by Pichia pastoris for clinical application to sweat allergy.

BACKGROUND: We previously identified MGL_1304 secreted by Malassezia globosa as a sweat antigen for patients with atopic dermatitis (AD) and cholinergic urticaria (ChU). However, purifying native MGL_1304 from human sweat or culture supernatant of M. globosa (sup-MGL_1304) is costly and time-consuming. Moreover, recombinant MGL_1304 expressed by using Escherichia coli (TF-rMGL_1304) needs a large chaperon protein and lacks the original glycosylation of yeasts. Thus, we generated a recombinant MGL_1304 by Pichia pastoris (P-rMGL_1304) and investigated its characteristic features. METHODS: Recombinant MGL_1304 proteins expressed by E. coli and P. pastoris were generated. Properties of these recombinants and native antigens were compared by western blot analysis, histamine release tests (HRT) of patients with AD and ChU, and ß-hexosaminidase release tests with RBL-48 cells. P-rMGL_1304-specific IgE in sera of patients with AD were measured by sandwich ELISA. RESULTS: Western blot analysis revealed that IgE of patients with AD bound to all MGL_1304 recombinants and native antigens. The histamine releasing ability of P-rMGL_1304 was 100 times higher than that of TF-rMGL_1304, and was comparable to that of sup-MGL_1304. Degranulation rates of RBL-48 cells, sensitized with sera of patients with AD in response to the stimulation of P-rMGL_1304, were comparable to those of sup-MGL_1304, whereas those of TF-rMGL_1304 were relatively weak. The levels of P-rMGL_1304-specific IgE in sera of patients with AD were correlated with their disease severities. CONCLUSIONS: P-rMGL_1304 has an antigenicity comparable to the native antigen, and is more useful than TF-rMGL_1304, especially in HRT and degranulation assay of RBL-48 cells.

[ANALYSIS OF PRIMARY TREATMENT AND PROGNOSIS OF SPONTANEOUS URTICARIA IN A LOCAL CLINIC OF OFFICE DERMATOLOGY].

BACKGROUND: Prognosis of spontaneous urticaria in association with early treatment remained unclear. In this study, we retrospectively studied the prognosis of acute spontaneous urticaria in relation to age and treatments in a local clinic of dermatology. METHODS: Out of 5000 patients who visited an office dermatology clinic, clinical records of patients with spontaneous urticaria were extracted. Their prognosis and the relation to age and treatments were analyzed by the Kaplan-Meier method and generalized Wilcoxon test. RESULTS: Among 386 patients diagnosed as spontaneous urticaria, 284 patients (73.6%) had begun treatments within a week after the onset. The non-remission rates of them after one week, four week and one year from the onset were 26.8%, 15.0% and 6.7%, respectively. The non-remission rate of patients who were 20-years-old or younger by one year after the onset of urticaria, was significantly lower than that of patients older than 20-years-old. No apparent relations between the remission rate and sex or the use of steroids was detected. However, the non-remission rate of urticaria that was treated with a standard dose of antihistamine was lower than that treated with additional medications. CONCLUSION: Most patients who began treatments within one week from the onset remitted shortly. However approximately 7% of them continued to suffer from symptoms for more than a year. Such prolongation tends to be seen among patients who required other medications in addition to standard dose of antihistamine.

Non-tumor mast cells cultured in vitro on a honeycomb-like structured film proliferate with multinucleated formation.

Mast cells are released from bone marrow into the circulatory system as immature precursors and differentiate upon their arrival at diverse organs and tissues. Because mast cell functions can be altered in these tissues, we propose that mast cells are sensitive to their surrounding microenvironment. To examine the morphological responses of mast cells, we cultured a proliferative mouse non-tumor cell line of mast cells (NCL-2 cells) on a honeycomb-like structured polystyrene film (HCF) representing a microenvironmental scaffold. In this study, the NCL-2 cells cultured on the HCF proliferated without apoptosis. Furthermore, NCL-2 cells cultured on 3- and 5-µm HCFs exhibited multinuclear formation. These observations of different NCL-2 cell morphologies and proliferation rates on HCF scaffolds with different hole sizes suggest that mast cells undertake specific proliferative shapes depending on the surrounding microenviroment. Moreover, HCFs may lead to the regulation of mast cell differentiation. FROM THE CLINICAL EDITOR: This team reports on the development of a honeycomb-like structured film to study mast cell differentiation of non-cancerous origin, demonstrating that different microenvironments provided by different honeycomb hole sizes determine the morphology of the differentiated cells.

Surface plasmon resonance for cell-based clinical diagnosis.

Non-invasive real-time observations and the evaluation of living cell conditions and functions are increasingly demanded in life sciences. Surface plasmon resonance (SPR) sensors detect the refractive index (RI) changes on the surface of sensor chips in label-free and on a real-time basis. Using SPR sensors, we and other groups have developed techniques to evaluate living cells' reactions in response to stimuli without any labeling in a real-time manner. The SPR imaging (SPRI) system for living cells may visualize single cell reactions and has the potential to expand application of SPR cell sensing for clinical diagnosis, such as multi-array cell diagnostic systems and detection of malignant cells among normal cells in combination with rapid cell isolation techniques.

Fungal protein MGL_1304 in sweat is an allergen for atopic dermatitis patients.

BACKGROUND: Sweat is a major aggravating factor of atopic dermatitis (AD) and approximately 80% of patients with AD show type I hypersensitivity against sweat. OBJECTIVE: To identify and characterize an antigen in sweat that induces histamine release from basophils of patients with AD. METHODS: Basophil histamine-releasing activity in sweat was purified by a combination of chromatographies, and proteins were analyzed with mass spectrometry. Recombinant proteins of the sweat antigen were generated, and their biological characteristics were studied by immunoblots, histamine release tests, and neutralization assays. RESULTS: We identified a fungal protein, MGL_1304, derived from Malassezia globosa (M globosa) in the purified sweat antigen. Recombinant MGL_1304 induced histamine release from basophils of most of the patients with AD, in accordance with the semi-purified sweat antigen. Moreover, recombinant MGL_1304 abolished the binding of serum IgE of patients with AD to the semi-purified sweat antigen, or vice versa in immunoblot analysis, and attenuated the sensitization of RBL-48 mast cells expressing human FcɛRI by serum IgE. Studies of truncated mutants of MGL_1304 indicated that IgE of patients with AD recognized the conformational structure of MGL_1304 rather than short peptide sequences. Western blot analysis of the whole lysate, the culture supernatant of M globosa, and the semi-purified sweat antigen showed that MGL_1304 was produced as a minor immunological antigen of M globosa with posttranslational modification, cleaved, and secreted as a 17-kDa major histamine-releasing sweat antigen. CONCLUSION: MGL_1304 is a major allergen in human sweat and could cause type I allergy in patients with AD.

Elevated serum IgE against MGL_1304 in patients with atopic dermatitis and cholinergic urticaria.

BACKGROUND: MGL_1304 secreted by Malassezia globosa is contained in human sweat and induces histamine release from basophils in patients with atopic dermatitis (AD) at a high positive rate. The aims of this study were to establish the enzyme-linked immunosorbent assay (ELISA) measuring specific immunoglobulins against MGL_1304 and to investigate the levels of these immunoglobulins in sera of patients with various allergic diseases. METHODS: Purified MGL_1304 from human sweat (QRX) and recombinant MGL_1304 (rMGL_1304) were prepared for ELISA. To quantify the amount of MGL_1304-specific immunoglobulins, the standard serum was created by pooling sera of 20 patients with AD whose basophils released histamine in response to QRX. A monoclonal antibody which exhibited the highest neutralizing ability against QRX was established as Smith-2, and used as a capture antibody for the assay of QRX-specific IgE. A total of 156 subjects [normal controls (n = 23), AD (n = 63), cholinergic urticaria (CU) (n = 24), bronchial asthma (n = 32), and allergic rhinitis (n = 14)] were enrolled in this study. RESULTS: ELISA methods to quantify the specific IgE, IgG and IgG4 against MGL_1304 in sera were successfully established. Levels of QRX-specific IgE in sera of patients with AD and CU were significantly higher than those of normal controls. Moreover, the levels of QRX-specific IgE and rMGL_1304-specific IgE in patients with AD were significantly correlated with their disease severities. CONCLUSIONS: These ELISA methods to quantify the specific immunoglobulins against MGL_1304 are easy and useful means to assess allergy to MGL_1304. MGL_1304 contained in sweat is an important antigen for patients with AD and CU.

Application of SPR imaging sensor for detection of individual living cell reactions and clinical diagnosis of type I allergy.

A technique to visualize living cell activation in a real time manner without any labeling is required in the fields of life sciences and medicine. We have reported that surface plasmon resonance (SPR) sensors detect large changes of refractive index (RI) with living cells, such as mast cells, human basophils and lymphocytes. However conventional SPR sensors detect only an average change of RI with thousands of cells at detectable area on a sensor chip. Therefore, we developed an SPR imaging (SPRI) sensor with a CMOS camera and an objective lens in order to visualize RI of individual living cells and their changes upon stimuli. The SPRI sensor we developed could detect reactions of individual rat basophilic leukemia (RBL-2H3) cells and mouse keratinocyte cells in response to specific or nonspecific stimuli. Moreover, the sensor could detect the reactions of individual human basophils isolated from patients in response to antigens (allergens). Thus the technique can visualize the effect of various stimuli, inhibitors and/or conditions on cell reactions as change of intracellular RI distribution at single cell levels. Establishment of the technique to rapidly isolate cells from patient blood should enable us to utilize SPRI system as a high throughput screening system in clinical diagnosis, such as type I hypersensitivity and drug hypersensitivity, and as a tool to reveal novel phenomena in evanescent fields around plasma membranes.

The sensitivity and clinical course of patients with wheat-dependent exercise-induced anaphylaxis sensitized to hydrolyzed wheat protein in facial soap - secondary publication.

BACKGROUND: Recently, an increasing number of patients with wheat-dependent exercise-induced anaphylaxis (WDEIA) have been reported in Japan. Most of them had developed this condition during or after using hydrolyzed wheat protein (HWP)-containing soap (HWP-WDEIA). METHODS: To clarify the relation between WDEIA and HWP-containing soap and their prognosis, we retrospectively studied the patients who visited Hiroshima University Hospital and were diagnosed as WDEIA from January 2010 to June 2011. We took detailed clinical histories, performed skin prick tests, serum immunoassays for antigen-specific IgE and basophil histamine release test, and followed up their clinical courses after the diagnosis. RESULTS: Among 36 patients with WDEIA, 30 patients had used only one type of HWP-soap. The patients with HWP-WDEIA were mainly women and had developed facial symptoms and angioedema. They suffered from blood pressure reductions less frequently than patients with conventional WDEIA. The levels of gluten-specific IgE were higher than those of omega-5 gliadin in patients with HWP-WDEIA (P < 0.05, One-way ANOVA). All patients with HWP-WDEIA were positive against HWP in histamine release test. Among the conventional wheat antigens, glutenins induced the highest histamine release from basophils of patients with HWP-WDEIA. The sensitivities of patients against glutens and glutenins were reduced over months along with the discontinuance of HWP-soap. CONCLUSIONS: The development of HWP-WDEIA is associated with the use of HWP-soap. The sensitivity to HWP that cross reacts with non-processed wheat may be reduced or possibly cured after the discontinuation of HWP-soap.

Aspirin augments IgE-mediated histamine release from human peripheral basophils via Syk kinase activation.

BACKGROUND: Non-steroidal anti-inflammatory drugs (NSAIDs), especially aspirin, and food additives (FAs) may exacerbate allergic symptoms in patients with chronic idiopathic urticaria and food-dependent exercise-induced anaphylaxis (FDEIA). Augmentation of histamine release from human mast cells and basophils by those substances is speculated to be the cause of exacerbated allergic symptoms. We sought to investigate the mechanism of action of aspirin on IgE-mediated histamine release. METHODS: The effects of NSAIDs, FAs or cyclooxygenase (COX) inhibitors on histamine release from human basophils concentrated by gravity separation were evaluated. RESULTS: Benzoate and tartrazine, which have no COX inhibitory activity, augmented histamine release from basophils similar to aspirin. In contrast, ibuprofen, meloxicam, FR122047 and NS-398, which have COX inhibitory activity, did not affect histamine release. These results indicate that the augmentation of histamine release by aspirin is not due to COX inhibition. It was observed that aspirin augmented histamine release from human basophils only when specifically activated by anti-IgE antibodies, but not by A23187 or formyl-methionyl-leucyl-phenylalanine. When the IgE receptor signaling pathway was activated, aspirin increased the phosphorylation of Syk. Moreover, patients with chronic urticaria and FDEIA tended to be more sensitive to aspirin as regards the augmentation of histamine release, compared with healthy controls. CONCLUSIONS: Aspirin enhanced histamine release from basophils via increased Syk kinase activation, and that the augmentation of histamine release by NSAIDs or FAs may be one possible cause of worsening symptoms in patients with chronic urticaria and FDEIA.

Japanese guidelines for diagnosis and treatment of urticaria in comparison with other countries.

Several guidelines for urticaria and angioedema have been published in Europe and United States since 1997. General principles for diagnosis and treatments of them are similar. However, each guideline has its own characteristics and shows differences in areas such as the coverage of urticaria subtypes, nomenclatures, and hierarchy of the medications. In Japan, the Japanese Dermatological Association (JDA) published its first guideline for urticaria and angioedema in 2005. It established a new classification of urticaria and angioedema together with the definition of each subtype. It emphasized the importance of discriminating idiopathic urticaria, consisting of acute urticaria and chronic urticaria from inducible urticaria, such as allergic urticaria, physical urticaria and cholinergic urticaria. It contains several unique algorithms for diagnosis and treatment of urticaria from a view point of clinical practices, and was further enforced by a style of EBM in 2011. Nevertheless, these guidelines have not been recognized outside of Japan, because of a language barrier. In this article, the outline of the newest guidelines by JDA are introduced and compared with the guidelines in other countries published in English.

A survey on subtypes and clinical characteristics of 1061 patients with urticaria in the primary care institutes in Japan.

The prevalence of urticaria has been reported mostly in Europe and North America. However, precise information regarding its subtypes and clinical characteristics in primary care practice, especially in Asian countries, are scant. Patients with urticaria and/or angioedema who visited nine primary clinics of accredited dermatologists and allergologists in Japan were recruited from October to November 2020. The information of age, sex, disease duration, urticaria control test (UCT), and concomitant urticaria subtypes were collected. A total of 1061 patients participated. The number of patients was high in the 20 to 50 age groups with a peak in the 40s. The most frequent urticaria subtype was chronic spontaneous urticaria (CSU) followed by dermographism, acute spontaneous urticaria (ASU), angioedema, and cholinergic urticaria (CholU) (66.8%, 22.7%, 18.9%, 14.1% and 5.7% in all patients with urticaria). CSU development increased with age from the 20s to 50s, especially in females. Dermographism had a peak in the 40s. ASU had bimodal peaks in childhood and in the 30s. CholU was common in males in the 10-20s. Most angioedema patients were female with an increase in their 30s. Angioedema was solely present in 14 of 1061 participants (1.3%), while 136 (12.8%) had angioedema concomitant with urticaria. UCT showed poorly controlled urticaria with lower scores in patients with concomitant CSU and other subtypes than in those with CSU alone. Urticaria tends to develop in young to middle-aged females. The most common urticaria subtype is CSU, while the number of patients with CholU is high and that of angioedema is low in Japan.

[The sensitivity and clinical course of patients with wheat-dependent exercise-induced anaphylaxis sensitized to hydrolyzed wheat protein in facial soap].

BACKGROUND: Recently an increasing number of patients with wheat-dependent exercise-induced anaphylaxis (WDEIA), developed during or after using hydrolyzed wheat protein (HWP)-containing soap (HWP-WDEIA), were reported in Japan. METHODS: To clarify the relation between WDEIA and HWP-containing soap and their prognosis, we investigated the patients who visited Hiroshima University Hospital and were diagnosed as WDEIA from January 2010 to June 2011. We took detailed clinical histories, performed skin prick tests, serum immunoassays for antigen-specific IgE and basophil histamine release test, and followed up their clinical courses after the diagnosis. RESULTS: Among 36 patients with WDEIA, 30 patients had used only one type of HWP-soap. The patients with HWP-WDEIA were mainly women and had developed facial symptoms and angioedema. They suffered from blood pressure reductions less frequently than patients with conventional WDEIA. The levels of glutens-specific IgE were higher than those of ω-5 gliadin in patients with HWP-WDEIA (p<0.05, One-way ANOVA). All patients with HWP-WDEIA were positive against HWP in histamine release test. Among the conventional wheat antigens, glutenins induced highest histamine release from basophils of patients with HWP-WDEIA. The sensitivities of patients against glutens and glutenins were reduced over months along with the discontinuance of HWP-soap. CONCLUSIONS: The development of HWP-WDEIA is associated with the use of HWP-soap. The sensitivities to HWP that cross reacts with non-processed wheat may be reduced or possibly cured after the discontinuation of HWP-soap.

Peritoneal injection of fucoidan suppresses the increase of plasma IgE induced by OVA-sensitization.

We previously reported that fucoidan, a dietary fiber purified from seaweed, inhibited IgE production by B cells in vitro. In this study, we examined the effect of fucoidan on IgE production in vivo. The OVA-induced increase of plasma IgE was significantly suppressed when fucoidan was intraperitoneally, but not orally, administered prior to the first immunization with OVA. The production of IL-4 and IFN-gamma in response to OVA in spleen cells isolated from OVA-sensitized mice treated with fucoidan in vivo was lower than that from mice treated without fucoidan. Moreover, the flow cytometric analysis and ELISpot assay revealed that the administration of fucoidan suppressed a number of IgE-expressing and IgE-secreting B cells, respectively. These results indicate that fucoidan inhibits the increase of plasma IgE through the suppression of IgE-producing B cell population, and the effect of fucoidan in vivo is crucially dependent on the route and timing of its administration.

Surface plasmon resonance biosensor detects the downstream events of active PKCbeta in antigen-stimulated mast cells.

Surface plasmon resonance (SPR) biosensors detect large changes of angle of resonance (AR) when RBL-2H3 mast cells are cultured on a sensor chip and stimulated with antigen. However, the detail of molecular events that are responsible for such large changes of AR remained unknown. In this study, we investigated the relationship between intracellular signaling events induced by antigen and the change of AR, by genetic manipulation of intracellular signaling molecules; spleen tyrosine kinase (Syk), src-like adaptor protein (SLAP), linker for activation of T cells (LAT), growth-factor-receptor-bound protein 2 (Grb2), Grb2-related adaptor protein (Gads), and isotypes of protein kinase C (PKC). RBL-2H3 mast cells overexpressing dominant-negative Syk or SLAP, which both interfere with active Syk, exhibited only minimal increase of AR in response to antigen stimulation. Likewise, the interference of the activation of LAT and Gads, by expressing dominant-negative LAT and Gads, respectively, resulted in nearly complete suppression of the antigen-induced increase of AR. The cells overexpressing PKCs, apart from PKCbeta, showed a reduced extent of increase of AR in response to antigen stimulation. Moreover, the introduction of the small interfering RNA targeted against PKCbeta suppressed the antigen-induced increase of AR. These results indicate that the activation of Syk, LAT, Gads, and subsequent PKCbeta is indispensable for the antigen-induced increase of AR of mast cells detected by SPR biosensors.

[Taking showers at school is beneficial for children with severer atopic dermatitis].

BACKGROUND: Sweat(ing) is a common aggravating factor of atopic dermatitis (AD), and many school children with AD experience the exacerbation of their disease in summer. OBJECTIVE: We evaluated the usefulness of taking shower at the school for the management of AD in summer. METHODS: Fifty-eight school children with moderate or severer atopic dermatitis were enrolled in the study. Subjects were allocated to one of following groups, group A: no shower (n=15), group B: 4-weeks shower (n=22), group C1: 2-weeks shower in the first half (n=11), or group C2: 2-weeks shower in the latter half (n=10), and took (or did not take) shower at the school from the beginning of September. Disease severity was evaluated on day 0, 2 weeks later and 4 weeks later using SCORAD scoring system. RESULTS: Significant improvements in SCORAD scores after 4 weeks were observed only in groups B and C1. When the subjects were sub-divided by the severity of the disease, the significant effect of shower was limited to the patients with severe and most severe disease. Similar results were obtained with a modified SCORAD score in which subjective symptoms were excluded. CONCLUSION: It is useful to take showers at the school for the management of AD for the children with severer disease.