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The inflammatory response after myocardial infarction (MI) is a precisely regulated process that greatly affects subsequent remodeling. Here, we show that basophil granulocytes infiltrated infarcted murine hearts, with a peak occurring between days 3 and 7. Antibody-mediated and genetic depletion of basophils deteriorated cardiac function and resulted in enhanced scar thinning after MI. Mechanistically, we found that basophil depletion was associated with a shift from reparative Ly6Clo macrophages toward increased numbers of inflammatory Ly6Chi monocytes in the infarcted myocardium. Restoration of basophils in basophil-deficient mice by adoptive transfer reversed this proinflammatory phenotype. Cellular alterations in the absence of basophils were accompanied by lower cardiac levels of IL-4 and IL-13, two major cytokines secreted by basophils. Mice with basophil-specific IL-4/IL-13 deficiency exhibited a similarly altered myeloid response with an increased fraction of Ly6Chi monocytes and aggravated cardiac function after MI. In contrast, IL-4 induction in basophils via administration of the glycoprotein IPSE/α-1 led to improved post-MI healing. These results in mice were corroborated by the finding that initially low counts of blood basophils in patients with acute MI were associated with a worse cardiac outcome after 1 year, characterized by a larger scar size. In conclusion, we show that basophils promoted tissue repair after MI by increasing cardiac IL-4 and IL-13 levels. [ABSTRACT FROM AUTHOR]

While opioids represent one of the most common medication allergy labels, these labels are often unsubstantiated in clinical practice. The removal of erroneous opioid allergy labels has a unique importance in the population with acute or chronic pain. The current approach to patients with pseudo-allergy to opioids is switching to an alternative opioid with less histamine release. Thus, allergy labels to relatively lower potency opioids such as codeine may be feasibly result in the prescription of stronger medications like fentanyl that would otherwise not be indicated. This narrative review provides an overview of the epidemiology and clinical manifestations of opioid allergy labels commonly encountered by pain management practitioners along with recommendations for evaluation and management. A literature search of PubMed was performed using the comprehensive MeSH term, "Opioid Allergy". In recent years, it has become apparent that a substantial proportion of patients labeled as opioid allergic are found to be tolerant of these agents. Opioid skin testing and IgE assays are of limited application. DPT is the yet underutilized gold standard for diagnosis. There is also an increasing call for studies evaluating basophil activation testing in opiate allergy. Opioid allergy labels require a closer look especially in view of the current opioid epidemic. The low likelihood of true reactivity, combined with the conceivable clinical relevance of an opioid allergy label, calls for further characterization of this label in populations with acute or chronic pain diagnoses. Future directions should include larger prospective studies with systematic evaluation and classification of opioid allergy labels to determine future viability of opioid use. EHR electronic health record NMBA neuromuscular blocking agent IgE immunoglobulin E MC mast cell GPCR G-protein coupled receptor MRGPRX2 mas-related G-protein receptor QAI quaternary ammonium ions SCAR severe cutaneous adverse reaction AGEP acute generalized exanthematous pustulosis SDRIFE symmetrical drug-related intertriginous and flexural exanthema BAT basophil activation testing DPT drug provocation testing [ABSTRACT FROM AUTHOR]

The article presents the study of Harlequin cells (HQ) has called hybrid eosinophilic basophilic precursors, are cells harbouring both eosinophilic and basophilic granules in the cytoplasm. It mentions that the cells ubiquitously present among many bone marrow aspirates (BMA) without any clonal myeloid neoplasm, cells do not extensively studied with paucity of available literature, and the BMA has submitted between the period September 1, 2018-September 30, 2018 at Laboratory Oncology Unit.

Basophils and mast cells share some features, including basophilic granules in the cytoplasm, cell surface expression of the high-affinity IgE receptor and release of chemical mediators such as histamine. Because of this similarity and their minority status, basophils had often been erroneously considered as minor relatives or blood-circulating precursors of tissue-resident mast cells, and therefore long been neglected or underestimated in immunological studies. Taking advantage of newly developed tools, such as basophil-depleting antibodies and engineered mice deficient for only basophils, recent studies have identified previously unappreciated roles for basophils, distinct from those played by mast cells, in allergic responses, protective immunity against parasitic infections and regulation of other immune cells. In this review, we focus on two topics that we presented and discussed in the 46th Annual Meeting of the Japanese Society for Immunology held in Sendai in December 2017. The first topic is the function of basophils as antigen-presenting cells for driving Th2 cell differentiation. We demonstrated that basophils produce few or no MHC class II (MHC-II) proteins by themselves although they can acquire peptide–MHC-II complexes from dendritic cells through trogocytosis, and present them and provide IL-4 to naive CD4 T cells, promoting Th2 cell differentiation. The second topic is the basophil-specific effector molecules involved in allergic responses. Among mouse mast cell proteases (mMCPs), mMCP-8 and mMCP-11 are expressed almost exclusively by basophils. Analyses in vitro and in vivo revealed that both proteases can induce leukocyte migration through distinct mechanisms, contributing to the development of basophil-dependent allergic inflammation. [ABSTRACT FROM AUTHOR]

Summary: Background: The prevalence of sesame food allergy (SFA) has increased over recent years, with the potential of anaphylactic reactions upon exposure. Oral food challenge (OFC) remains the diagnostic standard, yet its implementation may be risky. Commercial skin prick tests (SPT) have a low sensitivity. Investigation of alternate diagnostic methods is warranted. Objective: To evaluate the utility of SPT and the basophil activation test (BAT) for SFA diagnosis. Methods: Eighty‐two patients with suspected SFA completed an open OFC to sesame or reported a recent confirmed reaction. Patients were administered skin prick tests (SPT) with commercial sesame seed extract (CSSE) and a high protein concentration sesame extract (HPSE) (100 mg/mL protein). Whole blood from 80 patients was stimulated with sesame seed extract (40‐10 000 ng/mL protein) for BAT), assessing CD63 and CD203c as activation markers. Results: Sixty patients (73%) had IgE‐mediated reactions to sesame, and 22 (27%) did not react. Receiver operating characteristic (ROC) curve analysis demonstrated an area under the curve (AUC) of 0.87 for HPSE‐SPT and 0.66 for CSSE‐SPT. At 1000 ng/mL of sesame protein, induction of CD63 and CD203c was weakly but significantly associated with OFC eliciting dose by rank (Spearman's rho = −.42 (P < .01) and −.35 (P < .05) for CD63 and CD203c, respectively). By ROC analysis, the AUC was 0.86 for CD63 and was 0.81 for CD203c sesame‐induced basophil expression. Using HPSE‐SPT as a first test to definitively diagnose (n = 24) or rule‐out (n = 5) SFA and BAT as a second test to diagnose the remainder results in the correct classification of 73 of 80 (91%) patients, leaving one false negative and 4 false positive patients. Two BAT non‐responders remain unclassified by this algorithm. Conclusions & Clinical Relevance: While prospective cohort validation is necessary, joint utilization of BAT and SPT with HPSE extract may obviate the need for OFC in most SFA patients. [ABSTRACT FROM AUTHOR]

Summary: Background: In humans, both basophils and dendritic cells (DCs) express the high‐affinity IgE receptor (FcεRI). Objective: To gain more insight into the relation between serum IgE levels and FcεRI expression and IgE binding by DCs and basophils in house dust mite (HDM) allergy and during subcutaneous immunotherapy (SCIT). Methods: We measured FcεRI, IgE and HDM allergen on DCs (conventional type 2 DCs, cDC2s; plasmacytoid dendritic cells, pDCs) and basophils by flow cytometry in 22 non‐allergic vs 52 allergic subjects and upon HDM SCIT in 28 allergic subjects. IgE levels were measured in serum. Results: Serum IgE correlated differentially with FcεRI expression and IgE binding depending on cell type and allergic status. In non‐allergic subjects, FcεRI/IgE surface densities increased with serum IgE to a significantly stronger degree on basophils compared to cDC2s. By contrast, in allergic subjects FcεRI/IgE surface densities increased with serum IgE to a slightly stronger degree on cDC2s compared to basophils. In addition, the data set suggests sequential loading of IgE onto FcεRI expressed by these cells (basophils>cDC2s>pDCs). Finally, HDM SCIT induced a temporary increase in serum IgE, which was paralleled by a peak in FcεRI and IgE on DCs, but not on basophils. Conclusions & Clinical Relevance: This study provides a comprehensive insight into the relation between serum IgE and FcεRI/IgE on basophils and DC subsets. The novel finding that HDM SCIT induces a temporary increase in FcεRI expression on DCs, but not on basophils, can be an incentive for future research on the potential tolerogenic role of IgE/FcεRI signalling in DCs in the setting of allergen immunotherapy. [ABSTRACT FROM AUTHOR]

Ticks are blood-feeding arthropods that can transmit pathogens to humans and animals, leading to serious infectious diseases such as Lyme disease. After single or multiple tick infestation, some animal species develop resistance to tick feeding, leading to reduced risk of pathogen transmission. In mice infested with larval Haemaphysalis longicornis ticks, both mast cells and basophils reportedly play key roles in the manifestation of acquired tick resistance (ATR), but it remains ill-defined how they contribute to it. Here, we investigated their products responsible for ATR. Treatment of mice with antihistamine abolished the ATR while histamine or histamine H1 receptor agonist reduced tick-feeding even in the first infestation. In accordance with these, mice deficient for histamine production showed little or no ATR, indicating the crucial role for histamine in the expression of ATR. Adoptive transfer of mast cells and basophils derived from histamine-sufficient or deficient mice to recipient mice lacking mast cells and basophils, respectively, revealed that histamine produced by basophils but not mast cells is essential for the manifestation of ATR, in contrast to the case of local and systemic anaphylaxis where mast cell-derived histamine is the major player. During the second but not first tick infestation, basophils accumulated and made a cluster, surrounding a tick mouthpart, in the epidermis whereas mast cells were scattered and localized mainly in the dermis, more distantly from a tick mouthpart. This appears to explain why basophil-derived histamine is much more effective than mast cell-derived one. Histamine-sufficient, but not -deficient mice showed the thickened epidermis at the second tick-feeding site. Taken together, histamine released from skin-infiltrating basophils rather than skin-resident mast cells plays a crucial role in the manifestation of ATR, perhaps through promotion of epidermal hyperplasia that may inhibit tick feeding. [ABSTRACT FROM AUTHOR]

Background: Basophilic granulocytes (BGs) not only initiate the induction of Th2 cell differentiation, but also amplify the ongoing Th2 response. Shuang-Huang-Lian (SHL) is clinically used for relieving type I hypersensitivity by continuous treatment for several weeks. Methods: ELISA, flow cytometry, magnetic activated cell sorting, isoelectric precipitation, hybridoma technique, transfection and luciferase reporter assay were used in this study. The statistical analysis was performed using a one-way ANOVA. Results: Our recently published study demonstrated that SHL exerted a remarkable effect on mast cell stabilization. Herein, we sought to elucidate the effect of SHL on shrimp tropomyosin (ST)-induced Th2 immunity and its underlying mechanisms. The obtained data showed that continuous treatment with SHL significantly suppressed ST-stimulated Th2-cytokines release and IgE synthesis. A mechanistic study indicated that SHL not only reduced BG early IL-4 release before ST-specific IgE (sIgE) production, but also inhibited BG activation in the presence of sIgE, including suppressing CD200R surface expression and decreasing IL-4 production. Moreover, SHL markedly decreased the cytosolic Ca2+ (Ca[c]2+) level and inhibited the nuclear factor of activated T cells (NFAT) activation in RBL-2H3 cells. Conclusions: Collectively, SHL potently reduces ST-induced Th2 immunity by inhibiting the BG Ca2+-NFAT pathway and, thus, suppressing the early IL-4 release before sIgE synthesis and inhibiting BG activation in the presence of sIgE. This study provides the pharmacological basis for the clinical use of SHL to relieve type I hypersensitivity by a successive dose regimen. [ABSTRACT FROM AUTHOR]

Background P2Y purinergic receptors (P2YR) are G protein-coupled receptors that are stimulated by extracellular nucleotides. They mediate cellular effects by regulating cAMP production, protein kinase C activation, inositol trisphosphate generation, and Ca 2+ release from intracellular stores. The P2Y6 receptor of this family is selectively stimulated by UDP, and selectively inhibited by MRS2578. In the present study, we examined the effect of UDP/P2Y6 receptor signaling on IgE-dependent degranulation in human basophils. Methods Basophils were purified from human peripheral blood. The mRNA expression of genes encoding P2YR and ecto-nucleoside triphosphate diphosphohydrolase (ENTPDase) was measured by RT-PCR. Intracellular Ca 2+ influx via UDP/P2Y6 receptor signaling in basophils was detected using a calcium probe. The effect of UDP/P2Y6 receptor signaling on IgE-dependent degranulation in basophils was confirmed by measuring CD63 expression by flow cytometry. Autocrine secretion of nucleotides was detected by HPLC analysis. Results We showed that purified basophils express P2Y6 mRNA and that UDP increased intracellular Ca 2+ , which was reduced by MRS2578 treatment. UDP promoted IgE-dependent degranulation. Furthermore, MRS2578 inhibited IgE-dependent degranulation in basophils. HPLC analysis indicated that basophils spontaneously secrete UTP. In addition, basophils expressed the extracellular nucleotide hydrolases ENTPDase2, ENTPDase3, and ENTPDase8. Conclusions This study showed that UDP/P2Y6 receptor signaling is involved in the regulation of IgE-dependent degranulation in basophils, which might stimulate the P2Y6 receptor via the autocrine secretion of UTP. Thus, this receptor represents a potential target to regulate IgE-dependent degranulation in basophils during allergic diseases. [ABSTRACT FROM AUTHOR]

The strawberry fruit Fra a 1-proteins are homologues of the major birch pollen allergen Bet v 1 and have essential biological functions in pigment formation during fruit ripening. Patients affected by allergy against birch pollen tolerated fruits of a naturally occurring white-fruited F . × ananassa genotype, which showed reduced levels of Fra a 1 proteins along with enzymes of the anthocyanin pigment pathway. We evaluated the cross-reactive allergenic potential of a number of naturally occurring white- and red-fruited strawberry varieties to detect genotypes with low allergenic reactivity, whose fruit might be tolerated by patients with mild allergy. Protein extracts of 51 different strawberry varieties ( Fragaria × ananassa , F . vesca , and F . nilgerensis ) were screened by Western blot analysis with a polyclonal Fra a 1.02 antibody. Besides, activation of basophils of eight atopic patients allergic to birch pollen were studied using Bet v 1a and different concentrations of 15 selected strawberry protein extracts out of the 51 strawberry genotypes. Median percentages of activated basophils stimulated by extracts from white- and red-fruited genotypes ranged from 36 to 84% and 44 to 76%, respectively indicating that white-fruited strawberry are not per se hypoallergenic. Protein extracts from white-fruited F . vesca cv. Yellow Wonder showed the lowest cross-reactivity but high biological variability. The knowledge about the allergenic potential of different strawberry genotypes may help to improve food safety and can serve as starting point for the development of red-fruited hypoallergenic strawberry cultivars. [ABSTRACT FROM AUTHOR]

The prevalence of food allergies worldwide has increased recently. Epicutaneous sensitization to antigen could be a method to study food allergy. To clarify the mechanisms of food allergy, we established a mouse model of epicutaneous sensitization using ovalbumin ( OVA). BALB/c mice were sensitized by three-time application of OVA to tape-stripped skin (1-week sensitization at 2-week intervals) and oral challenge of OVA undertaken. Rectal temperature was monitored. Blood and tissue (skin and jejunum) of challenged mice were taken. Numbers of mast cells ( MCs) and basophils were counted. Serum and/or tissue levels of OVA -specific IgE and IgG antibodies and several cytokines were measured using enzyme-linked immunoassay kits. MC and basophil depletion experiments were undertaken. In OVA/epicutaneous-sensitized and orally challenged mice, systemic anaphylaxis (as evidenced by reduced rectal temperature) was observed. Levels of OVA-specific IgE and IgG antibodies were increased in these mice, as were increased number of MCs and basophils. Serum levels of MC protease 1 were increased significantly. Basophil and MC depletion experiments revealed that they both participate in reactions. Increased production of thymic stromal lymphopoietin ( TSLP) at skin sites of OVA sensitization was noted. We speculate that TSLP produced from epidermal cells during antigen sensitization can enable basophils to promote a T helper (Th)2 immune reaction, leading to and systemic anaphylaxis by antigen-specific IgE-bearing MCs. This TSLP-basophils- MC axis could be a novel therapeutic target against food allergy. [ABSTRACT FROM AUTHOR]

Background: A general understanding of allergic transfusion reaction mechanisms remains elusive. Multiple mechanisms have been proposed, but none have been compared experimentally.Study Design and Methods: We used histamine release (HR) from healthy human donor basophils to model allergic transfusion reactions. Platelet component supernatant (plasma), platelet lysate, and manipulated platelet lysates (dialyzed, delipidated, trypsinized, mild heat-inactivated, and ultracentrifuged) were used to characterize allergic stimuli. Immunoglobulin-dependent mechanisms were investigated through cell surface immunoglobulin depletion and ibrutinib signaling inhibition. HR induced by platelet mitochondria was compared with HR by platelet lysate with or without DNase treatment.Results: Robust, dose-responsive HR to platelet lysate was observed in two of eight nulliparous, never-transfused, healthy donors. No HR was observed with plasma. Among manipulated platelet lysates, only trypsin treatment significantly reduced HR (39% reduction; p = 0.008). HR in response to platelet lysate significantly decreased with either cell surface immunoglobulin depletion or ibrutinib pretreatment. Platelet mitochondria induced minimal basophil HR, and DNase treatment did not inhibit platelet lysate-induced HR.Conclusion: Type I immediate hypersensitivity to platelet proteins may be an allergic transfusion reaction mechanism. Prior sensitization to human proteins is not required for basophil responses to platelet proteins. Further study into the relative contributions of hypersensitivity to platelet versus plasma proteins in transfusion is warranted. [ABSTRACT FROM AUTHOR]

Being discovered long ago basophils have been neglected for more than a century. During the past decade evidence emerged that basophils share features of innate and adaptive immunity. Nowadays, basophils are best known for their striking effector role in the allergic reaction. They hence have been used for establishing new diagnostic tests and therapeutic approaches and for characterizing natural and recombinant allergens as well as hypoallergens, which display lower or diminished IgE-binding activity. However, it was a long way from discovery in 1879 until identification of their function in hypersensitivity reactions, including adverse drug reactions. Starting with a historical background, this review highlights the modern view on basophil biology. [ABSTRACT FROM AUTHOR]

The article discusses application of basophil activation test (BAT) in determining food allergy and analyzing reliability of the CD123-endowed BAT. Topics discussed include using flow cytometry (FC) to capture activity of basophils, operating phenotyping protocol with applying CD63 and CD203c as activation markers and diagnosing food allergy.

Summary Crosslinking of the immunoglobulin receptor FcεRI activates basophils and mast cells to induce immediate and chronic allergic inflammation. However, it remains unclear how the chronic allergic inflammation is regulated. Here, we showed that ecto-nucleotide pyrophosphatase-phosphodiesterase 3 (E-NPP3), also known as CD203c, rapidly induced by FcεRI crosslinking, negatively regulated chronic allergic inflammation. Basophil and mast cell numbers increased in Enpp3 −/− mice with augmented serum ATP concentrations. Enpp3 −/− mice were highly sensitive to chronic allergic pathologies, which was reduced by ATP blockade. FcεRI crosslinking induced ATP secretion from basophils and mast cells, and ATP activated both cells. ATP clearance was impaired in Enpp3 −/− cells. Enpp3 −/− P2rx7 −/− mice showed decreased responses to FcεRI crosslinking. Thus, ATP released by FcεRI crosslinking stimulates basophils and mast cells for further activation causing allergic inflammation. E-NPP3 decreases ATP concentration and suppresses basophil and mast cell activity. [ABSTRACT FROM AUTHOR]

Without effective therapy, chronic-phase chronic myeloid leukemia (CP-CML) evolves into an acute leukemia (blast crisis [BC]) that displays either myeloid or B-lymphoid characteristics. This transition is often preceded by a clinically recognized, but biologically poorly characterized, accelerated phase (AP). Here, we report that IKAROS protein is absent or reduced in bone marrow blasts from most CML patients with advanced myeloid disease (AP or BC). This contrasts with primitive CP-CML cells and BCR-ABL1-negative acute myeloid leukemia blasts, which express readily detectable IKAROS. To investigate whether loss of IKAROS contributes to myeloid disease progression in CP-CML, we examined the effects of forced expression of a dominant-negative isoform of IKAROS (IK6) in CP-CML patients' CD34(+) cells. We confirmed that IK6 disrupts IKAROS activity in transduced CP-CML cells and showed that it confers on them features of AP-CML, including a prolonged increased output in vitro and in xenografted mice of primitive cells with an enhanced ability to differentiate into basophils. Expression of IK6 in CD34(+) CP-CML cells also led to activation of signal transducer and activator of transcription 5 and transcriptional repression of its negative regulators. These findings implicate loss of IKAROS as a frequent step and potential diagnostic harbinger of progressive myeloid disease in CML patients. [ABSTRACT FROM AUTHOR]

Anaphylaxis is an unanticipated, acute, and sometimes life-threatening systemic reaction with variable clinical presentations that is typically mediated by immunoglobulin E and causes degranulation of mast cells and basophils. The onset of symptoms can occur within minutes or hours after exposure to a known or suspected trigger, and reactions sometimes progress very rapidly, which can lead to death. One trigger of anaphylaxis in younger adults is moderately intense physical exercise, which has been termed exercise-induced anaphylaxis (EIA). Although rare, EIA should be recognized as a distinct and potentially life-threatening form of physical allergy, and is often undetected or inadequately treated. The ingestion of specific foods, including seafood, tree nuts, and wheat, or a nonspecific meal consisting of multiple food components shortly before or after physical exertion, is sometimes, but not always, the principal precipitant of EIA. This article briefly explores the current hypotheses on the role of immunoglobulin E, response mediators, and physiologic changes that bring on EIA, and discusses the current recommendations for diagnosis, including allergen challenge and laboratory testing, emergency care, and long-term prevention and patient follow-up. Accurate diagnosis of EIA is critical to providing lifesaving therapy and care plans to patients at risk. With respect to the medical management of EIA, mainstay therapy with epinephrine is described. For those with a known history of EIA, a comprehensive anaphylaxis action plan is central to successful patient management. Furthermore, patient education is necessary to heighten awareness of the signs and symptoms of EIA and appropriate strategies for allergen avoidance and self-management of anaphylactic episodes with self-injectable epinephrine. [ABSTRACT FROM AUTHOR]

The roles of basophils, TSLP and IL-33 in food allergy following epicutaneous sensitizationCutaneous sensitization with a food antigen before its consumption elicits the development of food allergy. Here, we report the site- and stage-dependent roles of basophils and proallergic cytokines, thymic stromal lymphopoietin (TSLP) and IL-33, in a mouse model of food allergy initially sensitized cutaneously with the food antigen. Mice were epicutaneously sensitized with the food antigen ovalbumin (OVA) followed by oral challenge with OVA. Epicutaneously sensitized mice produced OVA-specific IgE and developed IgE-dependent anaphylaxis after oral challenge. Basophil-depleted or TSLP–receptor-deficient mice did not produce OVA-specific IgE and were protected from oral challenge-induced anaphylaxis. IL-33-deficient mice produced normal levels of OVA-specific IgE. However, IL-33-deficient mice and mice treated with recombinant soluble IL-33 receptor were protected from anaphylaxis. Thus, basophils and TSLP have pivotal roles in Th2 development in the skin during the sensitization phase of food allergy. In contrast, while IL-33 is dispensable for promoting cutaneous antigen sensitization, the cytokine is essential for inducing IgE-dependent anaphylaxis in the gut. [ABSTRACT FROM AUTHOR]

Many techniques are being used to examine the status of circulating human basophils including the enhanced expression of a variety of cell surface proteins. There is accumulating evidence that there are at least two compartments containing these activation marker proteins but there are only some indications for the signaling requirements for each of the compartments. This study began with published reports by other investigators who potentially dissociated CD63 expression from anaphylactic degranulation with the p38 inhibitor, SB203580, a possible falsification of a previously proposed hypothesis regarding CD63 expression. To explore the signaling requirements for CD63, a variety of pharmacological agents were used to inhibit or enhance 4 endpoints of basophil activation. First, it was found that inhibition of both histamine release and CD63 expression with SB203580 was concordant. But it was also found that this agent had no effect on increased expression of CD203c and CD11b. Actin polymerization inhibitors caused marked enhancement of CD63 expression (concordant with their effects on degranulation) with no effect on expression of CD203c and CD11b. The third generation syk inhibitor, NVP-QAB205, showed a 5-fold lower potency for inhibiting expression of CD203c and CD11b than for CD63. Finally, while desensitization of CD11b and CD203c expression occurs, it is slower than desensitization of the CD63 response. Taken together, these various observations demonstrate a marked difference in the early signaling requirements for the CD11b/CD203c compartment and CD63 degranulation and provide support for the hypothesis that CD11b and CD203c reside in a similar compartment. Copyright © 2012 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Abstract: Background: Stimulated human basophils exhibit different degranulation patterns with release of mediators and appearance of activation markers such as CD63 and CD203c. Traditionally, released mediators are quantified in the supernatant of activated cells, whereas the expression of activation markers by individual cells is analyzed by flow cytometry. Alternatively, intracellular histamine and its release by basophils and mast cells have been repeatedly studied applying an enzyme-affinity-gold method based on the affinity of the histaminase diamine oxidase for its substrate histamine. Objective: To develop a flow cytometric technique enabling to study histamine release by individual basophils in combination with the expression of activation markers. To elucidate the principles of basophil degranulation on a single cell level. Methods: Intracellular histamine and its release is analyzed flow cytometrically by an enzyme-affinity method using diamine oxidase conjugated to laser-excitable fluorochromes. Phenotyping of cells implied flow cytometric quantification of CD63 and CD203c. Stimuli such as allergen, anti-IgE, N-formyl-met-leu-phe (fMLP), phorbol 12-myristate 13-acetate (PMA), ionomycin and interleukin (IL-)3 are applied to obtain different degranulation profiles. Results: Stimulation with anti-IgE, allergen, fMLP and PMA±ionomycin induces a rapid release of histamine that can be analyzed flow cytometrically. Analyses on a single cell level reveal that histamine release is not restricted to cells showing significant up-regulation of CD63. Alternatively, up-regulation of CD203c does not per se indicate histamine release. In some patients, priming of cells with IL-3 not only facilitates basophil responsiveness but also implies an increased ability of DAO to label the cells. Conclusion: This study provides the proof-of-concept that histamine and its release can be studied by multicolor flow cytometry on a single cell level (HistaFlow). Coupling the data to simultaneous phenotyping of activated basophils confirms that histamine release principally results from anaphylactic degranulation and in a lesser extent from piecemeal degranulation. [Copyright &y& Elsevier]

Rationale: Basophils contribute to anaphylaxis and allergies. We examined the utility of assessing basophil-associated surface antigens (CD11b/CD63/CD123/CD203c/CD294) in characterizing and monitoring subjects with nut allergy. Methods: We used flow cytometry to analyze basophils at baseline (without any activation) and after ex vivo stimulation of whole blood by addition of nut or other allergens for 2, 10, and 30 min. We also evaluated whether basophil expression of CD11b/CD63/CD123/CD203c/CD294 was altered in subjects treated with anti-IgE monoclonal antibody (omalizumab) to reduce plasma levels of IgE. Results: We demonstrate that basophil CD203c levels are increased at baseline in subjects with nut allergy compared to healthy controls (13 subjects in each group, p < 0.0001). Furthermore, we confirm that significantly increased expression of CD203c occurs on subject basophils when stimulated with the allergen to which the subject is sensitive and can be detected rapidly (10 min of stimulation, n = 11, p < 0.0008). In 5 subjects with severe peanut allergy, basophil CD203c expression following stimulation with peanut allergen was significantly decreased (p < 0.05) after 4 and 8 weeks of omalizumab treatment but returned toward pretreatment levels after treatment cessation. Conclusions: Subjects with nut allergy show an increase of basophil CD203c levels at baseline and following rapid ex vivo stimulation with nut allergen. Both can be reduced by omalizumab therapy. These results highlight the potential of using basophil CD203c levels for baseline diagnosis and therapeutic monitoring in subjects with nut allergy. Copyright © 2010 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate how does an acute 4-week submaximal exercise affect both leukocyte and leukocyte subgroups. The study registered 8 healthy male subjects. The subjects were exercised on Monark 814-E and 818 model ergometric bicycles 3 times a week for 4 weeks at above threshold heart rate and 75% of Max VO_{2}. Blood samples were collected three times from the subjects, before starting the exercise, immediately after finishing the last exercise and 2 hours after the last exercise. The samples were analyzed in HemaCell Counter (Skits) apparatus to quantify leukocyte, neutrophil, monocyte, eosinophil and basophil levels. Leukocyte counts obtained in both post-exercise measurements were significantly higher than those before the exercise (p< 0.05). Neutrophil percentages two hours after exercise were higher than those before and immediately after exercise (p< 0.05). Lymphocyte percentages obtained just after exercise were elevated in comparison to those both before and two hours after exercise (p< 0.05). However, lymphocyte percentages two hours after exercise were significantly lower than the pre- and post-exercise percentages (p< 0.05). Percentages of monocytes, eosinophils and basophils in both post-exercise measurements were lower relative to pre-exercise values (p<0.05). In conclusion both acute and 4-week submaximal exercise have significant effects on leukocyte and leukocyte subgroups. [ABSTRACT FROM AUTHOR]

Background Activation of human basophils results in the release of many different mediators and the expression of new cell surface proteins. The markers CD63 and CD203c have been used in recent years to assess basophil activation but there have been many studies that demonstrate that expression of these markers can be dissociated from histamine release. Objective To determine the signal transduction requirements for CD203c and CD63 expression. Methods The current study began by exploring the dependency of CD203c and CD63 expression on protein kinase C (PKC) using known selective inhibitors of PKC. Results Between 30 and 300 nm, Ro-31-8220 and bisindoylmaleimide II (Bis II) had no effect on formyl–met–leu–phe- or anti-IgE-induced CD63 or CD203c but enhanced IgE-mediated expression of CD63 by an average of 15-fold at concentrations >1 μm. These results led to the suggestion that these inhibitors altered the normal pathways of degranulation (by a non-PKC dependent mechanism), shifting the normal presence of piecemeal degranulation to the process termed anaphylactic degranulation (AND). Morphological studies demonstrated that concentrations of Ro-31-8220 and Bis II>1 μm dramatically increased the presence of degranulation sacs, a morphological feature of AND. Conclusion It is proposed that CD63 expression results from only the AND form of histamine release. Cite this as: D. MacGlashan Jr, Clinical & Experimental Allergy, 2010 (40) 1365–1377. [ABSTRACT FROM AUTHOR]

Basophils are the least abundant granulocytes found in the circulation. Until recently, their functions were poorly understood. In the past few years, the list of basophil functions in the context of immunity has dramatically increased. Thus, the need for basophil-deficient animal models to confirm these findings is imperative. In this issue of the JCI, Wada and colleagues introduce the first mouse model in which basophils are conditionally ablated in vivo. Using this model, they then uncover a nonredundant role for basophils in acquired immunity against tick infection. [ABSTRACT FROM AUTHOR]

Abstract: Allergic diseases such as asthma result from inappropriate immunologic responses to common environmental allergens in genetically susceptible individuals. Following allergen exposure, interaction of dendritic cells (DC) with CD4+ T cells leads to the production of Th2 cytokines, which induce B cells to synthesize IgE molecules (sensitization phase). These IgE molecules bind to their high affinity receptors (FcɛRI) on the surface of mast cells and basophils and their subsequent cross-linking by allergen results in the release of preformed and newly synthesized mediators, which cause bronchoconstriction, lung inflammation and airway hyperresponsiveness (AHR) in asthma (effector phase). The complement components C3a and C5a levels are increased in the lungs of patients with asthma and are likely generated via the actions of both allergen and mast cell proteases. In vivo studies with rodents have shown that while C3a facilitates allergen sensitization in some models C5a inhibits this response. Despite this difference, both anaphylatoxins promote lung inflammation and AHR in vivo indicating that cells other than DC and T cells likely mediate the functional effects of C3a and C5a in asthma. This review focuses on the contribution of C3a and C5a in the pathogenesis of asthma with a particular emphasis on mast cells and basophils. It discusses the mechanisms by which anaphylatoxins activate mast cells and basophils and the associated signaling pathways via which their receptors are regulated by priming and desensitization. [Copyright &y& Elsevier]

The role of basophils, the rarest of blood granulocytes, in host immunity has been a mystery. Long considered the poor relative of mast cells, basophils have received much recent attention because of the availability of new reagents and models that reveal unique properties of these cells. Basophils are known to have distinct roles in allergic hypersensitivity reactions and in the immune response to intestinal helminthes. In this review, we highlight these advances and summarize our current understanding of the repertoire of functions attributed to these cells. Despite these recent insights, we are likely only beginning to gain a full understanding of how and where these cells lend effector functions to vertebrate immunity. Advances are likely to come only with the development of specific reagents that enable the finer study of basophil lineage and function. Although many fundamental aspects of basophil biology remain unanswered, the prospects remain bright for unmasking new contributions by these unusual cells. [Copyright &y& Elsevier]

Abstract  The RBL-2H3 cell line is a commonly used histamine-releasing cell line used in inflammation, allergy and immunological research. Quite commonly, it is referred to in research papers as a mast cell line, despite the fact that it is derived from basophils. There is also a lack of consistency, both between different research groups using the same cell line and with both mast cell and basophil physiology. The review follows the development of the RBL-2H3 cell line from its inception and then goes on to assess the nature of the cell line in terms of its characteristics and its response to various stimuli. The relationship of this cell line to the various mast cell subtypes and basophils is discussed and it is concluded that while the RBL-2H3 cell line shares some characteristics with both mast cells and basophils, it is not fully representative of either. [ABSTRACT FROM AUTHOR]

All cellular reactions include feedback loops, both positive and negative. Following all receptor-mediated stimulation there are events that activate the cell response and events that dampen the receptor response back to resting conditions. IgE-mediated activation of mast cells and basophils necessarily includes a variety of signaling events that serve to terminate the activation processes. Some of these negative feedback loops are active even in resting cells and likely serve to establish a set point for the cell’s response to IgE-mediated stimulation. But many negative feedback loops become active only after the cell is stimulated. By and large, it will be these processes that will be discussed in this review. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Context.—The mechanism of fibrosis is not clear in patients with obliterative bronchiolitis after a remote injury. Immune-mediated progression may be a reason. c-KIT (CD117)-positive mast cells have been associated with chronic fibrosing diseases and may potentially be treated with imatinib (Gleevec), a c-KIT blocker. Objective.—To evaluate the role of mast cells in fibrosis associated with obliterative bronchiolitis. Design.—Four cases of obliterative bronchiolitis (household cleaner exposure, ammonia exposure, idiopathic, and posttransplantation) were compared with asthma/emphysema. Small and large airways were stained for CD20, CD3, CD4, CD8, CD117, CD34, CD25, stem cell factor (c-KIT ligand) and with toluidine blue, hematoxylin-eosin, and trichrome. c-KIT (CD117)-stained slides were digitally scanned with Aperio ScanScope and stained cells within the epithelium and subepithelium of small and large airways were counted (per millimeter of basement membrane). Results.—Mast cells were concentrated within the involved subepithelium of small airways in obliterative bronchiolitis (122 cells/mm), unlike asthma/emphysema (25 cells/mm). Conversely, there were more mast cells in the epithelium in cases of asthma/emphysema than in obliterative bronchiolitis (7 cells/mm and 2 cells/mm, respectively). Mast cells were significantly increased around involved airways versus uninvolved airways (52 cells/mm vs 14 cells/mm). Large airways in either group had similar c-KIT (CD117) expression. Stem cell factor was not increased. Conclusions.—Mast cells appear to be concentrated in the lesional small-airway subepithelium in obliterative bronchiolitis. The possible role of c-KIT inhibitors such as imatinib (Gleevec) in the progression of fibrosis preceding the development of obliterative bronchiolitis is discussed. [ABSTRACT FROM AUTHOR]

Prognostic factors in patients with chronic myeloid leukaemia (CML) treated with conventional treatment include age, spleen size, platelet count, blood percentage of blasts, basophils and eosinophils, and cytogenetic abnormalities besides the Philadelphia chromosome. The value of traditional clinical and laboratory features to identify patients at increased risk of imatinib failure has not been established yet. Biological markers such as gene expression profile, v-crk sarcoma virus CT10 oncogene homologue (avian)-like (Crkl) phosphorylation or expression of imatinib transporter proteins have been shown to be useful to predict the response to imatinib. In practice, the response obtained at different time points from the initiation of imatinib is employed to predict the patient''s outcome, with this especially applying to cytogenetic response. The prognostic relevance of early molecular response to imatinib has also been pointed out. Prognostic factors for response to second-generation tyrosine kinase inhibitors (TKI) after imatinib failure are currently being investigated. [Copyright &y& Elsevier]

Background Food allergy is a common allergic disorder – especially in early childhood. The avoidance of the allergenic food is the only available method to prevent further reactions in sensitized patients. A better understanding of the immunologic mechanisms involved in this reaction would help to develop therapeutic approaches applicable to the prevention of food allergy. Objective To establish a multi-cell in vitro model of sensitized intestinal epithelium that mimics the intestinal epithelial barrier to study the capacity of probiotic microorganisms to modulate permeability, translocation and immunoreactivity of ovalbumin (OVA) used as a model antigen. Methods Polarized Caco-2 cell monolayers were conditioned by basolateral basophils and used to examine apical to basolateral transport of OVA by ELISA. Activation of basophils with translocated OVA was measured by β-hexosaminidase release assay. This experimental setting was used to assess how microorganisms added apically affected these parameters. Basolateral secretion of cytokine/chemokines by polarized Caco-2 cell monolayers was analysed by ELISA. Results Basophils loaded with OVA-specific IgE responded to OVA in a dose-dependent manner. OVA transported across polarized Caco-2 cell monolayers was found to trigger basolateral basophil activation. Microorganisms including lactobacilli and Escherichia coli increased transepithelial electrical resistance while promoting OVA passage capable to trigger basophil activation. Non-inflammatory levels of IL-8 and thymic stromal lymphopoietin were produced basolaterally by Caco-2 cells exposed to microorganisms. Conclusion The complex model designed inhere is adequate to learn about the consequence of the interaction between microorganisms and epithelial cells vis-a-vis the barrier function and antigen translocation, two parameters essential to mucosal homeostasis. It can further serve as a direct tool to search for microorganisms with anti-allergic and anti-inflammatory properties. [ABSTRACT FROM AUTHOR]

Detection of allergen-induced basophil activation by flow cytometry has been shown to be a useful tool for allergy diagnosis. The aim of this study was to assess the potential of this technique for the diagnosis of pediatric house dust mite allergy. Quantification of total and specific IgE and basophil activation test were performed to evaluate mite allergic (n = 24), atopic (n = 23), and non-allergic children (n = 9). Allergen-induced basophil activation was detected as a CD63-upregulation. Receiver operating characteristics (ROC) curve analysis was performed to calculate the optimal cut-off value of activated basophils discriminating mite allergic and non-allergic children. ROC curve analysis yielded a threshold value of 18% activated basophils when mite-sensitized and atopic children were studied [area under the curve (AUC) = 0.99, 95% confidence interval (CI) = 0.97–1.01, p < 0.001] with a sensitivity and specificity of 96% for 16 μg/ml mite extract. Analysis of the data obtained with 1.6 μg/ml mite extract defined a cut-off value of 8% activated basophils (AUC = 0.96, 95% CI = 0.91–1.01; p < 0.001) with a sensitivity of 82% and specificity of 100%. Comparison between mite allergic and non-allergic children produced a cut-off of 8% activated basophils (AUC = 1.0) with 16 μg/ml allergen extract and a sensitivity and specificity of 100%. The same threshold and specificity values were obtained with 1.6 μg/ml extract (AUC = 97%, 95% CI = 0.92–1.02; p < 0.001) but sensitivity decreased to 83%. Two atopic children showed negative skin prick and basophil activation tests and high specific IgE (>43 kU/l) values for Dermatophagoides pteronyssinus allergen. They also showed positive prick (wheal diameter >1.0 cm) and basophil activation (>87%) tests and high specific IgE (>100 kU/l) with shrimp allergen. Shrimp sensitization was demonstrated by high levels of Pen a 1-specific IgE (>100 kU/l). Cross-reactivity between mite and shrimp was confirmed by fluorescence enzyme immunoassay (FEIA-CAP) inhibition study in these two cases. This study demonstrated that the analysis of allergen-induced CD63 upregulation by flow cytometry is a reliable tool for diagnosis of mite allergy in pediatric patients, with sensitivity similar to routine diagnostic tests and a higher specificity. Furthermore, this method can provide additional information in case of disagreement between in vivo and in vitro test results. [ABSTRACT FROM AUTHOR]

Important insights have recently been gained in our understanding of how host immune responses mediate resistance to parasitic helminths and control associated pathological responses. Although similar cells and cytokines are evoked in response to infection by helminths as diverse as nematodes and schistosomes, the components of the response that mediate protection are dependent on the particular parasite. In this Review, we examine recent findings regarding the mechanisms of protection in helminth infections that have been elucidated in murine models and discuss the implications of these findings in terms of future therapies. [ABSTRACT FROM AUTHOR]

Abstract: For multicellular organisms, specialization of function has evolved to enable different tissues to carry out specific tasks crucial to the survival of the entire organism. Communication between different cells is vital to coordinate the activity of these separate functions. Individual cells within a tissue must be oriented appropriately to fulfil organ function and structural integrity of the tissue must be maintained. This contribution considers how such group activity is achieved. [Copyright &y& Elsevier]

Background: Functional autoantibodies against the α-chain of the high-affinity IgE receptor (FcϵRIα) 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. [ABSTRACT FROM AUTHOR]

Background Human basophils and mast cells express the low-affinity immunoglobulin (Ig)G receptor FcγRIIB. It has previously been shown in artificial model systems that cross-linking of the high-affinity IgE receptor FcℇRI and FcγRIIB leads to inhibition of FcℇRI signalling. Objective The aim of the present study was to investigate whether cross-linking of FcℇRI and FcγRIIB contributes to IgG-mediated inhibition of histamine release in human basophils in a system using the sera from specific immunotherapy (SIT) patients and the major allergen from birch pollen, Bet v 1. As IgG4 furthermore has been proposed to have special blocking properties, we investigated the significance of IgG subclass specificity for this inhibition. Methods Binding of recombinant Bet v 1–IgG complexes to FcγRII and IgG-binding activities in the sera from 25 birch pollen-allergic patients treated with SIT were measured using 125I-rBet v 1. Inhibition of basophil histamine release was assessed by incubating washed leucocytes with complexes of rBet v 1–IgG with or without blocking of FcγRII. Results We observed low binding of rBet v 1–IgG complexes to FcγRII, which was negatively correlated with the relative IgG4-binding activities. Blocking of FcγRII did not reverse the SIT–IgG-induced inhibition of basophil histamine release. However, IgG-binding activities correlated significantly with the ability of the SIT sera to inhibit basophil histamine release. Conclusion We suggest that at least in birch pollen SIT, the contribution of FcγRIIB-mediated inhibitory signalling to SIT–IgG-induced inhibition of human basophil histamine release is of minor importance. The main contributor to the inhibitory effect of SIT-induced IgG seems to be blocking of the allergen–IgE interaction. [ABSTRACT FROM AUTHOR]

Abstract: The central nucleus of the inferior colliculus is a laminated structure composed of oriented dendrites and similarly oriented afferent fibers that provide a substrate for tonotopic organization. Although inputs from many sources converge in the inferior colliculus, how axons from these sources contribute to the laminar pattern has remained unclear. Here, we investigated the axons from the cochlear nuclei that terminate in the central nucleus of the cat and rat. After characterization of the best frequency of the neurons at the injection sites in the cochlear nucleus, the neurons were labeled with dextran in order to visualize their axons and synaptic boutons in the central nucleus. Quantitative methods were used to determine the size and distribution of the boutons within the laminar organization. Two components in the laminae were identified: (1) a narrow axonal lamina that included the largest fibers and largest boutons; (2) a wide axonal lamina, surrounding the narrow lamina, composed of thin fibers and only small boutons. The wide lamina was approximately 30–40% wider than the narrow lamina, and it often extended more than 100μm beyond the larger boutons on each side. The presence of both thick and thin fibers within the acoustic striae following these injections suggests that large and small fibers/boutons within these bands may originate from different neuronal types in the dorsal and ventral cochlear nucleus. We conclude that the narrow laminae that contain large fibers and boutons originate from larger cell types in the cochlear nucleus. In contrast, the wide lamina composed exclusively of small boutons may represent an input from other, perhaps smaller neurons in the cochlear nucleus. Thus, two types of inferior colliculus laminar structures may originate from the cochlear nucleus, and the small boutons in the wide laminae may contribute a functionally distinct input to the neurons of the inferior colliculus. [Copyright &y& Elsevier]

Most basophilic serine/threonine kinases preferentially phosphorylate substrates with Arg at P-3 but vary greatly in additional strong preference for Arg at P-2 or P-5. The structural basis for P-2 or P-5 preference is known for two AGC kinases (family of protein kinases A, G, and C) in which it is mediated by a single pair of acidic residues (PEN+1 and YEM+1). We sought a general understanding of P-2 and P-5 Arg preference. The strength of Arg preference at each position was assessed in 15 kinases using a new degenerate peptide library approach. Strong P-2 or P-5 Arg preference occurred not only in AGC kinases (7 of 8 studied) but also in calmodulin-dependent protein kinase (CAMK, 1 of 3) and Ste20 (STE) kinases (2 of 4). Analysis of sequence conservation demonstrated almost perfect correlation between (a) strong P-2 or P-5 Arg preference and (b) acidic residues at both PEN+1 and YEM+1. Mutation of two kinases (PKC-θ and p21-activated kinase 1 (PAK1)) confirmed critical roles of both PEN+1 and YEM+1 residues in determining strong R-2 Arg preference. PAK kinases were unique in having exceptionally strong Arg preference at P-2 but lacking strong Arg preference at P-3. Preference for Arg at P-2 was so critical to PAK recognition that PAKI activity was virtually eliminated by mutating the PEN+1 or YEM+1 residues. The fact that this specific pair of acidic residues has been repeatedly and exclusively used by evolution for conferring strong Arg preference at two different substrate positions in three different kinase families implies it is uniquely well suited to mediate sufficiently good substrate binding without unduly restricting product release. [ABSTRACT FROM AUTHOR]

The calcium flux in human basophils was measured by flow cytometry. Peripheral blood mononuclear cells were labeled with anti-CD123 and anti-HLA-DR antibodies, loaded with fluo-3 acetoxymethyl ester (2 μmol/l) in the presence of probenecid (2.5 μmol/l) and Pluronic F-127 (0.02%) for 20 min, and equilibrated with Ca[sup 2+] (1.8 mmol/l) and Mg[sup 2+] (1 mmol/l) for 5 min. The levels of intracellular free calcium were monitored as changes in fluorescence. Cross-linking of surface IgE on basophils with anti-IgE antibodies caused effective calcium flux in atopic, but not in healthy, donors. Concentration-dependent responses to monocyte chemoattractant protein 1 (MCP-1), eotaxin, macrophage inflammatory protein 1 alpha (MIP-1α), and C5a (0.3–10 nmol/l) were observed in all subjects, with a rank order of potency of C5a = MCP-1 > eotaxin > MIP-1α. In contrast, the rank order of potency in causing basophil shape change (i.e., increase in forward scatter) was eotaxin > C5a > MCP-1 > MIP-1α. Nerve growth factor (NGF; 15 nmol/l) did not induce calcium flux in basophils, and pretreatment of cells with a low concentration of NGF (0.3 nmol/l), which has previously been shown to prime basophils for mediator release, had no effect on the calcium response to subsequent stimulation with C5a. We conclude that calcium mobilization is differentially involved in signaling to chemoattractants in basophils and that it is correlated with the agonist’s efficacy to induce mediator release. The data also suggest that priming of basophil responses by NGF does not rely on enhanced calcium mobilization.Copyright © 2003 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Abbreviations. MC: mast cell; T: tryptase; C: chymase; CPA: carboxypeptidase A; Bsp‐1: basophil specific antibody 1. [ABSTRACT FROM AUTHOR]

Mast cells and basophils are central effector cells of allergic reactions and are involved in inflammatory diseases. These cell types produce an array of mediators including a broad spectrum of cytokines. In order to examine whether antiallergic drugs modulate the release of these mediators, we have investigated the influence of dexamethasone and decarboethoxy-loratadine (DEL), the active metabolite of the H[SUB1]-blocking agent loratadine, on the release of IL-6 and IL-8 by the human mast cell line HMC-l and the human basophilic cell line KU812 by ELISA. Dexamethasone (10[SUP-6]-10[SUP-11] M) or Del (10[SUP-5]-10[SUP-14] M) were added to the cells either 1 h prior to or simultaneously with PMA and Ca-ionophore A23l87. When preincubated with the cells, DEL dose-dependently sup- pressed IL-6 release by up to 40% and IL-8 release by up to 5O%. Dexamethasone potently suppressed secretion of both cytokines if simultaneously added to the cells with the stimuli by up to 60% and after preincubation by up to 80%. Since both antihistamines and glucocorticoids are used for treatment of allergic diseases, the findings reported here indicate that these drugs may modulate allergic reactions via inhibition of cytokine release from mast cells and basophils. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editor discusses basophil activation test (BAT) for diagnosing sesame food allergy, adolescents with asthma and expressions of different allergic diseases.

The article discusses the study which examines the influence of basophils in the generation of optimal B-cell memory responses. The study reveals that the capacity of basophils to increase B-cell memory was important in the pathogenic infection when the authors examined the reaction of the immunization of antigen to mice. Furthermore, the used of the in vitro assays showed that the effect of basophils was essential on the cell-cell contact wherein IL-6 was derived.

Background: Flow cytometric basophil activation tests have been developed as cellular tests for in vitro diagnosis of IgE-mediated reactions. Different activation markers (CD63 or CD203c) with distinct ways of regulation have been used after stimulation with various allergens. Objective: It was the aim of the present study to compare basophil activation tests by measuring both CD63 and CD203c upregulation in patients with insect venom allergy. Materials and methods: 43 patients with a history of insect venom anaphylaxis were examined. A careful allergy history was taken, and skin tests and determination of specific IgE-antibodies were performed. Basophil activation tests (BAT) using CD63 or CD203c expression were done after stimulation with different concentrations of bee and wasp venom extracts. 25 healthy subjects with negative history of insect venom allergy were studied as controls. Results: The CD203c protocol showed a slightly higher sensitivity than the CD63 protocol (97% vs. 89%) with regard to patients' history. The magnitude of basophil response was higher with CD203c in comparison to CD63 for both insect venoms. Specificity was 100% for the CD63 protocol and 89% for the CD203c protocol with regard to controls with negative history and negative RAST. Conclusion: These results support the reliability of basophil activation tests using either CD63 or CD203c as cellular tests in the in vitro diagnosis of patients with bee or wasp venom allergy with a slightly higher sensitivity for the CD203c protocol. [ABSTRACT FROM AUTHOR]

The human histamine releasing factor also called tumor protein, translationally controlled causes histamine release from basophils of certain allergic donors. It has identity to the transitionally controlled tumor protein, which was previously designated as p23, and is highly conserved from man to alfalfa plants. While originally described as a growth-related tumor protein, it also has been identified in healthy liver tissue and more recently in macrophages, platelets, kiratonicytes, erythrocytes, hepatocytes as well as tumor cells.

Background: In our previous study about 75% of children with cow''s milk allergy tolerated baked milk products, which improved their prognosis and quality of life. Objective: We sought to identify biomarkers of varying degrees of clinical tolerance among a cohort of children with cow''s milk allergy. Methods: One hundred thirty-two subjects were initially classified as baked milk–reactive, baked milk–tolerant, or having “outgrown milk allergy” based on the results of oral food challenges. The baked milk–tolerant group was then divided into 3 groups based on the amount and degree of heat-denatured milk protein that they could tolerate. Serum was analyzed for allergen-specific IgE and IgG4 levels, basophil reactivity was assessed in whole blood stimulated with serial 10-fold dilutions of milk protein, and skin prick tests (SPTs) were performed to commercial milk extract. Activated basophils were defined by using flow cytometry as CD63brightCD203c+CD123+HLA-DRdim/−CD41a−lineage−. Data were analyzed by using the Jonckheere-Terpstra test. Results: Significant differences across the 5 clinical groups were seen for median casein- and milk-specific IgE levels, casein-specific IgG4 levels, and casein IgE/IgG4 ratios; milk-specific to nonspecific basophil activation ratio, median basophil reactivity, and spontaneous basophil activation (CD203c expression after stimulation with RPMI); and milk SPT wheal diameters. Casein- and milk-specific IgE level, milk-specific basophil reactivity, and milk SPT wheal diameter are all significantly greater among patients with milk allergy who react to baked milk than among those who tolerate it. Conclusions: The majority of patients with milk allergy are able to tolerate some forms of baked milk in their diets. Different phenotypes of children with cow''s milk allergy can be distinguished by casein- and milk-specific IgE levels, milk-specific basophil reactivity, and milk SPT mean wheal diameters. Spontaneous basophil activation is greater among patients with more severe clinical milk reactivity. [Copyright &y& Elsevier]

Background Food allergy is a common and increasing health concern in westernized countries. No effective treatment is available, and accidental ingestion can be life-threatening. Food Allergy Herbal Formula-2 (FAHF-2) blocks peanut-induced anaphylaxis in a murine model of peanut-induced anaphylaxis. It was found to be safe and well tolerated in an acute phase I study of patients with food allergy. Objective We sought to assess the safety of FAHF-2 in an extended phase I clinical trial and determine the potential effects on peripheral blood basophils from patients with food allergy. Methods Patients in an open-label study received 3.3 g (6 tablets) of FAHF-2 three times a day for 6 months. Vital signs, physical examination results, laboratory data, pulmonary function test results, and electrocardiographic data were acquired at baseline and at 2-month intervals. During the course of the study, basophil activation and basophil and eosinophil numbers were evaluated by using CCR3/CD63 staining and flow cytometry. Results Of 18 patients enrolled, 14 completed the study. No significant drug-associated differences in laboratory parameters, pulmonary function study results, or electrocardiographic findings before and after treatment were found. There was a significant reduction ( P < .010) in basophil CD63 expression in response to ex vivo stimulation at month 6. There was also a trend toward a reduction in eosinophil and basophil numbers after treatment. Conclusion FAHF-2 was safe and well tolerated and had an inhibitory effects on basophil numbers in an extended phase I clinical study. A controlled phase II study is warranted. [ABSTRACT FROM AUTHOR]