Granulocytes and mast cells in AllergoOncology-Bridging allergy to cancer: An EAACI position paper.

Derived from the myeloid lineage, granulocytes, including basophils, eosinophils, and neutrophils, along with mast cells, play important, often disparate, roles across the allergic disease spectrum. While these cells and their mediators are commonly associated with allergic inflammation, they also exhibit several functions either promoting or restricting tumor growth. In this Position Paper we discuss common granulocyte and mast cell features relating to immunomodulatory functions in allergy and in cancer. We highlight key mechanisms which may inform cancer treatment and propose pertinent areas for future research. We suggest areas where understanding the communication between granulocytes, mast cells, and the tumor microenvironment, will be crucial for identifying immune mechanisms that may be harnessed to counteract tumor development. For example, a comprehensive understanding of allergic and immune factors driving distinct neutrophil states and those mechanisms that link mast cells with immunotherapy resistance, might enable targeted manipulation of specific subpopulations, leading to precision immunotherapy in cancer. We recommend specific areas of investigation in AllergoOncology and knowledge exchange across disease contexts to uncover pertinent reciprocal functions in allergy and cancer and allow therapeutic manipulation of these powerful cell populations. These will help address the unmet needs in stratifying and managing patients with allergic diseases and cancer.

AllergoOncology: Biomarkers and refined classification for research in the allergy and glioma nexus-A joint EAACI-EANO position paper.

Epidemiological studies have explored the relationship between allergic diseases and cancer risk or prognosis in AllergoOncology. Some studies suggest an inverse association, but uncertainties remain, including in IgE-mediated diseases and glioma. Allergic disease stems from a Th2-biased immune response to allergens in predisposed atopic individuals. Allergic disorders vary in phenotype, genotype and endotype, affecting their pathophysiology. Beyond clinical manifestation and commonly used clinical markers, there is ongoing research to identify novel biomarkers for allergy diagnosis, monitoring, severity assessment and treatment. Gliomas, the most common and diverse brain tumours, have in parallel undergone changes in classification over time, with specific molecular biomarkers defining glioma subtypes. Gliomas exhibit a complex tumour-immune interphase and distinct immune microenvironment features. Immunotherapy and targeted therapy hold promise for primary brain tumour treatment, but require more specific and effective approaches. Animal studies indicate allergic airway inflammation may delay glioma progression. This collaborative European Academy of Allergy and Clinical Immunology (EAACI) and European Association of Neuro-Oncology (EANO) Position Paper summarizes recent advances and emerging biomarkers for refined allergy and adult-type diffuse glioma classification to inform future epidemiological and clinical studies. Future research is needed to enhance our understanding of immune-glioma interactions to ultimately improve patient prognosis and survival.

Occupational physical activity: the good, the bad, and the proinflammatory.

Background: Physical activity (PA) is beneficial for preventing several conditions associated with underlying chronic inflammation, e. g., cardiovascular disease (CVD) and cancer. While an active lifestyle appears to have anti-inflammatory effects, high levels of occupational PA (OPA) were associated with inflammation and elevated mortality risks. We aimed to summarize the current knowledge (1) on the association between inflammation and OPA and (2) its implications for health and mortality. Methods and results: This mini-review summarized relevant literature published before January 2023 using established scientific databases and sources. For the primary outcome, observational studies (S) reporting immunological effects (O) in subjects (P), with high (I) vs. low OPA (C), were included. For secondary outcomes, i.e., morbidity and mortality associated with inflammatory processes, (systematic) reviews were included. While "active" occupations and "moderate" OPA appear to have beneficial effects, low (particularly sedentary) and "high-intensity" OPA (particularly including heavy lifting tasks) were associated with inflammation and (CVD and cancer-related) mortality; higher leisure-time PA has been almost consistently associated with lower proinflammatory markers and all-cause mortality risks. Workplace interventions appear to counter some of the observed health effects of unfavorable work strain. Conclusion: The few studies addressing OPA "intensity" and inflammatory markers are largely heterogeneous regarding OPA classification and confounder control. Sedentary and "heavy" OPA appear to promote proinflammatory effects. In addition to targeted management of work-related physical strain and hazardous environmental co-factors, occupational health providers should focus on employer-initiated exercise interventions and the promotion of leisure-time PA.

Nutritional Provision of Iron Complexes by the Major Allergen Alt a 1 to Human Immune Cells Decreases Its Presentation.

Alternaria alternata is a common fungus strongly related with severe allergic asthma, with 80% of affected individuals being sensitized solely to its major allergen Alt a 1. Here, we assessed the function of Alt a 1 as an innate defense protein binding to micronutrients, such as iron-quercetin complexes (FeQ2), and its impact on antigen presentation in vitro. Binding of Alt a 1 to FeQ2 was determined in docking calculations. Recombinant Alt a 1 was generated, and binding ability, as well as secondary and quaternary structure, assessed by UV-VIS, CD, and DLS spectroscopy. Proteolytic functions were determined by casein and gelatine zymography. Uptake of empty apo- or ligand-filled holoAlt a 1 were assessed in human monocytic THP1 cells under the presence of dynamin and clathrin-inhibitors, activation of the Arylhydrocarbon receptor (AhR) using the human reporter cellline AZ-AHR. Human PBMCs were stimulated and assessed for phenotypic changes in monocytes by flow cytometry. Alt a 1 bound strongly to FeQ2 as a tetramer with calculated Kd values reaching pico-molar levels and surpassing affinities to quercetin alone by a factor of 5000 for the tetramer. apoAlt a 1 but not holoAlta 1 showed low enzymatic activity against casein as a hexamer and gelatin as a trimer. Uptake of apo- and holo-Alt a 1 occurred partly clathrin-dependent, with apoAlt a 1 decreasing labile iron in THP1 cells and holoAlt a 1 facilitating quercetin-dependent AhR activation. In human PBMCs uptake of holoAlt a 1 but not apoAlt a 1 significantly decreased the surface expression of the costimulatory CD86, but also of HLADR, thereby reducing effective antigen presentation. We show here for the first time that the presence of nutritional iron complexes, such as FeQ2, significantly alters the function of Alt a 1 and dampens the human immune response, thereby supporting the notion that Alt a 1 only becomes immunogenic under nutritional deprivation.

Ameliorating Atopy by Compensating Micronutritional Deficiencies in Immune Cells: A Double-Blind Placebo-Controlled Pilot Study.

BACKGROUND: Functional iron deficiency facilitates allergy development and amplifies the symptom burden in people experiencing allergies. Previously we selectively delivered micronutrients to immune cells with ß-lactoglobulin as carrier (holoBLG), resulting in immune resilience and allergy prevention. OBJECTIVE: The clinical efficacy of a food for special medical purposes-lozenge containing ß-lactoglobulin with iron, polyphenols, retinoic acid, and zinc (holoBLG lozenge) was assessed in allergic women. METHODS: In a randomized, double-blind, placebo-controlled pilot study, grass- and/or birch pollen-allergic women (n = 51) were given holoBLG or placebo lozenges over 6 months. Before and after dietary supplementation, participants were nasally challenged and the blood was analyzed for immune and iron parameters. Daily symptoms, medications, pollen concentrations, and well-being were recorded by an electronic health application. RESULTS: Total nasal symptom score after nasal provocations improved by 42% in the holoBLG group versus 13% in the placebo group. The combined symptom medication score during the birch peak and entire season as well as the entire grass pollen season improved in allergic subjects supplemented with the holoBLG lozenge by 45%, 31%, and 40%, respectively, compared with the placebo arm. Participants ingesting the holoBLG lozenge had improved iron status with increased hematocrit values, decreased red cell distribution width, and higher iron levels in circulating CD14+ cells compared with the placebo group. CONCLUSIONS: Targeted micronutrition with the holoBLG lozenge seemed to be effective in elevating the labile iron levels in immune cells and reducing the symptom burden in allergic women in this pilot study. The underlying allergen-independent mechanism provides evidence that dietary nutritional supplementation of the immune system is one of the ways to combat atopy.

AllergoOncology: Danger signals in allergology and oncology: A European Academy of Allergy and Clinical Immunology (EAACI) Position Paper.

The immune system interacts with many nominal 'danger' signals, endogenous danger-associated (DAMP), exogenous pathogen (PAMP) and allergen (AAMP)-associated molecular patterns. The immune context under which these are received can promote or prevent immune activating or inflammatory mechanisms and may orchestrate diverse immune responses in allergy and cancer. Each can act either by favouring a respective pathology or by supporting the immune response to confer protective effects, depending on acuity or chronicity. In this Position Paper under the collective term danger signals or DAMPs, PAMPs and AAMPs, we consider their diverse roles in allergy and cancer and the connection between these in AllergoOncology. We focus on their interactions with different immune cells of the innate and adaptive immune system and how these promote immune responses with juxtaposing clinical outcomes in allergy and cancer. While danger signals present potential targets to overcome inflammatory responses in allergy, these may be reconsidered in relation to a history of allergy, chronic inflammation and autoimmunity linked to the risk of developing cancer, and with regard to clinical responses to anti-cancer immune and targeted therapies. Cross-disciplinary insights in AllergoOncology derived from dissecting clinical phenotypes of common danger signal pathways may improve allergy and cancer clinical outcomes.

Binding to Iron Quercetin Complexes Increases the Antioxidant Capacity of the Major Birch Pollen Allergen Bet v 1 and Reduces Its Allergenicity.

Bet v 1 is the major allergen in birch pollen to which up to 95% of patients sensitized to birch respond. As a member of the pathogenesis-related PR 10 family, its natural function is implicated in plant defense, with a member of the PR10 family being reported to be upregulated under iron deficiency. As such, we assessed the function of Bet v 1 to sequester iron and its immunomodulatory properties on human immune cells. Binding of Bet v 1 to iron quercetin complexes FeQ2 was determined in docking calculations and by spectroscopy. Serum IgE-binding to Bet v 1 with (holoBet v1) and without ligands (apoBet v 1) were assessed by ELISA, blocking experiments and Western Blot. Crosslinking-capacity of apo/holoBet v 1 were assessed on human mast cells and Arylhydrocarbon receptor (AhR) activation with the human reporter cellline AZ-AHR. Human PBMCs were stimulated and assessed for labile iron and phenotypic changes by flow cytometry. Bet v 1 bound to FeQ2 strongly with calculated Kd values of 1 nm surpassing affinities to quercetin alone nearly by a factor of 1000. Binding to FeQ2 masked IgE epitopes and decreased IgE binding up to 80% and impaired degranulation of sensitized human mast cells. Bet v 1 facilitated the shuttling of quercetin, which activated the anti-inflammatory AhR pathway and increased the labile iron pool of human monocytic cells. The increase of labile iron was associated with an anti-inflammatory phenotype in CD14+monocytes and downregulation of HLADR. To summarize, we reveal for the first time that FeQ2 binding reduces the allergenicity of Bet v 1 due to ligand masking, but also actively contributes anti-inflammatory stimuli to human monocytes, thereby fostering tolerance. Nourishing immune cells with complex iron may thus represent a promising antigen-independent immunotherapeutic approach to improve efficacy in allergen immunotherapy.

Proposed Diagnostic Criteria and Classification of Canine Mast Cell Neoplasms: A Consensus Proposal.

Mast cell neoplasms are one of the most frequently diagnosed malignancies in dogs. The clinical picture, course, and prognosis vary substantially among patients, depending on the anatomic site, grade and stage of the disease. The most frequently involved organ is the skin, followed by hematopoietic organs (lymph nodes, spleen, liver, and bone marrow) and mucosal sites of the oral cavity and the gastrointestinal tract. In cutaneous mast cell tumors, several grading and staging systems have been introduced. However, no comprehensive classification and no widely accepted diagnostic criteria have been proposed to date. To address these open issues and points we organized a Working Conference on canine mast cell neoplasms in Vienna in 2019. The outcomes of this meeting are summarized in this article. The proposed classification includes cutaneous mast cell tumors and their sub-variants defined by grading- and staging results, mucosal mast cell tumors, extracutaneous/extramucosal mast cell tumors without skin involvement, and mast cell leukemia (MCL). For each of these entities, diagnostic criteria are proposed. Moreover, we have refined grading and staging criteria for mast cell neoplasms in dogs based on consensus discussion. The criteria and classification proposed in this article should greatly facilitate diagnostic evaluation and prognostication in dogs with mast cell neoplasms and should thereby support management of these patients in daily practice and the conduct of clinical trials.

Morphometric Analysis of Mast Cells in Tumor Predicts Recurrence of Hepatocellular Carcinoma After Liver Transplantation.

Tumor-infiltrating immune cells are relevant prognostic and immunotherapeutic targets in hepatocellular carcinoma (HCC). Mast cells play a key role in allergic response but may also be involved in anticancer immunity. Digital morphometric analysis of patient tissue sections has become increasingly available for clinical routine and provides unbiased quantitative data. Here, we apply morphometric analysis of mast cells to retrospectively evaluate their relevance for HCC recurrence in patients after orthotopic liver transplantation (OLT). A total of 173 patients underwent OLT for HCC at the Medical University of Vienna (21 women, 152 men; 55.2 ± 7.9 years; 74 beyond Milan criteria, 49 beyond up-to-7 criteria for liver transplantation). Tissue arrays from tumors and corresponding surrounding tissues were immunohistochemically stained for mast cell tryptase. Mast cells were quantified by digital tissue morphometric analysis and correlated with HCC recurrence. Mast cells were detected in 93% of HCC tumors and in all available surrounding liver tissues. Tumor tissues revealed lower mast cell density than corresponding surrounding tissues (P < 0.0001). Patients lacking intratumoral mast cells (iMCs) displayed larger tumors and higher tumor recurrence rates both in the whole cohort (hazard ratio [HR], 2.74; 95% confidence interval [CI], 1.09-6.93; P = 0.029) and in patients beyond transplant criteria (Milan HR, 2.81; 95% CI, 1.04-7.62; P = 0.01; up-to-7 HR, 3.58; 95% CI, 1.17-10.92; P = 0.02). Notably, high iMC identified additional patients at low risk classified outside the Milan and up-to-7 criteria, whereas low iMC identified additional patients at high risk classified within the alpha-fetoprotein French and Metroticket criteria. iMCs independently predicted tumor recurrence in a multivariate Cox regression analysis (Milan HR, 2.38; 95% CI, 1.16-4.91; P = 0.019; up-to-7 HR, 2.21; 95% CI, 1.05-4.62; P = 0.035). Conclusion: Hepatic mast cells might be implicated in antitumor immunity in HCC. Morphometric analysis of iMCs refines prognosis of HCC recurrence after liver transplantation.

Gastric Enzyme Supplementation Inhibits Food Allergy in a BALB/c Mouse Model.

Impaired gastric digestion due to suppressed gastric acidity enhances the risk for food allergy development. In the current study, we aimed to evaluate the impact of a supported gastric digestion via application of a pharmaceutical gastric enzyme solution (GES) on food allergy development and allergic reactions in a BALB/c mouse model. The ability of the GES to restore hypoacidic conditions was tested in mice treated with gastric acid suppression medication. To evaluate the impact on allergic symptoms, mice were orally sensitized with ovalbumin (OVA) under gastric acid suppression and subjected to oral challenges with or without GES. The immune response was evaluated by measurement of antibody titers, cytokine levels, mucosal allergy effector cell influx and regulatory T-cell counts. Clinical response was objectified by core body temperature measurements after oral OVA challenge. Supplementation of GES transiently restored physiological pH levels in the stomach after pharmaceutical gastric acid suppression. During oral sensitization, supplementation of gastric enzymes significantly reduced systemic IgE, IgG1 and IgG2a levels and allergic symptoms. In food allergic mice, clinical symptoms were reduced by co-administration of the gastric enzyme solution. Support of gastric digestion efficiently prevents food allergy induction and alleviates clinical symptoms in our food allergy model.

The other side of the coin: IgE deficiency, a susceptibility factor for malignancy occurrence.

Since the discovery of IgE, almost all attention was given to conditions with elevated specific or total IgE levels such as atopy, type I hypersensitivity reactions, or parasitic infestations. Recent prospective and retrospective studies show that having very low IgE levels, such as those seen in IgE deficiency (IgE<2.5 kU/L), is not without clinical consequences. Patients with ultra-low IgE levels have an elevated risk of cancer of any type. These results are in agreement with murine models research which demonstrated that grafted tumors grow faster and bigger on an IgE knockout background. The novel finding that IgE deficiency is a susceptibility factor for cancer, fits very well with the AllergoOncology concept. The reports on a beneficial, cytotoxic function of IgE, in cooperation with its high (FcεRI) and low (FcεRII, CD23) affinity IgE receptors resulting in tumor cell phagocytosis, propose a role of IgE in cancer surveillance. It appears that not only deficiency of serum IgE, but also lack of tissue-bound IgE is important in malignancy susceptibility in these patients. As such, IgE deficient individuals with absent serum and cell-bound IgE as suggested by negative type I hypersensitivity skin tests, are at the highest risk for a malignancy diagnosis. In contrast, IgE deficient individuals with cell-bound IgE depicted through positive type I hypersensitivity skin tests, have lower rates of malignancy diagnosis. The present report discusses the evidence and potential role of ultra-low IgE as a novel biomarker for cancer susceptibility.

IgG4 induces tolerogenic M2-like macrophages and correlates with disease progression in colon cancer.

IgG4 subclass antibodies are expressed in alternative Th2 environments featuring high IL-10 expression, including several solid tumors such as melanoma. To induce tolerance, allergen immunotherapy mediates antibody class switching from pro-inflammatory IgE to anti-inflammatory IgG4. We previously reported that IgG4 drives allergic M2 macrophages toward tolerogenic states. Here we assessed the roles of IgG4 and macrophage activation in colorectal cancer (CRC). In this observer-blinded, case-control study, we analyzed total circulating serum IgE, IgG1 and IgG4 levels in CRC (n = 38) patients with (n = 13, TxNxM1) or without (n = 25, TxNxM0) metastasis, and in healthy donors (n = 21). Primary cultures of circulating monocyte-derived macrophages from healthy controls and CRC patients were further evaluated in their responses to stimulation with IgG1 or IgG4. We found higher absolute serum levels of IgG4 in patients with CRC. IgG4 enabled polarization of macrophages derived from CRC patients and healthy controls into alternatively-activated tolerogenic M2b phenotypes. IgG4-stimulated M2 macrophages were characterized by lower surface CD206, CD163, CD14, and CD11b expression and higher CCL-1, IL-10, and IL-6 production. IgG4 was less potent that IgG1 in triggering antibody-dependent cell-mediated phagocytosis (ADCP) of cancer cells. Further, higher z-normalized IgG4/-IgE sera level ratios correlated with the presence of metastasis (p = .0247 and p = .0009, respectively) in CRC patients. High IgG4 in CRC synergizes with macrophages in shaping an immunosuppressive microenvironment and impairs anti-cancer effector cell functions. The shift of serum IgG4/IgE ratios toward enhanced tolerance induction in metastatic disease indicates a role for high IgG4 in disease progression and poor prognostic outcome.

Cow's milk protein ß-lactoglobulin confers resilience against allergy by targeting complexed iron into immune cells.

BACKGROUND: Beta-lactoglobulin (BLG) is a bovine lipocalin in milk with an innate defense function. The circumstances under which BLG is associated with tolerance of or allergy to milk are not understood. OBJECTIVE: Our aims were to assess the capacity of ligand-free apoBLG versus loaded BLG (holoBLG) to protect mice against allergy by using an iron-quercetin complex as an exemplary ligand and to study the molecular mechanisms of this protection. METHODS: Binding of iron-quercetin to BLG was modeled and confirmed by spectroscopy and docking calculations. Serum IgE binding to apoBLG and holoBLG in children allergic to milk and children tolerant of milk was assessed. Mice were intranasally treated with apoBLG versus holoBLG and analyzed immunologically after systemic challenge. Aryl hydrocarbon receptor (AhR) activation was evaluated with reporter cells and Cyp1A1 expression. Treated human PBMCs and human mast cells were assessed by fluorescence-activated cell sorting and degranulation, respectively. RESULTS: Modeling predicted masking of major IgE and T-cell epitopes of BLG by ligand binding. In line with this modeling, IgE binding in children allergic to milk was reduced toward holoBLG, which also impaired degranulation of mast cells. In mice, only treatments with holoBLG prevented allergic sensitization and anaphylaxis, while sustaining regulatory T cells. BLG facilitated quercetin-dependent AhR activation and, downstream of AhR, lung Cyp1A1 expression. HoloBLG shuttled iron into monocytic cells and impaired their antigen presentation. CONCLUSION: The cargo of holoBLG is decisive in preventing allergy in vivo. BLG without cargo acted as an allergen in vivo and further primed human mast cells for degranulation in an antigen-independent fashion. Our data provide a mechanistic explanation why the same proteins can act either as tolerogens or as allergens.

The Role of IgG4 in the Fine Tuning of Tolerance in IgE-Mediated Allergy and Cancer.

Among the four immunoglobulin G (IgG) subclasses, IgG4 is the least represented in serum of a healthy human and it is considered an "odd" antibody. The IgG4 antibody has unique structural features that affect its biological function. These include the ability to undergo antigen-binding fragment (Fab)-arm exchange, to create fragment crystallizable (Fc) - Fc binding with other IgG4 and other IgG subclass antibodies, have a unique affinity profile for Fc gamma receptors (FcγRs) and no binding to complement component C1q. Altogether, these characteristics support anti-inflammatory roles of IgG4 leading to immune tolerance. Under conditions of chronic antigenic stimulation and Th2-type inflammation, both tissue and serum IgG4 levels are increased. This review seeks to highlight how in allergen immunotherapy IgG4 can confer a protective role as a "blocking" antibody and safeguard from subsequent allergen exposure, while IgG4 can confer immunomodulatory functions to support malignancy. While Th2 conditions drive polarization of macrophages to the M2a subtype, chronic antigen stimulation drives B cell class switching to IgG4 to further support phenotypical macrophage changes towards an M2b-like state. M2b-like macrophages can secrete chemokine (C-C motif) ligand 1 (CCL1) and interleukin-10 (IL-10) to support regulatory cell recruitment and to further shape a tolerogenic microenvironment. Thereby, IgG4 have a Janus-faced role, favorable in allergy but detrimental in cancer.

Harnessing Therapeutic IgE Antibodies to Re-educate Macrophages against Cancer.

Currently, IgG is the only class of antibodies employed for cancer therapy. However, harnessing the unique biological properties of a different class ( e.g., IgE) could engender potent effector cell activation, and unleash previously untapped immune mechanisms against cancer. IgE antibodies are best known for pathogenic roles in allergic diseases and for protective effector functions against parasitic infestation, often mediated by IgE Fc receptor-expressing macrophages. Notably, IgE possess a very high affinity for cognate Fc receptors expressed by tumor-associated macrophages (TAMs). This paper reviews pre-clinical studies, which indicate control of cancer growth by tumor antigen-specific IgE that recruit and re-educate TAMs towards activated profiles. The clinical development harnessing the antitumor potential of recombinant IgE antibodies in cancer patients is also discussed.

Precision medicine in clinical oncology: the journey from IgG antibody to IgE.

PURPOSE OF REVIEW: Cancer is one of the leading causes of death and the incidence rates are constantly rising. The heterogeneity of tumors poses a big challenge for the treatment of the disease and natural antibodies additionally affect disease progression. The introduction of engineered mAbs for anticancer immunotherapies has substantially improved progression-free and overall survival of cancer patients, but little efforts have been made to exploit other antibody isotypes than IgG. RECENT FINDINGS: In order to improve these therapies, 'next-generation antibodies' were engineered to enhance a specific feature of classical antibodies and form a group of highly effective and precise therapy compounds. Advanced antibody approaches include among others antibody-drug conjugates, glyco-engineered and Fc-engineered antibodies, antibody fragments, radioimmunotherapy compounds, bispecific antibodies and alternative (non-IgG) immunoglobulin classes, especially IgE. SUMMARY: The current review describes solutions for the needs of next-generation antibody therapies through different approaches. Careful selection of the best-suited engineering methodology is a key factor in developing personalized, more specific and more efficient mAbs against cancer to improve the outcomes of cancer patients. We highlight here the large evidence of IgE exploiting a highly cytotoxic effector arm as potential next-generation anticancer immunotherapy.

Immune Effects of the Nitrated Food Allergen Beta-Lactoglobulin in an Experimental Food Allergy Model.

Food proteins may get nitrated by various exogenous or endogenous mechanisms. As individuals might get recurrently exposed to nitrated proteins via daily diet, we aimed to investigate the effect of repeatedly ingested nitrated food proteins on the subsequent immune response in non-allergic and allergic mice using the milk allergen beta-lactoglobulin (BLG) as model food protein in a mouse model. Evaluating the presence of nitrated proteins in food, we could detect 3-nitrotyrosine (3-NT) in extracts of different foods and in stomach content extracts of non-allergic mice under physiological conditions. Chemically nitrated BLG (BLGn) exhibited enhanced susceptibility to degradation in simulated gastric fluid experiments compared to untreated BLG (BLGu). Gavage of BLGn to non-allergic animals increased interferon-γ and interleukin-10 release of stimulated spleen cells and led to the formation of BLG-specific serum IgA. Allergic mice receiving three oral gavages of BLGn had higher levels of mouse mast cell protease-1 (mMCP-1) compared to allergic mice receiving BLGu. Regardless of the preceding immune status, non-allergic or allergic, repeatedly ingested nitrated food proteins seem to considerably influence the subsequent immune response.

AllergoOncology: High innate IgE levels are decisive for the survival of cancer-bearing mice.

BACKGROUND: Atopics have a lower risk for malignancies, and IgE targeted to tumors is superior to IgG in fighting cancer. Whether IgE-mediated innate or adaptive immune surveillance can confer protection against tumors remains unclear. OBJECTIVE: We aimed to investigate the effects of active and passive immunotherapy to the tumor-associated antigen HER-2 in three murine models differing in Epsilon-B-cell-receptor expression affecting the levels of expressed IgE. METHODS: We compared the levels of several serum specific anti-HER-2 antibodies (IgE, IgG1, IgG2a, IgG2b, IgA) and the survival rates in low-IgE ΔM1M2 mice lacking the transmembrane/cytoplasmic domain of Epsilon-B-cell-receptors expressing reduced IgE levels, high-IgE KN1 mice expressing chimeric Epsilon-Gamma1-B-cell receptors with 4-6-fold elevated serum IgE levels, and wild type (WT) BALB/c. Prior engrafting mice with D2F2/E2 mammary tumors overexpressing HER-2, mice were vaccinated with HER-2 or vehicle control PBS using the Th2-adjuvant Al(OH)3 (active immunotherapy), or treated with the murine anti-HER-2 IgG1 antibody 4D5 (passive immunotherapy). RESULTS: Overall, among the three strains of mice, HER-2 vaccination induced significantly higher levels of HER-2 specific IgE and IgG1 in high-IgE KN1, while low-IgE ΔM1M2 mice had higher IgG2a levels. HER-2 vaccination and passive immunotherapy prolonged the survival in tumor-grafted WT and low-IgE ΔM1M2 strains compared with treatment controls; active vaccination provided the highest benefit. Notably, untreated high-IgE KN1 mice displayed the longest survival of all strains, which could not be further extended by active or passive immunotherapy. CONCLUSION: Active and passive immunotherapies prolong survival in wild type and low-IgE ΔM1M2 mice engrafted with mammary tumors. High-IgE KN1 mice have an innate survival benefit following tumor challenge.