Exacerbation Of Allergic Responses Research Articles

Elevated Toll-Like Receptor-Induced CXCL8 Secretion in Human Blood Basophils from Allergic Donors Is Independent of Toll-Like Receptor Expression Levels.

Human blood basophils have recently gained interest in addition to their function as allergic effector cells. Previous work suggests the involvement of innate immune mechanisms in the development and exacerbation of allergic responses, which might be mediated by basophils. We assayed the expression levels of Toll-like receptor (TLR) 1, 2, 4 and 6 on purified basophils from birch pollen-, house dust mite-, and non-allergic individuals. Additionally, we compared cytokine and chemokine secretion upon TLR stimulation in these basophil donor groups. Expression of TLR4 on the basophils of the allergic donor groups was decreased and CXCL8 secretion was elevated upon stimulation of TLR1/2 and TLR2/6 compared to the non-allergic donors. Decreased TLR expression and elevated CXCL8 secretion may represent possible mechanisms for aggravation of allergic symptoms in case of parasitic infection.

Genomic Approaches and Oxygen Radical Measurement as Biomarker Candidates of Off-Season Predictor of Pollinosis: A Pilot Study

Background: Particulate pollution is associated with occurrence of asthma and allergy, acting together with allergens in initiating and exacerbating these diseases. Production of reactive oxygen species contributes to this effect of pollutants. We tested the hypothesis that oxygen radicals generated by granulocytes are key regulators in exacerbation of allergic responses by particulate pollution. Methods: Out of pollen season, granulocytes and serum were collected from 17 patients sensitive to pollen allergens and from 13 healthy volunteers. Oxygen radical generation, individual single nucleotide polymorphism types (SOD2, SOD3, GSTP1, CAT, FCER1B and IL4A) , gene expression differences and serum cytokine concentrations were compared with allergen-specific IgE, and histamine-release test results in ability to discriminate between groups. Results: Oxygen radical measurements predicted severity of pollinosis. Allergy (IgE receptor) related genotype FCER1B was associated with increased oxygen radical generation (P=0.04). RNA markers may also predict the onset of hay fever those symptoms getting worse. Interpretation. From our pilot study, genomic approaches and oxygen radical generation by granulocytes in response to pollen particles may be possible molecular markers of allergic inflammation that predicted pollinosis severity. Conclusion: New measurement technique and methodology may elucidate pollinosis patients in their prediction and prevention and may contribute to development of preventive medicine. It is only a pilot study with small sample, but might have possibilities of finding a cut end and a breakthrough in the difficulty of allergic pathophysiology from the viewpoint of genomic approach and radical oxygen measurement. Keywords: A pilot study, IgE relaterd genotyping, OMICS approach, prediction of pollinosis, radical oxygen, RNA profiling.

Helminths: Immunoregulation and Inflammatory Diseases—Which Side AreTrichinellaspp. andToxocaraspp. on?

Macropathogens, such as multicellular helminths, are considered masters of immunoregulation due to their ability to escape host defense and establish chronic infections. Molecular crosstalk between the host and the parasite starts immediately after their encounter, which influences the course and development of both the innate and adaptive arms of the immune response. Helminths can modulate dendritic cells (DCs) function and induce immunosuppression which is mediated by a regulatory network that includes regulatory T (Treg) cells, regulatory B (Breg) cells, and alternatively activated macrophages (AAMs). In this way, helminths suppress and control both parasite-specific and unrelated immunopathology in the host such as Th1-mediated autoimmune and Th2-mediated allergic diseases. However, certain helminths favour the development or exacerbation of allergic responses. In this paper, the cell types that play an essential role in helminth-induced immunoregulation, the consequences for inflammatory diseases, and the contrasting effects of Toxocara and Trichinella infection on allergic manifestations are discussed.

252 The Parasite Echinococcus Granulosus Promotes Allergic Response in Human

BackgroundHelminth parasites are highly antigenic and some types favour the generation or exacerbation of allergic responses by inducing strong Th2-type responses (with the production of cytokines, particularly IL-4). Moreover, recent data suggest that Arginase is involved in the pathogenesis of multiple aspects of allergic disease. In the present work, our aim is to study whether the parasite Echinococcus granulosus induces Th2-type response and whether this is beneficial for the host or not. Echinococcus g. infection, which induces hydatidosis, remains a serious parasitic disease in Algeria. In human, the larval form develops into large cysts especially in the liver and lungs.MethodsWe have investigated the effect of laminated-layer (accelullar layer of hydatic cyst) extract (LLs) on IL-4, and IFN-γ production and Arginase activity in culture performed with mononuclear cells (PBMC). These cells are prepared from peripheral blood of hydatic patients (before and after surgery) and healthy donors. Of note, IFN-γ (Th1 cytokine) downregulates Th2-derived cytokines (like IL-4) which are the best inducer of Arginase pathway. Finally, we have investigated the effects of LLs and IL-4 on protoscoleces (larval form of parasite) viability in PBMC-protoscoleces coculture.ResultsWe have found that LLs enhanced IL-4 production and Arginase activity and reduced IFN-γ production by PBMC. Furthermore, LLs and IL-4 also enhanced parasite survival in PBMC-Parasite cocultures. Moreover, we have purified by chromatography one of the major antigenic protein in LLs: the fraction 4 (F4, 12kDa). This fraction has the same effect as LLs on Th1/Th2 balance. Interestingly, similar findings are observed in cultures and cocultures performed with PBMC of presurgical and postsurgical patient and healthy donors.ConclusionsTaken together, our results suggest that the laminated layer of Echinococcus g. may promote allergic response in humans directly by inducting the Th2 pathway. Moreover, this response allows the parasite survival.

Whole-cell pertussis vaccine protects against Bordetella pertussis exacerbation of allergic asthma

The prevalence of asthma and allergic disease has increased in many countries and there has been speculation that immunization promotes allergic sensitization. Bordetella pertussis infection exacerbates allergic asthmatic responses. We investigated whether whole-cell pertussis vaccine (Pw) enhanced or prevented B. pertussis induced exacerbation of allergic asthma. Groups of mice were immunized with Pw, infected with B. pertussis and/or sensitized to ovalbumin. Immunological, pathological and physiological changes were measured to assess the impact of Pw immunization on immune deviation and airway function. Pw immunization modulated ovalbumin-specific serum IgE production, and reduced local and systemic IL-13 and other cytokine responses to sensitizing allergen. Histopathological examination revealed Pw immunization reduced the severity of airway pathology and decreased bronchial hyperreactivity to methacholine exposure. Pw does not enhance airway IL-13 and consequently does not enhance but protects against the exacerbation of allergic responses. We find no evidence of Pw contributing to allergic asthma, but rather provide evidence of a mechanism whereby whole-cell pertussis vaccination has a protective role.