ABSTRACT
The relationship between the cellular immune response during Trichuris trichiura infection and asthma has not yet been established. In this study, the cytokines interleukin (IL)-2, IL-4, IL-6, IL-10, TNF-α, IFN-γ and IL-17A were evaluated in asthmatic children harboring T.â¯trichiura. For this assessment, asthmatic and non-asthmatic children (ISAAC questionnaire) were submitted to parasitological tests and blood samples were cultured (mitogen stimulation) for cytokine measurements in the supernatant. Asthma frequencies were similar in infected and uninfected children, but IL-4, IL-6, TNF-α and IL-10 levels were high in the infected asthmatic children. Additionally, infected non-asthmatic children exhibited high levels of these cytokines in relation to uninfected non-asthmatic children; however, cytokine levels were lower when compared with infected and asthmatic children. Therefore, T.â¯trichiura infection positively modulated the pro- and anti-inflammatory cytokines in asthmatic children, but a background of asthma seemed to narrow the production of cytokines induced by this helminth.
Subject(s)
Asthma/parasitology , Cytokines/blood , Trichuriasis/immunology , Animals , Asthma/immunology , Brazil , Child , Child, Preschool , Cytokines/immunology , Female , Humans , Hypersensitivity/immunology , Hypersensitivity/parasitology , Immunity, Cellular , Male , TrichurisABSTRACT
Blomia tropicalis mite is highly prevalent in tropical and subtropical regions and it is associated with allergic diseases such as rhinitis and asthma. By using an OVA-model of allergic lung disease, we have previously shown that sensitization in the presence of toll like receptors (TLRs) agonists attenuates subsequent OVA-induced allergic responses. Here, we evaluated the effect of CpG-ODN, a specific synthetic TLR-9 agonist, on the development of experimental asthma induced by Blomia tropicalis extract, a relevant source of aeroallergens. Among different protocols of Blomia tropicalis extract sensitization, the subcutaneous sensitization in the presence of alum adjuvant induced the highest Th2 responses, including high IgE levels. Adsorption of CpG to Blomia tropicalis extract/Alum attenuated the airway hyperreactivity, the infiltration of inflammatory cells including eosinophils, and the IL-5 content in BAL. In addition, lung peribronchial inflammatory infiltrate, mucus production and IL-5-producing CD3+ CD4+ T cells were significantly reduced in the Blomia tropicalis extract/Alum+CpG group. Importantly, CpG inhibited total IgE production as well as active systemic or cutaneous anaphylaxis reactions. Inhibition of pulmonary Th2 responses was associated with increased IL-10 production but not with IFN-γ production. Notably, in IL-10-deficient mice, sensitization with OVA/Alum+CpG resulted in intense lung neutrophilia and IFN-γ production, indicating that IL-10 is necessary to inhibit subsequent Th1 immunity. Our work highlights the mechanisms of allergy attenuation by CpG and it indicates the potential use of Alum-based formulation with CpG to treat allergic processes.
Subject(s)
Adjuvants, Immunologic/therapeutic use , Alum Compounds/chemistry , Asthma/prevention & control , Asthma/parasitology , Pyroglyphidae/physiology , Toll-Like Receptor 9/agonists , Adjuvants, Immunologic/pharmacology , Adsorption , Anaphylaxis/complications , Anaphylaxis/immunology , Anaphylaxis/parasitology , Animals , Asthma/complications , Cytokines/biosynthesis , Disease Models, Animal , Eosinophils/pathology , Female , Hypersensitivity/complications , Hypersensitivity/immunology , Hypersensitivity/parasitology , Immunity/drug effects , Immunization , Interleukin-10/metabolism , Interleukin-4/biosynthesis , Lymph Nodes/drug effects , Lymph Nodes/immunology , Lymph Nodes/pathology , Lymphocyte Subsets/drug effects , Lymphocyte Subsets/immunology , Mice, Inbred C57BL , Neutrophils/pathology , Oligodeoxyribonucleotides/pharmacology , Pyroglyphidae/drug effects , Th1 Cells/drug effects , Th1 Cells/immunology , Th2 Cells/drug effects , Th2 Cells/immunology , Toll-Like Receptor 9/metabolismABSTRACT
BACKGROUND: Asthma is a chronic disease of the airways and its most common phenotype is characterized by a T2 type response with IgE production and inflammatory mediators in response to common allergens. Cysteinyl leukotrienes (CysLTs), LTC4, LTD4 and LTE4, are mediators known to possess important proinflammatory action. CysLTs can bind to the Cysteinyl leukotriene receptor type 2 (CysLTR2) and activate an inflammatory. Polymorphisms in CysLTR2 have been associated with asthma and atopy, although the mechanism is not clear. OBJECTIVE: To evaluate the association between genetic polymorphisms in CYSLTR2 with asthma phenotypes, atopy markers and helminth infection. METHODS: Genotyping was performed using a panel Illumina and carried out in 1245 participants of SCAALA program (Social Change, Asthma, Allergy in Latin American). Logistic regressions for asthma, helminth infections (Trichuris trichiura and Ascaris lumbricoides) and allergy markers (skin tests and IgE production) were performed using PLINK 1.9 software adjusted for sex, age, helminth infection and ancestry markers. RESULTS: The G allele of rs1323556 was negatively associated with asthma in the additive model (OR 0.74, 95% CI 0.59-0.93) and in the dominant model (OR 0.71, 95% CI 0.53-0.74). The G allele of rs1575464 was also negatively associated with asthma in two genetic models, additive (OR 0.77, 95% CI 0.62-0.96) and dominant (OR 0.73, 95% CI 0.55-0.97). The G allele of rs61735175 was positively associated with asthma severity in the additive model (OR 1.72, 95% CI 1.07-2.77) and in the dominant model (OR 1.77, 95% CI 1.09-2.85). Five SNVs were associated with atopy markers and four SNVs were associated with helminth infections. CONCLUSION: Polymorphisms in the CYSLTR2 gene are associated with asthma, atopy markers and helminth infection in Brazilian individuals, which may lead to protection or risk for such conditions, however, more studies are needed to evaluate the functional of this variants here in described.
Subject(s)
Asthma/genetics , Genetic Predisposition to Disease , Hypersensitivity, Immediate/genetics , Receptors, Leukotriene/genetics , Allergens/genetics , Allergens/immunology , Animals , Asthma/epidemiology , Asthma/parasitology , Child , Child, Preschool , Female , Genetic Association Studies , Genotype , Helminthiasis/epidemiology , Helminthiasis/genetics , Helminthiasis/parasitology , Helminths/genetics , Helminths/pathogenicity , Humans , Hypersensitivity , Hypersensitivity, Immediate/parasitology , Inflammation/epidemiology , Inflammation/genetics , Inflammation/parasitology , Male , Phenotype , Polymorphism, Single Nucleotide/geneticsABSTRACT
Asthma is a chronic disease characterized by airway inflammation, obstruction and hyperresponsiveness. Severe asthma affects a small proportion of subjects but results in most of the morbidity, costs and mortality associated with the disease. Studies have suggested that Schistosoma mansoni infection reduces the severity of asthma and prevent atopy. OBJECTIVE: We evaluated the ability of S. mansoni antigens, Sm29 and Sm29TSP-2 to modulate lymphocyte activation status in response to the allergen of the mite Dermatophagoides pteronyssinus (Der p1) in cell cultures of individuals with asthma. METHODS: Thirty four patients were enrolled in this study: seventeen patients with severe asthma (SA group), seventeen patients with mild asthma (MA group) and six controls with no asthma. Peripheral blood mononuclear cells (PBMC) were obtained and stimulated with Sm29 and Sm29TSP-2 in the presence or absence of Der p1. The expression of surface markers and cytokines on lymphocytes was evaluated by flow cytometry and the levels of IL-10 in the culture supernatant were determined by ELISA. RESULTS: The addition of Sm29 and Sm29TSP-2 antigens to PBMC cultures from both groups of subjects with asthma stimulated with Der p1 reduced the frequency of CD4+CD25low cells whereas and increased frequency of CD4+CD25high population was observed compared to unstimulated cultures. Moreover, cultures stimulated with Sm29TSP-2 showed a reduction in the frequency of T cells expressing CD69, IFN-γ, TNF and TGF-ß in the MA group and an increase in the frequency of CD4+TSLPR+ T cells in the SA group. The addition of Sm29 to the cultures reduced the frequency of CD4+CD69+ and CD4+IL-5+ T cells in all asthmatic groups, and reduced the frequency of CD4+ T cells expressing IL-13 in the MA group. The cultures stimulated with Sm29 and Sm29TSP-2 showed an increase in the level of IL-10 in the supernatants. CONCLUSION: These results suggest that the addition of Sm29 and Sm29TSP-2 to the cells cultures from subjects with asthma reduced cell activation markers and altered the cytokine production pattern in a way that can potentialy control the inflammatory response associated with asthma.
Subject(s)
Antigens, Helminth/blood , Asthma/blood , Cytokines/blood , Leukocytes, Mononuclear/parasitology , Schistosoma mansoni/immunology , Adult , Animals , Asthma/parasitology , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/parasitology , Case-Control Studies , Female , Humans , Interleukin-10/blood , Interleukin-13/blood , Interleukin-5/blood , Leukocytes, Mononuclear/immunology , Lymphocyte Activation , Male , Middle Aged , Transforming Growth Factor beta/metabolismABSTRACT
BACKGROUND: Helminths are modulators of the host immune system, and infections with these parasites have been associated with protection against allergies and autoimmune diseases. The human host is often infected with multiple helminth parasites and most studies to date have investigated the effects of helminths in the context of infections with single parasite or types of parasites (e.g. geohelminths). In this study, we investigated how co-infections with three nematodes affect markers of allergic inflammation and asthma in children. We selected Ascaris lumbricoides and Trichuris trichiura, two parasites that inhabit the human intestine and Toxocara spp (Toxocara canis and/or T. cati), intestinal roundworms of dogs and cats that cause systemic larval infection in humans. These parasites were selected as the most prevalent helminth parasites in our study population. RESULTS: 36.4% of children were infected with one parasite; 12.7% with 2 and 5.2% with 3. Eosinophilia>4% and >10% was present in 74.3% and 25.5% of the children, respectively. Total IgE>200 IU/mL, sIgE≥0.70 kU/L and SPT positivity were present in 59.7%, 37.1% and 30% of the children, respectively. 22.7% had recent asthma (12.0% non-atopic and 10.7% atopic). Helminth infections were associated in a dose-dependent way to decrease in the prevalence of SPT and increase in eosinophilia, total IgE, and the production of the regulatory cytokine IL-10 by unstimulated peripheral blood leukocytes. No association with asthma was observed. CONCLUSIONS: Helminth co-infections in this population were associated with increased markers of the Th2 immune response, and with a host immune regulatory phenotype that may suppress allergic effector responses such as immediate hypersensitivity reactions in the skin.
Subject(s)
Asthma/complications , Cities , Coinfection/complications , Cytokines/blood , Dermatitis, Atopic/complications , Helminths/physiology , Poverty , Animals , Asthma/blood , Asthma/parasitology , Biomarkers/metabolism , Child , Child, Preschool , Coinfection/blood , Coinfection/parasitology , Cytokines/biosynthesis , Dermatitis, Atopic/blood , Dermatitis, Atopic/parasitology , Eosinophilia/blood , Eosinophilia/complications , Female , Helminthiasis/blood , Helminthiasis/complications , Humans , Hypersensitivity, Immediate/complications , Hypersensitivity, Immediate/immunology , Immunoglobulin E/blood , Latin America , Leukocytes, Mononuclear/metabolism , Male , Models, Biological , Parasites/physiology , Skin TestsABSTRACT
INTRODUCTION: Association between Ascaris lumbricoides infection and asthma is a controversial subject that has been studied by several authors based on the hygiene theory. This work contributes to better understanding this issue. METHODOLOGY: This was a cross-sectional study involving 1,004 children from a neighborhood of low socioeconomic status in Campina Grande, Paraíba, northeastern Brazil. Asthma was diagnosed using the International Study of Asthma and Allergy in Childhood (ISAAC) questionnaire. Intestinal parasitosis was diagnosed by parasitological examination (the Ritchie technique), and parasite load determined by the Kato-Katz technique. The statistical analysis was descriptive, and hypotheses were tested according to odds ratios. RESULTS: A total of 260 children were infected with A. lumbricoides, and 233 had asthma. Light parasite loads were significantly associated with asthma (wheezing more than three times per year); p = 0.003, OR = 0.41(IC 0.22 - 0.75), while the heavy parasite loads were not; p = 0.002, OR = 2.37(IC 1.35 - 4.18). Similar results were observed in almost all the symptoms of asthma. No association was found with maternal educational level. CONCLUSION: In children living in urban areas of low socioeconomic status, a light parasite load of A. lumbricoides is a protective factor against asthma and its symptoms. Meanwhile, heavy parasite load is a risk factor and contributes to the high prevalence of asthma and its symptoms among these children.
Subject(s)
Ascariasis/etiology , Ascaris lumbricoides/pathogenicity , Asthma/etiology , Asthma/parasitology , Intestinal Diseases, Parasitic/etiology , Parasite Load , Animals , Asthma/epidemiology , Brazil/epidemiology , Child , Child, Preschool , Coinfection , Cross-Sectional Studies , Female , Humans , Intestinal Diseases, Parasitic/parasitology , Male , Parasite Egg Count , Risk Factors , Schistosoma mansoni/isolation & purification , Socioeconomic Factors , Urban PopulationABSTRACT
OBJECTIVE: The aim of this study was to evaluate whether endemic areas for helminth infections in Brazil have lower rates of hospital admission due to asthma and whether reduction in helminth endemicity impacts on asthma morbidity. METHODS: This was a country-wide ecological study in Brazil. Government databases were the source of information. A cross-sectional analysis accessed the risk of a municipality having high rates of hospital admissions due to asthma according to its records of hospital admissions due to Schistossoma mansoni or intestinal helminth infections. A longitudinal analysis accessed the effect of prevention of helminth infection on asthma morbidity. Data were adjusted for the rates of hospital admissions due to influenza, pneumonia, diarrhea, per capita income, Gini index, number of physicians, proportion of literate inhabitants, urbanization and hospital beds. RESULTS: Hospitalization rates due to asthma in the age range of 5-24 years were lower in municipalities endemic for S. mansoni [adjusted OR: 0.992, CI: 0.989-0.994] or for intestinal helminth infections [adjusted OR: 0.994, CI: 0.990-0.997]. Similar results were observed for the age range of 25-64 years. In the longitudinal analysis, municipalities that reduced hospitalizations due to S. mansoni had smaller odds to decrease hospital admissions due to asthma among young populations [adjusted OR: 0.43, CI: 0.22-0.82]. CONCLUSION: We conclude that populations exposed to helminths have lower asthma morbidity. Reduction of helminth infection prevalence in low-income populations was associated with a smaller decline in asthma morbidity.
Subject(s)
Asthma/epidemiology , Helminthiasis/epidemiology , Adult , Animals , Asthma/parasitology , Brazil/epidemiology , Child , Child, Preschool , Cross-Sectional Studies , Helminthiasis/parasitology , Humans , Longitudinal Studies , Middle Aged , Prevalence , Regression Analysis , Socioeconomic Factors , Young AdultABSTRACT
Nematode infections such as Ascariasis are important health problems in underdeveloped countries, most of them located in the tropics where environmental conditions also promote the perennial co-exposure to high concentrations of domestic mite allergens. Allergic diseases are common, and most of patients with asthma exhibit a predominant and strong IgE sensitization to mites. It is unknown whether co-exposure to Ascaris lumbricoides and the domestic mites Blomia tropicalis and Dermatophagoides pteronyssinus potentiates Th2 responses and IgE sensitization, thereby modifying the natural history of allergy. Recently, we obtained experimental evidence of a high cross-reactivity between the allergenic extracts of these invertebrates, involving well-known allergens such as tropomyosin and glutathione transferases. There is indirect evidence suggesting that the clinical impact of these findings may be important. In this review, we discuss the potential role of this cross-reactivity on several aspects of allergy in the tropics that have been a focus of a number of investigations, some of them with controversial results.
Subject(s)
Ascaris lumbricoides/immunology , Cross Reactions , Hypersensitivity/immunology , Immunoglobulin E/immunology , Mites/immunology , Animals , Ascariasis/complications , Ascariasis/immunology , Asthma/immunology , Asthma/parasitology , Humans , Mite Infestations/complications , Mite Infestations/immunologySubject(s)
Air Pollution, Indoor/prevention & control , Allergens/analysis , Asthma/prevention & control , Dermatophagoides farinae/immunology , Dermatophagoides pteronyssinus/immunology , Skin Tests/statistics & numerical data , Students/statistics & numerical data , Adolescent , Algorithms , Altitude , Animals , Asthma/parasitology , Child , Dust/analysis , Ecuador/epidemiology , Female , Humans , Male , Respiratory Hypersensitivity/prevention & control , Schools/standards , Young AdultABSTRACT
In order to evaluate the association between the infection by Toxocara canis and the symptoms of asthma in children from a subtropical region with high prevalence of toxocariasis, 47 asthmatic children and 53 non-asthmatics as a control group were studied. A complete physical examination was performed and clinical and epidemiological data were registered. In asthmatic children the frequency and severity of symptoms were classified in grades I to IV. The presence of anti-Toxocara canis antibodies in both groups was evaluated employing a solid phase ELISA method with excretion/secretion antigens, and total Ig E was also measured. Results showed a total seropositivity of 55%, 57.4% in children with asthma and 52.8% in the control group. Among asthmatics with severe symptoms (grade II, III and IV), there was a 67.7% of seropositivity while in children with symptoms of grade I there was a 37.5% (p = 0.0470). The infection with T. canis could act as a co-factor increasing the severity of the symptoms of bronchial asthma.
Subject(s)
Antibodies, Helminth/blood , Antigens, Helminth/immunology , Asthma/parasitology , Toxocara canis/immunology , Toxocariasis/epidemiology , Animals , Argentina/epidemiology , Asthma/diagnosis , Asthma/immunology , Case-Control Studies , Child , Enzyme-Linked Immunosorbent Assay , Female , Humans , Male , Prevalence , Severity of Illness Index , Toxocariasis/complications , Toxocariasis/immunologyABSTRACT
A fin de evaluar la relación entre la infección por Toxocara canis y los síntomas del asma bronquial en niños de una región subtropical con alta prevalencia de toxocariosis, se estudiaron 47 niños con asma y 53 sin asma como grupo control. Se efectuó el examen físico completo, registrándose datos clínicos y epidemiológicos. En los niños con asma se categorizó el patrón de presentación, frecuencia y gravedad de los síntomas con una escala de I a IV. Se investigó la presencia de anticuerpos anti-Toxocara canis en ambos grupos mediante el método de ELISA en fase sólida, empleando antígeno de excreción/secreción y se efectuó dosaje de Ig E total. Los resultados muestran una seropositividad del 55% en el total de los niños, del 57.4% en los niños con asma y del 52.8% en los controles. En los niños con sintomatología más grave (grado II, III y IV) hubo un 67.7% de seropositivos, mientras que en los niños con síntomas de grado I la seropositividad fue de 37.5% (p = 0.0470). La infección por T. canis actuaría como un co-factor agravante de los síntomas del asma bronquial.
In order to evaluate the association between the infection by Toxocara canis and the symptoms of asthma in children from a subtropical region with high prevalence of toxocariasis, 47 asthmatic children and 53 non-asthmatics as a control group were studied. A complete physical examination was performed and clinical and epidemiological data were registered. In asthmatic children the frequency and severity of symptoms were classified in grades I to IV. The presence of anti-Toxocara canis antibodies in both groups was evaluated employing a solid phase ELISA method with excretion/secretion antigens, and total Ig E was also measured. Results showed a total seropositivity of 55%, 57.4% in children with asthma and 52.8% in the control group. Among asthmatics with severe symptoms (grade II, III and IV), there was a 67.7% of seropositivity while in children with symptoms of grade I there was a 37.5% (p = 0.0470). The infection with T. canis could act as a co-factor increasing the severity of the symptoms of bronchial asthma.
Subject(s)
Animals , Child , Female , Humans , Male , Antibodies, Helminth/blood , Antigens, Helminth/immunology , Asthma/parasitology , Toxocara canis/immunology , Toxocariasis/epidemiology , Argentina/epidemiology , Asthma/diagnosis , Asthma/immunology , Case-Control Studies , Enzyme-Linked Immunosorbent Assay , Prevalence , Severity of Illness Index , Toxocariasis/complications , Toxocariasis/immunologyABSTRACT
There is limited data on the human mucosal immune response to geohelminths, but extensive data from experimental animals. Geohelminth infections may modulate mucosal immunity with effects on parasite expulsion or persistence and mucosal inflammation. Geohelminths are considered to have important effects on immunity to mucosal vaccines, infectious disease susceptibility, and anti-inflammatory effects in inflammatory bowel disease and asthma. This review will discuss the findings of studies of human immunity to geohelminths and their potential effects on non-parasite mucosal immune responses. Such effects are likely to be of public health importance in middle- and low-income countries where these parasites are endemic. There is a need for human studies on the effects of geohelminth infections on mucosal immunity and the potential for anthelmintic treatment to modify these effects. Such studies are likely to provide important insights into the regulation of mucosal immunity and inflammation, and the development of more effective mucosal vaccines.
Subject(s)
Helminthiasis/immunology , Immunity, Mucosal , Intestinal Diseases, Parasitic/immunology , Animals , Asthma/immunology , Asthma/parasitology , Helminthiasis/complications , Helminthiasis/prevention & control , Humans , Inflammatory Bowel Diseases/immunology , Inflammatory Bowel Diseases/parasitology , Intestinal Diseases, Parasitic/complications , Intestinal Diseases, Parasitic/prevention & control , Vaccines/administration & dosage , Vaccines/immunologyABSTRACT
La reactividad alérgica frente a Anisakis simplex se ha convertido en un problema de salud pública en muchos países del mundo. En Venezuela, se ha reportado la presencia de mamíferos marinos infectados y se ha evidenciado la presencia del parásito en pescados de consumo masivo procedentes de las zonas costeras de oriente y occidente del país. No obstante, la importancia de este helminto en el desarrollo y severidad de patologías alérgicas no ha sido evaluada en el país. El objetivo de este estudio fue evaluar la reactividad alérgica al An. simplex en un grupo de 144 niños del estado de Nueva Esparta, así como su posible relación con la severidad de asma bronquial y rinitis alérgica. Todos los niños fueron evaluados utilizando un cuestionario socioeconómico validado y modificado de Graffar y un cuestionario validado según los criterios de ARIA (International Consensus Report) para rinitis alérgica, GINA (WHO/NIH Global Initiative for Asthma) para asma bronquial y Hannifin para dermatitis atópica, respectivamente. Se realizaron encuestas para evaluar las principales fuentes de alergenos a los cuales se expone la población de estudio. Se realizó la evaluación física de los niños y se practicaron pruebas cutáneas, así como pruebas de funcionalismo pulmonar. Encontramos un alto porcentaje (45%) de niños con pruebas de piel positiva al An. simplex. Se observó una mayor prevalencia y severidad, de asma y rinitis en aquellos niños con pruebas de piel positivas a An. simplex. Dado que ha sido previamente reportada la reactividad cruzada entre Ascaris lumbricoides y An. simplex, es importante considerar que la alta reactividad encontrada frente al An. simplex pueda deberse a la co-infección por Ascaris. De igual forma, la sensibilización frente a An. simplex, ya sea especifica o por reactividad cruzada existe, lo que sugiere que las autoridades locales deben considerar ciertas medidas preventivas, para evitar el consumo de pescados crudos o posiblemente parasitados con este helminto, que podrían exacerbar la patología respiratoria.
Allergic reactivity to Anisakis simplex has become in a health problem in many parts of the World. In Venezuelan coasts, it has been found infecting marine mammals and also different parasites fishes commonly consumed by human. However, the association of this helminth with the development and severity of allergic reactivity has not been previously evaluated in Venezuela. The aim of this study was to evaluate the allergic reactivity to An. simplex in a group 144 children from Nueva Esparta, state, and its possible relation with bronquial asthma and rhinitis allergic severity. All children were evaluated using a validated socioeconomic questionnaire modified by Graffar, and a validate questionnaire according to ARIA (International Consensus Report) for allergic rhinitis, GINA (WHO/NIH Global Initiative for Asthma) for bronquial asthma and Hannifin for atopic dermatitis. Surveys were performed in order to evaluate the main sources of allergens to which the study population exposes itself. Children physical evaluation and skin prick test were performed, as well as pulmonary function test. We found a high percentage (45%) of children with positive skin prick test to An. simplex. Moreover, a greatest prevalence and severity of asthma and rhinitis, was observed in those children with positive skin prick test to An. simplex. Since it has been reported the presence of the crossed reactivity between Ascaris lumbricoides and An. simplex, its important to consider that the high reactivity found to An. simplex might be due to the Co-infection with A. lumbricoides. Nevertheless, the sensibilization to An. simplex, due by specific or by crossed reactivity exists, and it should be considered by local health authorities in order to prevent the exacerbation of the respiratory pathologies mediated by the consumption of fresh fishes potentially infected.
Subject(s)
Humans , Male , Adolescent , Female , Child, Preschool , Child , Allergy and Immunology/statistics & numerical data , Asthma/immunology , Asthma/microbiology , Asthma/parasitology , Anisakis/immunology , Anisakis/parasitologyABSTRACT
Non-atopic asthma is the predominant phenotype in non-affluent parts of Latin America. We recently reported that infestation with Ascaris lumbricoides increased the risk of non-atopic asthma in less affluent areas of Brazil but the mechanism is unclear. The present study was conducted to determine whether helminth infestation is associated with heightened bronchial responsiveness (BHR), a common finding in asthma. A random sample of 50 asthmatic and 50 non-asthmatic controls (mean age 10.1 years) were selected from a larger cohort (n = 1,011) without knowledge of their helminth infestation status. Three stool samples were collected from each child on different days and each sample was analyzed by the Kato-Katz method for quantitative determination of helminth eggs. Bronchial provocation tests were performed with inhaled 4.5% hypertonic saline using the ISAAC Phase II standardized protocol. There was no difference between the prevalence of positive BHR in the asthmatics (20.4%) compared with the controls (14.6%) (P = 1.0). Helminth infestation was detected in 24.0% of children, with A. lumbricoides being the most common. Children with high load infestation (>or=100 eggs/g) were five times more likely to have BHR than children with low load or no infestation. Despite the small sample size the results of the present study suggest that the link between high load helminth infestation and non-atopic asthma may be mediated via heightened bronchial responsiveness, possibly due to an inflammatory response to the pulmonary phase of the helminth life cycle.
Subject(s)
Ascariasis/complications , Ascaris lumbricoides/immunology , Asthma/parasitology , Bronchial Hyperreactivity/parasitology , Animals , Ascariasis/immunology , Ascaris lumbricoides/isolation & purification , Asthma/immunology , Brazil , Bronchial Hyperreactivity/immunology , Bronchial Provocation Tests , Child , Female , Humans , MaleABSTRACT
To describe the principal evidence in the literature regarding the interrelationship among helminth infections, atopy, and asthma, a nonsystematic review of the literature was conducted. Among the publications on the subject, we found a number in which there was controversy regarding the capacity of geohelminth infections to inhibit responsiveness to skin allergy tests and to minimize the symptoms of allergic diseases. However, although small in number, studies of patients infected with Schistosoma spp. suggest that these helminths can inhibit the responsiveness to skin allergy testing and minimize asthma symptoms. Evidence provided by in vitro studies suggests that helminthiases inhibit T helper 1- and T helper 2-type immune responses. This opens new therapeutic possibilities for the treatment of immune system diseases.
Subject(s)
Asthma/immunology , Helminthiasis/immunology , Hypersensitivity, Immediate/immunology , Animals , Asthma/parasitology , Humans , Interleukin-10/immunology , Schistosomiasis/immunology , Skin Tests , Th1 Cells/immunology , Th2 Cells/immunologyABSTRACT
Este estudo teve como objetivo descrever as principais evidências encontradas na literatura acerca da inter-relação entre infecções helmínticas, atopia e asma. Foi feita uma revisão não sistemática da literatura. Encontramos numerosas publicações sobre o tema nas quais se verifica controvérsia quanto à capacidade das infecções por geohelmintos de inibir a reatividade ao teste alérgico cutâneo e os sintomas das doenças alérgicas. Por outro lado, estudos em pacientes infectados por Schistosoma spp., apesar de escassos, sugerem que estes helmintos são capazes de inibir a reatividade ao teste alérgico cutâneo e os sintomas de asma. Nos estudos in vitro, as evidências sugerem que as helmintíases inibem as respostas imunes mediadas por linfócitos T auxiliares do tipo 1 e 2, o que abre novas possibilidades terapêuticas para o tratamento de doenças do sistema imunológico.
To describe the principal evidence in the literature regarding the interrelationship among helminth infections, atopy, and asthma, a nonsystematic review of the literature was conducted. Among the publications on the subject, we found a number in which there was controversy regarding the capacity of geohelminth infections to inhibit responsiveness to skin allergy tests and to minimize the symptoms of allergic diseases. However, although small in number, studies of patients infected with Schistosoma spp. suggest that these helminths can inhibit the responsiveness to skin allergy testing and minimize asthma symptoms. Evidence provided by in vitro studies suggests that helminthiases inhibit T helper 1- and T helper 2-type immune responses. This opens new therapeutic possibilities for the treatment of immune system diseases.
Subject(s)
Animals , Humans , Asthma/immunology , Helminthiasis/immunology , Hypersensitivity, Immediate/immunology , Asthma/parasitology , /immunology , Skin Tests , Schistosomiasis/immunology , Th1 Cells/immunology , /immunologyABSTRACT
We investigated the prevalence and risk factors for wheezing and asthma in young Amazonian children. A population-based cross-sectional survey of 606 children aged 6-59 months was performed in two small towns in Acre State, Northwestern Brazil. Information on outcome variables (recent wheezing and medical diagnosis of asthma) and demographic, socioeconomic, environmental, maternal and nutritional variables was obtained by interviewing children's mothers or guardians. Infections with intestinal parasites and antibodies to the zoonotic nematode Toxocara were diagnosed using standard laboratory techniques. Multiple unconditional logistic regression models were used to describe associations between independent variables and outcomes. The prevalence of recent wheezing (one or more reported episodes in the past 12 months) was 42.6%, but only 19.8% of wheezing children were also reported to have a medical diagnosis of asthma (prevalence, 8.5%); 21.5% of the children examined had antibodies to Toxocara. Increased risk of asthma was independently associated with early introduction of bottle feeding, defined as <4 months of exclusive breastfeeding [adjusted odds ratio (aOR) = 2.21, 95% confidence interval (95% CI), 1.07-4.59, P = 0.033], and seropositivity to Toxocara (aOR = 2.37, 95% CI 1.17-4.77, P = 0.016), suggesting two potential targets for public health interventions.
Subject(s)
Asthma/etiology , Bottle Feeding/adverse effects , Respiratory Sounds , Toxocara/isolation & purification , Animals , Asthma/parasitology , Brazil/epidemiology , Child, Preschool , Cross-Sectional Studies , Female , Humans , Infant , Male , Prevalence , Risk Factors , Surveys and Questionnaires , Toxocara/pathogenicityABSTRACT
Asthmatics infected with Schistosoma mansoni have a less severe course of asthma and an inhibition of the Th2 inflammatory response that seems to be mediated by interleukin (IL-10). The objective of this study was to evaluate the capacity of some S. mansoni antigens to stimulate IL-10 production in vitro by cells of asthmatic infected individuals. Peripheral bloods mononuclear cells were stimulated with the S. mansoni recombinant antigens Sm22.6, Sm14, P24, and PIII antigen. IL-10 was measured in the supernatants of cultures. As the recombinant antigens were cloned in Escherichia coli, we blocked contaminant endotoxin with polymyxin B added to the cultures. We demonstrated that all antigens used drove high production of IL-10 in S. mansoni infected individuals (n = 13, 408 ± 514 and 401 ± 383 pg/ml, 484 ± 245 pg/ml, 579 ± 468 pg/ml, respectively). In asthmatics infected with S. mansoni (n = 21) rP24 induced higher levels of IL-10 (565 ± 377 pg/ml) when compared to PIII, rSm14 and rSm22.6 (184 ± 209 pg/ml; 292 ± 243 pg/ml; 156 ± 247 pg/ml, respectively). Conclusion: the S. mansoni antigens evaluated in this study stimulated IL-10 production by cells from infected individuals and therefore they have the potential to be used as a modulator of the inflammatory response in asthma.
Subject(s)
Adolescent , Adult , Animals , Child , Female , Humans , Male , Antigens, Helminth/immunology , Asthma/immunology , /biosynthesis , Recombinant Proteins/immunology , Schistosomiasis mansoni/immunology , Asthma/complications , Asthma/parasitology , Cells, Cultured , Leukocytes, Mononuclear/immunology , Leukocytes, Mononuclear/parasitology , Polymyxin B/pharmacology , Schistosomiasis mansoni/complicationsABSTRACT
OBJETIVO: Eosinofilia e elevação de IgE sérica são expressões de atopia, contudo há fatores intervenientes como, por exemplo, as parasitoses intestinais. Esta pesquisa verifica a relação entre IgE sérica total, eosinófilos e IgE específica anti-áscaris em indivíduos portadores de asma e/ou rinite alérgica. MÉTODOS: Estudo do tipo transversal em adolescentes portadores de asma e/ou rinite alérgica que foram examinados quanto ao nível sérico de IgE total, de IgE anti-áscaris e de contagem dos eosinófilos sangüíneos. RESULTADOS: Foram analisados 101 pacientes com idade entre 12 e 21 anos. A mediana da IgE foi 660 UI/mL (P25-75 243,5-1500), e a dos eosinófilos foi 510 células/mm³ (P25-75 284-811). A IgE anti-áscaris foi positiva em 73 por cento (74/101) da amostra, mas houve apenas 33,7 por cento (34/101) de positividade ao parasitológico de fezes. Os coeficientes de correlação encontrados foram: 0,34 (p = 0,001) entre IgE total e eosinófilos, 0,52 (p < 0,001) entre IgE total e IgE anti-áscaris e 0,26 (p = 0,01) entre eosinófilos e IgE anti-áscaris. O modelo de regressão linear múltipla final encontrou que IgE anti-áscaris foi fator contribuinte para IgE sérica total com coeficiente de determinação (r2 ajustado) de 0,25 (F = 12,35; p < 0,001), e esse efeito foi independente de contagem de eosinófilos séricos e de parasitose intestinal por helmintos. CONCLUSÃO: Em pacientes com alergia respiratória e IgE sérica total bastante elevada, oriundos de áreas com alto risco de infecção por helmintos, a pesquisa de IgE anti-áscaris como possível fator explicativo pode ser de maior ajuda que a realização do parasitológico de fezes.
OBJECTIVE: Eosinophilia and increased serum IgE levels are indicators of atopy; however, other factors can also play a key role, such as intestinal parasitic infections. This study assesses the relationship between total serum IgE, eosinophil count, and anti-Ascaris IgE in individuals with asthma and/or allergic rhinitis. METHODS: A cross-sectional study was carried out in adolescents with asthma and/or allergic rhinitis. The patients had their total serum IgE, anti-Ascaris IgE and eosinophil count measured. RESULTS: A total of 101 patients aged 12 to 21 years were assessed. Median IgE level was 660 IU/mL (P25-75 243.5-1500), and the eosinophil count corresponded to 510 cells/mm³ (P25-75 284-811). Anti-Ascaris IgE was positive in 73 percent (74/101) of the individuals, but parasitological stool examination yielded positive results in only 33.7 percent (34/101). The correlation coefficients were the following: 0.34 (p = 0.001) between total IgE level and eosinophil count, 0.52 (p < 0.001) between total IgE level and anti-Ascaris IgE, and 0.26 (p = 0.01) between eosinophil count and anti-Ascaris IgE. The final multiple linear regression model pointed out that anti-Ascaris IgE contributed to a total serum IgE level with a coefficient of determination (adjusted R²) of 0.25 (F = 12.35; p < 0.001). This effect occurred regardless of eosinophil count and of the presence of intestinal helminthic infection. CONCLUSION: In patients with respiratory allergy and increased total serum IgE levels living in areas where there is a high risk for helminthic infections, the quantification of anti-Ascaris IgE can be more useful and more insightful than the parasitological stool examination.
Subject(s)
Adolescent , Adult , Animals , Child , Female , Humans , Male , Ascaris lumbricoides/immunology , Asthma/blood , Eosinophils , Immunoglobulin E/blood , Rhinitis/blood , Asthma/parasitology , Biomarkers , Chronic Disease , Confidence Intervals , Cross-Sectional Studies , Helminthiasis/blood , Helminthiasis/immunology , Intestinal Diseases, Parasitic/blood , Intestinal Diseases, Parasitic/immunology , Leukocyte Count , Linear Models , Rhinitis/parasitologyABSTRACT
OBJECTIVE: Eosinophilia and increased serum IgE levels are indicators of atopy; however, other factors can also play a key role, such as intestinal parasitic infections. This study assesses the relationship between total serum IgE, eosinophil count, and anti-Ascaris IgE in individuals with asthma and/or allergic rhinitis. METHODS: A cross-sectional study was carried out in adolescents with asthma and/or allergic rhinitis. The patients had their total serum IgE, anti-Ascaris IgE and eosinophil count measured. RESULTS: A total of 101 patients aged 12 to 21 years were assessed. Median IgE level was 660 IU/mL (P(25-75) 243.5-1500), and the eosinophil count corresponded to 510 cells/mm(3) (P(25-75) 284-811). Anti-Ascaris IgE was positive in 73% (74/101) of the individuals, but parasitological stool examination yielded positive results in only 33.7% (34/101). The correlation coefficients were the following: 0.34 (p = 0.001) between total IgE level and eosinophil count, 0.52 (p < 0.001) between total IgE level and anti-Ascaris IgE, and 0.26 (p = 0.01) between eosinophil count and anti-Ascaris IgE. The final multiple linear regression model pointed out that anti-Ascaris IgE contributed to a total serum IgE level with a coefficient of determination (adjusted R(2)) of 0.25 (F = 12.35; p < 0.001). This effect occurred regardless of eosinophil count and of the presence of intestinal helminthic infection. CONCLUSION: In patients with respiratory allergy and increased total serum IgE levels living in areas where there is a high risk for helminthic infections, the quantification of anti-Ascaris IgE can be more useful and more insightful than the parasitological stool examination.