Severity of atopic dermatitis and Ascaris lumbricoides infection: an evaluation of CCR4+ and CXCR3+ helper T cell frequency / Gravidade da dermatite atópica e infecção por Ascaris lumbricoides: uma avaliação da frequência de células T auxiliares CCR4+ e CXCR3+

INTRODUCTION: Ascaris lumbricoides-infected patients present lower prevalence of severe atopic dermatitis. METHODS: Peripheral blood of infected children with atopic dermatitis was assessed by flow cytometry of the frequency of Th1 and Th2 cells through the expression of CXCR3 and CCR4 chemokine receptors, respectively. RESULTS: Helminth-free patients with atopic dermatitis presented a high frequency of CCR4+Th2 cells. Parasitized patients with atopic dermatitis showed a lower frequency of CXCR3+Th1 cells compared to infected individuals only. CONCLUSIONS: Ascariasis modifies the blood traffic of Th2 cells in atopic dermatitis patients, while the allergic disease down-regulates the traffic of Th1 cells in parasitized patients.

INTRODUÇÃO: Pacientes infectados com Ascaris lumbricoides apresentam menor prevalência de dermatite atópica grave. MÉTODOS: Sangue periférico de crianças infectadas com dermatite atópica foi analisado por citometria de fluxo quanto à frequência de células Th1 e Th2 pela expressão de receptores de quimiocina CXCR3 e CCR4, respectivamente. RESULTADOS: Pacientes sem helmintos com dermatite atópica apresentaram alta frequência de células Th2CCR4+. Pacientes parasitados com dermatite atópica apresentaram menor frequência de células Th1CXCR3+ comparados aos indivíduos apenas infectados. CONCLUSÕES: Ascaridiases altera o tráfego sanguíneo de células Th2 em pacientes com dermatite atópica, enquanto a doença alérgica diminui o tráfego de células Th1 em pacientes parasitados.

Exposición del antígeno T eritrocitario por acción de Ascaris lumbricoides / Exposure of erythrocyte T antigen by Ascaris lumbricoides action / Exposição do antígeno T eritrocitário por ação de Ascaris lumbricoides

La poliaglutinabilidad de los glóbulos rojos puede deberse al desenmascaramiento del antígeno T críptico debido a la acción de neuraminidasas microbianas que eliminan residuos terminales de ácido siálico en la membrana del hematíe. En experiencias preliminares se demostró que Ascaris lumbricoides capta ácido siálico del eritrocito y que las suspensiones globulares en medio enzimático, incubadas con este parásito, pierden totalmente la capacidad de agregación. El objetivo fue estudiar la exposición del antígeno T eritrocitario, por acción de A. lumbricoides sobre la carga aniónica de glóbulos rojos deficientes en ácido siálico. Se trabajó con 48 extractos de ejemplares adultos del parásito ([EA]) y un concentrado de larvas L1/ L2 ([CLAL]):1300-1500 larvas/mL). Se utilizaron eritrocitos Grupo O en medio enzimático de bromelina (GRB) y eritrocitos Control en medio salino (GRC). El sedimento globular de GRB se incubó con igual volumen de [EA]/ [CLAL] y el de GRC con solución fisiológica durante 120 minutos a 37 ºC. Se realizaron Pruebas de Aglutinación en Placa y en Tubo, enfrentando los GRB y GRC a sueros humanos de adulto y de cordón. Los resultados mostraron que el 33,33% de los GRB incubados con [EA] y el 66,67% de los GRB incubados con [CLAL] aglutinaron con suero de adulto, pero no con suero de cordón. Los GRC no aglutinaron con ninguno de los sueros. Es la primera vez que se comunica la exposición del antígeno T eritrocitario por acción de un parásito. La activación T podría producir autoaglutinación y hemólisis en el hombre adulto y representaría un factor de riesgo transfusional en la población infantil.

Red cell polyagglutination may be due to the unmasking of the cryptic T antigen by the action of microbial neuraminidases, which remove terminal sialic acid residues in the erythrocyte membrane. Previous experiences showed that Ascaris lumbricoides capture erythrocyte sialic acid and thatglobular suspensions in enzymatic medium, incubated with this parasite, completely lost the ability to aggregate. The aim of this work was to study the erythrocyte T antigen exposure by A. lumbricoides action on the anionic charge of sialic acid deficient red cells. Studies were done on 48 adult specimen parasite extracts ([AE]) and an L1/ L2 larvae concentrate ([ALLC]: 1300-1500 larvae/mL). Group O red cells in bromelain enzymatic medium (RCB) and Control erythrocytes in saline medium (RCC) were used. The RCB sediment was incubated with an equal volume of [AE]/ [ALLC] and the RCC sediment with physiological solution during 120 minutes at 37 ºC. Plate and Tube Agglutination Tests were performed, contrasting RCB and RCC with adult and cord human sera. The results showed that 33.33% of the RCB incubated with [AE] and 66.67% of the RCB incubated with [LCAL] agglutinated with serum from adult, but not cord serum. RCB were not agglutinated with any of the sera. It is the first time that erythrocyte T antigen exposure by a parasite action is communicated. T activation could produce autoagglutination and haemolysis in the adult and would represent a transfusion risk factor in the child population.

A poliaglutinabilidade dos glóbulos vermelhos pode ser resultado do desmascaramento do antígeno críptico T devido à ação de neuraminidases microbianas que eliminam resíduos terminais de ácido siálico na membrana da hemácia. Em experiências preliminares foi demonstrado que Ascaris lumbricoides capta ácido siálico do eritrócito e que as suspensões globulares em meio enzimático, incubadas com esta parasita, perdem totalmente a capacidade de agregação. O objetivo foi estudar a exposição do antígeno T eritrocitário, por ação de A. lumbricoides sobre a carga aniônica de glóbulos vermelhos deficientes em ácido siálico. Trabalhou-se com 48 extratos de exemplares adultos da parasita ([EA]) e um concentrado de larvas L1/ L2 ([CLAL]):1300-1500 larvas/mL). Foram utilizados eritrócitos Grupo O em meio enzimático de bromelina (GVB) e eritrócitos Controle em meio salino (GVC). O sedimento globular de GVB foi incubado com igual volume de [EA]/ [CLAL] e o de GVC com solução fisiológica durante 120 minutos a 37 ºC. Foram realizados Testes de Aglutinação em Placa e em Tubo, enfrentando os GVB e GVC a soros humanos de adulto e de cordão. Os resultados mostraram que 33,33% dos GVB incubados com [EA] e 66,67% dos GVB incubados com [CLAL] aglutinaram com soro de adulto, mas não com soro de cordão. Os GVC não aglutinaram com nenhum dos soros. É a primeira vez que se comunica a exposição do antígeno T eritrocitário por ação de uma parasita. A ativação T poderia produzir autoaglutinação e hemólise no homem adulto e representaria um fator de risco transfusional na população infantil.

Ascaris lumbricoides: Mimetismo molecular por absorción de epitopes P1 / Ascaris lumbricoides: Molecular mimicry by P1 epitope absorption

El mimetismo molecular se ha asociado con la cronicidad de las infecciones parasitarias. Este mecanismo puede deberse a absorción de moléculas del hospedador o a síntesis de moléculas similares. P1 ha sido detectado en diversas especies parásitas. Experiencias previas han demostrado epitopes P1 en ejemplares adultos de Ascaris lumbricoides. El objetivo de este trabajo fue estudiar la absorción de estos epitopes por estadios larvales del nematodo, a los fines de determinar el mecanismo de expresión de estos antígenos sobre la cutícula parasitaria. Las larvas fueron eclosionadas a partir de heces con huevos de este helminto. Fueron cultivadas en medio RPMI con eritrocitos P1. Se realizó la Técnica de Inhibición de la Aglutinación Semicuantitativa usando cuatro anticuerpos monoclonales anti-P1. El sistema revelador fue una suspensión de eritrocitos frescos P1 en medio enzimático de bromelina. Se investigaron por la misma técnica productos de excreción-secreción símil P1 usando larvas cultivadas en medio RPMI en ausencia de eritrocitos P1. Las larvas cultivadas con glóbulos rojos inhibieron la aglutinación de todos los anticuerpos monoclonales con los eritrocitos P1. No se identificaron productos de excreción- secreción símil P1. Se ha demostrado que las larvas de A. lumbricoides absorben epitopes P1 del medio de cultivo. Se concluye que el parásito puede absorber este antígeno durante su ciclo de vida para usarlo en el mimetismo molecular.

Molecular mimicry has been associated with chronicity of parasitic infections. This mechanism can be due to absorption of the host's molecules or to synthesis of similar molecules. P1 has been detected in various parasite species. Previous experiences have shown P1 epitopes in Ascaris lumbricoides's adult parasites. The aim of this study was to analyse absoption of these epitopes by nematode larvae in order to determine the mechanism by which the parasite can express these antigens on their cuticle. Larvae were hatched from the faeces with helminth eggs. Larvae were cultivated in RPMI medium with P1 red cells. The Quantitative Inhibition Agglutination Test was performed using 4 anti- P1 monoclonal antibodies. P1 fresh red cells in bromelin enzymatic medium was used as revealing system. Simil P1 excretory-secretory products were investigated using larvae cultivated in RPMI medium without P1 erythrocytes by the same technique. The larvae which were cultivated with red cells inhibited the agglutination between all anti- P1 monoclonal antibodies and P1 erythrocytes. Simil P1 excretory-secretory products were not identified. It was demonstrated that A. lumbricoides larvae absorb P1 epitopes from the culture medium. It can be concluded that the parasite can absorb this antigen during its life cycle in order to use it in molecular mimicry.

Ascaris lumbricoides: Estudio de la cinética de captación de ácido hialurónico / Ascaris lumbricoides: Study of kinetics of hyaluronic acid capture

El ácido hialurónico (AH) participa de la respuesta inmune porque es un constituyente de las barreras mecánicas naturales, un estimulador de la inflamación y un ligando de receptores involucrados en la inmunidad. En experiencias previas se demostró que adultos y larvas de Ascaris lumbricoides pueden unir AH. El objetivo de este trabajo fue estudiar la cinética de captación de AH por este nematodo. Se trabajó con un extracto de parásito adulto y un concentrado de larvas. Se utilizó la técnica modificada de Inhibición de la Agregación por Adhesión para detección del receptor CD44 soluble de hialuronato. Se evaluó la cinética de captación de AH por el parásito, variando el tiempo de contacto entre ambos desde un tiempo inicial hasta 90 minutos, con intervalos de 10 minutos. Para todos los tiempos se calcularon los valores de CexpAdhE AH e IexpCP AH que fueron analizados por las pruebas de Wilcoxon y de Friedman. Los resultados mostraron que al tiempo inicial de contacto, el parásito adulto y las larvas captan una pequeña cantidad de AH. A los 10 minutos se produjo la mayor captación que se mantuvo sin diferencias significativas durante 50 minutos. A partir de ese tiempo, hubo un leve incremento en la captación que permaneció sin diferencia significativa hasta el tiempo final. Esta experiencia demuestra que in vitro, A. lumbricoides realiza la mayor captación a los 10 minutos de contacto, por lo que se sugiere que in vivo sería capaz de unir AH rápidamente a los fines de modular la respuesta inmune.

Hyaluronic acid (HA) particípales in the immune response because it is a constituent of natural mechanical barriers, an inflammation stimulator and a ligand for receptors involved in immunity. Previous experiences have shown that adult specimens and larval concéntrales oí A. lumbricoides have hyaluronan binding capacity. The aim ofthis work was to study the kinetics ofhyaluronic acid capture by this parasite. Work was carried out with an extract of adult specimen and a larval concéntrate. The modlfled test of serum soluble CD44 Detectlon by Aggregatlon Inhlbltlon was used. Kinetics hyaluronlc acid capture by the nematode was assessed by varylng the contad time between HA and parasite, from an initial time to 90 minutes, with 10-minute intervals. CexpAdhE HA ana lexpCP HA were calculated for all the times and they were analysed by Wilcoxon and Friedman Tests The results showed that at initial time of contad, the adult paraslte and the larvae had captured a small amount of HA. The major capture was made at 10 minutes and it was maintained for 50 minutes without significad differences. From that time there was a slight increase in capture and it remaíned so untíi the end of the experiment without considerable variations. This experience demonstrates that at 10 minutes of in vitro contad, A. lumbricoides captures most of the HA, whích suggests that in vivo, the parasite would be able to capture HA quickly for the purpose of modulating the immune response.

Estudio de la captación de ácido hialurónico por Ascaris lumbricoides / Study of hyaluronic acid capture by Ascaris lumbricoides

El ácido hialurónico (AH) tiene importantes funciones en la inmunidad. En experiencias previas se demostró que extractos de adultos de A. lumbricoides y concentrados larvarios, tienen capacidad de unión a AH. El objetivo de este trabajo fue estudiar la captación de AH por este helminto. Se trabajó con tres extractos del parásito adulto ([EA]B,C,D) y 3 concentrados de larvas ([CLAL1]: 1100 a 1200 larvas/ mL; [CLAL2]: 400 a 600 larvas/ mL y [CLAL3]: 100 a 200 larvas/ mL). Se empleó la técnica modificada de Inhibición de la Adhesión para detección del Receptor CD44 soluble de hialuronato en suero humano. Se definió CexpAdhE AH como el cociente entre los eritrocitos adheridos por el AH en presencia y ausencia del parásito y se definió IexpCP AH, como la cantidad de eritrocitos que se dejaron de adherir debido a la captación de AH por el parásito, referido al número total de eritrocitos. Los resultados mostraron diferencias significativas en CexpAdhE AH y en IexpCP AH, por efecto de la concentración larvaria y del [EA]. Las medias aritméticas de CexpAdhE AH y de IexpCP AH para los concentrados larvarios fueron 0,636 y 0,21 ([CLAL1]); 0,819 y 0,068 ([CLAL2]); 0,97 y 0,013 ([CLAL3]). Las medianas de CexpAdhE AH y de IexpCP AH para los extractos fueron [EA]C 0,275 y 0,4; [EA]B: 0,20 y 0,43; [EA]D: 0,075 y 0,495. La experiencia permitiría suponer que el parásito puede captar AH para interferir en la respuesta inmune del hospedador.

Hyaluronan Acid (HA) has important functions in immunity. Previous experiences have shown that A. lumbricoides's extracts of adult specimens and larval concentrates have hyaluronan binding capacity. The aim of this study was to analyse the HA capture by this helminth. Three extracts of adult specimens ([AE]B,C,D) and 3 larval concentrates ([ALLC1]: 1100 to 1200 larvae/ mL; [ALLC2]: 400 to 600 larvae/ mL and [ALLC3]: 100 to 200 larvae/ mL) were studied. The modified test of serum soluble CD44 Detection by Aggregation Inhibition was used. CexpAdhE AH was defined as the quotient between erythrocytes adhered by the HA in presence and in absence of the parasite, and IexpCP AH was defined as the amount of erythrocytes that stopped adhering due to the HA capture by the parasite in relation to the total number of erythrocytes. The results showed significant differences in CexpAdhE AH and IexpCP AH as the result of larvae concentration and of the extracts. The arithmetic means of CexpAdhE AH and IexpCP AH for the larvae were 0.636 and 0.21 ([ALLC1]); 0.819 and 0.068 ([ALLC2]); 0.97 and 0.013 ([ALLC3]). Medians of CexpAdhE AH and IexpCP AH for the extracts were [EA]C:0.275 and 0.4; [EA]B: 0.20 and 0.43; [EA]D: 0.075 and 0.495. From the experience, it could be assumed that the parasite can capture the HA to interfere in the host's immune response.

Host immune response to Toxoplasma gondii and Ascaris lumbricoides in a highly endemic area: evidence of parasite co-immunomodulation properties influencing the outcome of both infections

Toxoplasmosis and ascaridiasis evoke polar Th-1 and Th-2 host immune responses, respectively. A study to investigate the specific cytokine profile production by in vitro cultures of peripheral blood mononuclear cells from individuals living under precarious sanitary conditions in a highly endemic area for the parasites Toxoplasma gondii and Ascaris lumbricoides was conducted. High levels of both IFN-³ (Th-1) and IL-13 (Th-2) were observed in groups of co-infected individuals presenting toxoplasmic ocular lesions. Significantly lower IL-10 and TGF-² levels were produced by co-infected individuals in comparison with groups of individuals not infected with A. lumbricoides and either positive or negative for T. gondii living under good sanitary conditions (control groups). The possible influence of co-parasitism on the clinical presentation of ocular toxoplasmosis is discussed.

Estados larvales de ascaris lumbricoides: capacidad de unión a ácidos hialurónico / Larval stages of ascaris lumbricoides: hyaluronan binding capacity

El ácido hialurónico tiene importantes funciones en los procesos inflamatorios y de reparación tisular. Debido a la variedad de estrategias utilizadas por los parásitos para evadir la respuesta inmune del hospedador y las múltiples funciones e importancia fisiológica del ácido hialurónico, el objetivo fue estudiar la capacidad de unión a ácido hialurónico de estados larvarios de A. lumbricoides Se trabajó con 4 Concentrados de Larvas obtenidas de la eclosión de huevos de A. lumbricoides y recolectadas por el método de Baermann. Se modificó la técnica de detección de CD44 soluble en suero por Inhibición de la Agregación por Adhesión. Se observó que los 4 Concentrados Larvales unían ácido hialurónico. Los resultados obtenidos permiten suponer la existencia de un receptor con especificidad para ácido hialurónico en A. lumbricoides. Este receptor eventualmente podría competir con los receptores habituales del hospedador. El parásito podría utilizar este mecanismo para evadir la respuesta inmune

Hyaluronic acid has important functions in inflammatory and tissue reparation processes. Owing to the varied strategies of the parasites to evade the host´s immune response, as well as the multiple functions and physiological importance of hyaluronic acid, the aim was to study the hyaluronan binding capacity by Ascaris lumbricoides larval stages. Larval concentrates were prepared by hatching A. lumbricoides eggs. The larvae were collected by the Baermann method. The test of serum soluble CD44 detection by Agregation Inhibition was modified. All the larval concentrates presented hyaluronan binding capacity. The obtained results allow to suppose the existence of an hyaluronic acid specific receptor in A. lumbricoides. This receptor eventually might compete with the usual receptors of the host. The parasite might use this mechanism to evade the immune response

Ascaris lumbricoides: Capacidad inhibitoria relacionada al antígeno P1 / Ascaris lumbricoides: Inhibitory capacity in relation to P1 antigen

El Sistema de Grupo Sanguíneo P tiene un único antígeno: P1 que fue identificado en varias especies parásitas. El objetivo de este trabajo fue determinar la capacidad inhibitoria de A. lumbricoides en relación al antígeno P1. Se trabajó con 11 extractos parasitarios (EA). Para evaluar la capacidad inhibitoria de los extractos en relación a los epitopes P1, se realizó la técnica semicuantitativa de inhibición de la aglutinación. Se prepararon dos series de diluciones de anticuerpo monoclonal anti- P1; a la primera se le agregó PBS a todos los tubos y a la otra, igual volumen de EA. El sistema revelador fue una suspensión de eritrocitos P1. Se determinó el título del anticuerpo monoclonal en ambas series. Se consideró significativa la aglutinación cuando hubo una diferencia de 2 o más diluciones entre ambos títulos. De los 11 EA estudiados, 8 presentaron epitopes P1. A estos 8 extractos se les calculó el Poder Inhibitorio y se lo relacionó con su contenido proteico a los fines de poder comparar la capacidad inhibitoria entre los extractos. La técnica aplicada permitió evidenciar la presencia de epitopes del Sistema P en extractos de A. lumbricoides y comparar la capacidad inhibitoria de los extractos en relación a epitopes P1.

P Blood Group has a unique antigen: P1. It was identified in various parasite species. The aim of this work was to determine A. lumbricoides´s Inhibitory Capacity in relation to P1 antigen. The work was based on 11 parasite extracts (AE). The semiquantitative inhibition agglutination technique was used to assess the extracts´ Inhibitory Capacity in relation to P1 antigen. Two series of anti- P1 monoclonal antibody dilutions were prepared. PBS was added to the first series and an equal volume of AE to the second. Suspensions of P1 red cells were used as a revealing system. Monoclonal antibody titres were determined in both series. The agglutination was considered significative when there was a difference of two or more dilutions between the titres. Eight of the 11 extracts studied presented P1 epithopes. Inhibitory power of these 8 extracts was calculated and it was related with their protein concentrations to compare the Inhibitory Capacity among the extracts. The technique used made it possible to prove P System epithopes presence and to compare the extracts´ Inhibitory Capacity in relation to P1 epithopes.

Intestinal helminthes and/or Toxocara infection are unrelated to anti-HBs titers in seven-year-old children vaccinated at birth with recombinant hepatitis B vaccine

The aim of this investigation was to evaluate the possible effect of nematode infection on anti-HBs antibody levels in the serum of seven-year-old schoolchildren vaccinated at birth with the recombinant hepatitis B vaccine. Anti-HBs and anti HBc antibodies were evaluated in the sera of 100 schoolchildren with at least one intestinal nematode and/or a positive serological reaction for anti-Toxocara antibodies and in 95 schoolchildren without intestinal helminthiasis or serum anti-Toxocara antibodies. Both groups were from public elementary schools located on the urban periphery of Vitória, ES, Brazil. Among these 195 children, the median anti-HBs antibody titer was 31.3IU/ml and the frequency of titers less than 10IU/ml was 33.8 percent (95 percent CI: 27.1-40.4 percent). There were no significant differences between the medians of anti-HBs titers or the frequency of titers less than 10IU/ml between the groups with or without helminthes (29.5 and 32.9IU/ml and 33 and 34.7 percent, respectively; p>0.05). Even when the children with intestinal nematodes and/or anti-Toxocara antibodies and with blood eosinophil counts over 600/mm³ were compared with children without infection from intestinal nematodes and without anti-Toxocara antibodies, with blood eosinophil counts less than 400 eosinophils/mm³, these differences were not significant. None of the children presented anti-HBc antibodies. In conclusion, infections with intestinal nematodes and/or the presence of anti-Toxocara antibodies did not interfere with the anti-HBs antibody titers in seven-year-old children vaccinated at birth with the recombinant hepatitis B vaccine.

O objetivo dessa investigação foi avaliar um possível efeito de infecções por nematóides sobre os níveis de anticorpos anti-HBs no soro de escolares de sete anos de idade, vacinados ao nascer com a vacina recombinante para hepatite B. Anticorpos anti-HBs e anti-HBc foram avaliados no soro de 100 escolares portadores de pelo menos um nematóide intestinal e/ou uma reação sorológica positiva para anticorpos anti-Toxocara e em 95 escolares sem helmintíases intestinais e sem anticorpos séricos anti-Toxocara, todos matriculados em escolas primárias públicas situadas na periferia urbana de Vitória, ES, Brasil. Nas 195 crianças, a mediana dos títulos dos anticorpos anti-HBs foi 31,3UI/ml, e a freqüência de títulos inferiores a 10UI/ml foi de 33,8 por cento (IC a 95 por cento:27,1- 40,4 por cento). Não houve diferença significativa entre as medianas dos títulos de anti-HBs ou da freqüência de títulos inferiores a 10 UI/ml entre as crianças com ou sem helmintos (29,5 e 32,9 UI/ml e 33 e 34,7 por cento, respectivamente; p >0.05). Mesmo quando comparadas crianças com nematóides intestinais e/ou anticorpos anti-Toxocara com eosinófilos circulantes acima de 600/mm³, com crianças sem infecção com nematóides intestinais e sem anticorpos anti-Toxocara, com menos de 400 eosinófilos/mm³, aquelas diferenças não foram significativas. Nenhuma das crianças apresentou anticorpos anti-HBc. Em conclusão, infecções com nematóides intestinais e/ou presença de anticorpos anti-Toxocara não interferem nos títulos de anticorpos anti-HBs em crianças de sete anos de idade, vacinadas ao nascer com a vacina recombinante para hepatite B.

Total IgE level in respiratory allergy: study of patients at high risk for helminthic infection

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.

H antigen presence in an Ascaris lumbricoides extract

Experiencias previas han demostrado los mismos antígenos del Sistema ABO y del Sistema P en extractos de A. lumbricoides y en sus huéspedes. El objetivo fue mostrar el comportamiento de un extracto de A. lumbricoides de un paciente Grupo O frente a anticuerpos monoclonales de diferentes especificidades. Se hicieron pruebas de Inhibición de la Aglutinación enfrentando el extracto contra anticuerpos monoclonales (anti A 2.23; anti B 2.54; anti B 2.62; anti AB 2.39 y anti H 2.72) en dosis óptimas. El sistema revelador fue una suspensión fresca de eritrocitos Grupo O. El extracto sólo inhibió la aglutinación de anti H 2.72 con eritrocitos O. Se hizo la inhibición de la aglutinación semicuantitativa del extracto frente a dos series de diluciones de anti H 272 usando eritrocitos frescos Grupo O como sistema revelador. Se observó una diferencia de 5 diluciones entre los títulos de ambas series y se confirmó significativamente la presencia de antígeno H en el extracto. La no inhibición de la aglutinación del extracto frente a anti A, anti B y anti AB ha corroborado nuestras observaciones previas sobre ausencia de epitopes A y B en extractos de pacientes Grupo O. Los resultados de los estudios previos y de esta experiencia, han demostrado la importancia de los glicoconjugados de membrana en A. lumbricoides, los que podrían estar involucrados en el mimetismo antigénico para este parásito.

Human toxocariasis and ascariasis: concomitant parasitism in Srinagar, Kashmir, India.

Human toxocariasis caused by Toxocara canis is common in both developing and developed countries and leads to visceral larva migrans with high morbidity and mortality. Ascariasis caused by Ascaris lumbricoides, too has global distribution and in India, high prevalence rate has been reported in Kashmir (J & K State). Both nematode parasites, Toxocara canis and A. lumbricoides require similar biological and environmental conditions for the development of eggs in soil. Therefore, the present study was attempted to detect the antibody response to T. Canis excretory-secretory (ES) antigen by enzyme linked immunosorbent assay in patients attending Sher-I-Kashmir Institute of Medical Sciences, Soura, Srinagar, Kashmir to assess the magnitude of human toxocariasis in Kashmir, the highly endemic area of ascariasis. Interestingly, it was observed that 38 (82.60%) out of 46 patients harbouring Ascaris Iumbricoides had positive antibody response to T. Canis ES antigen while none of the 15 normal healthy subjects from the same endemic zone, 25 from low endemic zone Chandigarh and 15 from other parasitic infections (hookworm, hydatidosis, cysticercosis) indicated detectable positive response. Majority of the ascariasis positive patients studied were in the age group of 21-40 years. However, one ascariasis patient studied in the age group of 1-10 years (4 years old) had also positive antibody response to T. Canis antigen. This study is the first report of human toxocariasis in Kashmir, India, an endemic zone for ascariasis and emphasizes the need for detailed epidemiological study for the ultimate prevention and control of this disease

Incidencia de parasitosis intestinales en pacientes pediátricos hematoncológicos de 1 a 15 años de edad / Frequent intestinal parasites in the hematologic patients

Introducción. Se hace referencia a los parásitos intestinales más frecuentes en los pacientes hematoncológicos y la asociación con desnutrición. Material y método. En la Unidad de Pediatría del Hospital General de México SSA, se estudió en forma prospectiva, observacional y descriptiva a un grupo de 85 pacientes hematoncológicos, provenientes de la consulta externa, con o sin síntomas parasitarios. Los pacientes se atendieron entre junio y diciembre de 1994. A todos se les realizaron estudios coproparasitoscópicos en serie de tres, por el método de Faust. Resultados. Se estudió un total de 85 niños de 1 a 15 años de edad; 59 se encontraron parasitados (69.5 por ciento) y 26 (30.5 por ciento) libres de parásitos. Conclusiones. Las afecciones más frecuente fueron: leucemia, tumores del sistema nervioso central y linfomas. Los parásitos más frecuentes fueron: Giardia lamblia, 28.7 por ciento, Entamoeba histolytica 26 por ciento, Ascaris lumbricoides 12.3 por ciento. De los 59 pacientes con algún parásito, 54 (91.4 por ciento) cursaron con algún grado de desnutrición

Histological changes in hamster liver by ES antigen of Ascaris suum.

Polyacrylamide gel electrophoresis with SDS (PAGE-SDS) of the ES antigens of A. suum revealed several protein molecules which differed from those obtained in ES antigens of A. lumbricoides. Nature of liver damage caused by ES antigens of A. suum was studied in hamsters to find out the nature of damage and to compare with those caused by ES antigens of A. lumbricoides. Feeding of ES antigens of A. suum was carried out in 7 hamsters for 75 days. After such feeding gross hepatic damage was noticed. This was characterized by pericentrivenular degeneration and necrosis of liver parenchyma, the lesions being different and much more severe than those observed in hamster challenged by ES products of A. lumbricoides. The lesions appear to be immune mediated.