Bancroftian filariasis in Kwale District of Kenya. III. Quantification of the IgE response in selected individuals from an endemic community

Estambale, Benson B.; Simonsen, PE; Vennervald, BJ; Knight, R.; Bwayo, JJ

doi:10.1080/00034983.1995.11812954

Cited by 10 publications

(8 citation statements)

References 23 publications

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“…Our goal was to define further the role played by basophils in the immune response to filarial infections in humans. Specifically, we sought to: 1) confirm that basophils from filaria-infected patients are activated by filarial Ag; 2) determine whether Brugia malayi Ag (BmAg) 2 can nonspecifically activate basophils from uninfected individuals; and 3) assess the contribution of basophils to the IL-4 pool in filaria-infected patients relative to CD4 ϩ T cells in terms of both frequency of IL-4-producing cells and actual amounts of IL-4 produced. were expatriates and 9 were immigrants from countries endemic for filarial infections.…”

mentioning

confidence: 99%

Parasite Antigen-Driven Basophils Are a Major Source of IL-4 in Human Filarial Infections

Mitre

Taylor

Kubofcik

et al. 2004

The Journal of Immunology

101

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Basophil contribution to the IL-4 pool in filarial infections was assessed using PBMC from 20 patients with active filarial infections and from 9 uninfected subjects. Patient basophils released histamine in response to Brugia malayi Ag (BmAg). They also released IL-4 within 2 h after exposure to BmAg, as assessed by intracellular cytokine flow cytometry. This IL-4 induction was Ag specific, as IL-4 was not detected in BmAg-exposed basophils obtained from uninfected subjects. Although there were, on average, 64 times more CD4+ T cells than basophils in the peripheral circulation of filaria-infected patients, the absolute numbers of basophils and CD4+ T cells producing IL-4 per 100,000 PBMC were equivalent (geometric mean: 16 IL-4-producing basophils/100,000 PBMC vs 22 IL-4-producing CD4+ T cells/100,000 PBMC). Basophils also released IL-4 in response to both low and high concentrations of BmAg, whereas CD4+ T cells released IL-4 only after incubation with a high concentration of BmAg, raising the possibility that basophils, due to their lower threshold for activation, may actually release IL-4 more frequently than CD4+ T cells in vivo. Furthermore, IL-4 production in vitro by Ag-stimulated purified basophils or CD4+ T cells provided evidence that basophils release greater quantities of IL-4 per cell than CD4+ T cells in response to BmAg. These results suggest that, when Ag-specific IgE is present in a filaria-infected individual, basophils function to amplify the ongoing Th2 response by releasing IL-4 in greater amounts and possibly more frequently than CD4+ T cells in response to filarial Ag.

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mentioning

confidence: 99%

Parasite Antigen-Driven Basophils Are a Major Source of IL-4 in Human Filarial Infections

Mitre

Taylor

Kubofcik

et al. 2004

The Journal of Immunology

101

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“…For dracunculiasis and other helminth infections, it has been suggested that protective immune responses in the host may be blocked by specific IgG4 (and possibly IgG1) if sharing specificity with protective specific IgE antibodies, and by nonspecific IgE if occupying Fc receptors on effector cells (especially eosinophils, monocytes, and B lymphocytes) of the immune system. [4][5][6][7][8][9][10][11] It is possible that increased production of D. medinensis-specific IgG1 and IgG4 around the time of patency play a role in the blocking of protective immune responses, which would otherwise (e.g., in endemic normal individuals) have killed ingested infective larvae. Thus, adult female worms (or newly ingested infective larvae) may have induced these responses as a mechanism for blocking a protective response towards reinfection.…”

Section: Discussionmentioning

confidence: 99%

“…4,5 Human sera were optimally diluted 1:50 or 1:500 and capture antiserum (rabbit-anti-human IgE; Dako) and detection antiserum (HRP-labeled rabbit-anti-human IgE; Dako) were optimally diluted 1:1,000.…”

Section: Study Individuals and Study Designmentioning

confidence: 99%

Immunoepidemiology of Dracunculus medinensis infections II. Variation in antibody responses in relation to transmission season and patency.

Bloch

Simonsen²

1998

The American Journal of Tropical Medicine and Hygiene

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Abstract. The serum antibody responses (specific IgG1, IgG4, and IgE, and total IgE) to Dracunculus medinensis infection in humans from a highly endemic area of northern Ghana were examined regularly by ELISA over a period of one year in cohorts of individuals who developed a patent D. medinensis infection during the study period (actively infected category), or who claimed to have never had a patent infection (endemic normal category). The results were analyzed in relation to seasonality and time of patency of infection. For individuals in the actively infected category, a clear seasonal variation in the mean levels of specific IgG1 and IgG4 was found, with the highest levels late in the dry season and early in the rainy season, when transmission is high, and the lowest levels late in the rainy season and early in the dry season. Endemic normal individuals responded with low and fluctuating levels of specific IgG1 and with low and nonfluctuating levels of specific IgG4. For specific and total IgE, no seasonal variation was observed in any of the two infection status categories. In relation to time of patency of infection (only involving the category of actively infected individuals), the mean levels of specific IgG1 and IgG4 increased from two months before patency of infection, peaked during patency, and then gradually decreased for four months until a constant level was reached. No significant fluctuations in the levels of specific and total IgE were observed in relation to time of patency. The present study thus showed extensive variation in levels of D. medinensis-specific IgG1 and IgG4 (but not IgE) over time. Seasonal variations in antibody responses may also occur in other helminth infections, especially those with seasonal transmission, and these should be taken into consideration when interpreting the results of immunologic studies.The existence of a distinct transmission season of dracunculiasis provides an ideal opportunity to describe variations in the humoral immune responses of infected individuals in relation to seasonality, or in relation to the time of patency of infection. In a previous study from northern Ghana, it was observed that people living in a dracunculiasis endemic area had levels of Dracunculus medinensis-specific antibodies (total, IgG1, and IgG4) during the time of patency, which were significantly higher than the levels measured in the same individuals eight months later, except for a few individuals who had developed a new patent infection. 1 Furthermore, in rhesus monkeys infected with D. medinensis, the levels of antibodies specific to D. medinensis first-stage larvae increased from three to seven months after infection and peaked around the period of patency of infection. 2 These studies indicate that the levels of specific antibodies vary over time during the course of infection. Nothing is known about the variation in the production of antibodies over time in people claiming to have never had a patent D. medinensis infection despite living in a highly endemic area.To examin...

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“…Moreover, for Bancroftian filariasis and schistosomiasis, it has been shown that dual recognition of antigens by IgG4 and IgE is common and that the antigenic determinants can be blocked by specific IgG4 when specific IgG4 and IgE are both present. 8,[11][12][13][14] Thus, a protective immune response may be effectuated by specific IgE but regulated by nonspecific IgE and/or specific IgG4.…”

Section: Interrelationship Between the Different Types Of Antibody Rementioning

confidence: 99%

“…The total IgE concentrations in sera were measured by a sandwich ELISA procedure as described previously with only minor modifications. 8 Rabbit anti-human IgE (Dako) was used at a concentration of 3.9 g/ml corresponding to a dilution factor of 1:2,000. After blocking with phosphate-buffered saline containing 0.1% Tween 20 and 0.5% bovine serum albumin for 1 hr at room temperature, 100 l of the following were applied to each plate: 1) a two-fold serial dilution of a standard human IgE (total IgE control; Kabi Pharmacia Diagnostics) from 0.08 l/ml to 0.000625 g/ml, and 2) test serum samples in dilutions of 1:50.…”

Section: Study Individuals and Study Designmentioning

confidence: 99%

Immunoepidemiology of Dracunculus medinensis infections I. Antibody responses in relation to infection status.

Bloch

Simonsen²

1998

The American Journal of Tropical Medicine and Hygiene

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Abstract. The specific serum IgG1, IgG4, and IgE responses to Dracunculus medinensis and the level of total IgE of individuals living in a highly endemic area of northern Ghana were measured by ELISA. Sera were obtained in the high transmission season from individuals with prepatent, patent, or postpatent infection as well as from individuals from the same endemic area who claimed to have never had a patent infection (i.e., endemic normal individuals). Individuals with prepatent or postpatent infections responded with a significantly lower mean level of specific IgG1 and IgG4 compared with individuals with a patent infection, and with a significantly higher mean level of specific IgG1 and IgG4 compared with endemic normal individuals. For specific IgE, no differences were found in the mean antibody level between the infection status categories. Individuals with a patent infection had a significantly lower mean serum level of total IgE compared with prepatent, postpatent, and endemic normal individuals. Endemic normal individuals had the highest mean level of total IgE. Furthermore, in all clinical categories, high responders for specific IgG1 and IgG4 generally had low levels of total IgE, whereas low responders for specific IgG1 and IgG4 generally had high levels of total IgE. A similar dichotomy, although less distinct, was observed between specific IgG1 and IgG4 on the one hand and specific IgE on the other. Thus, similar to what has been suggested for schistosomiasis and lymphatic filariasis, the relationship between the IgG subclasses and IgE appears to play a role in, or at least to reflect, a mechanism for protective immunity in dracunculiasis.Human infections with Dracunculus medinensis (guinea worm) occur in parts of West and Central Africa and in Yemen and India. 1 The 10-12-month prepatent period is asymptomatic except for the last 1-2 weeks during which the adult female worm reaches subcutis and prepares for penetration of the body surface. At this late stage, the worm becomes palpable in the skin and a blister develops around its anterior end, thus making the patient aware of the infection. 2,3 Currently, no reliable method exists for diagnosis of dracunculiasis in the asymptomatic part of the prepatent period.Dracunculus medinensis induce vigorous humoral immune responses in infected individuals. 4-7 However, little is known about the relationship between the humoral responses and infection status (i.e., prepatent, patent, postpatent and those claiming to have never had a patent infection). Briefly, previous studies indicated that individuals in a prepatent and patent stage of infection responded similarly with total specific immunoglobulins, 4 and individuals in a patent and postpatent stage responded similarly with total specific immunoglobulins and specific IgG1, IgG4, and IgE. 5 Sera from endemic normal individuals (claiming to have never had a patent D. medinensis infection despite living in a highly endemic area) responded only weakly with specific IgG1 and IgG4 compared with individuals with...

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Bancroftian filariasis in Kwale District of Kenya. III. Quantification of the IgE response in selected individuals from an endemic community

Cited by 10 publications

References 23 publications

Parasite Antigen-Driven Basophils Are a Major Source of IL-4 in Human Filarial Infections

Parasite Antigen-Driven Basophils Are a Major Source of IL-4 in Human Filarial Infections

Immunoepidemiology of Dracunculus medinensis infections II. Variation in antibody responses in relation to transmission season and patency.

Immunoepidemiology of Dracunculus medinensis infections I. Antibody responses in relation to infection status.

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