Stable marital relationship protects men from oral and genital HPV infections.

Human papillomavirus (HPV) infections are associated with sexual behavior. Changes in the sexual habits of couples and their impact on male genital and oral HPV infections were determined during 7 years of follow-up (FU). At baseline and 7 years FU, urethral, semen/penile, and oral samples were collected from 46 men and cervical and oral samples of their spouses for HPV DNA detection. Demographic data and risk factors of spouses were recorded by questionnaire at both time points and analyzed for concordance. HPV genotyping was done with the Multimetrix® kit. At baseline, 29.5 % of the male genital and 11 % of their oral samples tested positive. Incident genital HPV infection was found in 23 % and oral infection in 10.9 % of men. Genotype-specific persistence was detected in one man (HPV53) in genital samples. Moderate to almost perfect concordance of changes in sexual habits during FU among spouses were found. Changing partners [p = 0.028; odds ratio (OR) = 15; 95 % confidence interval (CI) 1.355-166.054] and marital status (p = 0.001; 95 % CI 0.000-0.002) increased the risk of incident genital HPV infections. The overall outcome of genital HPV disease in men was linked to the frequency of sexual intercourse (p = 0.023; 95 % CI 0.019-0.026) and changes in marital status (p = 0.022; 95 % CI 0.019-0.026), while oral HPV infections were associated with the number of sexual partners (p = 0.047; 95 % CI 0.041-0.052). Taken together, asymptomatic genital HPV infections among the men were common. The risk of incident genital HPV infections increased among men reporting a change of sexual partner during FU, implicating that a stable marital relationship protects against oral and genital HPV infection.

Evaluation of fungal extracts to determine immunomodulatory properties.

BACKGROUND: Immunoglobulin E-mediated allergies have doubled in prevalence during recent decades in developed countries.This increase has been attributed, in part, to high hygiene standards, which have reduced exposure to microbes. The capacity of microbes to induce type 1 helper T cell (TH1) responses may imply suppression of TH2 responses. However, little research has been performed with fungal extracts. OBJECTIVES: To evaluate the TH1-inducing properties of fungal extracts. METHODS: A total of 24 fungal extracts, including Cetavlon-precipitated polysaccharides from different yeasts, molds, and mushrooms were prepared.The extracts were screened for production of interferon (IFN)gamma in human peripheral blood mononuclear cells. The active compounds were further purified by mild acid hydrolysis and by column chromatography and studied in human peripheral blood mononuclear cells. RESULTS: Expression of IFN-gamma was induced by several extracts. The strongest expression of IFN-gamma was induced by Candida albicans. The Cetavlon-precipitated mannans of fungi induced cytokine responses that were similar or superior to those induced by whole extracts, C albicans being the most potent inducer of IFN-gamma. Column chromatography-fractionated mild acid hydrolysis of Calbicans mannan was performed. Fractions containing oligosaccharides of 12-16 mannoses induced production of tumor necrosis factor. CONCLUSIONS: Several fungal extracts induce IFN-gamma. The most promising preparations were yeast-derived oligosaccharides. Further research should be focused on purification and eventual synthesis of the extracts.

Evaluation of Fungal Extracts to Determine Immunomodulatory Properties

Antecedentes: En los países desarrollados, la prevalencia de las enfermedades alérgicas mediadas por la inmunoglobulina E se han duplicado en las últimas décadas. Este aumento ha sido, en parte, atribuido a pautas de higiene excesivas que han reducido la exposición a microbios. La capacidad de los microbios para inducir la respuesta Th1 puede dar lugar a la supresión de la respuesta Th2. En este sentido, la investigación que se ha realizado con extractos fúngicos es escasa. Objetivos: Evaluar las propiedades inmunomoduladoras Th1 que inducen los extractos de hongos. Métodos: Se evaluaron un total de 24 extractos de hongos, incluyendo polisacáridos de diferentes levaduras, mohos y hongos. Se estudió la capacidad de estos extractos de inducir la producción de interferón- ƴ (IFN- ƴ) en células mononucleares de sangre periférica (PBMC) humanas. Los extractos fueron posteriormente sometidos a una hidrólisis ácida suave y a cromatografía en columnas. Resultados: Los extractos procedentes de diferentes levaduras, mohos y hongos indujeron un incremento en la expresión de la producción de IFN- ƴ. La expresión más enérgica fue la provocada por Candida albicans (C. albicans). Los mananos fueron también capaces de conseguir un incremento de la expresión de IFN- ƴ similar o superior a la inducida por los extractos enteros, siendo el manano de C. albicans el más potente de todos ellos. Mediante los estudios de estimulación celular, con fracciones obtenidas por cromatografía del manano C. albicans, se observó que aquellas que contenían oligosacáridos de 12-16 manosas indujeron una mayor producción de TNF. Conclusiones: Son varios los extractos fúngicos capaces de inducir la producción de IFN- ƴ. Los productos más potentes fueron los oligosacáridos derivados de las levaduras. Las investigaciones futuras deberían centrarse en la purificación y síntesis final de los mismos (AU)

Background: Immunoglobulin E–mediated allergies have doubled in prevalence during recent decades in developed countries. This increase has been attributed, in part, to high hygiene standards, which have reduced exposure to microbes. The capacity of microbes to induce type 1 helper T cell (TH1) responses may imply suppression of TH2 responses. However, little research has been performed with fungal extracts. Objectives: To evaluate the TH1-inducing properties of fungal extracts. Methods: A total of 24 fungal extracts, including Cetavlon-precipitated polysaccharides from different yeasts, molds, and mushrooms were prepared. The extracts were screened for production of interferon (IFN) ƴ in human peripheral blood mononuclear cells. The active compounds were further purified by mild acid hydrolysis and by column chromatography and studied in human peripheral blood mononuclear cells. Results: Expression of IFN- ƴ was induced by several extracts. The strongest expression of IFN-􀁡 was induced by Candida albicans. The Cetavlon precipitated mannans of fungi induced cytokine responses that were similar or superior to those induced by whole extracts, C albicans being the most potent inducer of IFN- ƴ. Column chromatography–fractionated mild acid hydrolysis of C albicans mannan was performed. Fractions containing oligosaccharides of 12-16 mannoses induced production of tumor necrosis factor. Conclusions: Several fungal extracts induce IFN- ƴ. The most promising preparations were yeast-derived oligosaccharides. Further research should be focused on purification and eventual synthesis of the extracts (AU)

The usefulness of skin tests to prove drug hypersensitivity.

BACKGROUND: Suspected drug hypersensitivity is common. Only a minority of cutaneous adverse drug reactions (CADRs) are allergic in origin and will reappear after the next exposure. Methods to confirm suspected CADRs are needed and skin testing could serve as one possibility. OBJECTIVES: To analyse the usefulness of skin tests in revealing drug allergy. The relevance of skin test results was evaluated with drug provocation studies. METHODS: During 1989-2001, 947 patients with a history of suspected CADR were examined with skin tests including patch tests (PTs) (826 patients), skin prick tests (SPTs) (935 patients) and photopatch tests (12 patients). The occurrence of positive and negative test reactions to different drugs was correlated with clinical history. Drug provocation was carried out in 246 patients. RESULTS: Antimicrobial drugs were suspected and tested most often. A positive PT reaction to one or more drug was seen in 89 of 826 (10.8%), most often to beta-lactams, clindamycin and trimethoprim. A positive SPT reaction was seen in 10 of 935 (1.1%) patients. Challenge was carried out in 17 patients with positive skin test results. Thirteen of 16 (81.2%) PT positives developed exanthema, three remained negative and one SPT-positive patient developed urticaria. Among skin test negatives, 207 of 229 (90.4%) challenges were negative and 22 of 229 (9.6%) were positive, 12 with exanthema, three with fixed drug eruptions and seven with urticaria. CONCLUSIONS: Skin testing, especially the PT, was a useful screening method to find a cause of CADR if the reaction was exanthema and if antimicrobial, cardiovascular or antiepileptic drugs were suspected. The SPT detected occasional positives with antimicrobials. In cases of fixed drug eruption, PTs performed at the earlier reaction site were useful. When skin tests are negative or dubious, oral challenge should be carried out to confirm the association.

Immediate hypersensitivity to Malassezia furfur and Candida albicans mannans in vivo and in vitro.

BACKGROUND: Elevated and correlative Malassezia furfur (M. furfur) and Candida albicans (C. albicans) mannan-specific IgE have been demonstrated in atopic eczema dermatitis syndrome (AEDS) of the head, neck and shoulder (HNS) region of the skin. The significance of these antibodies in vivo has not been demonstrated. METHODS: Sixty-five AEDS patients with HNS distribution were included. Serum total IgE (S-IgE) and yeast antigen-specific (Cetavlon-purified mannan and whole extract antigens of M. furfur and C. albicans) IgE were measured and skin prick tests (SPT) were performed with the yeast antigens. RESULTS: Mannan-specific IgE and SPT were positive in 51 and 48% of patients with M. furfur and in 42 and 22% with C. albicans, respectively. Whole extract-specific IgE and SPT were positive in 85 and 95% of patients with M. furfur and in 91 and 57% with C. albicans, respectively. The highest correlation between specific IgE and SPT was seen with M. furfur mannan (r = 0.60; P < 0.0001). Both M. furfur mannan-specific IgE (r = 0.76; P < 0.0001) and SPT (r = 0.44; P = 0.0005) correlated with S-IgE. CONCLUSIONS: Mannan-induced immediate hypersensitivity in vivo was demonstrated in SPT. The significant correlation between M. furfur mannan-specific IgE and SPT suggests that mannan is an important allergen in yeast hypersensitive AEDS in vivo.

IgE-binding components of cultured human keratinocytes in atopic eczema/dermatitis syndrome and their crossreactivity with Malassezia furfur.

BACKGROUND: Atopic eczema/dermatitis syndrome (AEDS) patients display immunoglobulin E (IgE) reactivity to several antigens, e.g. saprophytic yeasts as Malassezia furfur. AEDS patients also show IgE autoreactivity towards cells of their own tissue including epidermis. PURPOSE OF THE STUDY: The aim of this study was to investigate the IgE autoreactivity of AEDS patients to cultured keratinocytes and to reveal potential crossreacting epitopes in cultured keratinocytes and M. furfur. MATERIAL AND METHODS: Serum samples of 27 AEDS patients were analyzed, of these 13 were M. furfur radioallergosorbent test (RAST) positive and 14 negative. Four urticaria, three psoriasis, and seven nonatopic patients were included as controls. The studies were performed by using IgE immunoblotting and immunoblotting inhibition methods. RESULTS: Ten IgE-binding protein bands were detected in cultured human keratinocytes by IgE immunoblotting using sera from adult AEDS patients. Anti-keratinocyte IgE antibodies were more associated with elevated S-IgE level than M. furfur RAST. Clear crossreactivity with M. furfur could not be shown. CONCLUSIONS: The possible pathomechanism of anti-keratinocyte IgE antibodies is not due to IgE epitope mimicry of saprophytic yeast and local tissue in AEDS skin.

HLA-DR-dependent increased mannan-induced lymphoproliferative response in atopic eczema dermatitis syndrome.

BACKGROUND: In yeast-sensitive atopic eczema dermatitis syndrome (AEDS), yeast mannan induces highly elevated specific IgE levels and lymphoproliferative responses. In healthy individuals the involvement of both human leukocyte antigen (HLA)-dependent T-cell activation and non-HLA-dependent activation, e.g. by crosslinking of the cell surface mannose receptors, has been suggested. In the present study the HLA dependence and the role of crosslinking in the lymphoproliferative response to mannan in AEDS has been analyzed. METHODS: Twenty patients with AEDS and 12 controls with no history of allergic diseases were included in the study. Mannan from Candida albicans was prepared according to the Cetavlon method. Following isolation using Ficoll-Hypaque, peripheral blood mononuclear cells (PBMC) were incubated with the mannan preparation in the absence and presence of different concentrations of neutralizing anti-HLA antibodies and alpha-methylmannoside for 6 days and proliferative responses were measured by 3H-thymidine incorporation and scintilloradiography. RESULTS: In AEDS patients with elevated mannan-specific serum IgE, the C. albicans mannan induced lymphoproliferation. Mannan-induced lymphoproliferative responses could be inhibited, dose-dependently, by neutralizing anti-HLA-DR, but not anti-HLA-DQ antibodies in AEDS patients and healthy controls. The addition of alpha-methylmannoside, that blocks binding to mannose receptors, inhibited lymphoproliferative responses in a dose-dependent way by 50% only in healthy controls, but not in AEDS patients. Levels of inhibition of the proliferation by alpha-methylmannoside correlated inversely with the yeast- and mannan-specific IgE levels. CONCLUSIONS: These results show that in healthy subjects yeast mannan activates lymphocytes both in an HLA-DR-dependent manner and as a result of direct crosslinking of the cell surface. However, in AEDS the elevated lymphoproliferative response is HLA-DR-dependent, although only a slight proportion of this response results from direct crosslinking.

Systemic ketoconazole is an effective treatment of atopic dermatitis with IgE-mediated hypersensitivity to yeasts.

BACKGROUND: IgE-mediated hypersensitivity to yeasts is often seen in atopic dermatitis (AD) patients, especially when dermatitis is located in the head, neck, and shoulder regions. Two studies have shown the efficacy of ketoconazole in the treatment of this type of AD, in contrast to results of topical treatment. The objective was to assess the clinical efficacy of antifungal treatment in AD in a randomized, double-blind, placebo-controlled study with oral ketoconazole and yeast-specific IgE levels and saprophytic yeast growth monitored simultaneously. METHODS: Eighty patients with AD and positive P. ovale and/or C. albicans RAST/skin prick test results were randomized to receive ketoconazole or placebo for 30 days. The yeast growth of skin and pharynx; P. ovale, C. albicans, andS. cerevisiae RAST; serum total IgE; and the severity of the eczema (SCORAD) were assessed at day 0 and thereafter at 1 and 3 months. RESULTS: A significant improvement was seen in the SCORAD scale in the ketoconazole group at the second visit in comparison to the first visit (P<0.0005; n=36), but not in the placebo group (n=39). Of the individual determinants of the SCORAD, itching (P<0.005), the extent of dermatitis (area percentage), excoriation, lichenification (P<0.01), erythema, papulation, and dryness (P<0.05) improved significantly in the ketoconazole group. In the placebo group, only the extent of dermatitis (area percentage) decreased significantly (P<0.05). In the ketoconazole group, the number of positive P. ovale cultures decreased from 60% to 31% (n=35) compared to the placebo group (64% to 56%; n=39). The clinical response was most significant in female patients with positive yeast cultures. CONCLUSION: Saprophytic yeasts may be a source of allergens in AD. Thus, patients with AD, yeast growth, and elevated IgE levels to yeasts should be offered antifungal treatment.

Pityrosporum and Candida specific and non-specific humoral, cellular and cytokine responses in atopic dermatitis patients.

BACKGROUND: Recent cytokine (RT-PCR, ELISA) analyses of inflammation in atopic dermatitis (AD) have suggested a role for IL-4, IL-5 and IFNgamma. Pityrosporum ovale and Candida albicans are important allergens in some patients with AD of the seborrhoic head, neck and shoulder region. In AD patients, the saprophytic yeasts induce IgE responses while they usually induce TH1 type responses. The cytokine responses induced by yeasts in AD are sparsely investigated. OBJECTIVE: To characterize the P. ovale- and C. albicans-specific and non-specific humoral, lymphoproliferative and cytokine (IL-2, 4, 5 and IFNgamma) responses in AD. METHODS: Fifteen AD patients and seven healthy controls (HC) were included. Ficoll-isolated PBMC were stimulated by PHA and laboratory-generated extracts of P. ovale and C. albicans. Lymphocyte proliferation was measured by 3H-thymidine incorporation and cytokine production by sandwich-ELISAs. The antigen-specific IgG and IgE antibodies were analysed by ELISA and nitrocellulose RAST. RESULTS: Pityrosporum ovale- and C. albicans-specific IgE (both P < 0.001) and P. ovale-induced PBMC proliferation (P < 0.02) were elevated in AD. In general, the IL-4/IFNgamma ratio induced by P. ovale was higher than that induced by C. albicans (P < 0.01). The PHA-induced IL-2 (P < 0.05) and IL-4 responses (P < 0.005), and the C. albicans-induced IL-5 response (P < 0.02) and IFNgamma response (P < 0.01), were elevated in AD. A network of correlations was seen between serum total and the yeast-specific IgE, P. ovale-specific lymphoproliferation, PHA-induced IL-2, IL-4 and IL-5, and C. albicans-induced IL-5. CONCLUSION: The cytokine profiles found in this study support the role of TH0 or TH1 cells by the side of TH2 cells in the pathogenesis of atopic dermatitis. Pityrosporum ovale appears to be associated more with IL-4 responses and C. albicans with IFNgamma responses.

Cross-reacting IgE and IgG antibodies to Pityrosporum ovale mannan and other yeasts in atopic dermatitis.

Atopic dermatitis (AD) patients often demonstrate positive skin prick test results and serum IgE antibodies to a range of different yeasts. This has been thought to be due to cross-reactivity. In this study, the cross-reactivity of IgE and IgG antibodies between mannan and crude antigens of Pityrosporum ovale, Candida albicans, and Saccharomyces cerevisiae and crude antigens of Cryptococcus albidus and Rhodotorula rubra was examined by RAST and ELISA inhibition with two serum pools of AD patients. We found cross-reacting IgE and IgG antibodies. In the IgE response, the main cross-reacting pattern was the mannan region, although inhibition could be achieved also with crude antigens of C. albicans, S. cerevisiae, and, to some extent, C. albidus. P. ovale was the most potent inhibitor of IgE-binding components, and against it the highest IgE antibody levels were detected in AD serum pools. In contrast, C. albicans was found to be the most important inducer of IgG antibodies, since the IgG level against P. ovale mannan in both AD serum pools was very low. Cross-reacting antibodies were also seen in ELISA inhibition with both crude and mannan antigens, but since the IgG antibody level of P. ovale mannan in AD serum pools was low, further studies are needed to confirm the IgG results.

IgE, IgA, and IgG responses to common yeasts in atopic patients.

This study was undertaken to analyze the differences in exposure and sensitization to five common environmental yeasts. The responses of IgG, IgA, and IgE to Candida albicans, C. utilis, Cryptococcus albidus, Rhodotorula rubra, and Saccharomyces cerevisiae and purified S. cerevisiae enolase were analyzed by immunoblotting (IgE-IB), and the cross-reactivity of their IgE-binding components by IgE-IB inhibition. Twenty atopic subjects, with asthma, allergic rhinitis, or atopic dermatitis were included. In skin prick tests (SPT), 12 of the patients showed simultaneous reactivity to at least two of the five yeasts, four reacted to one of the yeasts, and four had no responses. Antigens run in SDS-PAGE and transferred to nitrocellulose were probed with enzyme-labeled IgA-, IgG-, and IgE-specific antibodies. The IgE immunoblotting revealed most IgE-binding bands in C. albicans (11 bands) followed by C. utilis (eight bands), S. cerevisiae (five bands), R. rubra (five bands), and Cr. albidus (four bands). Six of the IgE-binding bands of C. albicans and C. utilis shared molecular weight, and only two bands shared molecular weight with other yeasts. These were the 46-kDa band, shared by all five yeasts, and a 13-kDa band shared by four yeasts. Prominent IgE binding was seen to a 46-kDa band of C. albicans (seven patients), C. utilis (five patients), and S. cerevisiae (one patient) and to corresponding weak bands of Cr. albidus and R. rubra (one patient). The possible cross-reactivity of the 46-kDa band was analyzed by IgE-IB inhibition and densitometry, revealing clear C. albicans inhibition of C. utilis (80%) and enolase (98%) (autoinhibition 100%). The strongest IgG responses were seen against S. cerevisiae and C. albicans. The responses were mainly against mannans of C. albicans and S. cerevisiae, suggesting that most of the exposure is to these yeasts. Yeasts with different types of exposure, from saprophytic growth on human mucous membranes to exposure by air and food, were shown to cross-react at the allergenic level. Atopic patients primarily sensitized by C. albicans and S. cerevisiae may develop allergic symptoms by exposure to other environmental yeasts due to cross-reacting IgE antibodies.

Nitrocellulose-RAST analysis of allergenic cross-reactivity of Candida albicans and Saccharomyces cerevisiae mannans.

Two chemically purified mannan preparations and one affinity purified mannan preparation of Candida albicans and Saccharomyces cerevisiae were analyzed for allergenic cross-reactivity. Simultaneous IgE binding in radioallergosorbent test (RAST) was studied with all preparations and the chemically purified mannans were also used for RAST inhibitions. The yeast mannans were purified with the Peat method, using repeated ethanol precipitations and Fehling's precipitation in alkaline conditions, and the Cetavlon method, using hexadecyltrimethylammonium bromide and ethanol precipitations. Affinity purification of the mannans was performed with concanavalin A lectin bound to a Sepharose column. Mannan from Pityrosporum ovale was purified with the Cetavlon method for analysis of simultaneous RAST reactivity. Simultaneous IgE binding to all the studied yeast mannans was generally seen in all the studied sera of patients suffering from atopic dermatitis. The strongest responses were seen against C. albicans mannan, especially the Cetavlon mannan. In the RAST inhibition studies IgE binding to S. cerevisiae mannan was completely inhibited by C. albicans mannan preparations, whereas reciprocal inhibition was not complete. These results indicate that in atopic dermatitis simultaneous IgE response to yeast polysaccharides occurs and that the major sensitizer is C. albicans and IgE antibodies against S. cerevisiae mannan are cross-reacting.

Immediate hypersensitivity to bakery, brewery and wine products in yeast-sensitive atopic dermatitis patients.

Ultrafiltered (> 1000 Da) samples of beer, aged red wine, young white wine, sparkling wine and extracts of fresh wheat bread and dried rye bread were analysed by skin-prick test (SPT), radioallergosorbent test (RAST) inhibition, sodium dodecylsulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting to find out if they contain Saccharomyces cerevisiae (S. cerevisiae, baker's yeast) allergens. Serum pool consisting of S. cerevisiae positive sera was used in the assays. The results were compared with freeze-dried reference S. cerevisiae and cereal antigens. The beer, bread, red wine and sparkling wine extracts elicited immediate reactions. However, no evident correlation with suspected symptoms was observed. White wine extract caused reactions in four out of six atopic dermatitis (AD) patients with symptoms, and in five out of seven symptom-free AD patients and in two of the 24 controls. In SDS-PAGE, protein bands were found in wheat and rye bread extracts and beer. In IgE immunoblotting, however, no staining was seen with the S. cerevisiae positive sera suggesting that they were of cereal origin. In white wine and champagne extracts a non-specific staining was seen in the region 20 kDa representing, e.g. lectin-like activity. No baker's yeast antigen could be detected in brewery and bakery products with IgE-immunoblotting even in the excessively concentrated extracts. The IgE mediated allergy to baker's yeast alone should thus not lead to denial of bakery, brewery and wine products.

Thermal and storage stability of Saccharomyces cerevisiae (baker's yeast) allergens.

The effect of storage and high temperatures on the stability of Saccharomyces cerevisiae allergens was studied by immunoblotting. Saccharomyces cerevisiae allergic serum pool and 125I- and galactosidase-labelled anti-IgE were used in the assays. Freeze-dried extracts were reconstituted with saline and with 50% glycerol and then stored at room (+20 degrees C) and refrigerator temperature (+6 degrees C) for different time periods. The stability was better in 50% glycerol at +6 degrees C than at room temperature without glycerol. However, after 1 month, two of the most important allergens of S. cerevisiae, the 48 and 32 kDa protein allergens, lost their IgE-binding capacity even in the extracts stored with 50% glycerol at +6 degrees C. The 45 kDa allergen was, on the other hand, quite stable after storage for 9 months at +6 degrees C. Although the beneficial effect of 50% glycerol was clear, storage at +6 degrees C, even with 50% glycerol should not exceed 1 month for S. cerevisiae extracts. Two commercially available S. cerevisiae extracts in solution with valid expiry dates were also analysed. They had only little allergenic potency, while a freeze-dried extract stored for 8 years showed good allergenic potency. Heating S. cerevisiae extracts resulted in precipitation, the precipitated fraction contained almost all the specific proteins as judged by electrophoresis and IgE detection. The supernatant fraction contained only a few allergens.

Gastrointestinal stability of baker's yeast allergens: an in vitro study.

An in vitro model was established to study the stability of baker's yeast (Saccharomyces cerevisiae) allergens in conditions simulating the gastrointestinal tract. The protocol consisted of 2 hr incubation under gastric conditions (pH 1.2, +37 degrees C and gastric enzymes) and 2 hr incubation under duodenal conditions (pH 6.8, +37 degrees C and duodenal enzymes). These were studied together and separately, as well as under pure acidic conditions without gastric enzymes. The yeast extracts contained equal amounts of allergen and were analyzed by IgE-immunoblotting. The acidic conditions had partly an enhancing and slightly degrading effect on the yeast allergens, whereas the gastric enzymes destroyed several allergens, including the important intermediate allergens of 31 and 45 kD. After treatment under both gastric and duodenal conditions most of the yeast allergens were destroyed, except mannan and a 10 kD protein component. The findings suggest that the allergen exposure caused by baker's yeast takes place mainly on the mucosal surfaces orally and oesophageally and through viable baker's yeast organisms that manage to pass the stomach and duodenum and possibly lead to intestinal growth of the organism. Patients with IgE production against the 10 kD allergen and mannan are, however, moderately exposed to allergens consisting of soluble antigenic material only.

Skin prick test reactions to brewer's yeast (Saccharomyces cerevisiae) in adult atopic dermatitis patients.

The sensitizing capacity of brewer's yeast (Saccharomyces cerevisiae) was studied with the skin prick test method in 449 subjects, including 226 atopic dermatitis (AD) patients, 50 patients with allergic rhinitis (AR) and/or asthma (A), and 173 nonatopic controls. A positive SPT reaction (> or = + +) was seen in 94% of patients with severe AD, in 76% with moderate AD, and in 25% with mild AD or no history of AD. Patients with AR and/or A and nonatopic controls displayed a positive reaction in only 8 and 2% of cases, respectively. There was also a parallel skin prick test reactivity with other yeasts including Pityrosporum ovale and Candida albicans, suggesting cross-reactivity. Parallel skin reactivity was observed also with molds and animal dander but not with pollen or house-dust mite. A significant correlation was also found between total serum IgE level and skin prick test (SPT) results with S. cerevisiae.

IgE-binding components of baker's yeast (Saccharomyces cerevisiae) recognized by immunoblotting analysis. Simultaneous IgE binding to mannan and 46-48 kD allergens of Saccharomyces cerevisiae and Candida albicans.

The Saccharomyces cerevisiae allergens were characterized by IgE-immunoblotting with serum samples of 83 patients; 63 represented patients with atopic dermatitis with previous positive skin prick test or RAST for S. cerevisiae, seven patients with AD but negative test results and 13 were non-atopic controls. Disrupted whole body extract of S. cerevisiae was used in the assays. From the patients tested 41 patients with atopic dermatitis appeared positive in IgE immunoblotting revealing 22 IgE stained bands. From these bands 10 represented intermediate allergens, and 12 minor allergens. The most frequent staining was obtained with the 48 kD band (39%). When the staining pattern of 45 kD and 48 kD bands and mannan was compared with Candida albicans allergens or purified baker's yeast enolase a simultaneous binding was seen with the 48 kD band of S. cerevisiae and the 46 kD band of C. albicans and enolase whereas the 45 kD band was neither associated with the 46 kD band of C. albicans nor purified enolase. High molecular weight staining was found in five samples. The staining pattern was associated with the mannose containing structures in parallel with C. albicans.