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Background: House dust mites are important allergen sources and some of these allergenic proteins may contain carbohydrate moieties, which are able to be isolated using lectins, as Concanavalin A (ConA). This study aimed to investigate allergenicity (IgE) and antigenicity (IgG1 and IgG4) of ConA-unbound and ConA-bound Dermatophagoides pteronyssinus (Dpt) crude extracts using sera of mite-allergic patients as well as inhibition capacity of antibody binding., Material and Methods: We obtained mannose-enriched and mannose-depleted fractions from Dpt by ConA affinity chromatography. Both ConA-bound and ConA-unbound fractions were evaluated by ELISA and Western Blotting for specific IgE, IgG1, and IgG4 reactivity with sera obtained from 95 mite-allergic patients (DP+) and 92 nonallergic (NA) subjects. Inhibition ELISA was used to assess cross-reactivity between Dpt extract and its fractions., Results: Among the DP+ patients, no difference was found between ConA-unbound and ConA-bound fractions regarding the levels of specific IgE, IgG1, and IgG4. Nonallergic subjects had the same levels of specific IgG1 to both ConA-unbound and ConA-bound fractions, although for specific IgG4, values were higher for ConA-bound. A positive correlation was found among specific IgE, IgG1, and IgG4 levels when Dpt was compared to ConA-unbound and ConA-bound fractions. Recognition of crude Dpt by IgE, IgG1, and IgG4 was highly inhibited by ConA-unbound and ConA-bound fractions. Western Blotting revealed a broad spectrum of bands ranging from 14 to 116 kDa recognized by specific IgE and IgG4. However, IgG1 reached higher frequency values on high molecular weight polypeptides., Conclusion: ConA-unbound and ConA-bound fractions derived from D. pteronyssinus crude extract revealed important components involved in the IgE recognition in allergic patients as well as IgG1 and/or IgG4 in allergic and healthy subjects., Competing Interests: The authors declare that there are no conflicts of interest regarding the publication of this paper.

Objective: The purpose of this study was to evaluate the effects of oropharyngeal colostrum administration in the incidence of late-onset clinical and proven sepsis and in concentrations of immunoglobulin A (IgA) in very-low-birth-weight (VLBW) infants., Methods: We conducted a double-blinded, randomized, placebo-controlled trial and assigned 113 VLBW infants to receive 0.2 mL of maternal colostrum or sterile water (placebo) via oropharyngeal route every 2 hours for 48 hours, beginning in the first 48 to 72 hours of life. Neonates of both groups were fed breast milk from the first 3 days of life until a volume of at least 100 mL · kg · day. IgA was measured in serum and urine before and after treatment. Clinical data during hospitalization were collected., Results: We found no statistically significant differences between colostrum and placebo groups in the incidence of late-onset clinical sepsis (odds ratio 0.7602; CI 95% 0.3-1.6) and proven sepsis (odds ratio 0.7028; CI 95% 0.3-1.6). The measurement of IgA was similar in serum before (P value 0.87) and after treatment (P value 0.26 day 4 and 0.77 day 18). No differences were also observed in IgA in urine before (P value 0.8) and after treatment (P value 0.73 day 4 and 0.52)., Conclusions: This study could not confirm the hypothesis that oropharyngeal administration of maternal colostrum to VLBW could reduce the incidence of late-onset sepsis and increase the levels of IgA. We believe that this finding can be justified by the practice of feeding VLBW infants exclusively with breast milk in the first days of life and reinforces the prior knowledge of the importance of early nutrition, especially, with human milk. It also suggests that oropharyngeal administration of colostrum should be reserved for neonates who cannot be fed in first few days of life.

Lolium multiflorum (Lm) grass pollen is the major cause of pollinosis in Southern Brazil. The objectives of this study were to investigate immunodominant components of Lm pollen allergens and the cross-reactivity of IgE with commercial grass pollen allergen extracts. Thirty-eight serum samples from patients with seasonal allergic rhinitis (SAR), 35 serum samples from patients with perennial allergic rhinitis (PAR) and 30 serum samples from non-atopic subjects were analyzed. Allergen sensitization was evaluated using skin prick test and serum IgE levels against Lm pollen extract were determined by ELISA. Inhibition ELISA and immunoblot were used to evaluate the cross-reactivity of IgE between allergens from Lm and commercial grass pollen extracts, including L. perenne (Lp), grass mix I (GI) and II (GII) extracts. IgE antibodies against Lm were detected in 100% of SAR patients and 8.6% of PAR patients. Inhibition ELISA demonstrated IgE cross-reactivity between homologous (Lm) and heterologous (Lp or GII) grass pollen extracts, but not for the GI extract. Fifteen IgE-binding Lm components were detected and immunoblot bands of 26, 28-30, and 32-35 kDa showed >90% recognition. Lm, Lp and GII extracts significantly inhibited IgE binding to the most immunodominant Lm components, particularly the 55 kDa band. The 26 kDa and 90-114 kDa bands presented the lowest amount of heterologous inhibition. We demonstrated that Lm extract contains both Lm-specific and cross-reactive IgE-binding components and therefore it is suitable for measuring quantitative IgE levels for diagnostic and therapeutic purposes in patients with pollinosis sensitized to Lm grass pollen rather than other phylogenetically related grass pollen extracts.

Unlabelled: The prevalence of allergic diseases such as asthma, rhinitis, allergic conjunctivitis and atopic dermatitis has increased in the last decades. The relationship between allergen exposure, atopic sensitization and development of allergic diseases is widely described in the literature., Aim: To evaluate measures for reducing allergen exposure as part of the treatment of allergic diseases., Methods: An analysis was made of previous studies on allergen exposure done with a similar methodology in the central region of Brazil; the study included homes, hotels, cinemas, cars, taxis, buses and scholar transportation., Results: High levels of Der p 1 and Der f 1 mite allergens were found in a large proportion of the sample in most of the environments included in those studies; there were higher levels of pet allergens in cars and school transportation vehicles., Conclusion: The diversity of allergen exposure demonstrates the need for education about allergic diseases for patients and their families, as well as measures of reducing allergens in homes. This should be part of a global strategy of the management of allergic diseases, given that individuals live in society, not only in their houses.

Strongyloidiasis, caused by the nematode Strongyloides stercoralis, is one of the major worldwide parasitic infections in humans. Breastfeeding may offer a potential protection against this infection. Feces, serum and milk samples were obtained from 90 lactating women from Clinical Hospital of Universidade Federal de Uberlândia, Brazil. The fecal samples were collected for parasitological diagnosis and the serum and milk samples were examined for specific S. stercoralis IgA and IgG antibodies using the indirect fluorescent antibody test (IFAT) and enzyme-linked immunosorbent assay (ELISA). Fecal examination showed that the rate of prevalence of S. stercoralis infection in the lactating women was 4.4%. IFAT manifested a 16.7% positivity rate for specific IgA antibody in serum and a 28.9% rate in milk samples; specific IgG was 41.1% in serum and 25.5% in milk samples. According to ELISA the positivity rate for specific IgA antibody was 21.1% in serum and 42.2% in milk samples; specific IgG was 40% in serum and 18.9% in milk samples. In serum samples, these immunological tests showed a concurrence of 91.1% and 94.4%, respectively, in detecting specific IgA and IgG antibodies. In milk samples, they showed a concurrence of 70% and 78.9%, respectively, in detecting specific IgA and IgG antibodies. There was a statistically significant difference between concordant and discordant results of immunological tests (P<0.0001). IFAT and ELISA highly concurred in their detection of specific S. stercoralis IgA and IgG antibodies in serum and in milk samples reconfirming prior studies that the serological method is a complement to the direct diagnosis of the parasite, and suggesting that immunological methods using milk samples can also be helpful. Furthermore, in endemic areas, infants may acquire antibodies to S. stercoralis from breast milk, possibly, contributing to the enhancement of specific mucosal immunity against this parasite.

Objective: This study aimed to evaluate the clinical efficacy and antibody response changes after specific immunotherapy (SIT) using Dermatophagoides pteronyssinus (Dpt) allergens with or without bacterial extracts in Brazilian mite-atopic patients., Methods: One-hundred patients with allergic rhinitis were selected for a randomized double-blind, placebo-controlled trial and distributed into 4 groups: Dpt (Dpt allergen extract), Dpt+MRB (Dpt allergen plus mixed respiratory bacterial extracts), MRB (MRB extract only) and placebo. Rhinitis symptom and medication scores; skin prick test (SPT) to Dpt extract; and serum immunoglobulin (Ig) E, IgG4, and IgG1 levels to Dpt, Der p 1, and Der p 2 allergens were evaluated before and after a year of treatment., Results: After 1 year, the SPT response was reduced in the Dpt group (P=.03), whereas IgE levels to Der p 2 decreased only in the Dpt (P = .048) and Dpt+MRB (P = .005) groups. IgG4 and IgG1 levels to Dpt and Der p 1 increased in the Dpt group (P < .05), whereas in the Dpt + MRB group the IgG1 level only increased to Dpt (P=.001) and the IgG4 only increased to Der p 1 (P=.049). IgE levels to Dpt decreased only in the MRB (P= .005) and Dpt + MRB (P= .001) groups. Rhinitis symptom and medication scores fell in all groups, including the placebo group (P<.001)., Conclusions: SIT using Dpt extract alone was effective in reducing SPT response and IgE levels to Der p 2 allergen, while bacterial extracts induced decreases in IgE levels to whole Dpt extract. However, only groups receiving Dpt allergen had higher levels of IgG1 and IgG4 to Dpt and Der p 1 after a year of treatment.

The aim of this study was to evaluate total IgG, IgG1, IgG4, and IgE antibody responses in human strongyloidiasis by enzyme-linked immunosorbent assay (ELISA) using Strongyloides ratti saline extract as heterologous antigen for a possible clinical utility of the assay. A total of 40 serum samples of patients who were shedding Strongyloides stercoralis larvae in feces (group I), 30 sera from patients with other intestinal parasites (group II), and 30 sera from subjects with negative results in three parasitological assays (group III) were analyzed to detect total IgG, IgG1, IgG4, and IgE to Strongyloides spp. by ELISA and expressed in ELISA index. Levels of total IgG anti-Strongyloides spp. were significantly higher in patients of group I than in groups II (p=0.0005) and III (p<0.0001). Levels of specific IgG1, IgG4, and IgE of group I were also significantly higher than in groups II and III, respectively. There was a significant positive correlation between specific IgE and IgG4 (r=0.6524; p=0.0084) and IgG1 and IgG4 (r=0.5398; p=0.0171). It can be concluded that the detection of specific IgE, IgG1, and IgG4 subclasses rather than total IgG antibodies to Strongyloides spp. using the S. ratti antigen showed to be an additional tool for improving the serodiagnosis of human strongyloidiasis.

Unlabelled: Mite allergens are involved in airway sensitization and allergic diseases. We evaluated the exposure to house dust-mite (Der p 1 and Der f 1) and pet (Fel d 1 and Can f 1) allergens in hotels in Uberlândia, Midwestern Brazil. A total of 140 dust samples were collected from bedding (n = 98) and carpet (n = 42) of bedrooms in 20 hotels enrolled for this study. Geometric mean (GM) levels of Der f 1 (11.30 microg/g of dust; 95% CI: 8.34-15.30 microg/g) were significantly higher than Der p 1 (0.15 microg/g of dust; 95% CI: 0.13-0.18 microg/g) in bedding dust samples (P < 0.001), regardless of the hotel classes. Der f 1 levels were significantly higher in bedding (11.30 microg/g of dust; 95% CI: 8.34-15.30 microg/g) than carpet (6.32 microg/g of dust; 95% CI: 4.31-9.26 microg/g) dust samples (P < 0.05). High levels of Der f 1 (>10 microg/g of dust) were found in 58%, 76%, and 69% of dust samples from Simple, Economical, and Tourist/Superior hotels, respectively, while GM levels of Fel d 1 (0.11 microg/g of dust; 95% CI: 0.09-0.14 microg/g) and Can f 1 (0.30 microg/g of dust; 95% CI: 0.20-0.44 microg/g) were relatively low. These results indicate that Der f 1 is the predominant allergen in hotels in Uberlândia, especially in bedding dust samples, regardless of the hotel classes and could represent an important risk factor for exacerbation of allergic symptoms in previously mite-sensitized guests., Practical Implications: Mites and pets are important sources of indoor allergens. Most people spend the greatest part of their time indoors. Hotels can constitute an important allergen reservoir of the indoor environment and could represent an important risk for exacerbation of allergic symptoms in previously sensitized guests. Thus, hotels should also be included for planning indoor allergen avoidance as part of a global management strategy, especially in patients with respiratory allergy.

The prevalence and clinical relevance of IgM and IgA RF detected by ELISA were studied in 91 patients with juvenile rheumatoid arthritis (JRA) and 45 healthy children. IgM and IgA RF were detected, respectively, in 33 and 44% of the patients, compared to 6.7 and 15.6% of the healthy children (p = 0.001 and 0.0006, respectively). The frequency of IgM RF was significantly higher in patients with polyarticular (52%) as compared to systemic onset JRA (21%; p = 0.04). Five out of ninety-one patients and none of the control group were IgM RF positive by the latex test. High levels of IgM RF were detected more frequently in patients with active disease (p = 0.01) and positive latex agglutination test (p < 0.001) and had a marginally significant association with severe radiological deformities (p = 0.05). The presence of IgA RF was associated with active disease in polyarticular onset JRA children (p = 0.04). In conclusion, high levels of IgM RF and the detection of IgA RF can be useful in assessing clinical activity in a subset of patients with JRA.

Objective: To evaluate allergens among patients with allergic respiratory disease attended at the Allergy Clinic of the University Hospital-Federal University of Uberlândia., Methods: A retrospective study was performed using medical records. Patients were included if their ISAAC questionnaires were correctly filled out and their skin prick tests were positive to at least one of the allergens from Dermatophagoides pteronyssinus (Der p), Dermatophagoides farinae (Der f), Blomia tropicalis (Blo t), Canis familiaris (Can f), Felis domesticus (Fel d), Blattella germanica (Bla g) and Alternaria alternata., Results: Two-hundred and twelve medical records fulfilled the inclusion criteria. Allergic rhinitis was the main clinical diagnosis (32%), followed by concomitant manifestation of asthma and rhinitis (29.7%), and asthma, rhinitis and atopic dermatitis (9.4%). Asthma alone was found only in 1.9% of patients. The total sensitization observed was 73.5%, of which 61.7%, 59.9%, 54.7%, 45.7%, 38.2%, 33.3%, 9.9% were sensitized to Der p, Der f, Blo t, Bla g, Can f, Fel d and Alternaria, respectively. No significant difference was found between allergic disease types and source of allergen sensitization., Conclusion: The highest sensitization in allergic patients under study was to dust mites, especially Der p and Der f. It is noteworthy that the number of patients sensitized to cockroach extract was uncommonly high when compared to previous studies.

Patients with grass pollen allergy, commonly called pollinosis, often present reactivity to pollen allergens from a number of grass species due to cross-reactivity of IgE antibodies to pollen proteins present in pollen grasses. In this context, Italian rye grass (Lolium multiflorum) pollen of the Poaceae family cultivated in Southern Brazil has been considered a major sensitizing agent in patients with pollinosis. In this region, Italian rye grass is capable of producing a great amount of pollen. In addition to L. multiflorum, other Poaceae grasses are naturally grown as weed in Southern Brazil, but with no clinical relevance. Pollen extracts derived from homologous or heterologous grasses are often used for both diagnosis and treatment of seasonal allergy. However, no standardized L. multiflorum pollen extract is commercially available in Brazil and mixed grass extracts are commonly used for diagnosis and immunotherapy of grass pollen allergy. Further studies are required to better characterize the cross-reactivity between L. multiflorum and other grass pollen allergens for improving the diagnosis and immunotherapy to L. multiflorum pollen allergy.

Background: Lolium multiflorum (Lm) pollen allergens are the major causative agents for rhinoconjunctivitis in Southern Brazil. There have been no studies about the sensitization and allergenic cross-reactivity between Lm and other grass pollens. We evaluated the sensitization of Brazilian pollinosis patients to Lm pollen allergens through skin prick test (SPT) and immunoassays (ELISA and immunoblot)., Methods: Serum samples from 60 patients with pollinosis and positive SPT to grass pollen extracts (Lm+ group), 30 patients with negative SPT to grass pollen, but positive SPT to mite extracts (Lm- group), and 30 nonatopic subjects (NA group) were tested by SPT, ELISA, and immunoblot using Lm extract. Inhibition immunoassays with Lolium perenne (Lp), mixed grass (Gmix) and Lm extracts were also performed., Results: A high concordance was found between the Gmix and Lm extracts in SPT. Positivity rates in SPT were also highly concordant with IgE-ELISA results. The assay was able to detect Lm-specific IgE in >95% of Lm+ patients. A significant self- and cross-inhibition was observed in IgE-ELISA, reflecting a high cross-reactivity between the grass pollen allergens. Immunoblot revealed 13 IgE-binding Lm fractions, from which the bands 28-30 kDa and 31-34 kDa were recognized by >90% of Lm+ patients., Conclusion: Lm-specific IgE antibodies are highly cross-reactive with pollen proteins from other grass species. The results indicate that Lm extracts could be used in both SPT and ELISA for a more specific evaluation of IgE responses to Lm grass pollen in Brazilian pollinosis patients.

Indoor allergens are major causative agents in allergic disease development. Besides homes, public transport vehicles have been considered important mite and pet allergen reservoirs. Our recent studies on allergen exposure in automobiles showed that different allergen levels are found in private cars versus taxis. We quantified group 1 Dermatophagoides spp. (Der 1), Felis domesticus (Fel d 1), and Canis familiaris (Can f 1) allergen levels by ELISA in dust samples from 60 taxi and 60 private car upholstered seats. Mean levels of Der 1 and Fel d 1 were significantly higher in taxis than private cars. A significantly higher percentage of taxis (42%) harboring sensitizing levels of Der 1 compared to private cars (5%) was also found. In spite of the low mean Fel d 1 levels, comparison of the percentage of vehicles with moderate Fel d 1 levels showed a significant difference between taxis and private cars (43% vs. 20%). On the other hand, mean Can f 1 levels were significantly higher in private cars compared to taxis concomitant with a significantly higher percentage of private cars containing moderate Can f 1 levels than taxis (53% vs. 28%). We conclude that upholstered seats from Brazilian taxis but not private cars constitute an important mite allergen reservoir. Thus, additional effective measures for the reduction of allergen exposure in vehicles within the global allergen avoidance strategy should also be routinely accomplished to minimize the induction of sensitization and symptoms in allergic patients.

Several studies have shown that the presence of IgE antibodies to house dust mites (HDM), particularly Dermatophagoides pteronyssinus (Dpt), is an important risk factor for asthma. Allergen immunotherapy is indicated for patients with IgE antibodies to clinically relevant allergens. The aims of this study were to analyze the levels of specific serum IgE to Der p 1 and Der p 2 allergens in mite-sensitized atopic patients and to compare them with both in vivo (skin prick test) and in vitro (IgE-ELISA) sensitizations to Dpt crude extract. Forty-seven atopic patients with allergic rhinitis with or without intermittent or persistent mild asthma and positive skin prick test (SPT) to Dpt total extract were studied. Thirty age-matched healthy subjects with negative SPT to HDM were included as controls. Levels of total IgE and Dpt-, Der p 1- and Der p 2-specific IgE were measured by ELISAs in SPT-positive atopic patients and SPT-negative control subjects. Among 47 symptomatic atopic patients, 27 (57.4%) were double positive IgE to Der p 1 and Der p 2 allergens, 3 (6.4%) were single positive IgE to Der p 1, 4 (8.5%) were single positive IgE to Der p 2, and 13 (27.6%) were double negative IgE to both allergens. There was a significant correlation between Der p 1- and Der p 2-specific IgE levels, but not between Der p 1- or Der p 2-IgE levels and SPT results. The double negative IgE patients had the smallest skin test reactions although they showed high mean levels of total serum IgE. Therefore, the knowledge of specific IgE levels to Der p 1 and Der p 2 major allergens might support physicians for indication or follow-up in mite-sensitized patients under allergen-specific immunotherapy. These approaches might be important for obtaining improved safety and efficacy of the current clinical practice of allergen immunotherapy.

Background: The role of mite and pet allergens in the development of allergic diseases has been recognized for many years., Objective: To determine mite (Dermatophagoides pteronyssinus [Der p 1] and Dermatophagoidesfarinae [Der f 1]), cat (Felis domesticus [Fel d 1]), and dog (Canis familiaris [Can f 1]) allergen levels in Brazilian private cars., Methods: Mite, cat, and dog allergens were measured in dust samples collected from 60 upholstered seats of private vehicles using enzyme-linked immunosorbent assays., Results: Mean levels of Der p 1 (0.24 microg/g of dust; range, 0.06-2.05 microg/g of dust) and Der f 1 (0.29 microg/g of dust; range, 0.06-2.07 microg/g of dust) were extremely low in most dust samples analyzed. In contrast, sensitizing mean levels of Can f 1 (1.51 microg/g of dust; range, 0.14-30.96 microg/g of dust) and Fel d 1 (0.43 microg/g of dust; range, 0.02-5.75 microg/g of dust) were observed in 32 (53%) and 12 (20%) samples, respectively. Mean Can f 1 levels were significantly higher in cars whose owners kept dogs at home (3.27 microg/g of dust) than in those without pets (0.57 microg/g of dust; P = .008). There were no significant differences in allergen levels regarding the age of the vehicle or the number of users and whether the owners transport pets inside the vehicles., Conclusions: Private cars constitute an important pet, but not mite, allergen reservoir for continuous contamination of the indoor environment. Pet allergens may be present even in cars whose owners do not have pets. Effective measures to reduce allergen exposure in cars should be taken routinely, especially for pet-allergic patients.

Background: Mites and pets are important sources of indoor allergens., Objectives: To determine Dermatophagoides pteronyssinus (Der p 1), Dermatophagoides farinae (Der f 1), and Felis domesticus (Fel d 1) allergen levels in buses and taxis and to evaluate the predominant allergen in each vehicle type., Methods: Mite and cat allergens were measured using enzyme-linked immunosorbent assay in dust samples collected from upholstered seats in 60 natural-ventilation buses (NVBs), 60 artificial-ventilation buses (AVBs), and 60 taxis. Thirty dust samples from AVB air-conditioning filters were also included., Results: Levels of Der p 1 and Der f 1 were significantly higher in AVBs than in NVBs, whereas Fel d 1 levels were not significantly different between bus types. No significant differences were found in mite allergen levels in various sites in both types of buses, whereas Fel d 1 levels were significantly higher in rear and middle seats than in front seats in NVBs. Mite and cat allergen levels in taxis were significantly higher in passenger's rear seats than in driver's seats. A high proportion of dust samples from the vehicles, especially AVBs (82% for Der p 1 and 58% for Der f 1) had sensitizing levels of mite allergens, whereas more than 60% of samples from all vehicles had sensitizing levels of Fel d 1 allergen. In AVBs, samples from seats showed significantly higher levels of mite and cat allergens than those from air-conditioning filters., Conclusions: Public transport vehicles constitute an important allergen reservoir for continuous contamination of the indoor environment.

IgE antibody response in human strongyloidiasis was evaluated by enzyme-linked immunosorbent assay (ELISA) and immunoblotting (IB) using Strongyloides ratti saline extract as heterologous antigen. A total of 50 serum samples of patients who were shedding S. stercoralis larvae in feces (group I, copropositive), 38 of patients with other intestinal parasites (group II), and 38 of subjects with negative results in three parasitologic assays (group III, copronegative) were analyzed. Levels of IgE anti-Strongyloides expressed in ELISA Index (EI) were significantly higher in patients of group I (1.32) than in group II (0.51) and group III (0.81), with positivity rates of 54%, 0%, and 10.5%, respectively. Fifteen S. ratti antigenic components were recognized in IB-IgE by sera of group I, with frequency ranging from 8% to 46%. In group II, only two antigenic bands (101, 81 kDa) were detected in a frequency of 10% and no reactivity was found in group III. Sera with EI values > 1.5 recognized five from 13 specific antigenic bands (70, 63, 61, 44, 7 kDa). It can be concluded that these five antigenic components recognized by IB-IgE using S. ratti antigen might be employed as an additional tool for improving the immunodiagnosis in human strongyloidiasis.

Mite allergen exposure has been widely related to sensitization and development of allergic diseases. This study intended to evaluate the degree of allergen exposure in Uberaba, Brazil, through the measurements of Der f 1 and Der p 1 allergen levels associated with the acarologic analysis in house dust samples. A total of 240 dust samples were collected from 60 houses through vacuuming sofas and bedding, during the months of March and July 2000. Indoor temperature and relative humidity were also measured. Mites were counted and identified under light microscopy and allergen levels were measured by two-site monoclonal antibody ELISAs. The major mite family was Pyroglyphidae (39.4%), having D. pteronyssinus as the most frequent species (15.6%), followed by D. farinae (12.3%) and E. maynei (7.9%). The family Glycyphagidae was less commonly found (4.8%), with Blomia tropicalis (4.4%) as its majoritary member. The highest levels of Der f 1 and Der p 1 allergens were found in bedding samples in March (31.7 and 0.9 microg/g of dust, respectively), with Der f 1 levels significantly higher than Der p 1 (p < 0.0001). There was a significant positive correlation between the mite number and allergen levels. These results indicate that Dermatophagoides sp are the most frequent mites in our region followed by E. maynei. Therefore, the knowledge of the local mite fauna would improve the means of investigating the association between allergen exposure and sensitization, allowing the addition of new mite extracts in diagnostic tests.

Purpose: To determine the levels of IgA, IgE, IgG and subclasses (IgG1, IgG4) antibodies specific to C. albicans in serum and vaginal washes from women with or without vulvovaginal candidiasis in order to evaluate the role of these antibodies in the immunopathogenesis of the disease., Methods: Thirty women with clinical symptoms of vulvovaginal candidiasis (15 positive vaginal culture to C. albicans, 11 negative culture and 4 positive culture to non-C. albicans) and 12 asymptomatic control women were selected. Serum and vaginal wash samples were obtained for the detection of anti-C. albicans antibodies by ELISA., Results: Symptomatic patients with positive culture showed significantly higher levels of specific IgA in vaginal washes and lower in serum than those with negative culture. Specific serum IgE levels were very low compared to vaginal IgE. High levels of total specific IgG were found in serum and vaginal washes in both groups, regardless the fungal presence or absence. Specific IgG1 and IgG4 levels were significantly higher only in vaginal washes from symptomatic patients with positive culture, with a slightly higher IgG1/IgG4 ratio, indicating that the IgG1 antibody response may be predominantly involved in the fungal clearance., Conclusion: Our results indicate a pronounced antibody response of IgA, IgG1 and IgG4 to C. albicans in vaginal washes in symptomatic patients with positive culture, suggesting a important role of these antibodies in the local immune response triggered by the presence of the fungus.

Strongyloides ratti larval extract was used for the standardization of ELISA to detect genus-specific IgE in human strongyloidiasis. Forty serum samples from monoinfected patients shedding S. stercoralis larvae (Group I), 40 from patients with other intestinal parasites (Group II), and 40 from copronegative healthy subjects (Group III) were analyzed. Genus-specific IgE levels (ELISA Index: EI) were significantly higher in the group I (EI = 1.43) than groups II (EI = 0.70) and III (EI = 0.71), showing positivity rates of 55%, 2.5% and 0%, respectively. Similarly, sera from copropositive patients had significantly higher levels of total IgE (866 IU/mL) as compared to those from group II (302 IU/mL) and III (143 IU/mL). A significant positive correlation was found between levels of Strongyloides specific-IgE and total IgE in sera from patients with strongyloidiasis. In conclusion, S. ratti heterologous extract showed to be a useful tool for detecting genus-specific IgE by ELISA, contributing for a better characterization of the immune response profile in human strongyloidiasis.

Objectives: To determine the presence of immunoglobulin E-rheumatoid factor in patients with juvenile rheumatoid arthritis and to correlate it with clinical and laboratory parameters., Methods: A multicenter prospective study was carried out from January 1993 to January 1999 with the enrollment of 3 centers of pediatric rheumatology. Ninety-one children with juvenile rheumatoid arthritis diagnosed according to the American College of Rheumatology criteria were studied: 38 (42%) with systemic, 28 (31%) with pauciarticular, and 25 (27%) with polyarticular onset. Ages ranged from 2.1 years to 22.6 years (mean 10.5 +/- 4.7), with 59 (65%) girls. The control group consisted of 45 healthy children. The detection of immunoglobulin E-rheumatoid factor was carried out utilizing an enzyme-linked immunosorbent assay. Associations of immunoglobulin E-rheumatoid factor with immunoglobulin M-rheumatoid factor (latex agglutination test), total serum immunoglobulin E, erythrocyte sedimentation rate, antinuclear antibody, and functional and radiological classes III or IV were analyzed., Results: Positive immunoglobulin E-rheumatoid factor was found in 15 (16.5%) of the 91 children with juvenile rheumatoid arthritis: 7 (18.5%) with systemic, 5 (18%) with pauciarticular, and 3 (12%) with polyarticular onset. A significant correlation was observed between immunoglobulin E-rheumatoid factor and total serum immunoglobulin E in the juvenile rheumatoid arthritis patients. No correlation was found between immunoglobulin E-rheumatoid factor and positive latex agglutination slide test, erythrocyte sedimentation rate, antinuclear antibody, or the functional and radiological classes III or IV in any disease onset group. In 4 out of 45 control children (8.9%), immunoglobulin E-rheumatoid factor was positive but with no correlation with total serum immunoglobulin E levels., Conclusions: Immunoglobulin E-rheumatoid factor could be detected in 16.5% of juvenile rheumatoid arthritis patients, particularly in those with high levels of total serum immunoglobulin E, and immunoglobulin E-rheumatoid factor appears not to be associated with disease activity or severity.

Background: Epidemiologic studies have shown that the presence of IgE antibodies to house dust mite and other indoor allergens is an important risk factor for asthma., Objective: The aim of this study was to develop a reverse ELISA (rELISA) for measuring specific IgE to Der p 2, a major Dermatophagoides pteronyssinus (Dpt) allergen, as a potential tool for followup of allergen immunotherapy., Methods: Recombinant Der p 2 allergen or a monoclonal antibody to Der p 2 was used to coat plates in conventional ELISA (cELISA) and rELISA, respectively. Sera from 48 asthmatic patients with positive skin prick test (SPT+) to D. pteronyssinus extract were analyzed for total IgE and specific IgE to Der p 2, and the results were compared with a group of 41 SPT asthmatic and 30 SPT- control subjects., Results: The sensitivity of the two assays for Der p 2-specific IgE was 3.9 EU/mL and their specificities were confirmed by inhibition tests, in a dose-dependent manner. There was a significant positive correlation between cELISA and rELISA (r = 0.74; P < 0.0001). However, rELISA was more sensitive than was cELISA, regarding both the positive sera percentage (70.8% vs 52.1%) and the Der p 2-specific IgE levels (28.4 vs 4.5 EU/mL) in SPT+ asthmatic patients., Conclusions: rELISA has shown to be a sensitive and alternative method for measuring Der p 2-specific IgE without using radioactive techniques. Detection of specific IgE to major allergens and relevant peptides, and identification of B cell epitopes in allergens will provide valuable information for the design of allergen analogs and peptides for immunotherapy.

Background: The role of mite allergen exposure in sensitization and development of asthma has been widely recognized. Previous studies have shown that Dermatophagoides pteronyssinus and Blomia tropicalis were the most prevalent house dust mites in Brazil, while D. farinae was rarely found. The aim of this study was to measure Der f 1 and Der p 1 allergen levels in Brazilian asthmatics' and controls' homes., Methods: Sixty-four houses (32 asthmatic, 32 control) were visited for dust sampling from five sites. Der f 1 and Der p 1 levels were measured by two-site monoclonal-antibody-based ELISAs., Results: The highest levels of Der f 1 and Der p 1 allergens were found in bedding samples from both asthmatics' and controls' homes. However, the geometric mean of Der f 1 levels (15.8 microgram/g of dust) was significantly higher than for Der p 1 (8.2 microgram/g of dust) in these samples. In addition, allergen levels >/=10 microgram/g of dust were found in 60-80% of the samples for Der f 1 and about 50% for Der p 1., Conclusions: These results indicate that high levels of Der f 1 allergen are present in both asthmatics' and controls' homes, in contrast to previously reported data. Therefore, studies on exposure to mites should be performed in different cities, seasons and times, since the mite fauna might be subject to variations. Knowledge of the mite fauna will certainly improve the means of investigating the association between allergen exposure and sensitization, allowing to establish the inclusion of new mite extracts in inhalant skin test sets, and even to detect monosensitized patients with respiratory allergy., (Copyright 2000 S. Karger AG, Basel.)