ABSTRACT ABO, H, secretor and Lewis histo-blood system genes control the expression of part of the carbohydrate repertoire present in areas of the body occupied by microorganisms. These carbohydrates, besides having great structural diversity, act as potential receptors for pathogenic and non-pathogenic microorganisms influencing susceptibility and resistance to infection and illness. Despite the knowledge of some structural variability of these carbohydrate antigens and their polymorphic levels of expression in tissue and exocrine secretions, little is known about their biological importance and potential applications in medicine. This review highlights the structural diversity, the biological importance and potential applications of ABO, H, Lewis and secretor histo-blood carbohydrates.

Abstract: INTRODUCTION Toxoplasmosis during pregnancy can be severe; thus, it is essential to diagnose the disease via serological tests. METHODS An enzyme-linked immunosorbent assay (ELISA) was used to investigate anti-Toxoplasma gondii immunoglobulin A (IgA), M (IgM) and G (IgG) antibodies in 62 high-risk pregnant women. RESULTS Forty-three (69.4%) women were positive for IgA, 31 (50%) for IgG, and 57 (91.9%) for IgM; 4 (6,5%) were positive for IgA but negative for IgM; 10 (16.1%) were negative for IgA and IgM but positive for IgG. CONCLUSIONS Testing for these antibodies can help diagnose infection in pregnant women, thereby contributing to clinical management.

OBJECTIVE:Allergic rhinitis is a disease that affects the upper airways and causes inflammation of the nasal mucosa and it is mediated by IgE antibodies produced after sensitization to environmental allergens. Previous reports have indicated that this disease affects males more often than females. The objective of this study was to verify whether total IgE plasma levels vary between genders in patients suffering from allergic rhinitis.METHODS:A total of 171 adult patients suffering from allergic rhinitis (55 males and 116 females) were enrolled. Total IgE plasma levels were determined using commercial kits, with 140 IU/mL considered as a reference value. The mean total IgE plasma levels were compared according to gender and age.RESULTS:The mean age of the overall patient group with allergic rhinitis was 38.4±19.0 years and a significant difference in age was observed between genders (males: 32.2±17.8 years; females: 41.4±18.9 years; p= 0.0027). Additionally, the mean total IgE plasma levels were higher in males (413.0±143.0 IU/mL) than in females (147.9±98.0 IU/mL) (p<0.0001). These differences persisted even when males and females were stratified by age (up to or older than 20 years of age).CONCLUSIONS:In conclusion, total IgE plasma levels are higher in young adult males than in females suffering from allergic rhinitis. Evaluating total IgE plasma levels can be useful to identify patients at risk of allergic rhinitis in areas with low industrial pollution.

OBJECTIVE: The aim of this study was to verify if ABO phenotypes are associated with allergic rhinitis. METHODS: 168 patients with allergic rhinitis and 168 control individuals from the same geographical region and paired by gender and age were enrolled in the study. ABO phenotypes were identified in red blood cells using the hemagglutination technique. The Fisher exact and chi-squared tests were employed to compare proportions. Statistical significance was set for an alpha error of 5% (p-value < 0.05). RESULTS: The overall differences in the frequencies of the ABO phenotypes of patients and controls were marginal (χ2: 7.569; degrees of freedom (DF): 3; p-value = 0.055) however the O blood group was associated with allergic rhinitis (χ2: 5.764; DF: 1; p-value = 0.016; OR: 1.735; CI 95%: 1.127-2.673). The differences in the frequencies of the O phenotype in patients and controls were statistically different for men (χ2: 8.520; DF: 1; p-value = 0.003) but not for women (χ2: 0.6375; DF: 1; p-value = 0.4246). The A phenotype was associated with protection (OR: 0.4385; CI 95%: 0.2043-0.9415; p-value = 0.049) and the O phenotype was associated with susceptibility (OR = 2.789; CI 95%: 1.385-5.616; p-value = 0.005) to allergic rhinitis only for men. CONCLUSION: The O blood group phenotype is associated with allergic rhinitis in male but not in female patients.

CONTEXTO E OBJETIVOS: A toxoplasmose, quando transmitida durante a gestação, pode causar graves sequelas em fetos e neonatos. Anticorpos maternos podem ser indicadores de risco ou de imunidade. O objetivo foi avaliar a positividade dos anticorpos das classes imunoglobulina M (IgM) e imunoglobulina G (IgG) anti-Toxoplasma gondii (anti-T. gondii), bem como a avidez de IgG em gestantes e seus neonatos. TIPO DE ESTUDO E LOCAL: Estudo transversal em ambulatório de gestação de alto risco. MÉTODOS: Anticorpos anti-T. gondii foram avaliados em amostras de soro de gestantes (n = 87) e seus respectivos neonatos (n = 87) com o uso dos métodos imunofluorescência indireta (IFI) (IgM e IgG), ensaio imunoenzimático (ELISA) (IgG) e avidez. RESULTADOS: Anticorpos anti-T. gondii foram identificados em 64,4% das amostras de soro das mães e seus bebês (56/87). Com exceção de duas amostras de soro materno (2,3%), todas as demais foram negativas anticorpos IgM anti-T. gondii determinado pela IFI. Os resultados mostraram que 92,9% das gestantes tinham índices elevados de avidez de IgG (> 30%) e 4 amostras apresentaram índices de avidez entre 16-30%. Duas gestantes no terceiro trimestre da gravidez eram positivas IgM anti-T. gondii; seus bebês apresentaram índices de avidez entre 16 e 30%. Os índices de avidez dos soros dos outros 83 recém-nascidos foram semelhantes àqueles encontrados nas amostras maternas. CONCLUSÕES: Os resultados mostraram que 2% das gestantes estavam sob risco de transmissão de T. gondii durante o período gestacional. Estes dados parecem refletir a real situação da toxoplasmose gestacional na região noroeste do Estado de São Paulo.

CONTEXT AND OBJECTIVE: Toxoplasmosis transmission during pregnancy can cause severe sequelae in fetuses and newborns. Maternal antibodies may be indicators of risk or immunity. The aim here was to evaluate seropositivity for anti-Toxoplasma gondii (anti-T. gondii) immunoglobulin M (IgM) and immunoglobulin G (IgG) antibodies and IgG avidity in pregnant women and their newborn infants. DESIGN AND SETTING: Cross-sectional study in a high-risk pregnancy outpatient clinic. METHODS: Serum samples from pregnant women (n = 87) and their respective newborns (n = 87) were evaluated for anti-T. gondii antibodies using indirect immunofluorescence (IIF) (IgM and IgG), enzyme-linked immunosorbent assay (ELISA) (IgG) and an avidity test. RESULTS: Anti-T. gondii antibodies were identified in 64.4% of the serum samples from the mothers and their infants (56/87). Except for two maternal serum samples (2.3%), all others were negative for anti-T. gondii IgM antibodies, using IIF. The results showed that 92.9% of the pregnant women had high IgG avidity indexes (> 30%) and four samples had avidity indexes between 16 and 30%. Two women in the third trimester of pregnancy were positive for anti-T. gondii IgM antibodies; their babies had avidity indexes between 16 and 30%. The avidity indexes of serum from the other 83 newborns were similar to the results from their mothers. CONCLUSIONS: The results showed that 2% of the pregnant women were at risk of T. gondii transmission during the gestational period. These data seem to reflect the real situation of gestational toxoplasmosis in the northwestern region of the state of São Paulo.

OBJECTIVE: Adenosine deaminase acts on adenosine and deoxyadenosine metabolism and modulates the immune response. The adenosine deaminase G22A polymorphism (20q.11.33) influences the level of adenosine deaminase enzyme expression, which seems to play a key role in maintaining pregnancy. The adenosine deaminase 2 phenotype has been associated with a protective effect against recurrent spontaneous abortions in European Caucasian women. The aim of this study was to investigate whether the G22A polymorphism of the adenosine deaminase gene is associated with recurrent spontaneous abortions in Brazilian women. METHODS: A total of 311 women were recruited to form two groups: G1, with a history of recurrent spontaneous abortions (N = 129), and G2, without a history of abortions (N = 182). Genomic DNA was extracted from peripheral blood with a commercial kit and PCR-RFLP analysis was used to identify the G22A genetic polymorphism. Fisher's exact test and odds ratio values were used to compare the proportions of adenosine deaminase genotypes and alleles between women with and without a history of recurrent spontaneous abortion (p<0.05). The differences between mean values for categorical data were calculated using unpaired t tests. The Hardy-Weinberg equilibrium was assessed with a chi-square test. RESULTS: Statistically significant differences were identified for the frequencies of adenosine deaminase genotypes and alleles between the G1 and G2 groups when adjusted for maternal age. CONCLUSIONS:The results suggest that the adenosine deaminase *2 allele is associated with a low risk for recurrent spontaneous abortions, but this association is dependent on older age.

Infectious and parasitic diseases affecting women during their reproductive age may result in vertical transmission. The aim of this study was to determine the seroprevalence for TORSCH among pregnant women receiving care at a university hospital. Records of 574 pregnant women who received medical attention from January 2006 to December 2007 were assessed. The mean age was 27.2 ± 6.5 years ranging from 13 to 44. The results of the immunodiagnostic tests were: 62.0% (345/556) for IgG and 3.4% (19/556) for IgM anti-T. gondii; 93.1% (433/465) for IgG and 0.6% (3/465) for IgM anti-rubella; 0.9% (5/561) for VDRL; 1.8% (10/554) for HBsAg; 0.7% (4/545) for anti-HCV and 2.1% (11/531) for HIV. In conclusion, the results of immunodiagnostic tests for the TORSCH panel among pregnant women attending a perinatal service of a university hospital are in agreement with those reported by previous studies and by governmental sources.

Estudos prévios demonstraram associação entre o sistema Lewis e a doença arterial coronariana (DAC) a partir da observação de que o fenótipo eritrocitário Le(a-b-) era prevalente em pacientes e propuseram que esse fenótipo representava um novo marcador de risco para essa doença. Esse estudo teve como objetivo verificar a prevalência desse marcador em pacientes brasileiros com indicação de realizar cineangiocoronariografia. A fenotipagem do sistema Lewis foi realizada pelo método gel centrifugação, e a genotipagem do loco LE foi feita pelo método PCR-RFLP. Cento e oitenta e três pacientes (114 masculinos e 69 femininos, com média de idade igual a 59,1 anos (DP ± 12,37; mediana 60) foram selecionados. Cento e vinte e um (66,1%) pacientes apresentaram obstrução coronariana de qualquer grau, sendo essa característica duas vezes mais elevada no sexo masculino do que no feminino (p=0,07). As freqüências dos fenótipos eritrocitários Lewis foram semelhantes em ambos os grupos de pacientes e o fenótipo Le(a-b-) mostrou-se não estar associado à presença de obstrução coronariana (p=0,36). Elevados índices de discrepância fenótipo-genótipo foram observados entre os pacientes Le(a-b-), com base na genotipagem das mutações T59G (86,7%) e T1067A (90,0%). As freqüências dos alelos T e G (posição 59) e T e A (posição 1067) não mostraram diferenças estatisticamente significantes entre os pacientes com e sem obstrução coronariana (p = 0,52 e p = 0,44, respectivamente). Esses resultados demonstram que o sistema Lewis não está associado à presença de obstrução coronariana e não suportam a proposição de que o fenótipo eritrocitário Le(a-b-) representa um marcador de risco para essa doença na casuística brasileira.

Previous studies have shown an association between the Lewis blood group system and coronary artery disease (CAD) from the observation that the Le(a-b-) red blood cell phenotype was prevalent among these patients and thus proposed this red blood cell phenotype as a new genetic marker for the disease. The aim of this study was to verify the prevalence of this genetic marker among Brazilian patients who had undergone coronary arteriography. Phenotyping of the Lewis system was carried out using gel centrifugation and genotyping of the LE locus was made using PCR-RFLP. One hundred and eighty-three patients, 114 male and 69 female, with an average age of 59.1 years (SD ± 12.37; median 60), were enrolled. One hundred and twenty-one (66.1%) patients presented some degree of coronary obstruction, which was two times more frequent in men compared to women (p=0.07). The frequencies of the Lewis red blood cell phenotypes were similar between patients with and without coronary obstruction and the Le(a-b-) was not associated to the presence of coronary obstructions (p=0.36). A high level of discrepancies between phenotype and genotype were observed in Lewis negative patients based on genotyping of the T59G (86.7%) and T1067A (90.0%) SNPs. The frequencies of T and G alleles (position 59) and T and A alleles (position 1067) were similar among patients with and without coronary obstructions (p = 0.52 and p= 0.44, respectively). These results show that the Lewis system is not associated with the presence of coronary artery obstruction and do not support the proposition that the Le(a-b-) red blood cell phenotype represents a risk marker for this disease among Brazilian patients.

A transmissão da malária no Brasil é heterogênea em todas as áreas endêmicas e a presença de portadores assintomáticos de Plasmodium sp. (PAPs) na Amazônia brasileira já foi demonstrada. A triagem de pacientes maláricos em bancos de sangue é baseada na seleção dos doadores com relação aos riscos possíveis associados com residência, evidência clínica e/ou os métodos diagnósticos não acurados que aumentam a probabilidade da infecção transmitida por transfusão. Avaliamos a freqüência de PAPs em quatro bancos de sangue em áreas distintas da região Amazônica brasileira. O DNA foi obtido a partir de 400 amostras de sangue humano usando o método do fenol-clorofórmio, seguido por um protocolo de nested-PCR com oligonucleotídeos espécie-específicos. A taxa de positividade variou de 1 a 3% de doadores do sangue das quatro áreas, com uma média de 2,3%. Todos os indivíduos positivos tinham infecções mistas entre o Plasmodium vivax e o Plasmodium falciparum. Nenhuma diferença significativa nos resultados foi detectada entre estas áreas; a maioria dos casos originou dos Hemocentros de Porto Velho, do Estado de Rondônia e de Macapá, Estado do Amapá. Embora ainda não esteja claro se os indivíduos PAPs possam agir como reservatórios do parasito, a triagem eficiente de PAPs e de pacientes com malária em bancos de sangue no Brasil das áreas endêmicas necessita ser implementada.

The transmission of malaria in Brazil is heterogeneous throughout endemic areas and the presence of asymptomatic Plasmodium sp. carriers (APCs) in the Brazilian Amazon has already been demonstrated. Malaria screening in blood banks is based on the selection of donors in respect to possible risks associated with travel or residence, clinical evidence and/or inaccurate diagnostic methods thereby increasing the probability of transfusion-transmitted infection. We evaluated the frequency of APCs in four blood services in distinct areas of the Brazilian Amazon region. DNA was obtained from 400 human blood samples for testing using the phenol-chloroform method followed by a nested-PCR protocol with species-specific primers. The positivity rate varied from 1 to 3% of blood donors from the four areas with an average of 2.3%. All positive individuals had mixed infections for Plasmodium vivax and Plasmodium falciparum. No significant differences in the results were detected among these areas; the majority of cases originated from the transfusion centres of Porto Velho, Rondônia State and Macapá, Amapá State. Although it is still unclear whether APC individuals may act as reservoirs of the parasite, efficient screening of APCs and malaria patients in Brazilian blood services from endemic areas needs to be improved.

CONTEXTO: Estudos epidemiológicos evidenciaram alta freqüência do tipo O e do fenótipo não-secretor dos antígenos ABH em pacientes com úlceras pépticas. Desde que o Helicobacter pylori foi estabelecido como o principal agente etiológico destas doenças, controvérsias sobre as associações dos grupos sangüíneos ABO, Lewis e dos fenótipos secretor e não-secretor com a suscetibilidade à infecção por esse bacilo foram apresentadas. OBJETIVO: Verificar as freqüências dos fenótipos ABO, Lewis, secretor e não-secretor em pacientes infectados ou não infectados pelo H. pylori. TIPO DE ESTUDO: Estudo transversal. LOCAL: Ambulatório de Gastroenterologia do Hospital de Base de São José do Rio Preto e Laboratório de Imunogenética Molecular do Hemocentro de São José do Rio Preto. PARTICIPANTES: Foram avaliados 120 pacientes com sintomas de dispepsia submetidos a endoscopia digestiva alta. VARIÁVEIS ESTUDADAS: Fenótipos eritrocitários ABO e Lewis determinados pelos métodos de hemaglutinação padronizados e fenótipos secretor e não-secretor pelo método de inibição de hemaglutinação. RESULTADOS: O diagnóstico de infecção e não-infecção, realizado pelos testes respiratório e da urease, e confirmado pelo método da reação de polimerase em cadeia (PCR) em fragmentos de biópsias gástricas demonstrou a presença do H. pylori em 61,7% dos pacientes e ausência em 38,3%. As diferenças nas freqüências dos grupos sangüíneos ABO entre os pacientes infectados (A 27,0%; B 12,2%; AB 4,0%; O 56,8%) e não-infectados (A 58,7%; B 13,0%; AB 4,3%; O 24,0%) foram significantes. Os tipos sangüíneos Lewis e os fenótipos secretor e não-secretor mostraram distribuição semelhante entre os grupos de pacientes analisados. CONCLUSÕES: Os resultados sugerem que a infecção pelo H. pylori parece ser influenciada pelos fenótipos ABO, mas não pelos fenótipos Lewis, secretor e não-secretor.

CONTEXT: Epidemiological studies have demonstrated higher frequencies of the O blood group and the non-secretor phenotype of ABH antigens among patients suffering from peptic ulcers. Since Helicobacter pylori has been established as the main etiological factor in this disease, controversies about the associations of the ABO and Lewis blood group phenotypes and secretor and non-secretor phenotypes in relation to susceptibility towards infection by this bacillus have been presented. OBJECTIVE: To verify the frequencies of ABO, Lewis blood group phenotypes, secretor and non-secretor phenotypes in patients infected or uninfected by H. pylori. DESIGN: Cross-sectional study. SETTING: Outpatient clinic. PARTICIPANTS: One hundred and twenty patients with dyspeptic symptoms who underwent endoscopy.MAIN MEASUREMENTS: ABO and Lewis blood group phenotypes were determined by a standard hemagglutination test and the secretor and non-secretor phenotypes were evaluated by saliva samples using the inhibitor hemagglutination test. RESULTS: The diagnosis of infection, made via breath and urea tests and confirmed using polymerase chain reaction (PCR) in gastric biopsy fragments, showed the presence of H. pylori in 61.7% of the patients and absence in 38.3%. The differences between the frequencies of the ABO blood group phenotypes among infected (A 27.0%; B 12.2%; AB 4.0% and O 56.8%) and uninfected patients (A 58.7%; B 13.0%; AB 4.3% and O 24.0%) were significant. The Lewis blood type, secretor and non-secretor phenotypes showed homogeneous distribution between the groups of patients analyzed. CONCLUSIONS: Our results suggest that the infection of H. pylori can be related to ABO blood groups but not to the Lewis blood group nor to secretor and non-secretor phenotypes.