Analysis of colostrum IgA against bacteria involved in neonatal infections / Análise de IgA do colostro contra bactérias envolvidas em infecções neonatais

ABSTRACT Objective To describe e compare the specificity of IgA antibodies against bacteria extract of Klebsiella pneumoniae , Staphylococcus aureus , Escherichia coli , and Salmonella enteritidis . Methods Colostrum samples were aseptically collected in the first 12 hours after C-section delivery. The specificity of IgA against bacteria extracts was analyzed by the Western blot. Results The findings showed proteins of high molecular weight frequently detectable in the samples. S. aureus was the most frequently found bacterium in the samples (p<0.05). Approximately 93.8, 56.3, 62.5 and 60.4% of samples presented IgA reactive to S. aureus , K. pneumoniae , S. enteritidis, and E. coli, respectively. Roughly 40% of samples showed no IgA reactive to K. pneumoniae, S. enteritidis and E. coli . Conclusion Clinical evidence of the importance of breastfeeding for the immune protection of neonates was consistent with the observed immunological findings, since most samples showed IgA reactive against the species tested. The application and development of immunotherapies during pregnancy, focused on frequently detected antigens, could be an important tool to enhance the presence of IgA in colostrum.

RESUMO Objetivo Descrever e comparar a especificidade de anticorpos IgA de amostras de colostro contra extratos bacterianos de Klebsiella pneumoniae , Staphylococcus aureus , Escherichia coli e Salmonella enteritidis . Métodos As amostras de colostro foram coletadas assepticamente nas primeiras 12 horas após o nascimento por cesariana. A especificidade de IgA contra extratos de bactérias foi analisada por Western blot. Resultados Os achados mostraram proteínas de alto peso molecular frequentemente detectáveis nas amostras. S. aureus foi a bactéria mais encontrada nas amostras (p<0,05). Cerca de 93,8, 56,3, 62,5 e 60,4% das amostras apresentaram IgA reativa a S. aureus , K. pneumoniae , S. enteritidis e E. coli , respectivamente. Aproximadamente 40% das amostras não apresentaram IgA reativa contra K. pneumoniae , S. enteritidis e E. coli. Conclusão A evidência clínica da importância da amamentação para proteção imunológica ao recém-nascido foi consistente com os achados imunológicos observados, uma vez que a maioria das amostras mostrou IgA reativa contra as espécies testadas. A aplicação e o desenvolvimento de imunoterapias durante a gestação, focada nos antígenos frequentemente detectados, poderiam ser importantes instrumentos para aumentar a presença de IgA no colostro.

Comparisons of IgA response in saliva and colostrum against oral streptococci species

Abstract The present study compared IgA specificity against oral streptococci in colostrum and saliva samples. Sixty-two mother-and-child pairs were included; samples of colostrum (C) and saliva (MS) were collected from the mothers and saliva samples were collected from babies (BS). The specificity of IgA against Streptococcus mutans and S. mitis were analyzed by western blot. Only 30% of babies’ samples presented IgA reactivity to S. mutans, while 74 and 80% of MS and C, respectively, presented this response. IgA reactivity to S. mutans virulence antigens (Ag I/II, Gtf and GbpB) in positive samples showed differences between samples for Gtf and especially for GbpB (p < 0.05), but responses to Ag I/II were similar (p > 0.05). The positive response of Gtf-reactive IgA was different between C (90%) and MS (58%) samples (p < 0.05), but did not differ from BS (p > 0.05). GbpB was the least detected, with 48 and 26% of C and MS, and only 5% of BS samples presenting reactivity (p > 0.05). Eight percent of MS and C samples presented identical bands to SM in the same time-point. In conclusion, the differences of IgA response found between C and MS can be due to the different ways of stimulation, proliferation and transportation of IgA in those secretions. The colostrum has high levels of IgA against S. mutans virulence antigens, which could affect the installation and accumulation process of S. mutans, mainly by supplying anti-GbpB IgA to the neonate.

Rol de la microbiota gastrointestinal en la regulación de la respuesta inmune / The role of gut microbiota in the regulation of the immune response

The gastrointestinal tract hosts around 10(14) bacterial microorganisms, in a constantly growing density from the stomach to the distal colon. This microbiota is composed by more than 500 species of bacteria, which are quickly acquired after birth, fairly stable during the host’s life, and essential for human homeostasis. These bacteria have important functions, such as stimulating the immune system, protecting the host from invading bacteria and viruses, and improving digestion, especially of complex carbohydrates. Also, the gut microbiota interacts directly with the immune system. However, the interaction of the intestinal epithelium and its microbiota with the immune system has yet to be fully understood. Secretory immunoglobulin A, produced by the plasma cells in Peyer’s patches and in the lamina propria, maintains non-invasive commensal bacteria and neutralize invasive pathogens. Dendritic cells migrate from the lamina propria of the secondary lymphoid organs to regulate gut immunity. They also have a key role maintaining luminal IgA and inducing the growth of regulatory T cells. Dendritic cells supervise the gut microenvironment too, keeping an immunological equilibrium and tolerance. The importance of the gut microbiota in regulating the immune system lies mostly in the homeostasis-or positive equilibrium. Thus, many diseases are a consequence of poor interactions or a loss of this equilibrium.

Anti-dentine Salivary SIgA in young adults with a history of dental trauma in deciduous teeth

Anti-dentin autoantibodies are associated with inflammatory root resorption in permanent teeth and are modulated by dental trauma and orthodontic force. However, it is not known whether deciduous tooth trauma can stimulate the development of a humoral immune response against dentin. The aim of this study was to evaluate the levels of salivary SIgA reactivity against human dentin extract in young adults with a history of trauma in the primary dentition. A sample of 78 patients, aged 18 to 25, who had completed an early childhood (0 to 5 years old) caries prevention program years earlier at the Universidade Estadual de LondrinaPediatric Clinic, underwent radiographic examination and salivary sampling. Anti-dentin SIgA levels were analyzed by immunoenzymatic assay and Western blotting. Although dental trauma to deciduous teeth had occurred in 34 (43.6%) of the patients, no differences in SIgA levels were detected between individuals who had experienced trauma and those who had not (p > 0.05). Multivariate regression analysis showed no association between dental trauma and SIgA levels (p > 0.05). Patients with a history of deciduous trauma presented low levels of anti-dentin antibodies, associated with orthodontic root resorption (p < 0.05). Western blot analysis showed that salivary antibodies recognized a single band of approximately 45 kDa in dentin extract. We concluded that salivary SIgA recognizes a specific component of the dentin matrix and that anti-dentin antibodies were not triggered by trauma to primary teeth. However, trauma to deciduous teeth may down-modulate SIgA in response to orthodontic root response.

Reduction of the amount of intestinal secretory IgA in fulminant hepatic failure

Intestinal barrier dysfunction plays an important role in spontaneous bacterial peritonitis. In the present study, changes in the intestinal barrier with regard to levels of secretory immunoglobulin A (SIgA) and its components were studied in fulminant hepatic failure (FHF). Immunohistochemistry and double immunofluorescent staining were used to detect intestinal IgA, the secretory component (SC) and SIgA in patients with FHF (20 patients) and in an animal model with FHF (120 mice). Real-time PCR was used to detect intestinal SC mRNA in the animal model with FHF. Intestinal SIgA, IgA, and SC staining in patients with FHF was significantly weaker than in the normal control group (30 patients). Intestinal IgA and SC staining was significantly weaker in the animal model with FHF than in the control groups (normal saline: 30 mice; lipopolysaccharide: 50 mice; D-galactosamine: 50 mice; FHF: 120 mice). SC mRNA of the animal model with FHF at 2, 6, and 9 h after injection was 0.4 ± 0.02, 0.3 ± 0.01, 0.09 ± 0.01, respectively. SC mRNA of the animal model with FHF was significantly decreased compared to the normal saline group (1.0 ± 0.02) and lipopolysaccharide group (0.89 ± 0.01). The decrease in intestinal SIgA and SC induced failure of the intestinal immunologic barrier and the attenuation of gut immunity in the presence of FHF.

Niveles de Ig A secretoria en niños de 1 a 11 años de edad residentes en la localidad de Coro Coro del departamento de La Paz en el año 2001 / Levels of Ig A secretory in children from 1 to 11 living years old in the locality of choir choir of the department of La Paz in 2001

La inmunidad natural se caracteriza porque forma parte del individuo desde el momento que nace y es inespecífica. Este tipo de inmunidad se compone principalmente de tres barreras importantes como la piel, mucosa y la conjuntiva y junto con sustancias químicas producidas por estas, dan por protección evitando el ingreso de microorganismos. Es bién conocido que las secreciones del epitelio mucoso como saliva, lagrimas y otras cuentan con la presencia de la inmunoglobulina A secretoria.

The secretory immunoglobulin A response to Mycobacterium tuberculosis in a childhood population

We report on the measurement of saliva anti-Purified Protein Derivative sIgA and 38kDa antibodies from 127 children, of whom 31 were strong tuberculosis suspects and 96 were healthy contact children. The results concerning the percentage of children with antibody reactivity to PPD and 38kDa antigens showed that, of these 2 antigens, 38kDa induced higher reactivity in patients positive and negative for the Tuberculin Skin Test (28 percent and 16.6 percent, respectively) in comparison to controls positive and negative for the TST (11.7 percent and 7.1 percent, respectively). There was a statistically significant difference between patients positive and controls negative for the TST. In relation to the Purified Protein Derivative antigen, while 14.2 percent of patients positive for the TST showed antibody reactivity to the PPD antigen, no patients negative for the TST had reactivity to this antigen. The findings suggest that these two antigens seem be associated with a different development of the mucosal defence mechanisms mediated by sIgA against Mycobacterium tuberculosis.

Foram dosados anticorpos sIgA anti-Purified Protein Derivative e 38kDa da saliva de 127 crianças, das quais 31 eram de pacientes altamente suspeitos de tuberculose e 96 eram provenientes de crianças saudáveis, que tiveram contato com pacientes. Os resultados referentes à porcentagem de crianças, reativas ao PPD e ao antígeno 38kDa, mostraram que destes dois antígenos, o 38kDa induziu maior reatividade em pacientes positivos e negativos ao Tuberculin Skin Test (28 por cento e 16,6 por cento, respectivamente), em comparação aos controles positivos e negativos ao TST (11,7 por cento e 7,1 por cento, respectivamente). Houve diferença estatisticamente significativa entre pacientes positivos e controles negativos ao Tuberculin Skin Test. Em relação ao antígeno PPD, enquanto 14,2 por cento de pacientes positivos ao TST mostraram anticorpos reativos ao antígeno Purified Protein Derivative, nenhum paciente negativo ao TST foi reativo ao antígeno. Os achados sugerem que, aparentemente, estes dois antígenos estão associados a desenvolvimento distinto dos mecanismos de defesa da mucosa mediados por sIgA contra Mycobacterium tuberculosis.

Secretory immunoglobulin A: a protective factor in the genital mucosa

The genital mechanisms of defense are not well understood and are therefore ignored during therapy. This fact results in a great number of cases of treatment failure. The mucosa is an important protective factor of the genital female system, through self-defense mechanisms, and secretor antibodies (immunoglobulin A). The lymphoid tissue exerts protective anti-inflammatory activity, besides inhibiting microorganism adherence, neutralizes viruses and toxins and stabilizes the mucosal flora. Although certain microorganisms, such as viruses and fungus, are controlled by cellular immunity, secretory IgA can also exert an important role in the control of these agents.

Doença da IgA linerar - Revisão da Literatura / Linear IgA disease - literature review

A doença por depósito linear de imunoglobulina A (IgA) é um processo mucocutâneo crônico, raro e de origem auto-imune, caracterizado por depósitos lineares do anticorpo ao longo da membrana basal da pele e mucosas. O estudo da enfermidade é de grande importância, visto que a mesma é de complexo diagnóstico e tratamento, além de sua etiopatogenia não estar ainda definida. O presente artigo teve por objetivo revisar a literatura referente à doença da IgA linear, abordando suas características clínicas, diagnóstico diferencial e alternativas de tratamento

The mucosal adjuvanticity of two nontoxic mutants of Escherichia coli heat-labile enterotoxin varies with immunization routes

Escherichia coli heat-labile enterotoxin (LT), which causes a characteristic diarrhea in humans and animals, is a strong mucosal immunogen and has powerful mucosal adjuvant activity towards coadministered unrelated antigens. Here we report the different mucosal adjuvanticity of nontoxic LT derivatives, LTS63Y and LTdelta110/112, generated by immunizing through two different mucosal routes. Intragastric (IG) immunization with Helicobacter pylori urease alone resulted in poor systemic IgG and IgA responses and no detectable local secretory IgA, but IG co-immunization with urease and LTdelta110/112 induced high titers of urease-specific local secretory IgA and systemic IgG and IgA, comparable to those induced by wild-type LT. LTS63Y showed far lower adjuvant activity towards urease than LTdelta110/112 in IG immunization, but was more active than LTdelta110/112 in inducing immune responses to urease by intranasal (IN) immunization. LTdelta110/112 predominantly enhanced the induction of urease-specific IgG1 levels following IG immunization, whereas LTS63Y induced high levels of IgG1, IgG2a and IgG2b following IN immunization. In addition, quantitative H. pylori culture of stomach tissue following challenge with H. pylori demonstrated a 90-95% reduction (p < 0.0002) in bacterial burden in mice immunized intranasally with urease using either mutant LT as an adjuvant. These results indicate that the mechanism(s) underlying the adjuvant activities of mutant LTs towards coadmnistered H. pylori urease may differ between the IN and IG mucosal immunization routes.

Factores salivales de defensa no inmunoglobulínicos: artículo de revisión bibliográfica / Non-immunoglobulinic defense salivary factors: review of the literature

Este trabajo describe y analiza los principales factores antimicrobianos no inmunoglobulínicos de la saliva, su función biológica, interacciones y relación con diversas situaciones fisiológicas y patológicas que pueden presentarse en la cavidad bucal. Finalmente, se reseñan algunas aplicaciones clinicoterapéuticas de estos factores, destacando la necesidad de nuevas investigaciones destinadas a probar otros tratamientos que contribuyan a incrementar la efectividad de los sistemas innatos de defensa

Factores salivales de defensa no inmunoglobulínicos / Non-immunoglobulinic defense salivary factors

Este trabajo describe y analiza los principales factores antimicrobianos no inmunoglobulínicos de la saliva, su función biológica, interacciones y relación con diversas situaciones fisiológicas y patológicas que pueden presentarse en la cavidad bucal. Finalmente, se reseñan algunas aplicaciones clinicoterapéuticas de estos factores, destacando la necesidad de nuevas investigaciones destinadas a probar otros tratamientos que contribuyan a incrementar la efectividad de los sistemas innatos de defensa

Perfil de inmunoglobulinas (Ig) séricas e inmunoglobulinas A secretora (IgA) en pacientes con bloqueo nasal crónico total y permanente (B.N.C.T.y P.) / Profile of serical immunoglobulin (Ig) and secretoral A immunoglobulin (IgA) in patients with total and permanent chronic nasal blockage (TPCNB)

Objetivo: determinar Igs en suero y secreciones de pacientes con bloque nasal crónico total y permanente (B.N.C.T. y P.)a fin de correlacionar estos datos con los hallazgos clínicos y anatomopatológicos. Material y métodos: Se estudiaron 17 pacientes de ambos sexos de 11 a 30 años. Se realizó estudio anatomopatológico de biopsias de mucosa nasal. Resultados: IgG: 11,76 por ciento disminuida. IgA sérica: normal en todos los pacientes, IgA en saliva: 64,7 por ciento disminuida y en un caso, no detectable. IgA en moco nasal: 35,3 por ciento muy disminuida y en 7 casos, no detectable. La IgE fue elevada en el 35,3 por ciento de los casos. Conclusiones: De los resultados obtenidos, se infiere que los pacientes con B.N.C.T. y P., tienen un perfil de IgA en saliva y moco nasal deficitario debido a las alteraciones de la mucosa nasal en distintos estadíos evolutivos que conducen al B.N.C.T. y P., hecho que se correlaciona con los hallazgos anatomopatológicos

IgA secretora en lagrimas de pacientes con conjuntivitis hemorragica por Coxsackie A 24 / Secretory IgA in tears in patients with Coxsackie A 24 hemorrhagic conjunctivitis

Se estudiaron 177 pacientes en edades comprendidas entre 3 y 16 años afectados de conjuntivitis hemorrágica producida por el virus Coxsackie A 24. Se tomaron muestras de lágrimas a todos lo pacientes y se cuantificóIgA secretora, título de anticuerpos neutralizantes contra el virus y el pH de la lágrima. La IgA secretora detectada en la fase aguda confirió poca protección demostrada por bajo el título de anticuerpos neutralizantes contra el virus. En cambio, en la segunda muestra tomada a los 30 días se encuentra un incremento significativo del título de anticuerpos específicos. En la mayoría de los pacientes el pH disminuyó o permaneció constante a los 30 días

Colonic immunity in patients and amoebic liver abscess.

Secretory immunoglobulin A (S-IgA), coproantibody titre (antiamoebic) and IgA, IgG, IgM immunocytes in rectal mucosa were studied in 13 patients with amoebic liver abscess (ALA) prior to and 4-6 weeks after completion of antiamoebic therapy. Ten asymptomatic Entamoeba histolytica cyst passers and 17 healthy age and sex matched volunteers served as controls. Fecal S-IgA levels and counts of IgA bearing immunocytes in mucosa were significantly higher in patients with ALA and cyst passers as compared to healthy controls and showed a significant fall after treatment. Fecal antiamoebic antibodies were high in cyst passers and in cases of ALA after treatment. Raised levels of S-IgA and IgA class immunocyte counts probably indicate a local mucosal immune response directed at containing the infection.

Immunoassays of secretory IgA and secretory component

1. A sandwich-type enzyme-linked immunosorbent (ELISA) is described for quantitation of secretory IgA (sIgA) in human serum, as well as an ELISA and a radioimmunoassay (RIA) for measurement of secretory component (SC) is human serum. Samples were reduced and alkylated prior to the measurement of SC. 2. Healthy individuals (N = 53) presented low levels of SC (median, 0.9 mg/l). The protein levels were significantly elevated when compared with the controls, in sera of women during the second (N = 31; median, 1.5 mg/l) and third (N = 35; median, 2.4 mg/l) and acute viral hepatitis (N = 25; median 2.4 mg/l). SC levels of women in the first trimester of pregnancy (N = 24; median, 0.5 mg/l) did not differ from the controls. 3. sIgA levels were also significantly elevated when sera of women in the third trimester of pregnancy (N = 41; median, 25.4 mg/l) and sera of patients with alcoholic cirrhosis (N = 32; median, 75.0 mg/l) or acute viral hepatitis (N = 38; median, 28.5 mg/l) were compared with controls (N = 49; median, 9.0 mg/l). women in the first (N = 25; median, 7.7 mg/l) and second (N = 29; median, 10.2 mg/l trimester of pregnancy did not present levels statistically different from the controls. 4. The results obtained for SC by RIA and ELISA were positively correlated (rs = 0.88; P < 0.001). sIgA levels determined by ELISA were also positively correlated with the results of RIA-SC(rs = 0.77;P<0.001) or ELISA-SC (rs = 0.79; P < 0.001). 5. The assays described are specific, relatively simple to perform, and can be useful for the study of the secretory system

Determinación de inmunoglobulina a secretora ancicisticerco en saliva en pacientes adultos con neurocisticercosis: estudio prospectivo de 21 pacientes con neurocisticercosis diagnosticados en el departamento de Neurocirugía del Hospital ...

La neurocisticercosis es una enfermedad que se observa principalmente en países pobres con déficit en educación en sus habitantes y falta de higiene. Guatemala es un país en el que la Neurocisticercosis tiene una frecuencia del uno a dos por ciento hipotéticamente, por lo que es necesario hacer estudios epidemiológicos con examen de laboratorio confiable y no invasivo que permita establecer una incidencia real en la población. Además este estudio es el primero que se efectúa en relación a anticuerpos IgA secretora anticisticerco en saliva. La población estudiada fueron 21 pacientes adultos con Neurocisticercosis de uno u otro sexo y 21 pacientes como grupo control clínicamente normales. La determinación de los anticuerpos IgA anticisticerco en saliva se hizo con la técnica de ensayo inmunoenzimático en fase sólida (ELISA). Los resultados fueron que de 21 pacientes con Neurocisticercosis demostrada 18 pacientes fueron positivos o sea el 86% y del grupo comtrol fueron positivos 7 pacientes o sea el 33.33%, con lo cual la sensibilidad del método es de 0.86 y especificidad de 0.66 que es similar a la reportada en suero y líquido cefalorraquídeo con la ventaja que este método no es invasivo. De los 7 pacientes controles positivos lo podría explicar factores como la presencia de la enfermedad en forma asintomática o bien la presencia de parasitismo que pueda interferir en la estimulación del sistema inmune secretor; también pudo haber sido por la falta de dilución de las muestras de saliva refiriéndonos a una técnica que no afecte la especialidad