Placental and colostral transfer of antibodies reactive with enteropathogenic Escherichia coli intimins α, ß, or γ / Transferência placentária e colostral de anticorpos reativos a Escherichia coli enteropatogênica com expressão das intiminas α, ß, or γ

Abstract Objective: Intimins are protein adhesins of enteropathogenic Escherichia coli and enterohemorrhagic E. coli capable of inducing attachment and effacement lesions in enterocytes. Anti-intimin antibodies are important for the protection from enteropathogenic E. coli and enterohemorrhagic E. coli infections because these antibodies inhibit bacterial adhesion and impair the initial step of the pathogenesis. We studied the transfer of maternal anti-intimin antibodies from healthy Brazilian mothers to their newborns through the placenta and colostrum. Methods: Serum immunoglobulin G and secretory immunoglobulin A antibodies against conserved and variable regions of intimins α, β, and γ were analyzed using an enzyme linked-immunosorbent assay in the blood and colostrum from 45 healthy women as well as cord blood serum samples from their newborns. Results: The concentrations of antibodies reactive with α intimin were significantly lower than those of anti-γ and anti-conserved intimin antibodies in the colostrum samples. IgG serum antibodies reactive with all the subtypes of intimins were transferred to the newborns, but the concentrations of anti-conserved intimin serum antibodies were significantly higher in mothers and newborns than concentrations of antibodies against variable regions. The patterns of IgG transfer from mothers to newborns were similar for all anti-intimin antibodies. These values are similar to the percentage transference of total IgG. Conclusions: Anti-intimin antibodies are transferred from mothers to newborns through the placenta, and reinforce the protection provided by breastfeeding against diarrheagenic E. coli infections.

Resumo Objetivo: As intiminas são adesinas proteicas de Escherichia coli enteropatogênicas (EPEC) e enterro-hemorrágicas (EHEC) capazes de induzir as lesões attaching and effacing nos enterócitos. Anticorpos anti-intiminas são importantes para a proteção contra infecções por EPEC e EHEC porque esses anticorpos inibem a adesão bacteriana e impedem o passo inicial do mecanismo patogênico dessas bactérias. Nós estudamos a transferência de anticorpos maternos anti-intiminas de mães brasileiras saudáveis para os seus recém-nascidos através da placenta e do colostro. Métodos: Anticorpos séricos da classe IgG e secretórios da classe IgA (SIgA) reativos com as porções conservada (cons) e variáveis das intiminas α (vα), β (vβ) e γ (vγ) foram analisados pelo teste de ELISA no sangue e no colostro de 45 parturientes saudáveis e no sangue de cordão umbilical dos seus respectivos recém-nascidos. Resultados: As concentrações de anticorpos reativos com intimina vα foram significativamente mais baixas que as dos anticorpos anti-vγ e anti-cons nas amostras de colostro. Anticorpos IgG séricos reativos com todas as intiminas foram transferidos para os recém-nascidos, mas as concentrações de anti-cons foram significativamente mais altas tanto nas mães como nos recém-nascidos do que os anticorpos reativos com as regiões variáveis das intiminas. O padrão de transferência de IgG das mães para os recém-nascidos foi muito semelhante para todos os anticorpos anti-intiminas. Os valores de porcentagem de transferência foram semelhantes à transferência de IgG total. Conclusões: Anticorpos anti-intimina são transferidos das mães para os recém-nascidos pela placenta e corroboram a proteção contra infecções por Escherichia coli diarreiogênicas (DEC) conferida pelo aleitamento materno.

Placental and colostral transfer of antibodies reactive with enteropathogenic Escherichia coli intimins α, ß, or γ.

OBJECTIVE: Intimins are protein adhesins of enteropathogenic Escherichia coli and enterohemorrhagic E. coli capable of inducing attachment and effacement lesions in enterocytes. Anti-intimin antibodies are important for the protection from enteropathogenic E. coli and enterohemorrhagic E. coli infections because these antibodies inhibit bacterial adhesion and impair the initial step of the pathogenesis. We studied the transfer of maternal anti-intimin antibodies from healthy Brazilian mothers to their newborns through the placenta and colostrum. METHODS: Serum immunoglobulin G and secretory immunoglobulin A antibodies against conserved and variable regions of intimins α, ß, and γ were analyzed using an enzyme linked-immunosorbent assay in the blood and colostrum from 45 healthy women as well as cord blood serum samples from their newborns. RESULTS: The concentrations of antibodies reactive with α intimin were significantly lower than those of anti-γ and anti-conserved intimin antibodies in the colostrum samples. IgG serum antibodies reactive with all the subtypes of intimins were transferred to the newborns, but the concentrations of anti-conserved intimin serum antibodies were significantly higher in mothers and newborns than concentrations of antibodies against variable regions. The patterns of IgG transfer from mothers to newborns were similar for all anti-intimin antibodies. These values are similar to the percentage transference of total IgG. CONCLUSIONS: Anti-intimin antibodies are transferred from mothers to newborns through the placenta, and reinforce the protection provided by breastfeeding against diarrheagenic E. coli infections.

Detection of secretory immunoglobulin A in human colostrum as mucosal immune response against proteins of the type III secretion system of Salmonella, Shigella and enteropathogenic Escherichia coli.

BACKGROUND: Some enteropathogens use the type III secretion system to secrete proteins that allows them to interact with enterocytes and promote bacterial attachment or intracellular survival. These proteins are Salmonella invasion proteins (Sip), invasion plasmid antigens (Ipa) of Shigella and Escherichia coli secreted proteins (Esp) of enteropathogenic E. coli. There are no previous studies defining the presence of colostral sIgA against all these 3 major enteric pathogens. OBJECTIVE: To evaluate the presence of sIgA in colostrum against proteins of the type III secretion system of Salmonella, Shigella and enteropathogenic E. coli. METHODS: We collected 76 colostrum samples from puerperal women in Lima, Peru. These samples were reacted with type III secretion system proteins extracted from bacterial culture supernatants and evaluated by Western Blot. RESULTS: Antibodies were detected against Salmonella antigens SipA in 75 samples (99%), SipC in 62 (82%) and SipB in 31 (41%); against Shigella antigens IpaC in 70 (92%), IpaB in 68 (89%), IpaA in 66 (87%) and IpaD in 41 (54%); and against enteropathogenic E. coli EspC in 70 (92%), EspB-D in 65 (86%) and EspA in 41 (54%). Ten percent of samples had antibodies against all proteins evaluated and 42% against all except 1 protein. There was no sample negative to all these proteins. CONCLUSIONS: The extraordinarily high frequency of antibodies in colostrum of puerperal women detected in this study against these multiple enteric pathogens shows evidence of immunological memory and prior exposure to these pathogens, in addition to its possible protective role against infection.

Anticorpos anti-intiminas α, β, e γ de Escherichia coli em soros e colostros de adultos saudáveis da Grande São Paulo / Antibodies reactive with α, β,and γ intimins of Escherichia coli in serum and colostrum samples of healthy adults living in São Paulo, Brazil

A diarréia é um importante problema de saúde pública no mundo inteiro e a Escherichía coli é um dos mais freqüentes microorganismos causadores desta doença. A Escherichia coli enteropatogênica (EPEC), um dos principais agentes etiológicos das diarréias infantis no nosso país, é genética e fenotipicamente relacionada com a E. colí enterohemorrágica (EHEC) que além de provocar diarréia é responsável por complicações como síndrome hemolítica urêmica (HUS) e colite hemorrágica (HC). Embora a EHEC seja considerada emergente pela OMS, no Brasil poucos casos de complicações como HUS e HC foram reportados. O mecanismo de patogenicidade comum entre EPEC e EHEC é conhecido como a lesão "attaching and effacing" nos microvilos do enterócito. Esta lesão é mediada por um conjunto de fatores de virulência, dentre eles a intimina. A intimina é uma proteína de membrana externa, responsável pelo íntimo contato da bactéria com o enterócito, possui uma região N-terminal que é altamente conservada e uma região C-terminal que é variável. De acordo com a região variável, existem vários subtipos de intimina, dentre eles as intiminas , α, β e γ...

Tackling multiple antibiotic resistance in enteropathogenic Escherichia coli (EPEC) clinical isolates: a diarylheptanoid from Alpinia officinarum shows promising antibacterial and immunomodulatory activity against EPEC and its lipopolysaccharide-induced inflammation.

Antibiotic treatment for infectious diseases commonly leads to host inflammatory responses. Molecules with bifunctional antibacterial and anti-inflammatory properties could provide a solution for such clinical manifestations. Here we report such bifunctional activity for a diarylheptanoid (5-hydroxy-7-(4''-hydroxy-3-methoxyphenyl)-1-phenyl-3-heptanone) isolated from Alpinia officinarum, a medicinal plant belonging to the Zingiberaceae family, against enteropathogenic Escherichia coli (EPEC). The diarylheptanoid showed inhibitory and bactericidal activity against EPEC clinical isolates and efficiently suppressed EPEC lipopolysaccharide-induced inflammation in human peripheral blood mononuclear cells. In silico docking analysis revealed that the diarylheptanoid could interact with subunit A of E. coli DNA gyrase. Such molecules with bifunctional activity may be potential therapeutics for infectious diseases.