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Type 1 diabetes-associated antibodies during pregnancy and in infancyHämäläinen, A.-M. (Anu-Maaria) 24 October 2001 (has links)
Abstract
There is evidence that the process leading to type 1 diabetes may start in early infancy or even in
utero, with a prodrome of variable duration preceding clinical manifestation. The purpose of the present
work was to learn more about the occurrence and significance of humoral beta-cell autoimmunity during pregnancy and in
infancy, to search for possible signs of prenatal or early postnatal induction of beta-cell autoimmunity and to explore
the role of enterovirus infections as potential triggers of such autoimmunity.
The population comprised mothers and their newborn infants from families with type 1 diabetes who had entered the
first
(n=20) or the second pilot study (n=208) of the Trial to Reduce IDDM in the Genetically at Risk (TRIGR). Almost 40% of
the mothers with type 1 diabetes had antibodies to islet cells (ICA), 55% to glutamic acid decarboxylase (GADA) and 54%
to the IA-2 protein (IA-2A) in the two samples taken during pregnancy, where the frequencies for the unaffected mothers
were 5%, 5% and 3%, respectively. All autoantibody specificities were detected in the cord blood largely at the same
frequencies as in the maternal circulation. In addition, ICA was found in 2.7%, GADA in 0.6%, IA-2A in 0.3% and insulin
autoantibodies (IAA) in 0.1% out of a series of 1002 cord blood samples from infants representing the normal
population. None of the infants of the autoantibody-negative mothers in these series had autoantibodies detectable in
their cord blood.
The rate of decline of transplacentally transferred autoantibodies during the first months of life was observed
to be
similar to that reported for the disappearance of maternally acquired IgG antibodies, the estimated mean elimination
time ranging from 3.1-4.5 months. The higher the initial autoantibody level, the longer was the elimination time, and
transplacentally transferred autoantibodies were occasionally detected up to the age of 9-12 months, and even at 15
months in a very few cases.
The peak incidence of enterovirus RNA in serum was observed at the age of 6-12 months, while that of infections,
based
on changes in antibody titres, was seen at the age of 18 months. The frequency of enterovirus infections in the
autoantibody-positive infants during the 6 months before the appearance of the first autoantibodies was almost three
times higher than in age-matched infants testing negative for autoantibodies.
These observations suggest that pregnancy does not have any strong modulating effect on the prevalence and titres
of
diabetes-associated autoantibodies. If such autoantibodies are present in the mother, most of them are transferred to
the foetal circulation and are detectable in the cord blood. No signs of foetal induction of beta-cell autoimmunity
were observed, indicating that such a phenomenon is extremely rare. Most of the transplacentally transferred
autoantibodies disappear within the first 3-6 months of postnatal life, but they may persist even up to the age of 15
months in exceptional cases, suggesting that the optimal age for the initiation of large-scale screening in the general
population is 18-24 months. The temporal association between enterovirus infections and the first signs of beta-cell
autoimmunity supports the hypothesis that enteroviruses may induce a primary beta-cell insult.
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Murine neonatal skin mast cells are phenotypically immature and minimally sensitized with transplacentally transferred IgE / 新生仔マウス皮膚肥満細胞は未熟であるために、経胎盤移行した母体由来IgEに感作されにくいKeith(Honda), Yuki 27 July 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第22686号 / 医博第4630号 / 新制||医||1045(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 生田 宏一, 教授 竹内 理, 教授 杉田 昌彦 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
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Aquisição passiva de anticorpos IgG maternos reativos com os lipopolissacarídeos de enterobactérias incidentes em infecções neonatais por recém-nascidos pré-termos e a termo. / Passive acquisition of maternal IgG antibodies reactive to lipopolysaccharide from enterobacteria incident in neonatal infections by preterm and term neonates.Marques, Ana Lúcia Silveira Lessa 24 March 2009 (has links)
As espécies Klebsiella pneumoniae, Escherichia coli e Pseudomonas aeruginosa são responsáveis por infecções neonatais hospitalares. Lipopolissacarídeo (LPS) é o principal indutor de respostas inflamatórias. Os objetivos foram avaliar a transferência placentária de IgG reativa ao LPS de K. pneumoniae, E. coli O111, O26 e O6 e P. aeruginosa empregando ELISA para dosar IgG em soro materno e de cordão de 29 neonatos pré-termos e 32 a termo; analisar IgM total e específica no soro materno; e investigar a influência das patologias apresentadas pelas mães na transferência placentária. Concentrações de IgG total foram reduzidas em pré-termos como esperado, porem índices de transferência placentária de IgG total e IgG anti-LPS foram sistematicamente reduzidos quando comparados aos neonatos a termo. Níveis de IgM total e anti-LPS foram equivalentes em mães de ambos os grupos. As patologias das mães influenciaram os níveis de IgM no grupo de mães de pré-termos. Estes resultados indicam uma imunidade adquirida deficiente pelo grupo pré-termo aumentando os riscos de infecção. / Klebsiella pneumoniae, Escherichia coli and Pseudomonas aeruginosa species are responsible for neonatal nosocomial infections. Bacterial lipopolysaccharide (LPS) is the major inducer of the inflammatory responses. The aims were to evaluate the placental transfer of IgG reactive to LPS present in K. pneumoniae, in E. coli O111, O26 and O6 and in P. aeruginosa employing ELISA to detect IgG in maternal and cord sera from 29 preterm and 32 term neonates; to analyze total and specific IgM on the mothers sera; and to investigate the influence of the pathologies presented by some mothers in the placental transfer. Total IgG concentrations were reduced in preterm neonates as expected, but placental transfer indexes of total and anti-LPS IgG were systematically reduced when compared with term neonates. Total and anti-LPS IgM levels were equivalent on mothers of both groups. The mothers pathologies influenced only the IgM levels in the preterm mothers group. These results indicate a deficient acquired immunity by the preterm group increasing the risk of infection.
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Aquisição passiva de anticorpos IgG maternos reativos com os lipopolissacarídeos de enterobactérias incidentes em infecções neonatais por recém-nascidos pré-termos e a termo. / Passive acquisition of maternal IgG antibodies reactive to lipopolysaccharide from enterobacteria incident in neonatal infections by preterm and term neonates.Ana Lúcia Silveira Lessa Marques 24 March 2009 (has links)
As espécies Klebsiella pneumoniae, Escherichia coli e Pseudomonas aeruginosa são responsáveis por infecções neonatais hospitalares. Lipopolissacarídeo (LPS) é o principal indutor de respostas inflamatórias. Os objetivos foram avaliar a transferência placentária de IgG reativa ao LPS de K. pneumoniae, E. coli O111, O26 e O6 e P. aeruginosa empregando ELISA para dosar IgG em soro materno e de cordão de 29 neonatos pré-termos e 32 a termo; analisar IgM total e específica no soro materno; e investigar a influência das patologias apresentadas pelas mães na transferência placentária. Concentrações de IgG total foram reduzidas em pré-termos como esperado, porem índices de transferência placentária de IgG total e IgG anti-LPS foram sistematicamente reduzidos quando comparados aos neonatos a termo. Níveis de IgM total e anti-LPS foram equivalentes em mães de ambos os grupos. As patologias das mães influenciaram os níveis de IgM no grupo de mães de pré-termos. Estes resultados indicam uma imunidade adquirida deficiente pelo grupo pré-termo aumentando os riscos de infecção. / Klebsiella pneumoniae, Escherichia coli and Pseudomonas aeruginosa species are responsible for neonatal nosocomial infections. Bacterial lipopolysaccharide (LPS) is the major inducer of the inflammatory responses. The aims were to evaluate the placental transfer of IgG reactive to LPS present in K. pneumoniae, in E. coli O111, O26 and O6 and in P. aeruginosa employing ELISA to detect IgG in maternal and cord sera from 29 preterm and 32 term neonates; to analyze total and specific IgM on the mothers sera; and to investigate the influence of the pathologies presented by some mothers in the placental transfer. Total IgG concentrations were reduced in preterm neonates as expected, but placental transfer indexes of total and anti-LPS IgG were systematically reduced when compared with term neonates. Total and anti-LPS IgM levels were equivalent on mothers of both groups. The mothers pathologies influenced only the IgM levels in the preterm mothers group. These results indicate a deficient acquired immunity by the preterm group increasing the risk of infection.
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