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1.
Int. j. morphol ; 40(5): 1228-1235, 2022. ilus, tab, graf
Article Dans Anglais | LILACS | ID: biblio-1405276

Résumé

SUMMARY: The aim of our study was to investigate the effect of inflammation in the placenta on the pro-apoptotic development after severe preeclampsia. Placenta tissue samples of 15 HELLP syndrome and 15 healthy 35-38th week-pregnant women were involved in the study. Tissue samples were taken only from the maternal side of the placenta and fixed in 10 % formaldehyde, then blocked in paraffin wax and 4-6 mm-thick sections were cut and stained with Harris Hematoxylene-Eosin. Antigen retrieval was performed for sections, incubated with FAS antibody and anti-IL-6 antibody. After the application of streptavidin peroxidase followed by AEC chromogen solution, sections were counterstained with Harris hematoxylin. Significant thickening of the fibrinoid layer, degeneration and apoptotic change in decidua cells, marked increase in the hyalinized area, degenerative changes in the syncytial regions of the chorionic villus and an increase in syncytial nodes and bridges and IL- expression were observed as positive. FAS expression was positive in the pycnotic nuclei of decidual cells in the maternal region and in the syncytial regions. It was observed that the proapoptotic process increased as a result of severe preeclampsia. It was concluded that the control of cytokine activity and reduction of pro-apoptotic signal during the inflammation process will slow down the development of HELLP syndrome.


RESUMEN: El objetivo de nuestro estudio fue investigar el efecto de la inflamación en la placenta sobre el desarrollo proapoptótico después de la preeclampsia severa. Se recogieron muestras de tejido de placenta de 15 mujeres con síndrome de HELLP y 15 mujeres sanas con un embarazo de 35 a 38 semanas. Se tomaron muestras de tejido solo del lado materno de la placenta y se fijaron en formaldehído al 10 %, luego se bloquearon en parafina y se cortaron secciones de 4-6 mm de espesor y se tiñeron con hematoxilena-eosina de Harris. La recuperación del antígeno se realizó para secciones, incubadas con anticuerpo FAS y anticuerpo anti-IL-6. Después de la aplicación de estreptavidina peroxidasa seguida de solución de cromógeno AEC, las secciones se contrastaron con hematoxilina de Harris. Se observó como positivo un engrosamiento significativo de la capa fibrinoide, degeneración y cambio apoptótico en las células de la decidua, aumento marcado en el área hialinizada, cambios degenerativos en las regiones sincitiales de la vellosidad coriónica y un aumento en los nódulos y puentes sincitiales y la expresión de IL-6. La expresión de FAS fue positiva en los núcleos picnóticos de las células deciduales en la región materna y en las regiones sincitiales. Se observó que el proceso proapoptótico se incrementó como consecuencia de la preeclampsia severa. Se concluyó que el control de la actividad de las citocinas y la reducción de la señal proapoptótica durante el proceso de inflamación ralentizarán el desarrollo del síndrome de HELLP.


Sujets)
Humains , Femelle , Grossesse , Adulte , Jeune adulte , Placenta/immunologie , Interleukine-6/métabolisme , HELLP syndrome/immunologie , Antigènes CD95/métabolisme , Immunohistochimie , Interleukine-6/immunologie , HELLP syndrome/métabolisme , Antigènes CD95/immunologie , Ligand de Fas , Inflammation
2.
Rev. méd. Panamá ; 40(1): 3-8, ene.2020. ilus, tab
Article Dans Espagnol | LILACS-Express | LILACS | ID: biblio-1097382

Résumé

Introducción: Las células madre mesenquimales (MSCs) tienen la capacidad única de auto­renovación y pluripotencia con la cual apoyan en la regeneración de tejidos en or­ ganismos vivos. El mayor potencial terapéutico de las MSCs derivadas de la placenta (PDMSCs) humana, como fuente más joven de MSCs, estimula la búsqueda de las me­ jores condiciones de cultivo que preserven su capacidad de proliferar y diferenciarse. Sin embargo, estudios relacionados a la caracterización de la multipotencialidad de las PDMSCs durante periodos prolongados de cultivo, no han sido reportados en Panamá. Por lo tanto, el objetivo de este estudio fue el de implementar un proceso de aislamiento y cultivo que preserve las propiedades multipotentes en PDMSCs. Materiales y Méto­ dos: Placentas humanas a término completo fueron obtenidas para el aislamiento de las MSCs. Las PDMSCs fueron caracterizadas según su morfología, expresión positiva de marcadores CD90, CD73, CD105, y capacidad de proliferación y diferenciación a linajes mesodérmicos. Resultados: Se ha demostrado la obtención de poblaciones de PDMSCs con morfología fibroblástica, adherencia plástica, expresión positiva de los marcadores CD90, CD73 y CD105, y capacidad de diferenciación osteogénica, adi­ pogénica y condrogénica. Posterior al aislamiento y crio­preservación, las PDMSCs mantuvieron una viabilidad mayor de 95%, una tasa de proliferación por más de 40 días en cultivo, y la expresión positiva de los marcadores CD90, CD73, y CD105 al pasaje 16. Conclusión: Nuestros resultados demuestran una metodología eficiente para obten­ ción y cultivo de PDMSCs que mantienen sus características multipotentes durante períodos prolongados de cultivo, abriendo el camino para futuras terapias celulares


ntroduction: Human mesenchymal stem cells are (MSCs) unique in their pluripotency and their ability to self­renew in order to support tissue regeneration in living organisms. The increased therapeutic potential of PDMSCs as a pool of younger MSCs with a vast capacity for expansion, minor predisposition for tumor formation or immune reactions spurs the search for the best culture conditions to preserve their ability to differentiate and proliferate. However, studies regarding characterization of multipotent isolated PDMSCs during prolonged periods of culture has not been reported thus far in Panama. Therefore, in this study we seek to implement isolation and culture procedures that pre­ serve multipotent characteristics in PDMSCs. Materials and Methods: Full­term human placentas were obtained for the isolation of MSCs. PDMSCs where characterized based on their morphology, positive expression of CD90, CD73, and CD105, and their ability to proliferate and differentiate to mesodermal lineages. Results: It was demonstrated that our isolated PDMSCs presented the MSC characteristics of fibroblastic morphology, plastic adherence, positive expression of CD90, CD73, and CD105 markers, as well as osteogenesis, adipogenesis, and osteogenic differentiation ability. When PDMSCs were cultured after isolation or cryopreservation, viability was maintained above 95%, with their proliferation rate maintained after 40 days, and positive expression of CD90, CD73, and CD105 markers kept after 16 passages. Conclusion: Taken together, our results de­ monstrated a methodology to obtain successful source of isolated human PDMSCs that kept their multipotent properties over time, opening the path for future cellular therapies.


Sujets)
Humains , Femelle , Placenta/immunologie , Médecine régénérative , Cellules souches mésenchymateuses
3.
Rev. chil. infectol ; 36(3): 341-352, jun. 2019. graf
Article Dans Espagnol | LILACS | ID: biblio-1013792

Résumé

Resumen La malaria asociada al embarazo es un evento poco estudiado en América Latina. Los abundantes trabajos sobre el problema en África llevan a pensar que esta infección genera una modulación de la respuesta inmune y alteraciones en el ambiente placentario, eventos cruciales para el adecuado desarrollo del feto y el neonato. La inmunidad contra Plasmodium spp es compleja porque involucra diversos factores que amplían las posibilidades de desenlaces, los que finalmente conducen a los diferentes fenotipos clínicos de la enfermedad. Uno de los desenlaces inmunológicos en infecciones por Plasmodium spp es la modulación de la respuesta inmune hacía un perfil regulador. Esta regulación inducida por la infección malárica resulta ventajosa para la persistencia del parásito en el hospedero, y adicionalmente, podría generar eventos adversos en la respuesta inmune general de los individuos infectados. El objetivo de esta revisión es abordar los mecanismos con los cuales Plasmodium spp modula la respuesta inmune del hospedero y exponer las consecuencias de las infecciones maláricas en el contexto madre-neonato.


Pregnancy-associated malaria is an understudied event in Latin America. Most works about malaria in pregnancy have been conducted in Africa. These studies indicate that the infection generates immune response modulation and alterations in the placental environment, key factors for the proper development of the fetus and neonate. Immunity against Plasmodium spp is complex since involves several factors that increase the possible infection outcomes. One of these immunological outcomes is the immune response modulation towards a regulatory profile, which is advantageous for the persistence of the parasite in the host; additionally, it could generate adverse events in the general immune response of infected individuals. The objective of this review is to address the Plasmodium spp mechanisms of modulation in the host immune response and expose the consequences of malarial infections in the mother-neonate context.


Sujets)
Humains , Femelle , Grossesse , Nouveau-né , Plasmodium/immunologie , Complications parasitaires de la grossesse/immunologie , Immunomodulation/physiologie , Paludisme/immunologie , Placenta/immunologie , Placenta/parasitologie , Plasmodium/physiologie , Interactions hôte-parasite/immunologie , Système immunitaire/immunologie
4.
Clinics ; 71(12): 687-694, Dec. 2016. tab, graf
Article Dans Anglais | LILACS | ID: biblio-840027

Résumé

OBJECTIVE: To investigate the transmission of anti-Staphylococcus aureus (Sa) IgG, IgG1 and IgG2 via placental transfer and the transfer of IgA via the colostrum according to maternal Sa carrier status at delivery. METHODS: We evaluated anti-Sa IgG, IgG1 and IgG2 in maternal and cord sera and IgA in colostrum from a case (n=49, Sa+) and a control group (n=98, Sa-). RESULTS: Of the 250 parturients analyzed for this study, 49 were nasally colonized with S. aureus (prevalence of 19.6%). Ninety-eight non-colonized subjects were selected for the control group. The anti-Sa IgG, IgG1 and IgG2 levels and the IgG avidity indexes in the maternal and cord sera did not differ between the groups, with a low transfer ratio of anti-Sa IgG to the newborns in both groups. The anti-Sa IgG2 titers were significantly higher than the IgG1 titers in the maternal and cord sera. Inversely, the transfer ratios were higher for anti-Sa IgG1 compared with IgG2; however, no differences between the groups were detected. The Sa-specific IgA levels and avidity indexes in the colostrum were equivalent between groups. CONCLUSIONS: Maternal Sa nasal colonization at delivery is not associated with higher antibody levels in the mother or newborns. The high titers of anti-Sa IgG2 found in the cord serum indicate a greater reactivity with non-protein antigens, which may further contribute to the susceptibility to staphylococcal infections at birth. The presence of IgA in the colostrum with avidity to S. aureus reinforces the importance of breastfeeding shortly after birth.


Sujets)
Humains , Femelle , Grossesse , Nouveau-né , Adulte , Placenta/immunologie , Staphylococcus aureus/immunologie , Allaitement naturel , Immunoglobuline G/sang , Immunité acquise d'origine maternelle/immunologie , Anticorps antibactériens/sang , Valeurs de référence , Staphylococcus aureus/isolement et purification , Cordon ombilical/immunologie , Immunoglobuline G/immunologie , Test ELISA , Études transversales , Colostrum/immunologie , Statistique non paramétrique , Anticorps antibactériens/immunologie
5.
Rev. chil. obstet. ginecol ; 79(4): 288-293, 2014. ilus
Article Dans Espagnol | LILACS | ID: lil-724829

Résumé

Los mecanismos fisiopatológicos de la malaria placentaria son hasta el momento poco comprendidos, y el daño placentario derivado de la infección por Plasmodium spp se ha relacionado con eventos adversos del embarazo que afectan directamente el desarrollo del feto. Las concentraciones placentarias de algunas citocinas como la IL-10, TNF-alfa y TGF-beta y glicosaminoglicanos como el CSA, HA y HS podrían estar participando de forma reguladora en los eventos inflamatorios placentarios durante la infección por Plasmodium spp.


The pathophysiological mechanisms of placental malaria are until now poorly understood and the placental damage resulting from infection by Plasmodium spp has been linked to adverse pregnancy events that directly affect fetal development. Placental concentrations of some cytokines such as IL-10, TNF-alpha and TGF-beta and glycosaminoglycans such as CSA, HA and HS could be involved in a regulatory role in placental inflammation during infection by Plasmodium spp.


Sujets)
Humains , Femelle , Grossesse , Glycosaminoglycanes , Paludisme/immunologie , Paludisme/parasitologie , Placenta/immunologie , Placenta/parasitologie , Plasmodium , Complications parasitaires de la grossesse
6.
Pesqui. vet. bras ; 32(5): 396-400, maio 2012. tab
Article Dans Portugais | LILACS | ID: lil-626478

Résumé

O protozoário Nespora caninum é um parasito que causa grandes perdas reprodutivas e econômicas em bovinos no mundo inteiro. Os objetivos deste estudo foram verificar tanto a associação entre o histórico de aborto e a presença de anticorpos contra N. caninum, quanto a transmissão vertical como forma de manutenção da infecção nos rebanhos bovinos em regiões do Rio Grande do Sul, através da sorologia pareada de mães e filhas. Foi realizada amostragem de 60 propriedades distribuídas em duas regiões do Rio Grande do Sul, das quais foi coletado sangue de 40% dos animais presentes para a detecção de anticorpos anti-N. caninum por imunofluorescência indireta (IFI). Para verificar a relação aborto e soropositividade foi utilizado o teste de regressão logística univariada, e para sorologia de mães e filhas o teste de qui-quadrado de McNemar para dados pareados. Foram confrontados os dados de sorologia e aborto, sendo encontrada a frequência de 58,5% (24/41) de soropositivos quando havia histórico de aborto, e 16,4% (199/1215) dentre os sem histórico de aborto. Os animais soropositivos apresentaram um risco 7,21 (IC 95%, 3,65-14,32) vezes maior de possuir histórico de abortamento (estatística de Wald χ2=44,93, P<0,001). A fração atribuível à neosporose como causa de aborto na população em risco nas duas regiões foi estimada em 9,73% (λpop). O resultado sorológico de cada mãe foi pareado com o de sua filha e, pelo teste de qui-quadrado de McNemar (χ2=59,84, P<0,001), houve associação significativa entre as sorologias de mães e filhas, sugerindo transmissão vertical. Ressalta-se ainda a importância do acompanhamento sorológico para N. caninum, evitando assim manutenção de animais portadores que sirvam como reservatório do protozoário nas propriedades.


The protozoa Nesporora caninum is a parasite that causes great economic and reproductive losses in cattle worldwide. The objective of this study was to verify the association between abortion and the presence of antibodies against N. caninum and the vertical transmission as a means of maintaining the infection in cattle herds in Rio Grande do Sul by matching the serology of mothers and daughters. Sampling was performed in 60 dairy farms of two regions of the state, where blood was collected from 40% of the herds for the detection of anti-N. caninum by indirect immunofluorescence (IFI). To verify the association between abortion and seropositivity we used the univariate logistic regression test, and for the serology of mothers and daughters the chi-square McNemar test for paired data. In comparing serology and abortion data, a prevalence of 58.5% (24/41) among cattle with history of abortion, and 16.4% (199/1215) prevalence between those with no history of abortion was found; seropositive animals were 7.21 times more likely (95% CI, 3.65-14.32) to have previously aborted (Wald statistic χ 2=44.93, P<0.001). The fraction affected by neosporosis in the population studied was estimated as 9.73% (λpop). The serologic result of each mother was paired with her daughter and showed by the McNemar chi-square (χ2=59.84, P<0.001) significant association between the serology of mothers and daughters, suggesting vertical transmission. It is worth to note the importance of serological monitoring for N. caninu to avoid maintenance of animals that may serve as carries of the parasite reservoir on the farms.


Sujets)
Animaux , Bovins , Avortement chez les animaux/parasitologie , Neospora/isolement et purification , Échange foetomaternel/génétique , Placenta/immunologie , Sérologie/méthodes
7.
Rev. invest. clín ; 59(2): 139-145, mar.-abr. 2007. ilus
Article Dans Espagnol | LILACS | ID: lil-632368

Résumé

Progesterone is an essential hormone for pregnancy maintenance. This hormone acts by binding to its intracellular receptor or by rapid non-genomic actions to regulate a wide variety of biological functions in the feto-placental unit. Progesterone regulates blastocyst implantation and placental development by inducing immunosupression through type Th2 cytokines secretion. This review summarizes current research about the role of progesterone as critical regulator of expression and secretion of cytokines by T-cell and other placental cells.


La progesterona es una hormona esteroide muy versátil y esencial para el mantenimiento del embarazo. El principal mecanismo de acción de la progesterona es el clásico, vía receptor intracelular, regulando diversas funciones, aspectos celulares y vías moleculares implicadas en el proceso de la implantación. Asimismo existen mecanismos adicionales que no dependen de la interacción del complejo hormona receptor con la maquinaria transcripcional y que son capaces de regular rápidamente cascadas de señalización que determinarán la respuesta de la célula. En particular se ha demostrado que la progesterona ejerce efectos inmunosupresores durante la gestación al favorecer la secreción de citocinas de tipo Th2 por los linfocitos T, evento importante para regular el sistema inmunológico materno y evitar el rechazo de la placenta. El objetivo de esta revisión se centra en analizar la influencia de la progesterona en la interfase materno-fetal sobre la expresión y secreción de citocinas por las células T y no T como es el caso del trofoblasto.


Sujets)
Animaux , Femelle , Souris , Grossesse , Maintien de la grossesse/immunologie , Progestérone/physiologie , Blastocyste , Cytokines/physiologie , Implantation embryonnaire/immunologie , Implantation embryonnaire/physiologie , Régulation de l'expression des gènes , Tolérance immunitaire , Inflammation , Travail obstétrical/physiologie , Lymphocytes/métabolisme , Modèles biologiques , Échange foetomaternel/immunologie , Facteur de transcription NF-kappa B/physiologie , Placenta/croissance et développement , Placenta/immunologie , Maintien de la grossesse/physiologie , Protéines de la grossesse/physiologie , Récepteurs à la progestérone/physiologie , Facteurs suppresseurs immunologiques , Rate/métabolisme
8.
J Health Popul Nutr ; 2001 Jun; 19(2): 59-65
Article Dans Anglais | IMSEAR | ID: sea-794

Résumé

Placental malaria infection jeopardizes pregnancy outcome, and its influence may also impair the transplacental transfer of some antibodies. Two hundred and thirteen Gambian mother-baby pairs were studied to determine the influence of placental malaria infection and maternal hypergammaglobulinaemia on transplacental transfer of measles and tetanus antibodies in Gambian population. Placental blood and tissue were collected for placental malaria diagnosis. Cord and maternal sera were tested for total IgG concentration by laser nephelometry and for IgG antibody to tetanus toxoid and measles by ELISA. The prevalence of placental malaria infection was 51.1%. Mothers whose placentae were parasitized had a significantly higher mean total serum IgG (22.0 g/L vs 11.3 g/L, p < 0.001) and measles antibody level (4.02 IU/mL vs 1.21 IU/mL, p < 0.01), but not tetanus antibody, than mothers with non-parasitized placentae. Results of multiple regression analysis showed that placental malaria infection and maternal hypergammaglobulinaemia were associated with the reduction of 72% (95% CI 67.84) and 86% (95% CI 76.91) in transplacental transfer of measles antibody respectively but did not influence the transfer of tetanus antibody. It is concluded that the combined influence of placental malaria infection and maternal hypergammaglobulinaemia is significantly associated with the transfer of impaired measles antibody in this population.


Sujets)
Adulte , Anticorps/métabolisme , Clostridium tetani/immunologie , Femelle , Sang foetal/immunologie , Humains , Hypergammaglobulinémie/immunologie , Immunité acquise d'origine maternelle , Immunoglobuline G/sang , Transmission verticale de maladie infectieuse , Paludisme/immunologie , Échange foetomaternel , Rougeole/immunologie , Virus de la rougeole/immunologie , Placenta/immunologie , Grossesse , Complications de la grossesse/immunologie , Santé en zone rurale , Tétanos/immunologie , Anatoxine tétanique/immunologie
9.
Indian J Exp Biol ; 1999 Oct; 37(10): 959-64
Article Dans Anglais | IMSEAR | ID: sea-61767

Résumé

Immunosuppressive activity in buffalo placenta was evaluated by measuring proliferation of lymphocytes in presence of phytohaemagglutinin (PHA) alone or PHA plus placental proteins. The immunosuppressive activity was dose-dependent over the protein concentration range of 10-50 micrograms/ml. Proteins from both cotyledon and non-cotyledon portions of placenta exhibited immunosuppressive activity. Fractions obtained with 0-40, 40-60 and 60-80% saturated ammonium sulphate exhibited 70, 73 and 75% suppression, respectively. PBS-soluble placental proteins were resolved on G-100 column into three peaks that exhibited 69 (peak 1), 55 (peak 2) and 73% (peak 3) suppression. Exogenously added interleukin-1 (IL-1) failed to reverse the suppression caused by buffalo placental proteins.


Sujets)
Animaux , Buffles/immunologie , Femelle , Tolérance immunitaire , Interleukine-1/pharmacologie , Activation des lymphocytes , Placenta/immunologie , Grossesse , Protéines de la grossesse/immunologie , Lymphocytes T/immunologie
10.
Rev. Inst. Med. Trop. Säo Paulo ; 41(1): 21-6, Jan.-Feb. 1999. ilus
Article Dans Anglais | LILACS | ID: lil-236721

Résumé

A tecnica de doseamento imunoenzimatico (ELISA) de IgG anti-sarampo (IgG-AS) e a mais pratica e conveniente para estudos com muitos soros. A tecnica de referencia e a reducao de neutralizacao em placa (RNP). Para avaliar a concordancia dos resultados obtidos por ELISA e pela tecnica padrao RNP, comparamos os resultados de doseamentos efetuados pelas duas tecnicas em 43 pares de soros de puerperas e respectivos recem-nascidos (cordao umbilical), e ainda nos soros dessas criancas em amostras colhidas entre os 11 e os 14 meses de idade. Nos soros maternos e do cordao umbilical, as diferencas medias das concentracoes de IgG-AS medidas por ELISA ou RNP nao eram estatisticamente significativas. No entanto, a nivel individual as diferencas eram por vezes grandes. A concordancia nao era tao boa no caso dos soros infantis, nos quais os niveis de anticorpos residuais eram muito baixos...


Sujets)
Humains , Mâle , Femelle , Nouveau-né , Techniques immunoenzymatiques , Vaccin contre la rougeole , Normes de référence , Test ELISA , Immunoglobuline G/analyse , Immunoglobuline G/immunologie , Tests de neutralisation , Placenta/immunologie , Tests sérologiques
11.
Indian Pediatr ; 1998 Dec; 35(12): 1187-91
Article Dans Anglais | IMSEAR | ID: sea-13599

Résumé

OBJECTIVE: To find out the patterns of and the factors, if any, affecting the transplacental transfer of measles antibody. DESIGN: Comparison of measles antibody titres in mothers with titres in cord blood samples. METHODS: Maternal and cord blood samples from 174 full-term pregnant women of middle socio-economic status were tested for hemagglutination inhibition (HI) antibody against measles in Delhi during October 1993 to January 1995. None of the mothers had been immunized against measles. RESULTS: Antibody were undetectable in both maternal and cord samples in only 4 (2.3%) pairs. Mean maternal titre was found to be 2.94 Log2. Transplacental concentration and dilution were respectively observed in 34% and 26% of the samples. Cord titres were more often higher than the maternal values only if the maternal values were low. Overall, cord/maternal ratio of mean titre (Log2) was found to be 1.06. Although the age of the mother and parity had had no significant bearing on the transplacental transfer of measles antibody, cord titres were significantly more often higher than the maternal values as the birth weight increased (Chi-square for linear trend = 5.4; p = 0.02). CONCLUSIONS: The study failed to show appreciable concentration of measles antibodies across the placenta.


Sujets)
Adolescent , Adulte , Anticorps antiviraux/sang , Poids de naissance , Loi du khi-deux , Femelle , Sang foetal/immunologie , Hémagglutination virale/immunologie , Humains , Immunité acquise d'origine maternelle/immunologie , Inde , Nouveau-né , Modèles linéaires , Âge maternel , Virus de la rougeole/immunologie , Parité , Placenta/immunologie , Grossesse/sang , Classe sociale
13.
Braz. j. med. biol. res ; 29(2): 201-4, Feb. 1996. graf
Article Dans Anglais | LILACS | ID: lil-161670

Résumé

In order to study placental transfer of IgG subclasses, paired blood samples were collected from mothers and umbilical cord of preterm (N = 69) and full-term (N = 68) newborns. The full-term group was further divided into 3 subgroups: appropriate for gestational age (AGA, N = 43), large for gestational age (LGA, N = 13) and small for gestational age (SGA, N = 12), according to birth weight. IgG subclasses (IgG1, IgG2, IgG3 and IgG4) were measured by the single radial immunodiffusion technique using monoclonal antibodies. IgG1 and IgG3 newborn subclass concentrations (10.17 and 0.57 g/l, respectively) increased with increasing gestational age and reached maternal levels (IgG1 = 8.86; IgG3 = 0.67 g/l) during the 37th week of pregnancy. Low levels of these subclasses were found in premature newborns. IgG2 from newborns were always lower than maternal levels (P<0.05). LGA and SGA newborns had equivalent levels of IgG1 and IgG2 compared with AGA. SGA newborns had higher levels of IgG3 and lower levels of IgG4 than LGA and AGA newborns.


Sujets)
Humains , Femelle , Grossesse , Nouveau-né , Immunisation passive , Immunoglobuline G/sang , Prématuré/sang , Placenta/physiologie , Nouveau-né/sang , Immunoglobuline G/classification , Placenta/immunologie , Récepteur Fc
14.
In. Montenegro Medina, María Angélica; Mena L., Miguel Angel; Illanes Herrero, Julio; Lemus Acuña, David. Embriología humana. Santiago de Chile, Universidad de Chile. Facultad de Medicina. Departamento de Morfología Experimental, 1996. p.89-107, ilus.
Monographie Dans Espagnol | LILACS | ID: lil-185317
15.
Acta bioquím. clín. latinoam ; 29(2): 191-6, jun. 1995. ilus
Article Dans Espagnol | LILACS | ID: lil-157485

Résumé

En este trabajo se investiga la acción del medio condicionado de placenta humana (MCPH) sobre linfocitos periféricos in vitro. Se cultivaron leucocitos periféricos de varones, mujeres con diferente número de partos, gestantes y nulíparas, en su propio plasma sin y con MCPH al 5, 10 y 20 por ciento. Luego de 120 h de cultivo se determinó la Transformación Blástica Linfocitaria (TBL, valores ò 0,5 indican estimulación) por observación de la morfología celular. Los linfocitos de varones y mujeres nulíparas no responden a ninguna de las concentraciones de MCPH ensayadas. En mujeres que han tenido hijos, la más alta transformación blástica linfocitaria se observa con MCPH al 10 por ciento, siendo esta respuesta correlativa con el número de partos (r = 0,73). En gestantes, si bien la máxima respuesta se obtiene con MCPH al 10 por ciento, el agregado de 5 por ciento del extracto es suficiente para producir estimulación linfocitaria (TBL x = 0,54 ñ 0,05). En conclusión, MCPH al 10 por ciento sigue siendo la concentración óptima para provocar blastogénesis linfocitaria. Además, en el plasma de las mujeres gestantes existirían sustancias que potencian la acción del extracto in vitro, permitiendo TBL > 0,5 con la adición de sólo 5 por ciento de MCPH


Sujets)
Humains , Mâle , Femelle , Grossesse , Milieux de culture conditionnés/pharmacocinétique , Tolérance immunitaire , Techniques in vitro , Échange foetomaternel/immunologie , Placenta/immunologie , Activation des lymphocytes , Placenta/physiologie
16.
Indian J Pediatr ; 1989 Mar-Apr; 56(2): 181-7
Article Dans Anglais | IMSEAR | ID: sea-80671

Résumé

The neuroendocrine system helps in the success of the fetal graft by suppressing maternal cellular immune response against the foreign paternal histocompatibility (HLA) antigens. In addition, placenta absorbs the antibodies directed against the paternal HLA antigens, thus inhibiting the humoral rejection of the fetal graft. In contrast, neuropeptides released in the maternal blood stream under adverse mental states may stimulate lymphocyte blastogenesis and natural killer (NK) cell activity resulting in premature loss of the fetus. Further, homozygosity of a lethal gene which is in linkage disequilibrium with HLA genes may have a role in some unexplained fetal deaths.


Sujets)
Femelle , Gènes létaux , Hormones sexuelles stéroïdiennes/immunologie , Humains , Tolérance immunitaire/immunologie , Système neuroendocrinien/immunologie , Placenta/immunologie , Hormones placentaires/immunologie , Grossesse/immunologie , Complications de la grossesse/immunologie
20.
Biomédica (Bogotá) ; 2(2): 63-72, abr. 1982. ilus
Article Dans Espagnol | LILACS | ID: lil-81302

Résumé

Mediante el uso de los metodos de peroxidasa anti-peroxidasa e inmunofluorescencia aplicada a tejidos desparafinados y tratados con tripsina, se estudiaron inmunocitoquimicamente un grupo de placentas y tumores malignos. Al utilizar anticuerpos anti-GCH, la hormona gonadotropina corionica humana (GCH) fue localizada en celulas del sincitiotrofoblasto de plancetas de diferentes estados de desarrollo, se encontro ademas, que las celulas de Langhan's y del citotrofoblasto fueron negativas a la inmuno-reaccion. La mayoria de los tumores estudiados fueron encontrados positivos al aplicar los metodos mencionados. Se postula que la inmunosupresion selectiva del huesped por tumores y la inmunosupresion selectiva de tejidos maternos por tejidos fetales, podria estar mediada por la hormona gonadotropina corionica


Sujets)
Humains , Gonadotrophine chorionique/analyse , Techniques immunoenzymatiques , Tumeurs/immunologie , Tumeurs/ultrastructure , Placenta/immunologie , Placenta/ultrastructure
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