Molecular mechanisms involved in cell response to mechanical forces

New devices were designed to generate a localized mechanical vibration of flexible gels where human umbilical vein endothelial cells (HUVECs) were cultured. The stimulation setups were able to apply relatively large strains (30%~50%) at high temporal frequencies (140~207 Hz) in a localized subcellular region. One of the advantages of this technique was to be less invasive to the innate cellular functions because there was no direct contact between the stimulating probe and the cell body. A mechanical vibration induced by the device in the substrate gel where cells were seeded could mainly cause global calcium responses of the cells. This global response was initiated by the influx of calcium across the stretch-activated channels in the plasma membrane. The subsequent production of inositol triphosphate (IP3) via phospholipase C (PLC) activation triggered the calcium release from the endoplasmic reticulum (ER) to cause a global intracellular calcium fluctuation over the whole cell body. This global calcium response was also shown to depend on actomyosin contractility and F-actin integrity, probably controlling the membrane stretch-activated channels. The localized nature of the stimulation is one of the most important features of these new designs as it allowed the observation of the calcium signaling propagation by ER calcium release. The next step was to focus on the calcium influx, more specifically the TRPM7 channels. As TRPM7 expression may modulate cell adhesion, an adhesion assay was developed and tested on HUVECs seeded on gel substrates with different treatments: normal treatment on gels showed highest attachment rate, followed by the partially treated gels (only 5% of usual fibronectin amount) and untreated gels, with the lowest attachment rate. The trend of the attachment rates correlated to the magnitude of the calcium signaling observed after mechanical stimulation. TRPM7 expression inhibition by siRNA caused an increased attachment rate when compared to both control and non-targeting siRNA-treated cells, but resulted in an actual weaker response in terms of calcium signaling. It suggests that TRPM7 channels are indeed important for the calcium signaling in response to mechanical stimulation. A complementary study was also conducted consisting in the mechanical stimulation of a dissected Drosophila embryo. Although ionomycin treatment showed calcium influx in the tissue, the mechanical stimulation delivered as a vertical vibration did not elicited calcium signaling in response. One possible reason is the dissection procedure causing desensitization of the tissue due to the scrapings and manipulations to open the embryo.

Fissura placentária de gatas SRD, Felis catus - Linnaeus, 1758: aspectos macro e microscópicos

Nossa pesquisa consiste no estudo esquemático macroscópico na placenta de gatos e a sua caracterização como tipo, placenta zonária, que 62,5% dos casos apresenta uma fissura na área distal do funículo umbilical. Esse é formado por uma área justa fetal, área justa placentária e área média, encontrando achados histológicos de 2 artérias, uma veia, 2 pedículos vitelínicos e 2 pedículos alantoidianos. Na fissura, encontramos um epitélio alantoidiano cobrindo esta área em 10% dos casos e, em 90% dos achados foram encontrados um trofoblasto diminuído comparado com outras áreas placentárias fora da fissura. Portanto, a placenta felina, com sua relação materno fetal mostra uma placenta zonária incompleta, diferente do ocorrido nos outros carnívoros.

Resultado perinatal de embarazos a término con oligohidramnios de moderado a severo que consultan en el Hospital Nacional de Maternidad “Dr. Raúl Arguello Escolán” entre el período de Enero a Diciembre de 2013

La disminución del líquido amniótico se asocia con un incremento de la morbimortalidad del recién nacido. La principal consecuencia descrita por la literatura es una mayor compresión sobre el abdomen fetal, lo que conlleva a una disminución en el movimiento del diafragma fetal, que puede desencadenar una limitación en el desarrollo del tejido funcional pulmonar conllevando problemas en la transición respiratoria en la vida extrauterina del infante. El oligohidramnios como condición que complica el embarazo se observa en el 3 al 5 % del total de los embarazos. El líquido amniótico es esencial para el crecimiento y desarrollo del feto. El líquido protege al feto de infecciones, traumatismos, compresión del cordón umbilical y facilita los movimientos fetales. El volúmen de líquido amniótico es un indicador importante utilizado frecuentemente en el control prenatal debido a que ciertas alteraciones de líquido amniótico se asocian con un pobre pronóstico del embarazo, ya que pueden mostrarnos defectos anatómicos en el riñón fetal que pueden conllevar múltiples malformaciones. En la actualidad, en la mayoría de centros perinatales de América se utiliza el índice de líquido amniótico como parte de una de las pruebas de bienestar fetal. En el Hospital de Maternidad el oligohidramnios es una patología muy frecuente de causa de consulta en unidad de emergencia y consulta externa, así como de ingreso hospitalario. Con el presente trabajo se dio a conocer el resultado perinatal de las pacientes que presentaron oligohidramnios durante el embarazo que consultaron el Hospital Nacional de Maternidad, así como también se describe la presencia de factores de riesgo socioeconómicos como la edad, escolaridad y estado civil que puedan presentarse en ésta patología. También se describe cual ha sido la vía de evacuación más frecuente en éstos casos, así como también el resultado perinatal de los recién nacidos con ésta patología la cual se presentó durante el embarazo.

Endometrial tuberculosis simulating an ovarian cancer

Female genital tuberculosis remains a major health problem in developing countries and is an important cause of infertility. As symptoms, laboratory data and physical fndings are non-specifc, its diagnosis can be diffcult. We describe a case of a 39-year-old woman suffering from peri-umbilical pain and increased abdominal size for one year, anorexia, asthenia, weight loss, occasionally dysuria and dyspareunia, and four months amenorrhea. Laboratory data revealed cancer antigen 125 (CA-125) level of 132.3 U/mL, erythrocyte sedimentation rate of 42 mm/h, and gamma-globulins of 2.66 g/dL. Computer Tomography scan showed loculated ascites. It was initially suspected a carcinomatous origin, but ascites evaluation was negative for malignant cells. Magnetic Resonance Imaging from another hospital showed endometrial heterogeneity. Therefore, an endometrial biopsy was performed demonstrating an infammatory infltrate with giant cells of type Langhans and bacteriological culture identifed Mycobacterium tuberculosis

Update on imaging of ovarian cancer

This review will make familiar with new concepts in ovarian cancer and their impact on radiological practice. Disseminated peritoneal spread and ascites are typical of the most common (70–80 %) cancer type, highgrade serous ovarian cancer. Other cancer subtypes differ in origin, precursors, and imaging features. Expert sonography allows excellent risk assessment in adnexal masses. Owing to its high specificity, complementary MRI improves characterization of indeterminate lesions. Major changes in the new FIGO staging classification include fusion of fallopian tube and primary ovarian cancer and the subcategory stage IIIA1 for retroperitoneal lymph node metastases only. Inguinal lymph nodes, cardiophrenic lymph nodes, and umbilical metastases are classified as distant metastases (stage IVB). In multidisciplinary conferences (MDC), CT has been used to predict the success of cytoreductive surgery. Resectability criteria have to be specified and agreed on in MDC. Limitations in detection of metastases may be overcome using advanced MRI techniques.

Efficacy of early skin-to-skin contact on the rate of exclusive breastfeeding in term neonates: a randomized controlled trial

Background: Despite multiple benefits of breast milk, the rates of exclusive breastfeeding in developing countries are low. Objective: To evaluate the efficacy of early skin -to -skin contact (SSC) on the rate of exclusive breastfeeding (EBF) at 6 weeks of age among term neonates born by vaginal delivery. Methods: Term neonates born by vaginal delivery and did not require any resuscitation were randomized at birth to SSC (n=100) and control (n=100) group. Immediately after clamping the umbilical cord, SSC group neonates were placed on the bare bosom of mother and control group neonates were placed under a radiant warmer for a period of 45 minutes each while mothers underwent management of the third stage of labor and episiotomy repair. Pain experienced by mother during episiotomy repair was recorded using a numerical pain scale The primary outcome evaluated was the rate of exclusive breastfeeding at 6 weeks of postnatal age. Results: A significantly higher proportion of neonates were exclusively breastfeed at 6 weeks of age in the SSC group than in the control group (72% vs. 57.6%, p=0.04, relative risk: 1.3, 95% confidence interval: 1.0 -1.6). The pain score during episiotomy repair in mothers of the SSC group was significantly lower than the control group (4.74±0.85 versus 5.34±0.81; P <0.01). Conclusions: Early SSC significantly improved the rate of exclusively breastfeeding at 6 weeks of age among healthy term neonates. An important additional effect was a decrease in the amount of pain that mothers in the SSC group experienced during episiotomy repair.

Análise da estabilidade genética de células-tronco mesenquimais humanas

Human multipotent mesenchymal stromal cells (MSCs), also known as mesenchymal stem cells, have become an important and attractive therapeutic tool since they are easily isolated and cultured, have in vitro expansion potential, substantial plasticity and secrete bioactive molecules that exert trophic effects. The human umbilical cord as a cell source for cell therapy will help to avoid several ethical, political, religious and technical issues. One of the main issues with SC lines from different sources, mainly those of embryonic origin, is the possibility of chromosomal alterations and genomic instability during in vitro expansion. Cells isolated from one umbilical cord exhibited a rare balanced paracentric inversion, likely a cytogenetic constitutional alteration, karyotype: 46,XY,inv(3)(p13p25~26). Important genes related to cancer predisposition and others involved in DNA repair are located in 3p25~26. Titanium is an excellent biomaterial for bone-implant integration; however, the use can result in the generation of particulate debris that can accumulate in the tissues adjacent to the prosthesis, in the local bone marrow, in the lymph nodes, liver and spleen. Subsequently may elicit important biological responses that aren´t well studied. In this work, we have studied the genetic stability of MSC isolated from the umbilical cord vein during in vitro expansion, after the cryopreservation, and under different concentrations and time of exposition to titanium microparticles. Cells were isolated, in vitro expanded, demonstrated capacity for osteogenic, adipogenic and chondrogenic differentiation and were evaluated using flow cytometry, so they met the minimum requirements for characterization as MSCs. The cells were expanded under different concentrations and time of exposition to titanium microparticles. The genetic stability of MSCs was assessed by cytogenetic analysis, fluorescence in situ hybridization (FISH) and analysis of micronucleus and other nuclear alterations (CBMN). The cells were able to internalize the titanium microparticles, but MSCs preserve their morphology, differentiation capacity and surface marker expression profiles. Furthermore, there was an increase in the genomic instability after long time of in vitro expansion, and this instability was greater when cells were exposed to high doses of titanium microparticles that induced oxidative stress. It is necessary always assess the risks/ benefits of using titanium in tissue therapy involving MSCs, considering the biosafety of the use of bone regeneration using titanium and MSCs. Even without using titanium, it is important that the therapeutic use of such cells is based on analyzes that ensure quality, security and cellular stability, with the standardization of quality control programs appropriate. In conclusion, it is suggested that cytogenetic analysis, FISH analysis and the micronucleus and other nuclear alterations are carried out in CTMH before implanting in a patient

Transcriptoma diferencial entre células-tronco mesenquimais humanas jovens e senescentes

Human mesenchymal stem cells (MSC) are powerful sources for cell therapy in regenerative medicine. The long time cultivation can result in replicative senescence or can be related to the emergence of chromosomal alterations responsible for the acquisition of tumorigenesis features in vitro. In this study, for the first time, the expression profile of MSC with a paracentric chromosomal inversion (MSC/inv) was compared to normal karyotype (MSC/n) in early and late passages. Furthermore, we compared the transcriptome of each MSC in early passages with late passages. MSC used in this study were obtained from the umbilical vein of three donors, two MSC/n and one MSC/inv. After their cryopreservation, they have been expanded in vitro until reached senescence. Total RNA was extracted using the RNeasy mini kit (Qiagen) and marked with the GeneChip ® 3 IVT Express Kit (Affymetrix Inc.). Subsequently, the fragmented aRNA was hybridized on the microarranjo Affymetrix Human Genome U133 Plus 2.0 arrays (Affymetrix Inc.). The statistical analysis of differential gene expression was performed between groups MSC by the Partek Genomic Suite software, version 6.4 (Partek Inc.). Was considered statistically significant differences in expression to p-value Bonferroni correction ˂.01. Only signals with fold change ˃ 3.0 were included in the list of differentially expressed. Differences in gene expression data obtained from microarrays were confirmed by Real Time RT-PCR. For the interpretation of biological expression data were used: IPA (Ingenuity Systems) for analysis enrichment functions, the STRING 9.0 for construction of network interactions; Cytoscape 2.8 to the network visualization and analysis bottlenecks with the aid of the GraphPad Prism 5.0 software. BiNGO Cytoscape pluggin was used to access overrepresentation of Gene Ontology categories in Biological Networks. The comparison between senescent and young at each group of MSC has shown that there is a difference in the expression parttern, being higher in the senescent MSC/inv group. The results also showed difference in expression profiles between the MSC/inv versus MSC/n, being greater when they are senescent. New networks were identified for genes related to the response of two of MSC over cultivation time. Were also identified genes that can coordinate functional categories over represented at networks, such as CXCL12, SFRP1, xvi EGF, SPP1, MMP1 e THBS1. The biological interpretation of these data suggests that the population of MSC/inv has different constitutional characteristics, related to their potential for differentiation, proliferation and response to stimuli, responsible for a distinct process of replicative senescence in MSC/inv compared to MSC/n. The genes identified in this study are candidates for biomarkers of cellular senescence in MSC, but their functional relevance in this process should be evaluated in additional in vitro and/or in vivo assays

Étude de la reconstitution de l’immunité spécifique au cytomégalovirus et au virus de la varicelle suite à la transplantation de sang de cordon ombilical

La transplantation de sang de cordon ombilical (TSCO) constitue un traitement de choix pour une multitude de pathologies hématologiques malignes et non malignes chez l’enfant et dans certains cas l’adulte. La TSCO est associée à certaines complications, dont une reconstitution immunitaire plus lente et une incidence élevée d’infections opportunistes, notamment celles reliées au cytomégalovirus (CMV) et au virus varicella-zoster (VZV). Dans le cadre de ce travail, nous nous sommes intéressés dans un premier temps à la caractérisation de la reconstitution immunitaire spécifique au CMV et au VZV. Nos résultats ont démontré que la reconstitution de l’immunité cellulaire ne requiert ni un statut séropositif pré-transplantation ni le développement de la maladie. De plus, des reconstitutions spontanées ont été détectées chez certains patients séronégatifs vis-à-vis du CMV ou du VZV. Outre le fait qu’elle se manifeste surtout à partir de 6 mois post-transplantation, ladite reconstitution mérite le qualificatif de « protectrice » en termes de réactivations virales et du développement de signes cliniques lorsqu’une fréquence de 150 cellules produisant l’IFN-γ/million est dépassée. Toutefois, moins de 5% des patients développent une réponse T anti-VZV et anti-CMV au cours 100 premiers jours suivant la TSCO. Il est donc possible que les lymphocytes CD8+ T provenant du SCO, comparativement à leurs homologues provenant de la moelle osseuse (MO), présentent un défaut de fonctionnalité, communément appelé « épuisement clonal ». La caractérisation du répertoire de récepteurs inhibiteurs exprimés par les cellules T CD8+ suivant la TSCO ou la transplantation de moelle osseuse (TMO) a révélé une augmentation significative de la fréquence des cellules exprimant PD-1 tôt suivant la transplantation. Cette population, caractérisée majoritairement par un phénotype effecteur-mémoire (EM), démontre une perte significative de la capacité proliférative et exprime moins d'IFN-γ, d'IL-2, de TNF-α et de CD107a. Une meilleure caractérisation de la reconstitution immunitaire après TSCO permettrait, d'une part de sélectionner des biomarqueurs en vue d’une meilleure gestion des patients à risques de développer des infections virales et/ou de rechuter, et d'autre part d'améliorer leur pronostic.

Prevención de hemorragia postparto con misoprostol bucal transcesárea en pacientes con riesgo de atonía uterina

Antecedentes: La causa más frecuente de muerte materna es la hemorragia obstétrica por atonía uterina. Aun con manejo activo del tercer periodo del parto con oxitocina, casi la mitad de las pacientes necesitará fármacos adicionales para controlar la hemorragia durante la cesárea. Objetivo: Demostrar que la administración de Misoprostol bucal durante la cesárea disminuye la utilización de fármacos uterotónicos adicionales y previene la hemorragia obstétrica. Material y métodos: Ensayo clínico aleatorizado doble ciego en el que se estudiaron 120 mujeres con factores de riesgo de atonía uterina a quienes se realizó cesárea bajo bloqueo epidural. Fueron asignadas aleatoriamente a dos grupos: el grupo experimental fue tratado con 400 mcg de Misoprostol y el grupo placebo con 800 mcg de ácido fólico. Ambos grupos recibieron el tratamiento vía bucal después del pinzamiento del cordón umbilical además de infusión de oxitocina. Las variables a estudiar fueron el requerimiento de fármacos uterotónicos adicionales y el diagnóstico de hemorragia obstétrica. Resultados: Más mujeres en el grupo placebo requirieron al menos un fármaco uterotónico adicional. (40% y 10%, RR 0.16, IC 95%, 0.06-0.44, p=0.01). La incidencia de hemorragia obstétrica fue mayor el grupo placebo (20% y 5%, RR 0.21, IC 95% 0.05-0.79, p=0.025) al igual que la incidencia de atonía uterina (25% y 8.3%, RR 0.27, IC 95% 0.09-0.80, p=0.026). Conclusión: La aplicación de Misoprostol en el espacio bucal durante la cesárea disminuyó la necesidad de utilizar fármacos uterotónicos adicionales para tratar atonía uterina y la incidencia de hemorragia obstétrica.

Relationship between waist circumference and sagittal abdominal diameter measured at different anatomical sites and inflammatory biomarkers in apparently health men

Introduction: Visceral fat accumulation is associated with several changes, such as, increased production of inflammatory biomarkers, especially, C-reactive protein (CRP) and fibrinogen. Anthropometric measurements for central adiposity evaluation, such as, waist circumference (WC) and sagittal abdominal diameter (SAD) have been highlighted. However, there is no consensus on the best anatomical site for measurement. Objective: To evaluate the reliability of different measurements of WC and SAD and verify their capacity to discriminate changes in inflammatory biomarkers. Method: 130 men (20-59 years) were assessed, having measurements of weight, height, WC and SAD. It was considered as the cutoff point for high-sensitivity CRP (hs-CRP) values ≥ 0.12 mg/dL and for fibrinogen the 50th percentile of the evaluated sample. Results: All measurements presented an intraclass correlation coefficient between 0.998 and 0.999. WC measured at the umbilical level (AUC=0.693±0.049) and the smallest circumference between the thorax and the hips (AUC=0.607±0.050) had greater ability to discriminate changes in concentrations of hs-CRP and fibrinogen, respectively. SAD (umbilical level) showed the better ability to detect changes in concentrations of hs-CRP (AUC=0.698± 0.049) and fibrinogen (AUC=0.625±0.049), according to the ROC analysis (p<0.05). Conclusion: WC (smallest circumference between the thorax and the hips) and SAD (umbilical level) are the anatomic sites of measurement for use in predicting the inflammatory risk in apparently health men.

Risk Factors for Neonatal Sepsis and Method for Reduction of Blood Culture Contamination

Background False-positive blood cultures findings may lead to a falsely increased morbidity and increased hospital costs. Method The survey was conducted as retrospective - prospective study and included 239 preterm infants (born before 37 weeks of gestation) who were treated in Neonatal Intensive Care Unit (NICU) in Institute for Child and Youth Health Care of Vojvodina during one year (January 1st, 2012 to December 31st, 2012). The retrospective part of the study focused on examination of incidence of neonatal sepsis and determination of risk factors. In the prospective part of the study infants were sub-divided into two groups: Group 1- infants hospitalized in NICU during the first 6 months of the study; blood cultures were taken by the ‘’clean technique’’ and checklists for this procedure were not taken. Group 2- neonates hospitalized in NICU during last 6 months of the study; blood cultures were taken by ‘’sterile technique’’ and checklists for this procedure were taken. Results The main risk factors for sepsis were prelabor rupture of membranes, low gestational age, low birth weight, mechanical ventilation, umbilical venous catheter placement, and abdominal drainage. Staphylococcus aureus and coagulase negative Staphylococcus were the most frequently isolated microorganisms in false-positive blood samples. Conclusions Education of employees, use of checklists and sterile sets for blood sampling, permanent control of false positive blood cultures, as well as regular and routine monthly reports are crucial for successful reduction of contamination rates.

Pauta de colocación de catéteres umbilicales

Dada la necesidad y la relevancia de la utilización de este abordaje para la colocación de vías centrales en recién nacidos, proponemos una pauta de colocación de catéteres umbilicales para realizar en los servicios de recién nacidos. Destacamos los casos en que está contraindicada la colocación de los mismos. El cateterismo umbilical es una maniobra rápida para el acceso venoso y arterial, y es segura si se cumple con las pautas recomendadas y se mantienen los cuidados adecuados en su colocación y mantenimiento, utilizando el material sugerido para realizar la maniobra y para el peso del niño. Se debe evitar manipular para realizar modificaciones en su posición por la aparición de sangrados y el riesgo de infección, esto prácticamente desaparece si se respetan las reglas de distancias de introducción de catéter, así como la realización de jaretas o puntos de seguridad. De esta manera también se evita la migración con eventual salida y pérdida de la vía. Las complicaciones más frecuentes del uso de catéteres, tanto venosos como arteriales, son el sangrado y la infección. Destacamos la importancia de retirar los mismos una vez obtenida una vía alternativa.

La conservation autologue de sang de cordon ombilical : une ouverture sur une forme émergente de «citoyenneté biologique»

La transformation du sang de cordon ombilical en une précieuse source de cellules souches a, dès le début des années 1990, donné naissance à une industrie commerciale globale de conservation faisant désormais concurrence à un large réseau de conservation public. Ce mémoire cherche à comprendre et à expliquer les soubassements socio-culturels liés à l’émergence de cette industrie, ainsi qu’à mieux cerner les enjeux éthiques et politiques qu’elle pose. En exposant en premier lieu la manière dont les institutions publiques de conservation de sang de cordon se définissent, et sont généralement définies par les comités bioéthiques, comme étant porteuses des valeurs d’altruisme et de solidarité nationale traditionnellement liées au modèle « redistributif » d’échange de sang et d’organes né au lendemain de la Seconde Guerre mondiale, nous problématisons la manière innovatrice par laquelle les banques privées structurent le rapport entre les mères et leurs propres produits biologiques comme l’expression d’une reconfiguration du lien social et politique caractérisée par l’émergence de nouvelles socialisés. L’hypothèse au coeur de ce mémoire est que celles-ci peuvent être comprises comme l’aboutissant de l‘espoir collectivement partagé par les consommatrices d’améliorer leur propre condition biologique familiale, étant lui-même le fruit d’une financiarisation croissante des sciences du vivant. En analysant le discours « promissif » que représente le matériel promotionnel des banques autologues, notre objectif est alors d’identifier la manière par laquelle les multiples potentialités attribuées au sang de cordon définissent des subjectivités maternelles caractérisées par des obligations morales spécifiques.

Anomalies immunitaires chez les enfants exposés au VIH mais non infectés.

La thérapie antirétrovirale prévient la transmission mère-enfant du VIH dans plus de 98% des cas lorsqu’administrée pendant la grossesse, le travail et au nouveau-né. L’accessibilité à la thérapie antirétrovirale dans près de 70% des 1,5 millions cas de grossesses VIH+ dans le monde mène à la naissance de plus d’un million d’enfants exposés non infectés chaque année. Le nombre d’enfants exposés non infectés est à la hausse ainsi que les préoccupations concernant leur santé. En effet, plusieurs groupes ont signalé une augmentation de la morbidité et de la mortalité chez les enfants exposés non infectés. L’analyse des données rétrospectives de 705 enfants exposés non infectés de la cohorte mère-enfant du CMIS a révélé qu’à 2 mois d’âge, les enfants nés de mères ayant une charge virale supérieure à 1,000 copies d’ARN / ml avaient une fréquence de lymphocytes B significativement plus élevés par rapport aux enfants exposés non infectés nés de mères ayant une charge virale indétectable. L’objectif de cette étude est de caractériser ces anomalies. Les lymphocytes, provenant du sang de cordon ombilical et de sang veineux obtenu à 6 et 12 mois d’âge, ont été phénotypés par cytométrie en flux à l’aide des marqueurs CD3 / CD10 / CD14 / CD16 / CD19 / CD20 / CD21 / CD27 / IgM pour les lymphocytes B et CD4 / CD8 / CD3 / CCR7 / CD45RA pour les lymphocytes T. De plus, afin d’étudier les capacités fonctionnelles des lymphocytes B CD19+, la réponse antigène-spécifique au vaccin antitétanique a été mesurée par marquage avec des tétramères fluorescents de fragment C du toxoïde tétanique. Nos travaux ont mis en évidence des différences statistiquement significatives entre les enfants exposés non-infectés (ENI) nés de mères avec une charge virale détectable comparativement à ceux nés de mères avec une charge virale indétectable. À la naissance, les enfants ENI nés de mères avec une charge virale détectable avaient significativement moins de lymphocytes B totaux, plus de lymphocytes B mémoires classiques, activés, plasmablastes et lymphocytes T CD8+ mémoires centrales. À 6 mois, ils avaient significativement plus de lymphocytes B naïfs et significativement moins de lymphocytes T CD8+ effecteurs mémoires. À 12 mois d’âge, ils avaient significativement plus de lymphocytes B et T CD8+ totaux; significativement moins de lymphocytes T CD4+ totaux et leurs lymphocytes T affichaient un profil significativement plus activé (plus de cellules mémoires). L’analyse de la réponse antigène-spécifique a révélé une fréquence plus élevé de lymphocytes B mémoires IgM+ suggérant que les enfants nés de mères avec une virémie détectable ont plus de mal à établir une mémoire immunitaire efficace face au vaccin antitétanique. Nos données suggèrent qu’il y a exposition durant le premier trimestre de grossesse à la virémie maternelle et que cette exposition impacte le système immunitaire en développement du fœtus. Les mécanismes sous-jacents causant ces anomalies doivent encore être élucidés et l’épuisement du compartiment T à la naissance et à 6 mois reste à être investigué. Dans un pays industrialisé où l’accès aux soins est facilité, ces anomalies ont des conséquences modérées mais dans des pays à faible et moyen revenu, les conséquences peuvent être beaucoup plus tragiques voir fatales.