Ronit Gilad

Inhibitory NK receptor recognition of HLA-G: regulation by contact residues and by cell specific expression at the fetal-maternal interface.

The non-classical HLA-G protein is distinguished from the classical MHC class I molecules by its expression pattern, low polymorphism and its ability to form complexes on the cell surface. The special role of HLA-G in the maternal-fetal interface has been attributed to its ability to interact with specific receptors found on maternal immune cells. However this interaction is restricted to a limited number of receptors. In this study we elucidate the reason for this phenomenon by comparing the specific contact residues responsible for MHC-KIR interactions. This alignment revealed a marked difference between the HLA-G molecule and other MHC class I molecules. By mutating these residues to the equivalent classical MHC residues, the HLA-G molecule regained an ability of interacting with KIR inhibitory receptors found on NK cells derived either from peripheral blood or from the decidua. Functional NK killing assays further substantiated the binding results. Furthermore, double immunofluorescent staining of placental sections revealed that while the conformed form of HLA-G was expressed in all extravillous trophoblasts, the free heavy chain form of HLA-G was expressed in more distal cells of the column, the invasion front. Overall we suggest that HLA-G protein evolved to interact with only some of the NK inhibitory receptors thus allowing a control of inhibition, while permitting appropriate NK cell cytokine and growth factor production necessary for a viable maternal fetal interface.

Modeling of Human Cytomegalovirus Maternal-Fetal Transmission in a Novel Decidual Organ Culture

ABSTRACT Human cytomegalovirus (HCMV) is the leading cause of congenital infection, associated with severe birth defects and intrauterine growth retardation. The mechanism of HCMV transmission via the maternal-fetal interface is largely unknown, and there are no animal models for HCMV. The initial stages of infection are believed to occur in the maternal decidua. Here we employed a novel decidual organ culture, using both clinically derived and laboratory-derived viral strains, for the ex vivo modeling of HCMV transmission in the maternal-fetal interface. Viral spread in the tissue was demonstrated by the progression of infected-cell foci, with a 1.3- to 2-log increase in HCMV DNA and RNA levels between days 2 and 9 postinfection, the expression of immediate-early and late proteins, the appearance of typical histopathological features of natural infection, and dose-dependent inhibition of infection by ganciclovir and acyclovir. HCMV infected a wide range of cells in the decidua, including invasive cytotrophoblasts, macrophages, and endothelial, decidual, and dendritic cells. Cell-to-cell viral spread was revealed by focal extension of infected-cell clusters, inability to recover infectious extracellular virus, and high relative proportions (88 to 93%) of cell-associated viral DNA. Intriguingly, neutralizing HCMV hyperimmune globulins exhibited inhibitory activity against viral spread in the decidua even when added at 24 h postinfection—providing a mechanistic basis for their clinical use in prenatal prevention. The ex vivo-infected decidual cultures offer unique insight into patterns of viral tropism and spread, defining initial stages of congenital HCMV transmission, and can facilitate evaluation of the effects of new antiviral interventions within the maternal-fetal interface milieu.

The phenotypic spectrum of ARHGEF9 includes intellectual disability, focal epilepsy and febrile seizures

Mutations or structural genomic alterations of the X-chromosomal gene ARHGEF9 have been described in male and female patients with intellectual disability. Hyperekplexia and epilepsy were observed to a variable degree, but incompletely described. Here, we expand the phenotypic spectrum of ARHGEF9 by describing a large Ethiopian-Jewish family with epilepsy and intellectual disability. The four affected male siblings, their unaffected parents and two unaffected female siblings were recruited and phenotyped. Parametric linkage analysis was performed using SNP microarrays. Variants from exome sequencing in two affected individuals were confirmed by Sanger sequencing. All affected male siblings had febrile seizures from age 2–3xa0years and intellectual disability. Three developed afebrile seizures between age 7–17xa0years. Three showed focal seizure semiology. None had hyperekplexia. A novel ARHGEF9 variant (c.967G>A, p.G323R, NM_015185.2) was hemizygous in all affected male siblings and heterozygous in the mother. This family reveals that the phenotypic spectrum of ARHGEF9 is broader than commonly assumed and includes febrile seizures and focal epilepsy with intellectual disability in the absence of hyperekplexia or other clinically distinguishing features. Our findings suggest that pathogenic variants in ARHGEF9 may be more common than previously assumed in patients with intellectual disability and mild epilepsy.

Trained Memory of Human Uterine NK Cells Enhances Their Function in Subsequent Pregnancies

SUMMARY Natural killer cells (NKs) are abundant in the human decidua, regulating trophoblast invasion and angiogenesis. Several diseases of poor placental development are associated with first pregnancies, so we thus looked to characterize differences in decidual NKs (dNKs) in first versus repeated pregnancies. We discovered a population found in repeated pregnancies, which has a unique transcriptome and epigenetic signature, and is characterized by high expression of the receptors NKG2C and LILRB1. We named these cells Pregnancy Trained decidual NK cells (PTdNKs). PTdNKs have open chromatin around the enhancers of IFNG and VEGFA. Activation of PTdNKs led to increased production and secretion of IFN‐&ggr; and VEGF&agr;, with the latter supporting vascular sprouting and tumor growth. The precursors of PTdNKs seem to be found in the endometrium. Because repeated pregnancies are associated with improved placentation, we propose that PTdNKs, which are present primarily in repeated pregnancies, might be involved in proper placentation. Graphical Abstract Figure. No Caption available. HighlightsA unique subset of human natural killer cells exists in repeated pregnanciesThese NK cells, termed PTdNKs, express increased amounts of NKG2C and LILRB1PTdNKs secrete increased levels of IFN‐&ggr; and VEGF&agr;; the latter supports vascularization &NA; Natural killer cells are present in the human decidua, regulating trophoblast invasion and angiogenesis. Here, Gamliel et al. report on a special subset of human decidual natural killer cells, which “remember” pregnancy and better support subsequent pregnancies. This might explain why first pregnancies are at increased risk of developing diseases of poor placentation.

Lamotrigine as monotherapy in clinical practice: efficacy of various dosages in epilepsy

The study was designed to evaluate the optimal dosage of lamotrigine, as monotherapy, in the treatment of adults suffering from complex partial seizures with or without secondary generalization in everyday clinical practice.

Castor oil for induction of labor in post-date pregnancies: A randomized controlled trial

BACKGROUNDnCastor oil is a substance used for labor induction in an inpatient setting. However, its efficacy as an agent for the induction of labor, for post-date pregnancies in an outpatient setup is unknown.nnnOBJECTIVEnEfficacy of castor oil as an agent for the induction of labor, for post-date pregnancies in outpatient settings.nnnMETHODSnEighty-one women with a low-risk post-date singleton pregnancy with a Bishop score≤7, without effective uterine contractions were randomized to the intervention, 60ml of castor oil, or the control, 60ml of sun-flower oil. The primary outcome was proportion of women entering the active phase of labor 24, 36, 48h after ingestion. Secondary outcomes included meconium stained amniotic fluid, abnormal fetal heart rate tracing, cesarean section rate, instrumental deliveries, birth weight, 5min Apgar score, chorioamnionitis, hypertensive complications, retained placenta, and post-partum hemorrhage.nnnFINDINGSnIntervention and control groups included 38 and 43 women, respectively. No differences in baseline characteristics, except for age were noted. The observed interaction between castor oil and parity was significant (pinteraction=0.02). Multiparous women in the intervention group exhibited a significant beneficial effect on entering active labor within 24, 36 and 48h after castor oil consumption compared with the placebo (Hazard Ratio=2.93, p=0.048; Hazard Ratio=3.29, p=0.026; Hazard Ratio=2.78, p=0.042 respectively). This effect was not noted among primiparous women. No differences in rate of obstetric complications or adverse neonatal outcomes were noted.nnnCONCLUSIONnCastor oil is effective for labor induction, in post-date multiparous women in outpatient settings.

Estimation of seizures prevalence in ischemic strokes after thrombolytic therapy

PURPOSEnPost stroke seizures are a complication that occur in 5-20% of acute ischemic stroke (AIS) patients, cause a reduction in quality of life and a greater burden on the health system. There is not enough data regarding an association between todays standard of care treatment in AIS: recombinant tissue plasminogen activator (r-tPA) and the risk for post stroke seizures. Our aim in this work is to reveal such a connection.nnnMETHODnA non-randomized retrospective cohort-controlled study of 234 patients, who were hospitalized with acute ischemic stroke at Kaplan Medical Center in the years 2009-2015 and were divided into two different treatment groups: r-tPA and antiaggregant therapy(nu2009=u2009141) and antiaggregant therapy only (nu2009=u200995) was conducted by us. Information regarding demographics, medical history, nature of the event, including NIHSS values on admission, discharge, and post stroke seizures, were obtained for each group. Follow-up was done for one year.nnnRESULTSnDuring the year of follow-up, 19 patients (8.1%) of the overall cohort, developed seizures: 12 of them (12.6%) belonged to the control group and 7 (5%) to the study group pu2009<u20090.05). Results showed a decrease in the risk for developing seizure when treated with r-tpA, comparing to antiaggregants (odds ratiou2009=u20090.64).nnnCONCLUSIONnThis study suggests there is an association between r-tPA treatment and reduction of the risk for post stroke seizures.

Occurrence of overt seizures in comatose survivor patients treated with targeted temperature

Unconscious patients after out‐of‐hospital cardiac arrest have a high risk of death. Therapeutic hypothermia is recommended by international resuscitation guidelines in order to attenuate secondary destructive physiological processes such as reperfusion injury, apoptosis, and cerebral edema. The target temperature to reach ranges between 32 and 34°C for at least 24 hr. Hypothermia can induce metabolic disturbances. There are some reports in the literature indicating the presence of seizures during targeted temperature management. On the other hand, postanoxic seizures are a sign of unfavorable neurological outcome. The purpose of this study was to evaluate the occurrence of overt seizures in comatose survivor patients treated with targeted temperature in respect to overt seizures in a normal temperature group of comatose patients.