Muscular phenotype description of abnormal THOC2 splicing

Until recently, the disease known to be associated with THOC2 mutations was Intellectual developmental disorder, X-linked 12 (MIM300957). However, recently, fetal arthrogryposis multiplex congenita has been associated with a specific splice site mutation in the THOC2 gene. We report a family with the same splice site mutation in the THOC2 gene involved in fetal arthrogryposis as well. We provide the first description of the muscular phenotype of this disease which reveals the presence of cytoplasmic bodies. Our findings expand the clinical phenotype of THOC2 gene related defects.

Androgenetic/biparental mosaicism in a diploid mole-like conceptus: report of a case with triple paternal contribution

Hydatidiform moles (HMs) are divided into two types: partial hydatidiform mole (PHM) which is most often diandric monogynic triploid and complete hydatidiform mole (CHM) which is most often diploid androgenetic. Morphological features and p57 immunostaining are routinely used to distinguish both entities. Genetic analyses are required in challenging cases to determine the parental origin of the genome and ploidy. Some gestations cannot be accurately classified however. We report a case with atypical pathologic and genetic findings that correspond neither to CHM nor to PHM. Two populations of villi with divergent and discordant p57 expression were observed: morphologically normal p57 + villi and molar-like p57 discordant villi with p57 + stromal cells and p57 - cytotrophoblasts. Genotyping of DNA extracted from microdissected villi demonstrated that the conceptus was an androgenetic/biparental mosaic, originating from a zygote with triple paternal contribution, and that only the p57 - cytotrophoblasts were purely androgenetic, increasing the risk of neoplastic transformation.

Artifacts and main lesions in fetal ocular histology

Histological artifacts in fetal eyes can involve different tissues and can be related to mechanical or autolytic lesions, fixation, the cause of death or the cutting technique. Knowing the causes, effects and appearance of artifacts allow the minimization of the risk of avoidable artifacts and help distinguish them from "true" pathological lesions. We describe these different types of artifacts and specifically analyze their involvement in different tissue structures of the eye. We compare them with primary fetal ocular lesions. Given the wide variety of artifacts, the identification of lesions in fetal eyes must be done with caution, since differentiating true lesions from artifacts requires some experience and relies on both macroscopic examination and microscopic analyses, with ideally comparisons with references' images of normal tissues of the same gestational age.

Severe Antenatal Hypertrophic Cardiomyopathy Secondary to ACAD9-Related Mitochondrial Complex I Deficiency

Introduction

Antenatal presentation of hypertrophic cardiomyopathy (HCM) is rare. We describe familial recurrence of antenatal HCM associated with intrauterine growth restriction and the diagnostic process undertaken.

Methods

Two pregnancies with antenatal HCM were followed up. Biological assessment including metabolic analyses, genetic analyses, and respiratory chain study was performed. We describe the clinical course of these two pregnancies, antenatal manifestations as well as specific histopathological findings, and review the literature.

Results

The assessment revealed a deficiency in complex I of the respiratory chain and two likely pathogenic variations in the ACAD9 gene.

Discussion and Conclusion

Antenatal HCM is rare and a diagnosis is not always made. In pregnancies presenting with cardiomyopathy and intrauterine growth restriction, ACAD9 deficiency should be considered as one of the potential underlying diagnoses, and ACAD9 molecular testing should be included among other prenatal investigations.

Estrogen Actions in Placental Vascular Morphogenesis and Spiral Artery Remodeling: A Comparative View between Humans and Mice

Estrogens, mainly 17β-estradiol (E2), play a critical role in reproductive organogenesis, ovulation, and fertility via estrogen receptors. E2 is also a well-known regulator of utero-placental vascular development and blood-flow dynamics throughout gestation. Mouse and human placentas possess strikingly different morphological configurations that confer important reproductive advantages. However, the functional interplay between fetal and maternal vasculature remains similar in both species. In this review, we briefly describe the structural and functional characteristics, as well as the development, of mouse and human placentas. In addition, we summarize the current knowledge regarding estrogen actions during utero-placental vascular morphogenesis, which includes uterine angiogenesis, the control of trophoblast behavior, spiral artery remodeling, and hemodynamic adaptation throughout pregnancy, in both mice and humans. Finally, the estrogens that are present in abnormal placentation are also mentioned. Overall, this review highlights the importance of the actions of estrogens in the physiology and pathophysiology of placental vascular development.

Overlapping cortical malformations in patients with pathogenic variants in GRIN1 and GRIN2B

BACKGROUND

Malformations of cortical development (MCDs) have been reported in a subset of patients with pathogenic heterozygous variants in GRIN1 or GRIN2B, genes which encode for subunits of the N-methyl-D-aspartate receptor (NMDAR). The aim of this study was to further define the phenotypic spectrum of NMDAR-related MCDs.

METHODS

We report the clinical, radiological and molecular features of 7 new patients and review data on 18 previously reported individuals with NMDAR-related MCDs. Neuropathological findings for two individuals with heterozygous variants in GRIN1 are presented. We report the clinical and neuropathological features of one additional individual with homozygous pathogenic variants in GRIN1.

RESULTS

Heterozygous variants in GRIN1 and GRIN2B were associated with overlapping severe clinical and imaging features, including global developmental delay, epilepsy, diffuse dysgyria, dysmorphic basal ganglia and hippocampi. Neuropathological examination in two fetuses with heterozygous GRIN1 variants suggests that proliferation as well as radial and tangential neuronal migration are impaired. In addition, we show that neuronal migration is also impaired by homozygous GRIN1 variants in an individual with microcephaly with simplified gyral pattern.

CONCLUSION

These findings expand our understanding of the clinical and imaging features of the 'NMDARopathy' spectrum and contribute to our understanding of the likely underlying pathogenic mechanisms leading to MCD in these patients.

Lésions placentaires graves dues à une infection maternelle par le SARS-CoV-2 associées à une mort fœtale intra-utérine

L’infection par le SRAS-CoV-2 peut provoquer des lésions placentaires sévères conduisant rapidement à une mort fœtale intra-utérine (MFIU). Entre août 2020 et septembre 2021, nous avons reçu et analysé 50 placentas de mères non vaccinées positives au COVID-19, dans le service de pathologie de Toulouse.

Le but de notre étude est de décrire les caractéristiques clinicopathologiques de ces atteintes placentaires et d’en comprendre la physiopathologie.

Dix d’entre eux (20 %) présentaient des lésions placentaires avec une immunohistochimie positive au SARS-CoV-2 au niveau du trophoblaste villositaire. Dans cinq cas (10 %), nous avons observé des lésions placentaires massives associant nécrose trophoblastique, dépôts fibrinoides, intervillite ainsi que des modifications hémorragiques étendues dues à l’infection par le SARS-CoV-2 probablement responsable de la MFIU par insuffisance placentaire fonctionnelle. Dans cinq autres cas, nous avons trouvé des lésions placentaires similaires mais avec une distribution focale ayant conduit à une naissance vivante.

Ces lésions sont indépendantes de la sévérité clinique maternelle de l’infection à COVID-19 car elles surviennent malgré des symptômes maternels bénins les rendant difficiles à prévoir. Dans nos cas, elles sont apparues 1 à 3 semaines après un test RT-PCR maternel positif au SRAS-CoV-2 et ont été observées au cours des 2^e et 3^e trimestres de la grossesse. Lorsque ces lésions sont focales, elles n’entraînent pas de MFIU mais peuvent être associées à un retard de croissance intra-utérin.

Severe placental lesions due to maternal SARS-CoV-2 infection associated to intrauterine fetal death

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection can cause severe placental lesions leading rapidly to intrauterine fetal death (IUFD). From August 2020 to September 2021, in the pathology department of Toulouse Oncopole, we analyzed 50 placentas from COVID-19–positive unvaccinated mothers.

The purpose of our study is to describe the clinicopathological characteristics of these placental damages and to understand the pathophysiology.

Ten of them (20%) showed placental lesions with positive immunohistochemistry for SARS-CoV-2 in villous trophoblasts. In five cases (10%), we observed massive placental damage associating trophoblastic necrosis, fibrinous deposits, intervillositis, as well as extensive hemorrhagic changes due to SARS-CoV-2 infection probably responsible of IUFD by functional placental insufficiency. In five other cases, we found similar placental lesions but with a focal distribution that did not lead to IUFD but live birth.

These lesions are independent of maternal clinical severity of COVID-19 infection because they occur despite mild maternal symptoms and are therefore difficult to predict. In our cases, they occurred 1–3 weeks after positive SARS-CoV-2 maternal real-time polymerase chain reaction testing and were observed in the 2nd and 3rd trimesters of pregnancies. When these lesions are focal, they do not lead to IUFD and can be involved in intrauterine growth restriction.

Our findings, together with recent observations, suggest that future pregnancy guidance should include stricter pandemic precautions such as screening for a wider array of COVID-19 symptoms, enhanced ultrasound monitoring, as well as newborn medical surveillance.

Human cytomegalovirus infection is associated with increased expression of the lissencephaly gene PAFAH1B1 encoding LIS1 in neural stem cells and congenitally infected brains

Congenital infection of the central nervous system by human cytomegalovirus (HCMV) is a leading cause of permanent sequelae, including mental retardation or neurodevelopmental abnormalities. The most severe complications include smooth brain or polymicrogyria, which are both indicative of abnormal migration of neural cells, although the underlying mechanisms remain to be determined. To gain better insight on the pathogenesis of such sequelae, we assessed the expression levels of a set of neurogenesis-related genes, using HCMV-infected human neural stem cells derived from embryonic stem cells (NSCs). Among the 84 genes tested, we found dramatically increased expression of the gene PAFAH1B1, encoding LIS1 (lissencephaly-1), in HCMV-infected versus uninfected NSCs. Consistent with these findings, western blotting and immunofluorescence analyses confirmed the increased levels of LIS1 in HCMV-infected NSCs at the protein level. We next assessed the migratory abilities of HCMV-infected NSCs and observed that infection strongly impaired the migration of NSCs, without detectable effect on their proliferation. Moreover, we observed increased immunostaining for LIS1 in brains of congenitally infected fetuses, but not in control samples, highlighting the clinical relevance of our findings. Of note, PAFAH1B1 mutations (resulting in either haploinsufficiency or gain of function) are primary causes of hereditary neurodevelopmental diseases. Notably, mutations resulting in PAFAH1B1 haploinsufficiency cause classic lissencephaly. Taken together, our findings suggest that PAFAH1B1 is a critical target of HCMV infection. They also shine a new light on the pathophysiological basis of the neurological outcomes of congenital HCMV infection, by suggesting that defective neural cell migration might contribute to the pathogenesis of the neurodevelopmental sequelae of infection. © 2021 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Re-focusing on Agnathia-Otocephaly complex

OBJECTIVES

Agnathia-otocephaly complex is a rare condition characterized by mandibular hypoplasia or agnathia, ear anomalies (melotia/synotia) and microstomia with aglossia. This severe anomaly of the first branchial arch is most often lethal. The estimated incidence is less than 1 in 70.000 births, with etiologies linked to both genetic and teratogenic factors. Most of the cases are sporadic. To date, two genes have been described in humans to be involved in this condition: OTX2 and PRRX1. Nevertheless, the overall proportion of mutated cases is unknown and a significant number of patients remain without molecular diagnosis. Thus, the involvement of other genes than OTX2 and PRRX1 in the agnathia-otocephaly complex is not unlikely. Heterozygous mutations in Cnbp in mice are responsible for mandibular and eye defects mimicking the agnathia-otocephaly complex in humans and appear as a good candidate. Therefore, in this study, we aimed (i) to collect patients presenting with agnathia-otocephaly complex for screening CNBP, in parallel with OTX2 and PRRX1, to check its possible implication in the human phenotype and (ii) to compare our results with the literature data to estimate the proportion of mutated cases after genetic testing.

MATERIALS AND METHODS

In this work, we describe 10 patients suffering from the agnathia-otocephaly complex. All of them benefited from array-CGH and Sanger sequencing of OTX2, PRRX1 and CNBP. A complete review of the literature was made using the Pubmed database to collect all the patients described with a phenotype of agnathia-otocephaly complex during the 20 last years (1998-2019) in order (i) to study etiology (genetic causes, iatrogenic causes…) and (ii), when genetic testing was performed, to study which genes were tested and by which type of technologies.

RESULTS

In our 10 patients' cohort, no point mutation in the three tested genes was detected by Sanger sequencing, while array-CGH has allowed identifying a 107-kb deletion encompassing OTX2 responsible for the agnathia-otocephaly complex phenotype in 1 of them. In 4 of the 70 cases described in the literature, a toxic cause was identified and 22 out the 66 remaining cases benefited from genetic testing. Among those 22 patients, 6 were carrying mutation or deletion in the OTX2 gene and 4 in the PRRX1 gene. Thus, when compiling results from our cohort and the literature, a total of 32 patients benefited from genetic testing, with only 34% (11/32) of patients having a mutation in one of the two known genes, OTX2 or PRRX1.

CONCLUSIONS

From our work and the literature review, only mutations in OTX2 and PRRX1 have been found to date in patients, explaining around one third of the etiologies after genetic testing. Thus, agnathia-otocephaly complex remains unexplained in the majority of the patients, which indicates that other factors might be involved. Although involved in first branchial arch defects, no mutation in the CNBP gene was found in this study. This suggests that mutations in CNBP might not be involved in such phenotype in humans or that, unlike in mice, a compensatory effect might exist in humans. Nevertheless, given that agnathia-otocephaly complex is a rare phenotype, more patients have to be screened for CNBP mutations before we definitively conclude about its potential implication. Therefore, this work presents the current state of knowledge on agnathia-otocephaly complex and underlines the need to expand further the understanding of the genetic bases of this disorder, which remains largely unknown.

CLINICAL RELEVANCE

We made here an update and focus on the clinical and genetic aspects of agnathia-otocephaly complex as well as a more general review of craniofacial development.

Regulation of human cerebral cortical development by EXOC7 and EXOC8, components of the exocyst complex, and roles in neural progenitor cell proliferation and survival

PURPOSE

The exocyst complex is a conserved protein complex that mediates fusion of intracellular vesicles to the plasma membrane and is implicated in processes including cell polarity, cell migration, ciliogenesis, cytokinesis, autophagy, and fusion of secretory vesicles. The essential role of these genes in human genetic disorders, however, is unknown.

METHODS

We performed homozygosity mapping and exome sequencing of consanguineous families with recessively inherited brain development disorders. We modeled an EXOC7 splice variant in vitro and examined EXOC7 messenger RNA (mRNA) expression in developing mouse and human cortex. We modeled exoc7 loss-of-function in a zebrafish knockout.

RESULTS

We report variants in exocyst complex members, EXOC7 and EXOC8, in a novel disorder of cerebral cortex development. In EXOC7, we identified four independent partial loss-of-function (LOF) variants in a recessively inherited disorder characterized by brain atrophy, seizures, and developmental delay, and in severe cases, microcephaly and infantile death. In EXOC8, we found a homozygous truncating variant in a family with a similar clinical disorder. We modeled exoc7 deficiency in zebrafish and found the absence of exoc7 causes microcephaly.

CONCLUSION

Our results highlight the essential role of the exocyst pathway in normal cortical development and how its perturbation causes complex brain disorders.

Further delineation of the clinical spectrum of KAT6B disorders and allelic series of pathogenic variants

PURPOSE

Genitopatellar syndrome and Say-Barber-Biesecker-Young-Simpson syndrome are caused by variants in the KAT6B gene and are part of a broad clinical spectrum called KAT6B disorders, whose variable expressivity is increasingly being recognized.

METHODS

We herein present the phenotypes of 32 previously unreported individuals with a molecularly confirmed diagnosis of a KAT6B disorder, report 24 new pathogenic KAT6B variants, and review phenotypic information available on all published individuals with this condition. We also suggest a classification of clinical subtypes within the KAT6B disorder spectrum.

RESULTS

We demonstrate that cerebral anomalies, optic nerve hypoplasia, neurobehavioral difficulties, and distal limb anomalies other than long thumbs and great toes, such as polydactyly, are more frequently observed than initially reported. Intestinal malrotation and its serious consequences can be present in affected individuals. Additionally, we identified four children with Pierre Robin sequence, four individuals who had increased nuchal translucency/cystic hygroma prenatally, and two fetuses with severe renal anomalies leading to renal failure. We also report an individual in which a pathogenic variant was inherited from a mildly affected parent.

CONCLUSION

Our work provides a comprehensive review and expansion of the genotypic and phenotypic spectrum of KAT6B disorders that will assist clinicians in the assessment, counseling, and management of affected individuals.

p57-discordant villi in hydropic products of conception: a clinicopathological study of 70 cases

p57 immunostaining is performed on hydropic products of conception to diagnose hydatidiform moles (HMs), which can progress to gestational trophoblastic neoplasia. Partial hydatidiform mole (PHM) and hydropic abortion (HA) display positive staining in stromal and cytotrophoblastic cells, whereas complete hydatidiform mole (CHM) is characterized by loss of p57 expression in both cell types. In some cases, an aberrant pattern is observed, called discordant p57 expression, with positive cytotrophoblast staining and negative stromal staining, or vice versa. The aim of this study was to describe the clinical, biological, and pathological characteristics of p57-discordant villi (p57DV) and other associated populations in cases of divergent p57 expression and to compare the evolutions of p57DV-associated and classic CHMs. Seventy cases of p57DV diagnosed by referent pathologists were divided into two groups, G1: p57DV ± non-CHM component (n = 22) and G2: p57DV + CHM component (n = 48). p57DV morphology was similar in the two groups. Observation of more than two populations and hybrid villi on p57 immunostaining were significantly more frequent in G2. The clinical, ultrasound, and biological presentations of p57DV-associated and classic CHMs were similar. The initial pathological diagnosis was more frequently incorrect, missing the CHM component, for the p57DV-associated CHMs. Molecular genotyping was informative in seven cases and identified as androgenetic/biparental mosaicism in four cases. These results show that p57DV are a diagnostic challenge for pathologists and that most are associated with a CHM component. However, the clinical management of p57DV-associated CHMs should be the same as that of classic CHMs.

Mutations in GREB1L Cause Bilateral Kidney Agenesis in Humans and Mice

Congenital anomalies of the kidney and urinary tract (CAKUT) constitute a major cause of chronic kidney disease in children and 20% of prenatally detected anomalies. CAKUT encompass a spectrum of developmental kidney defects, including renal agenesis, hypoplasia, and cystic and non-cystic dysplasia. More than 50 genes have been reported as mutated in CAKUT-affected case subjects. However, the pathophysiological mechanisms leading to bilateral kidney agenesis (BKA) remain largely elusive. Whole-exome or targeted exome sequencing of 183 unrelated familial and/or severe CAKUT-affected case subjects, including 54 fetuses with BKA, led to the identification of 16 heterozygous variants in GREB1L (growth regulation by estrogen in breast cancer 1-like), a gene reported as a target of retinoic acid signaling. Four loss-of-function and 12 damaging missense variants, 14 being absent from GnomAD, were identified. Twelve of them were present in familial or simplex BKA-affected case subjects. Female BKA-affected fetuses also displayed uterus agenesis. We demonstrated a significant association between GREB1L variants and BKA. By in situ hybridization, we showed expression of Greb1l in the nephrogenic zone in developing mouse kidney. We generated a Greb1l knock-out mouse model by CRISPR-Cas9. Analysis at E13.5 revealed lack of kidneys and genital tract anomalies in male and female Greb1l^-/- embryos and a slight decrease in ureteric bud branching in Greb1l^+/- embryos. We showed that Greb1l invalidation in mIMCD3 cells affected tubulomorphogenesis in 3D-collagen culture, a phenotype rescued by expression of the wild-type human protein. This demonstrates that GREB1L plays a major role in early metanephros and genital development in mice and humans.

PPARγ Is Activated during Congenital Cytomegalovirus Infection and Inhibits Neuronogenesis from Human Neural Stem Cells

Congenital infection by human cytomegalovirus (HCMV) is a leading cause of permanent sequelae of the central nervous system, including sensorineural deafness, cerebral palsies or devastating neurodevelopmental abnormalities (0.1% of all births). To gain insight on the impact of HCMV on neuronal development, we used both neural stem cells from human embryonic stem cells (NSC) and brain sections from infected fetuses and investigated the outcomes of infection on Peroxisome Proliferator-Activated Receptor gamma (PPARγ), a transcription factor critical in the developing brain. We observed that HCMV infection dramatically impaired the rate of neuronogenesis and strongly increased PPARγ levels and activity. Consistent with these findings, levels of 9-hydroxyoctadecadienoic acid (9-HODE), a known PPARγ agonist, were significantly increased in infected NSCs. Likewise, exposure of uninfected NSCs to 9-HODE recapitulated the effect of infection on PPARγ activity. It also increased the rate of cells expressing the IE antigen in HCMV-infected NSCs. Further, we demonstrated that (1) pharmacological activation of ectopically expressed PPARγ was sufficient to induce impaired neuronogenesis of uninfected NSCs, (2) treatment of uninfected NSCs with 9-HODE impaired NSC differentiation and (3) treatment of HCMV-infected NSCs with the PPARγ inhibitor T0070907 restored a normal rate of differentiation. The role of PPARγ in the disease phenotype was strongly supported by the immunodetection of nuclear PPARγ in brain germinative zones of congenitally infected fetuses (N = 20), but not in control samples. Altogether, our findings reveal a key role for PPARγ in neurogenesis and in the pathophysiology of HCMV congenital infection. They also pave the way to the identification of PPARγ gene targets in the infected brain.

Congenital infection by human cytomegalovirus (HCMV) might result in permanent neurological sequelae, including sensorineural deafness, cerebral palsies or devastating neurodevelopmental abnormalities. Infants with such sequelae represent about 0.1% of all live births (>5500 per year in the USA). Given the considerable health and societal burden, a better insight on disease pathogenesis is urgently needed to design new therapeutic or prognostic tools. Here, we studied the impact of HCMV on neuronal development, using human neural progenitors (NSC) as a disease model. In particular, we investigated the outcome of infection on Peroxisome Proliferator-Activated Receptor gamma (PPARγ, a key protein in the regulation of metabolism, inflammation and cell differentiation. We disclosed that HCMV infection strongly increases levels and activity of PPARγ in NSCs. In vitro experiments showed that PPARγ activity inhibits the differentiation of NSCs into neurons. We also found increased PPARγ expression in brains of in utero infected fetuses, but not in controls, suggesting that PPARγ is a key effector of HCMV infection also in vivo. Our study provides new insights on the pathogenesis of HCMV infection and paves the way to the discovery of PPARγ-related molecules secreted in the infected brain.

Immunocytochemical staining for p53 and Ki-67 helps to characterise urothelial cells in urine cytology

OBJECTIVE

The presence of atypical cells in urine cytology is unsatisfactory for both cytologists and clinicians. The objective of this study was to test whether p53 and Ki-67 immunostaining could improve urothelial carcinoma (UC) detection on urinary cytology.

METHODS

A total of 196 urine samples were analysed, 142 from the bladder, 41 from the upper tract and 13 from ileal bladder replacement. Cytology results were expressed as normal (N) (n = 81), atypia cannot exclude low-grade UC (ALG) (n = 25), suspicious for high-grade UC (SHG) (n = 39) and high-grade UC (HG) (n = 51). Actual diagnoses were confirmed by histopathological analysis, cystoscopic examination or follow-up for at least 1 year. Immunocytochemistry performed on CytoSpin^™ slides allowed the determination of the percentage of positive cells with p53 and Ki-67.

RESULTS

The median percentage values [first to third quartile] of p53 and Ki-67 were 0 [0-5] and 0 [0-1] for N cytology, 5 [0-40] and 2 [1-10] for ALG, 10 [0-30] and 6 [3-25] for SHG, and 30 [10-80] and 20 [10-30] for HG, respectively. Statistically higher values were observed for both tests (P < 0.001) in positive cytologies (ALG, SHG and HG). The optimal cut-offs were 5% for p53 and 3% for Ki-67. The sensitivity and specificity for the detection of all UC were 86.4% and 76.7% for cytology alone, 81.3% and 93.2% for cytology and p53, 75.7% and 88% for cytology and Ki-67, and 68.9% and 97.5% for cytology, p53 and Ki-67, respectively.

CONCLUSION

Using p53 and/or Ki-67 in addition to cytology increases the specificity without penalising the sensitivity.

Improving the cytological diagnosis of intraocular lymphoma from vitreous fluid

AIMS

To improve the cytological diagnosis of retinal lymphoma on vitreous fluid using improved cell collection and systematic analyses.

METHODS AND RESULTS

Since October 2010, we have developed and optimized in our department a method with which to perform the diagnosis of retinal lymphoma. The vitreous sample was collected in a tube containing RPMI-1640 medium, decomplemented fetal bovine serum, and gentamicin. The transport and technical steps were performed at 4°C. Systematically, cytological examination with May-Grünwald-Giemsa staining and immunocytochemistry (mainly anti-CD3, anti-CD20 and anti-CD68 antibodies) were performed on cytospins. Whenever possible, determination of B-cell clonality, flow cytometry and determination of the interleukin (IL)-10/IL-6 ratio were performed. From October 2010 to June 2013, with this optimized protocol, 38 vitreous cytological samples from 32 patients were analysed, and a final diagnosis was possible, avoiding a biopsy, in all cases except one.

CONCLUSION

The preservation of vitreous fluid cells on culture medium led to the diagnosis of retinal lymphoma in 10 of 12 cases, and exclusion of this diagnosis in 26 cases. This protocol may be applied even when the delay in shipping from the surgery to the pathology departments exceeds 1 h.

Specific infiltration pattern of FOXP3+ regulatory T cells in chronic histiocytic intervillositis of unknown etiology

INTRODUCTION

Chronic histiocytic intervillositis of unknown etiology (CIUE) is a rare placental lesion characterized by an intervillous mononuclear inflammatory infiltrate of maternal origin. Although the mechanism and origin of these lesions are currently not understood, they appear to be related to an immune conflict between mother and fetus cells.

AIM

To clarify the inflammatory cell profile and evaluate the T regulatory lymphocyte (Treg) status in CIUE.

MATERIALS AND METHODS

All cases of CIUE that occurred over an 8-year period were analyzed using immunohistochemistry.

RESULTS

The inflammatory profile of CIUE was characterized by a clearly predominant component of histiocytic cells (80% ± 6.9) associated with some T cells (24% ± 5.7). The ratio of CD4+ versus CD8+ T cells was close to 1. This profile differs from infectious disease and chronic histiocytic villitis, the main differential diagnoses of CIUE. As for normal pregnancies most regulatory T cells were localized in the decidua basalis. Nevertheless, their appearance was also noted in the intervillous space. In both the intervillous space and the deciduas the number of Tregs gradually increased from grade 1 to 3.

CONCLUSION

We found that CIUE is associated with an increase in Treg lymphocytes in the decidua basalis and the intervillous space. Contrary to previously published data on human miscarriage, this result appears to be specific to CIUE and would support the hypothesis of an immunopathological disorder for CIUE.

Identification of mutations in TMEM5 and ISPD as a cause of severe cobblestone lissencephaly

Cobblestone lissencephaly is a peculiar brain malformation with characteristic radiological anomalies. It is defined as cortical dysplasia that results when neuroglial overmigration into the arachnoid space forms an extracortical layer that produces agyria and/or a "cobblestone" brain surface and ventricular enlargement. Cobblestone lissencephaly is pathognomonic of a continuum of autosomal-recessive diseases characterized by cerebral, ocular, and muscular deficits. These include Walker-Warburg syndrome, muscle-eye-brain disease, and Fukuyama muscular dystrophy. Mutations in POMT1, POMT2, POMGNT1, LARGE, FKTN, and FKRP identified these diseases as alpha-dystroglycanopathies. Our exhaustive screening of these six genes, in a cohort of 90 fetal cases, led to the identification of a mutation in only 53% of the families, suggesting that other genes might also be involved. We therefore decided to perform a genome-wide study in two multiplex families. This allowed us to identify two additional genes: TMEM5 and ISPD. Because TMEM has a glycosyltransferase domain and ISPD has an isoprenoid synthase domain characteristic of nucleotide diP-sugar transferases, these two proteins are thought to be involved in the glycosylation of dystroglycan. Further screening of 40 families with cobblestone lissencephaly identified nonsense and frameshift mutations in another four unrelated cases for each gene, increasing the mutational rate to 64% in our cohort. All these cases displayed a severe phenotype of cobblestone lissencephaly A. TMEM5 mutations were frequently associated with gonadal dysgenesis and neural tube defects, and ISPD mutations were frequently associated with brain vascular anomalies.

NEK1 and DYNC2H1 are both involved in short rib polydactyly Majewski type but not in Beemer Langer cases

BACKGROUND

The lethal short rib polydactyly syndromes (SRP type I-IV) are characterised by notably short ribs, short limbs, polydactyly, multiple anomalies of major organs, and autosomal recessive mode of inheritance. Among them, SRP type II (Majewski; MIM 263520) is characterised by short ovoid tibiae or tibial agenesis and is radiographically closely related to SRP type IV (Beemer-Langer; MIM 269860) which is distinguished by bowed radii and ulnae and relatively well tubulated tibiae. NEK1 mutations have been recently identified in SRP type II. Double heterozygosity for mutations in both NEK1 and DYNC2H1 in one SRP type II case supported possible digenic diallelic inheritance.

METHODS

The aim of this study was to screen DYNC2H1 and NEK1 in 13 SRP type II cases and seven SRP type IV cases. It was not possible to screen DYNC2H1 in two patients due to insufficient amount of DNA.

RESULTS

The study identified homozygous NEK1 mutations in 5/13 SRP type II and compound heterozygous DYNC2H1 mutations in 4/12 cases. Finally, NEK1 and DYNC2H1 were excluded in 3/12 SRP type II and in all SRP type IV cases. The main difference between the mutation positive SRP type II group and the mutation negative SRP type II group was the presence of holoprosencephaly and polymycrogyria in the mutation negative group.

CONCLUSION

This study confirms that NEK1 is one gene causing SRP type II but also reports mutations in DYNC2H1, expanding the phenotypic spectrum of DYNC2H1 mutations. The exclusion of NEK1 and DYNC2H1 in 3/12 SRP type II and in all SRP type IV cases further support genetic heterogeneity.

Investigation of the significance of Oil Red O-positive macrophage excess in bronchoalveolar lavage fluid during HIV infection

OBJECTIVE

To assess the significance of increased levels of Oil Red O-positive macrophages (ORO-PM) in bronchoalveolar lavage fluids (BALFs) from HIV-positive patients.

METHODS

Cytological data for seventy BALF samples from 66 consecutive HIV-infected patients were analysed according to antiretroviral therapy regimen, presence of Pneumocystis jiroveci infection, blood CD4(+) T cell count, HIV-1 viral load and plasma lipid levels. Non-parametric tests were used to compare the values between groups.

RESULTS

The percentages of ORO-PM were high in this group: 40% [6-80] (median [interquartile range]). They were positively correlated with the BALF total cell count, 21% [5-48.5] for <300 cells/mm(3) and 60% [26.5-80] for >300 cells/mm(3) (P<0.01) but inversely correlated with the percentage of BALF lymphocytes, 50% [20-80] for <15% lymphocytes and 11.5% [2-47] for ≥15% lymphocytes (P<0.01). Antiretroviral therapy with or without protease inhibitors, plasma lipid levels, HIV-1 viral load, blood CD4(+) T cell count or presence of a Pneumocystis jiroveci infection were not correlated with the ORO-PM status.

CONCLUSION

Significantly increased numbers of ORO-PM were correlated with high total cell counts and low lymphocyte counts in BALF, irrespective of disease activity or treatment. Extended work on a larger series of patients needs to be conducted.

Cerebrospinal fluid cytologic findings of a pleomorphic xanthoastrocytoma: a case report

BACKGROUND

Pleomorphic xanthoastrocytoma (PXA) is a rare astrocytic neoplasm with a relatively favorable prognosis. Characteristic histologic features include pleomorphic tumor cells and lipidized cells expressing glial fibrillary acidic protein (GFAP), corresponding to a World Health Organization grade 2 tumor. Cytologic features of PXA have been rarely described, only in squash specimens, but only 2 cases are reported in cerebrospinal fluid (CSF).

CASE

A 45-year-old woman complained of severe headaches and diplopia. Computed tomography of the central nervous system revealed a supracallous periventricular tumor mass suggestive of either a lymphoma or a metastatic carcinoma. CSF revealed 18 cells/mm3 and contained numerous tumor cells highly pleomorphic in size and shape. Some atypical cells of moderate size were closely packed with well-defined cytoplasmic limits and a vacuolated appearance, suggesting an epithelial proliferation. On immunocytochemistry atypical cells were positive for GFAP, S100 protein and synaptophysin but were negative for pancytokeratins and epithelial membrane antigen. A primitive glial proliferation was found, and paraffin-embedded tumor tissue obtained by biopsy confirmed the diagnosis of anaplastic PXA.

CONCLUSION

Observation of PXA in CSF might cause some differential diagnosis problems, especially with a metastatic epithelial malignancy. We present a case of anaplastic PXA with an unusual periventricular location and its cytologic features in CSF.

Chronic intervillositis of unknown etiology (CIUE): relation between placental lesions and perinatal outcome

OBJECTIVES

To evaluate perinatal outcome of pregnancies complicated by chronic intervillositis of unknown etiology (CIUE) and to study the relation between extent of such placental histological lesions and clinical expression.

STUDY DESIGN

Descriptive and retrospective study including all cases of CIUE diagnosed between 2000 and 2006 in the university hospital of Toulouse (France). Perinatal outcome was evaluated according to the extent of placental lesions assessed by semi-quantitative graduation.

RESULTS

Twenty pregnancies complicated by CIUE were included (14 patients). Three pregnancies were prematurely interrupted spontaneously during the first trimester. Perinatal outcome of the remaining 17 pregnancies beyond 22 WG was: 4 intrauterine fetal deaths, 3 terminations of pregnancy for early and severe intrauterine growth restriction (IUGR), and 10 live births (58.8%). All fetal deaths, 82.3% of pregnancies beyond 22 WG and 70% of live births were growth restricted. Severe intervillositis with massive fibrinoid deposition was associated with a severe perinatal prognosis whereas focal forms had a best evolution. The rate of recurrence was 100% in the reported cases.

CONCLUSION

CIUE have a poor perinatal outcome and a high rate of recurrence. There is a relation between clinical expression and histological lesions.

Human fetal chromaffin cells: A potential tool for cell pain therapy

Transplantation of adrenal medulla cells has been proposed in the treatment of various conditions. Indeed, these cells possess a bipotentiality: neural and neuroendocrine, which could be exploited for brain repair or pain therapy. In a previous study, we characterized these human cells in vitro over 7-10 gestational weeks (GW) [Zhou, H., Aziza, J., Sol, J.C., Courtade-Saidi, M., Chatelin, S., Evra, C., Parant, O., Lazorthes, Y., and Jozan, S., 2006. Cell therapy of pain: Characterization of human fetal chromaffin cells at early adrenal medulla development. Exp. Neurol. 198, 370-381]. We report here our results on the extension to 23 GW. This developmental period can be split into three stages. During the first stage (7-10 GW), we observed in situ that extra-adrenal surrounding cells display the same morphology and phenotype as the intra-adrenal chromaffin cells. We also found that the intra-adrenal chromaffin cells could be committed in vitro towards an adrenergic phenotype using differentiating agents. During the second stage (11 to 15-16 GW), two types of cells (Type 1 and Type 2 cells) were identified morphologically both inside and outside the gland. Interestingly, we noted that the Type 2 cells stem from the Type 1 cells. However, during this developmental period only the intra-adrenal Type 2 cells will evolve towards an adrenergic phenotype. In the third stage (17-23 GW), we observed the ultimate location of the medulla gland. Both the in situ results and the in vitro experiments indicate that particular procedures need to be implemented prior transplantation of chromaffin cells. First, in order to obtain a large number of immature chromaffin cells, they must be isolated from the intra and extra-adrenal gland and should then be committed towards an adrenergic phenotype in vitro for subsequent use in pain therapy. This strategy is under investigation in our laboratory.

Anomalies of the TCF2 gene are the main cause of fetal bilateral hyperechogenic kidneys

Prenatal discovery of fetal bilateral hyperechogenic kidneys is very stressful for pregnant women and their family, and accurate diagnosis of the cause of the moderate forms of this pathology is very difficult. Hepatocyte nuclear factor-1beta that is encoded by the TCF2 gene is involved in the embryonic development of the kidneys. Sixty-two pregnancies with fetal bilateral hyperechogenic kidneys including 25 fetuses with inaccurate diagnosis were studied. TCF2 gene anomalies were detected in 18 (29%) of these 62 patients, and 15 of these 18 patients presented a complete heterozygous deletion of the TCF2 gene. Family screening revealed de novo TCF2 anomalies in more than half of the patients. TCF2 anomalies were associated with normal amniotic fluid volume and normal-sized kidneys between -2 and +2 SD in all patients except for two sisters. Antenatal cysts were detected in 11 of 18 patients, unilaterally in eight of 11. After birth, cysts appeared during the first year (17 of 18), and in patients with antenatal cysts, the number increased and developed bilaterally with decreased renal growth. In these 18 patients, the GFR decreased with longer follow-up and was lower in patients with solitary functioning dysplastic kidney. Heterozygous deletion of the TCF2 gene is an important cause of fetal hyperechogenic kidneys in this study and showed to be linked with early disease expression. The renal phenotype and the postnatal evolution were extremely variable and need a prospective long-term follow-up. Extrarenal manifestations are frequent in TCF2-linked pathologies. Therefore, prenatal counseling and follow-up should be multidisciplinary.

Renal tubular dysgenesis, a not uncommon autosomal recessive disorder leading to oligohydramnios: Role of the Renin-Angiotensin system

Renal tubular dysgenesis is a clinical disorder that is observed in fetuses and characterized by the absence or poor development of proximal tubules, early onset and persistent oligohydramnios that leads to the Potter sequence, and skull ossification defects. It may be acquired during fetal development or inherited as an autosomal recessive disease. It was shown recently that autosomal recessive renal tubular dysgenesis is genetically heterogeneous and linked to mutations in the genes that encode components of the renin-angiotensin system. This study analyzed the clinical expression of the disease in 29 fetus/neonates from 18 unrelated families and evaluated changes in renal morphology and expression of the renin-angiotensin system. The disease was uniformly severe, with perinatal death in all cases as a result of persistent anuria and hypoxia related to pulmonary hypoplasia. Severe defects in proximal tubules were observed in all fetuses from 18 gestational weeks onward, and lesions also involved other tubular segments. They were associated with thickening of the renal arterial vasculature, from the arcuate to the afferent arteries. Renal renin expression was strikingly increased in 19 of 24 patients studied, from 13 families, whereas no renal renin was detected in four patients from three families. Angiotensinogen and angiotensin-converting enzyme were absent or present in only small amounts in the proximal tubule, in correlation with the severity of tubular abnormalities. No specific changes were detected in angiotensin II receptor expression. The severity and the early onset of the clinical and pathologic expression of the disease underline the major importance of this system in fetal kidney function and development in humans. The identification of the disease on the basis of precise histologic analysis and the research of the genetic defect now allow genetic counseling and early prenatal diagnosis.

Prenatal diagnosis and outcome of congenital splenic cyst: report of two cases

Congenital splenic cyst (CSC) is a rare condition, and only a few cases with prenatal diagnosis and no associated malformation have been reported. Spontaneous regression is possible in case of mild CSC (under 40 mm), but enlargement or secondary complications may lead to surgical treatment. We report, herein, two cases of isolated mild CSC with complete spontaneous postnatal regression.

Cell therapy of pain: Characterization of human fetal chromaffin cells at early adrenal medulla development

Adult adrenal chromaffin cells are being utilized for therapeutic transplantation. With the prospect of using fetal chromaffin cells in pain therapy, we studied their phenotype, proliferative power, function, and growth in vitro and in situ in order to determine the optimal time for implantation. Between 7 and 10 gestational weeks (GW), we isolated, in vitro, two types of chromaffin cells with a noradrenergic phenotype akin to that observed, in situ. Among the adherent chromaffin cells first observed in vitro, only a few samples expressed met-enkephalin, whereas almost all the neurosphere-like colonies, which appeared later, expressed it. However, neither of the two types of populations expressed an adrenergic phenotype in line with that observed in situ. At the upper limits of the voluntary abortion period authorized in France, this phenotype (12 GW) and met-enkephalin expression (13 GW) were evidenced in situ. For the first time in man, we demonstrate the secretion of noradrenaline in vitro by the two populations of cells. Consistent with this result, we also noted dopamine beta hydroxylase (DbetaH) mRNA expression in vitro and in situ within this period. These observations on the expression of these biological factors indicate that 9-10 GW would be the best stage for sampling these cells for preclinical transplantation experiments.

Mutations in genes in the renin-angiotensin system are associated with autosomal recessive renal tubular dysgenesis

Autosomal recessive renal tubular dysgenesis is a severe disorder of renal tubular development characterized by persistent fetal anuria and perinatal death, probably due to pulmonary hypoplasia from early-onset oligohydramnios (Potter phenotype). Absence or paucity of differentiated proximal tubules is the histopathological hallmark of the disease and may be associated with skull ossification defects. We studied 11 individuals with renal tubular dysgenesis, belonging to nine families, and found that they had homozygous or compound heterozygous mutations in the genes encoding renin, angiotensinogen, angiotensin converting enzyme or angiotensin II receptor type 1. We propose that renal lesions and early anuria result from chronic low perfusion pressure of the fetal kidney, a consequence of renin-angiotensin system inactivity. This is the first identification to our knowledge of a renal mendelian disorder linked to genetic defects in the renin-angiotensin system, highlighting the crucial role of the renin-angiotensin system in human kidney development.

Production and characterisation of an antimelanoma monoclonal antibody KBA.62 using a new melanoma cell line reactive on paraffin wax embedded sections

AIMS--To generate new monoclonal antibodies directed against melanoma associated antigens using a new melanoma cell line, KAL. METHODS--The melanoma cell line was established in culture from a lymph node metastasis of malignant melanoma. Normal Balb/c mice were immunised with KAL cells. Splenocytes were used for fusion experiments using standard techniques. Hybridoma supernatants were tested for antibody binding activity using an indirect immunoperoxidase method on frozen sections from KAL tumour cells xenografted onto nude mice and human tonsils. KBA.62 was selected because of its reactivity with melanocytic proliferations on both frozen and paraffin wax sections. RESULTS--On immunoblotting, KBA.62 reacted with three bands of 140, 135 and 128 kD and two weak bands of 88 and 73 kD. In normal human tissues basal melanocytes in the epidermis did not react with this antibody and only occasional labelling of endothelial cells was noted. Of the human tumours, KBA.62 reacted strongly and uniformly with the majority of benign (21/21) and malignant (75/86) melanocytic proliferations. Staining was localised predominantly to the cell membrane with little or no cytoplasmic reactivity. Negative staining was observed in the majority of human non-melanocytic neoplasms, the exceptions being some carcinomas (11/89), particularly the well differentiated squamous cell type. This, however, was not thought to present a diagnostic problem. CONCLUSIONS--KBA.62 appears to be potentially useful in ascertaining the immunomorphological diagnosis of malignant melanoma in routinely processed paraffin wax sections.