LE Cells Research Articles

Aberrant activation of Notch1 signaling in the mouse uterine epithelium promotes hyper-proliferation by increasing estrogen sensitivity.

In mammals, the endometrium undergoes dynamic changes in response to estrogen and progesterone to prepare for blastocyst implantation. Two distinct types of endometrial epithelial cells, the luminal (LE) and glandular (GE) epithelial cells play different functional roles during this physiological process. Previously, we have reported that Notch signaling plays multiple roles in embryo implantation, decidualization, and postpartum repair. Here, using the uterine epithelial-specific Ltf-iCre, we showed that Notch1 signaling over-activation in the endometrial epithelium caused dysfunction of the epithelium during the estrous cycle, resulting in hyper-proliferation. During pregnancy, it further led to dysregulation of estrogen and progesterone signaling, resulting in infertility in these animals. Using 3D organoids, we showed that over-activation of Notch1 signaling increased the proliferative potential of both LE and GE cells and reduced the difference in transcription profiles between them, suggesting disrupted differentiation of the uterine epithelium. In addition, we demonstrated that both canonical and non-canonical Notch signaling contributed to the hyper-proliferation of GE cells, but only the non-canonical pathway was involved with estrogen sensitivity in the GE cells. These findings provided insights into the effects of Notch1 signaling on the proliferation, differentiation, and function of the uterine epithelium. This study demonstrated the important roles of Notch1 signaling in regulating hormone response and differentiation of endometrial epithelial cells and provides an opportunity for future studies in estrogen-dependent diseases, such as endometriosis.

Detection of Antinuclear Antibodies in Canine Serum by Immunoperoxidase in MDCK and Indirect Immunofluorescence in HEp2 Cells

Antinuclear antibodies are found in animals suffering from Systemic Lupus Erythematosus (SLE) and some other diseases, their presence in the blood is determined by antinuclear antibody (ANA) test using indirect immunofluorescence (IF) with HEp2 cells as a substrate. In this work, an immunoperoxidase (IP) assay was developed to evaluate the ANAs in canine sera, using canine kidney cell lines (MDCK) and compared with a commercial immunofluorescence test on Hep2 cells for this system, a fluoresceinated anti-canine Ig antibody was standardized. The study was performed on 50 sera from dogs submitted to the laboratory with different clinical diagnoses of autoimmune-associated diseases. The procedures on both cells were unified to perform comparisons of the reactions, direct sera or at different dilutions were added to a monolayer of permeabilized MDCK cells, followed by a peroxidized anti-canine IgG conjugate, and a substrate for the IP reaction. The same sera were tested on the commercial IF assay on Hep2 cell system. In 22/50 cases, the presence of LE cells in peripheral blood was determined. A high correlation was found in the detection of antinuclear antibodies between both cell lines and techniques, however there were differences in the reaction patterns in the nucleus and cytoplasm between cell lines. The diffuse nuclear pattern observed in MDCK cells was more related to the presence of high percentages of LE cells in peripheral blood. The differences found in the results were possibly associated with the presence of homologous antigens between the MDCK cells and the dog. In addition, the methodology and standardization for the use and interpretation of a reference serum was developed to unify the interpretation criteria in the laboratory.

Megakaryocyte cytoplasmic fragments and ragocytes in the peripheral blood of a domestic cat infected with Anaplasma

In this case report, the author reports three strong and highly unusual changes in the peripheral blood of a domestic cat infected with Anaplasma. A freshly made blood smear from the cat Anaplasma had a shower of about 100 variably large to huge cytoplasmic fragments of megakaryocyte cytoplasm along the feathered edge. These had budding of platelets at their margins. Neutrophils with red cytoplasmic inclusions resembling ragocytes and neutrophils with ingested round inclusions of nuclear material were seen in a 1-day-old EDTA blood sample but not the freshly made blood smear. The cells with nuclear material resembled LE cells or alternatively Tart cells.

SPP1 expression in the mouse uterus and placenta: implications for implantation†.

Secreted phosphoprotein 1 (SPP1, also known as osteopontin) binds integrins to mediate cell-cell and cell-extracellular matrix communication to promote cell adhesion, migration, and differentiation. Considerable evidence links SPP1 to pregnancy in several species. Current evidence suggests that SPP1 is involved in implantation and placentation in mice, but in vivo localization of SPP1 and in vivo mechanistic studies to substantiate these roles are incomplete and contradictory. We localized Spp1 mRNA and protein in the endometrium and placenta of mice throughout gestation, and utilized delayed implantation of mouse blastocysts to link SPP1 expression to the implantation chamber. Spp1 mRNA and protein localized to the endometrial luminal (LE), but not glandular epithelia (GE) in interimplantation regions of the uterus throughout gestation. Spp1 mRNA and protein also localized to uterine naturel killer (uNK) cells of the decidua. Within the implantation chamber, Spp1 mRNA localized only to intermittent LE cells, and to the inner cell mass. SPP1 protein localized to intermittent trophoblast cells, and to the parietal endoderm. These results suggest that SPP1: (1) is secreted by the LE at interimplantation sites for closure of the uterine lumen to form the implantation chamber; (2) is secreted by LE adjacent to the attaching trophoblast cells for attachment and invasion of the blastocyst; and (3) is not a component of histotroph secreted from the GE, but is secreted from uNK cells in the decidua to increase angiogenesis within the decidua to augment hemotrophic support of embryonic/fetal development of the conceptus.

KPNA4 is involved in cataract formation via the nuclear import of p53.

KPNA4 (also called importin-α3) belongs to the importin α adaptor proteins family, which orchestrates classical nuclear transport processes, importin-α/importin-β1 pathway, and involves in cellular homeostasis. Disruption of balanced transport pathways may result in ectopic nuclear proteins and eventually cause diseases, mainly under the situation of cellular stress, such as oxidative stress. Little evidence is available on its cellular functions for high specific expression in lens. We firstly studied the role of KPNA4 in cataract formation. Lens defects were observed at an early age in kpna4 gene knockout zebrafish, generated by the CRISPR/Cas9 system. Those phenotype, including cloudy center part of the lens, via bright field microscopy, and the thinning of the LE layer, wider space between the adjacent LE and LF cells, irregular cells morphology and the increased number of holes inside the LE cells, which were detected by transmission electron microscopy, recapitulate the clinical features of cataract patients. As the p53-specific adaptor of the nuclear import, KPNA4 upregulated with the same pattern of p53 in hydrogen peroxide-induced apoptosis in human lens epithelia cells. Furthermore, the loss of Kpna4 resulted in the accumulation of p53 in the center of lens. Taken together, we showed that KPNA4 was involved in the formation of cataract, likely by mediating p53 nuclear transport.

Utilidad de los estudios en busca de autoinmunidad en pacientes con urticaria crónica espontánea

Chronic spontaneous urticaria (CSU) is a common condition in adults, especially among women; this entity is frequently associated with autoimmune diseases. Our goal is to assess through laboratory studies whether patients with autoimmune CSU presented data. A cross-sectional study of 35 patients was done in the area of Allergy and Immunology at Hospital Juarez de Mexico diagnosed with CSU. We performed the following tests: complete blood count, thyroid antibodies (antiperoxidase and thyroglobulin), antinuclear antibodies, rheumatoid factor, lupus anticoagulant, LE cells Autologous Serum Skin Test (ASST), add (C3 and C4). In addition, we made Helicobacter pylori test, thyroid hormones (T3, T4, TSH) and D-dimer. We evaluated 35 adult patients, 27 female; ASST was positive in 4 patients, negative antinuclear antibodies in all cases, but positive anti thyroid (AAT) antibodies in 4. The LE cell, lupus anticoagulant, complement, dimer D, thyroid and Helicobacter pylori profile were normal or negative and rheumatoid factor was positive in one patient. All AAT-positive patients were women, but 26 of them had negative ASST. The correlation between ASST and AAT was not significant. Most patients were women UCE and only 4 had positive ASST, but this does not correlate with the presence of anti-thyroid antibodies. Most studies were normal, so we suggest not making unnecessary laboratory studies in this disease.

Developmental expression, co-localization and genetic interaction of exocyst component Sec15 with Rab11 during Drosophila development

Sec15, a component of an evolutionarily conserved octomeric exocyst complex, has been identified as an interactor of GTP-bound Rab11 in mammals and Drosophila which shows its role in secretion in yeast and intracellular vesicle transport. Here, we report the expression patterns of Drosophila Sec15 (DSec15) transcript and Sec15 protein during Drosophila development. At early embryonic stages, a profound level of maternally loaded DSec15 transcript and protein is found. At cellular blastoderm cells (stage 5 embryos); the expression is seen in pole cells, apical membrane and sub-apical region. The transcript is predominantly accumulated in mesoderm, tracheal pits, gut, LE cells, trachea, and ventral nerve cord as development proceeds. While, a robust expression of Sec15 is seen in amnioserosa (AS), lateral epidermis (LAE), developing trachea, gut, ventral nerve cord and epithelial cells. During larval development, the transcript is also found in all imaginal discs with a distinguished accumulation in the morphogenetic furrow of eye disc, gut, proventriculus and gastric ceacae, garland cells/nephrocytes, malpighian tubules, ovary and testis. Further, we show that Sec15 co-localizes with Rab11 during Drosophila embryonic and larval development. Finally, using a genetic approach, we demonstrate that Sec15 interacts with Rab11 in producing blister during Drosophila wing development.

Unique epithelial expression of S100A calcium binding protein A7A in the endometrium at conceptus implantation in pigs

ObjectiveS100A7A, a member of the S100 protein family, is involved in various biological processes, including innate immunity, antimicrobial function, and epithelial tumorigenesis. However, the expression and function of S100A7A in the endometrium during the estrous cycle and pregnancy are not well understood in pigs. Therefore, this study determined the expression and regulation of S100A7A at the maternal-conceptus interface in pigs.MethodsWe obtained endometrial tissues from pigs throughout the estrous cycle and pregnancy, conceptus tissues during early pregnancy, and chorioallantoic tissues during mid- to late pregnancy and analyzed the expression of S100A7A in these tissues. We also determined the effects of steroid hormones, estradiol-17β (E2) and progesterone, and interleukin-1β (IL1B) on S100A7A expression in endometrial tissues.ResultsWe found that S100A7A was expressed in the endometrium during the estrous cycle and pregnancy in a pregnancy status- and stage-dependent manner and was localized to endometrial luminal epithelial (LE) and superficial glandular epithelial cells with strong intensity in LE cells on day 12 of pregnancy. Early stage conceptuses and chorioallantoic tissues from day 30 to term pregnancy also expressed S100A7A. The expression of S100A7A was increased by E2 and IL1B in endometrial tissues.ConclusionS100A7A was expressed at the maternal-conceptus interface at the initiation of implantation in response to conceptus-derived estrogen and IL1B and could be a unique endometrial epithelial marker for conceptus implantation in pigs. These findings provide an important insight into the understanding of conceptus-endometrial interactions for the successful establishment of pregnancy in pigs.

Cellular events during ovine implantation and impact for gestation.

The establishment of pregnancy in sheep includes elongation of the blastocyst into a filamentous conceptus, pregnancy recognition, production of histotroph, attachment of the conceptus to the endometrium for implantation, and development of synepitheliochorial placentation. These processes are complex, and this review describes some of the molecular events that underlie and support successful pregnancy. The free-floating sheep blastocyst elongates into a filamentous conceptus and metabolizes, or is responsive to, molecules supplied by the endometrium as histotroph. Amongst these molecules are SPP1, glucose and fructose, and arginine that stimulate the MTOR nutrient sensing system. The placental trophectoderm of elongating conceptuses initiate pregnancy recognition and implantation. The mononucleate cells of the trophectoderm secrete IFNT, which acts on the endometrial LE to block increases in estrogen receptor α to preclude oxytocin receptor expression, thereby preventing oxytocin from inducing luteolytic pulses of PGF2α. In addition, IFNT increases expression of IFN stimulated genes in the endometrial stroma, including ISG15, a functional ubiquitin homologue. Implantation is the initial step in placentation, and includes sequential pre-contact, apposition, and adhesion phases. Implantation in sheep includes downregulation of Muc1 and interaction of GLYCAM1, galectin 15 (LGALS15) and SPP1 with lectins and integrins (αvβ3). Sheep have synepitheliochorial placentation in which mononucleate trophectoderm cells fuse to form binucleate cells (BNCs). BNCs migrate and fuse with endometrial LE cells to form trinucleate syncytial cells, and these syncytia enlarge through continued BNC fusion to form syncytial plaques that form the interface between endometrial and placental tissues within the placentome. The placentae of sheep organize into placentomal and interplacentomal regions. In placentomes there is extensive interdigitation of endometrial and placental tissues to provide hemotrophic nutrition to the fetus. In interplacentomal regions there is epitheliochorial attachment of endometrial LE to trophectoderm, mediated through focal adhesion assembly, and areolae that take up histotroph secreted by endometrial GE.

Association of Acute Myeloid Leukemia and Systemic Lupus Erythematosus: A Case Report

Systemic lupus erythematosus is an autoimmune Inflammatory disease that can affect multiple systems and organs of the body including skin, kidneys, lungs, joints and nervous system.Some previous studies up light thatSLE was associated with increased risk of Acute leukemia (SIR = 2.3). The incidence ofthe association of AMLand SLE is not known but there are few case reports in literature. The aim of this report was to up light the difficulties wich occurred in the diagnosis and the management of acute myeloid leukemia in patient with systemic lupus erythematosus. Patient, 43 years old, diabetic treat withinsulin, wichsister is followed for Behcet's disease, was admited for AML with trisomy of chromosome 4 and 8 and thrombophlebitis of the superior sagittal sinus, Chest CT-Scan showed minimal bilateral pleural effusion. She was treated according to Morocco National protocol AML-MA-2011. CT-Scan was done atday 12 ofchemotherapy and noticedthe persistance of the minimal bilateral pleural effusion.At day 19 the patient presentedmalar rash, and right axillary adenitis. The biopsy of the adenitis show the presence of LE cells. According to internal physician recommendations we add steroids to the treatement. The cough and fever deasapear. The CT-scan for control was normal after two weeks of steroids. Patient is in complete remission after induction I. After a following-up of five months, the patient still well,but present severy infections during chemotherapy cycles and a bad tolerance for the treatement. The association SLE-AML is rare. The diagnosis of the association SLE-AML is difficult. It is management is also difficult according to commorbidity, severy infectious because of dicline of immunity, and less tolerance to AML chemotherapy.

Intracytoplasmic basophilic bodies in leukocytes in an HIV patient with pleural and pericardial effusion led to unexpected diagnosis

Human immunodeficiency virus (HIV) infections are declining worldwide; however, there are still >1.2 million HIV-infected people in the USA and ~6700 deaths/year can be directly attributed to HIV-related diseases. Opportunistic infections, Kaposi sarcoma, and non-Hodgkin lymphomas are always high in the differential diagnosis of HIV patients with systemic symptoms; however, causes of morbidity and mortality in HIV patients on highly active antiretroviral therapy are now approaching those of the general population. We present a case of an HIV patient who presented with B symptoms and body effusions. Diagnostic work-up geared towards infectious and neoplastic diseases led to the identification of intra- and extracellular rounded basophilic bodies in bone marrow and pleural effusion that were recognized as LE cells and allowed the diagnosis of systemic lupus erythematosus (SLE). We discuss the historical aspects of LE cell discovery, recent advances about their nature, ramifications of concurrent HIV-infection, and SLE and provide reference images of a finding that was originally described in bone marrow biopsies, but that nowadays has been nearly forgotten due to the development of alternative diagnostic tests.

“Lupoid hepatitis” in SLE patients and mice with experimental lupus

The unusual subset of patients with severe hepatitis, hypergammaglobulinemia, arthritis, and LE cells in the blood reported by Henry Kunkel and others suggested to these investigators that “lupoid” hepatitis might share pathogenic mechanisms with SLE. More than half a century later, the etiology of autoimmune hepatitis remains unclear. The occurrence of autoimmune hepatitis in a small fraction (about 3%) of SLE patients in our lupus cohort and in two mouse models of SLE supports their conclusion that lupoid hepatitis may be share pathogenic mechanisms with SLE. The development of autoimmune hepatitis in mice with pristane-induced lupus provides an opportunity to further explore the potential link between these two autoimmune disorders.

Epidermal growth factor: Porcine uterine luminal epithelial cell migratory signal during the peri-implantation period of pregnancy

The majority of early conceptus mortality in pregnancy occurs during the peri-implantation period, suggesting that this period is important for conceptus viability and the establishment of pregnancy. Successful establishment of pregnancy in all mammalian species depends on the orchestrated molecular events that transpire at the conceptus-uterine interface during the peri-implantation period of pregnancy. This maternal-conceptus interaction is especially crucial in pigs because they have a non-invasive epitheliochorial placentation during a protracted peri-implantation period. During the pre-implantation period of pregnancy, conceptus survival and the establishment of pregnancy depend on the developing conceptus receiving an adequate supply of histotroph which contains a wide range of nutrients and growth factors. Evidence links epidermal growth factor (EGF) to embryogenesis or implantation in various mammalian species. EGF exhibits potential growth-promoting activities on the conceptus and endometrium; however, in the case of pigs, little is known its functions, especially their regulatory mechanisms at the maternal-conceptus interface. EGF receptor (EGFR) mRNA and protein are abundant in endometrial luminal (LE) and glandular (GE) epithelia and conceptus trophectoderm on Days 13–14 of pregnancy, suggesting that EGF provides an autocrine signal to uterine LE and GE just prior to implantation. Therefore, the objectives of this study were to determine: 1) the potential intracellular signaling pathways responsible for the activities of EGF in porcine uterine LE (pLE) cells; and 2) the changes in cellular activities induced by EGF. EGF treatment of pLE cells increased the abundance of phosphorylated (p)-ERK1/2, p-P70RSK and p-RPS6 compared to that for control cells. Furthermore, EGF-stimulated phosphorylation of ERK1/2 MAPK was inhibited in pLE cells transfected with an EGFR siRNA compared with control siRNA-transfected pLE cells. Moreover, EGF stimulated migration of pLE cells, but this stimulatory effect was blocked by U0126, a pharmacological inhibitor or ERK1/2 MAPK. Collectively, these results provide new insights into mechanisms whereby EGF regulates development of the peri-implantation uterine LE at the fetal–maternal interface. These results indicate that endometrial- and/or conceptus derived EGF effects migration of uterine LE and that those stimulatory effects are regulated via the ERK1/2 MAPK pathway during early pregnancy in pigs.

The Role of Cell Death in the Pathogenesis of SLE: Is Pyroptosis the Missing Link?

Systemic lupus erythematosus (SLE) is a prototypic autoimmune disease characterized by the production of antinuclear antibodies (ANAs) in association with systemic inflammation and organ damage. In addition to genetic factors, a contribution of infection to disease induction has been proposed. In the pathogenesis of lupus, immune complexes of ANAs with nuclear antigens can form and both deposit in the tissue and stimulate cytokine production to intensify inflammation. As such, the extracellular release of nuclear antigens to form pathogenic immune complexes is an important step in the pathway to disease. This release has been considered the consequence of cell death, with apoptotic cells the relevant source of nuclear material. While apoptosis could serve this role, other death forms may act similarly. Among these death forms, pyroptosis, which can be induced by inflammasome activation during infection, has features suggesting involvement in lupus. Thus, unlike apoptosis, pyroptosis is a pro-inflammatory process. Furthermore, pyroptosis leads to the release of intracellular contents including HMGB1 and ATP, both of which can act as DAMPs (deathassociated molecular patterns) to stimulate further inflammation. Importantly, pyroptosis can lead to the release of intact nuclei, suggesting a relationship to events in the formation of LE cells. While the role of pyroptosis in SLE is hypothetical at this time, further analysis of this death form should provide new insights into lupus pathogenesis and provide the missing link between infection and the initiation of lupus by products of dead and dying cells.

Characterization of transmembrane auxin transport in Arabidopsis suspension-cultured cells

Polar auxin transport is a crucial process for control and coordination of plant development. Studies of auxin transport through plant tissues and organs showed that auxin is transported by a combination of phloem flow and the active, carrier-mediated cell-to-cell transport. Since plant organs and even tissues are too complex for determination of the kinetics of carrier-mediated auxin uptake and efflux on the cellular level, simplified models of cell suspension cultures are often used, and several tobacco cell lines have been established for auxin transport assays. However, there are very few data available on the specificity and kinetics of auxin transport across the plasma membrane for Arabidopsis thaliana suspension-cultured cells. In this report, the characteristics of carrier-mediated uptake (influx) and efflux for the native auxin indole-3-acetic acid and synthetic auxins, naphthalene-1-acetic and 2,4-dichlorophenoxyacetic acids (NAA and 2,4-D, respectively) in A. thaliana ecotype Landsberg erecta suspension-cultured cells (LE line) are provided. By auxin competition assays and inhibitor treatments, we show that, similarly to tobacco cells, uptake carriers have high affinity towards 2,4-D and that NAA is a good tool for studies of auxin efflux in LE cells. In contrast to tobacco cells, metabolic profiling showed that only a small proportion of NAA is metabolized in LE cells. These results show that the LE cell line is a useful experimental system for measurements of kinetics of auxin carriers on the cellular level that is complementary to tobacco cells.

Expression of Signaling Components in Embryonic Eyelid Epithelium

Closure of an epithelium opening is a critical morphogenetic event for development. An excellent example for this process is the transient closure of embryonic eyelid. Eyelid closure requires shape change and migration of epithelial cells at the tip of the developing eyelids, and is dictated by numerous signaling pathways. Here we evaluated gene expression in epithelial cells isolated from the tip (leading edge, LE) and inner surface epithelium (IE) of the eyelid from E15.5 mouse fetuses by laser capture microdissection (LCM). We showed that the LE and IE cells are different at E15.5, such that IE had higher expression of muscle specific genes, while LE acquired epithelium identities. Despite their distinct destinies, these cells were overall similar in expression of signaling components for the “eyelid closure pathways”. However, while the LE cells had more abundant expression of Fgfr2, Erbb2, Shh, Ptch1 and 2, Smo and Gli2, and Jag1 and Notch1, the IE cells had more abundant expression of Bmp5 and Bmpr1a. In addition, the LE cells had more abundant expression of adenomatosis polyposis coli down-regulated 1 (Apcdd1), but the IE cells had high expression of Dkk2. Our results suggest that the functionally distinct LE and IE cells have also differential expression of signaling molecules that may contribute to the cell-specific responses to morphogenetic signals. The expression pattern suggests that the EGF, Shh and NOTCH pathways are preferentially active in LE cells, the BMP pathways are effective in IE cells, and the Wnt pathway may be repressed in LE and IE cells via different mechanisms.

Role Of Tumor Necrosis Factor α In Bone Marrow Niche Dysfunction Of Patients With Systemic Lupus Erythematosus (SLE)

Objectives and backgroundSLE is a chronic systemic autoimmune disorder associated with autoantibodies and cytopenias. There are few studies of the pathogenesis of anemia of chronic inflammation in lupus. This study addresses the pathogenesis of the hematological manifestations of lupus. We have shown that SLE bone marrow (BM) exhibits striking death of niche and hematopoietic cells associated with tumor necrosis factor-α (TNFα) over-production. Here, we further examined the pathogenesis of hematological BM niche dysfunction. MethodsPathology records over the past 10 years from the University of Florida were reviewed and BM aspirates/core biopsies from 6 SLE patients were identified for further study. Wright-Giemsa stained BM aspirate smears and cytospin preparations, hematoxylin and eosin (H&E)-stained and reticulin stained BM core biopsies were reviewed. Immunohistochemistry (IHC) for TNFα, cleaved caspase-3, and CD71 was performed on core biopsies and expression levels were quantified morphometrically. BM specimens from individuals undergoing staging for lymphoma were selected as controls. ResultsFive of 6 SLE patients had nephritis and 3 were direct Coombs+ (one with hemolytic anemia). Mean hemoglobin was 9.1g/dL in SLE patients and 11.9g/dL in controls. Mean WBC was 3800/mm3 in patients and 8200/mm3 in controls, and mean platelet counts were 133,000/mm3 and 258,000/mm3, respectively. BM aspirates exhibited numerous apoptotic cells, erythroid dyspoiesis, plasmacytosis, hemophagocytosis, and phagocytosis of nuclear material by mature neutrophils (LE cells). Numerous LE cells were seen in 5/6 SLE BM aspirates. Compared to normal BM biopsies, SLE BM biopsies exhibited hypocellularity, erythroid dyspoiesis, polyclonal plasmacytosis, mild reticulin fibrosis, BM stromal damage/disorganization and 3 out of 6 with interstitial lymphoid aggregates. IHC with anti-cleaved caspase-3 antibodies, a specific marker of cell death, revealed numerous caspase-3+ cells in a range of 20-40% of total BM cells in contrast to control BMs of <5%. Interestingly, a large majority of osteoblasts or lining cells in BM osteal niches were caspase-3+ in SLE BM, whereas caspase-3+ cells were rare in control BM biopsies. Using double IHC (TUNEL assay plus anti-CD71 or myeloperoxidase antibodies), prominent apoptotic erythroid precursors with less extensive cell death of the myeloid and megakaryocytic lineages was found in SLE BM core biopsies. In SLE, caspase-3+ cells occupied 9-12% of the total BM area vs. 1-2% in control BM (p<0.001). As TNFα promotes Fas-mediated apoptosis and may damage hematopoietic precursors and/or stromal cells, we examined its production in SLE BM. IHC with anti-TNFα antibodies revealed intense intra- and extracellular staining surrounding neutrophils and monocytes, and the extent of TNFα staining was dramatically higher in SLE patients' BM biopsies than in controls. Staining was particularly intense adjacent to presumptive osteoblasts lining the surface of bone trabeculae, though there also was staining in interstitial regions. There was little TNFα staining of control BM. Morphometric analysis revealed 10-18% of the area in SLE BM intensely stained with anti-TNFα vs. 1-3.5% in controls (P < 0.001, Student t-test), suggesting that TNFα overproduction may cause BM niche dysfunction. ConclusionBM TNFα-mediated niche cell apoptosis is likely to be involved in the pathogenesis of SLE-associated hematological abnormalities. Disclosures:No relevant conflicts of interest to declare.

Erratum to: Magnetite induces oxidative stress and apoptosis in lung epithelial cells

P. Ravichandran R. Gopikrishnan S. Biradar V. Goornavar G. T. Ramesh J. C. Hall (&) Molecular Toxicology Laboratory, Department of Biology, Center for Biotechnology & Biomedical Sciences, Norfolk State University, Norfolk, VA 23504, USA e-mail: jchall@nsu.edu Fig. 5 b LE cells were seeded equally and exposed to magnetite (1, 10, and 20 lg), cultured for 24 h and live and dead cells were visualized based on dye-uptake method and photographed. Dead cells were counted, and % of dead cells were calculated and shown below

A needle in a hay stack: the identification of le cells in pleural fluid cytology leading to a diagnosis of systemic lupus erythematosus

The diagnosis of systemic lupus erythematosus (SLE), a chronic inflammatory autoimmune disorder, is usually made by a combination of physical and laboratory findings including autoimmune se-rology. Pulmonary and pleural involvement in SLE is common and the finding of LE cells in pleural fluid cytology is highly specific for SLE. LE cells are neutrophils that contain phagocytosed debris from dead or injured cells that have been targeted by anti-DNA antibodies. We present a 26-year-old female with known Sjogren’s syndrome who presented with right-sided pneumonia and pleural effusion. Cytological examination revealed an exudative pleural effusion within which occasional LE cells were identified, leading to the diagnosis of SLE. This case demonstrates the importance of intense screening of cytological samples in identifying a vital clue to the diagnosis of SLE.

LE Cells in Pleural Fluid

Altit, Gabriel MDCM*; Brochu, Pierre MD†; Jacob, Sheila V. MD‡; Buithieu, Maria MD* Author Information