Overexpression of hsa-miR-125b during osteoblastic differentiation does not influence levels of Runx2, osteopontin, and ALPL gene expression.

Multipotent mesenchymal stromal cells (MSCs) were first isolated from bone marrow and then from various adult tissues including placenta, cord blood, deciduous teeth, and amniotic fluid. MSCs are defined or characterized by their ability to adhere to plastic, to express specific surface antigens, and to differentiate into osteogenic, chondrogenic, adipogenic, and myogenic lineages. Although the molecular mechanisms that control MSC proliferation and differentiation are not well understood, the involvement of microRNAs has been reported. In the present study, we investigated the role of miR-125b during osteoblastic differentiation in humans. We found that miR-125b increased during osteoblastic differentiation, as well as Runx2 and ALPL genes. To study whether the gain or loss of miR-125b function influenced osteoblastic differentiation, we transfected MSCs with pre-miR-125b or anti-miR-125b and cultured the transfected cells in an osteoblastic differentiation medium. After transfection, no change was observed in osteoblastic differentiation, and Runx2, OPN, and ALPL gene expression were not changed. These results suggest that the gain or loss of miR-125b function does not influence levels of Runx2, OPN, and ALPL during osteoblastic differentiation.

Overexpression of hsa-miR-125b during osteoblastic differentiation does not influence levels of Runx2, osteopontin, and ALPL gene expression

Multipotent mesenchymal stromal cells (MSCs) were first isolated from bone marrow and then from various adult tissues including placenta, cord blood, deciduous teeth, and amniotic fluid. MSCs are defined or characterized by their ability to adhere to plastic, to express specific surface antigens, and to differentiate into osteogenic, chondrogenic, adipogenic, and myogenic lineages. Although the molecular mechanisms that control MSC proliferation and differentiation are not well understood, the involvement of microRNAs has been reported. In the present study, we investigated the role of miR-125b during osteoblastic differentiation in humans. We found that miR-125b increased during osteoblastic differentiation, as well as Runx2 and ALPL genes. To study whether the gain or loss of miR-125b function influenced osteoblastic differentiation, we transfected MSCs with pre-miR-125b or anti-miR-125b and cultured the transfected cells in an osteoblastic differentiation medium. After transfection, no change was observed in osteoblastic differentiation, and Runx2, OPN, and ALPL gene expression were not changed. These results suggest that the gain or loss of miR-125b function does not influence levels of Runx2, OPN, and ALPL during osteoblastic differentiation.

Papel de la proteómica en la identificación de proteínas diferenciales en pacientes con SAHS / No disponible

Objetivo: Se diseña un estudio con el objetivo de valorar el papel de la proteómica en la identificación de proteínas diferenciales en pacientes con SAHS. Pacientes y métodos: Fueron incluidos 37 enfermos con sintomatología sugestiva de SAHS y un IAH ≥ 5 y un grupo control compuesto por 18 sujetos roncadores, emparejados por IMC, género y edad con el grupo con SAHS en los que se descartó un SAHS (IAH < 5). En ambos grupos se excluyeron a los sujetos que estaban diagnosticados de enfermedad crónica avanzada. En primer lugar se efectuó electroforesis bidimensional que comparó los geles de ambos grupos y estableció los spots diferenciales (sobreexpresión > 2,5 veces el grupo control y subexpresión < 0,5 veces por debajo del grupo control). Posteriormente se realizó espectrometría de masas mediante MALDI /TOF-TOF (matrix laser assisted desorption- time of flight).Resultados: Respecto al grupo control, IAH = 3,5 (3-4,1), en los enfermos con SAHS, IAH = 53 (27-74), mediante MALDI/TOF-TOF se identificó una proteína sobreexpresada, la haptoglobina que se ha relacionado con mayor riesgo vascular en pacientes con SAHS. Igualmente se identificaron dos proteínas subexpresadas, la albúmina y serotransferrina, proteínas que pueden facilitar una disminución de las defensas antioxidantes en el SAHS. Conclusiones: Se aporta el primer perfil proteómico diferencial en pacientes adultos con SAHS. Se demuestra la validez de la proteómica para identificar un conjunto de proteínas diferenciales que puedan ser útiles para el diagnóstico o para establecer un perfil de riesgo vascular (AU)

Objective: a study was designed to assess the role of proteomics in the identification of differential proteins in patient with obstructive sleep apnea-hypopnea syndrome (OSAH). Patients and methods: Thirty seven patients with symptoms suggestive of OSAH and a apnea-hypopnea index (AHI) ≥ 5 were included in the study, and a control group was made up of 18 snorers, matched for BMI, gender and age with the OSAH group in which one OSAH was discarded (AHI < 5). Subjects diagnosed with advanced chronic disease were excluded from both groups. First, two-dimensional electrophoresis was performed, which compared the gels of both groups and established the differential spots (over-expression > 2.5 times the control group and under-expression < 0.5 times below the control group). Subsequently, a mass spectrometry was performed by means of MALDI / TOF-TOF (matrix laser assisted desorption - time of flight). Results: Regarding the control group, mean AHI = was 3.5 (3-4.1), and in those affected with OSAH it was, AHI = 53 (27-74). , Aan over-expressed protein, haptoglobin, was identified by means of MALDI/TOF-TOF, which has been related with a greater vascular risk in patient with OSAH. Likewise, two under-expressed proteins, albumin and serotransferrin, were identified, proteins that can facilitate a decrease of the anti-oxidant defences in OSAH. Conclusions: An initial differential proteomic profile in mature patients with OSAH was found. The legitimacy of proteomics to identify a group of differential proteins that could be useful to diagnosis or establish a profile of vascular risk has been demonstrated (AU)

N-terminally truncated GADD34 proteins are convenient translation enhancers in a human cell-derived in vitro protein synthesis system.

Human cell-derived in vitro protein synthesis systems are useful for the production of recombinant proteins. Productivity can be increased by supplementation with GADD34, a protein that is difficult to express in and purify from E. coli. Deletion of the N-terminal 120 or 240 amino acids of GADD34 improves recovery of this protein from E. coli without compromising its ability to boost protein synthesis in an in vitro protein synthesis system. The use of N-terminally truncated GADD34 proteins in place of full-length GADD34 should improve the utility of human cell-based cell-free protein synthesis systems.

Gadd45 beta forms a homodimeric complex that binds tightly to MKK7.

Gadd45 alpha, beta, and gamma proteins, also known as growth arrest and DNA damage-inducible factors, have a number of cellular functions, including cell-cycle regulation and propagation of signals produced by a variety of cellular stimuli, maintaining genomic stability and apoptosis. Furthermore, Gadd45 beta has been indicated as a major player in the endogenous NF-kappaB-mediated resistance to apoptosis in a variety of cell lines. In fibroblasts this mechanism involves the inactivation of MKK7, the upstream activator of JNK, by direct binding within the kinase ATP pocket. On the basis of a number of experimental data, the structures of Gadd45 beta and the Gadd45 beta-MKK7 complex have been predicted recently and data show that interactions are mediated by acidic loops 1 and 2, and helices 3 and 4 of Gadd45 beta. Here, we provide further evidence that Gadd45 beta is a prevailingly alpha-helical protein and that in solution it is able to form non covalent dimers but not higher-order oligomers, in contrast to what has been reported for the homologous Gadd45 alpha. We show that the contact region between the two monomers is comprised of the predicted helix 1 (residues Q17-Q33) and helix 5 (residues K131-R146) of the protein, which appear to be antiparallel and to form a large dimerisation surface not involved in MKK7 recognition. The results suggest the occurrence of a large complex containing at least an MKK7-Gadd45 beta:Gadd45 beta-MKK7 tetrameric unit whose complexity could be further increased by the dimeric nature of the isolated MKK7.

Zonal hierarchy of differentiation markers and nestin expression during oval cell mediated rat liver regeneration.

Oval cells constitute a heterogeneous population of proliferating progenitors found in rat livers following carcinogenic treatment (2-acetylaminofluorene and 70% hepatectomy). The aim of this study was to investigate the cellular pattern of various differentiation and cell type markers in this model of liver regeneration. Immunophenotypic characterisation revealed at least two subtypes emerging from the portal field. First, a population of oval cells formed duct-like structures and expressed bile duct (CD49f) as well as hepatocytic markers (alpha-foetoprotein, CD26). Second, a population of non-ductular oval cells was detected between and distally from the ductules expressing the neural marker nestin and the haematopoietic marker Thy1. Following oval cell isolation, a subset of the nestin-positive cells was shown to co-express hepatocytic and epithelial markers (albumin, CD26, pancytokeratin) and could be clearly distinguished from anti-desmin reactive hepatic stellate cells. The gene expression profiles (RT-PCR) of isolated oval cells and oval cell liver tissue were found to be similar to foetal liver (ED14). The present results suggest that the two oval cell populations are organised in a zonal hierarchy with a marker gradient from the inner (displaying hepatocytic and biliary markers) to the outer zone (showing hepatocytic and extrahepatic progenitor markers) of the proliferating progeny clusters.

Alteraciones de los fenómenos de neuroplasticidad en las enfermedades de Alzheimer y Creutzfeldt-Jakob. Interrelaciones con fenómenos involutivos / Neuroplasticity changes in Alzheimer´s and Creutztfeldt-Jakob´s Diseases. Relationships to involutive phenomena

Se ha postulado que en las enfermedades neurodegenerativas,las alteraciones en los fenómenos de neuroplasticidady adaptación tienen una función muy importante,como desencadenante o motor del curso patogénico delas enfermedades. Para aclarar este extremo se ha llevadoa cabo un estudio morfohistoquímico comparativo en lacorteza cerebral prefrontal y en la corteza cerebelosa(neocerebelo) de cerebros de enfermos de Alzheimer yCreutzfeldt-Jakob (EA y ECJ). Se han analizado las variacionesen marcadores supuestamente relacionados confenómenos de neuroplasticidad sináptica (Drebrina, SNAP-25), factor de activación nuclear (NF kappa Beta -NFkB) eisoforma neuronal de la óxido nítrico sintasa (nNOS) juntoa marcardores de neuropatología (acumulación de proteínasbeta –amiloide en EA y PrPsc en ECJ-, reacción microgliale inducción de enzimas pro-inflamatorias iNOS yciclo-oxigenasa 2 (COX-2). Los resultados han mostradograndes variaciones de los marcadores entre ambos procesospatológicos, entre las cortezas cerebral y cerebelosa,entre diferentes áreas de esas regiones y entre diferentesestirpes neuronales y gliales. El significado de algunosde los marcadores (NFkB, nNOS, proteínas sinápticas) puede ser variable (plástico o involutivo) según los casos(enfermedad, región, factores). La neuroplasticidad disminuyede manera diversa según las áreas cerebrales y susrelaciones con las manifestaciones neuropatológicas tambiénson variables, aunque son manifiestos fenómenos deneuroplasticidad/adaptación en muchas áreas y neuronas.Se concluye que la activación de los supuestos marcadoresde neuroplasticidad en fases avanzadas de la enfermedad,con una idea terapéutica, puede activar fenómenosinvolutivos en algunas regiones o neuronas del cerebro

Changes in neuroplasticity and neuronal adaptativemechanisms have been postulated as origin and/or mainpathophysiological factor in neurodegenerative diseases.To analyze these theories, a comparative morphohistochemicalstudy on the cerebral (prefrontal) and cerebellar(neocerebellar) cortex from Alzheimer´s (AD) and Creutzfeldt-Jakob (CJD) post-mortem brains has been carriedout. Variations in putative markers of neuroplasticity andneuronal adaptation (synaptic proteins such as drebrinand SNAP-25; nuclear factor NF kappa Beta –NFkB-; neuronalisoform of oxide nitric synthase -nNOS) have beenstudied in close association with neuropathological markers(beta-protein deposition – amyloid in AD and PrPsc inCJD-; microglial activation, induction of iNOS and cyclooxygenase2 –COX-2). Results have shown sharp variationsin these markers when compared AD and CJD; cerebraland cerebellar cortex; different areas of these anatomicalregions; and different sets of neurons and glial cells.The meaining of somme of these markers (NFkB; nNOS;synaptic proteins) could be variable (plastic/adaptative orinvolutive), depending on different factors (disease, anatomicalregion, general or local factors, etc.). Neuroplasticity is evident in several brain regions or neurons, but this neuronalfeature decreases in different form depending alsoon the disease and the anatomical region. Their relationshipsto the neuropathological findings were also variable.In conclusion, the activation of these putative markers ofneuroplasticity, considering as therapeutical targets, inadvanced steps of the diseases, could activate neuronalinvolutive phenomena in several regions or neurons

El diagnóstico microbiológico independiente del cultivo en la candidiasis invasora. Importancia de los marcadores fúngicos / Microbiological non-culture methods for the diagnosis of invasive candidiasis: usefulness of surrogate markers

La utilidad de los marcadores serológicos en el diagnóstico de la candidiasisinvasora pasa por detectar la infección por las distintas especies del géneroCandida y diferenciar cuando estos hongos se encuentran como colonizadores ycuando se encuentran causando una infección invasora. Esta diferenciación seha intentado detectando antígenos, anticuerpos y otros componentes deCandida en el suero de los pacientes. En este artículo se revisan los antígenos,anticuerpos y otros componentes de Candida que son de utilidad en el diagnósticode laboratorio de la candidiasis invasora en pacientes críticos no neutropénicos

The usefulness of surrogate markers in the diagnosis of invasive candidiasis isbased on their ability to detect the infection caused by the different Candida spp.and to differentiate when the fungus is a colonizer or it is causing an invasivedisease. This differentiation has been tried by detecting antigens, antibodies andother Candida components in the patient's sera. In this paper we will review theantigens, antibodies and other Candida components which may be useful in thelaboratory diagnosis of invasive candidiasis in the non-neutropenic critically illpatient

Anticuerpos anti-micelio de Candida albicans en dos pacientes de cuidados intensivos con candidiasis invasora / Antibodies to Candida albicans germ tubes in two intensive care patients with invasive candidiasis

Se describen dos casos de candidiasis invasora en pacientes de una Unidad deCuidados Intensivos en los que se muestra la utilidad de los anticuerpos frente ala fase micelial de Candida albicans en el diagnóstico de la candidiasis invasoray en el seguimiento del tratamiento antifúngico

Two cases of invasive candidiasis in intensive care patients are presented toillustrate the usefulness of detection of antibodies to Candida albicans germtubes in the diagnosis of invasive candidiasis and in monitoring the efficacy ofthe antifungal treatment

Evaluation of 3 different tests for the detection of stool antigens to confirm Helicobacter pylori eradication after treatment. A pilot study

Introducción: Recientemente se han desarrollado varios métodos diagnósticos nuevos dirigidos a la detección de antígenos de Helicobacter pylori en las heces. El objetivo de nuestro estudio ha sido la evaluación de la precisión de 3 pruebas distintas de detección de antígenos en heces para confirmar la erradicación de H. pylori. Pacientes y métodos: Se administró tratamiento de erradicación de H. pylori a 26 pacientes. La erradicación se confirmó 6-8 semanas después mediante la prueba de urea marcada con 13C en el aire espirado, con análisis de muestras de heces mediante una prueba policlonal (Premier-Platinum-HpSATM), una prueba monoclonal (Amplified-IDEIA®-HpStARTM) y una prueba rápida (ImmunoCard-STAT-HpSATM). Resultados: La erradicación de H. pylori se confirmó en el 85% de los casos. Los porcentajes correspondientes a la sensibilidad, la especificidad, el valor predictivo positivo y el valor predictivo negativo de la prueba policlonal fueron del 25, el 91, el 33 y el 87%. Los resultados correspondientes a la prueba monoclonal utilizando el umbral recomendado por el fabricante fueron del 100, el 46, el 25 y el 100%. No obstante, el mejor umbral considerado en nuestro estudio dio lugar a una sensibilidad del 100% y una especificidad del 95%. El área bajo la curva de rendimiento diagnóstico (receiver operating characteristics) respecto a las pruebas policlonal y monoclonal fue de 0,65 y 0,95, respectivamente. Los resultados correspondientes a la sensibilidad, la especificidad, el valor predictivo positivo y el valor predictivo negativo de la prueba rápida fueron del 75, el 90, el 60 y el 95%. Conclusión: Para la confirmación de la erradicación de H. pylori tras el tratamiento no se pueden recomendar la prueba policlonal ni la prueba rápida de detección de antígenos en heces. La prueba monoclonal muestra una precisión diagnóstica mayor, aunque son necesarios nuevos estudios para poder recomendar definitivamente su aplicación de cara a la confirmación de la erradicación de H. pylori

Introduction: Recently, several new diagnostic methods aimed to detect Helicobacter pylori stool antigens have been developed. Our aim was to evaluate the accuracy of 3 different stool tests to confirm H. pylori eradication. Patients and methods: Twenty-six patients received H. pylori eradication treatment. Eradication was confirmed with 13C-urea breath test 6-8 weeks later, when stool samples were analyzed by polyclonal (Premier-Platinum-HpSATM), monoclonal (Amplified-IDEIATM-HpStARTM), and rapid test (ImmunoCard-STAT-HpSATM). Results: H. pylori was eradicated in 85% of the cases. Sensitivity, specificity, positive predictive value and negative predictive value with the polyclonal test were: 25%, 91%, 33% and 87%. Corresponding results with the monoclonal test, using the cut-off point recommended by the manufacturer, were 100%, 46%, 25% and 100%. However, the best cut-off point in our study had 100% sensitivity and 91% specificity. The area under ROC curve for the polyclonal and the monoclonal tests was 0.65 and 0.95. Diagnostic accuracy with the rapid test was 75%, 90%, 60% and 95%. Conclusion: Neither the polyclonal stool antigen test nor the rapid stool antigen test can be recommended to confirm H. pylori eradication after treatment. The monoclonal test has better diagnostic accuracy, although more studies are necessary to definitively recommend its use for the confirmation of H. pylori eradication success

Identification of Lewis x structures of the cell adhesion molecule CEACAM1 from human granulocytes.

Carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) is expressed on epithelia, blood vessel endothelia, and leukocytes. A variety of physiological functions have been assigned to CEACAM1. It is involved in the formation of glands and blood vessels, in immune reactions, and in the regulation of tumor growth. As a homophilic and heterophilic adhesion receptor, it signals through different cellular pathways. The existence of special oligosaccharide structures such as Lewis x or sialyl-Lewis x glycans within this highly glycosylated protein has been postulated, but chemical proof is missing so far. Because such structures are known to be essential for different cell-cell recognition and adhesion processes, characterizing the CEACAM1 glycan structure is of pivotal importance in revealing the biological function of CEACAM1. We examine the terminal glycosylation pattern of CEACAM1 from human granulocytes, focusing on Lewis x epitopes. Lewis x-specific antibodies react with immunoaffinity-purified native CEACAM1. Antibody binding was completely abolished by treatment with fucosidase III, confirming a terminal alpha(1-3,4) fucose linkage to the N-acetylglucosamine of lactosamine residues, a key feature of Lewis epitopes. To verify these data, MALDI-TOF MS analysis after stepwise exoglycosidase digestion of the CEACAM1 N-glycan mixture was performed. A complex mixture of CEACAM1-bound oligosaccharides could be characterized with an unusually high amount of fucose. The sequential digestions clearly identified several different Lewis x glycan epitopes, which may modulate the cell adhesive functions of CEACAM1.

Mapping of senescent cell antigen on brain anion exchanger protein (AE) isoforms using HPLC and fast atom bombardment ionization mass spectrometry (FAB-MS).

Molecular recognition of senescent cells involves oxidation of a crucial membrane protein leading to generation of a neoantigen, called 'senescent cell antigen' (SCA), and binding of physiologic autoantibodies. These IgG autoantibodies trigger macrophage removal of the cell prior to its lysis at a time when anion transport has decreased but the membrane is still grossly intact. The neoantigen SCA is generated by oxidation of a major anion transport protein called band 3 or anion exchange protein. In this study, we use IgG physiologic autoantibodies from senescent red cells to isolate SCA from brain, and HPLC and fast atom bombardment ionization mass spectrometry (FAB-MS) to compare brain SCA to band 3. HPLC peptide maps of band 3 and SCA showed substantial homology, suggesting that SCA is a subset of band 3, and includes an estimated >/=45% of the band 3 molecule. FAB-MS results indicate that residues matching all three band 3 isoforms (AE1, AE2 and AE3) are detected in SCA fractions. These findings suggest that other isoforms of band 3 may undergo the same aging changes that AE1 on red blood cells undergoes to generate SCA. This provides confirmation that SCA is on non-erythroid cell types. Implications of these studies to the generation of neoantigens by oxidation and their recognition by autoantibodies to them are discussed.

Expression, purification, and inhibitory activities of mouse cytotoxic T-lymphocyte antigen-2alpha.

Cytotoxic T-lymphocyte antigen-2 (CTLA-2) is a novel cysteine proteinase inhibitor. The protein sequence is homologous to the proregion of mouse cathepsin L. Here, we report the expression, purification, and characterization of recombinant CTLA-2 (CTLA-2alpha). CTLA-2alpha was cloned into the pET16b vector and the plasmid was transformed into Escherichia coli strain BL21 (DE3) pLysS. The recombinant CTLA-2alpha was highly expressed and purified by His-Bind affinity chromatography, Factor Xa digestion, and hydrophobic chromatography. Throughout these procedures, 3mg recombinant CTLA-2alpha was obtained from 450 ml of bacterial culture medium. The purified protein exhibited inhibitory activities towards certain cysteine proteinases and was properly refolded, as indicated by circular dichroism spectroscopy. Recombinant CTLA-2alpha fully inhibited Bombyx cysteine proteinase (BCP) (overall Kd (Ki*) = 0.23 nM) and and cathepsin L (overall Kd (Ki*) = 0.38 nM). Inhibition of cathepsin H ( Ki = 86 nM) and papain ( Ki = 560 nM) was much weaker, while inhibition of cathepsin B was negligible ( Ki > 1 microM). Our results indicate that mouse CTLA-2alpha is a selective inhibitor of the cathepsin L-like cysteine proteinases.

The S100A8/A9 protein as a partner for the cytosolic factors of NADPH oxidase activation in neutrophils.

In a previous study, the S100A8/A9 protein, a Ca2+- and arachidonic acid-binding protein, abundant in neutrophil cytosol, was found to potentiate the activation of the redox component of the O2- generating oxidase in neutrophils, namely the membrane-bound flavocytochrome b, by the cytosolic phox proteins p67phox, p47phox and Rac (Doussière J., Bouzidi F. and Vignais P.V. (2001) Biochem. Biophys. Res. Commun.285, 1317-1320). This led us to check by immunoprecipitation and protein fractionation whether the cytosolic phox proteins could bind to S100A8/A9. Following incubation of a cytosolic extract from nonactivated bovine neutrophil with protein A-Sepharose bound to anti-p67phox antibodies, the recovered immunoprecipitate contained the S100 protein, p47phox and p67phox. Cytosolic protein fractionation comprised two successive chromatographic steps on hydroxyapatite and DEAE cellulose, followed by isoelectric focusing. The S100A8/A9 heterodimeric protein comigrated with the cytosolic phox proteins, and more particularly with p67phox and Rac2, whereas the isolated S100A8 protein displayed a tendancy to bind to p47phox. Using a semirecombinant cell-free system of oxidase activation consisting of recombinant p67phox, p47phox and Rac2, neutrophil membranes and arachidonic acid, we found that the S100A8/A9-dependent increase in the elicited oxidase activity corresponded to an increase in the turnover of the membrane-bound flavocytochrome b, but not to a change of affinity for NADPH or O2. In the absence of S100A8/A9, oxidase activation departed from michaelian kinetics above a critical threshold concentration of cytosolic phox proteins. Addition of S100A8/A9 to the cell-free system rendered the kinetics fully michaelian. The propensity of S100A8/A9 to bind the cytosolic phox proteins, and the effects of S100A8/A9 on the kinetics of oxidase activation, suggest that S100A8/A9 might be a scaffold protein for the cytosolic phox proteins or might help to deliver arachidonic acid to the oxidase, thus favoring the productive interaction of the cytosolic phox proteins with the membrane-bound flavocytochrome b.

Cubilin, a binding partner for galectin-3 in the murine utero-placental complex.

Galectin-3 is a lectin important in animal development and regulatory processes and is found selectively localized at the implantation site of the mouse embryo. To better understand the role of galectin-3 at the maternal-fetal interface, a binding partner was isolated and characterized. Homogenates of uteroplacental tissue were incubated with immobilized recombinant galectin-3, and specifically bound proteins were eluted using lactose. The principal protein, p400, had an M(r) of 400,000 in SDS-PAGE. Physical properties of p400 and amino acid sequences of seven tryptic peptides were similar to cubilin from rats, humans, and dogs, identifying p400 as the murine ortholog of cubilin. This was further supported by the tissue distribution observed only in yolk sac, kidney, and ileum with monospecific antiserum for p400. Cubilin occurred in yolk sac epithelium throughout pregnancy, but galectin-3 was there only during the last week. Unexpectedly, cubilin was found only in perforin-containing granules of uterine natural killer (uNK) cells, although galectin-3 occurred throughout the cell cytoplasm. In situ hybridization revealed cubilin mRNA in yolk sac epithelium but not uNK cells, implying that yolk sac-derived cubilin is endocytosed by uNK cells via galectin-3. This is consistent with cubilin being an endogenous partner of galectin-3 at the maternal-fetal interface and suggests an important role for cubilin in uNK cell function.

The murine seminiferous epithelial cycle is pre-figured in the Sertoli cells of the embryonic testis.

The seminiferous epithelial cycle and spermatogenic wave are conserved features of vertebrate spermatogenic organisation that reflect the need for the rigorous maintenance of sperm production. Although the cycle and the wave of the adult seminiferous epithelium have been well characterised, particularly in rodent species, their developmental origins are unknown. We show that the Sertoli cells of the pre-pubertal mouse, including those of the germ cell-deficient XXSxra mutant, exhibit coordinated, cyclical patterns of gene expression, presaging the situation in the adult testis, where Sertoli cell function is coupled to the spermatogenic cycle. In the case of the galectin 1 gene (Lgals1), localised differential expression in the Sertoli cells can be traced back to neonatal and embryonic stages, making this the earliest known molecular marker of functional heterogeneity in mammalian testis cords. In addition, the timing of germ cell apoptosis in normal pre-pubertal testes is linked to the temporal cycle of the Sertoli cells. These data show that the cycle and wave of the murine seminiferous epithelium originate at a much earlier stage in development than was previously known, and that their maintenance in the early postnatal cords depends exclusively on the somatic cell lineages.

Identification and characterization of nuclear CD38 in the rat spleen.

CD38 is an ectoenzyme, which can produce metabolites with intracellular Ca(2+) mobilizing properties and has multiple immunological functions. However, we have recently shown that CD38 is also localized to the nucleus of rat hepatocyte whereby its metabolite cADPR, is able to mobilize nuclear Ca(2+) stores. In this study, we further characterize the localization of nuclear CD38 in the spleen, an important immune organ. We managed to detect the presence of ADP-ribosyl cyclase activity in the nuclear fraction. With Western blotting, we managed to characterize a 42-45 kDa protein band that is typical of CD38 under reducing and non-reducing conditions. However, as a comparison, other nuclear fractions from tissues like thymus, cardiac muscle and cerebellum yielded an additional 85 kDa protein band under non-reducing conditions. Both protein bands could be blocked with a CD38 blocking peptide. Immunohistochemical studies revealed the expression of CD38 in the marginal zone and in the red pulp. In contrast, the germinal center remained largely immunonegative for CD38. This is the first report of a functionally active ADP-ribosyl cyclase/CD38 in the spleen nuclear fraction. The results here suggest that the presence of CD38 in the nuclear environment might have a corollary to functional and regulatory roles in the nucleus.

Clusterin/apolipoprotein J is a novel biomarker of cellular senescence that does not affect the proliferative capacity of human diploid fibroblasts.

Normal human fibroblasts have a limited replicative potential in culture and eventually reach a state of irreversible growth arrest, termed senescence. In a previous study aiming to identify genes that are differentially regulated during cellular senescence we have cloned clusterin/apolipoprotein J (Apo J), a 80 kDa secreted glycoprotein. In the current report we pursue our studies and show that senescence of human diploid fibroblasts is accompanied by up-regulation of both Apo J mRNA and protein levels, but with no altered biogenesis, binding partner profile or intracellular distribution of the two Apo J forms detected. To analyze the causal relationship between senescence and Apo J protein accumulation, we stably overexpressed the Apo J gene in primary as well as in SV40 T antigen-immortalized human fibroblasts and we showed no alteration of the proliferative capacity of the transduced cells. Despite previous reports on tumor-derived cell lines, overexpression of Apo J in human fibroblasts did not provide protection against apoptosis or growth arrest induced by hydrogen peroxide. Overall, our results suggest that Apo J overexpression does not induce senescence but it is rather a secondary consequence of the senescence phenotype. To our knowledge this is the first report that provides a functional analysis of human Apo J during replicative senescence.

Mammaglobin is found in breast tissue as a complex with BU101.

The mammaglobin gene has been shown to be preferentially expressed in breast tissue. Few genes match its specificity. Mammaglobin has generated much interest, and studies are ongoing to develop diagnostic tests for breast cancer based on the detection of mammaglobin. While searching the Incyte Genomics Lifeseq database for tissue-specific markers, we observed a second secretoglobin, BU101, also known as lipophilin B. We report here that mammaglobin, in breast tissue, is found as a complex with BU101. The complex was isolated from breast cancer tissue and was characterized as the biologically relevant form of mammaglobin.

Immunoaffinity isolation of CEACAM1 on hydrazide-derivatized cellulose with immobilized monoclonal anti-CEA antibody.

Carcinoembryonic cell adhesion molecule 1 (CEACAM1) is a human membrane glycoprotein belonging to the carcinoembryonic antigen (CEA) family and to the immunoglobulin superfamily. It is expressed in apical membranes of many epithelial cells in gastrointestinal and urogenital tract and also in granulocytes and lymphocytes, and its biological effect in human tissues has recently been discussed in literature. The purpose of this study was to isolate CEACAM1 glycoprotein from bile and characterize its purity and recovery which has not been described before. Affinity chromatography of CEACAM1 on hydrazide-activated cellulose with immobilized monoclonal anti-CEA F34-187 antibody is described. The immunoglobulin carbohydrate moiety was oxidized by periodate and then bound to hydrazide-activated matrix. Crude protein fraction from bile was applied on the affinity column and after extensive washing of non-bound proteins CEACAM1 was eluted with 6 M guanidine-HCl. A single immunopositive 85 kDa band was detected on Western blots with anti-CEA antibody after SDS-PAGE. We found out that CEACAM1 was not stainable with any common method of protein staining and the only non-specific method which could detect the 85 kDa band was a lectin staining.