Transcription profiling of human brain endothelial cells treated with TNF then incubated with platelets, P.falciparum-parasited red blood cells or normal red blood cells
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ABSTRACT: HBEC-5i (human brain endothelial cells) grown to confluence in 6-well tissue culture plates. Cocultures were either left unstimulated or incubated overnight with recombinant TNF?. HBEC were then washed in PBS and incubated with PLT (platelets), pRBC (P.falciparum-parasited red blood cells) or NRBC (normal red blood cells) according to the experimental conditions. Then HBEC were washed three times with PBS, and were harvested at 0 and 5h coculture. Each experimental condition was realized in triplicate.
Project description:Exploration of transcriptome expression in 5 control and 4 familial dysautonomia (FD) human olfactory ecto-mesenchymal stem cells (hOE-MSCs) at very early (P1 and P2) and later (P5 and P9) cell passages.
Project description:Microarray analyses allow the identification and assessment of molecular signatures in whole tissues undergoing pathological processes. To better understand cerebral malaria pathogenesis, we investigated intra-cerebral gene-expression profiles in well-defined genetically cerebral malaria-resistant (CM-R) and CM-susceptible (CM-S) mice, upon infection by Plasmodium berghei ANKA. We investigated mouse transcriptional responses prior to infection, and at early and late stages of infection by use of cDNA microarrays. Through a rigorous statistical approach with multiple testing corrections, we showed that P. berghei ANKA significantly altered brain gene expression in CM-R (BALB/c), and in CM-S (CBA/J and C57BL/6) mice, and that 327 genes discriminated between early and late infection stages, between mouse strains, and between CM-R and CM-S mice. We further identified 104, 56, 84 genes with significant differential expression between CM-R and CM-S mice on days 2, 5, and 7 respectively. The analysis of their functional annotation suggests that genes involved in metabolic energy pathways, the inflammatory response, and the neuroprotection/neurotoxicity balance play a major role in cerebral malaria pathogenesis. In particular, we evidenced the down-regulation of genes involved in oxidative phosphorylation and the Reln pathway, and the up-regulation of genes involved in the NF-kB signalling pathway in CM-S mice. In addition, our data suggest that cerebral malaria and Alzheimers disease may share some common mechanisms of pathogenesis, as illustrated by the accumulation of beta-amyloid proteins in brains of CM-S mice, but not of CM-R mice. Our results indicate that microarray analyses can provide new insights into the key events that govern malaria pathogenesis.
Project description:Gene expression patterns were investigated in well-defined genetically cerebral malaria-resistant (CM-R) and cerebral malaria-susceptible (CM-S) mouse strains. cDNA microarrays were used to search for differentially expressed genes in mouse brain. Four mouse strains, known to differ in susceptibility to cerebral malaria upon Plasmodium berghei ANKA infection, were compared: BALB/c and DBA/2 mice are CM-R, while C57BL/6 and CBA/J mice are CM-S.
Project description:We recently demonstrated that Fsh modifies in vitro the testicular transcriptome of rainbow trout at early stages of spermatogenesis. Some of the regulated genes were found related to pathways highly relevant for the testicular functions i.e. spermatogenesis and steroidogenesis. Unlike in mammals, in fish both gonadotropins are able to efficiently stimulate the steroidogenesis, likely through a direct interaction with their cognate receptors present on the Leydig cells. In this context, we wondered whether the effects of Fsh on the tubular compartment were mediated through the production of steroids. To address this issue we performed in vitro incubations of testis explants in the presence of Fsh alone or in combination with an inhibitor of the steroidogenesis, the trilostane. Trilostane significantly reduced or suppressed the response to Fsh of many genes showing that important aspects of the Fsh action on fish testis is indirect and requires the production of steroids. Interestingly, most of the genes regulated in response to Fsh through the steroid mediation were similarly regulated by Lh and many were also found regulated by androgen treatment. On the other hand, for many other genes the response to Fsh was not affected in the presence of trilostane. A majority of those genes were also preferentially regulated by Fsh, as compared to Lh, suggesting that specific regulatory effects of Fsh were independent of steroid production. Finally antagonistic effects between Fsh and steroids were found, in particular for genes encoding clue factors of steroidogenesis or for genes of the Igf system that tended to be inhibited by androgens. Testes were collected from all-male population rainbow trout at early stages of spermatogenesis.Testes were chopped in small pieces, in sterile conditions and then pooled and mixed. Testis fragments were randomly distributed (60-80 mg per well) on Nunc polycarbonate membrane inserts in 24-well plates filled with 300 µL of modified L15 culture medium supplemented with 2% Ultroser SF. Incubation were performed in six replicates for 96 hours, at 12°C, in the absence or presence of purified trout Fsh alone (500 ng/mL) or in combination with 10 µg/mL trilostane, an inhibitor of 3 beta-hydroxysteroid dehydrogenase. A pre-incubation with trilostane was done for 1 hour before adding Fsh.
Project description:In all vertebrates, the dual function of testis (production of sexual steroids and production of gametes) is mainly regulated by two gonadotropic pituitary hormones, FSH and LH. However, in fish the biological activities of the two hormones are not still clearly delineated and moreover, their molecular mechanisms are yet poorly understood. In this study we investigated the effects of FSH and LH on testicular gene expression, in the rainbow trout, at two developmental stages I-II and III (I: spermatogonia only, II: active spermatogonia proliferation, III: meiosis onset with the appearance of spermatocytes and round spermatids). Testes were collected from all-male population rainbow trout and incubated in six replicates for 96 hours, at 12°C, in the absence or presence of purified salmonid gonadotropins, FSH and LH (500 ng/mL).
Project description:Sexual steroids play an important role in gonad maturation in all vertebrates. However, the molecular mechanisms regulating of spermatogenesis in seasonal breeding species are yet poorly understood. In this study we investigated the effects of testosterone and 11-ketotestosterone (11KT) - a teleost fish specific androgen - on testicular gene expression at the onset of puberty in the rainbow trout, Oncorhynchus mykiss. Rainbow trout 13 months old were used. Immature males (spermatogonia only, stage I-II) were submitted to androgen supplementation by hormone implants for 7 or 14 days. This included : - untreated animal controls (N=14) - animals subjected to testosterone supplementation (0.1mg) for 7 days (N=5) - animals subjected to testosterone supplementation (0.2mg) for 7 days (N=4) - animals subjected to testosterone supplementation (0.2mg) for 14 days (N=5) - animals subjected to 11-ketotestosterone supplementation (0.25mg) for 7 days (N=7). Individual testes were recovered for microarray experiments and histological analyses. Circulating levels of corresponding androgens were also determined.
Project description:Trout spermatogenesis proceeds seasonally in a way that all morphological and cellular events tend to be synchronized. We thus used gonads at key stages of the male reproductive cycle together with isolated germ cell populations to study the changes in gene expression underlying testis development. Statistical analysis followed by clustering of expression profiles allowed the discrimination of sequential events of gene activation or repression during testis development and/or throughout the germline. 38 samples covering 6 developmental stages (as defined in Gomez et al. 1998 Biol. Reprod. 58, 483-491) and 3 isolated germ cell populations were analysed. This included: - Testes at early stages containing slowly-dividing type A spermatogonia (Stage_I, n=5) or growing numbers of actively-dividing type B spermatogonia (Stages_IIa, n= 4; Stage_IIb, n= 4) - Maturing testes containing in addition large numbers of meiotic spermatocytes (Stage_IIIb, n=3) and post-meiotic spermatids (Stage_V, n=4) - Spawning testes containing essentially mature spermatozoa (Stage_VIII, n=3) - Fractions of isolated germ cells enriched in spermatogonia (Spermatogonia, N=6), spermatocytes (Spermatocyte, N=6) and spermatids (Spermatid, N=3).
Project description:The antenno-maxilary complex (AMC) forms the chemosensory system of the Drosophila larva and is involved in gustatory and olfactory perception. We have previously shown that a mutant allele of the homeodomain transcription factor Prospero (prosVoila1, V1), presents several developmental defects including abnormal growth and altered taste responses. In addition, many neural tracts connecting the AMC to the central nervous system (CNS) were affected. Our earlier reports on larval AMC did not argue in favour of a role of pros in cell fate decision, but strongly suggested that pros could be involved in the control of other aspect of neuronal development. In order to identify these functions, we used microarray analysis of larval AMC and CNS tissue isolated from the wild type, and three other previously characterised prospero alleles, including the V1 mutant, considered as a null allele for the AMC. A total of 17 samples were first analysed with hierarchical clustering. To determine those genes affected by loss of pros function, we calculated a discriminating score reflecting the differential expression between V1 mutant and other pros alleles. We identified a total of 64 genes in the AMC. Additional manual annotation using all the computed information on the attributed role of these genes in the Drosophila larvae nervous system, enabled us to identify a first functional category of potential Prospero target genes known to be involved in neurite outgrowth, synaptic transmission and more specifically in neuronal connectivity remodelling. The second category of genes found to be differentially expressed between the null mutant AMC and the other alleles concerned the development of the sensory organs and more particularly the larval olfactory system. Surprisingly, a third category emerged from our analyses and suggests an association of pros with the genes that regulate autophagy, growth and insulin pathways. Interestingly, EGFR and Notch pathways were represented in all of these three functional categories. We now propose that Pros could perform all of these different functions through the modulation of these two antagonistic and synergic pathways. The current data contribute to the clarification of the Prospero function in the larval AMC and show that pros regulates different function in larvae as compared to those controlled by this gene in embryos. In the future, the possible mechanism by which Pros could achieve its function in the AMC and the possible involvement of EGFR and Notch pathway will be explored in detail Gene expression was measured in two different tissues (Brain and AMC) of prospero mutants flies (V1, V13, V14, V24). 3 biological replicates were performed for V1, V13 and V24 AMC and V14 Brain; 2 biological replicates for V14 AMC and V13 Brain.
Project description:Cerebral malaria is the most deadly manifestation of infection with Plasmodium falciparum. The pathology of cerebral malaria is characterised by the accumulation of infected erythrocytes in the microvasculature of the brain, due to parasite adhesins on the surface of infected erythrocytes binding to human receptors on microvascular endothelial cells. The parasite and host molecules involved in this interaction are unknown. We used the Human Brain Endothelial Cell line HBEC-5i to identify the malaria parasite ligands responsible for binding to human brain endothelial cells. Three P. falciparum strains (HB3, 3D7 and IT/FCR3) were selected for binding to HBEC5i and the whole transcriptome of selected and unselected parasites was analysed using a variant surface antigen-supplemented microarray chip. After selection, the only highly upregulated genes were a subset of group A-like var genes (HB3var3, 3D7_PFD0020c, ITvar7 and ITvar19), that showed 11 to >100-fold higher transcription levels in selected parasites. These genes are highly diverse in sequence, but do however show strong similarities in PfEMP1 architecture. Antibodies raised to the HB3var3 variant recognized the surface of infected erythrocytes and abolished the binding of infected erythrocytes to brain endothelial cells. The subset of Group A PfEMP1 variants identified here provides a new target for interventions to treat or prevent cerebral malaria. Unselected Plasmodium falciparum parasites (Uns) only poorly cytoadhere to human brain endothelial cells (HBEC-5i). Plasmodium falciparum HB3, 3D7 and IT/FCR3 strains were selected for binding to HBEC-5i (HB3-HBEC1, HB3-HBEC2, HB3-HBEC-TNF, 3D7-HBEC and IT-HBEC). HBEC-selected and unselected cultures were tightly synchronised before a timecourse experiment was performed. 6 samples, named time points 1 to 6, were taken every 8 hours. 12μg of RNA from the unselected parasites (HB3-Uns, 3D7-Uns or IT-Uns) at each of the 6 time points was combined together to form the reference pool. The pool and 12μg of each individual time point sample from both selected and unselectedparasites were then used for cDNA synthesis. For HB3-HBEC1 (pilot experiment), each HB3-HBEC1 time point (pilot experiment) was hybridised directly with HB3-Uns1 time points. For microarray hybridizations, each cDNA sample was coupled to Cy5 (red dye) while Cy3 (green dye) was added to the pool. Cy5-labelled time point samples were mixed with the same amount of Cy3-labelled pool sample. The solution was loaded on a microarray slide and hybridized for 14–16 h.
Project description:Hep3B cells were treated with the chemotherapeutic drug bleomycin. RNA was isolated after 18 h, 24 h and 36 h. The status of the gene expression was examined in response to treatment with bleomycin,