scholarly journals Integrated pathogen load and dual transcriptome analysis of systemic host-pathogen interactions in severe malaria

2017 ◽  
Author(s):  
Hyun Jae Lee ◽  
Michael Walther ◽  
Athina Georgiadou ◽  
Davis Nwakanma ◽  
Lindsay B. Stewart ◽  
...  

AbstractThe pathogenesis of severe Plasmodium falciparum malaria is incompletely understood. Since the pathogenic stage of the parasite is restricted to blood, dual RNA-sequencing of host and parasite transcripts in blood can reveal their interactions at a systemic scale. Here we identify human and parasite gene expression associated with severe disease features in Gambian children. Differences in parasite load explained up to 99% of differential expression of human genes but only a third of the differential expression of parasite genes. Co-expression analyses showed a remarkable co-regulation of host and parasite genes controlling translation, and host granulopoiesis genes uniquely co-regulated and differentially expressed in severe malaria. Our results indicate that high parasite load is the proximal stimulus for severe P. falciparum malaria, that there is an unappreciated role for many parasite genes in determining virulence, and hint at a molecular arms-race between host and parasite to synthesise protein products.

Genome ◽  
2011 ◽  
Vol 54 (2) ◽  
pp. 120-127 ◽  
Author(s):  
Daniel Onofre Vidal ◽  
Jorge Estefano S. de Souza ◽  
Lilian Campos Pires ◽  
Cibele Masotti ◽  
Anna Christina Matos Salim ◽  
...  

Recent reports have demonstrated that a significant proportion of human genes display allelic differential expression (ADE). ADE is associated with phenotypic variability and may contribute to complex genetic diseases. Here, we present a computational analysis of ADE using allele-specific serial analysis of gene expression (SAGE) tags representing 1295 human genes. We identified 472 genes for which unequal representation (>3-fold) of allele-specific SAGE tags was observed in at least one SAGE library, suggesting the occurrence of ADE. For 235 out of these 472 genes, the difference in the expression level between both allele-specific SAGE tags was statistically significant (p < 0.05). Eleven candidate genes were then subjected to experimental validation and ADE was confirmed for 8 out of these 11 genes. Our results suggest that at least 25% of the human genes display ADE and that allele-specific SAGE tags can be efficiently used for the identification of such genes.


2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Kenji Inoue ◽  
Tatsuhiko Kodama ◽  
Hiroyuki Daida

Numerous studies have recently examined the role of pentraxin 3 (PTX3) in clinical situations. The pentraxin family includes C-reactive protein (CRP); however, unlike CRP, PTX3 is expressed predominantly in atherosclerotic lesions that involve macrophages, neutrophils, dendritic cells, or smooth muscle cells. Interestingly, PTX3 gene expression in human endothelial cells is suppressed to a greater extent by pitavastatin than the expression of 6,000 other human genes that have been examined, suggesting that PTX3 may be a novel biomarker for inflammatory cardiovascular disease. The expression and involvement of PTX3 in cardiovascular diseases are discussed in this paper, along with the characteristics of PTX3 that make it a suitable biomarker; namely, that the physiological concentration is known and it is independent of other risk factors. The results discussed in this paper suggest that further investigations into the potential novel use of PTX3 as a biomarker for inflammatory cardiovascular disease should be undertaken.


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Salvatore Sciacchitano ◽  
Andrea Sacconi ◽  
Claudia De Vitis ◽  
Giovanni Blandino ◽  
Giulia Piaggio ◽  
...  

AbstractRas gene family members play a relevant role in cancer, especially when they are mutated. However, they may play additional roles in other conditions beside cancer. We performed gene expression analysis using the NanoString PanCancer IO 360 panel in the peripheral blood mononuclear cell (PBMC) of six COVID-19 patients and we found that H-Ras gene was significantly upregulated, while both K-Ras and N-Ras genes were downregulated. In particular, H-Ras gene upregulation was more evident in COVID-19 patients with a more severe disease. We compared our results with those obtained by analyzing two different and independent datasets, including a total of 53 COVID-19 patients, in which the gene expression analysis was performed using the Immunology_V2 panel. Comparative analysis of the H-Ras gene expression in these patients confirmed our preliminary results. In both of them, in fact, we were able to confirm the upregulation of the expression of the H-Ras gene. The exact role of this specific upregulation of the H-Ras gene in response to SARS-CoV-2 infection and its possible role in cancer still remains to be elucidated. In conclusion, H-Ras gene participates to the host immune response to SARS-CoV-2 virus infection, especially in patients affected by the most severe form of the COVID-19.


2021 ◽  
Vol 15 (1) ◽  
Author(s):  
Weitong Cui ◽  
Huaru Xue ◽  
Lei Wei ◽  
Jinghua Jin ◽  
Xuewen Tian ◽  
...  

Abstract Background RNA sequencing (RNA-Seq) has been widely applied in oncology for monitoring transcriptome changes. However, the emerging problem that high variation of gene expression levels caused by tumor heterogeneity may affect the reproducibility of differential expression (DE) results has rarely been studied. Here, we investigated the reproducibility of DE results for any given number of biological replicates between 3 and 24 and explored why a great many differentially expressed genes (DEGs) were not reproducible. Results Our findings demonstrate that poor reproducibility of DE results exists not only for small sample sizes, but also for relatively large sample sizes. Quite a few of the DEGs detected are specific to the samples in use, rather than genuinely differentially expressed under different conditions. Poor reproducibility of DE results is mainly caused by high variation of gene expression levels for the same gene in different samples. Even though biological variation may account for much of the high variation of gene expression levels, the effect of outlier count data also needs to be treated seriously, as outlier data severely interfere with DE analysis. Conclusions High heterogeneity exists not only in tumor tissue samples of each cancer type studied, but also in normal samples. High heterogeneity leads to poor reproducibility of DEGs, undermining generalization of differential expression results. Therefore, it is necessary to use large sample sizes (at least 10 if possible) in RNA-Seq experimental designs to reduce the impact of biological variability and DE results should be interpreted cautiously unless soundly validated.


2017 ◽  
Vol 117 (04) ◽  
pp. 758-768 ◽  
Author(s):  
Sebastian Armasu ◽  
Bryan McCauley ◽  
Iftikhar Kullo ◽  
Hugues Sicotte ◽  
Jyotishman Pathak ◽  
...  

SummaryTo identify novel single nucleotide polymorphisms (SNPs) associated with venous thromboembolism (VTE) in African-Americans (AAs), we performed a genome-wide association study (GWAS) of VTE in AAs using the Electronic Medical Records and Genomics (eMERGE) Network, comprised of seven sites each with DNA biobanks (total ~39,200 unique DNA samples) with genome-wide SNP data (imputed to 1000 Genomes Project cosmopolitan reference panel) and linked to electronic health records (EHRs). Using a validated EHR-driven phenotype extraction algorithm, we identified VTE cases and controls and tested for an association between each SNP and VTE using unconditional logistic regression, adjusted for age, sex, stroke, site-platform combination and sickle cell risk genotype. Among 393 AA VTE cases and 4,941 AA controls, three intragenic SNPs reached genome-wide significance: LEMD3 rs138916004 (OR=3.2; p=1.3E-08), LY86 rs3804476 (OR=1.8; p=2E-08) and LOC100130298 rs142143628 (OR=4.5; p=4.4E-08); all three SNPs validated using internal cross-validation, parametric bootstrap and meta-analysis methods. LEMD3 rs138916004 and LOC100130298 rs142143628 are only present in Africans (1000G data). LEMD3 showed a significant differential expression in both NCBI Gene Expression Omnibus (GEO) and the Mayo Clinic gene expression data, LOC100130298 showed a significant differential expression only in the GEO expression data, and LY86 showed a significant differential expression only in the Mayo expression data. LEMD3 encodes for an antagonist of TGF-β-induced cell proliferation arrest. LY86 encodes for MD-1 which down-regulates the pro-inflammatory response to lipopolysaccharide; LY86 variation was previously associated with VTE in white women; LOC100130298 is a non-coding RNA gene with unknown regulatory activity in gene expression and epigenetics.Supplementary Material to this article is available online at www.thrombosis-online.com.


2006 ◽  
Vol 26 (2) ◽  
pp. 109-115 ◽  
Author(s):  
Kenneth C. Bilchick ◽  
Sudip K. Saha ◽  
Ed Mikolajczyk ◽  
Leslie Cope ◽  
Will J. Ferguson ◽  
...  

Routine clinical right ventricular pacing generates left ventricular dyssynchrony manifested by early septal shortening followed by late lateral contraction, which, in turn, reciprocally stretches the septum. Dyssynchrony is disadvantageous to cardiac mechanoenergetics and worsens clinical prognosis, yet little is known about its molecular consequences. Here, we report the influence of cardiac dyssynchrony on regional cardiac gene expression in mice. Mice were implanted with a custom-designed miniature cardiac pacemaker and subjected to 1-wk overdrive right ventricular free wall pacing (720 beats/min, baseline heart rate 520–620 beats/min) to generate dyssynchrony (pacemaker: 3-V lithium battery, rate programmable, 1.5 g, bipolar lead). Electrical capture was confirmed by pulsed-wave Doppler and dyssynchrony by echocardiography. Gene expression from the left ventricular septal and lateral wall myocardium was assessed by microarray (dual-dye method, Agilent) using oligonucleotide probes and dye swap. Identical analysis was applied to four synchronously contracting controls. Of the 22,000 genes surveyed, only 18 genes displayed significant ( P < 0.01) differential expression between septal/lateral walls >1.5 times that in synchronous controls. Gene changes were confirmed by quantitative PCR with excellent correlations. Most of the genes ( n = 16) showed greater septal expression. Of particular interest were seven genes coding proteins involved with stretch responses, matrix remodeling, stem cell differentiation to myocyte lineage, and Purkinje fiber differentiation. One week of iatrogenic cardiac dyssynchrony triggered regional differential expression in relatively few select genes. Such analysis using a murine implantable pacemaker should facilitate molecular studies of cardiac dyssynchrony and help elucidate novel mechanisms by which stress/stretch stimuli due to dyssynchrony impact the normal and failing heart.


1985 ◽  
Vol 59 (1) ◽  
pp. 23-28 ◽  
Author(s):  
Ayub Kassuku ◽  
Peter Nansen ◽  
Niels Ø. Christensen

AbstractThe comparative efficiency of the percutaneous and per-oral routes of infection was studied in goats experimentally infected withSchistosoma bovis.The heaviest infection was obtained by the percutaneous route, but a relatively high parasite load was also achieved by the per-oral route, i.e., where goats were allowed to drink a cercarial suspension, volume of 0·9 to 1·7 litre per animal. Studies using radio-isotopically labelled cercariae were designed to clarify the cercarial penetration sites following uptake by drinking. Radioactivity could be demonstrated in the outer lips, buccal cavity, oesophagus and the reticulum, omasum and rumen. Highest counts were recorded in outer lips, reticulum and rumen constituting 41·2, 22·1 and 20·6%, respectively, of total radioactivity recovered. It is concluded that the per-oral infection route may play a larger role than hitherto anticipated in infection of ruminants, and possibly also in other mammals, with schistosomes. The epidemiological implications of the present findings are discussed.


2002 ◽  
Vol 76 (22) ◽  
pp. 11688-11703 ◽  
Author(s):  
Lucia Labrada ◽  
Xiao Huan Liang ◽  
Wei Zheng ◽  
Christine Johnston ◽  
Beth Levine

ABSTRACT Several different mammalian neurotropic viruses produce an age-dependent encephalitis characterized by more severe disease in younger hosts. To elucidate potential factors that contribute to age-dependent resistance to lethal viral encephalitis, we compared central nervous system (CNS) gene expression in neonatal and weanling mice that were either mock infected or infected intracerebrally with a recombinant strain, dsTE12Q, of the prototype alphavirus Sindbis virus. In 1-day-old mice, infection with dsTE12Q resulted in rapidly fatal disease associated with high CNS viral titers and extensive CNS apoptosis, whereas in 4-week-old mice, dsTE12Q infection resulted in asymptomatic infection with lower CNS virus titers and undetectable CNS apoptosis. GeneChip expression comparisons of mock-infected neonatal and weanling mouse brains revealed developmental regulation of the mRNA expression of numerous genes, including some apoptosis regulatory genes, such as the proapoptotic molecules caspase-3 and TRAF4, which are downregulated during development, and the neuroprotective chemokine, fractalkine, which is upregulated during postnatal development. In parallel with increased neurovirulence and increased viral replication, Sindbis virus infection in 1-day-old mice resulted in both a greater number of host inflammatory genes with altered expression and greater changes in levels of host inflammatory gene expression than infection in 4-week-old mice. Only one inflammatory response gene, an expressed sequence tag similar to human ISG12, increased by a greater magnitude in infected 4-week-old mouse brains than in infected 1-day-old mouse brains. Furthermore, we found that enforced neuronal ISG12 expression results in a significant delay in Sindbis virus-induced death in neonatal mice. Together, our data identify genes that are developmentally regulated in the CNS and genes that are differentially regulated in the brains of different aged mice in response to Sindbis virus infection.


2021 ◽  
Author(s):  
Sarah E. Fritz ◽  
Soumya Ranganathan ◽  
J. Robert Hogg

AbstractThe nonsense-mediated mRNA decay (NMD) pathway monitors translation termination to degrade transcripts with premature stop codons and regulate thousands of human genes. Due to the major role of NMD in RNA quality control and gene expression regulation, it is important to understand how the pathway responds to changing cellular conditions. Here we show that an alternative mammalian-specific isoform of the core NMD factor UPF1, termed UPF1LL, enables condition-dependent remodeling of NMD specificity. UPF1LL associates more stably with potential NMD target mRNAs than the major UPF1SL isoform, expanding the scope of NMD to include many transcripts normally immune to the pathway. Unexpectedly, the enhanced persistence of UPF1LL on mRNAs supports induction of NMD in response to rare translation termination events. Thus, while canonical NMD is abolished by translational repression, UPF1LL activity is enhanced, providing a mechanism to rapidly rewire NMD specificity in response to cellular stress.


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