Differential Expression of Genes Associated with Toll-Like Receptor-4 (TLR4) Signal Transduction Pathway in Lipopolysaccharide (LPS)-Activated Cord Blood (CB) vs. Adult Peripheral Blood (APB) Monocyte (Mo)-Derived Dendritic Cells (DC).

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 3444-3444
Author(s):  
Hong Jiang ◽  
Mary Brigid Bradley ◽  
Carmella van de Ven ◽  
Prakash Satwani ◽  
Laxmi Baxi ◽  
...  

Abstract LPS activates immature DC via TLR4 and induces maturation of DC for initiating antigen presenting activity (Medzhitov; Nat Rev Immunol 2001). We have previously demonstrated decreased gene expression and protein production of IL-12, IL-15, IL-18 in activated CB MNC and decreased DC MLR (Lee/Cairo, Blood 1996; Qian/Cairo, Blood 1997; Wu/Cairo, Blood 100:3668 p51b 2002). Recently, we have identified differential gene expression patterns including differential immunoregulatory and chemokine genes in LPS-CB vs APB Mo by microarray (Jiang/Cairo, J. Immunol 2004). Since the myeloid lineage DC is derived from Mo, we sought to determine in LPS activated CB vs. APB DC, differential expressed genes that associate with TLR4-mediated signaling pathway. Briefly, Mo were purified from fresh CB or APB and cultured for 7 days with GM-CSF & IL-4 [immature DC (iDC)] and LPS [mature DC (mDC)]. Aliquots from iDC and mDC were analyzed for DC immunophenotype, morphology and DC allogeneic antigen activity. mRNA was isolated, reverse transcripted to cDNA, labeled & hybridized to oligonucleotides (Affymetrix, U133A). Data was analyzed by MAS 5.0 (Affymetrix) and GeneSpring 5.0 software (Silicon Genetics). Several genes were analyzed by RT-PCR (One-Step SuperScript, Invitrogen) and protein expression was analyzed by Western Blot (Bio-Rad). Inverted microscopy demonstrated DC mature morphology at day 8 and flow cytometry demonstrated decreased CD14 and increased CD83 expression in CB & APB mDC. We also demonstrated significant increase in the allogeneic stimulatory effects on CD4+ T cells in APB vs. CB mDC. The microarray analysis demonstrated a significant decreased gene expression of TLR4 [3 fold (F)] and CD14 (2.1 F) (p<0.05) in CB vs APB-DC. We further identified LPS significantly induced increased expression of TLR4 downstream signaling molecular genes such as MAPKKK, NF-kB and TANK in APB compared to CB mDC (3–8 F) (p<0.05). There were also significant amplifications of a variety of other gene categories in LPS activated APB vs CB mDC (p<0.05) including cell surface molecule CD80 (3.7F) and IL-2Ra (5.3 F), cytokine IL-23 (3.5F) & IL-12 (13 F), signal transduction STAT1 (3.4F) & IRF-7 (7.7 F), and immunoregulatory TNFSF10 (12F) & ISG20 (39F). Gene expression of NF-kB1, TRAF1 & IRF-7 by RT-PCR demonstrated an increased expression in LPS-APB vs CB mDC and were compatible with microarray. Moreover, Western analysis of IRF-7 demonstrated increased protein expression in LPS-APB vs CB mDC. In summary, we have identified decreased gene expression patterns in LPS-CB vs APB DC, especially those in the TLR4 signal transduction pathway (MAP3K, TRAF, TANK & NF-kB), and suggest these differentially expressed genes may enhance the activation of TLR4 pathway in LPS-APB vs CB DC, resulting in differential regulation of CB vs APB DC antigen presentation capacities. Furthermore, these decreased expressed genes in other molecular categories (e.g.IL-23, IFNg, IL6, CD80, STAT1, IRF-7, SOCS3) in LPS-CB vs APB DC may be partially responsible for differential innate and adaptive immune function of CB vs APB. Moreover, the differential regulated expression of genes may in part help to explain reduced incidence of severe aGVHD, delay in immune reconstitution and/or increased infectious mortality following HLA disparate UCBT.

Molecules ◽  
2018 ◽  
Vol 23 (11) ◽  
pp. 2856 ◽  
Author(s):  
Zhe Zhao ◽  
Yifan Li ◽  
Songchao Zhao ◽  
Jiawen Zhang ◽  
Hong Zhang ◽  
...  

Senescence affects the remobilization of nutrients and adaption of the plant to the environment. Combined stresses can result in premature senescence in plants which exist in the field. In this study, transcriptomic analysis was performed on mature leaves and leaves in three stages of premature senescence to understand the molecular mechanism. With progressive premature senescence, a declining chlorophyll (chl) content and an increasing malonaldehyde (MDA) content were observed, while plasmolysis and cell nucleus pyknosis occurred, mitochondria melted, thylakoid lamellae were dilated, starch grains in chloroplast decreased, and osmiophilic granules increased gradually. Moreover, in total 69 common differentially expressed genes (DEGs) in three stages of premature senescing leaves were found, which were significantly enriched in summarized Gene Ontology (GO) terms of membrane-bounded organelle, regulation of cellular component synthesis and metabolic and biosynthetic processes. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis suggested that the plant hormone signal transduction pathway was significantly enriched. The common DEGs and four senescence-related pathways, including plant hormone signal transduction, porphyrin and chlorophyll metabolism, carotenoid biosynthesis, and regulation of autophagy were selected to be discussed further. This work aimed to provide potential genes signaling and modulating premature senescence as well as the possible dynamic network of gene expression patterns for further study.


The study of phytochrome signalling has yielded a wealth of data describing both the perception of light by the receptor, and the terminal steps in phytochrome-regulated gene expression by a number of transcription factors. We are now focusing on establishing the intervening steps linking phytochrome photoactivation to gene expression, and the regulation and interactions of these signalling pathways. Recent work has utilized both a pharmacological approach in phototrophic soybean suspension cultures and microinjection techniques in tomato to establish three distinct phytochrome signal-transduction pathways: (i) a calcium-dependent pathway that regulates the expression of genes encoding the chlorophyll a/b binding protein ( CAB ) and other components of photosystem II; (ii) a cGMP-dependent pathway that regulates the expression of the gene encoding chalcone synthase ( CHS ) and the production of anthocyanin pigments; and (iii) a pathway dependent upon both calcium and cGMP that regulates the expression of genes encoding components of photosystem I and is necessary for the production of mature chloroplasts. To study the components and the regulation of phytochrome signal-transduction pathways, mutants with altered photomorphogenic responses have been isolated by a number of laboratories. However, with several possible exceptions, little real progress has been made towards the isolation of mutants in positive regulatory elements of the phytochrome signal-transduction pathway. We have characterized a novel phytochrome A (phyA)-mediated far-red light (FR) response in Arabidopsis seedlings which we are currently using to screen for specific phyA signal-transduction mutants.


2017 ◽  
Vol 35 (15_suppl) ◽  
pp. 4529-4529 ◽  
Author(s):  
Vadim S. Koshkin ◽  
Jordan Reynolds ◽  
Paul Elson ◽  
Cristina Magi-Galluzzi ◽  
Jesse McKenney ◽  
...  

4529 Background: SCBC is rare and its underlying biology poorly understood. Molecular profiling can shed light on the biology and identify treatment targets and biomarkers. Methods: A retrospective review of 63 patients (pts) with biopsy-confirmed SCBC at Cleveland Clinic (1994-2015) was performed. Percentage of small cell component (SC%) was defined by independent pathology review. DLL3 and PD-L1 protein expression were measured by IHC in 53 pts. Gene expression analysis was done in 38 primary SCBC tumor samples, 1 metastatic sample, and 5 normal bladder tissue samples (44 total) from the same cohort using HTG EdgeSeq OBP Assay with probes for 2568 genes. Analysis was performed via the RNAseq workflow (Partek Genomics Suite). Results: Among 63 identified pts, median age was 71 (39-90), 83% were men, median SC% was 100% (range 5-100%), median follow-up was 16.6 months and estimated median overall survival (OS) was 22.8 months. Unsupervised hierarchical clustering of gene expression patterns from 44 samples produced 4 distinct clusters. Pts with tumors in cluster 1 (that also included normal samples) did not have metastasis at diagnosis or distant recurrence, both of which were over-represented in the other 3 clusters. Kaplan-Meier analysis revealed a trend towards longer OS in cluster 1 patients (log rank p = 0.065). Higher gene expression of PRC1, NCAM1 (CD56) and DLL3 correlated with higher SC%, as did lower gene expression of ERBB2, PD-L1 and HPGD (p < 0.01). PD-L1 protein expression (≥1% cells) was noted in 30% of pts but did not correlate with outcome, SC%, DLL3 protein expression, or PD-L1 gene expression. DLL3 protein expression (≥1% cells) was noted in 68% of pts and DLL3 > 10% correlated with decreased OS (p = .03). Higher DLL3 protein expression correlated with DLL3 gene expression (Spearman r = 0.70, p < .01) and with SC% (r = .33, p = .01). Conclusions: This is the first study to reveal distinct gene expression patterns that define aggressive behavior, metastatic potential and outcomes in SCBC. The prognostic value of differential gene expression networks and the presence of underlying genomic and epigenetic alterations is the subject of ongoing prospective validation in a larger cohort.


1998 ◽  
Vol 851 (1 STRESS OF LIF) ◽  
pp. 129-138 ◽  
Author(s):  
DIPAK K. DAS ◽  
NILANJANA MAULIK ◽  
RICHARD M. ENGELMAN ◽  
JOHN A. ROUSOU ◽  
DAVID DEATON ◽  
...  

Platelets ◽  
2020 ◽  
Author(s):  
Sonia Águila ◽  
Ernesto Cuenca-Zamora ◽  
Constantino Martínez ◽  
Raúl Teruel-Montoya

In this chapter, we discuss different topics always using the microRNA as the guiding thread of the review. MicroRNAs, member of small noncoding RNAs family, are an important element involved in gene expression. We cover different issues such as their importance in the differentiation and maturation of megakaryocytes (megakaryopoiesis), as well as the role in platelets formation (thrombopoiesis) focusing on the described relationship between miRNA and critical myeloid lineage transcription factors such as RUNX1, chemokines receptors as CRCX4, or central hormones in platelet homeostasis like TPO, as well as its receptor (MPL) and the TPO signal transduction pathway, that is JAK/STAT. In addition to platelet biogenesis, we review the microRNA participation in platelets physiology and function. This review also introduces the use of miRNAs as biomarkers of platelet function since the detection of pathogenic situations or response to therapy using these noncoding RNAs is getting increasing interest in disease management. Finally, this chapter describes the participation of platelets in cellular interplay, since extracellular vesicles have been demonstrated to have the ability to deliver microRNAs to others cells, modulating their function through intercellular communication, redefining the extracellular vesicles from the so-called “platelet dust” to become mediators of intercellular communication.


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