Project description:Dendritic cells (DC) play central roles in coordinating appropriate immune responses to pathogens. In the present study, the genes regulated by NFkB activators, RelB and cRel, in PAMP-induced bone marrow dendritic cells (BMDCs) activation was examined. Total RNA extracted from WT, relb-/-, crel-/-relb-/- bone marrow derived dendritic cells (BMDCs) were subjected to stimulation with CpG or Pam3CSK4.
Project description:NF-kappaB Activation Model includes the activation of both NFKB1:RELA and NFKB2:RELB for Canonical and Non-Canonical Pathway respectively.
The model includes the pathway model integrated with post-translational modifications of NF-kB subunits that regulate the NFKB1:RELA and NFKB2:RELB activity. The processes that are regulated by NF-kB pathway can be monitored through following readouts NFKB1:RELA Activity, NFKB2:RELB Activity, Degraded RelA, Degraded RelB, Degraded IkB, Degraded NIK, Apoptosis, Tumour, Antiviral Activity, B Cell Growth and Cell Migration. However, last 5 processes above are also influenced by other pathways too, therefore while making predictions, caution has to be exercised.
Project description:Dendritic cells (DC) play central roles in coordinating appropriate immune responses to pathogens. In the present study, the genes regulated by NFkB activators, RelB and cRel, in PAMP-induced bone marrow dendritic cells (BMDCs) activation was examined.
Project description:Malignant Hodgkin's lymphoma (HL) cells are characterized by constitutive activation of the canonical as well as the non-canonical NF-κB signaling cascades. We depleted subunit combinations corresponding to either canonical (p50/RelA) or non-canonical (p52/RelB) dimers in the HL cell line L-1236 and performed Affymetrix microarray analysis. Knockdown of p52/RelB affected the expression of a significantly higher number of genes than the knockdown of p50/RelA. The two sets of target genes presented a partial overlap, however they also revealed specific genes that are involved in distinct aspects of tumor biology. The knockdown of subunit combinations corresponding to either canonical (p50/RelA, experimental group 1) or non-canonical (p52/RelB, experimental group 2) NF-κB heterodimers were carried out in L-1236 cells. Two distinct siRNA sequences for every NF-κB subunit and two non-targeting siRNA sequences (control) were used for each experimental group. Experiments were performed in biological triplicates.
Project description:Dendritic cells (DCs) orchestrate intestinal inflammation in health and diseases. We found that human IBD was associated with heightened non-canonical NF-κB signaling in intestinal DCs. The non-canonical NF-κB pathway, which induces RelB:p52-mediated immune gene expressions, has been implicated in DC functions and that genetic inactivation of RelB:p52 in DCs alleviated experimental colitis in mice. Here, we aim to investigate the regulation of gene expression by noncanonical Nfkb2 pathway in modulating DC function.
Project description:Pro-inflammatory cytokines were shown to promote growth and survival of cancerous cells. TNF induced RelA:p50 NF-κB dimer via the canonical pathway is thought to link inflammation with cancer. Integrating biochemical and computational studies we identify that deficiency of non-canonical signal transducer p100 triggers a positive autoregulatory loop, which instead perpetuates an alternate RelB:p50 containing NF-κB activity upon TNF treatment. TNF stimulated RelB:p50 dimer is sufficient for mediating NF-κB target gene-expressions and suppressing apoptotic cellular death independent of principal NF-κB subunit RelA. We further demonstrate that activating mutations in non-canonical NF-κB module deplete multiple myeloma cells of p100, thereby, provoking autoregulatory RelB:p50 activation. Finally, autoregulatory control reinforces protracted pro-survival NF-κB response, albeit comprising of RelB:p50, upon TNF priming that protects myeloma cells with dysfunctional p100 from subsequent apoptotic insults. In sum, we present evidence for positive autoregulation mediated through the NF-κB system and its potential involvement in human neoplasm.
Project description:Mesenchymal stem cells (MSCs) are known to induce the conversion of activated T-cells into regulatory T-cells in vitro. The marker CD69 is a target of canonical NF-κB signaling and is transiently expressed upon activation; however, stable CD69 expression defines cells with immunoregulatory properties. Given its enormous therapeutic potential, we explored the molecular mechanisms underlying the induction of regulatory cells by MSCs. Peripheral blood CD3+ T-cells were activated and cultured in the presence or absence of MSCs. CD4+ cell mRNA expression was then characterized by microarray analysis. The drug BAY11-7082 and a siRNA against RELB were used to explore the differential roles of canonical and non-canonical NF-κB signaling, respectively. Flow cytometry and real-time PCR were used for analyses. Genes with immunoregulatory functions, CD69 and non-canonical NF-κB subunits (RELB and NFKB2) were all expressed at higher levels in lymphocytes co-cultured with MSCs. The frequency of CD69+ cells among lymphocytes cultured alone progressively decreased after activation. In contrast, the frequency of CD69+ cells increased significantly following activation in lymphocytes co-cultured with MSCs. Inhibition of canonical NF-κB signaling by BAY immediately following activation blocked the induction of CD69; however, inhibition of canonical NF-κB signaling on the 3rd day further induced the expression of CD69. Furthermore, late expression of CD69 was inhibited by RELB siRNA. These results indicate that the canonical NF-κB pathway controls the early expression of CD69 after activation; however, in an immunoregulatory context, late and sustained CD69 expression is promoted by the non-canonical pathway and is inhibited by canonical NF-κB signaling. In order to study the molecular basis by which Multipotent Mesenchymal Stromal/Stem Cells (MSC) exert their immune regulatory function, immunomagnetically purified CD3+ T-cells from the peripheral blood of 3 individuals were activated and cultured in the presence or absence of MSCs. Following 5 days, CD4+ and CD8+ T-cells were further immunomagnetically selected and their gene expression profiles were obtained by microarrays and compared. Paired samples from 3 individuals were used for this analysis.
Project description:Malignant Hodgkin's lymphoma (HL) cells are characterized by constitutive activation of the canonical as well as the non-canonical NF-κB signaling cascades. We depleted subunit combinations corresponding to either canonical (p50/RelA) or non-canonical (p52/RelB) dimers in the HL cell line L-1236 and performed Affymetrix microarray analysis. Knockdown of p52/RelB affected the expression of a significantly higher number of genes than the knockdown of p50/RelA. The two sets of target genes presented a partial overlap, however they also revealed specific genes that are involved in distinct aspects of tumor biology.
Project description:The malignant cells of Hodgkin's lymphoma are characterized by a constitutive activation of the canonical as well as the non-canonical NF-κB signaling cascades. We carried out genome-wide localization and expression profiling experiments in the Hodgkin lymphoma cell line L1236 for the canonical and non-canonical NF-κB pathway components p65, p50 and p52, RelB, respectively. We found that the single NF-κB subunits bind to overlapping, but distinct cistromes by using consensus motifs of high similarity. ChIP-Seq analysis of 4 NF-κB subunits with 2 biological replicates each
Project description:Mesenchymal stem cells (MSCs) are known to induce the conversion of activated T-cells into regulatory T-cells in vitro. The marker CD69 is a target of canonical NF-κB signaling and is transiently expressed upon activation; however, stable CD69 expression defines cells with immunoregulatory properties. Given its enormous therapeutic potential, we explored the molecular mechanisms underlying the induction of regulatory cells by MSCs. Peripheral blood CD3+ T-cells were activated and cultured in the presence or absence of MSCs. CD4+ cell mRNA expression was then characterized by microarray analysis. The drug BAY11-7082 and a siRNA against RELB were used to explore the differential roles of canonical and non-canonical NF-κB signaling, respectively. Flow cytometry and real-time PCR were used for analyses. Genes with immunoregulatory functions, CD69 and non-canonical NF-κB subunits (RELB and NFKB2) were all expressed at higher levels in lymphocytes co-cultured with MSCs. The frequency of CD69+ cells among lymphocytes cultured alone progressively decreased after activation. In contrast, the frequency of CD69+ cells increased significantly following activation in lymphocytes co-cultured with MSCs. Inhibition of canonical NF-κB signaling by BAY immediately following activation blocked the induction of CD69; however, inhibition of canonical NF-κB signaling on the 3rd day further induced the expression of CD69. Furthermore, late expression of CD69 was inhibited by RELB siRNA. These results indicate that the canonical NF-κB pathway controls the early expression of CD69 after activation; however, in an immunoregulatory context, late and sustained CD69 expression is promoted by the non-canonical pathway and is inhibited by canonical NF-κB signaling.