Ontology highlight
ABSTRACT:
PROVIDER: PRJNA832136 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Functional tuning of mature T cells based on their degree of self-reactivity is established during positive selection in the thymus, although how positive selection differs for thymocytes with relatively low versus high self-reactivity is unclear. In addition, preselection thymocytes are highly sensitive to low-affinity ligands, but the mechanism underlying their enhanced TCR sensitivity is not fully understood. Here we show that thymocytes with low self-reactivity experience briefer TCR signals and complete positive selection more slowly than those with high self-reactivity. Additionally, we provide evidence that cells with low self-reactivity retain a preselection gene expression signature as they mature, including genes previously implicated in modulating TCR sensitivity and a novel group of ion channel genes. Our results imply that thymocytes with low self-reactivity down-regulate TCR sensitivity more slowly during positive selection, and suggest that modulation of membrane ion channel function may play a role in regulating TCR tuning throughout development.
2021-01-16 | GSE164896 | GEO
Project description:The T cell receptor (TCR) determines the specificity and affinity for both foreign and self-peptides presented by MHC. It is established that self-pMHC reactivity impacts T cell function, but it has been challenging to identify TCR sequence features that predict T cell fate. To discern patterns distinguishing TCRs from naïve CD4+ T cells with low versus high self-pMHC reactivity, we used data from 42 mice to train a machine learning (ML) algorithm that predicts self-reactivity directly from TCRβ sequences. This approach revealed that n-nucleotide additions and acidic amino acids weaken selfreactivity. We tested our ML predictions of TCRβ sequence self-reactivity using retrogenic mice. Extrapolating our analyses to independent datasets, we found high predicted self-reactivity for regulatory CD4+ T cells and low predicted self-reactivity for T cells responding to chronic infection. Our analyses suggest a potential trade-off between repertoire diversity and self-reactivity intrinsic to the architecture of a TCR repertoire.
2023-01-09 | GSE221703 | GEO
Project description:The pathogenesis of Chlamydophila (C.) psittaci negative ocular adnexal extranodal marginal zone lymphomas (OAEMZLs) is poorly understood. OAEMZLs are monoclonal tumors expressing a biased repertoire of mutated surface immunoglobulins. Antigenic activation of the B cell receptor (BCR) may play a role in the pathogenesis of these lymphomas. We have analyzed the reactivity of recombinant OAEMZL immunoglobulins. OAEMZL antibodies reacted with self-human antigens, as demonstrated by enzyme-linked immunosorbent assays, HEp-2 immunofluorescence and human protein microarrays. All the analyzed recombinant antibodies (rAbs) exhibited polyreactivity by comprehensive protein array antibody reactivity and some rAbs also demonstrated rheumatoid factor activity. The identity of several reactive antigens was confirmed by microcapillary reverse-phase HPLC nano-electrospray tandem mass spectrometry. The tested rAbs frequently reacted with shared intracellular and extracellular self-antigens (e.g. galectin-3). Furthermore, these self-antigens induced BCR signaling in B cells expressing cognate surface immunoglobulins derived from OAEMZLs. These findings suggest that interactions between self-antigens and cognate OAEMZL tumor-derived BCRs are functional, inducing intracellular signaling. Overall our findings suggest that self-antigen-induced BCR stimulation may be implicated in the pathogenesis of C. psittaci negative OAEMZLs. Antibody Specificity Profiling with four OAEMZL rAbs (Ab4438, Ab4726, Ab5334, and Ab11274) performed on ProtoArray Human Protein Microarrays
2015-01-30 | E-GEOD-65443 | biostudies-arrayexpress
Project description:Human cytomegalovirus infection (CMV) can stimulate robust human leukocyte antigen (HLA)-E restricted CD8 T cell responses. These T cells recognize a peptide from UL40, which differs by as little as a single methyl group from self-peptides that also bind HLA-E, challenging their capacity to avoid self-reactivity. We showed in one donor 2 distinct populations of UL40/HLA-E T cells, with vastly different T cell receptor (TCR) affinities for the UL40/HLA-E complex. However, paradoxically, lower cytokine responses were observed from UL40/HLA-E T cells bearing TCRs with high affinity for HLA-E. To identify why these T cells bearing high affinity T cell receptors were less responsive to antigens, we performed single cell RNAseq analysis. These 2 distinct populations of T cells were single-cell sorted into 96-well plates prior to single cell RNA-seq analysis.
2021-05-21 | E-MTAB-10305 | biostudies-arrayexpress
Project description:The pathogenesis of Chlamydophila (C.) psittaci negative ocular adnexal extranodal marginal zone lymphomas (OAEMZLs) is poorly understood. OAEMZLs are monoclonal tumors expressing a biased repertoire of mutated surface immunoglobulins. Antigenic activation of the B cell receptor (BCR) may play a role in the pathogenesis of these lymphomas. We have analyzed the reactivity of recombinant OAEMZL immunoglobulins. OAEMZL antibodies reacted with self-human antigens, as demonstrated by enzyme-linked immunosorbent assays, HEp-2 immunofluorescence and human protein microarrays. All the analyzed recombinant antibodies (rAbs) exhibited polyreactivity by comprehensive protein array antibody reactivity and some rAbs also demonstrated rheumatoid factor activity. The identity of several reactive antigens was confirmed by microcapillary reverse-phase HPLC nano-electrospray tandem mass spectrometry. The tested rAbs frequently reacted with shared intracellular and extracellular self-antigens (e.g. galectin-3). Furthermore, these self-antigens induced BCR signaling in B cells expressing cognate surface immunoglobulins derived from OAEMZLs. These findings suggest that interactions between self-antigens and cognate OAEMZL tumor-derived BCRs are functional, inducing intracellular signaling. Overall our findings suggest that self-antigen-induced BCR stimulation may be implicated in the pathogenesis of C. psittaci negative OAEMZLs.
2015-01-30 | GSE65443 | GEO
Project description:This model of the immune system response to antigen presentation is based on the publication:
Eduardo D.Sontag (2017) 'A Dynamic Model of Immune Responses to Antigen Presentation Predicts Different Regions of Tumor or Pathogen Elimination', Cell Systems, 4(2)
DOI: 10.1016/j.cels.2016.12.003
Comment:
This model is based on the "toy model" as described by Equations 1A-1C from the manuscript and the system represented by Equation 2, which exhibits a type of incoherent feedforward loop (IFFL).
Abstract:
The immune system must discriminate between agents of disease and an organism’s healthy cells. While the identification of an antigen as self/non-self is critically important, the dynamic features of antigen presentation may also determine the immune system’s response. Here, we use a simple mathematical model of immune activation to explore the idea of antigen discrimination through dynamics. We propose that antigen presentation is coupled to two nodes, one regulatory and one effecting the immune response, through an incoherent feedforward loop and repressive feedback. This circuit would allow the immune system to effectively estimate the increase of antigens with respect to time, a key determinant of immune reactivity in vivo. Our model makes the prediction that tumors growing at specific rates evade the immune system despite the continuous presence of antigens indicating disease, a phenomenon closely related to clinically observed “two-zone tolerance.” Finally, we discuss a plausible biological instantiation of our circuit using combinations of regulatory and effector T cells.
2021-08-16 | BIOMD0000001030 | BioModels
Project description:Naive T cells experience accumulation of TCR signaling in response to self-antigens in the steady state. However, how these signals influence the responsiveness of naive CD8+ T cells to subsequent agonist TCR stimulation remains incompletely understood. We investigated how naive CD8+ T cells that experienced relatively low or high levels of TCR signaling in response to self-antigens respond to stimulation with foreign antigens. A transcriptional reporter of Nr4a1 (Nur77-GFP) revealed substantial heterogeneity of the amount of TCR signaling naive CD8+ T cells accumulate in the steady state. To further understand the impact of differential TCR signaling on CD8 T cells we performed RNA-seq on naive Nur77-GFPhi and lo populations.
2023-03-02 | GSE223457 | GEO
Project description:In this study, we show that in addition to regulating DP thymocytes survival, RORgT also controls genes that regulate thymocyte migration, proliferation, and T cell receptor (TCR) selection. Strikingly, pharmacological inhibition of RORg skews TCR gene rearrangement, limits T cell repertoire diversity, and inhibits development of autoimmune encephalomyelitis. Thus, targeting RORgT not only inhibits Th17 cell development and function but also fundamentally alters thymic-emigrant recognition of self and foreign antigens.
2016-10-20 | GSE88916 | GEO
Project description:The presented data corresponds to the analysis of two discrete subsets of human CD8+ naive T cells, defined by positive and negative expression of the chemokine receptor CXCR3 (TNR3-, TNR3+). In this study we demonstrated that these subsets have different potential to generate fully-differentiated effector T cells following antigen-specific stimulation. The performed systematic immune repertoire analysis (T cell receptor beta chain (TRB)) of the sorted cell subsets revealed diverse physico-chemical properties of TRB CDR3 sequences suggesting enhanced TCR self-reactivity in human TNR3+ cells. In total, we analyzed 74 samples (from 11 patients, 3 replicates of each cell subset (excluding one missing replicate) and additionally for 3 patients CD8+ memory T cells in 3 replicates). We used the Human TCR Profiling Kit (MiLaboratory LLC) for sequencing libraries preparation and Illumina NextSeq 550 sequencing (150+150bp) followed by the demultiplexing procedure using MIGEC software (https://github.com/mikessh/migec).
2019-10-17 | E-MTAB-7638 | biostudies-arrayexpress
Project description:Anti-CD4 monoclonal antibody, a prominent immunomodulatory agent, elicits robust anti-tumor immunity in various cancers by increasing tumor-infiltrating lymphocytes and promoting CD8+ T cell reactivity against tumor cell-derived antigens. We conducted TCR repertoire analysis of anti-CD4-exposed endogenous CD8+ T cells to investigate the expansion pattern of the cell population.
2021-08-03 | GSE181280 | GEO