Homo sapiens
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ABSTRACT:
PROVIDER: PRJNA277027 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:To compare gene expression profile of FCRL5+ and FCRL5- tissue-like memory B cells (CD21-/lo/CD27-/CD19+), we have employed whole genome microarray expression profiling to identify differentially regulated genes in these two B cell subgroups. B cells freshly isolated from leukapheresis of healthy donors were used in the experiment.
2016-04-26 | GSE66470 | GEO
Project description:B cell tolerance is established using deletion, anergy and receptor editing mediated by secondary recombination but it is unclear why autoreactive B cells choose a tolerance mechanism over another. We identified subgroups of patients with either rheumatoid arthritis or common variable immunodeficiency who presented defects in secondary recombination, which correlated with unusual CD21-/lo naïve B cells in their blood. CD21-/lo B cells were unable to induce calcium flux, get activated or proliferate in response to B cell receptor and/or CD40 triggering, suggesting that these B cells are anergic. Moreover, CD21-/lo B cells are often autoreactive and may express anti-nuclear antibodies. Thus, anergy can be a default tolerance mechanism mainly induced when receptor editing fails to silence developing autoreactive B cells. Experiment Overall Design: RNA was extracted from batch sorted CD19+CD21+CD10-CD27- and CD19+CD21-CD10-CD27- naïve B cells isolated from donors using the Absolutely RNA microprep kit (Stratagene). 100-200 ng of RNA was obtained per sample, and the quality of the purified RNA was assessed by the Bioanalyzer from Agilent. Using the Ovation biotin system kit from Nugen, 30-50ng of RNA was amplified and labeled to produce cDNA. Labeled cDNA was hybridized on chips containing the whole human genome (Human Genome U133 2.0 from Affymetrix). Data from CD21+ and CD21- B cell populations were compared in order to determine the gene signature of the newly described CD21- B cells.
2009-12-04 | E-GEOD-13917 | biostudies-arrayexpress
Project description:Background: In human malaria, parasites of the genus Plasmodium elicit expansion of atypical memory B cells (atMBCs), which lack the classical markers CD21 and CD27. We have identified a putative population of analogous B cells in a murine model of infection with P. chabaudi, delineated by the marker FCRL5. We performed RNA-Seq on FCRL5+ and FCRL5- B cells sorted from infected mice, so as to characterize the transcriptional profile of these cells and permit comparison to atMBCs in humans. Results: FCRL5+ B cells were found to have distinct transcriptional profiles from FCRL5- B cells, with approximately 400 genes exhibiting significant differences between the two groups. Additionally, about 25% of these differentially expressed genes were also differentially expressed in human atMBCs versus classical MBCs, as previously described by Sullivan et al (PLoS Pathogens 2015). Conclusions: FCRL5+ class-switched B cells are a transcriptionally distinct subset arising in P. chabaudi infection, with transcriptional similarities to human atMBCs that develop in chronic malaria settings.
2019-04-16 | GSE85205 | GEO
Project description:The homeostasis of circulating B cell subsets in the peripheral blood of healthy adults is well regulated, but in disease it can be severely disturbed. Thus, a subgroup of patients with common variable immunodeficiency (CVID) presents with an extraordinary expansion of an unusual B cell population characterized by the low expression of CD21. Since these circulating atypical B cells in the blood of CVID patients could not be assigned to any certain B cell differentiation stage in the periphery, they were designated as CD21low B cells. Although, CD21low B cells are polyclonal and unmutated IgM+IgD+ B cells like naive B cells in the peripheral blood, they reveal several distinct phenotypic and functional features. In order to uncover the the global programme of gene expression underlying these differences and changes in CD21low B cells we have performed microarray hybridization experiments and identified differentially expressed genes which define a distinct gene expression profile in CD21low B cells compared to naive B cells. Leucocytes were separated by Ficoll gradient from peripheral blood of healthy donors (HD) and CVID patients. CD19+CD27-CD38+CD21+ naive B cells of HD as well as naive and CD19hiCD27-CD38lowCD21low (CD21low) B cells of CVID patients were sorted using a MoFlow cell sorter. RNA was extracted from sorted ex vivo B cell subpopulations and hybridized on Affymetrix microarrays. Gene expression profiles were compared between CD21low B cells and naive B cells of CVID patients as well as HD naive B cells.
2009-07-30 | E-GEOD-17269 | biostudies-arrayexpress
Project description:Complement receptor 2–negative (CR2/CD21–) B cells have been found enriched in patients with autoimmune diseases and in common variable immunodeficiency (CVID) patients who are prone to autoimmunity. However, the physiology of CD21–/lo B cells remains poorly characterized. We found that some rheumatoid arthritis (RA) patients also display an increased frequency of CD21–/lo B cells in their blood. A majority of CD21–/lo B cells from RA and CVID patients expressed germline autoreactive antibodies, which recognized nuclear and cytoplasmic structures. In addition, these B cells were unable to induce calcium flux, become activated, or proliferate in response to B-cell receptor and/or CD40 triggering, suggesting that these autoreactive B cells may be anergic. Moreover, gene array analyses of CD21–/lo B cells revealed molecules specifically expressed in these B cells and that are likely to induce their unresponsive stage. Thus, CD21–/lo B cells contain mostly autoreactive unresponsive clones, which express a specific set of molecules that may represent new biomarkers to identify anergic B cells in humans.
2009-12-01 | GSE13917 | GEO
Project description:Circulating antibody secreting cells are present in peripheral blood of healthy individuals reflecting continued activity of the humoral immune system. Antibody secreting cells typically express CD27. We describe and characterize a small population of antibody secreting class switched CD19+CD43+ B cells that lack expression of CD27 in peripheral blood of healthy subjects. Class switched CD27-CD43+ B cells possess characteristics of conventional plasmablasts as they spontaneously secrete antibodies, are morphological similar to antibody secreting cells, show downregulation of B cell differentiation markers. In order to further characterize the cells in comparison to other B cell subtypes we performed gene expression studies. RNA was isolated from sort-purified IgA-expressing and IgG-expressing B cell subpopulations [CD27+CD43-, CD27+CD43+, CD27-CD43-, CD27-CD43+] obtained from 3 healthy adults, and microarray analysis was performed. Data from IgA-expressing B cell populations and from IgG-expressing B cell populations were normalized (separately).
2023-11-01 | E-MTAB-12406 | biostudies-arrayexpress
Project description:Rheumatoid arthritis (RA) patients may display atypical CD21-/lo B cells in their blood but the significance of this observation remains unclear. We report here that the group of RA patients with elevated frequencies of CD21-/lo B cells shows decreased ataxia-telangiectasia mutated (ATM) expression and activation in B cells compared with other RA patients and healthy donor controls. In agreement with ATM involvement in the regulation of V(D)J recombination, RA patients with defective ATM function displayed a skewed B cell receptor (BCR) Igk repertoire, which resembled that of ataxia-telangiectasia (AT) patients. This repertoire was characterized by increased Jk1 and decreased upstream Vk gene segment usage, suggesting improper secondary recombination processes and selection. In addition, altered ATM function in B cells was associated with decreased osteoprotegerin (OPG) and increased RANKL production. These changes favor bone loss and correlated with a higher prevalence of erosive disease in RA patients with impaired ATM function. Using a humanized mouse model, we also show that ATM inhibition in vivo induces an altered Igk repertoire and RANKL production by immature B cells in the bone marrow, leading to decreased bone density. We conclude that dysregulated ATM function in B cells promotes bone erosion and the emergence of circulating CD21-/lo B cells, thereby contributing to RA pathophysiology.
2019-11-23 | GSE132832 | GEO
Project description:It is unknown whether human lung T cells recirculate or belong to a distinct tissue-specific population. This issue is important for understanding their role in protection against viral infection and their contribution to pathophysiology of lung diseases such as chronic obstructive pulmonary disease. By comparing transcriptional profiles of blood and lung CD8+ T cells, we aimed to reveal specific traits of lung CD8+ T cells. A total of 12 samples was analyzed: 10 patient samples (including 1 technical replicate) and 2 reference samples (including 1 technical replicate). Per patient (in total 3 patients), 3 paired samples were analyzed. These samples were non-naive peripheral blood CD8+ T cells (CD45R0+CD3+CD8+ T cells), memory-type lung CD8+ T cells (CD45R0+CD27+CD3+CD8+ T cells) and effector-type lung CD8+ T cells (CD45R0+CD27-CD3+CD8+ T cells). The reference population consisted of a mix of naive peripheral blood CD8+ T cells from 5 healthy donors.
2011-06-20 | E-GEOD-30027 | biostudies-arrayexpress
Project description:We reported two major thymic B cell subsets (CD21+CD35+ and CD21-CD35-) with different morphology, functions and transcriptome profile. For this purpose, mRNA was extracted from cord blood CD19+ B cells and thymic B cells (CD21+CD35+ and CD21-CD35-) from neonatal donors ranged between 1 day and 4 months and sequenced using Illumina HiSeq4000.
2020-09-30 | GSE152453 | GEO
Project description:Plasma cells are not restricted to the CD27+ phenotype: characterization of CD27-CD43+ antibody secreting cells. Circulating antibody secreting cells are present in peripheral blood of healthy individuals reflecting continued activity of the humoral immune system. Antibody secreting cells typically express CD27. We describe and characterize a small population of antibody secreting class switched CD19+CD43+ B cells that lack expression of CD27 in peripheral blood of healthy subjects. Class switched CD27-CD43+ B cells possess characteristics of conventional plasmablasts as they spontaneously secrete antibodies, are morphological similar to antibody secreting cells, show downregulation of B cell differentiation markers, and have a gene expression profile related to conventional plasmablasts. Despite these similarities, we observed differences in IgA and IgG subclass distribution, expression of homing markers, replication history, frequency of somatic hypermutation and antibody response to vaccination. Their frequency is altered in immune-mediated disorders. In order to study the antibody signature we evaluated immune reactivity to 7390 human proteins by protein microarray.
2022-11-25 | GSE217855 | GEO