Similar Datasets
Project description:Compared with naïve B cells, the B cell receptor (BCR) signal in germinal center (GC) B cells is attenuated; however, the significance of this signaling attenuation has not been well defined. Here, to investigate the role of attenuation of BCR signaling, we employed a Csk mutant mouse model in which Csk-deficiency in GC B cells resulted in augmentation of net BCR signaling with no apparent effect on antigen presentation. We found that Csk is required for GC maintenance and efficient antibody affinity maturation. Mechanistically, ROS-induced apoptosis was exacerbated concomitantly with mitochondrial dysfunction in Csk-deficient GC B cells. Hence, our data suggest that attenuation of the BCR signal restrains hyper-ROS production, thereby protecting GC B cells from apoptosis and contributing to efficient affinity maturation.
2024-05-06 | GSE244802 | GEO
Project description:To address the molecular mechanisms underlying c-Src-mediated tumor progression, we previously developed a model system using Csk-deficient fibroblasts that can be transformed by wild-type c-Src. In this study, we applied this system for the analysis of the potential contribution of miRNA to c-Src-mediated transformation. Pair-wise significance analysis of the microarray indicated that seven miR genes were significantly upregulated and six miRNA genes were downregulated in c-Src-transformed cells with a P value below 0.01 and with a fold change over 2.0. Csk-/- mouse embryonic fibroblasts (Csk-/- MEFs) were transfected with empty vector, c-Src, Csk/c-Src, or Csk. Each sample was run in duplicate.
2011-02-17 | E-GEOD-23426 | biostudies-arrayexpress
Project description:To examine the impact of miR-146a on GC B cell development, transcriptomic profilings of total B cells isolated from unimmunized mice with B cell-specific deletion of miR-146a (B-KO) or GC B cells isolated from B-KO mice upon sheep red blood cell (SRBC) immunization were done.
2018-06-08 | GSE113975 | GEO
Project description:The expression of the Nerve growth factor receptor (NGFR) was described in follicular dendritic cells (FDCs), the major lymphoid stromal cell (LSC) compartment regulating B-cell activation within germinal centers (GCs). However, the role of NGFR in humoral response is not well defined. In this work, we have studied the effect of Ngfr KO in LNs organization and function. Ngfr KO led to spontaneous GC formation and expansion of GC B-cell compartment that were related on Ngfr depletion in non-hematopoietic radioresistant compartment. In agreement, Ngfr KO mice showed alterations in LSC with an increased frequency of FDCs harboring an activated phenotype characterized by the overexpression of CD21/35, MAdCAM-1, and VCAM-1. Moreover, Ngfr KO mice showed GC ectopic location, loss of polarization, impaired high-affinity antibody production, and increased circulating autoantibodies. In addition, Ngfr KO/Bcl2 Tg mice displayed increased levels of autoantibodies, higher incidence of autoimmunity, and decreased overall survival. Our work shows that NGFR maintains GC structure and functionality being involved in the regulation of antibody production and immune tolerance.
2023-12-13 | GSE236511 | GEO
Project description:Solid tumours are highly refractory to immune checkpoint blockade (ICB) therapies due to the functional impairment of effector T cells and their inefficient trafficking to tumours. T-cell activation is negatively regulated by C-terminal Src kinase (CSK); however, the exact mechanism remains unknown. Here we show that the conserved oncogenic tyrosine kinase Activated CDC42 kinase 1 (ACK1) is able to phosphorylate CSK at Tyrosine 18 (pY18), which enhances CSK function, constraining T-cell activation. Mice deficient in the Tnk2 gene encoding Ack1, are characterized by diminished CSK pY18 phosphorylation and spontaneous activation of CD8+ and CD4+ T cells, resulting in inhibited growth of transplanted ICB-resistant tumours. Furthermore, ICB treatment of castration-resistant prostate cancer (CRPC) patients results in re-activation of ACK1/pY18-CSK signalling, confirming the involvement of this pathway in ICB insensitivity. An ACK1 small-molecule inhibitor, (R)-9b, recapitulates inhibition of ICB-resistant tumours, which provides evidence for ACK1 enzymatic activity playing a pivotal role in generating ICB resistance. Overall, our study identifies an important mechanism of ICB resistance and holds potential for expanding the scope of ICB therapy to tumours that are currently unresponsive.
2023-03-11 | PXD037546 | Pride
Project description:Solid tumors are highly refractory to immune checkpoint blockade (ICB) therapies due to the functional impairment of the effector T cells and its trafficking back to the tumor. The T cell activation is negatively regulated by C-terminal Src kinase (CSK), however, the exact mechanism of CSK’s T cell-restraining activity remains unknown. Here, we show that the primeval oncogenic tyrosine kinase, ACK1 dampens T-cell response by augmenting CSK activity through a novel Tyr18-phosphorylation. Ack1/Tnk2-knockout mice exhibited a loss of CSK Tyr18-phosphorylation and activation of CD8+ and CD4+ T cells, compromising ICB-resistant tumor growth. Further, ICB-treated Castration-resistant prostate cancer (CRPC) patients revitalized ACK1/pY18-CSK signaling, revealing it to be the critical molecular mechanism for ICB insensitivity. Consistently, ICB-resistant tumor growth was suppressed upon treatment with a new class of ACK1 small-molecule inhibitor, (R)-9b. Interestingly, (R)-9b caused increase in leukocyte attractant, CXCL10 in cancer cells, thus navigating newly activated T cells to the tumors, creating a `self-sabotaging loop’. Overall, harnessing unique dichotomous mode of ACK1 that controls immune response of the T cells, and cytokine levels in tumor microenvironment, provides an unprecedented opportunity to sensitize immune-resistance.
2022-09-01 | GSE211835 | GEO
Project description:RNA-sequencing from sorted B cells of d16 infected mixed bone marrow chimeras. Non-GC, GC uninfected, and GC infected samples of STAT3 WT and STAT3 KO B cells from 3 independent mixed bone marrow chimera experiments.
2023-12-01 | GSE227764 | GEO
Project description:Infertility observed in adult Sertoli cell (SC)-specific Connexin 43 Knockout-mice rather seems to be an effect of the disturbed SC-Germ cell (GC) crosstalk than a direct consequence of the loss of Cx43 protein in SC with important GC specific genes being mostly affected by this deletion. Identification of differentially expressed genes in testis of cx43 KO-mice at developmental stage 8 days post partum when compared with testis of WT-mice
2011-01-06 | E-GEOD-23431 | biostudies-arrayexpress