Aikun Fu Similar Datasets
Project description:Analysis of germinal center B cells derived from WT and SAP-deficient mice revealed that SAP-deficient mice have reduced Myc signature
2019-12-28 | GSE142640 | GEO
Project description:Total RNAs were extracted from internodes and roots of 18 day-after-germination soybean plants, and the expression levels of the genes that encode xylem sap associated peptides or proteins were analyzed.
2015-10-23 | E-MTAB-5052 | biostudies-arrayexpress
Project description:The central nervous system (CNS), despite the presence of strategically positioned anatomical barriers designed to protect it, is not entirely isolated from the immune system. In fact, it remains physically connected to and can be influenced by the peripheral immune system. How the CNS retains such responsiveness while maintaining “immune privilege” remains an outstanding conundrum. In searching for molecular cues that derive from the CNS and allow its direct communication with the immune system, we discovered a repertoire of CNS-derived endogenous guardian peptides presented on major histocompatibility complex (MHC) II molecules at the CNS borders. During homeostasis, a preponderance of these guardian peptides were found to be bound to MHC II molecules throughout the path of lymphatic drainage from the brain to its surrounding meninges and its draining cervical lymph nodes. With neuroinflammatory disease, however, the presentation of guardian peptides was diminished. Fascinatingly, boosting the presence of these guardian peptides reinforced a population of suppressor CD4+ T cells and significantly reduced CNS autoimmune disease. This unexpected discovery of CNS-derived autoimmune guardian peptides may be the molecular key adapting the CNS to receive information and to maintain continuous dialogue with the immune system while balancing overt autoreactivity. This sheds new light on how we conceptually think about and therapeutically target neuroinflammatory and neurodegenerative diseases.
2024-10-11 | GSE240691 | GEO
Project description:MHC I-peptides (MIPs) play an essential role in normal homeostasis and diverse pathological conditions. MIPs derive mainly from defective ribosomal products (DRiPs), a subset of nascent proteins that fail to achieve a proper conformation and whose physical nature remains elusive. We used high-throughput proteomic and transcriptomic methods to unravel the structure and biogenesis of MIPs presented by HLA-A and -B molecules on human EBV-infected B lymphocytes from four subjects. We found that although HLA-different subjects present different MIPs derived from different proteins, these MIPs originate from proteins that are functionally interconnected and implicated in similar biological pathways. Secondly, the MIP repertoire of human B cells showed no bias toward conserved vs. polymorphic genomic sequences, derived preferentially from abundant transcripts and conveyed to the cell surface a cell type-specific signature. Finally, we discovered that MIPs derive preferentially from transcripts bearing miRNA response elements. Furthermore, while MIPs of HLA-disparate subjects are coded by different sets of transcripts, these transcripts are regulated by mostly similar miRNAs. Our data support an emerging model in which i) the generation of MIPs by a transcript depends on its abundance and DRiP rate, and ii) the DRiP rate is regulated to a large extent by miRNAs. We performed genome-wide miRNA expression profiling of B cells and non-lymphoid cells to confirm that miRNAs predicted to regulate transcripts source of MHC I-associated peptides are expressed in a cell-specific manner. miRNA profiling was done on (i) 4 B-lymphoblastoid cell lines (B-LCLs) obtained from the peripheral blood mononuclear cells of 4 subjects, (ii) CD19+CD20- B cells and CD19+CD20+ B cells of one of the subjects, (iii) HeLa cells, and (iv) HEK293 cells.
2012-03-25 | E-GEOD-35319 | biostudies-arrayexpress
Project description:The immune response against tuberculosis relies, at least in part, on CD4+ T cells. Protective vaccines require the induction of antigen-specific CD4+ T cells via mycobacterial peptides presented by MHC class-II in infected macrophages. We have purified MHC class-I and MHC-II peptides and analysed them by mass spectrometry. We have successfully identified 97 mycobacterial peptides presented by MHC-II and 54 presented by MHC-I, from 76 and 41 antigens, respectively. The sequences of selected peptides were confirmed by spectral match validation and immunogenicity evaluated by IFN-gamma ELISpot against peripheral blood mononuclear cells from volunteers vaccinated with BCG, M.tb latently infected subjects or patients with tuberculosis disease. Three antigens were expressed in viral vectors, and evaluated as vaccine candidates alone or in combination in a murine aerosol M.tb challenge model. When delivered in combination, the three candidate vaccines conferred significant protection in the lungs and spleen compared with BCG alone, demonstrating proof-of-concept for this unbiased approach to identifying novel candidate antigens.
2020-01-08 | E-MTAB-8057 | biostudies-arrayexpress
Project description:To identify the endogenous peptides presented by MHC-Ⅰa and Qa-1 molecules on activated CD4+ T cells
2024-08-31 | PXD055454 |
Project description:MHC I-peptides (MIPs) play an essential role in normal homeostasis and diverse pathological conditions. MIPs derive mainly from defective ribosomal products (DRiPs), a subset of nascent proteins that fail to achieve a proper conformation and whose physical nature remains elusive. We used high-throughput proteomic and transcriptomic methods to unravel the structure and biogenesis of MIPs presented by HLA-A and -B molecules on human EBV-infected B lymphocytes from four subjects. We found that although HLA-different subjects present different MIPs derived from different proteins, these MIPs originate from proteins that are functionally interconnected and implicated in similar biological pathways. Secondly, the MIP repertoire of human B cells showed no bias toward conserved vs. polymorphic genomic sequences, derived preferentially from abundant transcripts and conveyed to the cell surface a cell type-specific signature. Finally, we discovered that MIPs derive preferentially from transcripts bearing miRNA response elements. Furthermore, while MIPs of HLA-disparate subjects are coded by different sets of transcripts, these transcripts are regulated by mostly similar miRNAs. Our data support an emerging model in which i) the generation of MIPs by a transcript depends on its abundance and DRiP rate, and ii) the DRiP rate is regulated to a large extent by miRNAs. We performed genome-wide miRNA expression profiling of B cells and non-lymphoid cells to confirm that miRNAs predicted to regulate transcripts source of MHC I-associated peptides are expressed in a cell-specific manner.
2012-03-25 | GSE35319 | GEO
Project description:Over the past three decades, the Hunt laboratory has developed advancements in mass spectrometry-based technologies to enable the identification of peptides bound to major histocompatibility complex (MHC) molecules. The MHC class I processing pathway is responsible for presenting these peptides to circulating cytotoxic T cells, allowing them to recognize and eliminate malignant cells, many of which have aberrant signaling. Professor Hunt hypothesized that due to the dysregulation in phosphorylation in cancer, that abnormal phosphopeptides are likely presented by this pathway, and went on to discover the first phosphopeptide presented by the MHC processing pathway. Thereafter, the laboratory continued to sequence MHC-associated phosphopeptides and contributed several improved methods for their enrichment, detection, and sequencing. This manuscript summarizes the most recent advancements in identification of modified MHC-associated peptides and includes the cumulative list of phosphopeptides sequenced by the Hunt lab. Further, many other post-translational modifications (PTMs) were found to modify MHC peptides, including O-GlcNAcylation, methylation, and kynurenine; in total, we present here a list of 2,450 MHC-associated PTM peptides. Many of these were disease specific and found across several patients, thus highlighting their potential as cancer immunotherapy targets. We are sharing this list with the field in hopes that it might be used in investigating this potential. Overall, the Hunt lab’s contributions have significantly advanced our understanding of antigen presentation and dysregulation of PTMs, supporting modern immunotherapy and vaccine development efforts.
2025-04-15 | PXD061414 | Pride
Project description:We developed a novel approach combining next generation sequencing, bioinformatics and mass spectrometry to assess the impact of non-MHC polymorphisms on the repertoire of MHC I-associated peptides (MIPs). We compared the genomic landscape of MIPs eluted from B lymphoblasts of two MHC-identical siblings and determined that MIPs mirror the genomic frequency of non-synonymous polymorphisms but they behave as recessive traits at the surface level. Moreover, we showed that 11.7% of the MIP coding exome is polymorphic at the population level. Our method provides fundamental insights into the relation between the genomic self and the immune self and accelerates the discovery of polymorphic MIPs (also known as minor histocompatibility antigens), which play a major role in allo-immune responses. RNA-seq of human B lymphoblasts derived from peripheral blood mononuclear cells from 2 HLA-identical female siblings.
2013-12-08 | E-GEOD-48918 | biostudies-arrayexpress
Project description:Identification of antigens presented by MHC for vaccines against tuberculosis
| PRJEB33057 | ENA