Project description:The agonistic anti-human CD3ε antibody , OKT-3, has been used to control acute transplant rejection. The in vivo administration of OKT-3 was previously shown to induce the partial depletion of T cells and anergy in the remaining CD4+ T cells. However, this therapy is also associated with the systemic release of several cytokines, which leads to a series of adverse side effects. We established a novel anti-human CD3ε Ab, 20-2b2 (#1 abs), which recognized a close, but different determinant on the CD3ε molecule from that recognized by OKT3. 20-2b2 was non-mitogenic for human CD4+ T cells, could inhibit the activation of T cells in vitro, and induced T cell anergy in in vivo experiments using humanized mice. Cytokine release in humanized mice induced by the administration of 20-2b2 was significantly less than that induced by OKT-3. Our results indicated that the CD3ε molecule is still an attractive, effective, and useful target for the modulation of T cell responses. The establishment of other Abs that recognize CD3ε, even though the determinant recognized by those Abs may be close to or different from that recognized by OKT-3, may represent a novel approach for the development of safer Ab therapies using anti-CD3 Abs, in addition to the modification of OKT-3 in terms of the induction of cytokine production.
Project description:Purpose: The aim of this study is the evaluation of differential gene expression profile by RNA-seq in response to anti-CD3 treatment in CD3 cells obtained from blood samples of healthy donors, to achieve a better understanding of the antibodies molecular mechanisms of action. In this study T cells were treated in the complex PBMC milieu, in a tentative to mimetize the natural ambient that occurs in a clinical administration of therapeutic anti-CD3. Methods: Human peripheral blood mononuclear cells were purified from healthy volunteers blood and were cultured in the presence of the monoclonal antibody OKT3 or a recombinant fragment of humanized anti-CD3 (FvFcR) or recombinant fragment chimeric anti-CD3 (FvFcM). After 72 hours, CD3+ T cells were isolated by negative selection using magnetic beads and total RNA was extracted with the RNeasy kit (Qiagen). Paired-end cDNA reads (150bp) were generated using the HiSeq 2500 Sequencing system (Illumina) located at the NGS Overseas Project Manager, Next Generation Sequencing Division, Macrogen, Inc. (Seoul, Korea). Quality check of the paired-end reads was performed using FASTQC. The reads were aligned to the human genome refence downloaded from the UCSC Genome Browser database using open source segemehl_0_2_0. The aligned files were ordered and indexed using Samtools followed by read count using HTSeq-count. Statistical analysis was done using the R environment for statistical computing. Gene model quantification were performed using the Bioconductor package DESeq2. Results: Using an optimized data analysis workflow, we mapped about 50 million sequence reads per sample to the human genome and identified 7089 transcripts in the T cell stimulated with OKT3, 2425 transcripts with FvFc R and 1406 with FvFc M. RNA-seq data confirmed stable expression of some known housekeeping genes, and 3 of these were validated with qRT-PCR. We found 860 genes there are equally regulated among the treatments, considering a padj ≤ 0.05. Altered expression of 35 genes was confirmed with qRT-PCR, demonstrating the high degree of sensitivity of the RNA-seq method. Conclusions: In conclusion, we had used a deep transcriptome sequencing method for comparing three anti-CD3 antibodies in terms of gene ontology enrichment and immunological markers expression. The present data showed that both recombinant antibodies induced a compatible expression profile, suggesting they could be tested as substitute in human pre-clinical trials. Moreover, the proposed methodology is amenable to be more generally applied for molecular comparison purposes.
Project description:Nasal administration of anti-CD3 monoclonal antibody (Foralumab) modulates effector CD8+ T cell function and induces a regulatory response in T cells in human subjects
Project description:Mouse CD8 T cells were isolated from total splenocytes from C57BL/6 mice by MACS separation. Cells were incubated for 48 h with CD3/CD28 DynaBeads and 50 ng/ml IL-2 for 48 h with or without 100 nm anti-CD132 blocking antibody. Cells were collected and RNA was isolated.
Project description:Engagement of the ICOS receptor represents a key event in a process that culminates in Bcl6 expression and acquisition of the TFH and TFR phenotype. To better understand the essentials of ICOS-mediated signaling pathway, we profiled the changes in gene expression elicited after co-ligation of ICOS and CD3 compared with CD3 ligation alone. Naïve CD4+ T-cells were purified from single cell suspensions of B6 spleen and stimulated with anti-CD3 and anti-CD28 for 2d followed by resting overnight before 20 min of incubation with anti-CD3 and/or anti-ICOS and cross-linking with goat anti-hamster Ab for 8h. RNA was prepared, amplified, labeled and hybridized to Mouse Gene 1.0 ST Array (Affymetrix), in quadruplicates for anti-CD3 ligation and duplicates for anti-CD3/ anti-ICOS co-ligation.
Project description:KY1044 is a human monoclonal IgG1 that selectively binds to Inducible T cell CO-stimulator (ICOS). The co-stimulatory effect of KY1044-stimulated human T cells was analysed by RNA sequencing (RNA seq). Purified pre-activated (ICOS+ve) T cells were stimulated with either KY1044 and anti-CD3 or anti-CD3 alone and cells were harvested for RNA seq after 6hrs. Kallisto transcript abundance are provided in the absence of raw sequence reads.
Project description:compare gene expression profiles between normal and anergic T cells and identify upregulated genes in anergic T cells Experiment Overall Design: RNA from normal Th1 T cell clone and anergic Th1 T cell clone made anergic by plate-bound anti-CD3 antibody were isolated and amplified for microarray analysis
Project description:Type 1 diabetes (T1D) results from autoimmune destruction of β cells in the pancreas. Protein tyrosine phosphatases (PTPs) are candidate genes for T1D and play a key role in autoimmune disease development and β-cell function. Here, we assessed the global protein and individual PTP profile in the pancreas of diabetic NOD mice treated with anti-CD3 mAb and IL-1RA combination therapy. The treatment reversed hyperglycemia compared to the anti-CD3 alone control group. We observed enhanced expression of PTPN2, a T1D candidate gene, and endoplasmic reticulum (ER) chaperones in the islets from cured mice.
Project description:CD3-bispecific antibodies represent an important therapeutic strategy in oncology. These molecules work by redirecting cytotoxic T cells to antigen-bearing tumor cells. Although CD3-bispecific antibodies have been developed for several clinical indications, cases of cancer-derived resistance are an emerging limitation to the more generalized application of these molecules. Here, we devised whole-genome CRISPR screens to identify cancer resistance mechanisms to CD3-bispecific antibodies across multiple targets and cancer types. By validating the screen hits, we found that deficiency in IFNγ signaling has a prominent role in cancer resistance. Interestingly, IFNγ functions by stimulating the expression of T cell killing-related molecules in a cell type-specific manner. Additionally, by assessing resistance to the clinical CD3-bispecific antibody flotetuzumab, we identified core fucosylation as a novel and critical pathway to regulate flotetuzumab binding to the CD123 antigen. Disruption of this pathway resulted in significant resistance to flotetuzumab treatment. Moreover, proper fucosylation of CD123 is required for its normal biological functions. In order to treat the resistance associated with fucosylation loss, flotetuzumab in combination with an alternative targeting CD3-bispecific antibody demonstrated superior efficacy. Together, our study reveals multiple mechanisms that can be targeted to enhance the clinical potential of current and future T cell engaging CD3-bispecific antibody therapies.