Project description:Here, we systematically profile the methylation sensitivity of 18 human TFs spanning 11 structural families using chemically synthesized DNA libraries containing position-specific 5-methylcytosines (5mC) in CpG, non-CpG, and hemi-methylated contexts, measured via high-throughput protein-binding microarrays. Our results reveal extensive TF sensitivity to methylation state, position, and strand orientation—including strong binding of several TFs to non-CpG and hemi-methylated sites. The presence of 5mC can dramatically alter TF-DNA interactions: transforming low-affinity sites into high-affinity ones by enabling new contacts, or silencing otherwise favorable motifs through steric hindrance. Genomic analyses further show that the methylation-sensitive sequences identified in vitro are represented within enhancers and regulatory elements, exhibiting distinct methylation patterns across cell types. Together, our findings uncover a previously hidden layer of methylation-dependent TF-DNA recognition, broadening the understanding of epigenetics in transcriptional regulation.
Project description:Human antibody responses to AM/LAM are heterogenous and knowledge of reactivity to specific glycan epitopes at the monoclonal level is limited. Using novel glycan arrays, we characterized very high affinity monoclonal antibodies to AM/LAM, determined these mAbs are non-competing, and recognized distinct glycan epitopes. distinct from other anti-AM/LAM mAbs reported.
Project description:Examine protein phosphorylation status during peripheral nerve regeneration when using autologous nerve graft or tissue engineered nerve graft to bridge nerve gap.
Project description:This study employed the NanoString nCounter platform to perform targeted, quantitative molecular profiling of longitudinally collected FFPE tumor samples to elucidate molecular mechanisms underlying resistance to anti–PD-1 therapy. nCounter® Vantage 3D™ Single Nucleotide Variant assay was integrated using a solid tumor panel to screen 104 driver variants across 25 genes frequently mutated in solid tumors. We quantified the expression of 770 cancer-related mRNA transcripts to identify persistently activated oncogenic pathway signatures in non-responders, which were further complemented by quantitative profiling of 27 total and phosphoproteins using antibody–oligonucleotide conjugates for functional validation of pathway activity. To characterize the tumor microenvironment spatially, GeoMx Digital Spatial Profiler analysis was utilized to assess the distribution of 38 proteins across distinct histological regions, revealing an immunosuppressive spatial architecture associated with treatment resistance.
Project description:Endoglin (EDG) is a cell surface protein with an important role in the establishment of neo-angiogenesis and vasculogenic mimicry. EDG is part of the transforming growth factor-β (TGF-β) family, acting as an important co-receptor. EDG is shed from the cell surface into the extracellular compartment by matrix metalloproteinase 14 (MMP14), in its soluble form (sEDG). Both transmembrane and soluble forms of EDG exert important signaling functions in the development of new blood vessels and tumour progression. To better understand the role of EDG in Ewing sarcoma (ES), a deadly neoplasm of late childhood and adolescence, we test the efficacy of OMTX703, an endoglin-targeting antibody-drug conjugate in ES8 xenograft. Having determined an optimal dose for OMTX703, an additional experiment was conducted to assess the mechanism(s) of OMTX703 action and its potential mechanism(s) of resistance following a 2-week exposure to OMTX703 at 0, 10, 30, and 60 mg/kg; 246 proteins were assessed by reverse-phase protein array (RPPA). Analysis of variance (ANOVA), Pearson’s correlation as distance metric and Ward’s linkage as the clustering method using a false discovery rate (FDR) of 0.01, identified 60 proteins that discriminated between treatment groups (Matrix#1-Normalized Values). To investigate the proteomic changes associated with the heightened clinical activity of the 60 mg/kg dose, a secondary analysis was performed, which grouped the 10 mg/kg OMTX703 samples and the 10 mg/kg OMTX003 ones with the placebo-treated samples (Matrix#2-Normalized Values). Using a FDR of 0.0001, an absolute log2 fold change of 1.5, Pearson’s correlation as distance metric and Ward’s linkage as the clustering method, 22 proteins were discriminately identified between the 3 treatment groups (Matrix#2-Normalized Values). Notably, a protein regulator of altered metabolism (RPS6) was exclusively upregulated following OMTX703 (60mg/kg), and a second metabolism biomarker (LDHA) was down-expressed in the 30 and 60 mg/kg-treated groups. Conversely, BRD4 was one of about a dozen proteins that were preferentially down-regulated in samples treated only by 60 mg/kg.
Project description:Introduction: Serous ovarian cancer is the leading cause of gynecological cancers, with a 5-year survival rate below 45% due in part to the nonspecific symptoms and lack of accurate screening for early detection. In comparison, patients diagnosed at an early stage have a five-year survival rate of 92%, demonstrating the urgent need for biomarkers for the early detection of disease. Serum from patients with serous ovarian cancer contain antibodies to tumor antigens that are potential biomarkers for early detection. The purpose of this study is to identify a panel of novel serum autoantibody (AAb) biomarkers for the early diagnosis of serous ovarian cancer. Methods: To detect AAb we probed high-density programmable protein microarrays (NAPPA) containing 10,247 antigens with sera from patients with serous ovarian cancer (n = 30 cases/ 30 healthy controls) and measured bound IgG. We identified 735 promising tumor antigens using cutoff values of 10% sensitivity at 95% specificity and K-value>0.8, as well as visual analysis and evaluated these with an independent set of serous ovarian cancer sera (n = 30 cases/ 30 benign disease controls/ 30 heathy controls). Thirty-nine potential tumor autoantigens were identified with sensitivities ranging from 3 to 39.7% sensitivity at 95% specificity and were retested using an orthogonal programmable ELISA assay. A total of 13 potential tumor antigens were identified for further validation using an independent ovarian cancer sera set (n = 44 cases/ 34 healthy controls). Sensitivities at 95% specificity were calculated and a serous ovarian cancer classifier was constructed. In addition, we evaluated a longitudinal study using blinded serous pre-diagnostic ovarian cancer sera (n = 9 cases/ 90 controls) to examine the value of three (CTAG1, CTAG2, and p53) of these AAb in comparison to CA 125. Results: We identified 11-AAbs (ICAM3, CTAG2, p53, STYXL1, PVR, POMC, NUDT11, TRIM39, UHMK1, KSR1, and NXF3) that distinguished serous ovarian cancer cases from healthy controls with a combined 45% sensitivity at 100% specificity. In our longitudinal analysis, p53- and CTAG-AAb were detected up to 9 months prior to ovarian cancer diagnosis and increased with CA 125 levels. Conclusion: These are potential circulating biomarkers for the early detection of serous ovarian cancer, and warrant confirmation in larger clinical cohorts. In addition, p53- and CTAG1/2-AAb are detected in a subset of women with ovarian cancer up to 9 months prior to clinical diagnosis. Their utility as a biomarker for early detection, beyond CA 125, warrant further investigation.
Project description:Leptospirosis is zoonotic disease of global importance, with over a million cases andnearly 60,000 deaths annually. Symptomatic disease presentation ranges from a mildfebrile disease with non-specific symptoms to severe forms, characterized by multi-organ failure, lung hemorrhage, and death. Factors governing severe outcomes remainunclear, but the host immune response likely plays an important role. In the presentstudy, we applied high throughput techniques to identify the antibody profiles ofpatients with severe and mild leptospirosis. We discovered a limited number ofimmunodominant antigens, specific to patients. Surprisingly, we found the antibodyrepertoire varies in patients with different clinical outcomes and hypothesized thatpatients with mild symptoms were protected from severe disease due to pre-existingantibodies, while the profile of patients with severe outcomes was representative of afirst exposure. These findings represent a substantial step forward in the knowledge ofthe humoral immune response to Leptospira infection, and we have identified newtargets for vaccine and diagnostic test development.
Project description:Systemic lupus erythematosus is a chronic autoimmune disease with multifactorial ethiopathogenesis. The complement system is involved in both the early and late stages of disease development and organ damage. To better understand autoantibody mediated complement consumption the GAPAID consortium examined ex vivo immune complex formation on autoantigen arrays. We recruited patients with SLE (n=211), with other systemic autoimmune diseases (n=65) and non-autoimmune control subjects (n=149) in two rheumatology tertiary care centers. Standard clinical and laboratory data were collected from all subjects and serum complement levels were determined in SLE patients. The genotype of SNP rs1143679 in the ITGAM gene was also determined. On-chip formation of immune complexes was examined using a functional immunoassay on autoantigen microarray. The amount of antigen-bound IgM, IgG and complement C4 and C3 was quantified on autoantigens comprising nucleic acids, proteins and lipids. Our results show that the relatively high complement consumption of nucleic acids is further increased upon binding of IgM and IgG. This is true even when serum complement levels are decreased due to complement consumption in SLE patients. A negative correlation between serum complement levels and ex vivo complement deposition on nucleic acid autoantigens is demonstrated. On the contrary, most protein and lipid autoantigens show positive correlation with C4 and C3 levels. Genetic analysis reveals that the non-synonymous variant rs1143679 in complement receptor type 3 is associated with an increased production of anti-dsDNA IgG antibodies. Notwithstanding, homozygous carriers of the previously reported susceptible allele (AA) have lower levels of dsDNA specific IgM among SLE patients. Regarding organ involvement we find that besides anti-C1q IgG, low levels of dsDNA specific IgM and low complement C4 binding to C1q are also associated with renal injury. In summary, nucleic acids maintain a skewed complement deposition balance when bound by IgG and IgM, depleting the early classical complement pathway from other physiological processes. Dysfunction of the receptor responsible for complement-mediated apoptotic debris removal promotes the development of autoantibodies targeting nucleic acids. These observations provide serological and genetic evidence for complement-mediated clearance deficiency of apoptotic debris in lupus.