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Stern LJ, Clement C, Galluzzi L, Santambrogio L. Non-mutational neoantigens in disease. Nat Immunol 2024; 25:29-40. [PMID: 38168954 PMCID: PMC11075006 DOI: 10.1038/s41590-023-01664-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Accepted: 09/29/2023] [Indexed: 01/05/2024]
Abstract
The ability of mammals to mount adaptive immune responses culminating with the establishment of immunological memory is predicated on the ability of the mature T cell repertoire to recognize antigenic peptides presented by syngeneic MHC class I and II molecules. Although it is widely believed that mature T cells are highly skewed towards the recognition of antigenic peptides originating from genetically diverse (for example, foreign or mutated) protein-coding regions, preclinical and clinical data rather demonstrate that novel antigenic determinants efficiently recognized by mature T cells can emerge from a variety of non-mutational mechanisms. In this Review, we describe various mechanisms that underlie the formation of bona fide non-mutational neoantigens, such as epitope mimicry, upregulation of cryptic epitopes, usage of non-canonical initiation codons, alternative RNA splicing, and defective ribosomal RNA processing, as well as both enzymatic and non-enzymatic post-translational protein modifications. Moreover, we discuss the implications of the immune recognition of non-mutational neoantigens for human disease.
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Affiliation(s)
- Lawrence J Stern
- Department of Pathology, UMass Chan Medical School, Worcester, MA, USA
- Immunology and Microbiology Program, UMass Chan Medical School, Worcester, MA, USA
| | - Cristina Clement
- Department of Radiation Oncology, Weill Cornell Medical College, New York, NY, USA
| | - Lorenzo Galluzzi
- Department of Radiation Oncology, Weill Cornell Medical College, New York, NY, USA.
- Sandra and Edward Meyer Cancer Center, New York, NY, USA.
- Caryl and Israel Englander Institute for Precision Medicine, New York, NY, USA.
| | - Laura Santambrogio
- Department of Radiation Oncology, Weill Cornell Medical College, New York, NY, USA.
- Sandra and Edward Meyer Cancer Center, New York, NY, USA.
- Caryl and Israel Englander Institute for Precision Medicine, New York, NY, USA.
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2
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Siddiqui K, Nawaz SS. Exploration of Immune Targets for Type 1 Diabetes and Latent Autoimmune Disease Immunotherapy. Immunotargets Ther 2023; 12:91-103. [PMID: 37795196 PMCID: PMC10546931 DOI: 10.2147/itt.s417917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2023] [Accepted: 09/09/2023] [Indexed: 10/06/2023] Open
Abstract
Type 1 diabetes (T1D) is an autoimmune disease that destroys pancreatic beta cells, which produce insulin in the islets of Langerhans. The risk of developing T1D is influenced by environmental factors, genetics, and autoantibodies. Latent autoimmune diabetes in adults (LADA) is a type of T1D that is genetically and phenotypically distinct from classic T1D. This review summarizes the accumulated information on the risk factors for T1D and LADA, and immunotherapy trials that offer insights into potential future combined therapeutic interventions for both T1D and LADA to slow the rate of islet cell loss and preserve beta cell function. Future research should also focus on improving intervention doses, conducting more thorough examinations of intervention responders, and/or combining minimally effective single-target immunotherapies to slow the rate of islet cell loss and preserve beta cell function.
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Affiliation(s)
- Khalid Siddiqui
- Strategic Center for Diabetes Research, College of Medicine, King Saud University, Riyadh, Saudi Arabia
| | - Shaik Sarfaraz Nawaz
- Strategic Center for Diabetes Research, College of Medicine, King Saud University, Riyadh, Saudi Arabia
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3
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Role of the Intermediate Filament Protein Peripherin in Health and Disease. Int J Mol Sci 2022; 23:ijms232315416. [PMID: 36499746 PMCID: PMC9740141 DOI: 10.3390/ijms232315416] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 11/23/2022] [Accepted: 12/02/2022] [Indexed: 12/12/2022] Open
Abstract
Intermediate filaments are the most heterogeneous class among cytoskeletal elements. While some of them have been well-characterized, little is known about peripherin. Peripherin is a class III intermediate filament protein with a specific expression in the peripheral nervous system. Epigenetic modifications are involved in this cell-type-specific expression. Peripherin has important roles in neurite outgrowth and stability, axonal transport, and axonal myelination. Moreover, peripherin interacts with proteins involved in vesicular trafficking, signal transduction, DNA/RNA processing, protein folding, and mitochondrial metabolism, suggesting a role in all these processes. This review collects information regarding peripherin gene regulation, post-translational modifications, and functions and its involvement in the onset of a number of diseases.
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do Carmo Neto JR, Braga YLL, da Costa AWF, Lucio FH, do Nascimento TC, dos Reis MA, Celes MRN, de Oliveira FA, Machado JR, da Silva MV. Biomarkers and Their Possible Functions in the Intestinal Microenvironment of Chagasic Megacolon: An Overview of the (Neuro)inflammatory Process. J Immunol Res 2021; 2021:6668739. [PMID: 33928170 PMCID: PMC8049798 DOI: 10.1155/2021/6668739] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2020] [Revised: 03/08/2021] [Accepted: 03/19/2021] [Indexed: 12/13/2022] Open
Abstract
The association between inflammatory processes and intestinal neuronal destruction during the progression of Chagasic megacolon is well established. However, many other components play essential roles, both in the long-term progression and control of the clinical status of patients infected with Trypanosoma cruzi. Components such as neuronal subpopulations, enteric glial cells, mast cells and their proteases, and homeostasis-related proteins from several organic systems (serotonin and galectins) are differentially involved in the progression of Chagasic megacolon. This review is aimed at revealing the characteristics of the intestinal microenvironment found in Chagasic megacolon by using different types of already used biomarkers. Information regarding these components may provide new therapeutic alternatives and improve the understanding of the association between T. cruzi infection and immune, endocrine, and neurological system changes.
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Affiliation(s)
- José Rodrigues do Carmo Neto
- Department of Bioscience and Technology, Institute of Tropical Pathology and Public Health, Federal University of Goiás, Goiânia, GO, Brazil
| | - Yarlla Loyane Lira Braga
- Department of Bioscience and Technology, Institute of Tropical Pathology and Public Health, Federal University of Goiás, Goiânia, GO, Brazil
| | - Arthur Wilson Florêncio da Costa
- Department of Bioscience and Technology, Institute of Tropical Pathology and Public Health, Federal University of Goiás, Goiânia, GO, Brazil
| | - Fernanda Hélia Lucio
- Department of Bioscience and Technology, Institute of Tropical Pathology and Public Health, Federal University of Goiás, Goiânia, GO, Brazil
| | - Thais Cardoso do Nascimento
- Department of Bioscience and Technology, Institute of Tropical Pathology and Public Health, Federal University of Goiás, Goiânia, GO, Brazil
| | - Marlene Antônia dos Reis
- Department of General Pathology, Federal University of Triângulo Mineiro, Uberaba, Minas Gerais, Brazil
| | - Mara Rubia Nunes Celes
- Department of Bioscience and Technology, Institute of Tropical Pathology and Public Health, Federal University of Goiás, Goiânia, GO, Brazil
| | - Flávia Aparecida de Oliveira
- Department of Bioscience and Technology, Institute of Tropical Pathology and Public Health, Federal University of Goiás, Goiânia, GO, Brazil
| | - Juliana Reis Machado
- Department of Bioscience and Technology, Institute of Tropical Pathology and Public Health, Federal University of Goiás, Goiânia, GO, Brazil
- Department of General Pathology, Federal University of Triângulo Mineiro, Uberaba, Minas Gerais, Brazil
| | - Marcos Vinícius da Silva
- Department of Microbiology, Immunology and Parasitology, Institute of Biological and Natural Sciences, Federal University of Triângulo Mineiro, Uberaba, Minas Gerais, Brazil
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5
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Morimoto J, Sando S. Peptoids with Substituents on the Backbone Carbons as Conformationally Constrained Synthetic Oligoamides. J SYN ORG CHEM JPN 2020. [DOI: 10.5059/yukigoseikyokaishi.78.1076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
| | - Shinsuke Sando
- Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo
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6
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Racine JJ, Chapman HD, Doty R, Cairns BM, Hines TJ, Tadenev ALD, Anderson LC, Green T, Dyer ME, Wotton JM, Bichler Z, White JK, Ettinger R, Burgess RW, Serreze DV. T Cells from NOD- PerIg Mice Target Both Pancreatic and Neuronal Tissue. THE JOURNAL OF IMMUNOLOGY 2020; 205:2026-2038. [PMID: 32938729 DOI: 10.4049/jimmunol.2000114] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 08/13/2020] [Indexed: 11/19/2022]
Abstract
It has become increasingly appreciated that autoimmune responses against neuronal components play an important role in type 1 diabetes (T1D) pathogenesis. In fact, a large proportion of islet-infiltrating B lymphocytes in the NOD mouse model of T1D produce Abs directed against the neuronal type III intermediate filament protein peripherin. NOD-PerIg mice are a previously developed BCR-transgenic model in which virtually all B lymphocytes express the H and L chain Ig molecules from the intra-islet-derived anti-peripherin-reactive hybridoma H280. NOD-PerIg mice have accelerated T1D development, and PerIg B lymphocytes actively proliferate within islets and expand cognitively interactive pathogenic T cells from a pool of naive precursors. We now report adoptively transferred T cells or whole splenocytes from NOD-PerIg mice expectedly induce T1D in NOD.scid recipients but, depending on the kinetics of disease development, can also elicit a peripheral neuritis (with secondary myositis). This neuritis was predominantly composed of CD4+ and CD8+ T cells. Ab depletion studies showed neuritis still developed in the absence of NOD-PerIg CD8+ T cells but required CD4+ T cells. Surprisingly, sciatic nerve-infiltrating CD4+ cells had an expansion of IFN-γ- and TNF-α- double-negative cells compared with those within both islets and spleen. Nerve and islet-infiltrating CD4+ T cells also differed by expression patterns of CD95, PD-1, and Tim-3. Further studies found transitory early B lymphocyte depletion delayed T1D onset in a portion of NOD-PerIg mice, allowing them to survive long enough to develop neuritis outside of the transfer setting. Together, this study presents a new model of peripherin-reactive B lymphocyte-dependent autoimmune neuritis.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Zoë Bichler
- The Jackson Laboratory, Bar Harbor, ME 04609
| | | | - Rachel Ettinger
- Viela Bio, Gaithersburg, MD 20878; and.,Respiratory, Inflammation, and Autoimmunity, BioPharmaceuticals R&D, AstraZeneca, Gaithersburg, MD 20878
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7
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McEnaney P, Balzarini M, Park H, Kodadek T. Structural characterization of a peptoid-inspired conformationally constrained oligomer (PICCO) bound to streptavidin. Chem Commun (Camb) 2020; 56:10560-10563. [PMID: 32785302 DOI: 10.1039/d0cc02588g] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A high affinity Streptavidin ligand was mined from a DNA-encoded library of non-peptidic oligimers and characterized structurally.
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Affiliation(s)
- Patrick McEnaney
- Department of Chemistry, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 3345, USA.
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8
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Type III intermediate filaments as targets and effectors of electrophiles and oxidants. Redox Biol 2020; 36:101582. [PMID: 32711378 PMCID: PMC7381704 DOI: 10.1016/j.redox.2020.101582] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 05/05/2020] [Accepted: 05/13/2020] [Indexed: 12/20/2022] Open
Abstract
Intermediate filaments (IFs) play key roles in cell mechanics, signaling and homeostasis. Their assembly and dynamics are finely regulated by posttranslational modifications. The type III IFs, vimentin, desmin, peripherin and glial fibrillary acidic protein (GFAP), are targets for diverse modifications by oxidants and electrophiles, for which their conserved cysteine residue emerges as a hot spot. Pathophysiological examples of these modifications include lipoxidation in cell senescence and rheumatoid arthritis, disulfide formation in cataracts and nitrosation in endothelial shear stress, although some oxidative modifications can also be detected under basal conditions. We previously proposed that cysteine residues of vimentin and GFAP act as sensors for oxidative and electrophilic stress, and as hinges influencing filament assembly. Accumulating evidence indicates that the structurally diverse cysteine modifications, either per se or in combination with other posttranslational modifications, elicit specific functional outcomes inducing distinct assemblies or network rearrangements, including filament stabilization, bundling or fragmentation. Cysteine-deficient mutants are protected from these alterations but show compromised cellular performance in network assembly and expansion, organelle positioning and aggresome formation, revealing the importance of this residue. Therefore, the high susceptibility to modification of the conserved cysteine of type III IFs and its cornerstone position in filament architecture sustains their role in redox sensing and integration of cellular responses. This has deep pathophysiological implications and supports the potential of this residue as a drug target. Type III intermediate filaments can be modified by many oxidants and electrophiles. Oxidative modifications of type III IFs occur in normal and pathological conditions. The conserved cysteine residue acts as a hub for redox/electrophilic modifications. Cysteine modifications elicit structure-dependent type III IF rearrangements. Type III intermediate filaments act as sensors for oxidative and electrophilic stress.
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9
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Purcell AW, Sechi S, DiLorenzo TP. The Evolving Landscape of Autoantigen Discovery and Characterization in Type 1 Diabetes. Diabetes 2019; 68:879-886. [PMID: 31010879 PMCID: PMC6477901 DOI: 10.2337/dbi18-0066] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 01/29/2019] [Indexed: 12/20/2022]
Abstract
Type 1 diabetes (T1D) is an autoimmune disease that is caused, in part, by T cell-mediated destruction of insulin-producing β-cells. High risk for disease, in those with genetic susceptibility, is predicted by the presence of two or more autoantibodies against insulin, the 65-kDa form of glutamic acid decarboxylase (GAD65), insulinoma-associated protein 2 (IA-2), and zinc transporter 8 (ZnT8). Despite this knowledge, we still do not know what leads to the breakdown of tolerance to these autoantigens, and we have an incomplete understanding of T1D etiology and pathophysiology. Several new autoantibodies have recently been discovered using innovative technologies, but neither their potential utility in monitoring disease development and treatment nor their role in the pathophysiology and etiology of T1D has been explored. Moreover, neoantigen generation (through posttranslational modification, the formation of hybrid peptides containing two distinct regions of an antigen or antigens, alternative open reading frame usage, and translation of RNA splicing variants) has been reported, and autoreactive T cells that target these neoantigens have been identified. Collectively, these new studies provide a conceptual framework to understand the breakdown of self-tolerance, if such modifications occur in a tissue- or disease-specific context. A recent workshop sponsored by the National Institute of Diabetes and Digestive and Kidney Diseases brought together investigators who are using new methods and technologies to identify autoantigens and characterize immune responses toward these proteins. Researchers with diverse expertise shared ideas and identified resources to accelerate antigen discovery and the detection of autoimmune responses in T1D. The application of this knowledge will direct strategies for the identification of improved biomarkers for disease progression and treatment response monitoring and, ultimately, will form the foundation for novel antigen-specific therapeutics. This Perspective highlights the key issues that were addressed at the workshop and identifies areas for future investigation.
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Affiliation(s)
- Anthony W Purcell
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Salvatore Sechi
- Division of Diabetes, Endocrinology, and Metabolic Diseases, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD
| | - Teresa P DiLorenzo
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY
- Division of Endocrinology, Department of Medicine, Albert Einstein College of Medicine, Bronx, NY
- Einstein-Mount Sinai Diabetes Research Center, Albert Einstein College of Medicine, Bronx, NY
- Fleischer Institute for Diabetes and Metabolism, Albert Einstein College of Medicine, Bronx, NY
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10
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Yi L, Swensen AC, Qian WJ. Serum biomarkers for diagnosis and prediction of type 1 diabetes. Transl Res 2018; 201:13-25. [PMID: 30144424 PMCID: PMC6177288 DOI: 10.1016/j.trsl.2018.07.009] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 07/02/2018] [Accepted: 07/24/2018] [Indexed: 12/25/2022]
Abstract
Type 1 diabetes (T1D) culminates in the autoimmune destruction of the pancreatic βcells, leading to insufficient production of insulin and development of hyperglycemia. Serum biomarkers including a combination of glucose, glycated molecules, C-peptide, and autoantibodies have been well established for the diagnosis of T1D. However, these molecules often mark a late stage of the disease when ∼90% of the pancreatic insulin-producing β-cells have already been lost. With the prevalence of T1D increasing worldwide and because of the physical and psychological burden induced by this disease, there is a great need for prognostic biomarkers to predict T1D development or progression. This would allow us to identify individuals at high risk for early prevention and intervention. Therefore, considerable efforts have been dedicated to the understanding of disease etiology and the discovery of novel biomarkers in the last few decades. The advent of high-throughput and sensitive "-omics" technologies for the study of proteins, nucleic acids, and metabolites have allowed large scale profiling of protein expression and gene changes in T1D patients relative to disease-free controls. In this review, we briefly discuss the classical diagnostic biomarkers of T1D but mainly focus on the novel biomarkers that are identified as markers of β-cell destruction and screened with the use of state-of-the-art "-omics" technologies.
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Affiliation(s)
- Lian Yi
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, Washington
| | - Adam C Swensen
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, Washington
| | - Wei-Jun Qian
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, Washington.
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11
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Erharuyi O, Simanski S, McEnaney PJ, Kodadek T. Screening one bead one compound libraries against serum using a flow cytometer: Determination of the minimum antibody concentration required for ligand discovery. Bioorg Med Chem Lett 2018; 28:2773-2778. [PMID: 29395976 PMCID: PMC6064678 DOI: 10.1016/j.bmcl.2018.01.033] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Revised: 01/17/2018] [Accepted: 01/18/2018] [Indexed: 10/18/2022]
Abstract
One bead one compound (OBOC) libraries can be screened against serum samples to identify ligands to antibodies in this mixture. In this protocol, hit beads are identified by staining with a fluorescent labeled secondary antibody. When screens are conducted against two different sets of serum, antibodies, and ligands to them, can be discovered that distinguish the two populations. The application of DNA-encoding technology to OBOC libraries has allowed the use of 10 µm beads for library preparation and screening, which pass through a standard flow cytometer, allowing the fluorescent hit beads to be separated from beads displaying non-ligands easily. An important issue in using this approach for the discovery of antibody biomarkers is its analytical sensitivity. In other words, how abundant must an IgG be to allow it to be pulled out of serum in an unbiased screen using a flow cytometer? We report here a model study in which monoclonal antibodies with known ligands of varying affinities are doped into serum. We find that for antibody ligands typical of what one isolates from an unbiased combinatorial library, the target antibody must be present at 10-50 nM. True antigens, which bind with significantly higher affinity, can detect much less abundant serum antibodies.
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Affiliation(s)
- Osayemwenre Erharuyi
- Department of Chemistry, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458, USA
| | - Scott Simanski
- Department of Chemistry, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458, USA
| | - Patrick J McEnaney
- Department of Chemistry, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458, USA
| | - Thomas Kodadek
- Department of Chemistry, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458, USA.
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12
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Crèvecoeur I, Vig S, Mathieu C, Overbergh L. Understanding type 1 diabetes through proteomics. Expert Rev Proteomics 2017. [DOI: 10.1080/14789450.2017.1345633] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Inne Crèvecoeur
- Laboratory for Clinical and Experimental Endocrinology, KU Leuven, Leuven, Belgium
| | - Saurabh Vig
- Laboratory for Clinical and Experimental Endocrinology, KU Leuven, Leuven, Belgium
| | - Chantal Mathieu
- Laboratory for Clinical and Experimental Endocrinology, KU Leuven, Leuven, Belgium
| | - Lut Overbergh
- Laboratory for Clinical and Experimental Endocrinology, KU Leuven, Leuven, Belgium
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13
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Mendes KR, Malone ML, Ndungu JM, Suponitsky-Kroyter I, Cavett VJ, McEnaney PJ, MacConnell AB, Doran TM, Ronacher K, Stanley K, Utset O, Walzl G, Paegel BM, Kodadek T. High-throughput Identification of DNA-Encoded IgG Ligands that Distinguish Active and Latent Mycobacterium tuberculosis Infections. ACS Chem Biol 2017; 12:234-243. [PMID: 27957856 DOI: 10.1021/acschembio.6b00855] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The circulating antibody repertoire encodes a patient's health status and pathogen exposure history, but identifying antibodies with diagnostic potential usually requires knowledge of the antigen(s). We previously circumvented this problem by screening libraries of bead-displayed small molecules against case and control serum samples to discover "epitope surrogates" (ligands of IgGs enriched in the case sample). Here, we describe an improved version of this technology that employs DNA-encoded libraries and high-throughput FACS-based screening to discover epitope surrogates that differentiate noninfectious/latent (LTB) patients from infectious/active TB (ATB) patients, which is imperative for proper treatment selection and antibiotic stewardship. Normal control/LTB (10 patients each, NCL) and ATB (10 patients) serum pools were screened against a library (5 × 106 beads, 448 000 unique compounds) using fluorescent antihuman IgG to label hit compound beads for FACS. Deep sequencing decoded all hit structures and each hit's occurrence frequencies. ATB hits were pruned of NCL hits and prioritized for resynthesis based on occurrence and homology. Several structurally homologous families were identified and 16/21 resynthesized representative hits validated as selective ligands of ATB serum IgGs (p < 0.005). The native secreted TB protein Ag85B (though not the E. coli recombinant form) competed with one of the validated ligands for binding to antibodies, suggesting that it mimics a native Ag85B epitope. The use of DNA-encoded libraries and FACS-based screening in epitope surrogate discovery reveals thousands of potential hit structures. Distilling this list down to several consensus chemical structures yielded a diagnostic panel for ATB composed of thermally stable and economically produced small molecule ligands in place of protein antigens.
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Affiliation(s)
- Kimberly R. Mendes
- Opko Health, Inc., 5353 Parkside
Drive Jupiter, Florida 33458, United States
| | | | - John Maina Ndungu
- Opko Health, Inc., 5353 Parkside
Drive Jupiter, Florida 33458, United States
| | | | | | | | | | | | - Katharina Ronacher
- Department
of Science and Technology/National Research Foundation Centre of Excellence
for Biomedical TB Research/Medical Research Council Centre for Molecular
and Cellular Biology, Division of Molecular Biology and Human Genetics,
Faculty of Medicine and Health Sciences, Stellenbosch University, Tygerberg, South Africa
| | - Kim Stanley
- Department
of Science and Technology/National Research Foundation Centre of Excellence
for Biomedical TB Research/Medical Research Council Centre for Molecular
and Cellular Biology, Division of Molecular Biology and Human Genetics,
Faculty of Medicine and Health Sciences, Stellenbosch University, Tygerberg, South Africa
| | - Ofelia Utset
- Opko Health, Inc., 5353 Parkside
Drive Jupiter, Florida 33458, United States
| | - Gerhard Walzl
- Department
of Science and Technology/National Research Foundation Centre of Excellence
for Biomedical TB Research/Medical Research Council Centre for Molecular
and Cellular Biology, Division of Molecular Biology and Human Genetics,
Faculty of Medicine and Health Sciences, Stellenbosch University, Tygerberg, South Africa
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