Influenza A continues to be a serious public health threat as it continuously evolves to evade and escape immune surveillance through genetic drift, shift, and re-assortment. Hemagglutinin (HA) is the main glycoprotein target of the humoral immune response and elicits protective, neutralizing, antibodies during infection. However, these antibodies are usually specific for the influenza subtype causing infection and exhibit a narrow spectrum of protectiveness. To date, many of the influenza-neutralizing monoclonal antibodies described are cross-specific for subtypes H1 and H5 but do not neutralize subtypes H3 or H7. Therefore, we have designed an approach to survey the human B cell repertoire to identify monoclonal antibodies that neutralize influenza viruses of both the H1 and H3 subtypes. Our strategy is to identify humans that have broadly reactive serum antibodies, culture IgG+ memory B cells from these individuals at near clonal density, and then assay the culture supernatants for the presence of antibodies that neutralize both H1 and H3 influenza subtypes. By combining functional and binding assays we will determine if there exist in nature highly conserved neutralizing epitopes that are represented on most or all of the influenza HA subtypes tested.
A serum titer of autoantibodies to IFN-α has been reported in several autoimmune conditions and in many cases has been shown to neutralize IFN-α. The IFN-α antibody repertoire from 10 patients with autoimmune myasthenia gravis and associated thymoma (MG/T) was characterized. Surface IgG positive memory B-cells from peripheral blood mononuclear cells (PBMC) were cultured in 384-well plates to produce assayable quantities of antibody. Sensitive antibody microarray and AlphaScreen™ binding assays were used to identify antibodies reactive with IFN-α(2a). A range of IFN-α subtype specificity profiles was observed in competition assays for binding to the 12 subtypes of IFN-α. A subset of these antibodies was expressed recombinantly after recovery of heavy and light chain variable regions by RT-PCR and these recombinant antibodies recapitulated the activities demonstrated in the B-cell culture supernatants. These antibodies fell into 2 groups, blocking binding of IFN-α(2a) to either the IFNAR2 or IFNAR1 subunit of the Type 1 interferon receptor. The ability of these antibodies to neutralize the activity of IFN-α(2a) in a Daudi cell proliferation assay was confirmed. The antibody repertoires of MG/T patients include high affinity antibodies with both broad and narrow specificities for the different subtypes of IFN-α. These function-blocking human antibodies may have therapeutic utility in IFN-α dependent diseases such as SLE.
Unlike HER2-positive breast cancer, there are limited treatment options for patients diagnosed with triple negative and endocrine resistant HER2-negative breast cancer, and as such HER2-negative breast cancer represents a significant unmet medical need. The goal of this work is to use Theraclone’s proprietary I-STAR platform to mine the memory B cell immune repertoire of breast cancer patients for the discovery of therapeutically relevant monoclonal antibodies (mAbs) and targets that may be exploited as candidates for treatment of HER2-negative breast cancer. Matched serum and PBMC samples were collected from breast cancer patients at multiple clinical sites. The selected patient populations included, but were not limited to, patients who were treatment naïve, those who had received immunotherapy or adjuvant chemotherapy, and patients who had an exceptional clinical response to treatment and/or disease. Serum antibody binding to a diverse panel of 5 well characterized breast cancer-derived cell lines of luminal and basal sub-types was determined. Utilizing this approach, patients with a robust serological profile across multiple breast cancer cell lines were identified and prioritized for memory B cell repertoire analysis via the I-STAR platform. Using a high throughput and miniaturized, multiplex flow cytometry assay, the secreted IgG antibodies from over 85,000 individually enriched and expanded B cell clones were screened for binding to the tumor cell line panel and a large number of positive B cell clones were identified. The screening hits can be binned into several unique binding profiles, many of which were confirmed to be shared across multiple patient samples. Deep sequence analysis of the variable regions of the antibodies produced by the B cell clones demonstrated that several of the screening hits were derived from clonally related B cells; the majority of the screening hits represented antibodies derived from unique B cell clones. A representative set of these antibodies was expressed recombinantly for further in vitro characterization. Citation Format: Christy Boozer, Paul Algate, Aurelio Bonavia, Mark Branum, Po-Ying Chan-Hui, Alison Fitch, Brad Greenfield, Claire Sutherland, Kristine Swiderek. Discovery of fully human monoclonal antibodies as therapeutic candidates for the treatment of HER2-negative breast cancer [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P2-16-01.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.