Publications by authors named "Douglas Burtrum"

The CD137 receptor plays a key role in mediating immune response by promoting T cell proliferation, survival, and memory. Effective agonism of CD137 has the potential to reinvigorate potent antitumor immunity either alone or in combination with other immune-checkpoint therapies. In this study, we describe the discovery and characterization of a unique CD137 agonist, 7A5, a fully human IgG1 Fc effector-null monoclonal antibody.

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Unfortunately, after publication of this article [1], it was noticed that corrections to the legends of Figs. 1 and 2 were not correctly incorporated. The correct legends can be seen below.

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Background: Modulation of the PD-1/PD-L1 axis through antagonist antibodies that block either receptor or ligand has been shown to reinvigorate the function of tumor-specific T cells and unleash potent anti-tumor immunity, leading to durable objective responses in a subset of patients across multiple tumor types.

Results: Here we describe the discovery and preclinical characterization of LY3300054, a fully human IgG1λ monoclonal antibody that binds to human PD-L1 with high affinity and inhibits interactions of PD-L1 with its two cognate receptors PD-1 and CD80. The functional activity of LY3300054 on primary human T cells is evaluated using a series of in vitro T cell functional assays and in vivo models using human-immune reconstituted mice.

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Bi-specific antibodies (BsAbs), which can simultaneously block 2 tumor targets, have emerged as promising therapeutic alternatives to combinations of individual monoclonal antibodies. Here, we describe the engineering and development of a novel, human bi-functional antibody-receptor domain fusion molecule with ligand capture (bi-AbCap) through the fusion of the domain 2 of human vascular endothelial growth factor receptor 1 (VEGFR1) to an antibody directed against insulin-like growth factor - type I receptor (IGF-IR). The bi-AbCap possesses excellent stability and developability, and is the result of minimal engineering.

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Stem cell factor receptor (c-Kit) exerts multiple biological effects on target cells upon binding its ligand stem cell factor (SCF). Aberrant activation of c-Kit results in dysregulated signaling and is implicated in the pathogenesis of numerous cancers. The development of more specific and effective c-Kit therapies is warranted given its essential role in tumorigenesis.

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Purpose: To evaluate the antibody-dependent cellular cytotoxicity (ADCC) of cetuximab, an anti-epidermal growth factor receptor (EGFR) IgG1 antibody, in vitro.

Methods: Binding to human Fc receptors was measured by ELISA. ADCC against a panel of tumor cell lines was evaluated using peripheral blood mononuclear cells or NK cells as effectors and lactate dehydrogenase release as a marker of cell killing.

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Purpose: Transforming growth factor beta (TGFbeta) is a pleiotropic cytokine that affects tumor growth, metastasis, stroma, and immune response. We investigated the therapeutic efficacy of anti-TGFbeta receptor II (TGFbeta RII) antibody in controlling metastasis and tumor growth as well as enhancing antitumor immunity in preclinical tumor models.

Experimental Design: We generated neutralizing antibodies to TGFbeta RII and assessed the antibody effects on cancer, stroma, and immune cells in vitro.

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Targeted monoclonal antibody therapy is an important strategy in cancer therapeutics. Among the most promising characteristics of therapeutic targets are those that modulate the growth and survival of malignant neoplasms and their sensitivity to anticancer therapies. The insulin-like growth factor-I receptor (IGF-IR) is overexpressed in many types of solid and hematopoietic malignancies, and has been implicated as a principal cause of heightened proliferative and survival signaling.

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Although many multiple myeloma (MM) patients initially respond to cytotoxic therapy, most eventually relapse. Novel therapeutic strategies employing a combination of chemotherapy with targeted biologics may significantly enhance the response of tumor cells to treatment. We tested a fully human anti-IGF-IR antibody (A12) against MM, and showed specific inhibition of IGF-I or serum-induced IGF-IR signaling in MM cells in vitro.

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Recombinant protein production in plants such as corn is a promising means to generate high product yields at low comparable production cost. The anti-EGFR monoclonal antibody C225, cetuximab, is a well-characterized receptor antagonist antibody recently approved for the treatment of refractory colorectal cancer. We initiated a study to test and compare the functional activity of glycosylated and aglycosylated C225 produced in stable transgenic corn seed.

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The insulin-like growth factor I receptor (IGF-IR) is overexpressed in many diverse tumor types and is a critical signaling molecule for tumor cell proliferation and survival. Therapeutic strategies targeting the IGF-IR may therefore be effective broad-spectrum anticancer agents. Through screening of a Fab phage display library, we have generated a fully human antibody (A12) that binds to the IGF-IR with high affinity (4.

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Both the epidermal growth factor receptor (EGFR) and the insulin-like growth factor receptor (IGFR) have been implicated in the tumorigenesis of a variety of human cancers. Effective tumor inhibition has been achieved both experimentally and clinically with a number of strategies that antagonize either receptor activity. Here we constructed and produced two fully human recombinant bispecific antibodies (BsAb) that target both EGFR and IGFR, using two neutralizing human antibodies originally isolated from a phage display library.

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