The use of T-cell engagers (TCEs) to treat solid tumors is challenging, and several have been limited by narrow therapeutic windows due to substantial on-target, off-tumor toxicities due to the expression of low levels of target antigens on healthy tissues. Here, we describe TNB-928B, a fully human TCE that has a bivalent binding arm for folate receptor alpha (FRα) to selectively target FRα overexpressing tumor cells while avoiding the lysis of cells with low levels of FRα expression. The bivalent design of the FRα binding arm confers tumor selectivity due to low-affinity but high-avidity binding to high FRα antigen density cells.
View Article and Find Full Text PDFThe use of recombinant interleukin-2 (IL-2) as a therapeutic protein has been limited by significant toxicities despite its demonstrated ability to induce durable tumor-regression in cancer patients. The adverse events and limited efficacy of IL-2 treatment are due to the preferential binding of IL-2 to cells that express the high-affinity, trimeric receptor, IL-2Rαβγ such as endothelial cells and T-regulatory cells, respectively. Here, we describe a novel bispecific heavy-chain only antibody which binds to and activates signaling through the heterodimeric IL-2Rβγ receptor complex that is expressed on resting T-cells and NK cells.
View Article and Find Full Text PDFThe therapeutic potential of targeting CD19 in B cell malignancies has garnered attention in the past decade, resulting in the introduction of novel immunotherapy agents. Encouraging clinical data have been reported for T cell-based targeting agents, such as anti-CD19/CD3 bispecific T-cell engager blinatumomab and chimeric antigen receptor (CAR)-T therapies, for acute lymphoblastic leukemia and B cell non-Hodgkin lymphoma (B-NHL). However, clinical use of both blinatumomab and CAR-T therapies has been limited due to unfavorable pharmacokinetics (PK), significant toxicity associated with cytokine release syndrome and neurotoxicity, and manufacturing challenges.
View Article and Find Full Text PDFDespite the similar enzyme cascade in the Ubiquitin and Ubiquitin-like peptide(Ubl) conjugation, the involvement of single or heterodimer E1 activating enzyme has been a mystery. Here, by using a quantitative Förster Resonance Energy Transfer (FRET) technology, aided with Analysis of Electrostatic Similarities Of Proteins (AESOP) computational framework, we elucidate in detail the functional properties of each subunit of the E1 heterodimer activating-enzyme for NEDD8, UBA3 and APPBP1. In contrast to SUMO activation, which requires both subunits of its E1 heterodimer AOS1-Uba2 for its activation, NEDD8 activation requires only one of two E1 subunits, UBA3.
View Article and Find Full Text PDFFörster resonance energy transfer (FRET) technology has been widely used in biological and biomedical research and is a valuable tool for elucidating molecular interactions in vitro and in vivo. Quantitative FRET analysis is a powerful method for determining biochemical parameters and molecular distances at nanometer levels. Recently, we reported theoretical developments and experimental procedures for determining the dissociation constant, Kd and enzymatic kinetics parameters, Kcat and KM, of protein interactions with the engineered FRET pair, CyPet and YPet.
View Article and Find Full Text PDFAnnu Int Conf IEEE Eng Med Biol Soc
September 2013
Rapid detection and identification of endospores presents a range of complex challenges. Dynamic staining approach, developed in our lab, utilizes the time-course fluorescence enhancement of an amyloid-staining dye, Thioflavin T (ThT), after mixing with intact endospores. We examined the kinetics of staining Bacillus atrophaeus and Bacillus thuringiensis endospores, and the rates of staining were different for the two bacilli when intact endospores were treated with ThT.
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