In vitro and in vivo evaluation of cysteine and site specific conjugated herceptin antibody-drug conjugates.

Antibody drug conjugates (ADCs) are monoclonal antibodies designed to deliver a cytotoxic drug selectively to antigen expressing cells. Several components of an ADC including the selection of the antibody, the linker, the cytotoxic drug payload and the site of attachment used to attach the drug to the antibody are critical to the activity and development of the ADC. The cytotoxic drugs or payloads used to make ADCs are typically conjugated to the antibody through cysteine or lysine residues.

Discovery of a human peptide sequence signaling islet neogenesis.

Objective: To identify triggers for islet neogenesis in humans that may lead to new treatments that address the underlying mechanism of disease for patients with type 1 or type 2 diabetes.

Methods: In an effort to identify bioactive human peptide sequences that might trigger islet neogenesis, we evaluated amino acid sequences within a variety of mammalian pancreas-specific REG genes. We evaluated GenBank, the Basic Local Alignment Search Tool algorithm, and all available proteomic databases and developed large-scale protein-to-protein interaction maps.

High-throughput protein concentration and buffer exchange: comparison of ultrafiltration and ammonium sulfate precipitation.

High-throughput protein purification is a complex, multi-step process. There are several technical challenges in the course of this process that are not experienced when purifying a single protein. Among the most challenging are the high-throughput protein concentration and buffer exchange, which are not only labor-intensive but can also result in significant losses of purified proteins.

Automated 96-well purification of hexahistidine-tagged recombinant proteins on MagneHis Ni(2)+-particles.

Functional genomics and the application of high-throughput (HT) approaches to solve biological and medical questions are the main drivers behind the increasing need for HT parallel expression and purification of recombinant proteins. Automation is necessary to facilitate this complex multistep process. We describe, in detail, an HT-automated purification of hexahistidine-tagged recombinant proteins using MagneHis Ni-Particles and the Biomek FX robot.

Statistically inferring protein-protein associations with affinity isolation LC-MS/MS assays.

Affinity isolation of protein complexes followed by protein identification by LC-MS/MS is an increasingly popular approach for mapping protein interactions. However, systematic and random assay errors from multiple sources must be considered to confidently infer authentic protein-protein interactions. To address this issue, we developed a general, robust statistical method for inferring authentic interactions from protein prey-by-bait frequency tables using a binomial-based likelihood ratio test (LRT) coupled with Bayes' Odds estimation.