Mabselect sure beads

All animal work in this study was performed in a facility accredited by Association for Assessment and Accreditation of Laboratory Animal Care International (AAALAC International). All protocols were approved by the Rinat Institutional Animal Care and Use Committee (IACUC). All procedures were performed under isoflurane anesthesia, and all efforts were taken to minimize suffering. Our facility complies with the Guide For The Care and Use of Laboratory Animals (Eight Edition). Compounds were dosed IV into 9 weeks old female CB17 SCID mice (The Jackson Laboratory) in 3 groups (n = 9) through the lateral tail vein at 10 mg/kg. Plasma samples were obtained under anesthesia at terminal bleeds 4.5 days following injection. Samples were pooled, diluted with an equal volume of 1x PBS pH 7.4, and conjugates were isolated using MabSelect SuRe beads or M1S1 antigen coupled to CNBr-activated Sepharose (GE Healthcare, Inc.) following standard protocols. DAR values were assessed using HIC or mass spectrometric methods.

Plasma samples from mouse, rat, cynomolgus monkey and human were purchased from BioreclamationIVT. In vitro stability assays were carried out by incubating 0.125 mg/mL of ADC in 62.5% (v/v) plasma diluted in 1x PBS. Protease inhibitors (Roche, Sigma) were added to plasma at appropriate concentrations as needed. In some assays, pH was adjusted by addition of 120 mM potassium phosphate pH 7.4. Following incubation at 37°C for 3–4.5 days, samples were diluted with an equal volume of 1x PBS, and conjugates were isolated using MabSelect SuRe beads or M1S1 antigen coupled to CNBr-activated Sepharose (GE Healthcare, Inc.) following standard protocols. DAR values were assessed using HIC or mass spectrometric methods. All reported values are averages of three independent measurements.