Nature of Guanine Oxidation in RNA via the Flash-Quench Technique versus Direct Oxidation by a Metal Oxo Complex

Oxidation of RNA can be effected by two different techniques: a photochemical, electron-transfer method termed “flash-quench” and direct oxidation by metal oxo complexes. The flash-quench method produces selective oxidation using a metal photosensitizer, tris(bipyridyl)ruthenium(III) trichloride (Ru(bpy)33+), and quencher, pentaamminechlorocobalt(III) chloride (Co(NH3)5Cl2+). We have optimized the flash-quench technique for the following RNAs: tRNAPhe, human ferritin iron-responsive element (IRE), and a mutated human ferritin IRE. We have also employed a chemical footprinting technique involving the oxoruthenium(IV) complex (Ru(tpy)(bpy)O2+ (tpy = 2,2′,2″-terpyridine; bpy = 2,2′-bipyridine)) to oxidize guanine. Comparison of the two methods shows that the flash-quench technique provides a visualization of nucleotide accessibility for a static conformation of RNA while the Ru(tpy)(bpy)O2+ complex selectively oxidizes labile guanines and gives a visualization of a composite of multiple conformations of the RNA structure

Microfabricated Particles for Engineered Drug Therapies: Elucidation into the Mechanisms of Cellular Internalization of PRINT Particles

To investigate the cellular internalization pathways of shape- and size-specific particles as a function of zeta potential in different cell types

A Novel HLA-A*0201 Restricted Peptide Derived from Cathepsin G Is an Effective Immunotherapeutic Target in Acute Myeloid Leukemia

Immunotherapy targeting aberrantly expressed leukemia associated antigens (LAA) has shown promise in the management of acute myeloid leukemia (AML). However, because of the heterogeneity and clonal evolution that is a feature of myeloid leukemia, targeting single peptide epitopes has had limited success, highlighting the need for novel antigen discovery. In this study, we characterize the role of the myeloid azurophil granule protease cathepsin G (CG) as a novel target for AML immunotherapy

Peptide/MHC Tetramer-Based Sorting of CD8+ T Cells to a Leukemia Antigen Yields Clonotypes Drawn Nonspecifically from an Underlying Restricted Repertoire

Testing of T cell-based cancer therapeutics often involves measuring cancer antigen-specific T-cell populations with the assumption that they arise from in vivo clonal expansion. This analysis, using peptide/MHC tetramers, is often ambiguous