The Oncomine TCR Beta-LR Assay is designed to measure T cell diversity and clonal expansion by sequencing T cell receptor beta chain rearrangements. This assay utilizes a newly developed long-read sequencing technology on the Ion GeneStudio S5 next-generation sequencing systems. The assay kit provides a single pool of multiplex PCR primers, library reagents, and sample barcodes. Ion AmpliSeq libraries can be generated from research samples such as RNA extracted from whole blood, fresh-frozen tissue, or FACS-sorted cells.