SMARTer Human TCR a/b Profiling Kit v2—flexible kit with ultimate sensitivity for understanding the TCR repertoire

Figure 1. Sensitive and reproducible clonotype detection from a broad range of RNA amounts. TRA and TRB libraries were generated from 1, 10, and 100 ng of human CD3+ T-cell total RNA and 1,000 and 10,000 CD3+ T cells. The sequence reads were processed by the Cogent NGS Immune Profiler Software.

Table 1. Assessing the sensitivity and reproducibility of the SMARTer approach. Spike-in analysis was performed in replicate on PBMC RNA samples spiked at varying concentrations (10%, 1%, 0.1%, 0.01%, 0.001%, and 0.0001%) with RNA obtained from a homogeneous population of leukemic Jurkat T cells (containing TRBV12-3-TRBJ1-2 clonotypes). TRB CDR3 regions were amplified from 100 ng of total RNA using the TCRv2 kit and sequenced. Reads of 2 x 150 bp were obtained on an Illumina NextSeq® system. The sequencing reads were downsampled to 2.5 M reads. Read results for spike-in concentrations identified as the reliable concentration limit for each criterion (without and with UMI collapse) have data highlighted in gray. Without UMI collapse, PCR duplicates of TRBV12-3 were observed in 0.0010% of the raw reads.

Figure 2. Superior sensitivity and reproducibility with TCRv2. We split 5M PBMC cells from two different healthy donors for RNA and gDNA extraction. 1.6 µg of gDNA was used for library preparation according to the manufacturer's instructions (15% of the total amount of extracted gDNA). 100 ng of RNA was used for library preparation (2% of the total amount of extracted RNA). Clonotype numbers for TCRa/b libraries are shown from each company (NT: not tested). In the comparison, TCRv2 generated an average of 48.7K and 163K clonotypes for TRA and TRB, respectively, representing a 290% increase against Company Q's RNA-based approach and a 145% increase against Company A's gDNA-based approach. Importantly, the RNA methods used only 2% of the total RNA from the 5M PBMCs.