Peptide/MHC tetramer-based sorting of CD8⁺ T cells to a leukemia antigen yields clonotypes drawn nonspecifically from an underlying restricted repertoire.

Journal Article

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. From a leukemia cell line, we identified a CDK4-derived peptide epitope, UNC-CDK4-1 (ALTPVVVTL), that bound HLA-A*02:01 with high affinity and could induce CD8⁺ T-cell responses in vitro. We identified UNC-CDK4-1/HLA-A*02:01 tetramer⁺ populations in 3 of 6 patients with acute myeloid leukemia who had undergone allogeneic stem cell transplantation. Using tetramer-based, single-cell sorting and T-cell receptor β (TCRβ) sequencing, we identified recurrent UNC-CDK4-1 tetramer-associated TCRβ clonotypes in a patient with a UNC-CDK4-1 tetramer⁺ population, suggesting in vivo T-cell expansion to UNC-CDK4-1. In parallel, we measured the patient's TCRβ repertoire and found it to be highly restricted/oligoclonal. The UNC-CDK4-1 tetramer-associated TCRβ clonotypes represented >17% of the entire TCRβ repertoire-far in excess of the UNC-CDK4-1 tetramer⁺ frequency-indicating that the recurrent TCRβ clonotypes identified from UNC-CDK-4-1 tetramer⁺ cells were likely a consequence of the extremely constrained T-cell repertoire in the patient and not in vivo UNC-CDK4-1-driven clonal T-cell expansion. Mapping recurrent TCRβ clonotype sequences onto TCRβ repertoires can help confirm or refute antigen-specific T-cell expansion in vivo.

Full Text

Duke Authors

Cited Authors

  • Hunsucker, SA; McGary, CS; Vincent, BG; Enyenihi, AA; Waugh, JP; McKinnon, KP; Bixby, LM; Ropp, PA; Coghill, JM; Wood, WA; Gabriel, DA; Sarantopoulos, S; Shea, TC; Serody, JS; Alatrash, G; Rodriguez-Cruz, T; Lizée, G; Buntzman, AS; Frelinger, JA; Glish, GL; Armistead, PM

Published Date

  • March 2015

Published In

Volume / Issue

  • 3 / 3

Start / End Page

  • 228 - 235

PubMed ID

  • 25576336

Electronic International Standard Serial Number (EISSN)

  • 2326-6074

International Standard Serial Number (ISSN)

  • 2326-6066

Digital Object Identifier (DOI)

  • 10.1158/2326-6066.cir-14-0001

Language

  • eng