A novel TCR-like CAR with specificity for PR1/HLA-A2 effectively targets myeloid leukemia in vitro when expressed in human adult peripheral blood and cord blood T cells

Cytotherapy. 2016 Aug;18(8):985-994. doi: 10.1016/j.jcyt.2016.05.001. Epub 2016 Jun 2.


Background aims: The PR1 peptide, derived from the leukemia-associated antigens proteinase 3 and neutrophil elastase, is overexpressed on HLA-A2 in acute myeloid leukemia (AML). We developed a T-cell receptor (TCR)-like monoclonal antibody (8F4) that binds the PR1/HLA-A2 complex on the surface of AML cells, efficiently killing them in vitro and eliminating them in preclinical models. Humanized 8F4 (h8F4) with high affinity for the PR1/HLA-A2 epitope was used to construct an h8F4- chimeric antigen receptor (CAR) that was transduced into T cells to mediate anti-leukemia activity.

Methods: Human T cells were transduced to express the PR1/HLA-A2-specific CAR (h8F4-CAR-T cells) containing the scFv of h8F4 fused to the intracellular signaling endo-domain of CD3 zeta chain through the transmembrane and intracellular costimulatory domain of CD28.

Results: Adult human normal peripheral blood (PB) T cells were efficiently transduced with the h8F4-CAR construct and predominantly displayed an effector memory phenotype with a minor population (12%) of central memory cells in vitro. Umbilical cord blood (UCB) T cells could also be efficiently transduced with the h8F4-CAR. The PB and UCB-derived h8F4-CAR-T cells specifically recognized the PR1/HLA-A2 complex and were capable of killing leukemia cell lines and primary AML blasts in an HLA-A2-dependent manner.

Conclusions: Human adult PB and UCB-derived T cells expressing a CAR derived from the TCR-like 8F4 antibody rapidly and efficiently kill AML in vitro. Our data could lead to a new treatment paradigm for AML in which targeting leukemia stem cells could transfer long-term immunity to protect against relapse.

Keywords: CAR-T cell; PR1; UCB; acute myeloid leukemia (AML); h8F4.

MeSH terms

  • Adult
  • Antibodies, Monoclonal / immunology
  • Antibodies, Monoclonal / metabolism
  • Cell Line
  • Epitopes / immunology
  • Fetal Blood* / cytology
  • Fetal Blood* / immunology
  • Genetic Therapy
  • HLA-A2 Antigen / immunology*
  • Humans
  • Immunoglobulin Fc Fragments / chemistry
  • Immunoglobulin Fc Fragments / immunology
  • Immunoglobulin Fc Fragments / metabolism
  • Immunotherapy, Adoptive / methods
  • Leukemia, Myeloid, Acute / immunology
  • Leukemia, Myeloid, Acute / pathology
  • Leukemia, Myeloid, Acute / therapy*
  • Leukocytes, Mononuclear / immunology
  • Leukocytes, Mononuclear / metabolism*
  • Myeloblastin / chemistry
  • Myeloblastin / immunology*
  • Peptide Fragments / chemistry
  • Peptide Fragments / immunology
  • Receptors, Antigen, T-Cell / genetics
  • Receptors, Antigen, T-Cell / immunology
  • Receptors, Antigen, T-Cell / metabolism*
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / immunology
  • Recombinant Fusion Proteins / metabolism
  • T-Cell Antigen Receptor Specificity
  • T-Lymphocytes / immunology
  • T-Lymphocytes / metabolism*


  • Antibodies, Monoclonal
  • Epitopes
  • HLA-A2 Antigen
  • Immunoglobulin Fc Fragments
  • Peptide Fragments
  • Receptors, Antigen, T-Cell
  • Recombinant Fusion Proteins
  • Myeloblastin