High throughput development of TCR-mimic antibody that targets survivin-2B80-88/HLA-A*A24 and its application in a bispecific T-cell engager

Abstract

Intracellular tumor-associated antigens are targeted by antibodies known as T-cell receptor mimic antibodies (TCRm-Abs), which recognize T-cell epitopes with better stabilities and higher affinities than T-cell receptors. However, TCRm-Abs have been proven difficult to produce using conventional techniques. Here, we developed TCRm-Abs that recognize the survivin-2B-derived nonamer peptide, AYACNTSTL (SV2B 80-88 ), presented on HLA-A*24 (SV2B 80-88 /HLA-A*24) from immunized mice by using a fluorescence-activated cell sorting-based antigen-specific plasma cells isolation method combined with a high-throughput single-cell-based immunoglobulin-gene-cloning technology. This approach yielded a remarkable efficiency in generating candidate antibody clones that recognize SV2B 80-88 /HLA-A*24. The screening of the antibody clones for their affinity and ability to bind key amino-acid residues within the target peptide revealed that one clone, #21-3, specifically recognized SV2B 80-88 /HLA-A*24 on T2 cells. The specificity of #21-3 was further established through survivin-2B-positive tumor cell lines that exogenously or endogenously express HLA-A*24. A bispecific T-cell engager comprised of #21-3 and anti-CD3 showed specific cytotoxicity towards cells bearing SV2B 80-88 /HLA-A*24 by recruiting and activating T-cells in vitro . The efficient development of TCRm-Ab overcomes the limitations that hamper antibody-based immunotherapeutic approaches and enables the targeting of intracellular tumor-associated antigens.

Development of a T‐cell receptor mimic antibody targeting a novel Wilms tumor 1‐derived peptide and analysis of its specificity

“…The ability of the TCRm‐Ab to bind to cells was assessed by FACS according to a previously described method 27 . Briefly, cells were labeled with 1 µg/mL #25‐8 for 30‐60 minutes at 4°C and then stained with a goat anti–mouse IgG (H + L) DyLight 650 antibody (Thermo Fisher Scientific) for 30 minutes at 4°C.…”

“…We recently reported a FACS‐based strategy combined with a single‐cell immunoglobulin heavy chain variable (VH) and light chain variable (VL) gene cloning method for efficient development of TCRm‐Abs targeting a Survivin 2B‐derived peptide loaded on HLA‐A*24 27 . By using this approach, we generated antibody clones recognizing WT1C loaded on HLA‐A*02:01 (WT1C/HLA‐A*02).…”

Cancer therapeutics using survivin BIRC5 as a target: what can we do after over two decades of study?

“…Here, we should mention that survivin peptide immunogen-reactive antibodies should be considered as an additional advantage for survivin immunotherapy. The potential of this concept has been recently demonstrated in a couple of studies explored from different angles [164,165].…”

Overcoming Challenges for CD3-Bispecific Antibody Therapy in Solid Tumors

“…Furthermore, this table also includes CD3-BsAb formats based on affinity-enhanced TCR-like domains that recognize peptide–human leukocyte antigen (HLA) complexes (immune mobilizing monoclonal T-cell receptors against cancer (ImmTACs)) [ 42 ]. Multiple other TAAs are currently pursued in preclinical studies hoping to make their way to the clinic, including B7-H4, CD133, CD155, claudin 6 (CLDN6), cellular mesenchymal to epithelial transcription factor (C-MET), ephrin receptor A10 (EphA10), folate receptor 1 (FOLR1), HLA-A*24:survivin 2B 80-88 , integrin β4 (ITGB4), P-cadherin, prolactin receptor (PRLR), receptor tyrosine kinase-like orphan receptor 1 (ROR1), TNF-related apoptosis-inducing ligand receptor (TRAIL-R2), transferrin receptor (TfR) and tumor-associated calcium signal transducer 2 (Trop-2) [ 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 ].…”