TY  - JOUR
A1  - Rydzek, Julian
A1  - Nerreter, Thomas
A1  - Peng, Haiyong
A1  - Jutz, Sabrina
A1  - Leitner, Judith
A1  - Steinberger, Peter
A1  - Einsele, Hermann
A1  - Rader, Christoph
A1  - Hudecek, Michael
T1  - Chimeric Antigen Receptor Library Screening Using a Novel NF-kappa B/NFAT Reporter Cell Platform
JF  - Molecular Therapy
N2  - Chimeric antigen receptor (CAR)-T cell immunotherapy is under intense preclinical and clinical investigation, and it involves a rapidly increasing portfolio of novel target antigens and CAR designs. We established a platform that enables rapid and high-throughput CAR-screening campaigns with reporter cells derived from the T cell lymphoma line Jurkat. Reporter cells were equipped with nuclear factor kappa B (NF kappa B) and nuclear factor of activated T cells (NFAT) reporter genes that generate a duplex output of enhanced CFP (ECFP) and EGFP, respectively. As a proof of concept, we modified reporter cells with CD19-specific and ROR1-specific CARs, and we detected high-level reporter signals that allowed distinguishing functional from non-functional CAR constructs. The reporter data were highly reproducible, and the time required for completing each testing campaign was substantially shorter with reporter cells (6 days) compared to primary CAR-T cells (21 days). We challenged the reporter platform to a large-scale screening campaign on a ROR1-CAR library, and we showed that reporter cells retrieved a functional CAR variant that was present with a frequency of only 6 in 1.05 x 10(6). The data illustrate the potential to implement this reporter platform into the preclinical development path of novel CAR-T cell products and to inform and accelerate the selection of lead CAR candidates for clinical translation.
KW  - NF-κB/NFAT reporter cells
KW  - chimeric antigen receptor
KW  - library screening
KW  - cancer immunotherapy
KW  - ROR1
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-227193
VL  - 27
IS  - 2
ER  - 
TY  - JOUR
A1  - Nerreter, Thomas
A1  - Letschert, Sebastian
A1  - Götz, Ralph
A1  - Doose, Sören
A1  - Danhof, Sophia
A1  - Einsele, Hermann
A1  - Sauer, Markus
A1  - Hudecek, Michael
T1  - Super-resolution microscopy reveals ultra-low CD19 expression on myeloma cells that triggers elimination by CD19 CAR-T
JF  - Nature Communications
N2  - Immunotherapy with chimeric antigen receptor-engineered T-cells (CAR-T) is under investigation in multiple myeloma. There are reports of myeloma remission after CD19 CAR-T therapy, although CD19 is hardly detectable on myeloma cells by flow cytometry (FC). We apply single molecule-sensitive direct stochastic optical reconstruction microscopy (dSTORM), and demonstrate CD19 expression on a fraction of myeloma cells (10.3–80%) in 10 out of 14 patients (density: 13–5,000 molecules per cell). In contrast, FC detects CD19 in only 2 of these 10 patients, on a smaller fraction of cells. Treatment with CD19 CAR-T in vitro results in elimination of CD19-positive myeloma cells, including those with <100 CD19 molecules per cell. Similar data are obtained by dSTORM analyses of CD20 expression on myeloma cells and CD20 CAR-T. These data establish a sensitivity threshold for CAR-T and illustrate how super-resolution microscopy can guide patient selection in immunotherapy to exploit ultra-low density antigens.
KW  - cancer imaging
KW  - cancer immunotherapy
KW  - imaging
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-232258
VL  - 10
ER  -