A CD22-specific T-cell receptor enables effective adoptive T-cell therapy for B-cell malignancies

S Simone Rhein (1Department of Hematology, Oncology and Cancer Immunology, Campus Benjamin Franklin, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany) N Neşe Çakmak-Görür (1Department of Hematology, Oncology and Cancer Immunology, Campus Benjamin Franklin, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany) C Corinna Grunert (1Department of Hematology, Oncology and Cancer Immunology, Campus Benjamin Franklin, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany) S Sarah Al-Tabatabaee (1Department of Hematology, Oncology and Cancer Immunology, Campus Benjamin Franklin, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany) N Nazli Serin (Department of Hematology, Oncology and Tumor Immunology, Charité University Medical Center) M Matthias Leisegang (5Institute of Tumor Immunology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany) S Stefanos Timiliotis (1Department of Hematology, Oncology and Cancer Immunology, Campus Benjamin Franklin, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany) L Luisa Ohlmeier (1Department of Hematology, Oncology and Cancer Immunology, Campus Benjamin Franklin, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany) C Cäcilia Freund (1Department of Hematology, Oncology and Cancer Immunology, Campus Benjamin Franklin, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany) G Gerald Willimsky F Frank Konietschke E Elisa Kieback (9T-Knife Therapeutics GmbH, Berlin, Germany) S Sarah K. Tasian B Björn Chapuy (Department of Hematology, Oncology and Tumor Immunology, Charité University Medical Center) U Ulrich Keller T Thomas Blankenstein A Antonio Pezzutto (1Department of Hematology, Oncology and Cancer Immunology, Campus Benjamin Franklin, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany) A Antonia Busse

Abstract

Abstract CD19 chimeric antigen receptor (CAR) T-cell therapy has become the standard of care in relapse and/or refractory B-cell malignancies. Up to 30% to 60% of patients experience relapsed disease because of the emergence of CD19low or CD19− tumor cell clones. Although bispecific CD19/CD22 CAR T cells have been explored, limited persistence and antigen downregulation of CD19 and/or CD22 have compromised their efficacy in relapsing patients. A comprehensive analysis of CD22 expression revealed that CD22 is ubiquitously expressed across all subgroups of B-cell lymphomas and B-cell leukemias, establishing CD22 as a valuable immunotherapeutic target. Using a humanized mouse model with a diverse human T-cell receptor (TCR) repertoire, we identified a high-affinity TCR targeting a CD22 epitope presented by HLA-A∗02:01. In vitro, this TCR demonstrated high specificity and efficacy in both CD22+ cell lines and primary patient-derived tumor samples. Importantly, CD22 TCR T cells outperformed CD22 CAR T cells in recognizing cells with low CD22 surface expression, including CD22low Nalm6 cells that emerged after in vivo CD19 T-cell treatment. Unlike CD22 CAR T cells, CD22 TCR T cells effectively recognized tumor cells that predominantly express intracellular CD22. Notably, in vivo validation in a Nalm6 B-cell leukemia model confirmed the superior activity of CD22 TCR T cells against CD22low cells compared to CD22 CAR T cells. In conclusion, our findings provide strong preclinical evidence supporting CD22 TCR-based therapy as a potent treatment option for CD22low B-cell malignancies, including patients who relapsed after CD19 CAR T-cell therapy.

Article Details

Journal Blood
Volume / Issue Vol. 147, Issue 10
Published March 05, 2026
Pages 1058-1069
ISSN 0006-4971
Publisher Elsevier BV

Journal Info

Blood

Elsevier BV

ISSN: 0006-4971 Health Sciences

Authors (18)

S

Simone Rhein

1Department of Hematology, Oncology and Cancer Immunology, Campus Benjamin Franklin, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany

N

Neşe Çakmak-Görür

1Department of Hematology, Oncology and Cancer Immunology, Campus Benjamin Franklin, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany

C

Corinna Grunert

1Department of Hematology, Oncology and Cancer Immunology, Campus Benjamin Franklin, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany

S

Sarah Al-Tabatabaee

1Department of Hematology, Oncology and Cancer Immunology, Campus Benjamin Franklin, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany

N

Nazli Serin

Department of Hematology, Oncology and Tumor Immunology, Charité University Medical Center

M

Matthias Leisegang

5Institute of Tumor Immunology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany

S

Stefanos Timiliotis

1Department of Hematology, Oncology and Cancer Immunology, Campus Benjamin Franklin, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany

L

Luisa Ohlmeier

1Department of Hematology, Oncology and Cancer Immunology, Campus Benjamin Franklin, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany

C

Cäcilia Freund

1Department of Hematology, Oncology and Cancer Immunology, Campus Benjamin Franklin, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany

G

Gerald Willimsky

F

Frank Konietschke

E

Elisa Kieback

9T-Knife Therapeutics GmbH, Berlin, Germany

S

Sarah K. Tasian

B

Björn Chapuy

Department of Hematology, Oncology and Tumor Immunology, Charité University Medical Center

U

Ulrich Keller

T

Thomas Blankenstein

A

Antonio Pezzutto

1Department of Hematology, Oncology and Cancer Immunology, Campus Benjamin Franklin, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany

A

Antonia Busse