Efficient elimination of primary B-ALL cells in vitro and in vivo using a novel 4-1BB-based CAR targeting a membrane-distal CD22 epitope
Velasco-Hernández, Talia (Institut Germans Trias i Pujol. Institut de Recerca contra la Leucèmia Josep Carreras)
Zanetti, S. R. (Institut Germans Trias i Pujol. Institut de Recerca contra la Leucèmia Josep Carreras)
Roca Ho, Heleia (Institut Germans Trias i Pujol. Institut de Recerca contra la Leucèmia Josep Carreras)
Gutiérrez-Agüera, Francisco (Institut Germans Trias i Pujol. Institut de Recerca contra la Leucèmia Josep Carreras)
Petazzi, Paolo (Institut Germans Trias i Pujol. Institut de Recerca contra la Leucèmia Josep Carreras)
Sánchez-Martínez, D. (Institut Germans Trias i Pujol. Institut de Recerca contra la Leucèmia Josep Carreras)
Molina, Oscar (Institut Germans Trias i Pujol. Institut de Recerca contra la Leucèmia Josep Carreras)
Baroni, Matteo Libero (Institut Germans Trias i Pujol. Institut de Recerca contra la Leucèmia Josep Carreras)
Fuster, José Luis (Sección de Oncohematología Pediátrica. Hosp. Clin. Universitario Virgen de la Arrixaca and Instituto Murciano de Investigacion Biosanitaria)
Ballerini, Paola (Department of Pediatric Hemato-oncology. Armand-Trousseau Childrens Hospital)
Bueno, Clara (Institut Germans Trias i Pujol. Institut de Recerca contra la Leucèmia Josep Carreras)
Fernández-Fuentes, Narcís (Universitat de Vic - Universitat Central de Catalunya)
Engel, P. (Universitat de Barcelona. Departament de Biomedicina)
Menéndez Bujan, Pablo (Institut Germans Trias i Pujol. Institut de Recerca contra la Leucèmia Josep Carreras)
Universitat Autònoma de Barcelona

Date:	2020
Abstract:	Background There are few therapeutic options available for patients with B-cell acute lymphoblastic leukemia (B-ALL) relapsing as CD19 - either after chemotherapy or CD19-targeted immunotherapies. CD22-chimeric antigen receptor (CAR) T cells represent an attractive addition to CD19-CAR T cell therapy because they will target both CD22 + CD19 - B-ALL relapses and CD19 - preleukemic cells. However, the immune escape mechanisms from CD22-CAR T cells, and the potential contribution of the epitope binding of the anti-CD22 single-chain variable fragment (scFv) remain understudied. Methods Here, we have developed and comprehensively characterized a novel CD22-CAR (clone hCD22. 7) targeting a membrane-distal CD22 epitope and tested its cytotoxic effects against B-ALL cells both in in vitro and in vivo assays. Results Conformational epitope mapping, cross-blocking, and molecular docking assays revealed that the hCD22. 7 scFv is a high-affinity binding antibody which specifically binds to the ESTKDGKVP sequence, located in the Ig-like V-type domain, the most distal domain of CD22. We observed efficient killing of B-ALL cells in vitro, although the kinetics were dependent on the level of CD22 expression. Importantly, we show an efficient in vivo control of patients with B-ALL derived xenografts with diverse aggressiveness, coupled to long-term hCD22. 7-CAR T cell persistence. Remaining leukemic cells at sacrifice maintained full expression of CD22, ruling out CAR pressure-mediated antigen loss. Finally, the immunogenicity capacity of this hCD22. 7-scFv was very similar to that of other CD22 scFv previously used in adoptive T cell therapy. Conclusions We report a novel, high-affinity hCD22. 7 scFv which targets a membrane-distal epitope of CD22. 4-1BB-based hCD22. 7-CAR T cells efficiently eliminate clinically relevant B- CD22 high and CD22 low ALL primary samples in vitro and in vivo. Our study supports the clinical translation of this hCD22. 7-CAR as either single or tandem CD22-CD19-CAR for both naive and anti-CD19-resistant patients with B-ALL.
Grants:	European Commission 646903 Ministerio de Economía y Competitividad SAF2016-80481-R Instituto de Salud Carlos III PI17-01028
Note:	Altres ajuts: Funding This work was supported by the Obra Social La Caixa (LCF/PR/HR19/52160011), the Spanish Cancer Association and Leo Messi Foundation to PM.
Rights:	Aquest document està subjecte a una llicència d'ús Creative Commons. Es permet la reproducció total o parcial, la distribució, la comunicació pública de l'obra i la creació d'obres derivades, sempre que no sigui amb finalitats comercials, i sempre que es reconegui l'autoria de l'obra original.
Language:	Anglès
Document:	Article ; recerca ; Versió publicada
Subject:	T-lymphocytes ; Cell engineering ; Hematologic neoplasms ; Immunotherapy ; Receptors ; Chimeric antigen
Published in:	Journal for immunotherapy of cancer, Vol. 8 Núm. 2 (november 2020) , p. e000896, ISSN 2051-1426

DOI: 10.1136/jitc-2020-000896
PMID: 32788237

11 p, 5.7 MB

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Research literature > UAB research groups literature > Research Centres and Groups (research output) > Health sciences and biosciences > Institut d'Investigació en Ciencies de la Salut Germans Trias i Pujol (IGTP) > Josep Carreras Leukaemia Research Institute
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Articles > Published articles