The novel anti-CD19 chimeric antigen receptors with humanized scFv (single-chain variable fragment) trigger leukemia cell killing.

The molecular design of CARs (Chimeric Antigen Receptors), especially the scFv, has been a major part to use of CAR-T cells for targeted adoptive immunotherapy. To address this issue, we chose a vector backbone encoding a second-generation CAR based on efficacy of a murine scFv-based CAR. Next, we generated a panel of humanized scFvs and tested in vitro for their ability to direct CAR-T cells to specifically lyse, proliferate, and secrete cytokines in response to antigen-bearing targets. Furthermore, in a xenograft model of lymphoma, human T cells expressing humanized scFvs exhibited the same anti-tumor efficacy as those expressing murine scFv and prolonged survival compared with cells expressing control CAR. Therefore, we uncovered CARs expressing humanized scFv domain that contribute the similar enhanced antileukemic efficacy and survival in tumor bearing mice. These results provide the basis for the future clinical studies of CAR-T cells transduced with humanized scFv directed to CD19.

Qian L ，Li D ，Ma L ，He T ，Qi F ，Shen J ，Lu XA ... -  《-》

Function of Novel Anti-CD19 Chimeric Antigen Receptors with Human Variable Regions Is Affected by Hinge and Transmembrane Domains.

Anti-CD19 chimeric antigen receptor (CAR) T cells have caused remissions of B cell malignancies, but problems including cytokine-mediated toxicity and short persistence of CAR T cells in vivo might limit the effectiveness of anti-CD19 CAR T cells. Anti-CD19 CARs that have been tested clinically had single-chain variable fragments (scFvs) derived from murine antibodies. We have designed and constructed novel anti-CD19 CARs containing a scFv with fully human variable regions. T cells expressing these CARs specifically recognized CD19+ target cells and carried out functions including degranulation, cytokine release, and proliferation. We compared CARs with CD28 costimulatory moieties along with hinge and transmembrane domains from either the human CD28 molecule or the human CD8α molecule. Compared with T cells expressing CARs with CD28 hinge and transmembrane domains, T cells expressing CARs with CD8α hinge and transmembrane domains produced lower levels of cytokines and exhibited lower levels of activation-induced cell death (AICD). Importantly, CARs with hinge and transmembrane regions from either CD8α or CD28 had similar abilities to eliminate established tumors in mice. In anti-CD19 CARs with CD28 costimulatory moieties, lower levels of inflammatory cytokine production and AICD are potential clinical advantages of CD8α hinge and transmembrane domains over CD28 hinge and transmembrane domains.

Alabanza L ，Pegues M ，Geldres C ，Shi V ，Wiltzius JJW ，Sievers SA ，Yang S ，Kochenderfer JN ... -  《-》

Construction of a new anti-CD19 chimeric antigen receptor and the anti-leukemia function study of the transduced T cells.

An N ，Tao Z ，Li S ，Xing H ，Tang K ，Tian Z ，Rao Q ，Wang M ，Wang J ... -  《Oncotarget》

A tandem CD19/CD20 CAR lentiviral vector drives on-target and off-target antigen modulation in leukemia cell lines.

Schneider D ，Xiong Y ，Wu D ，Nӧlle V ，Schmitz S ，Haso W ，Kaiser A ，Dropulic B ，Orentas RJ ... -  《Journal for ImmunoTherapy of Cancer》

Fully human CD19-specific chimeric antigen receptors for T-cell therapy.

Sommermeyer D ，Hill T ，Shamah SM ，Salter AI ，Chen Y ，Mohler KM ，Riddell SR ... -  《-》