Cellular Immunology

Cellular Immunology 304–305 (2016) 49–54

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

Liren Qian, Dan Li, Lie Ma, Ting He, Feifei Qi, Jianliang Shen, Xin-an Lu

a Department of Hematology, Navy General Hospital, No. 6 Fucheng Road, Haidian District, Beijing 100048, China

b Department of Health Management, Navy General Hospital, No. 6 Fucheng Road, Haidian District, Beijing 100048, China

c Department of Respiration, Navy General Hospital, No. 6 Fucheng Road, Haidian District, Beijing 100048, China

d Beijing Immunochina Medical Science & Technology Co., Ltd., No. 8 Shengmingyuan Road, Changping District, Beijing 102200, China

ABSTRACT

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.

©2016 Elsevier Inc. All rights reserved.

Keywords: scFv, Humanization, CARs, Xenograft