Experimental Treatment of SIV-Infected Macaques via Autograft of CCR5-Disrupted Hematopoietic Stem and Progenitor Cells

Songlin Yu; Yang Ou; Hongkui Xiao; Jiaojiao Li; Dickson Adah; Shiquan Liu; Siting Zhao; Li Qin; Yongchao Yao; Xiaoping Chen

doi:10.1016/j.omtm.2020.03.004

Experimental Treatment of SIV-Infected Macaques via Autograft of CCR5-Disrupted Hematopoietic Stem and Progenitor Cells

Mol Ther Methods Clin Dev. 2020 Mar 13:17:520-531. doi: 10.1016/j.omtm.2020.03.004. eCollection 2020 Jun 12.

Authors

Songlin Yu^{1

2

3

4}, Yang Ou³, Hongkui Xiao⁴, Jiaojiao Li⁴, Dickson Adah⁴, Shiquan Liu³, Siting Zhao⁴, Li Qin⁴, Yongchao Yao⁴, Xiaoping Chen⁴

Affiliations

¹ Department of Hematology and Key Laboratory of Non-resolving Inflammation and Tumor, The Third Xiangya Hospital, Central South University, Changsha, Hunan Province 410000, P. R. China.
² Postdoctoral Research Station of Clinical Medicine, the Third Xiangya Hospital, Central South University, Changsha, Hunan Province,410000 P. R. China.
³ Hunan Provincial Key Laboratory of Dark Tea and Jin-hua, School of Materials and Chemical Engineering, Hunan City University, Yiyang, Hunan Province 413099, P. R. China.
⁴ State Key Laboratory of Respiratory Disease, Center of Infection and Immunity, Guangzhou Institutes of Biomedicine and Health (GIBH), Chinese Academy of Sciences, Guangzhou, Guangdong Province 510530, P. R. China.

Abstract

Hematopoietic stem cell (HSC)-based gene therapy targeting CCR5 represents a promising way to cure human immunodeficiency virus type 1 (HIV-1) infection. Yet the preclinical animal model with transplantation of autologous CCR5-ablated HSCs remains to be optimized. In this study, four Chinese rhesus macaques of simian immunodeficiency virus (SIV) chronic infection were given long-term antiretroviral therapy (ART), during which peripheral CD34⁺ hematopoietic stem and progenitor cells (HSPCs) were purified and infected with CCR5-specific CRISPR/Cas9 lentivirus (three monkeys) or GFP lentivirus (one monkey). After non-myeloablative conditioning, the CCR5-modified or GFP-labeled HSPCs were autotransplanted to four recipients, and ART was withdrawn following engraftment. All of the recipients survived the process of transplantation. The purified CD34⁺ HSPCs harbored an undetectable level of integrated SIV DNA. The efficiency of CCR5 disruption in HSPCs ranges from 6.5% to 15.6%. Animals experienced a comparable level of hematopoietic reconstuction and displayed a similar physiological homeostasis Despite the low-level editing of CCR5 in vivo (0.3%-1%), the CCR5-disrupted cells in peripheral CD4⁺ Effector Memory T cell (TEM) subsets were enriched 2- to 3-fold after cessation of ART. Moreover, two of the three treated monkeys displayed a delayed viral rebound and a moderately recovered immune function 6 months after ART withdrawal. This study highlights the importance of improving the CCR5-editing efficacy and augmenting the virus-specific immunity for effective treatment of HIV-1 infection.