Effects of different allo-Treg/allo-NK ratios on graft-versus-host disease in transplanted mice

Shunjie Wu; Haizhen Li; Xianchao Wang; Tuanyun Ji; Xiaojun Xu; Qiaohong Yang

doi:10.1016/j.trim.2023.101893

Effects of different allo-Treg/allo-NK ratios on graft-versus-host disease in transplanted mice

Transpl Immunol. 2023 Oct:80:101893. doi: 10.1016/j.trim.2023.101893. Epub 2023 Jul 3.

Authors

Shunjie Wu¹, Haizhen Li¹, Xianchao Wang², Tuanyun Ji², Xiaojun Xu³, Qiaohong Yang⁴

Affiliations

¹ Hematology Darpartment, The Seventh Affiliated Hospital of Sun Yat-sen University, China.
² Department of Pathology and Pathophysiology, School of Basic Medical Sciences, Guangzhou University of Chinese Medicine, China.
³ Hematology Darpartment, The Seventh Affiliated Hospital of Sun Yat-sen University, China. Electronic address: xuxj29@mail.sysu.edu.cn.
⁴ Department of Pathology and Pathophysiology, School of Basic Medical Sciences, Guangzhou University of Chinese Medicine, China. Electronic address: yangqiaohong@gzucm.edu.cn.

PMID: 37406712
DOI: 10.1016/j.trim.2023.101893

Abstract

To investigate the effects of allo-Treg cells, allo-NK cells, and their mixtures in different proportions on Graft-versus-host disease (GVHD) in bone marrow transplant mouse model. In this study, C57BL/6 mice were used as donors, and 6 Gy dose of ⁶⁰Co γ was used as the receptor of BALB/c mice. The recipient mice were divided into NC (normal saline), CON (bone marrow cells), NK (bone marrow cells + NK cells), Treg (bone marrow cells + Treg cells), NK+ Treg (1:1) (bone marrow cells +1:1 ratio of Treg cells, NK cells), and NK+ Treg (6:1) (bone marrow cells +1:6 ratio of Treg cells, NK cells), according to the different injection mode through the tail vein. The differences of white blood cell (WBC), platelet (PLT), clinical manifestations, and GVHD score of target organs (liver, lung, small intestine) in each group after transplantation were observed, and the differences of chimerism rate and survival rate in each group at 28 days after transplantation were compared. The interaction between Treg cells and NK cells in different proportions (1:1, 1:2, 1:6, 1:12) was investigated in vitro in mouse erythroleukemia (MEL) cells of mouse erythroleukemia. The results showed that at the 28th day of transplantation, the clinical manifestations and GVHD scores of target organs of mice in NK+ Treg (1:1) group and NK+ Treg (6:1) group were significantly lower than other groups (P < 0.05); the WBC and PLT counts were significantly higher than other groups (P < 0.05), and the survival time was significantly longer than other groups (P < 0.05); the clinical manifestations and GVHD scores of each target organ in NK+ Treg (1:1) group were significantly lower than those in NK+ Treg (6:1) group (P < 0.05); the chimerism rate of each group was >90% on day 28 after transplantation. In vitro experiments showed that the inhibition of Treg cells on NK cell killing activity was dose-dependent, and the proportion of 1:6 and 1:12, killing activity of NK cell was significantly lower than that of groups 1:1 and 1:2 (P < 0.05), which showed that allo-NK and allo-Treg alone had a significant effect on the improvement of GVHD after transplantation, and Treg cells inhibited the killing activity of NK cells by direct contact and showed a dose-dependent effect.

Keywords: Allo-NK cells; Allo-Treg cells; Bone marrow transplantation; Graft-versus-host disease; Killing activity.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Bone Marrow Transplantation / methods
Graft vs Host Disease*
Leukemia, Erythroblastic, Acute*
Mice
Mice, Inbred BALB C
Mice, Inbred C57BL
T-Lymphocytes, Regulatory / transplantation