Effects of PD-L1 released from stored platelets on T cell function
10.13303/j.cjbt.issn.1004-549x.2026.09.010
- VernacularTitle:储存血小板释放PDL1对T细胞功能的影响
- Author:
Shaoheng CHEN
1
;
Nannan PAN
1
;
Pinpin LI
1
;
Lili WANG
1
;
Jun ZHENG
1
;
Fengcheng XU
1
;
Huimin DENG
1
;
Jun ZHANG
1
Author Information
1. Department of Blood Transfusion, Shanghai General Hospital, Shanghai 200080, China
- Publication Type:Journal Article
- Keywords:
platelet storage;
PD-L1;
T cell function;
transfusion-related immunomodulation
- From:
Chinese Journal of Blood Transfusion
2026;39(9):1231-1236
- CountryChina
- Language:Chinese
-
Abstract:
Objective: To investigate the effects of platelet-derived PD-L1 released during storage on T cell proliferation, apoptosis, and cytokine expression. Methods: Apheresis platelets were stored with agitation at 22℃. Platelet supernatant was collected on days 1, 3, 5, and 7 of storage, and then co-cultured with human CD4
and CD8
mixed T cells isolated by magnetic bead sorting. CCK8 assay was used to detect T cell proliferation; flow cytometry was applied to determine T cell apoptosis as well as the expression levels of IFN-γ and GZMB. Additionally, Western blot was employed to examine alterations in downstream signaling molecules of the PD-1 receptor. Results: With the prolongation of platelet storage time, the inhibitory effect of platelet storage medium on T cell proliferation was gradually enhanced, accompanied by suppressed expression of IFN-γ and GZMB, whereas the apoptosis level of T cells increased progressively. Treatment with PD-1 antibody or PD-L1 antibody partially blocked the regulatory effects of platelet storage medium on T cell proliferation, apoptosis, and the expression of IFN-γ and GZMB. Western blot results showed that the phosphorylation levels of p-SHP1 and p-SHP2 were significantly upregulated, whereas p-AKT expression was downregulated in T cells co-cultured with platelet storage medium. Intervention with PD-1 or PD-L1 antibody could partially reverse the above changes in protein expression. Conclusion: During platelet storage, platelet-derived PD-L1 in the storage medium promotes T cell apoptosis and inhibits T cell proliferation as well as the expression of related cytokines in a time-dependent manner. Therefore, platelet-derived PD-L1, as an important immune regulatory mediator, may be involved in transfusion-related immunomodulation (TRIM).
