Expression of HLA-DR by mesenchymal stromal cells in the platelet lysate era: an obsolete release criterion for MSCs?
J Transl Med
; 22(1): 39, 2024 01 09.
Article
em En
| MEDLINE
| ID: mdl-38195462
ABSTRACT
BACKGROUND:
According to the definition of the International Society for Cell and Gene Therapy (ISCT), mesenchymal stromal cells (MSCs) do not express HLA-DR. This phenotypic marker as a release criterion for clinical use was established at a time when MSCs were expanded in fetal bovine serum (FBS)-containing media. Replacement of FBS with platelet lysate (PLs) as a medium supplement induced a significantly higher fraction of MSCs to express MHC class II antigens.METHODS:
As this raised concerns that such MSCs may play the role of antigen-presenting cells for T cells, in the current study, we studied major factors that may induce HLA-DR on MSCs by means of flow cytometry and real-time polymerase chain reaction. The immunomodulatory potential of MSCs was assessed by a mixed lymphocyte reaction.RESULTS:
Our results demonstrated that a very low percentage of generated and expanded MSCs in FBS express HLA-DR (median 1.1%, range 0.3-22%) compared to MSCs generated and expanded in PLs (median 28.4%, range 3.3-73.7%). Analysis of the cytokine composition of ten PLs showed a significant positive correlation between the levels of IL-1ß, IL-4, IL-10, IL-17, bFGF and expression of HLA-DR, in contrast to no correlation with the age of MSC donors and HLA-DR (r = 0.21). Both MSCs expressing low and high levels of HLA-DR expressed class II transactivator (CIITA), a master gene coding for these molecules. Our results demonstrate for the first time that MSCs with constitutively high levels of HLA-DR also express moderate levels of indoleamine 2,3-dioxygenase (IDO). Treatment of MSCs with multiple doses of TGF-ß1 at passage 0 (P0) and passage 1 (P1) completely abrogated HLA-DR and IDO expression. In contrast, treatment of MSCs with a single dose of TGF-ß1 after P0 only partially reduced the expression of HLA-DR and CIITA. Remarkably, increased expression of HLA-DR on MSCs that constitutively express high levels of this antigen after overnight incubation with IFN-γ was rather unaffected by incubation with TGF-ß1. However, treatment of MSCs with TGF-ß1 for 24 h completely abrogated constitutive expression of IDO.CONCLUSIONS:
Irrespective of HLA-DR expression at the population level, all MSC preparations significantly inhibited the proliferation of stimulated peripheral blood mononuclear cells, indicating that HLA-DR represents an obsolete release marker for the clinical use of MSCs.Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Fator de Crescimento Transformador beta1
/
Células-Tronco Mesenquimais
Limite:
Humans
Idioma:
En
Ano de publicação:
2024
Tipo de documento:
Article