Molecular and functional characterization of allogantigen-specific anergic T cells suitable for cell therapy.
BACKGROUND
CD4(+) regulatory T cells are a specialized subset of T cells that actively control immune responses. Several experimental protocols have been used to expand natural regulatory T cells and to generate adaptive type 1 regulatory T cells for regulatory T-cell-based therapies.


METHODS
The ability of exogenous recombinant human interleukin-10 to induce alloantigen-specific anergy in T cells was investigated and compared to that of interleukin-10 derived from tolerogenic dendritic cells, in mixed lymphocyte cultures. A detailed characterization of the effector functions of the resulting anergized T cells is reported.


RESULTS
Interleukin-10, whether exogenous or derived from tolerogenic dendritic cells, induces a population of alloantigen-specific T cells (interleukin-10-anergized T cells) containing type 1 regulatory T cells, which are anergic and actively suppress alloantigen-specific effector T cells present within the mixed population. Interleukin-10-induced anergy is transforming growth factor-β independent, and is associated with a decreased frequency of alloantigen-specific cytotoxic T lymphocyte precursors, but interleukin-10-anergized T cells are still responsive to third-party, bacterial, and viral antigens. Tolerogenic dendritic cells are more powerful than exogenous interleukin-10 in generating type 1 regulatory T-cell precursors, and are also effective in the context of HLA-matched donors.


CONCLUSIONS
Based on these studies, we have developed an efficient and reproducible in vitro method to generate antigen-specific type 1 regulatory T-cell precursors starting from total peripheral blood cells with minimal cell manipulation and suitable for generating type 1 regulatory T cells for regulatory T-cell-based therapies.
Bacchetta
Rosa
R
San Raffaele Telethon Institute for Gene Therapy (HSR-TIGET), Department of Regenerative Medicine, Stem Cells, and Gene Therapy, Milan, Italy.
Gregori
Silvia
S
Serafini
Giorgia
G
Sartirana
Claudia
C
Schulz
Ute
U
Zino
Elisabetta
E
Tomiuk
Stefan
S
Jansen
Uwe
U
Ponzoni
Maurilio
M
Paties
Carlo Terenzio
CT
Fleischhauer
Katharina
K
Roncarolo
Maria Grazia
MG
D002176:Candida albicans / Q000276:immunology; D049109:Cell Proliferation / Q000187:drug effects; D064987:Cell- and Tissue-Based Therapy / Q000379:methods*; D002478:Cells, Cultured; D017635:Clonal Anergy / Q000187:drug effects / Q000276:immunology*; D003587:Cytomegalovirus / Q000276:immunology; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D007371:Interferon-gamma / Q000378:metabolism; D016753:Interleukin-10 / Q000494:pharmacology; D007519:Isoantigens / Q000276:immunology*; D007963:Leukocytes, Mononuclear / Q000276:immunology / Q000378:metabolism; D007959:Lymphocyte Culture Test, Mixed; D009000:Monocytes / Q000276:immunology / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology / Q000378:metabolism; D013745:Tetanus Toxoid / Q000276:immunology; D016212:Transforming Growth Factor beta / Q000494:pharmacology
D007519:Isoantigens; D013745:Tetanus Toxoid; D016212:Transforming Growth Factor beta; D016753:Interleukin-10; D007371:Interferon-gamma