Generation and characterisation of therapeutic tolerogenic dendritic cells for rheumatoid arthritis.
OBJECTIVE
Tolerogenic dendritic cells (tolDCs) constitute a promising experimental treatment for targeting autoreactive T cells in autoimmune diseases, including rheumatoid arthritis (RA). The authors' goal is to bring tolDC therapy for RA to the clinic. Here the authors address key translational issues related to the manufacturing of tolDCs from RA patients with current good manufacturing practice (cGMP)-compliant reagents, the stability of tolDCs, and the selection of suitable quality control markers.


METHODS
Human monocyte-derived tolDCs were established from RA patients and healthy controls (HCs) using the immunosuppressive drugs dexamethasone and vitamin D₃, and the cGMP-grade immunomodulator, monophosphoryl lipid A, in the cGMP-compliant medium, CellGroDC. The functionality of tolDCs and tolDC-modulated autologous CD4 T cells was determined by flow cytometry, [³H]thymidine incorporation and ELISA.


RESULTS
Clinical-grade tolDCs established from patients with RA exhibit a typical tolerogenic phenotype of reduced costimulatory molecules, low production of proinflammatory cytokines and impaired stimulation of autologous antigen-specific T cells, comparable to HC tolDCs. Toll-like receptor 2 (TLR-2) was highly expressed by tolDCs but not mature DCs. Furthermore, tolDCs suppressed mature DC-induced T cell proliferation, interferon γ and interleukin 17 production, and rendered T cells hyporesponsive to further stimulation. Importantly, tolDCs were phenotypically stable in the absence of immunosuppressive drugs and were refractory to further challenge with proinflammatory mediators.


CONCLUSIONS
tolDCs established from patients with RA are comparable to those derived from healthy donors. TLR-2 was identified as an ideal marker for quality control of tolDCs. Potently tolerogenic and highly stable, these tolDCs are a promising cellular therapeutic for tailored immunomodulation in the treatment of RA.
Harry
Rachel A
RA
Institute of Cellular Medicine, Newcastle University, Newcastle Upon Tyne, UK.
Anderson
Amy E
AE
Isaacs
John D
JD
Hilkens
Catharien M U
CM
D001172:Arthritis, Rheumatoid / Q000276:immunology* / Q000628:therapy; D001327:Autoimmune Diseases / Q000276:immunology* / Q000628:therapy; D018929:Cell Culture Techniques; D049109:Cell Proliferation; D003713:Dendritic Cells / Q000276:immunology* / Q000637:transplantation; D006801:Humans; D007108:Immune Tolerance; D016130:Immunophenotyping; D007371:Interferon-gamma / Q000096:biosynthesis; D020381:Interleukin-17 / Q000096:biosynthesis; D008213:Lymphocyte Activation / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology
D020381:Interleukin-17; D007371:Interferon-gamma