Interleukin-23 promotes Th17 differentiation by inhibiting T-bet and FoxP3 and is required for elevation of interleukin-22, but not interleukin-21, in autoimmune experimental arthritis.
OBJECTIVE
To examine the role of interleukin-23 (IL-23) in subgroup polarization of IL-17A-positive and/or interferon-gamma (IFNgamma)-positive T cells in autoimmune disease-prone DBA/1 mice with and without collagen-induced arthritis.


METHODS
A magnetic-activated cell sorting system was used to isolate CD4+ T cells from the spleen of naive and type II collagen (CII)-immunized DBA/1 mice. These CD4+ T cells were stimulated in vitro under Th0, Th1, or different Th17 culture conditions. Intracellular staining for IL-17A and IFNgamma was evaluated by flow cytometry. In addition, Th17 cytokines and T helper-specific transcription factors were analyzed by enzyme-linked immunosorbent assay and/or quantitative polymerase chain reaction.


RESULTS
In CD4+ T cells from naive DBA/1 mice, IL-23 alone hardly induced retinoic acid-related orphan receptor gammat (RORgammat), Th17 polarization, and Th17 cytokines, but it inhibited T-bet expression. In contrast, transforming growth factor beta1 (TGFbeta1)/IL-6 was a potent inducer of RORgammat, RORalpha, IL-17A, IL-17F, IL-21, and FoxP3 in these cells. In contrast to TGFbeta1/IL-6, IL-23 was critical for the induction of IL-22 in CD4+ T cells from both naive and CII-immunized DBA/1 mice. Consistent with these findings, IL-23 showed a more pronounced induction of the IL-17A+IFNgamma- subset in CD4+ T cells from CII-immunized mice. However, in CD4+ T cells from naive mice, IL-23 significantly increased the TGFbeta1/IL-6-induced Th17 polarization, including elevated levels of IL-17A and IL-17F and decreased expression of T-bet and FoxP3. Of note, the IL-23-induced increase in IL-17A and IL-17F levels was prevented in T-bet-deficient mice.


CONCLUSIONS
IL-23 promotes Th17 differentiation by inhibiting T-bet and FoxP3 and is required for elevation of IL-22, but not IL-21, levels in autoimmune arthritis. These data indicate different mechanisms for IL-23 and TGFbeta1/IL-6 at the transcription factor level during Th17 differentiation in autoimmune experimental arthritis.
Erasmus MC, University Medical Center, 3015 CE Rotterdam, The Netherlands.
Adriana M C
AM
Mus
Ferry
F
Cornelissen
Patrick S
PS
Asmawidjaja
Jan Piet
JP
van Hamburg
Louis
L
Boon
Rudi W
RW
Hendriks
Erik
E
Lubberts
D000818:Animals; D001169:Arthritis, Experimental / Q000276:immunology*; D015704:CD4 Antigens / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects / Q000276:immunology*; D002454:Cell Differentiation / Q000276:immunology; D017931:DNA Primers; D004797:Enzyme-Linked Immunosorbent Assay; D005091:Exons / Q000235:genetics; D051858:Forkhead Transcription Factors / Q000037:antagonists & inhibitors; D007371:Interferon-gamma / Q000276:immunology; D053759:Interleukin-23 / Q000494:pharmacology*; D007378:Interleukins / Q000235:genetics* / Q000276:immunology; D007438:Introns / Q000235:genetics; D051379:Mice; D008811:Mice, Inbred DBA; D016133:Polymerase Chain Reaction; D012313:RNA / Q000235:genetics / Q000302:isolation & purification; D020825:T-Box Domain Proteins / Q000187:drug effects / Q000235:genetics; D013931:Thromboxanes / Q000172:deficiency; D000097043:Interleukin-22; D000098815:T-bet Transcription Factor; D000098546:Interleukin-21
D015704:CD4 Antigens; D017931:DNA Primers; D051858:Forkhead Transcription Factors; D007371:Interferon-gamma; D053759:Interleukin-23; D007378:Interleukins; D012313:RNA; D020825:T-Box Domain Proteins; D013931:Thromboxanes; D000097043:Interleukin-22; D000098815:T-bet Transcription Factor; D000098546:Interleukin-21; C498833:Foxp3 protein, mouse