Differential capability of human cutaneous dendritic cell subsets to initiate Th17 responses.
Human skin-migratory dendritic cells (DCs) have the ability to prime and bias Th1 and Th2 CD4+ T lymphocytes. However, whether human cutaneous DCs are capable of initiating proinflammatory Th17 responses remains undetermined. We report that skin-migratory DCs stimulate allogeneic naive CD4+ T cells that differentiate simultaneously into two distinct effector Th17 and Th1 populations capable of homing to the skin, where they induce severe cutaneous damage. Skin-migratory Langerhans cells (smiLCs) were the main cutaneous DC subset capable of inducing Th17 responses dependent on the combined effects of IL-15 and stabilized IL-6, which resulted in IL-6 trans-signaling of naive CD4+ T cells. Different from smiLCs, purified skin-migratory dermal DCs did not synthesize IL-15 and were unable to bias Th17 responses. Nevertheless, these dermal DCs were capable of differentiating Th17 cells in mixed leukocyte cultures supplemented with IL-15 and stabilized IL-6. Overall, our data demonstrate that human epidermal smiLCs induce Th17 responses by mechanisms different from those previously described and highlight the need to target clinical treatments based on these variations.
Mathers
Alicia R
AR
Department of Dermatology, University of Pittsburgh Medical Center, Pittsburgh, PA 15213, USA.
Janelsins
Brian M
BM
Rubin
Joseph P
JP
Tkacheva
Olga A
OA
Shufesky
William J
WJ
Watkins
Simon C
SC
Morelli
Adrian E
AE
Larregina
Adriana T
AT
D018929:Cell Culture Techniques; D002454:Cell Differentiation / Q000276:immunology; D002465:Cell Movement / Q000276:immunology; D018920:Coculture Techniques; D003713:Dendritic Cells / Q000276:immunology* / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D018836:Inflammation Mediators / Q000502:physiology*; D019409:Interleukin-15 / Q000096:biosynthesis / Q000502:physiology; D020381:Interleukin-17 / Q000502:physiology*; D015850:Interleukin-6 / Q000378:metabolism / Q000502:physiology; D007801:Langerhans Cells / Q000276:immunology / Q000378:metabolism; D007959:Lymphocyte Culture Test, Mixed; D009924:Organ Culture Techniques; D015398:Signal Transduction / Q000276:immunology; D012867:Skin / Q000276:immunology* / Q000378:metabolism* / Q000473:pathology; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology* / Q000378:metabolism* / Q000473:pathology; D018417:Th1 Cells / Q000276:immunology / Q000378:metabolism / Q000473:pathology
D018836:Inflammation Mediators; D019409:Interleukin-15; D020381:Interleukin-17; D015850:Interleukin-6