Arthritis in KRN T Cell Receptor-Transgenic Mice Does Not Require Interleukin-17 or Th17 Cells

作者:Auger Jennifer L; Cowan Hannah M; Engelson Brianna J; Kashem Sakeen W; Prinz Immo; Binstadt Bryce A*
来源:Arthritis & Rheumatology, 2016, 68(8): 1849-1855.
DOI:10.1002/art.39646

摘要

Objective. Th17 cells and interleukin-17 (IL-17) cytokine family members are implicated in the pathogenesis of many rheumatic diseases. Most studies in mouse models of inflammatory arthritis have demonstrated a key role for the proinflammatory cytokine IL-17A and its receptor, the IL-17 receptor (IL-17R) A/C heterodimer. The aim of this study was to use a rigorous genetic approach to evaluate the contribution of Th17 cells and IL-17 in the autoantibody-dependent KRN T cell receptor-transgenic mouse model of arthritis. Methods. We bred KRN mice expressing the major histocompatibility complex class II molecule A(g7) (referred to as K/B/g7 mice) and genetically lacking the related cytokines IL-17A and IL-17F or their critical receptor subunit, IL-17RA. Using bone marrow transplantation, we generated mice in which hematopoietic cells from K/B/g7 donor mice lacked the key Th17-differentiating transcription factor, retinoic acid receptor-related orphan nuclear receptor gamma t (Ror gamma t). Results. K/B/g7 mice lacking both IL-17A and IL-17F produced normal titers of pathogenic autoantibodies, and arthritis developed in a typical manner. Similarly, neither IL-17RA nor Rorgt expression by hematopoietic cells was required for disease development in this model. Conclusion. Despite prior reports suggesting that Th17 cells and IL-17A are crucially involved in the pathogenesis of arthritis in K/BxN mice, the results presented here provide genetic evidence that IL-17A and IL-17F, IL-17RA, and Rorgt expression by hematopoietic cells are dispensable for normal arthritis progression in the K/B/g7 mouse model system. We discuss potential explanations for the discrepancies between these 2 highly similar model systems. These findings plus those in other mouse models of arthritis provide insight regarding why therapeutic biologic agents targeting the Th17/IL-17 axis are beneficial in some human rheumatic diseases but not others.

  • 出版日期2016-8