| 1. |
- Bersellini Farinotti, Alex, et al.
(author)
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Cartilage-binding antibodies induce pain through immune complex-mediated activation of neurons
- 2019
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In: Journal of Experimental Medicine. - : Rockefeller University Press. - 1540-9538 .- 0022-1007. ; 216:8, s. 1904-1924
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Journal article (peer-reviewed)abstract
- Rheumatoid arthritis-associated joint pain is frequently observed independent of disease activity, suggesting unidentified pain mechanisms. We demonstrate that antibodies binding to cartilage, specific for collagen type II (CII) or cartilage oligomeric matrix protein (COMP), elicit mechanical hypersensitivity in mice, uncoupled from visual, histological and molecular indications of inflammation. Cartilage antibody-induced pain-like behavior does not depend on complement activation or joint inflammation, but instead on tissue antigen recognition and local immune complex (IC) formation. smFISH and IHC suggest that neuronal Fcgr1 and Fcgr2b mRNA are transported to peripheral ends of primary afferents. CII-ICs directly activate cultured WT but not FcRγ chain-deficient DRG neurons. In line with this observation, CII-IC does not induce mechanical hypersensitivity in FcRγ chain-deficient mice. Furthermore, injection of CII antibodies does not generate pain-like behavior in FcRγ chain-deficient mice or mice lacking activating FcγRs in neurons. In summary, this study defines functional coupling between autoantibodies and pain transmission that may facilitate the development of new disease-relevant pain therapeutics.
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| 2. |
- Kolossov, Eugen, et al.
(author)
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Engraftment of engineered ES cell-derived cardiomyocytes but not BM cells restores contractile function to the infarcted myocardium
- 2006
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In: Journal of Experimental Medicine. - New York, USA : Rockefeller University Press. - 0022-1007 .- 1540-9538. ; 203:10, s. 2315-2327
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Journal article (peer-reviewed)abstract
- Cellular cardiomyoplasty is an attractive option for the treatment of severe heart failure. It is, however, still unclear and controversial which is the most promising cell source. Therefore, we investigated and examined the fate and functional impact of bone marrow (BM) cells and embryonic stem cell (ES cell)-derived cardiomyocytes after transplantation into the infarcted mouse heart. This proved particularly challenging for the ES cells, as their enrichment into cardiomyocytes and their long-term engraftment and tumorigenicity are still poorly understood. We generated transgenic ES cells expressing puromycin resistance and enhanced green fluorescent protein cassettes under control of a cardiac-specific promoter. Puromycin selection resulted in a highly purified (>99%) cardiomyocyte population, and the yield of cardiomyocytes increased 6-10-fold because of induction of proliferation on purification. Long-term engraftment (4-5 months) was observed when co-transplanting selected ES cell-derived cardiomyocytes and fibroblasts into the injured heart of syngeneic mice, and no teratoma formation was found (n = 60). Although transplantation of ES cell-derived cardiomyocytes improved heart function, BM cells had no positive effects. Furthermore, no contribution of BM cells to cardiac, endothelial, or smooth muscle neogenesis was detected. Hence, our results demonstrate that ES-based cell therapy is a promising approach for the treatment of impaired myocardial function and provides better results than BM-derived cells.
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| 3. |
- Raposo, B., et al.
(author)
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Epitope-specific antibody response is controlled by immunoglobulin V(H) polymorphisms
- 2014
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In: Journal of Experimental Medicine. - : Rockefeller University Press. - 0022-1007 .- 1540-9538. ; 211:3, s. 405-411
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Journal article (peer-reviewed)abstract
- Autoantibody formation is essential for the development of certain autoimmune diseases like rheumatoid arthritis (RA). Anti-type II collagen (CII) antibodies are found in RA patients; they interact with cartilage in vivo and are often highly pathogenic in the mouse. Autoreactivity to CII is directed to multiple epitopes and conserved between mice and humans. We have previously mapped the antibody response to CII in a heterogeneous stock cohort of mice, with a strong association with the IgH locus. We positioned the genetic polymorphisms and determined the structural requirements controlling antibody recognition of one of the major CII epitopes. Polymorphisms at positions S31R and W33T of the associated variable heavy chain (VH) allele were identified and confirmed by gene sequencing. The Fab fragment binding the J1 epitope was crystallized, and site-directed mutagenesis confirmed the importance of those two variants for antigen recognition. Back mutation to germline sequence provided evidence for a preexisting recognition of the J1 epitope. These data demonstrate a genetic association of epitope-specific antibody responses with specific VH alleles, and it highlights the importance of germline-encoded antibodies in the pathogenesis of antibody-mediated autoimmune diseases.
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| 4. |
- Uysal, Hüseyin, et al.
(author)
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Structure and pathogenicity of antibodies specific for citrullinated collagen type II in experimental arthritis
- 2009
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In: Journal of Experimental Medicine. - New York, NY : Rockefeller University Press. - 0022-1007 .- 1540-9538. ; 206:2, s. 449-462
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Journal article (peer-reviewed)abstract
- Antibodies to citrulline-modified proteins have a high diagnostic value in rheumatoid arthritis (RA). However, their biological role in disease development is still unclear. To obtain insight into this question, a panel of mouse monoclonal antibodies was generated against a major triple helical collagen type II (CII) epitope (position 359-369; ARGLTGRPGDA) with or without arginines modified by citrullination. These antibodies bind cartilage and synovial tissue, and mediate arthritis in mice. Detection of citrullinated CII from RA patients' synovial fluid demonstrates that cartilage-derived CII is indeed citrullinated in vivo. The structure determination of a Fab fragment of one of these antibodies in complex with a citrullinated peptide showed a surprising beta-turn conformation of the peptide and provided information on citrulline recognition. Based on these findings, we propose that autoimmunity to CII, leading to the production of antibodies specific for both native and citrullinated CII, is an important pathogenic factor in the development of RA.
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