@article{KarunakaranSubramanianJinetal.2023, author = {Karunakaran, Mohindar M. and Subramanian, Hariharan and Jin, Yiming and Mohammed, Fiyaz and Kimmel, Brigitte and Juraske, Claudia and Starick, Lisa and N{\"o}hren, Anna and L{\"a}nder, Nora and Willcox, Carrie R. and Singh, Rohit and Schamel, Wolfgang W. and Nikolaev, Viacheslav O. and Kunzmann, Volker and Wiemer, Andrew J. and Willcox, Benjamin E. and Herrmann, Thomas}, title = {A distinct topology of BTN3A IgV and B30.2 domains controlled by juxtamembrane regions favors optimal human γδ T cell phosphoantigen sensing}, series = {Nature Communications}, volume = {14}, journal = {Nature Communications}, doi = {10.1038/s41467-023-41938-8}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-358179}, year = {2023}, abstract = {Butyrophilin (BTN)-3A and BTN2A1 molecules control the activation of human Vγ9Vδ2 T cells during T cell receptor (TCR)-mediated sensing of phosphoantigens (PAg) derived from microbes and tumors. However, the molecular rules governing PAg sensing remain largely unknown. Here, we establish three mechanistic principles of PAg-mediated γδ T cell activation. First, in humans, following PAg binding to the intracellular BTN3A1-B30.2 domain, Vγ9Vδ2 TCR triggering involves the extracellular V-domain of BTN3A2/BTN3A3. Moreover, the localization of both protein domains on different chains of the BTN3A homo-or heteromers is essential for efficient PAg-mediated activation. Second, the formation of BTN3A homo-or heteromers, which differ in intracellular trafficking and conformation, is controlled by molecular interactions between the juxtamembrane regions of the BTN3A chains. Finally, the ability of PAg not simply to bind BTN3A-B30.2, but to promote its subsequent interaction with the BTN2A1-B30.2 domain, is essential for T-cell activation. Defining these determinants of cooperation and the division of labor in BTN proteins improves our understanding of PAg sensing and elucidates a mode of action that may apply to other BTN family members.}, language = {en} } @article{BittnerBobakFeuchtenbergeretal.2011, author = {Bittner, Stefan and Bobak, Nicole and Feuchtenberger, Martin and Herrmann, Alexander M and G{\"o}bel, Kerstin and Kinne, Raimund W and Hansen, Anker J and Budde, Thomas and Kleinschnitz, Christoph and Frey, Oliver and Tony, Hans-Peter and Wiendl, Heinz and Meuth, Sven G}, title = {Expression of K\(_2\)\(_P\)5.1 potassium channels on CD4\(^+\)T lymphocytes correlates with disease activity in rheumatoid arthritis patients}, series = {Arthritis Research \& Therapy}, volume = {13}, journal = {Arthritis Research \& Therapy}, number = {R21}, doi = {10.1186/ar3245}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-139334}, year = {2011}, abstract = {Introduction CD4+ T cells express K2P5.1 (TWIK-related acid-sensitive potassium channel 2 (TASK2); KCNK5), a member of the two-pore domain potassium channel family, which has been shown to influence T cell effector functions. Recently, it was shown that K2P5.1 is upregulated upon (autoimmune) T cell stimulation. The aim of this study was to correlate expression levels of K2P5.1 on T cells from patients with rheumatoid arthritis (RA) to disease activity in these patients. Methods Expression levels of K2P5.1 were measured by RT-PCR in the peripheral blood of 58 patients with RA and correlated with disease activity parameters (C-reactive protein levels, erythrocyte sedimentation rates, disease activity score (DAS28) scores). Twenty patients undergoing therapy change were followed-up for six months. Additionally, synovial fluid and synovial biopsies were investigated for T lymphocytes expressing K2P5.1. Results K2P5.1 expression levels in CD4+ T cells show a strong correlation to DAS28 scores in RA patients. Similar correlations were found for serological inflammatory parameters (erythrocyte sedimentation rate, C-reactive protein). In addition, K2P5.1 expression levels of synovial fluid-derived T cells are higher compared to peripheral blood T cells. Prospective data in individual patients show a parallel behaviour of K2P5.1 expression to disease activity parameters during a longitudinal follow-up for six months. Conclusions Disease activity in RA patients correlates strongly with K2P5.1 expression levels in CD4+ T lymphocytes in the peripheral blood in cross-sectional as well as in longitudinal observations. Further studies are needed to investigate the exact pathophysiological mechanisms and to evaluate the possible use of K2P5.1 as a potential biomarker for disease activity and differential diagnosis.}, language = {en} }