@article{IckrathSpruegelBeyersdorfetal.2021, author = {Ickrath, Pascal and Spr{\"u}gel, Lisa and Beyersdorf, Niklas and Scherzad, Agmal and Hagen, Rudolf and Hackenberg, Stephan}, title = {Detection of Candida albicans-Specific CD4+ and CD8+ T Cells in the Blood and Nasal Mucosa of Patients with Chronic Rhinosinusitis}, series = {Journal of Fungi}, volume = {7}, journal = {Journal of Fungi}, number = {6}, issn = {2309-608X}, doi = {10.3390/jof7060403}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-239671}, year = {2021}, abstract = {Candida albicans is ubiquitously present, and colonization in the nose and oral cavity is common. In healthy patients, it usually does not act as a pathogen, but in some cases can cause diseases. The influence of C. albicans as a trigger of T cell activation on the pathogenesis of chronic rhinosinusitis (CRS) is controversial, and its exact role is not clear to date. The aim of the present study was to detect and characterize C. albicans-specific CD4+ and CD8+ T cells in patients with CRS, with and without nasal polyps. Tissue and blood samples were collected from patients suffering from chronic rhinosinusitis with (CRSwNP) and without nasal polyps (CRSsNP), and from healthy controls. A peptide pool derived from C. albicans antigen was added to tissue and blood samples. After 6 days, lymphocytes were analyzed by multicolor flow cytometry. Activation was assessed by the intracellular marker Ki-67, and the cytokine secretion was measured. Tissue CD8+ T cells of CRSsNP patients showed a significantly higher proportion of Ki-67+ cells after activation with C. albicans antigen compared to peripheral blood CD8+ T cells. Cytokine secretion in response to C. albicans antigen was similar for all study groups. In this study, C. albicans-specific CD4+ and CD8+ T cells were detected in peripheral blood and mucosal tissue in all study groups. In patients suffering from CRSsNP, C. albicans-specific CD8+ T cells were relatively enriched in the nasal mucosa, suggesting that they might play a role in the pathogenesis of CRSsNP.}, language = {en} } @article{BergfeldDasariWerneretal.2017, author = {Bergfeld, Arne and Dasari, Prasad and Werner, Sandra and Hughes, Timothy R. and Song, Wen-Chao and Hortschansky, Peter and Brakhage, Axel A. and H{\"u}nig, Thomas and Zipfel, Peter F. and Beyersdorf, Niklas}, title = {Direct binding of the pH-regulated Protein 1 (Pra1) from Candida albicans inhibits cytokine secretion by mouse CD4\(^{+}\) T cells}, series = {Frontiers in Microbiology}, volume = {8}, journal = {Frontiers in Microbiology}, number = {844}, doi = {10.3389/fmicb.2017.00844}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-158274}, year = {2017}, abstract = {Opportunistic infections with the saprophytic yeast Candida albicans are a major cause of morbidity in immunocompromised patients. While the interaction of cells and molecules of innate immunity with C. albicans has been studied to great depth, comparatively little is known about the modulation of adaptive immunity by C. albicans. In particular, direct interaction of proteins secreted by C. albicans with CD4\(^{+}\) T cells has not been studied in detail. In a first screening approach, we identified the pH-regulated antigen 1 (Pra1) as a molecule capable of directly binding to mouse CD4\(^{+}\) T cells in vitro. Binding of Pra1 to the T cell surface was enhanced by extracellular Zn\(^{2+}\) ions which Pra1 is known to scavenge from the host in order to supply the fungus with Zn\(^{2+}\). In vitro stimulation assays using highly purified mouse CD4\(^{+}\) T cells showed that Pra1 increased proliferation of CD4\(^{+}\) T cells in the presence of plate-bound anti-CD3 monoclonal antibody. In contrast, secretion of effector cytokines such as IFNγ and TNF by CD4\(^{+}\) T cells upon anti-CD3/ anti-CD28 mAb as well as cognate antigen stimulation was reduced in the presence of Pra1. By secreting Pra1 C. albicans, thus, directly modulates and partially controls CD4\(^{+}\) T cell responses as shown in our in vitro assays.}, language = {en} }