AG Thomas Winkler
Focus of research: AG Thomas Winkler
The group of Professor Thomas Winkler is interested in the regulation of processes generating immune receptor diversity and autoimmunity.
Regulation of VDJ-recombination
During the development of B lymphocytes, the genes encoding immunoglobulins are compiled in a process of genetic recombination, that is responsible for the enormous variability of the antibody repertoire. We are interested in the regulation of this process, which is called VDJ-recombination. Although its mechanism is well understood, its regulation is still unclear. For example, recombination of V-, D- and J-segments of all seven antigen-receptor gene clusters (3 immunoglobulin-gene cluster & 4 T-cell receptor gene cluster) occurs through the same enzyme machinery, but its expression is tightly regulated. Antibody genes are exclusively expressed in B cells, while T cell receptor genes are only recombined in T lymphocytes. In addition, recombination of gene segments for the light and heavy receptor chains is coordinated in a timely manner (Fig. 1), leading to each B lymphocyte only expressing one combination of heavy and light chain (a process termed allelic exclusion).
The focus of our research work lies in the approachability of the Ig heavy chain gene cluster for the VDJ recombinase. We investigate epigenetic mechanisms of gene regulation through methods of chromatin analysis (ChIP-Seq, ChIP-on-Chip) and try to identify regulatory sequences within the IgH-gene locus.
Mechanisms behind the emergence and pathogenesis of autoantibodies
Autoantibodies against DNA (ANAs) are characteristic for the autoimmune disease systemic lupus erythematodes (SLE). In our group, we investigate both the mechanisms of immunologic dysregulation that are causal for the emergence of ANAs, as well as their role in SLE pathology, especially for glomerulonephritis. In our projects, we work on murine models of SLE. Herein, we utilize spontaneous and genetically modified disease models, that we established through gene targeting.
Currently, we follow the hypothesis that such autoantibodies arise due to dysregulations during a process called germinal centre reaction. To adress this hypothesis, we use a mouse model overexpressing a patient-derived autoantibody.
Antibody-mediated defense against cytomegaly viruses
Infection with the human cytomegaly virus (HCMV, HHV5) usually occur without onset of symptoms, with the virus being prevalent in 50-90% of the adult human population. Severe disease occurs in patients with a compromised immune system, as for example after an organ graft. Additionally, HCMV is an important congenically transferred pathogen, that can lead to severe prenatal manifestations.
In order to better understand the humoral immune response against this virus, our group cooperates with the group of Prof. Michael Mach from the Institute of Clinical Virology (University Hospital Erlangen). We hope to develop novel therapeutic concepts on the foundation of our findings.
We investigate both the human cytomegaly virus (HCMV) as well as its murine relative (murine cytomegaly virus, MCMV). Utilizing mice, we model MCMV infection in the context of clinically relevant immunosupression after bone-marrow transplantation. Novel therapeutic concepts utilizing memory B cells or monoclonal antibodies are tested in these mouse models. In a cooperation with the University Hospital Erlangen Clinic V, we want to translate these concepts into a clinical setting.
Thomas Winkler on Google Scholar
5 Key Publications
- Schmitt, H., S. Sell, J. Koch, M. Seefried, S. Sonnewald, C. Daniel, T.H. Winkler, and L. Nitschke. 2016. Siglec-H protects from virus-triggered severe systemic autoimmunity. J Exp Med213:1627-1644.
- Sell, S., M. Dietz, A. Schneider, R. Holtappels, M. Mach, and T.H. Winkler. 2015. Control of murine cytomegalovirus infection by gammadelta T cells. PLoS path11:e1004481.
- Pötzsch, S., N. Spindler, A.K. Wiegers, T. Fisch, P. Rucker, H. Sticht, N. Grieb, T. Baroti, F. Weisel, T. Stamminger, L. Martin-Parras, M. Mach, and T.H. Winkler. 2011. B cell repertoire analysis identifies new antigenic domains on glycoprotein B of human cytomegalovirus which are target of neutralizing antibodies. PLoS path 7:e1002172.
- Weisel, F.J., U.K. Appelt, A.M. Schneider, J.U. Horlitz, N. van Rooijen, H. Korner, M. Mach, and T.H. Winkler. 2010. Unique requirements for reactivation of virus-specific memory B lymphocytes. J Immunol185:4011-4021.
- Wellmann, U., M. Letz, M. Herrmann, S. Angermuller, J.R. Kalden, and T.H. Winkler. 2005. The evolution of human anti-double-stranded DNA autoantibodies. Proc Nat Acad Sci USA 102:9258-9263.