Complement and regulatory T cells: The effect of complement on regulatory T cell responses in a mouse retrovirus model.

• Applicant: Professor Dr. Ulf Dittmer
• Subject Area: Virology
• Term: from 2016 to 2019
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 282999617

Establishment of chronic viral infections might be a consequence of the induction and the expansion of regulatory T cells (Tregs). Growing evidence suggests that dendritic cells (DC) are involved in the expansion of Tregs but the mechanisms of DC-Treg interaction are still elusive. Using the Friend virus model, a mouse model for chronic retroviral infections, we found an impaired Treg expansion in knock-out mice deficient for the complement component C3. Thus, we want to elucidate the role of complement in the induction of Treg responses during retroviral infections. To this end, we will study to which extent complement-opsonization of retroviral particles influences the expansion of Tregs via antigen-presenting DCs. We will further test if interfering with complement activation and opsonization affects the expansion of Tregs. The studies will extend our understanding about the interaction of Tregs and DCs, which might potentially be important to therapeutically overcome immune evasion in chronic viral infections.

• DFG Programme: Research Grants
• International Connection: Austria
• Co-Investigators: Dr. Zoltan Banki; Professor Dr. Heribert Stoiber