It is her goal to gain a better understanding of age-related changes within the immune system in order to find new ways to prevent the loss of immune function with age. Of practical relevance is the question how vaccination can be optimized for the elderly. In the last decade the group has provided valuable insights into age-related changes in the T cell repertoire which are due to early degenerative changes within the thymus. As the thymus gradually loses its ability to replenish, the naïve T cells decrease while memory and effector T cells increase in number and dominate the repertoire. This can lead to the loss of certain T cell specificities and changes in the polarization of the immune system.
The group of Grubeck-Loebenstein has recently demonstrated that CD8+CD28- effector T cells, which have been linked with low vaccine efficacy, age-related diseases and a shortened life expectancy accumulate not only in old age, but also in persons with latent CMV infections and in adults who underwent thymectomy early in life. Recently they have demonstrated that highly differentiated effector CD8+ T cells are particularly susceptible to apoptosis mediated by extrinsic and intrinsic factors. This susceptibility is due to a decreased capacity of the specific cell type to repair DNA damage. The proneness of effector CD8+ T cells to undergo apoptosis can be overcome by IL-6 and IL-15 signaling, which leads to their survival in niches such as the bone marrow, where the production of these cytokines is high, particularly in old age. The group has also an international reputation as experts on the topic of vaccination in old age and numerous vaccination studies have been performed in the last decade.