Cytotoxic T Cells in Immunity and Self-Tolerance
8 April 2021
Ondřej Štěpánek, Ph.D.
Groupleader of Laboratory of Adaptive Immunity, Institute of Molecular Genetics CAS, Prague
"We consider T cells as the most fascinating cells in our bodies. Unlike the vast majority of other somatic cells, each T cell is genetically unique, because it shuffles the pieces of DNA that encode for its antigenic receptor. It means that each single T cell has its unique antigenic receptor with a unique specificity. We can compare the T cells to an army of soldiers, each of them carrying a unique weapon used in a specific situation. When the organism is infected with a pathogen, there are always a couple of T cells with the right weapon/receptor that initiate the adaptive immune response. On the other hand, too much of T-cell reactivity might induce friendly fire, or autoimmunity in immunological terms.
Our long-term research interest is to understand how the T-cell antigenic receptor (TCR) and other receptors on T cells transduce the signals from outside to inside the cells. In particular, we focus on the role of CD4/CD8 coreceptors and Lck in the TCR signaling. We also use mass-spectrometry to identify proteins that are involved in the signal transduction of inhibitory and costimulatory receptors. These receptors are very powerful, because they play key roles in the T-cell decision to initiate the immune response or ignore the signals coming from the TCR. Clinical modulations of these receptors show very promising results in the cancer immunotherapy. We aim to uncover novel players in this process that might represent new targets for such therapy."
See more information at Dr. Štěpánek´s research group website.
About the lecture
Current SARS-CoV2 pandemic highlighted the general lack of understanding of the mechanisms of T-cell memory and of the diversity of cytotoxic T-cell responses in general.
In contrast to circulating neutralizing antibodies, memory T-cell responses are much less affected by novel mutations or variants of viruses.
In this lecture, I will highlight major mechanisms of the immune memory. Moreover, I will present the results of our research focusing on the comparison of the responses of naive and memory T cells on per cell basis.