The Geiger lab
T cells are key players in the immune system with the ability to detect and eliminate infected cells and tumors. We study molecular regulations underlying T cell activation and anti-tumor activity. For this, we use a wide range of technologies including mass spectrometry-based proteomics, functional genomics, mouse models and microfluidics-based systems. Our projects aim to provide detailed insights into T cell functionality that can be translated into the clinic to improve anti-cancer immunotherapies.
Rapid Identification of T cell Receptors that recognize Tumor Antigens
We develop workflows to efficiently isolate T cells that recognize liver tumor antigens. Tumor-reactive T cells can be grown to large numbers and used for adoptive T cell therapies, a highly personalized form of cancer therapy. In collaboration with the research group of Andrew deMello (ETH Zürich), we use droplet-based microfluidics systems to manipulate and analyze single T cells in a high-throughput format.
We use droplet-based microfluidics devices that are developped in the laboratory of Professor deMello.
sustaining T cell preparedness
in Nature Immunology, August 2020
In response to pathogenic threats, naive T cells rapidly transition from a quiescent to an activated state, yet the underlying mechanisms are incompletely understood. Using a pulsed SILAC approach, we investigated the dynamics of mRNA translation kinetics and protein turnover in human naive and activated T cells. Our datasets uncovered that transcription factors maintaining T cell quiescence had constitutively high turnover, which facilitated their depletion following activation. Furthermore, naive T cells maintained a surprisingly large number of idling ribosomes as well as 242 repressed mRNA species and a reservoir of glycolytic enzymes. These components were rapidly engaged following stimulation, promoting an immediate translational and glycolytic switch to ramp up the T cell activation program. Our data elucidate new insights into how T cells maintain a prepared state to mount a rapid immune response, and provide a resource of protein turnover, absolute translation kinetics and protein synthesis rates in T cells (https://www.immunomics.ch).
in Cell, October 2016
Metabolic activity is intimately linked to T cell fate and function. Using high-resolution mass spectrometry, we generated dynamic metabolome and proteome profiles of human primary naive T cells following activation. We discovered critical changes in the arginine metabolism that led to a drop in intracellular L-arginine concentration. Elevating L-arginine levels induced global metabolic changes including a shift from glycolysis to oxidative phosphorylation in activated T cells and promoted the generation of central memory-like cells endowed with higher survival capacity and, in a mouse model, anti-tumor activity. Proteome-wide probing of structural alterations, validated by the analysis of knockout T cell clones, identified three transcriptional regulators (BAZ1B, PSIP1, and TSN) that sensed L-arginine levels and promoted T cell survival. Thus, intracellular L-arginine concentrations directly impact the metabolic fitness and survival capacity of T cells that are crucial for anti-tumor responses.
in Nature Immunology, May 2017
The immune system is unique in its dynamic interplay between numerous cell types. However, a system-wide view of how immune cells communicate to protect against disease has not yet been established. We applied high-resolution mass-spectrometry-based proteomics to characterize 28 primary human hematopoietic cell populations in steady and activated states at a depth of >10,000 proteins in total. Protein copy numbers revealed a specialization of immune cells for ligand and receptor expression, thereby connecting distinct immune functions. By integrating total and secreted proteomes, we discovered fundamental intercellular communication structures and previously unknown connections between cell types. Our publicly accessible (http://www.immprot.org/) proteomic resource provides a framework for the orchestration of cellular interplay and a reference for altered communication associated with pathology.
Meet the lab
We welcome all applications from individuals who are passionate about applying new technologies to studying the immune response to tumors. Please contact Roger with your CV and a cover letter.