"I undertook training in the Yazdanbakhsh lab at the Leiden University Medical Center to learn how to use mass cytometry (CyTOF). This technique was applied to nasal biopsies collected in the experimental human pneumococcal challenge (EHPC) model. We analysed stored samples from 20 volunteers who had been experimentally challenged with Spn type 6B (80,000 CFU/nostril). Of these 20, 8 became colonized and 12 were protected against colonization.
This training grant allowed me to analyse these stored samples using CyTOF, which is a unique approach to get a comprehensive insight into which cellular immune responses are elicited in response to Spn carriage. The Yazdanbakhsh lab has an established protocol with 41 antibodies labelled with heavy metals that show no spectral overlap and thus can characterize immune cells and networks at an unprecedented detail. Samples were transported to the LUMC, thawed, barcoded, stained and analysed using a combination of their previously developed CyTOF panels. I learned how to perform this experiment and analysed the resulting data with the ‘cytosplore’ software that was developed by the LUMC together with the TU Delft.
This project allowed us to maximize the scientific output from very precious tissue samples collected following human infection challenge. It has identified new targets cell populations for us to explore in other samples. In addition, this project led to the generation of data that was used to support grant applications and is currently being drafted for publication. The links established via this project are strong and there will likely be continued collaboration with the LUMC.