Browsing by Author "Middelkamp, Vera"

The main development of T cells takes place in the thymus. However, T cells that have just exited the thymus, called Recent Thymic Emigrants, are not yet fully matured and thus have different characteristics and functionalities than mature peripheral T cells. Several biomarkers exist for these Recent Thymic Emigrants in CD4 positive cells, but not in CD8 positive cells. Therefore, human (CD8) RTEs are understudied, despite their critical role in the developing immune system, holding back research in the field of immunological biology, autoimmune disease, cancer, aging and more. Therefore, this thesis aims to identify biomarkers of CD8 positive Recent Thymic Emigrants. To this extent, nearly egress-ready thymocytes, fully egress-ready thymocytes and naïve PBMCs were obtained from pediatric donors, and both bulk and single cell RNA sequencing was performed to provide insight into the gene expression in these stages of T cell development and obtain candidate markers. These candidate markers can then be validated using flow cytometry and T cell receptor excision circle assays (the current golden standard for measuring Recent Thymic Emigrants). Both these methods have been developed and optimized, and some potential candidate markers have been identified. However, some shortcomings like limited sample size and missing single cell data need to be addressed, before the described methods of testing candidate markers can be applied and any markers can be exposed.