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van Veelen, P. A.

Publications and source records attributed to van Veelen, P. A..

2 recordsLinked to original sources

PAKC: A novel Panel of HLA class I Antigen presentation machinery Knockout Cells from the same genetic origin

With the emergence of immunotherapies, the understanding of functional HLA class I antigen presentation to T cells is more relevant than ever. Current knowledge on antigen presentation is based on decades of research in a wide variety of cell types with varying antigen presentation machinery (APM) expression patterns, proteomes and HLA haplotypes. This diversity complicates the establishment of individual APM contributions to antigen generation, selection and presentation. Therefore, we generated a novel Panel of APM Knockout Cell lines (PAKC) from the same genetic origin. After CRISPR/Cas9 genome-editing of ten individual APM components in a human cell line, we derived clonal cell lines and confirmed their knockout status and phenotype. We then show how PAKC will accelerate research on the functional interplay between APM components and their role in antigen generation and presentation. This will lead to improved understanding of peptide-specific T cell responses in infection, cancer and autoimmunity. Key pointsO_LIWe generated a panel of cell lines to study HLA class I antigen presentation C_LIO_LIWe show how this will spark research in infection, tumor biology and autoimmunity C_LI

immunology

A Small-Molecule Activity-Based Probe for Monitoring Ubiquitin C-terminal Hydrolase L1 (UCHL1) Activity in Live Cells and Zebrafish Embryos

Many reagents have been emerged to study the function of specific enzymes in vitro. On the other hand, target specific reagents are scarce or need improvement allowing investigations of the function of individual enzymes in a cellular context. We here report the development of a target-selective fluorescent small-molecule activity-based DUB probe that is active in live cells and whole animals. The probe labels active Ubiquitin Carboxy-terminal Hydrolase L1 (UCHL1), also known as neuron-specific protein PGP9.5 (PGP9.5) and parkinson disease 5 (PARK5), a DUB active in neurons that constitutes 1-2% of total brain protein. UCHL1 variants have been linked with the neurodegenerative disorders Parkinsons and Alzheimers disease. In addition, high levels of UCHL1 also correlate often with cancer and especially metastasis. The function of UCHL1 or its role in cancer and neurodegenerative disease is poorly understood and few UCHL1 specific research tools exist. We show that the reagents reported here are specific for UCHL1 over all other DUBs detectable by competitive activity-based protein profiling and by mass spectrometry. Our probe, which contains a cyanimide reactive moiety, binds to the active-site cysteine residue of UCHL1 irreversibly in an activity-dependent manner. Its use is demonstrated by labelling of UCHL1 both in vitro and in cells. We furthermore show that this probe can report UCHL1 activity during the development of zebrafish embryos.

biochemistry