Search

Granzyme B is found in activated T cells and can be used as a marker of T cell activation. Here, the authors generate a fluorescent probe that can detect Granzyme B levels in tumours, and has the potential to be used as a biomarker of response to immunotherapy.

Dendritic cells have been investigated for cell-based immunotherapy for various applications. The low abundance of dendritic cells in blood hampers their clinical application, resulting in the use of monocyte-derived dendritic cells as an alternative cell type. Limited knowledge is available regarding blood-circulating human dendritic cells, which can be divided into three subsets: type 2 conventional dendritic cells, type 1 conventional dendritic cells, and plasmacytoid dendritic cells. These subsets exhibit unique and desirable features for dendritic cell-based therapies. To enable efficient and reliable human research on dendritic cell subsets, we developed an efficient isolation protocol for the three human dendritic cell subsets, resulting in pure populations. The sequential steps include peripheral blood mononuclear cell isolation, magnetic-microbead lineage depletion (CD14, CD56, CD3, and CD19), and individual magnetic-microbead isolation of the three human dendritic cell subsets.Graphical overviewScheme of the dendritic cell (DC) isolation protocol. Starting material for this process is human blood (buffy coat or aphaeresis). From that, peripheral blood mononuclear cells (PBMCs) are isolated by using ficoll gradient centrifugation. Then, an enrichment for DCs is performed using semi-automated equipment. From the enriched fraction, DC subsets are obtained by magnetic cell sorting.

Ovarian cancer is one of the most fatal tumors in women. Due to a lack of symptoms and adequate screening methods, patients are diagnosed at advanced stages with extensive tumor burden (Jelovac and Armstrong, 2011). Interestingly, ovarian cancer metastasis is generally found within the peritoneal cavity rather than other tissues (Lengyel, 2010; Tan et al., 2006). The reason behind this tissue tropism of the peritoneal cavity remains elusive. A prominent feature of this selectivity is ascites, the accumulation of fluid within the peritoneal cavity, containing, amongst others, immune cells, tumor cells and various soluble factors that can be involved in the progression of ovarian cancer (Kipps et al., 2013). The protocol described here is used to isolate mononuclear cells from ascites to study the functionality of the immune system within the peritoneal cavity.