A simple and fast method for the isolation of untouched mouse panDCs from spleen (100.43)

Abstract

Dendritic cells (DCs) control immune responses through their robust antigen presenting activity. Steady-state mouse spleen contains three major DC subsets with distinct functional and phenotypic properties including CD8+ and CD8− conventional DCs (cDCs), and plasmocytoid DCs (pDCs). These subsets are present at a very low frequency (< 4%). Typically, elaborate purification protocols such as FACS-based cell sorting or expansion in culture are needed to obtain enough DCs for subsequent studies. Here, we describe a negative selection method to isolate all DC subsets (panDC) from mouse spleen. This method uses immunomagnetic, column-free cell separation technology (EasySepTM). Briefly, non-DCs are labeled for depletion with biotinylated antibodies and cross-linked to magnetic particles using bispecific antibody complexes. The unwanted cells are then removed using an EasySepTM magnet. The selection steps can be fully automated using RoboSepTM . The panDCs are assessed by flow cytometry and defined as Lin−CD11c+ (cDCs) or Lin−CD11cloPDCA-1+ (pDCs). PanDC purities of 80 ± 7% (n=8) are achieved. The rare pDCs are enriched 36-fold with purity of 11.4 ± 1.4% as compared to 0.3 ± 0.1% in the start spleen. Both CD8+ and CD8− cDC subsets are represented in the cDC fraction. The freshly isolated DCs are not activated but upregulate maturation markers upon stimulation with LPS. This method enables fast, easy isolation of panDCs required for immune regulation studies.