Characterization of duck peripheral blood cells at single-cell resolution

We performed scRNA-seq for duck peripheral white blood cells. Peripheral blood samples from 45-week-old male specific pathogen-free (SPF) ducks were subjected to scRNA-seq using the 10 × Chromium platform and transcriptional profile of subgroups of duck PWBCs separated according to their physical properties were also generated. The peripheral blood cells pretreated with erythrocyte lysis buffer were firstly separated by density gradient centrifugation using a duck lymphocyte isolation kit (Tianjin Haoyang Biological Technology, Tianjin, China). The cells in pallet were washed with 1640 culture medium and named as “high-density cells”(HDC) . The peripheral blood mononuclear cells (PBMCs), which were located in the middle layer, were further separated by differential adhesion in culture dishes preloaded with sterilized glass coverslips according to the different adherent properties of PBMCs. The cells that tightly adhered to the coverslips situated in the culture dishes within one hour of seeding were named “adherent PBMCs” (ADP). The suspended cells were then transferred into new dishes and cultured for another 24 hours. Then the remaining suspended cells were collected and named as “suspended PBMCs” (SPP).