Multitest software

Whole blood samples from patients with PsA were collected in heparin anticoagulant tubes, and the peripheral blood mononuclear cell suspension was prepared by Ficoll-hypaque density gradient centrifugation. Different antibodies were added in turn for the combined staining of peripheral blood lymphocyte subsets and CD4+T cells. The staining protocol for peripheral blood lymphocyte subsets is as follows: anti-CD3-FITC/CD8-PE/CD45-PercP/CD4-APC antibody is used to label T lymphocytes, anti-CD3-FITC/CD16+56-PE/CD45-PercP/CD19-APC antibody is used to label B lymphocytes and NK cells. CD4+T cell subsets were stained and identified by the following protocols: anti-CD4-FITC/IFN-γ-APC (intracellular staining) for Th1 cells and anti-CD4-FITC/IL-4-PE (intracellular staining) for Th2 Cells, anti-CD4-FITC/IL-17-PE (intracellular staining) to detect Th17 cells, anti-CD4-FITC/CD25-APC/FOXP3-PE (intracellular staining) to identify and detect Treg cells. All immunofluorescent antibodies were purchased from BD Biosciences (BD Biosciences, Franklin Lakes, NJ, USA), blood samples were mixed, incubated, and washed according to the manufacturer’s recommendations, and stained samples were detected within 24 hours using FACSCalibur flow cytometer and BD Multitest software (BD Biosciences, Franklin Lakes, NJ, USA).