2.6. Assessment of the immune response degree

The flow cytometry assay was used for the assessment of the immune response degree as described by Pérez-Cano et al. (27). The sterile spleen tissues were used for obtaining cells, and PBS was used for adjusting the concentration of cell suspension to 2 × 10⁷ cells/ml. Subsequently, the BD OptiBuild™ BV480 Mouse Anti-Rat Cluster of Differentiation (CD)8 (746832, BD, USA), the BD Pharmingen™ PE-Cy™7 Mouse Anti-Rat CD4 (561578, BD, Franklin Lakes, USA), the BD Pharmingen™ PE Mouse Anti-Rat CD3 (554833, BD, USA), the Recombinant Rat IL-17A protein (778701, BioLegend, USA), the Forkhead box protein P3 (FOXP3) antibody (sc-65988, Santa Cruz Biotechnology, Dallas, Texas, USA), and BD Pharmingen™ FITC Mouse Anti-Rat CD25 (553072, BD, NJ, USA) were added for incubation in the dark.