Figure 2

S. suis strains show differences in the level of association with monocytes and lymphocytes. Porcine peripheral blood mononuclear cells (PBMCs) freshly isolated from porcine blood were incubated with Far Red-labeled S. suis strains (S. suis*FR) at an MOI of 1 for 30 min at 37 ℃, whereby S. suis*FR had been pre-incubated in serum of colostrum-deprived piglets (CDS) for 30 min (cps2, cps14, cps9, and cps7). Monocytes were stained using the myeloid marker CD172a-FITCs and samples were measured by flow cytometry. The levels of associations of S. suis strains with monocytes (A–C) and lymphocytes (D–F) are shown. Each symbol refers to a different piglet. Data shown in one graph was obtained in one experiment. Horizontal lines and error bars represent mean values and SDs. For statistical analysis, paired t-test (cps2 strains 10 vs 483) or one-way analyses of variance (ANOVAs) with Tukey’s multiple comparisons test (cps2 strain 10 vs cps14 strains or cps2 strains vs cps9 vs cps7 strains) were performed. Significant differences are indicated (*p < 0.05, **p < 0.01, ***p < 0.001, and ****p < 0.0001).