CD8A and infection: Statistically, no difference in the proportion of potential CTL or NKT was shown between sows with and without transplacental infection (Table 1), but a slightly higher frequency of CD4 single-positive T cells (CD4 SP, CD4+CD8a–) and a slightly lower frequency of CD4/CD8a double-negative T cells (CD4/CD8a DN) were seen in sows delivering healthy piglets in the whole PBMC and also in T cells (CD3+) (Table 1).