Figure 4. Functional status of cord blood CD4+ T cells.

(A) Experimental design and flow cytometry gating strategy used to determine the expression of cytokines and effector molecules on CD4+ T cells from neonates born to mothers who delivered with spontaneous labor at term (TB) (negative control), those who underwent spontaneous preterm labor and birth without intra-amniotic inflammation (PTL-PTB) (study group), or those who underwent spontaneous preterm labor and birth with intra-amniotic inflammation (PTL-PTB-IAI) (positive control). Isolated T cells were either treated with PMA/ionomycin or left untreated. Red histograms indicate the expression of each T-cell marker, and grey histograms indicate isotype controls. (B) Proportions of CD4+ T cells expressing the type 1 cytokines IFNγ and TNFα and the transcription factor Tbet. (C) Proportions of CD4+ T cells expressing the type 2 cytokines IL-4 and IL-10. (D) Proportion of CD4+ T cells expressing the cytokine IL-9. (E) Proportion of CD4+ T cells expressing the effector molecules granzyme B and perforin. Data are shown as box-and-whisker plots where midlines indicate medians, boxes indicate interquartile ranges, and whiskers indicate minimum and maximum ranges. Asterisks indicate p-values ≤0.05 for paired comparisons between the same samples with and without stimulation. P-values are shown for comparisons between stimulated fetal T cells from each group. NS = no significance. Demographic and clinical characteristics of the study population are shown in Table III.