Table 2. Counts of monocyte subsets, monocyte subsets with PD-1 expression, and a percentage of PD-1⁺ cells within each monocyte subset in the blood samples from VLBW infants collected on the 5^th DOL.

Data presented as median and IQR.

	CL MO	IM MO	NC MO	p
MO count (cell/μl); median [IQR]	850 [463–1921]	75 [35–134]	41 [12–106]	p < 0.0001*, Post-hoc tests**: p < 0.0001 for CL MO vs. IM MO, p < 0.0001 for CL MO vs. NC MO, p = 0.0009 for IM MO vs. NC MO
PD-1-positivecount (cell/μl); median[IQR]	2 [0.2–5.42]	8.5 [3–15]	0.33 [0–2]	p < 0.0001*, Post-hoc tests**: p < 0.0001 for CL MO vs. IM MO, p = 0.0011 for CL MO vs. NC MO, p < 0.0001 for IM MO vs. NC MO
PD-1-positive (%); median [IQR]	0.29 [0.05–0.58]	11.6 [6.34–22.6]	1.53 [0.17–4.81]	p < 0.0001*, Post-hoc tests**: p < 0.0001 for CL MO vs. IM MO, p < 0.0001 for CL MO vs. NC MO, p < 0.0001 for IM MO vs. NC MO

*—Kruskal—Wallis test,

**—nonparametric comparisons for each pair using Wilcoxon method

CL MO—classical monocytes, IM MO—intermediate monocytes, NC MO—non-classical monocytes