Table I.

Percentages of mouse neutrophils with positive histone citrullination, enlarged nucleus, and NET formation after treatment with LPS, PMA, and H₂O₂

Treatment	PAD4+/+			PAD4−/−
	Histone citrullination	Enlarged nucleusab	NET formationcd	Histone citrullination	Enlarged nucleus	NET formation
Control	3.7 ± 0.3%e	UDf	UD	UD	UD	UD
LPS	42.3 ± 3.9%e	23.4 ± 2.7%e	9.5 ± 0.5%e	UD	UD	UD
Cl-amidinef → LPS	8.1 ± 1.3%e	1.2 ± 0.2%e	0.32 ± 0.3%e	UD	UD	UD
PMA	48.5 ± 3%e	10.9 ± 0.3%e	2.7 ± 0.5%e	UD	UD	UD
H2O2	48.3 ± 5.4%e	13.4 ± 1.4%e	3 ± 0.3%e	UD	UD	UD

U.D., undetectable.

^aThe nucleus is scored as an enlarged nucleus if its nuclear diameter is >1.5-fold larger than a regular neutrophil, which is ∼10 µm in diameter.

^bEnlarged nuclei were found to be histone citrullination positive.

^cNET formation is scored if chromatin has extruded and elongated from the nucleus to extracellular space and is confirmed by neutrophil elastase staining after LPS treatment.

^dNETs were found to be histone citrullination positive.

^eAverages and standard deviations were shown (three independent experiments, >500 cells were counted from each experiment).

^f200 µM Cl-amidine was used to treat neutrophils for 30 min before LPS treatment for 3 h.