Fig. 4

Neutrophil granular enzyme activities and NETs formation among poly JIA patients. A NE activity, B MPO activity, and C percentage of NETs formation of poly JIA patients (N = 3) compared to pediatric healthy controls (HC) (N = 6). NE activity and NETs were similar to HC at diagnosis and increased after anti-inflammatory treatment. MPO activity was decreased in JIA patients at diagnosis in comparison to HC and did not significantly change following treatment. All of the described parameters did not change significantly between the groups. Representative immunofluorescent staining demonstrating NETs formation of D healthy control; E poly JIA patient at diagnosis; and F poly JIA patient after anti-inflammatory treatment. Poly JIA patient at diagnosis exhibits similar NETs formation as healthy control. Following anti-inflammatory treatment, NETs formation in the poly JIA patient increased. White arrows represent NETing neutrophils. None of the parameters including G NE activity, H MPO activity, and I NETs formation exhibited a correlation with cJADAS