TABLE 3

Expression patterns of matrix metalloproteinases (MMPs) during infection and free neutrophil elastase (NE) activity in very young children with cystic fibrosis

	No current infection	Infected^#	p-value	No NE activity	Free NE activity^¶	p-value
MMP-2 ng·mL^-1§	3.50 (3.50–10.77)	3.50 (3.50–5.87)	0.2166	8.15 (3.50–13.43)^##	3.50 (3.50–3.50)^##	<0.0001
MMP-9 ng·mL^-1§	465.70 (25.00–1029.00)^¶¶	1406.00 (527.60–4055.00)^¶¶	0.0018	269.50 (25.00–727.00)^##	1494.00 (25.00–4791.00)^##	<0.0001
TIMP-1 ng·mL^-1§	16.98 (7.96–31.34)	17.94 (9.54–25.12)	0.8403	14.40 (7.28–22.40)^##	19.91 (14.41–37.18)^##	0.0406
TIMP-2 ng·mL^-1§	1.14 (0.84–2.17)	1.24 (0.81–1.68)	0.7778	1.05 (0.68–1.41)^##	1.46 (0.92–2.18)^##	0.0097
MMP-2/TIMP-2 ratio	5.41 (2.10–11.02)	3.33 (2.17–9.72)	0.4495	9.59 (4.14–19.97)^##	2.73 (1.61–3.65)^##	<0.0001
MMP-9/TIMP-1 ratio	21.19 (4.18–70.66)^¶¶	77.53 (34.95–146.40)^¶¶	0.0037	13.81 (6.16–70.28)^##	84.70 (31.28–193.50)^##	0.0018
Pro-MMP-9 AU^ƒ	17.29±10.73^¶¶	25.54±10.40^¶¶	0.0028	16.02±9.33^##	26.55±10.69^##	<0.0001
Active MMP-9 AU^ƒ	11.63±10.11^¶¶	21.22±14.38^¶¶	0.0029	6.70±4.69^##	25.85±11.90^##	<0.0001
Activation ratio	0.67±0.38	0.86±0.66	0.6002	0.46±0.23^##	1.06±0.60^##	<0.0001

Data are presented as median (interquartile range) or mean±sd. Bold text represents statistical significance. TIMP: tissue inhibitor of metalloproteinase; AU: arbitrary units. ^#: bronchoalveolar lavage fluid (BALF) with >10⁴ bacterial CFU·mL^-1; ^¶: BALF >200 ng·mL^-1 (>6.78 nM); ^§: samples below detection range were reported as half the lower limit; ^ƒ: integrated intensity of MMP band as AU; ^##: statistical significance between no NE activity and free NE activity; ^¶¶: statistical significance between no current infection and infected.