Bronchoalveolar lavage fluid peptidomics suggests a possible matrix metalloproteinase-3 role in bronchopulmonary dysplasia.
BACKGROUND
Bronchoalveolar lavage fluid (BALF) is an important diagnostic source to investigate molecular changes occurring in lung disorders. The objective of this study was to assess and compare the peptidomic profiles of BALF from premature neonates with and without bronchopulmonary dysplasia (BPD).


METHODS
Samples were obtained on the 3rd day of life from 34 neonates with gestational age <or=32 weeks. Two pools of samples from patients with and without BPD were analyzed by high performance liquid chromatography. Several differentially expressed peptides were collected and sequenced. Moreover, samples from single donors were analyzed by liquid chromatography-electrospray ionization mass spectrometry to define the molecular mass values of various peptides and to quantify their expression. Levels of some matrix metalloproteinases and their tissue inhibitors were also determined in single samples.


RESULTS
Neonates of the BPD group (N = 16) showed significantly lower mean gestational age and birth weight with respect to the no-BPD group (N = 18; P < 0.0001). Levels of six peptides were significantly higher in BPD patients (P < 0.05). Two of them were identified as the albumin fragments 1-21 (2,428 Da) and 399-406 (956 Da). Levels of matrix metalloproteinase-3 (MMP-3) enzyme probably involved in albumin fragment generation were also significantly higher in the BPD group compared to the no-BPD group (P < 0.05), whereas the levels of tissue inhibitor of metalloproteinases-1 were significantly lower (P < 0.05). Levels of albumin fragments and MMP-3 showed a significant correlation (P < 0.05).


CONCLUSIONS
This study shows that proteomic techniques can be applied to investigate the involvement of proteolytic enzymes on the airways of mechanically ventilated premature infants.
Division of Neonatology, Department of Pediatrics, School of Medicine, Catholic University, Largo F Vito 1, 00168 Rome, Italy. vento@rm.unicatt.it
Giovanni
G
Vento
Chiara
C
Tirone
Paola
P
Lulli
Ettore
E
Capoluongo
Franco
F
Ameglio
Simona
S
Lozzi
Francesco
F
Cota
Fabio
F
Mosca
Costantino
C
Romagnoli
Irene
I
Messana
Massimo
M
Castagnola
Rosanna
R
Inzitari
D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry*; D001997:Bronchopulmonary Dysplasia / Q000378:metabolism* / Q000473:pathology*; D005260:Female; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D008168:Lung / Q000378:metabolism; D008297:Male; D019278:Matrix Metalloproteinase 3 / Q000032:analysis* / Q000378:metabolism*
D019278:Matrix Metalloproteinase 3