title: Use of MMP-8 and MMP-9 to assess disease severity in children with viral lower respiratory tract infections.
abstract: Matrix metalloproteinases (MMPs) play an important role in respiratory inflammatory diseases, such as asthma and chronic obstructive pulmonary disease. It was hypothesized that MMP-8 and MMP-9 may function as biological markers to assess disease severity in viral lower respiratory tract infections in children. MMP-8 and MMP-9 mRNA expression levels in peripheral blood mononuclear cells (PBMCs) and granulocytes obtained in both the acute and recovery phase from 153 children with mild, moderate, and severe viral lower respiratory tract infections were determined using real-time PCR. In addition, MMP-8 and MMP-9 concentrations in blood and nasopharyngeal specimens were determined during acute mild, moderate, and severe infection, and after recovery using ELISA. Furthermore, PBMCs and neutrophils obtained from healthy volunteers were stimulated with RSV, LPS (TLR4 agonist), and Pam3Cys (TLR2 agonist) in vitro. Disease severity of viral lower respiratory tract infections in children is associated with increased expression levels of the MMP-8 and MMP-9 genes in both PBMCs and granulocytes. On the contrary, in vitro experiments showed that MMP-8 and MMP-9 mRNA and protein expression in PBMCs and granulocytes is not induced by stimulation with RSV, the most frequent detected virus in young children with viral lower respiratory tract infections. These data indicate that expression levels of the MMP-8 and MMP-9 genes in both PBMCs and neutrophils are associated with viral lower respiratory tract infections disease severity. These observations justify future validation in independent prospective study cohorts of the usefulness of MMP-8 and MMP-9 as potential markers for disease severity in viral respiratory infections.
authors: Department of Pediatrics, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
authors: Kim H
authors: KH
authors: Brand
authors: Inge M L
authors: IM
authors: Ahout
authors: Ronald
authors: R
authors: de Groot
authors: Adilia
authors: A
authors: Warris
authors: Gerben
authors: G
authors: Ferwerda
authors: Peter W M
authors: PW
authors: Hermans
mesh_terms: D005260:Female; D015870:Gene Expression; D006098:Granulocytes / Q000201:enzymology; D006367:HeLa Cells; D006801:Humans; D007223:Infant; D007963:Leukocytes, Mononuclear / Q000201:enzymology; D008297:Male; D020784:Matrix Metalloproteinase 8 / Q000097:blood / Q000235:genetics / Q000378:metabolism*; D020780:Matrix Metalloproteinase 9 / Q000097:blood / Q000235:genetics / Q000378:metabolism*; D009297:Nasal Mucosa / Q000201:enzymology / Q000821:virology; D009504:Neutrophils / Q000201:enzymology / Q000821:virology; D010614:Pharynx / Q000201:enzymology / Q000821:virology; D011446:Prospective Studies; D018357:Respiratory Syncytial Virus Infections / Q000201:enzymology* / Q000473:pathology / Q000821:virology; D012136:Respiratory Syncytial Viruses; D012141:Respiratory Tract Infections / Q000201:enzymology* / Q000473:pathology / Q000821:virology; D012720:Severity of Illness Index; D018709:Statistics, Nonparametric
chemical_list: C488762:MMP8 protein, human; D020784:Matrix Metalloproteinase 8; D020780:Matrix Metalloproteinase 9