Association of variant alleles of mannose binding lectin with severity of pulmonary disease in cystic fibrosis: cohort study

Abstract

Prognosis of cystic fibrosis is conditioned by the severity of pulmonary damage, which is related to infectious complications. The group of partial ∂F508 homozygous patients with cystic fibrosis shows a substantial variability in clinical expression of the severity of lung disease, which could be explained by the influence of modulating genes1 that are probably related to the efficiency of host immune factors in fighting against infection in patients' lungs. Mannose binding lectin, a protein of the innate immune system, is involved in opsonisation and phagocytosis of micro-organisms. The mannose binding lectin gene shows three major allelic variants that are responsible for a decrease of the protein plasma concentration, an opsonic defect, and a common immunodeficiency.2 We investigated the possible modulating role of mannose binding lectin because studies have shown (a) that homozygosity or compound heterozygosity for mannose binding lectin variant alleles predisposes to recurrent infections including lung infections and (b) that Staphyloccus …