Mannose-binding lectin gene polymorphism is a modulating factor in repeated respiratory infections.
OBJECTIVE
To clarify how mannose-binding lectin (MBL) participates in the pulmonary defense system.


METHODS
Multicenter retrospective study.


METHODS
Sixty-two patients with unexplained recurrent respiratory infections, 50 patients with nontuberculous mycobacterial infection, 23 patients with aspergillosis, and 49 patients with diffuse panbronchiolitis (DPB). For controls, 52 blood samples were provided by the Blood Donation Center of the Japanese Red Cross Society. For BAL fluid (BALF) evaluation, there were five patients with acute phase pneumonia and five healthy volunteers.


RESULTS
We demonstrated that MBL protein could be directly measured in the BALF from the lungs of patients with pneumonia by means of enzyme-linked immunosorbent assay. Furthermore, we demonstrated that the prevalence of the codon 54 mutation of the MBL gene in 62 patients having repeated respiratory infections was significantly higher compared with healthy control subjects (54.8% vs 32.7%). The prevalence of the MBL mutant genotype among patients with DPB was higher (51.1%) than in the rest of the patients. In contrast, the prevalence of the MBL mutant genotype among patients with nontuberculous mycobacteria or Aspergillus chronic infection was not significantly different from that in control subjects (44.0% and 34.8%).


CONCLUSIONS
Our results suggest that MBL may play an important role in modulating the inflammatory response against repeated microbial infections.
Gomi
Kazunori
K
Department of Respiratory Oncology and Molecular Medicine, Institute of Development, Aging, and Cancer, Tohoku University, Sendai, Japan. gomi@idac.tohoku.ac.jp
Tokue
Yutaka
Y
Kobayashi
Takao
T
Takahashi
Hiroshi
H
Watanabe
Akira
A
Fujita
Teizo
T
Nukiwa
Toshihiro
T
D001992:Bronchoalveolar Lavage Fluid; D004797:Enzyme-Linked Immunosorbent Assay; D005838:Genotype; D006801:Humans; D007564:Japan / Q000453:epidemiology; D037601:Mannose-Binding Lectin / Q000235:genetics* / Q000302:isolation & purification; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D012008:Recurrence; D012141:Respiratory Tract Infections / Q000453:epidemiology / Q000235:genetics*; D012189:Retrospective Studies
D037601:Mannose-Binding Lectin