Low ficolin-2 levels in common variable immunodeficiency patients with bronchiectasis. (2nd January 2015)

• Record Type: Journal Article
• Authors: Metzger, M-L; Michelfelder, I; Goldacker, S; Melkaoui, K; Litzman, J; Guzman, D; Grimbacher, B; Salzer, U
• Is Part Of: Clinical and experimental immunology. Volume 179:Number 2(2015:Feb.)
• Page Start: 256
• Page End: 264
• Publication Date: 2015-01-02
• Subjects: complement -- CVID -- ficolin-2 -- ficolin-3 -- lectin pathway; Immunopathology -- Periodicals; 616.079
• DOI: 10.1111/cei.12459
• Languages: English
• ISSNs: 0009-9104

Abstract

Summary: Common variable immunodeficiency (CVID) encompasses a heterogeneous group of antibody deficiencies characterized by susceptibility to recurrent infections and sequelae, including bronchiectasis. We investigated the relevance of the lectin complement pathway in CVID patients by analysing ficolin-2 and ficolin-3 serum levels and genotyping single nucleotide polymorphisms (SNPs) in the FCN2 and FCN3 genes. Our results show that ficolin-2 levels in CVID patients are significantly lower ( P < 0·0001) than in controls. The lowest ficolin-2 levels are found in CVID patients with bronchiectasis ( P = 0·0004) and autoimmunity ( P = 0·04). Although serum levels of ficolin-3 were similar in CVID patients and controls, CVID patients with bronchiectasis again showed lower levels when compared to controls ( P = 0·0001). Analysis of single nucleotide polymorphisms in the FCN2 gene confirmed known influences on ficolin-2 serum levels, but did not support a genetic basis for the observed ficolin-2 deficiency in CVID. We found that CVID patients with bronchiectasis have very low levels of ficolin-2. The reason for the deficiency of ficolin-2 in CVID and any possible causal relationship is currently unknown. However, as bronchiectasis is a very important factor for morbidity and mortality in CVID, ficolin-2 could also serve as biomarker for monitoring disease complications such as bronchiectasis.