Anti-BPIFA1/SPLUNC1: a new autoantibody prevalent in patients with endstage cystic fibrosis

J Cyst Fibros. 2014 May;13(3):281-8. doi: 10.1016/j.jcf.2013.10.005. Epub 2013 Oct 23.

Abstract

Background: Bactericidal/permeability increasing protein fold containing family A (BPIFA) 1, is a secreted protein of the upper airways that shares structural homology with BPI and exhibits comparable antimicrobial capacities. We hypothesized that CF patients have circulating IgG or IgA anti-BPIFA1 autoantibodies, similarly as reported for BPI autoantibodies.

Methods: We analyzed pre- and post-transplantation sera from 67 endstage lung disease patients who underwent lung transplantation (LTx) because of COPD (n=27), CF (n=25), and ILD (n=15).

Results: Anti-BPIFA1 (48%) and anti-BPI (92%) were elevated in CF patients compared to healthy controls, with anti-BPIFA1 IgG isotype being most prevalent, whereas anti-BPI is of the IgA isotype. Levels of anti-BPI autoantibodies significantly declined post-LTx, whereas anti-BPIFA1 did not. No relation was found between autoantibodies against BPIFA1 and BPI.

Conclusion: Our results indicate that BPIFA1 is a novel target for autoantibodies in CF. The function of these autoantibodies needed to be investigated in future studies.

Keywords: Autoantibodies; BPI; BPIFA1; Cystic fibrosis; Lung transplantation.

MeSH terms

  • Adolescent
  • Adult
  • Autoantibodies / immunology*
  • Cohort Studies
  • Cystic Fibrosis / epidemiology
  • Cystic Fibrosis / immunology*
  • Cystic Fibrosis / surgery
  • Female
  • Glycoproteins / immunology*
  • Homeodomain Proteins / immunology
  • Humans
  • Immunoglobulin A / immunology
  • Immunoglobulin G / immunology
  • Lung Transplantation
  • Male
  • Middle Aged
  • Phosphoproteins / immunology*
  • Pulmonary Disease, Chronic Obstructive / epidemiology
  • Pulmonary Disease, Chronic Obstructive / immunology*
  • Pulmonary Disease, Chronic Obstructive / surgery
  • Rheumatoid Factor / immunology
  • Seroepidemiologic Studies
  • Transcription Factors / immunology
  • Young Adult

Substances

  • Autoantibodies
  • BPIFA1 protein, human
  • DLX4 protein, human
  • Glycoproteins
  • Homeodomain Proteins
  • Immunoglobulin A
  • Immunoglobulin G
  • Phosphoproteins
  • Transcription Factors
  • Rheumatoid Factor