Increased IgG antibody-induced cytotoxicity against airway epithelial cells in patients with nonallergic asthma.
BACKGROUND
IgG autoantibodies to airway epithelial cell proteins have been detected in patients with nonallergic asthma.


OBJECTIVE
To evaluate the functional significance of these autoantibodies, we examined the presence of IgG antibody-induced cytotoxicity against airway epithelial cells (A549) by the microcytotoxicity assay using IgG antibodies purified from patients with nonallergic asthma.


RESULTS
IgG antibody-induced cytotoxicity (expressed as percent cell lysis) was significantly increased in nine patients with nonallergic asthma (mean +/- standard deviation; 30.6 +/- 7.3%) as compared with eight healthy controls (13.9 +/- 5.1%) and nine patients with allergic asthma (20.3 +/- 10.4%; p < 0.05). In addition, IgG antibody-induced cytotoxicity was significantly inhibited when IgG antibodies from patients with nonallergic asthma were pre-incubated with recombinant human airway epithelial cell autoantigens (cytokeratin 18 or alpha-enolase proteins; p < 0.05).


CONCLUSIONS
These results suggest a possible involvement of IgG autoantibody-induced cytotoxicity against airway epithelial cells in the pathogenesis of nonallergic asthma.
Kwon
Byul
B
Department of Allergy and Rheumatology, Ajou University School of Medicine, Suwon, South Korea.
Lee
Hye-Ah
HA
Choi
Gil-Soon
GS
Ye
Young-Min
YM
Nahm
Dong-Ho
DH
Park
Hae-Sim
HS
D000328:Adult; D001249:Asthma / Q000276:immunology*; D001323:Autoantibodies / Q000097:blood / Q000276:immunology*; D001324:Autoantigens / Q000276:immunology*; D003602:Cytotoxicity, Immunologic; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology*; D053538:Keratin-18 / Q000494:pharmacology; D008297:Male; D008875:Middle Aged; D010751:Phosphopyruvate Hydratase / Q000494:pharmacology; D011994:Recombinant Proteins / Q000494:pharmacology; D020545:Respiratory Mucosa / Q000276:immunology*
D001323:Autoantibodies; D001324:Autoantigens; D007074:Immunoglobulin G; D053538:Keratin-18; D011994:Recombinant Proteins; D010751:Phosphopyruvate Hydratase