Autoantibodies against CD80 in patients with COPD

Abstract

Chronic obstructive pulmonary disease (COPD) is an inflammation disorder and possibly an autoimmune disease. The components of the autoimmune response in the circulatory system are of considerable interest to clinicians. Because aberrations of costimulation status have been noted in COPD, the presence of autoantibodies to B7 costimulatory factor CD80 were investigated in a cohort of patients. Recombinant rs1CD80 (lacking the transmembrane domain of CD80) was used for Western blot analysis and ELISA to investigate the presence of autoantibodies in sera of patients with stable COPD and in controls without COPD. Cytokines IL-6 and IL-8 were detected using ELISA. Western blot revealed a specific band reacting to rs1CD80 by diluting sera pool of patients, which indicated the existence of autoantibodies to CD80. The serum level of anti-rs1CD80 was higher in patients with COPD than in controls(P=0.0185) and was positively correlated to the serum level of IL-6 (r=0.797, P<0.001) and IL-8 (r=0.608, P<0.001). There was a tendency that more higher level of anti-rs1CD80, more severe COPD stage. The existence of autoantibodies to costimulatory factor CD80 may suggest a pathogenic role of costimulatory factors in COPD.

<p>Serum Levels of Autoantibodies Against Extracellular Antigens and Neutrophil Granule Proteins Increase in Patients with COPD Compared to Non-COPD Smokers</p>

“…Previously, many autoantibodies such as anti-extracellular matrix proteins, anti-cytokeratins, anti-immune molecules antibodies have been suggested to associate with COPD and some of them have been shown to correlate with disease phenotypes, 19,22,[40][41][42][43] suggesting that those autoantibodies might contribute to the development of the disease. However, such associations have not been confirmed by others 45,[54][55][56][57] and were also not observed in our study using microarray data analysis.…”

“…Since several autoantibodies including those against elastin, aggrecan, cytokeratin 18, cytokeratin 19, CD80, β2-microglobulin and collagen I, II and IV have already been suggested to be upregulated in COPD, 19,22,[40][41][42][43] we evaluated the expression of those autoantibodies in our samples. All those autoantigens were presented on the microarray, but no significant difference was observed for any of those autoantibodies between COPD patients and non-COPD smokers (Supplementary Table 3).…”

Autoantibodies in Chronic Obstructive Pulmonary Disease

“…Notably, according to this study, those autoantibodies are also present in inflammatory lung diseases suggesting that they are not COPD specific. Very recently, Luo et al investigated autoantibodies against a soluble form of CD80 (sCD80), a co-stimulatory molecule for T cell activation, in sera of patients with COPD ( 38 ). They found that serum levels of anti-sCD80 were higher in patients with COPD than in controls and were positively correlated to inflammatory cytokines, e.g., IL-6 and IL-8 ( 38 ).…”

“…Very recently, Luo et al investigated autoantibodies against a soluble form of CD80 (sCD80), a co-stimulatory molecule for T cell activation, in sera of patients with COPD ( 38 ). They found that serum levels of anti-sCD80 were higher in patients with COPD than in controls and were positively correlated to inflammatory cytokines, e.g., IL-6 and IL-8 ( 38 ). Another immune molecule, β2-microglobulin that is a component of MHC class I molecules, has also been identified as an autoantigen in COPD ( 18 ).…”

“…Besides anti-CK-18 and anti-CK-19, two other autoantibodies have been reported to correlate with disease severity in COPD. While the presence of anti-sCD80 antibodies was shown to be associated with a high GOLD stage ( 38 ), autoantibodies against CMP correlated with a high GOLD stage and were inversely correlated with lung function parameters ( 21 ).…”