Free Kappa Light Chain in Bronchial Asthma; Review Article

Abstract

Background: Polyclonal immunoglobulin free light chains (FLC) were found elevated in various biological fluids in a number of chronic inflammatory diseases. Urinary FLC concentrations, which correlate with the degree of systemic inflammation, are elevated in patients with chronic inflammatory rheumatic disease; serum FLC concentrations, correlating with disease activity, were found elevated in patients with systemic lupus erythematosus (Bramlage et al., 2016).  A previous study showed elevated serum κ, but not λ, Ig FLCs in both atopic and nonatopic asthma patients compared with healthy control subjects. FLC are active ubiquitous molecules that are able to trigger and/or participate in inflammatory processes through the antigen-specific activation of mast cells.

Aim: To compare FLC-k serum level in both asthma patients and healthy control.  To compare FLC-k serum levels in mild to moderate and severe asthma patients. To compare FLC-k serum levels in atopic and non atopic asthma patients. To assess diagnostic value of FLC-k in asthma patients.

Conclusion: Serum FLC-κ levels were significantly higher in patients with bronchial asthma than in healthy controls. Furthermore, serum FLC-κ levels increased progressively with increasing asthma severity, being highest among patients with severe asthma. Moreover, ROC curve analysis demonstrated excellent diagnostic performance of serum FLC-κ levels. All these findings suggest that serum FLC-κ may represent a promising biomarker for diagnosis and assessment of asthma and may reflect the inflammatory burden and severity of the disease.