Serum Levels of Leukemia Inhibitory Factor (LIF) in Wheezy Infants and its Relation with Respiratory Syncytial Virus Infection.

Objective: Leukemia inhibitory factor (LIF) is the most pleiotropic member of the interleukin-6 family of cytokines. It utilises a receptor that consists of the LIF receptor ß and gp130 and this receptor complex is also used by ciliary neurotrophic growth factor (CNTF), oncostatin M, cardiotrophin1 (CT1) and cardiotrophin-like cytokine (CLC). Evidence is emerging that LIF may play an important role in airway inflammation. Recurrent wheezing is one of the commonest problems of early childhood and respiratory syncytial virus (RSV) is the most frequent cause of wheezy episodes. Material and Method: The aim of this study was to determine whether LIF has a role in the airway inflammation of wheezy children and its relationship with RSV infection. Results: Serum LIF levels, total IgE levels, RSV-IgM and RSVIgG antibodies were evaluated in wheezy (22F, 18M) and healthy (18F, 20M) infants. RSV-IgM antibodies were detected in 25% of wheezy and 3% of healthy children. RSV-IgG antibodies were detected 35% and 23%, respectively. There was not significant difference in median serum levels of LIF between wheezy and healthy infants. However, median serum LIF level of subjects who were seropositive for RSV-IgM antibodies was significantly higher than those who were seronegative for RSV-IgM antibodies (16 pg/ml vs 10.5 pg/ml; p=0.01). Conclusion: This study suggests that LIF might play a role in early airway inflammation in infants with wheezy RSV infection. [ABSTRACT FROM AUTHOR]