Study the association between interleukin-4 polymorphism and specific Chlamydia Pneumoniae Immunoglobulin E in asthmatic children

Background: Asthma is a chronic disorder caused by complex interactions between genetic and environmental influences. Objective: Investigate the possible correlation between interleukin-4 (IL-4) gene polymorphisms and development of specific Chlamydia pneumoniae immunoglobulin (Ig) E levels. Materials and Methods: A total of 87 children, including 57 males and 30 females with asthma with ages between 1 and 16 years, attended the Respiratory Clinic at Karbala Pediatric Hospital, with a nonasthmatic children group which have the same age and gender. Restriction fragment length polymerase chain reaction was performed to determine IL-4 C-589T genetic polymorphisms. Total IgE level, C. pneumoniae IgG, and C. pneumoniae IgE antibodies were measured using the commercial quantitative enzyme-linked immunosorbent assay kits. Results: C. pneumoniae IgG and IgE antibodies were significantly increased in patients as compared with controls (P < 0.001 and P = 0.024, respectively). The CT genotype of IL-4 C-589T polymorphism was associated with asthmatic children (P < 0.01). A high C. pneumoniae IgE levels were found to be associated with CC genotypes (P = 0.01). On the other hand, there were no significant differences in serum C. pneumoniae IgG levels depending on different IL-4 C589T genotypes (P = 0.662). Conclusion: The development of C. pneumoniae IgE antibody in asthmatic children did not depend on IL-4 polymorphism.