Proinflammatory cytokine genes and their polymorphic variants: clinical and laboratory profiles in the Federal Firefighting Service employees of the EMERCOM of Russia
Authors: Neronova E. G. , Bychkova N. V. , Kalashnikova A. A. , Makarova N. V. 
Published: January 2025

Relevance. Genetic determinants of multifactorial diseases are critical for assessing the risk of genetic diseases and their prevention, especially among the workforce exposed to industry-related dangerous and aggressive occupational factors. Firefighters perform combat service duties in extremely unfavorable industrial environments associated with occupational diseases. Respiratory diseases are among the pathologies with highest incidence rates in firefighters. In addition to environmental factors, the development of these diseases (especially bronchial asthma and chronic obstructive pulmonary disease) is largely driven by impaired immune system – one of the three critical regulatory systems involved in pathogenetic mechanisms of various diseases, including inflammatory diseases. Polymorphic gene variants of inflammatory mediators – in particular cytokine genes and their receptors – mediate the immune system activity and can impact its functionality, susceptibility, or resistance to disease development.

The objective is to analyze how interleukin 1β, 4, 6, 13, TNF and interleukin 6 receptor genes, as well as their polymorphic variants are associated with respiratory diseases and changes in the biomarker profiles showing immune response intensity in the employees of the Federal Firefighting Service of the EMERCOM of Russia.

 Methodology. Molecular genetic profiling and immunology tests were performed in 70 employees of the Federal Firefighting Service of the EMERCOM of Russia to analyze proinflammatory cytokine genes and their polymorphic variants. Real-timePCR was used to analyze the interleukin 1β, 4, 6, 13, TNF and interleukin-6 receptor genes and their polymorphic variants. Immunological examination evaluated the blood monocyte subpopulations and relative count of type 2 T-helper cells; flowcytometry and immunochemiluminescence assays were used to evaluate immune response biomarkers in peripheral blood and total immunoglobulin E (IgE) respectively.

Results and discussion. The analysis provides evidence that minor alleles of most polymorphic cytokine genes are associated with a proinflammatory phenotype, which is especially apparent for genotypes comprising several minor alleles. Allele A at rs1 800 629 polymorphic TNF gene exposed a direct correlation with respiratory diseases, as well as with increased monocyte differentiation. Allele T of IL4 rs2243250 gene and allele A of IL1β rs16944 gene were associated with increased proinflammatory monocyte count. Elevated count of type 2 T-helper mediators of humoral response, especially of allergicorigin, was observed in individuals with C/C IL6 rs1 800 795 and G/G IL1β rs16944 genotype.

Conclusion. The obtained results suggest that evaluation of cytokine gene polymorphic variants is a promising strategy to predict the risk of respiratory diseases in firefighters. Prompt assessment of genetic predisposition to a proinflammatory phenotype paves the way towards prevention and early detection of inflammatory diseases in this cohort of workers.