Features of TLR4 and MMP9 gene expression modified with SARS-CoV-2 antigen and benzapyrene in children

Introduction. Exposure to chemical and biological environmental factors is associated with the risk of realizing genetic predisposition to the development of asthenia and cancer-associated diseases, which determines the relevance of the search for genetic indicator markers of early abnormalities in mRNA structure in the context of modern threats and challenges to public health.

The aim of the study: characteristics of the expression of TLR4 and MMP9 genes modified by the SARS-CoV-2 antigen and benz(a)pyrene in children.

Materials and methods. We analyzed the polymorphism of MMP9 Gln279Arg (rs17576), TLR4 A8595G (rs1927911) genes, as well as the relative normalized expression level of MMP9 Hs00234579_m1 (20q13.12), TLR4 Hs00152939_m1 (9q33. 1) in whole blood cell culture both spontaneous and induced by 24 hour incubation with benz(a)pyrene and vaccine antigens (using SARS-CoV-2, 1.0±0.5•1011 particles as an example) in adolescents of 10–16-years.

Results. Benz(a)pyrene was found to have a potentiating effect on MMP9 expression and a suppressive effect on TLR4. The combination of benz(a)pyrene exposure with SARS-CoV-2 vaccine antigens “in vitro” resulted in differently directed effects depending on the genotype (polymorphism) of the genes under study. The ability of benz(a)pyrene and SARS-CoV-2 antigens to modify “in vitro” expression of MMP9, TLR4 candidate genes was shown, which allows considering genes and products of their expression MMP9 Hs00234579_m1 and TLR4 Hs00152939_m1 as indicator genes for early diagnosis of the development of asthenia and oncoproliferative states.

Limitations. Limitations of the study include the limited sample and scope of the pilot study.

Conclusion. The results of experimental studies ”in vitro” showed the ability of benz(a)pyrene and SARS-CoV-2 to modify the expression of genes of matrix metalloproteinase MMP9 Gln279Arg (rs17576) and toll-like receptor TLR4 A8595G (rs1927911), which allows considering transcripts Hs00234579_m1 and Hs00152939_m1 as criteria for the formation of asthenia in the course of viral infections (SARS-CoV-2) due to activation of the enzyme that destroys the extracellular matrix for AA wild-type and AG heterozygous genotype of the MMP9 Gln279Arg gene. In the case of heterozygous AG genotype of TLR4 A8595G gene, the combination of benz(a)pyrene and SARS-CoV-2 (26 serotype) leads to the formation of immunosuppression, which phenotypically may be accompanied by the development of oncoproliferative processes. MMP9 Hs00234579_m1 and TLR4 Hs00152939_m1 transcripts are recommended as markers of early disorders associated with SARS-CoV-2+benz(a)pyrene exposure.

Compliance with ethical standards. The study was performed in compliance with the ethical requirements of the WMA Declaration of Helsinki, 2000 and the protocol of the Council of Europe Convention on Human Rights and Biomedicine, 1999. The study was approved by the LEC of the Federal Scientific Center for Medical and Preventive Technologies for Population Health Risk Management of the Federal Service for Supervision of Consumer Rights Protection and Human Welfare (Protocol No. 23 of 20.12.2021). Informed consent was obtained for the study participants.

Contribution:
Zaitseva N.V., Dolgikh O.V., Letyushev A.N. — concept and design of the study, writing and editing of the text;
Kazakova O.A. — collection and processing of material, statistical processing, writing and editing of the text;
Ganich T.S. — collection and processing of material.
All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version.

Conflict of interest. The authors declare no conflict of interest.

Acknowledgement. The study had no sponsorship.

Received: April 4, 2024 / Revised: April 25, 2024 / Accepted: June 19, 2024 / Published: July 17, 2024