Expression of Toll-like Receptor Genes and Antiviral Cytokines in Macrophage-like Cells in Response to Indole-3-carboxylic Acid Derivative

Ongoing outbreaks and often rapid spread of infections caused by coronaviruses, influenza, Nipah, Dengue, Marburg, monkeypox, and other viruses are a concern for health authorities in most countries. Therefore, the search for and study of new antiviral compounds are in great demand today. Since almost all viruses with pandemic potential have immunotoxic properties of various origins, particular attention is paid to the search and development of immunomodulatory drugs. We have synthesised a new compound related to indole-3-carboxylic acid derivatives (hereinafter referred to as the XXV) that has antiviral and interferon-inducing activity. The purpose of this work is to study the effect of the XXV on the stimulation of the expression of toll-like receptor genes, interferons, and immunoregulatory cytokines in a macrophage-like cell model. In this study, real-time PCR methods were used to obtain data on the transcriptional activity of genes in macrophage-like cells. Stimulation of the genes of toll-like receptors <i>TLR2</i>, <i>TLR3</i>, <i>TLR4</i>, <i>TLR7</i>, <i>TLR8</i>, and <i>TLR9</i> was detected. A high-fold increase in stimulation (from 6.5 to 16,000) of the expression of the <i>TLR3</i> and <i>TLR4</i> genes was detected after 4 h of exposure to the XXV. Increased activity of interferon (<i>IFNA1</i>, <i>IFNA2</i>, <i>IFNB1</i>, <i>IFNK</i>, and <i>IFNλ1</i>) genes with simultaneous stimulation of the expression of interferon receptor (<i>IFNAR1</i> and <i>IFNAR2</i>) genes and signalling molecule (<i>JAK1</i> and <i>ISG15</i>) genes was detected. Increased fold stimulation of the expression of the cytokine genes <i>IL6</i>, <i>TNFA</i>, <i>IL12A</i>, and <i>IL12B</i> was also observed. Thus, it is shown that the XXV is an activator of <i>TLR</i> genes of innate immunity, which trigger signalling mechanisms of pathogen "recognition" and lead to stimulation of the expression of genes of proinflammatory cytokines and interferons.