IFNG

Overview

IFNG encodes interferon gamma (IFN-γ), a key pro-inflammatory cytokine produced primarily by activated T cells and natural killer (NK) cells. It is a central mediator of type 1 immune responses, promoting macrophage activation, antigen presentation, and cytotoxic immune function. In biomedical research, IFNG is widely used as a marker of Th1- and Tc1-biased immunity and is frequently measured as an indicator of vaccine immunogenicity, anti-tumor immune activation, and inflammatory disease activity.

Although IFNG is not a structural cellular component in the classical sense, it is often studied in cellular and tissue contexts because its expression reflects immune-cell activation states and immune microenvironment remodeling. Its signaling is closely linked to pathways involving STAT1, antigen presentation, checkpoint regulation, and inflammatory cytokine networks, including IL-2, IL-6, IL-17A, TNF-α, and GM-CSF. In recent studies, IFNG has been repeatedly used as a readout for immune stimulation or suppression across infections, cancer, autoimmunity, and vaccine development.

Focus of Latest Publications

Recent publications have examined IFNG in several immune and disease contexts, most often as part of inflammatory signaling or immune-response signatures. In a multi-omics aging study, two-sample Mendelian randomization of circulating inflammatory proteins identified IFNG as one of the most robust pro-aging mediators across six aging phenotypes, alongside IL-12B and IL-2. That work further integrated summary-based MR with eQTL, sQTL, pQTL, and mQTL resources to map downstream effector genes for epigenetic age acceleration, supporting a broader role for inflammation-linked pathways in biological aging.

IFNG was also implicated in transplant immunology and tissue engraftment. In paired pre- and post-transplant profiling of human embryonic stem-cell-derived retinal pigment epithelium (hESC-RPE), investigators found a Th1-skewed, IFN-γ-rich immune milieu in blood, aqueous humor, and retinal tissue. They showed that IFN-γ-JAK1 signaling promoted an immunogenic state in hESC-RPE, including increased HLA expression and antigen-presentation features, and that brief ex vivo conditioning with ruxolitinib attenuated this response while preserving epithelial properties. In humanized retinal degeneration models, conditioned grafts had reduced T and NK-cell infiltration, improved survival, and better visual function.

Several cancer-focused studies used IFNG as part of immune signatures or immune-phenotype analyses. In melanoma, IFNG was included in an 8-gene VIP-related prognostic signature with CD28, CD80, CD86, CTLA4, FAS, IL10, and IL12A; the signature was associated with overall survival, immune-cell infiltration, and immune checkpoint expression, and was evaluated alongside in silico drug-sensitivity estimates. In colorectal cancer, IFNG expression was analyzed together with CD274/PD-L1 in relation to immune-cell fractions during multi-omics immunophenotyping, helping define immune subtypes and associated prognostic genes. These studies positioned IFNG as a marker of immune activity within the tumor microenvironment rather than as a direct therapeutic target.

IFNG-driven macrophage activation was also central in granulomatous skin disease. Reanalysis of single-cell RNA-seq data from granuloma annulare and cutaneous sarcoidosis, combined with in vitro experiments, showed that IFN-γ activated macrophages through oxidative phosphorylation and an IFN-γ-induced response network sensitive to electron transport chain inhibition. GBP1 was identified as a central regulator of IFN-γ-mediated macrophage activation, and inhibition of IFN-γ signaling, ETC complexes, or GBP1 reduced granuloma formation in a human in vitro model. metformin, as an ETC complex I inhibitor, suppressed IFN-γ activation and granuloma formation.

In cellular immunotherapy, IFNG was measured as a functional readout of CAR-T activity. In HER2-CAR-T cells engineered to secrete IL-12, IFN-γ production correlated with target-antigen density, and IL-12 secretion enhanced tumor-cell killing in gastric cancer models. Together, these recent studies link IFNG to inflammatory aging, graft immunogenicity, tumor immune profiling, granulomatous inflammation, and engineered T-cell function.