GAS-Luc Reporter Cell Line - THP1

THP-1 is a human monocytic leukemia cell line established from the peripheral blood of a one-year-old boy with acute monocytic leukemia at relapse. The cells grow predominantly in suspension and are widely used to investigate monocyte and macrophage biology, innate immune signaling and myeloid-cell differentiation. The GAS-Luc Reporter Cell Line - THP1 is an engineered derivative in which luciferase expression is controlled by a gamma-activated sequence (GAS)-responsive regulatory element. In the canonical type II interferon pathway, interferon-γ binds its receptor and activates JAK1 and JAK2, leading to STAT1 phosphorylation, homodimerization and binding to GAS elements. This transcriptional response drives luciferase production, which can be quantified after addition of a compatible substrate. The resulting luminescent signal provides a convenient surrogate for GAS-dependent JAK–STAT activity.

This reporter line is designed for quantitative analysis of interferon-mediated immune signaling in a human monocyte-like background. It can be used to characterize responses to interferon-γ and other stimuli capable of activating GAS-dependent transcription, as well as to evaluate pathway inhibition by JAK inhibitors, STAT1-directed compounds, receptor-blocking agents or neutralizing antibodies. Its luminescent readout is readily adaptable to multiwell assays, supporting concentration–response analysis, compound screening, mechanism-of-action studies and potency testing of immunomodulatory candidates. The model may also be incorporated into co-culture experiments or used to test conditioned media from immune cells, engineered cell therapies or tumor–immune systems for factors that activate the interferon response. Because cytotoxicity or altered cell number can change the reporter signal independently of pathway activity, parallel viability measurements and unstimulated controls are essential.