Orthogonal interleukin-9 receptor (oIL-9R) (oIL-9R)

The orthogonal interleukin-9 receptor (oIL-9R) is a synthetic signaling platform designed to provide selective support to engineered T cells, such as pmel-1 T cells, in the tumor microenvironment. By mutating the binding interface of the wild-type IL-9 receptor, researchers created a version that no longer responds to natural IL-9 but retains high affinity for a complementary, mutated "orthogonal" IL-9 (oIL-9) ligand (Kalisz et al., Nature, 2022). This system allows for the precise control of T cell expansion and function through the JAK-STAT signaling pathway—specifically STAT1, STAT3, and STAT5—without the pleiotropic side effects or systemic toxicity typically associated with high-dose cytokine therapy (Sockolosky et al., Science, 2018). In the context of pmel-1 T cells, which are TCR-transgenic cells specific for the melanoma antigen gp100, the oIL-9R system enhances anti-tumor efficacy and metabolic fitness, enabling these cells to overcome the immunosuppressive nature of solid tumors (Kalisz et al., Nature, 2022). This technology represents a significant advancement in adoptive cell therapy, offering a "remote control" mechanism to boost therapeutic cells while sparing endogenous immune populations. The use of IL-9 signaling is particularly advantageous as it promotes a stem-like memory phenotype in T cells, which is associated with superior persistence and long-term anti-tumor immunity (Kalisz et al., Nature, 2022).

Other names

oIL-9ROrthogonal IL-9 receptorSynthetic interleukin-9 receptorMutated interleukin-9 receptor

Selective activation of the JAK-STAT signaling pathway (specifically STAT1, STAT3, and STAT5) in engineered T cells through a synthetic ligand-receptor pair that avoids cross-reactivity with endogenous immune components (Kalisz et al., Nature, 2022).