Editor’s summary
Autoantibodies generated against extracellular antigens, including cytokines, can lead to immune dysregulation and secondary immunodeficiency. For example, patients with neutralizing autoantibodies against interferon-γ (IFN-γ) (nAIGAs) display increased susceptibility to opportunistic pathogens such as nontuberculous mycobacteria. To selectively target nAIGA-producing B cells, Peng
et al. engineered chimeric autoantibody (CAAR) T cells bearing a truncated IFN-γ mutant bait. IFN-γ CAAR T cells eliminated nAIGA-expressing target cells in mice and B cells from patients with nAIGAs while minimizing off-target toxicity. These findings identify a potential therapeutic approach for treating patients with nAIGAs and possibly other anticytokine autoantibodies. —Claire Olingy
Abstract
Neutralizing anti–interferon-γ (IFN-γ) autoantibodies (nAIGAs) impair IFN-γ–mediated immunity, predisposing patients with nAIGAs to infection by nontuberculous mycobacteria,
Talaromyces marneffei, and other intracellular pathogens. Current clinical management relies on continuous antimicrobial therapy, with no treatment offering sustained benefits. Here, we developed human chimeric autoantibody receptor (CAAR) T cells targeting autoreactive B cells expressing nAIGA B cell receptors (BCRs) using an IFN-γ receptor–irresponsive IFN-γ variant as bait. By exploiting a mouse model of nAIGA BCR-expressing B cell leukemia, we found that IFN-γ CAAR T cells lack off-target toxicity, including IFN-γ receptor cross-reactive toxicity and Fc-redirected toxicity. IFN-γ CAAR T cells substantially reduced circulating AIGAs secreted from target cells in vivo. Further, IFN-γ CAAR T cells effectively eliminated autoreactive B cells in ex vivo cultures of peripheral blood mononuclear cells from patients with nAIGAs. Together, these results demonstrate that IFN-γ CAAR T cells may be a promising strategy to ameliorate nAIGA-associated infections by eliminating autoreactive B cells.
