The Journal of Experimental Medicine

The STING pathway is increasingly recognized as a key regulator of neuroinflammation in neurodegenerative disease, but its role in noninflammatory conditions remains unclear. We generated a postnatal inducible whole-body Ngly1 knockout mouse (iNgly1−/−) to model NGLY1 deficiency, an early-onset neurodegenerative disorder. iNgly1−/− mice exhibit progressive motor deficits, Purkinje cell loss, and shortened lifespan without evidence of gliosis or immune activation. Cell type–specific deletion of Ngly1 in Purkinje cells or microglia failed to induce disease, suggesting multiple cell-intrinsic and cell-extrinsic signals are required. Genetic ablation of Sting1 in iNgly1−/− mice rescues Purkinje cell loss, improves motor function, and extends lifespan. Single-nucleus RNA sequencing reveals proteostasis disruption in Purkinje cells, altered cerebellar granule cell subpopulations, and STING-dependent suppression of cholesterol biosynthesis in glia. Pharmacological inhibition of STING with an orally bioactive antagonist, VS-X4, significantly mitigates neuropathology and motor disease. These findings identify STING as a key mediator of neuropathology in NGLY1 deficiency and implicate a role of STING in noninflammatory neurological disease.

doi: 10.1084/jem.20250161pmid: 40736456

Pulmonary Mycobacterium tuberculosis (Mtb) infection results in a variety of heterogeneous lesion structures, from necrotic granulomas to alveolitis, but the mechanisms regulating their development remain unclear. Using a mouse model of concomitant immunity and subsequent aerosol infection, we demonstrate that counter regulation between neutrophils and CD4 T cells occurs very early during infection and governs these distinct pathologies. In primary Mtb infection, a dysregulated feed-forward circuit of neutrophil recruitment occurs, in which neutrophils hinder CD4 T cell interactions with infected macrophages, cause granuloma necrosis, and establish a replicative niche that drives a two-log increase in lung bacterial burden. Conversely, the rapid recruitment and activation of T cells due to concomitant immunity promotes local macrophage activation and dampens detrimental neutrophil responses. Together, these studies uncover fundamental determinants of tuberculosis lung pathology, which have important implications for new strategies to prevent or treat tuberculosis.

To explore the use of human B cell receptor (BCR) knock-in mice for broadening antibody responses, we diversified CR3022, a monoclonal antibody (mAb) originally identified in a 2003 severe acute respiratory syndrome coronavirus (SARS-CoV) convalescent patient. This mAb targets a conserved epitope on the coronavirus receptor-binding domain (RBD). We took advantage of high- and low-affinity CR3022 BCR knock-in mice and immunized them with SARS-CoV-2 Wuhan RBD trimers to expand the breadth of these antibodies toward this virus. The resulting antibodies retained the ability to neutralize SARS-CoV and exhibited enhanced affinity and neutralization against the SARS-CoV-2 WA1/2020 strain, as well as the Delta (B.1.617.2) and Omicron KP.3 variants. They also showed broadened reactivity to two bat coronaviruses: WIV1 and, to a lesser potency, BtKY72. Structural analysis revealed key mutations that enhanced binding and neutralization, highlighting the importance of epitope accessibility and variant-specific conformations in antibody diversification. These findings demonstrate that human BCR-expressing mouse models can generate effective antibodies with broad neutralizing activity against viral epitopes.

doi: 10.1084/jem.20230542pmid: 40705010

Although PD-1 inhibitors are FDA-approved for over 25 different cancers, the mechanisms contributing to response remain incompletely understood. To investigate how PD-1–deleted CD8+ T cells influence PD-1–expressing CD8+ T cells in the same tumor microenvironment, we developed an inducible PD-1 knockout (KO) model in which PD-1 is deleted on ∼50% of cells. PD-1 deletion beginning at day 7 after implantation of MC38 tumor cells led to robust tumor control. Remarkably, PD-1–expressing CD8+ T cells in the tumor had increased functionality similar to PD-1 KO CD8+ T cells. Using single-cell RNA-seq and TCR-seq, we found that the major transcriptional changes following PD-1 deletion were shared by PD-1 KO and PD-1–expressing CD8+ T cells, although PD-1 KO clones preferentially expanded. These data suggest PD-1 inhibitors not only exert cell-intrinsic effects but also may promote increased T cell function through non–cell-autonomous mechanisms, which has important implications for design of PD-1–based cancer immunotherapies.

The World Health Organization (WHO) recently recommended the programmatic use of the R21/Matrix-M vaccine for Plasmodium falciparum malaria prevention in children living in malaria-endemic areas. To determine its effects on humoral immunity, we conducted a proteomic analysis of polyclonal IgG antibodies directed against the NANP tetrapeptide of the circumsporozoite protein (CSP), which comprises the vaccine’s core immunogen. In 10 malaria-naïve adult volunteers, R21/Matrix-M induced polarized IgG anti-NANP repertoires, heavily skewed for IGHV3-30/3-33 genes bearing minimal somatic mutation, which remained static in composition following a controlled human malaria infection challenge. Notably, these vaccine-generated antibodies cross-reacted with another protective CSP epitope, the N-terminal junction region, despite its absence from the R21 construct. NANP-specific IGHV3-30/3-33 mAbs mined from polyclonal IgG repertoires blocked sporozoite invasion in vitro and prevented parasitemia in vivo. Overall, R21/Matrix-M elicits polarized, minimally mutated, polyclonal IgG responses that can target multiple protective CSP epitopes, offering molecular insight into the serological basis for its demonstrated efficacy against P. falciparum malaria.