A recent first-in-human clinical trial demonstrated that survival in glioblastoma (GBM) patients following rQNestin34.5v.2 oncolytic virus treatment was associated with immune activation signatures. This study was registered at ClinicalTrials.gov (NCT03152318). Here, we provide in situ evidence of ongoing T cell-mediated cytotoxicity against tumor cells at late time points following single treatment, with deep and persistent T cell infiltration into tumor regions. Shorter distances between cleaved caspase-3+ tumor cells and granzyme B+ T cells were associated with longer progression-free survival following treatment. Pre-existing tumor-infiltrating T cells expanded locally upon treatment, correlating with longer overall patient survival. T cells with an early activation program closely interacted with tumor cells and were strongly enriched upon treatment. Viral remnants were restricted to necrotic regions, while T cells infiltrated deeply into live tumor regions. These data demonstrate that single oncolytic virus treatment can expand pre-existing T cell clones and trigger persistent T cell-mediated immunity against GBM.

Progressive multiple sclerosis (PMS), which is characterized by relentless disease progression, lacks effective treatment. While recent studies have highlighted the importance of B cells in driving compartmentalized central nervous system (CNS) inflammation in PMS pathogenesis, current B cell depletion therapies, such as CD20 monoclonal antibodies, face challenges in targeting plasma cells within the CNS. Here, we treated five patients with PMS (one primary PMS and four secondary PMS) with anti-B cell maturation antigen (BCMA) chimeric antigen receptor T (CAR-T) cell therapy in an ongoing phase 1 clinical trial (ClinicalTrials.gov: NCT04561557). Only grade 1 cytokine release syndrome was observed, and all grade ≥3 cytopenias occurred within 40 days post-infusion in all five patients. Meanwhile, we detected plasma cell depletion in CNS compartments, prolonged expansion and relieved exhaustion of CAR-T cells in the cerebrospinal fluid, and attenuation of microglial activation. These findings provided insights into the potential application of anti-BCMA CAR-T therapy for advancing clinical management of PMS.

Parkinson's disease (PD) has long been considered an appropriate candidate for cell replacement therapy. We generated high-purity dopaminergic progenitors (A9-DPCs) from human embryonic stem cells and evaluated their safety and exploratory efficacy in a single-center, open-label, dose-escalation phase 1/2a trial (NCT05887466) for PD patients. Twelve patients with moderate-to-severe PD received bilateral putamen transplantation of low-dose (3.15 million cells; n = 6) or high-dose (6.30 million cells; n = 6) A9-DPC with immunosuppression. No dose-limiting toxicities or graft-related adverse events were observed. At 12 months, off-medication Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS) part III scores and Hoehn and Yahr stage improved, with greater motor improvements in the high-dose group. Dopamine transporter positron emission tomography (PET) imaging showed increased posterior putamen uptake with greater uptake in the high-dose group after transplantation, supporting graft survival. These findings indicate that bilateral transplantation of A9-DPC is safe and may improve parkinsonian motor symptoms in patients with PD.

Despite the success of autologous chimeric antigen receptor (CAR)-T cell therapy, achieving persistence and avoiding rejection in allogeneic settings remains challenging. We showed that signal peptide peptidase-like 3 (SPPL3) deletion enabled glycan-mediated immune evasion in primary T cells. SPPL3 deletion modified glycan profiles on T cells, restricted ligand accessibility, and reduced allogeneic immunity without compromising the functionality of anti-CD19 CAR molecules. In a phase I clinical trial, SPPL3-null, T cell receptor (TCR)-deficient anti-CD19 allogeneic CAR-T cells reached the safety primary endpoint, with grade 3 or higher cytokine release syndrome (CRS) observed in 3 out of 9 patients with relapsed/refractory B cell non-Hodgkin lymphoma (B-NHL) (ClinicalTrials.gov: NCT06014073). Reverse translational research highlighted the pivotal role of TCR in sustaining T cell persistence. We therefore evaluated the safety of SPPL3-null, TCR-sufficient CAR-T therapy on three patients with lymphoma or leukemia for compassionate care and observed no clinical signs of graft-versus-host disease. Our findings suggest glycan shielding by SPPL3 deletion is a promising direction for optimizing universal CAR-T therapies.

Personalized neoantigen-targeting vaccines have demonstrated great promise; however, improved immunogenicity is still needed. Since antigen availability and effective T cell priming are critical for maximal immunogenicity, we tested a synthetic long peptide vaccine formulated with Montanide, poly-ICLC, and locally administered ipilimumab in addition to systemic nivolumab in 10 patients with melanoma. These personalized vaccines generated de novo ex vivo T cell responses against the majority of immunizing neoepitopes in all 9 fully vaccinated patients and ex vivo CD8+ T cell responses in 6 of 9. Vaccination induced hundreds of circulating and intratumoral T cell receptor (TCR) clonotypes that were distinct from those arising after PD-1 inhibition. By linking the vaccine neoantigen specificity of T cell clonotypes with single-cell phenotypes in tumors, we demonstrate remodeling of the intratumoral T cell repertoire following vaccination. These observations show that multi-pronged immune adjuvanticity can boost T cell responses to neoantigen-targeting vaccines.

Industrialization adversely affects the gut microbiome and predisposes individuals to chronic non-communicable diseases. We tested a microbiome restoration strategy comprising a diet that recapitulated key characteristics of non-industrialized dietary patterns (restore diet) and a bacterium rarely found in industrialized microbiomes (Limosilactobacillus reuteri) in a randomized controlled feeding trial in healthy Canadian adults. The restore diet, despite reducing gut microbiome diversity, enhanced the persistence of L. reuteri strain from rural Papua New Guinea (PB-W1) and redressed several microbiome features altered by industrialization. The diet also beneficially altered microbiota-derived plasma metabolites implicated in the etiology of chronic non-communicable diseases. Considerable cardiometabolic benefits were observed independently of L. reuteri administration, several of which could be accurately predicted by baseline and diet-responsive microbiome features. The findings suggest that a dietary intervention targeted toward restoring the gut microbiome can improve host-microbiome interactions that likely underpin chronic pathologies, which can guide dietary recommendations and the development of therapeutic and nutritional strategies.

Intermittent fasting has gained global popularity for its potential health benefits, although its impact on somatic stem cells and tissue biology remains elusive. Here, we report that commonly used intermittent fasting regimens inhibit hair follicle regeneration by selectively inducing apoptosis in activated hair follicle stem cells (HFSCs). This effect is independent of calorie reduction, circadian rhythm alterations, or the mTORC1 cellular nutrient-sensing mechanism. Instead, fasting activates crosstalk between adrenal glands and dermal adipocytes in the skin, triggering the rapid release of free fatty acids into the niche, which in turn disrupts the normal metabolism of HFSCs and elevates their cellular reactive oxygen species levels, causing oxidative damage and apoptosis. A randomized clinical trial (NCT05800730) indicates that intermittent fasting inhibits human hair growth. Our study uncovers an inhibitory effect of intermittent fasting on tissue regeneration and identifies interorgan communication that eliminates activated HFSCs and halts tissue regeneration during periods of unstable nutrient supply.

We report the 1-year results from one patient as the preliminary analysis of a first-in-human phase I clinical trial (ChiCTR2300072200) assessing the feasibility of autologous transplantation of chemically induced pluripotent stem-cell-derived islets (CiPSC islets) beneath the abdominal anterior rectus sheath for type 1 diabetes treatment. The patient achieved sustained insulin independence starting 75 days post-transplantation. The patient's time-in-target glycemic range increased from a baseline value of 43.18% to 96.21% by month 4 post-transplantation, accompanied by a decrease in glycated hemoglobin, an indicator of long-term systemic glucose levels at a non-diabetic level. Thereafter, the patient presented a state of stable glycemic control, with time-in-target glycemic range at >98% and glycated hemoglobin at around 5%. At 1 year, the clinical data met all study endpoints with no indication of transplant-related abnormalities. Promising results from this patient suggest that further clinical studies assessing CiPSC-islet transplantation in type 1 diabetes are warranted.

Relatlimab (rela; anti-LAG-3) plus nivolumab (nivo; anti-PD-1) is safe and effective for treatment of advanced melanoma. We designed a trial (NCT03743766) where advanced melanoma patients received rela, nivo, or rela+nivo to interrogate the immunologic mechanisms of rela+nivo. Analysis of biospecimens from this ongoing trial demonstrated that rela+nivo led to enhanced capacity for CD8+ T cell receptor signaling and altered CD8+ T cell differentiation, leading to heightened cytotoxicity despite the retention of an exhaustion profile. Co-expression of cytotoxic and exhaustion signatures was driven by PRDM1, BATF, ETV7, and TOX. Effector function was upregulated in clonally expanded CD8+ T cells that emerged after rela+nivo. A rela+nivo intratumoral CD8+ T cell signature was associated with a favorable prognosis. This intratumoral rela+nivo signature was validated in peripheral blood as an elevated frequency of CD38+TIM3+CD8+ T cells. Overall, we demonstrated that cytotoxicity can be enhanced despite the retention of exhaustion signatures, which will inform future therapeutic strategies.

Allogeneic chimeric antigen receptor (CAR)-T cells hold great promise for expanding the accessibility of CAR-T therapy, whereas the risks of allograft rejection have hampered its application. Here, we genetically engineered healthy-donor-derived, CD19-targeting CAR-T cells using CRISPR-Cas9 to address the issue of immune rejection and treated one patient with refractory immune-mediated necrotizing myopathy and two patients with diffuse cutaneous systemic sclerosis with these cells. This study was registered at ClinicalTrials.gov (NCT05859997). The infused cells persisted for over 3 months, achieving complete B cell depletion within 2 weeks of treatment. During the 6-month follow-up, we observed deep remission without cytokine release syndrome or other serious adverse events in all three patients, primarily shown by the significant improvement in the clinical response index scores for the two diseases, respectively, and supported by the observations of reversal of inflammation and fibrosis. Our results demonstrate the high safety and promising immune modulatory effect of the off-the-shelf CAR-T cells in treating severe refractory autoimmune diseases.

Homologous recombination deficiency (HRD) is prevalent in cancer, sensitizing tumor cells to poly (ADP-ribose) polymerase (PARP) inhibition. However, the impact of HRD and related therapies on the tumor microenvironment (TME) remains elusive. Our study generates single-cell gene expression and T cell receptor profiles, along with validatory multimodal datasets from >100 high-grade serous ovarian cancer (HGSOC) samples, primarily from a phase II clinical trial (NCT04507841). Neoadjuvant monotherapy with the PARP inhibitor (PARPi) niraparib achieves impressive 62.5% and 73.6% response rates per RECIST v.1.1 and GCIG CA125, respectively. We identify effector regulatory T cells (eTregs) as key responders to HRD and neoadjuvant therapies, co-occurring with other tumor-reactive T cells, particularly terminally exhausted CD8+ T cells (Tex). TME-wide interferon signaling correlates with cancer cells upregulating MHC class II and co-inhibitory ligands, potentially driving Treg and Tex fates. Depleting eTregs in HRD mouse models, with or without PARP inhibition, significantly suppresses tumor growth without observable toxicities, underscoring the potential of eTreg-focused therapeutics for HGSOC and other HRD-related tumors.

Diminished hepatocyte regeneration is a key feature of acute and chronic liver diseases and after extended liver resections, resulting in the inability to maintain or restore a sufficient functional liver mass. Therapies to restore hepatocyte regeneration are lacking, making liver transplantation the only curative option for end-stage liver disease. Here, we report on the structure-based development and characterization (nuclear magnetic resonance [NMR] spectroscopy) of first-in-class small molecule inhibitors of the dual-specificity kinase MKK4 (MKK4i). MKK4i increased liver regeneration upon hepatectomy in murine and porcine models, allowed for survival of pigs in a lethal 85% hepatectomy model, and showed antisteatotic and antifibrotic effects in liver disease mouse models. A first-in-human phase I trial (European Union Drug Regulating Authorities Clinical Trials [EudraCT] 2021-000193-28) with the clinical candidate HRX215 was conducted and revealed excellent safety and pharmacokinetics. Clinical trials to probe HRX215 for prevention/treatment of liver failure after extensive oncological liver resections or after transplantation of small grafts are warranted.

CD4+ T cells with latent HIV-1 infection persist despite treatment with antiretroviral agents and represent the main barrier to a cure of HIV-1 infection. Pharmacological disruption of viral latency may expose HIV-1-infected cells to host immune activity, but the clinical efficacy of latency-reversing agents for reducing HIV-1 persistence remains to be proven. Here, we show in a randomized-controlled human clinical trial that the histone deacetylase inhibitor panobinostat, when administered in combination with pegylated interferon-α2a, induces a structural transformation of the HIV-1 reservoir cell pool, characterized by a disproportionate overrepresentation of HIV-1 proviruses integrated in ZNF genes and in chromatin regions with reduced H3K27ac marks, the molecular target sites for panobinostat. By contrast, proviruses near H3K27ac marks were actively selected against, likely due to increased susceptibility to panobinostat. These data suggest that latency-reversing treatment can increase the immunological vulnerability of HIV-1 reservoir cells and accelerate the selection of epigenetically privileged HIV-1 proviruses.