InVivoMAb anti-human CD28

Hepatocellular carcinoma (HCC) evades anti-PD-1 immunotherapy via an immunosuppressive microenvironment, where lactate links metabolic reprogramming to epigenetic regulation. We analyzed pan-lysine lactylation and H3K18 lactylation (H3K18la) in 89 HCC patient pairs, and validated functional mechanisms using glycolysis inhibition, HCC-CD8+ T cell co-cultures, and rescue assays. In vivo efficacy was assessed in subcutaneous and orthotopic HCC mouse models. H3K18la levels were elevated in HCC, correlating with advanced staging and poor prognosis. Lactate induced H3K18la to transcriptionally upregulate KIF20A, which stabilized the c-Myc/PD-L1 axis and suppressed cytotoxic T cell function. Combined glycolysis inhibition and anti-PD-1 therapy reversed this immunosuppression and synergistically inhibited tumor growth. This study identifies an H3K18la-KIF20A/PD-L1 axis as a key metabolic-epigenetic checkpoint, highlighting glycolysis targeting as a promising strategy to enhance anti-PD-1 responses in HCC.

Immunotherapy has revolutionized cancer treatment, yet many patients show non-sensitivity. Here, we collected treatment-naïve samples from 190 esophageal squamous cell carcinoma (ESCC) patients undergoing anti-programmed death 1 (PD1) immunotherapy for proteome, phosphoproteome, and immunohistochemistry (IHC) analysis. Proteome-based stratification of ESCC identifies three proteomic subtypes (G-I-G-III) related to immunotherapy response and different molecular features, revealing that patients with high mitochondrial complex I protein expression show sensitivity to anti-PD1 immunotherapy. High mitochondrial complex I protein expression of ESCC cells or patient-derived organoids increases sensitivity to CD8 + T cell-mediated killing in the co-culture systems. Phosphoproteomic data analysis reveals YAP1 activation impairs immunotherapy efficacy. Inhibiting YAP1 or increasing mitochondrial complex I levels bolsters immunotherapy effectiveness in ESCC allograft tumors. Finally, we develop a highly accurate predictive model (AUC ≥ 0.90) by the signatures of mitochondrial complex I-mediated anti-tumor immune response and validate it in independent cohorts. This study provides a rich resource for investigating the mechanisms and indicators of immunotherapy in ESCC.

CD4+ regulatory T cells (Treg cells) are essential for immune tolerance1. Peripherally induced Treg cells (pTreg cells) complement thymic Treg cells by broadening Treg cell reactivity in response to a changing antigenic landscape2. Although both TGFβ and IL-2 synergistically promote functional pTreg cell development in vitro3-6, their combined roles in inducing pTreg cell generation in vivo have not been exploited for tolerizing immunotherapy. Here we designed an IL-2-TGFβ 'surrogate' co-agonist by creating a single-chain fusion protein between IL-2 and a low-affinity TGFβ mimic agonist derived from a helminth parasite7. This IL-2-TGFβ surrogate functions as an AND-gated co-agonist and enabled simultaneous cis-activation of IL-2-STAT5 and TGFβ-SMAD2/3 signalling specifically in T cells that express IL-2 receptors. The IL-2-TGFβ surrogate agonist robustly induced antigen-specific, functional and stable pTreg cells in vivo within peripheral lymphoid organs in mice immunized with ovalbumin (OVA) and myelin oligodendrocyte glycoprotein (MOG)35-55. The induced pTreg cells display an effector-like, actively expanding state with high RORγt expression, enabling efficient migration and suppression of intestinal inflammation. Treatment with this agonist effectively quelled immune activation in mouse models of allergen-induced allergic inflammation and self-antigen-driven autoimmune neuroinflammation, suggesting a strategy for the induction of antigen-specific pTreg cells in vivo to establish immune tolerance in inflammatory, allergic and autoimmune diseases.

Inflammatory bowel disease (IBD) is a highly prevalent condition characterized by chronic inflammation present along the gastrointestinal (GI) tract. Mitigation of symptoms is critical to the quality of life of patients. Targeting Mucosal Addressin-Cell Adhesion Molecule 1 (MAdCAM-1), a cell surface antigen predominantly expressed on endothelial cells of venules located in the lamina propria of the small intestine and colon, represents an attractive marker to locally deliver therapeutics that dampen inflammation associated with IBD. As such, mAbs derived from eight hybridoma clones were characterized, shown to bind to human MAdCAM-1 with dissociation constants in the low to sub-nanomolar range and were able to detect human MAdCAM-1 transiently expressed on the surface of cells. Interestingly, only 4 of these antibodies detected MAdCAM-1 on the venules of human small intestinal tissue by immunohistochemistry. Importantly, these 4 antibody clones, 1B10, 11C3, 7A2, and 2F3 behave as strong antagonists, able to block MAdCAM-1 costimulation of primary human CD4+ T cells. These antibodies or related anti hMaDCAM-1 scFv bispecifics may serve as targeted therapeutics to the GI tract for treating IBD.