Biology subjects

Binder, C. J.

Publications and source records attributed to Binder, C. J..

5 recordsLinked to original sources

bioRxiv2026

Targeting IL-2 to inflamed tissues via oxidation-specific epitopes enables third-generation bispecific IL-2 therapeutics

Interleukin-2 (IL-2) is essential for the survival and activation of regulatory T cells (Tregs). Low-dose native IL-2 (IL-2LD) therapy restores immune regulation in vivo and has shown reproducible clinical benefit across multiple autoimmune, inflammatory, and neuroimmune diseases. Attempts to improve IL-2 through engineered variants (muteins) have mainly focused on enhancing Treg selectivity by reducing IL-2 receptor {beta}-chain binding, but this strategy profoundly diminishes biological potency, likely contributing to the limited clinical efficacy of IL-2 muteins. Here, we develop a ''third-generation IL-2'' that combines site-specific targeting and bifunctionality. We generated a bivalent fusion protein linking IL-2 to a single-chain antibody recognizing oxidation-specific epitopes (OSEs), which are abundantly expressed at inflamed sites. Targeting OSEs provides not only site-specific localization, but also true bifunctionality as both anti-OSE antibodies and IL-2LD independently show therapeutic benefit in limiting inflammation. We first show that IL-2IT has bifunctional biological activities in vitro. In vivo, IL-2IT had increased specificity for Treg over Teff activation, which we attribute to a conformation-dependent modulation of IL-2 receptor engagement. Importantly, IL-2IT provided precise delivery to inflamed tissues in models of psoriasis and colitis. Altogether, this resulted in superior therapeutic benefit in multiple clinical settings, including in atherosclerosis models. Thus, our strategy illustrates a generalizable approach to cytokine engineering that preserves native signaling while achieving spatial control. Specifically, our findings validate OSE targeting as an efficient strategy to guide therapeutics to sites of inflammation and establish OSE-IL-2 as a promising bispecific Treg engager for treating inflammation.

immunology↗

bioRxiv2026

Antibody recycling via FcRn drives atherosclerotic plaque vulnerability

Atherosclerotic plaques accumulate low-density lipoprotein (LDL) together with antibodies targeting LDL and its apolipoprotein B (apoB) component. Given the association between IgG and plaque vulnerability, we hypothesized that apoB-specific immune complexes actively promote plaque destabilization. Using immunohistochemistry in carotid endarterectomy specimens, we quantified antibody deposition across morphologically defined plaque regions, and measured apoB reactivity and immune complex levels in matched plaque and plasma samples. IgG deposition was strongly associated with thin fibrous caps, reduced collagen content, and higher overall plaque vulnerability. Symptomatic patients exhibited increased apoB-specific IgG and reduced apoB-IgG immune complexes within plaques, indicating enhanced IgG recycling and heightened inflammatory activity. The neonatal Fc receptor (FcRn) was predominantly expressed by CD163+ macrophages, and mediated antibody recycling, LDL uptake, and production of tumor necrosis factor (TNF) and matrix metalloproteinase-9 (MMP-9) in vitro. Plaque FcRn expression increased with age and correlated with mediators of vulnerability, including collagen-degrading enzymes and pro-inflammatory cytokines. Ex vivo treatment of human plaques with a clinically used FcRn-blocking monoclonal antibody reduced IgG recycling and suppressed TNF and MMP-9 production. These findings identify FcRn-dependent antibody recycling as a contributor to inflammatory plaque vulnerability and highlight FcRn as a potential therapeutic target in atherosclerosis.

immunology↗

bioRxiv2023

TREM2 limits necrotic core formation during atherogenesis by controlling macrophage survival and efferocytosis

Atherosclerosis is a chronic disease of the vascular wall driven by lipid accumulation and inflammation in the intimal layer of arteries [1], [2], and its main complications, myocardial infarction and stroke, are the leading cause of mortality worldwide [3]. Recent studies have identified Triggering receptor expressed on myeloid cells 2 (TREM2), a lipid-sensing receptor regulating several key myeloid cell functions [4], as a highly expressed marker of macrophage foam cells in experimental and human atherosclerosis [5]. However, the function of TREM2 in the development of atherosclerosis is unknown. Here, we show that hematopoietic or global TREM2 deficiency increases necrotic core formation in early experimental atherosclerosis. We further demonstrate that TREM2 is essential for the efferocytosis capacities of macrophages, and to the survival of lipid-laden macrophages, altogether indicating a crucial role of TREM2 in maintaining the balance between foam cell death and their clearance in atherosclerotic lesions, thereby controlling plaque necrosis.

immunology↗

bioRxiv2020

Alternate models of acute dyslipidemia reveal divergent pathways upon atherosclerosis initiation

Atherosclerosis is thought to be initiated by the sub-intimal retention of apolipoprotein-B containing lipoproteins within susceptible sites of the vasculature. Understanding this initiation is not possible with current legacy mouse models of atherosclerosis. We created two mouse strains of inducible hypercholesterolemia based on conditional loss of apolipoprotein E or through inducible expression of a gain-of-function proprotein convertase subtilisin/kexin type 9 D374Y mutation. Both strains rapidly broke plasma-lipid homeostasis and converted to a state of atherogenic dyslipidemia, resulting in overt aortic-accumulation of lipoproteins within 10 days. RNA-sequencing revealed that the vascular response is completely dependent on the route taken to dyslipidemia, which nevertheless implicates known pathogenic pathways in the aetiology of atherosclerosis, and further implicates APOE as an inhibitor of inflammation. As atherosclerosis develops, a convergence of common mechanistic processes emerge in both strains with significant involvement of the immune system, and targeting of CD8 T cells can regulate a conserved aortic response. Our results define atherosclerosis initiation as highly heterogeneous process and identify multiple potential therapeutic targets that may influence disease onset.

physiology↗

bioRxiv2020

SIRPalpha on mouse B1 cells restricts lymphoid tissue migration and natural antibody production

The inhibitory immunoreceptor SIRP is expressed on myeloid and neuronal cells and interacts with the broadly expressed CD47. CD47-SIRP interactions form an innate immune checkpoint and its targeting has shown promising results in cancer patients. Here, we report expression of SIRP on B1 lymphocytes, a non-conventional subpopulation of murine B cells responsible for the production of natural antibodies. Mice defective in SIRP signaling (SIRP{Delta}CYT mice) displayed an enhanced CD11b/CD18 integrin-dependent B1 cell migration from the peritoneal cavity to the spleen, local B1 cell accumulation, and enhanced circulating natural antibody levels, which was further amplified upon immunization with T-independent type 2 antigen. As natural antibodies are atheroprotective we investigated the involvement of SIRP signaling in atherosclerosis development. Bone marrow (SIRP{Delta}CYT>LDLR-/-) chimaeric mice developed reduced atherosclerosis accompanied by increased natural antibody production. Collectively, our data identify SIRP as a unique B1 cell inhibitory receptor acting to control B1 cell migration, and imply SIRP as a potential therapeutic target in atherosclerosis.

immunology↗