Search Results (103)

Background: Idiopathic pulmonary fibrosis (IPF) is closely associated with fibroblast proliferation, macrophage polarization, and the accumulation of extracellular matrix (ECM). Targeting CSF-1R can rebalance macrophages, reduce ECM deposition, and block pro-fibrotic signaling. Methods: A Fab fragment targeting CSF-1R was screened via phage display. After sequence optimization, it was constructed into an IgG1 antibody (BC006). In vitro activity, domain binding, and signaling blockade were investigated, and in vitro safety indicators were evaluated. Efficacy was assessed using an induced IPF organoid-on-a-chip and bleomycin-induced mouse model. In vivo safety evaluation was conducted in cynomolgus monkeys. Results: BC006 showed an EC₅₀ value of 226 ± 57 nM and a KD of 30 ± 2 nM. It specifically bound to the Ig4-5 domain of CSF-1R by inhibiting receptor dimerization without blocking ligand binding. It could dose-dependently inhibit the differentiation of monocytes into M2 macrophages and exert anti-IPF effects. In the induced IPF organoid-on-a-chip model, BC006 maintained lung barrier function and decreased α-SMA and Collagen I. It also improved lung function and attenuated the degree of fibrosis in the mouse model. Moreover, BC006 had no ADCC, CDC, cytokine release, or hemagglutination, and demonstrated favorable safety profiles in cynomolgus monkeys. Conclusions: BC006 is a novel anti-fibrosis antibody specifically targeting the CSF-1R Ig4-5 domain and offers a new therapeutic strategy for IPF. Full article

Background/Aim: Pancreatic cancer remains one of the most lethal malignancies, with limited therapeutic options and an extremely poor prognosis. MicroRNAs (miRNAs), which regulate gene expression at the post-transcriptional level, have emerged as promising candidates for next-generation cancer therapeutics. The purpose of this study is to clarify the feasibility of miR-4711 as a potential therapeutic option against pancreatic cancer. Materials and Methods: The effects of miR-4711-5p were examined in pancreatic cancer cell lines with respect to cell proliferation, apoptosis, cancer stemness, cell cycle progression, and invasive capacity. RNA sequencing and in silico analyses were performed to identify potential target genes of miR-4711-5p. For in vivo safety evaluation, miR-4711-5p was formulated with super carbonate apatite, a delivery vehicle that is already amenable to large-scale production, and administered to cynomolgus monkeys. A nucleic acid dose equivalent to 10 times the effective dose observed in prior mouse efficacy studies was used. General clinical conditions, body weight, food consumption, ophthalmologic findings, electrocardiography, blood pressure, hematological and biochemical parameters, and histopathological changes were systematically assessed. Results: miR-4711-5p significantly suppressed cancer stemness, cell proliferation, and invasion, while inducing apoptosis and delaying cell cycle progression in pancreatic cancer cells. RNA sequencing and bioinformatic analyses identified MET, CTSA, and ANO1 as potential target genes of miR-4711-5p. In the cynomolgus monkey study, administration of miR-4711-5p formulated with super carbonate apatite resulted in no apparent differences compared with the control group in body weight, clinical observations, laboratory parameters, or histopathological findings, indicating the absence of treatment-related adverse effects even at a supra-therapeutic dose. Conclusions: These findings demonstrate that miR-4711-5p exerts potent antitumor effects against pancreatic cancer cells while exhibiting a favorable safety profile in a non-human primate model. Collectively, this study provides strong preclinical evidence supporting miR-4711-5p as a novel and safe therapeutic strategy for pancreatic cancer and represents an important step toward clinical application. Full article

Complement and pathogenic antibodies act independently and together to mediate the pathology of many autoimmune diseases. To address these drivers of disease, we generated a monoclonal antibody (mAb), CSL305, that binds and inhibits both complement and the neonatal Fc (fragment crystallizable) receptor FcRn. The fragment antigen binding (Fab) portion of CSL305 was engineered to bind both human C2 (huC2) zymogen and the active fragment huC2b to inhibit the classical and lectin complement pathways in vitro, and C3b deposition on primary lung endothelial cells using a 3-dimensional microvascular model system. Engineering of a triple amino acid mutation (“YPY” motif) into the Fc region of CSL305 increased its affinity to FcRn at both acidic and neutral pH, allowing it to also act as a potent FcRn antagonist. Intracellular trafficking experiments demonstrated that CSL305, but not the wild-type (WT) mAb lacking the YPY motif, was able to block immunoglobulin G (IgG) recycling in vitro. The generation of a high resolution 2.6Å crystal structure of CSL305 Fab region bound to huC2b showed that the epitope lies directly over the huC2b catalytic triad, providing evidence of its complement mechanism of action as a neutralising mAb. Early pharmacokinetic (PK)/pharmacodynamic (PD) studies using CSL305 in cynomolgus monkeys demonstrated both complement inhibition and FcRn antagonism in vivo, with reductions in complement classical pathway activity and endogenous IgG observed following single intravenous (IV) administration. CSL305 thus represents a dual-functional mAb as a potential therapeutic candidate. Full article

A case of peritonitis in a female cynomolgus monkey (Macaca fascicularis) caused by suspected bacterial infection was found. In order to identify the pathogenic bacteria, pathological tissues from the peritoneum of the animal were collected, and a bacterial strain designated MF080196 was isolated. Morphological observations were conducted, followed by biochemical testing and sequencing of its 16S rRNA gene. Additionally, pathogenicity test and drug sensitivity analyses were performed. The findings indicated that colonies grown on blood agar medium appeared white, circular, and raised; the bacteria were identified as Gram-negative; biochemical tests aligned with the characteristics of Acinetobacter lwoffii (A. lwoffii). PCR amplification was performed using a 16S rRNA sequence measuring 1443 bp; there was a remarkable similarity of 99.8% with previously reported sequences of A. lwoffii from various sources. The isolated strain MF080196 is capable of mortality in mice; furthermore, drug susceptibility testing revealed that the isolated strain exhibited high sensitivity to 23 antibiotics, including ceftriaxone, gentamicin, and levofloxacin. The pathogen isolated from the peritoneal tissue of the dead cynomolgus monkey was identified as A. lwoffii, which demonstrated sensitivity to most antibiotics tested in this study. This research provides significant insights for preventing and treating bacterial diseases in non-human primates. Full article

Background: Pneumococcal diseases remain a global threat due to the serotype-specific limitations of polysaccharide vaccines. This study evaluated a recombinant protein-based pneumococcal vaccine (PBPV) combining three PspA variants (PRX1/Family1Clade2, P3296/Family2/Clade3, P5668/Family2/Clade4) and detoxified pneumolysin (PlyLD). PspA targets conserved surface epitopes to block immune evasion and achieve broad coverage, while PlyLD neutralizes pore-forming toxins and enhances adaptive immunity. Methods: We evaluated the safety and immunogenicity of the PBPV in animal models. Acute toxicity studies were conducted by administering a single intramuscular injection to ICR mice, whereas chronic toxicity and immunogenicity studies were performed in cynomolgus monkeys via repeated intramuscular injections, with an equal number of male and female animals in both groups. Immune responses were assessed using ELISA, multiplexed opsonophagocytic killing assays (MOPAs), and neutralizing antibody assays. Results: Acute toxicity studies in ICR mice showed no signs of abnormal toxicity or irritation at one-dose levels. In the chronic toxicity study, cynomolgus monkeys received repeated intramuscular injections once every 3 weeks for a total of four administrations, at doses of one dose/monkey and five doses/monkey, followed by a 4-week recovery period. No significant systemic toxic reactions were observed, and the safe dose was determined to be five doses/monkey. In the immunogenicity study of monkey serum, both low-dose and high-dose groups demonstrated significant increases in antigen-specific IgG titers against each component; opsonophagocytic killing activity against pneumococcal strains from Clades 2, 3, and 4 from PspA Families 1 and 2; and neutralization antibody titers against pneumolysin post-vaccination. Conclusions: The recombinant protein-based pneumococcal vaccine exhibited a favorable safety profile and potent immunogenicity in animal models, indicating promise for broad protection against pneumococcal disease. These findings support the further development of PBPVs as a viable alternative to conventional polysaccharide-based vaccines. Full article

Background: Immune aging is a complex process involving various cellular changes, such as a myeloid bias, decreased functional activity of immune cells, accumulation of senescent cells, and alterations in serum levels of bactericidal humoral factors. As believed, these changes contribute to increased susceptibility of older adults to infectious diseases. Myeloid cells are considered the first line of defense against bacterial invasion. However, it remains unclear whether the protective functions of myeloid cells diminish in active older adults and whether potential age-related changes are evolutionarily conserved across primates. Methods: In this study, myeloid cell populations from peripheral blood and bone marrow of cynomolgus macaques and human peripheral blood were analyzed across a broad age range for phenotypic and functional characteristics, e.g., E. coli phagocytosis, secretion of proinflammatory factors, genetic instability, and signs of cellular aging. Results: Despite minor interspecies phenotypic differences in granulocyte populations, both the quantity and functions of myeloid cells were remarkably stable during aging in both species. Myeloid cells maintained genetic stability, and high SA-β-Gal activity was observed, likely reflecting metabolic traits rather than age-related changes. Importantly, a predominant and age-independent role of humoral factors, rather than cellular mechanisms, was identified in the initial control of bacterial infection. Conclusions: These findings suggest that innate immune functions remain stable for a long time during aging in both species. Full article

This study compared the gonadotropin gene sequences (LH and FSH subunits) of Cynomolgus and Rhesus monkeys and produced recombinant single-chain LHβ/α and FSHβ/α proteins. The α- and FSHβ-subunit sequences were identical between species, while LHβ showed only minor synonymous differences. The recombinant hormones were successfully expressed and shown to be mainly N-glycosylated. Recombinant monkey FSHβ/α activated cAMP signaling in human FSH receptor-expressing cells, confirming its biological activity. β-arrestin 1 was found to have dual roles: its absence increased cAMP signaling (negative regulation), but it was required for ERK1/2 activation. ERK activation depended mainly on the cAMP/PKA pathway. Human and rat FSH receptors displayed different ERK activation timing, indicating species-specific signaling behavior. Overall, the study establishes a reliable system for producing functional recombinant monkey gonadotropins and clarifies how β-arrestin 1 differentially regulates FSH receptor signaling. Full article

Background/Objectives: Leucine-rich repeat kinase 2 (LRRK2) is an enzyme implicated in Parkinson’s disease (PD) and a potential therapeutic target. LRRK2 PET radioligands could therefore function as imaging biomarkers for PD and as tools to measure enzyme occupancy of novel therapeutic candidates. This study aimed at developing novel radioligands for imaging using positron emission tomography (PET). Specific objectives were to synthesize fluorine-18-labeled pyrrolopyridine 1 ([¹⁸F]1), pyrrolo-pyrimidine 2 ([¹⁸F]2), as well as carbon-11-labeled pyrrolo-pyrimidine 3 ([¹¹C]3), and examine their binding specificity, using in vitro autoradiography (ARG) and in vivo positron emission tomography (PET) imaging in non-human primates (NHPs). Methods: Radiolabeling was achieved either by classical one-step fluorine-18 nucleophilic substitution reaction or by methylation using carbon-11 methane. [¹⁸F]1 and [¹⁸F]2 were tested in NHP and human whole-hemisphere ARG experiments. PET imaging was performed in cynomolgus monkeys. Radiometabolites were measured in monkey plasma using gradient HPLC. Results: The results demonstrated successful radiolabeling of all three ligands. In ARG studies, both [¹⁸F]1 and [¹⁸F]2 displayed binding in brain slices from NHP and human samples. The binding of [¹⁸F]1 was blocked by cold Compound 1 and structurally distinct Compound 3, but not by the structurally distinct LRRK2 inhibitor PFE-360. On the other hand, the binding of [¹⁸F]2 was blocked by PFE-360 in certain regions of the brain, indicating some level of specific binding to LRRK2. All three ligands showed relevant brain uptake (>3%ID), with highest uptake being observed for [¹⁸F]1, particularly in the thalamus. In contrast, brain uptake of [¹⁸F]2 and [¹¹C]3 was evenly distributed across all brain regions. No blocking effect of [¹⁸F]1 was observed after pretreatment with the structurally distinct LRRK2 inhibitors PFE-360 (0.5 mg/kg, iv) and GEN-7915 (40 mg/kg). Conclusions: PET imaging indicated a low in vivo specific binding of the radioligands in the cynomolgus monkey brain, suggesting that the radioligands are not suitable for LRRK2 imaging in vivo with PET. This study emphasizes the challenges in the development of PET radioligands for imaging LRRK2 and the need for additional work to achieve this goal. Full article

Background/Objectives: Cadherin-6 (CDH6), also known as K-cadherin, is a type II classic cadherin molecule that plays an important role in the embryonic development of the kidney but has very limited expression in adult tissues. It is overexpressed in several human malignancies, primarily in ovarian cancer, renal cell carcinoma, as well as, less frequently, cholangiocarcinoma, uterine serous carcinoma, glioma, lung, pancreatic and thyroid cancers. The characteristic of limited expression in normal tissues, high expression in tumor tissues, and rapid internalization upon antibody binding makes CDH6 a well-suited antibody-drug conjugate (ADC) target. Methods: We developed a novel CDH6-targeting ADC, CUSP06, consisting of a proprietary humanized antibody selective for CDH6, a protease cleavable linker, and an exatecan payload, with a drug-to-antibody ratio (DAR) of 8. We further characterized the pharmacological activities of CUSP06 in multiple in vitro and in vivo models. Results: CUSP06 was selectively bound to cell surface CDH6 and was efficiently internalized into CDH6-positive ovarian cancer cells, and led to the induction of DNA damage and apoptosis of CDH6-positive cancer cells. CUSP06 exhibited strong antiproliferative activity against several CDH6-positive cancer cell lines and demonstrated strong bystander cell killing effect in the cell mixing experiments in vitro. CUSP06 exhibits excellent in vivo antitumor efficacy in CDH6-high or -low cell line-derived xenograft (CDX) or patient-derived xenograft (PDX) models from human ovarian, renal and uterine cancers, as well as cholangiocarcinoma. CUSP06 demonstrated a favorable safety profile in GLP-compliant toxicology studies in Sprague Dawley rats and cynomolgus monkeys. Conclusions: The preclinical data highlighted the therapeutic potential of CUSP06 in multiple CDH6-positive human cancers. Full article

In this study, we isolated and identified bacteria from the feces of a diarrheal cynomolgus monkey. The results showed that the isolated strain was P. aeruginosa, named PA/CM-101101. Morphological observations indicated that when cultured on Luria–Bertani (LB) nutrient agar at 37 °C for 24 h, the strain formed smooth, slightly elevated colonies with neat and wavy edges. On acetamide agar at the same temperature and duration, the colonies appeared flat with irregular edges and a faint pink periphery, while the medium changed to rose-red; in LB broth at 37 °C for 24 h, the medium became turbid and yellowish-green. Gram staining revealed that it was negative and rod-shaped, without sporulation characteristics. The 16S rRNA gene sequence analysis showed that the sequence identity of the strain shared more than 98.4% similarity with 11 strains of P. aeruginosa from various sources in GenBank. The animal toxicity test showed that it had a strong pathogenic effect on mice. The results of drug sensitivity tests showed that strain PA/CM-101101 was sensitive to amikacin, azithromycin, cefoperazone, ceftazidime, ceftriaxone, ciprofloxacin, gentamicin, imipenem, levofloxacin, meropenem, norfloxacin, ofloxacin, and polymyxin B; however, it displayed resistance to ampicillin, cefadroxil, cefazolin, erythromycin, and vancomycin. The research findings provide valuable insights for diagnosis and treatment strategies for cynomolgus monkeys. It also provides a reference for molecular epidemiological studies. To our knowledge, this is the first time P. aeruginosa isolated from the diarrhea feces of cynomolgus monkey has been reported. Full article

Background: In vitro blood circulation loop systems are utilized to assess the hemocompatibility and performance of medical devices that come into contact with blood, in accordance with the international standards ASTM F1830 and ASTM F1841. However, a method for evaluating the specific type of anticoagulant and the blood characteristics of each animal species is necessary to ensure consistent and reliable results. Methods: Blood was collected from healthy rabbits, pigs, rhesus monkeys, and cynomolgus monkeys to evaluate whole blood preserved in anticoagulants (ACD-A, CPDA-1, and heparin). For each sample, red blood cells were monitored over time, and their morphological characteristics were documented. Results: The morphological grade of erythrocytes gradually decreased over time. Significant differences were observed based on the type of anticoagulant used in the experiment, and variations were noted among different animal species. Conclusions: The hemocompatibility of in vitro blood circulation loop systems may vary depending on the animal species. Observing erythrocyte morphology can serve as a control measure to ensure reproducible results. Full article

Recent advances in tissue clearing chemistry have revolutionized three-dimensional imaging by enabling whole-organ antibody labeling, even in thick human tissue samples. However, these techniques face limitations, including reduced clearance efficiency in thick tissue blocks, prolonged processing times, and other challenges specific to formalin-fixed human brain tissue, such as autofluorescence due to the presence of lipofuscin, neuromelanin pigments, and residual blood. To address these challenges, we have developed an improved SHANEL procedure, iSHANEL, which is compatible with brain tissue from multiple species, including nonrodents. iSHANEL significantly enhances the tissue transparency. It effectively removes lipids, particularly sphingolipids, from brain tissue across different species. For brain vasculature imaging, it offers the better visualization of vascular structures at high magnification, reducing light scattering and background noise. Moreover, iSHANEL can be effectively applied to large tissue from pigs and cynomolgus monkeys, and it preserves protein immunogenicity well, as evidenced by immunostaining with the microglia-specific marker IBA-1. We also investigated methods to reduce blood vessel autofluorescence. Overall, iSHANEL provides an improved procedure for the high-resolution 3D imaging of brain tissue across multiple species. Full article

Nicotinic acetylcholine receptor (α7-nAChR) plays a crucial role in cognitive functions like memory and attention. Positron emission tomography (PET) imaging of α7-nAChR is gaining attraction for understanding and monitoring central nervous system disorders, such as Alzheimer’s disease, Parkinson’s disease, and schizophrenia. We developed [¹¹C]KIn83, a novel α7-nAChR radioligand, and evaluated its biological properties. This study focused on two objectives: (1) to validate its Good Manufacturing Practice (GMP)-compliant production, and (2) to assess the dosimetry of [¹¹C]KIn83 using non-human primate (NHP) whole-body PET data. Radiolabeling and drug product delivery of [¹¹C]KIn83 were conducted using an automated synthesis module within a controlled GMP environment. The quality control tests performed adhered to the European Pharmacopoeia guidelines. The production of [¹¹C]KIn83 was validated according to GMP standards, encompassing automated synthesis and quality control measures. For the dosimetry assessment, two female cynomolgus monkeys underwent whole-body PET scans. The radioactivity values injected for [¹¹C]KIn83 were 150 MBq and 155 MBq, respectively, with an estimated radiation dose of 0.0047 mSv/MBq. Our findings pave the way for future clinical studies that investigate the potential of [¹¹C]KIn83 to measure α7-nAChR, aiding our understanding and possibly supporting diagnoses of different cognitive disorders. Full article

Background/Objectives: Finotonlimab (SCTI10A) is a humanized anti-PD-1 antibody tested in Phase III trials for several solid tumor types. Methods: This study characterized the in vitro and in vivo efficacy, Fc-mediated effector function, and non-clinical PK/PD properties of finotonlimab. Results: The results demonstrated that finotonlimab is effective in stimulating human T cell function in vitro and exhibits marked antitumor efficacy in vivo using both PD-1-humanized and PBMC-reconstructed mouse models. Additionally, finotonlimab exhibited minimal impact on the activation of effector cells via Fc receptor-dependent pathways, potentially facilitating PD-1⁺ T cell killing. In cynomolgus monkeys, finotonlimab exhibited a nonlinear pharmacokinetic (PK) profile in a dose-dependent manner, and a receptor occupancy rate of approximately 90% was observed at 168 h following a single administration of 1 mg/kg. Finotonlimab’s PK profile (especially C_max) was better than that of marketed antibodies. Following a 13-week successive administration of finotonlimab, a pharmacodynamic analysis revealed that a sustained mean receptor occupancy of PD-1 molecules on circulating T cells remained at or above 93% for up to 8 weeks, even at a dose of 3 mg/kg, and that there were higher antibody accumulations in different dose groups. Conclusions: Taken together, the preclinical findings are promising and provide the groundwork for evaluating the efficacy and pharmacodynamic characteristics of finotonlimab in clinical trials. Full article

Background: The therapeutic blockade of the PD1/PD-L1 axis with monoclonal antibodies has led to a breakthrough in cancer treatment, as it plays a key role in the immune evasion of tumors. Nevertheless, treating patients with cancer with vaccines that stimulate a targeted immune response is another attractive approach for which few side effects have been observed in combination immunotherapy clinical trials. In this sense, our group has recently developed a therapeutic cancer vaccine candidate called PKPD-L1^Vac which contains as an antigen the extracellular domain of human PD-L1 fused to a 47 amino-terminal, part of the LpdA gene of N. meningitides, which is produced in E. coli. The investigation of potential toxicities associated with PD-L1 blockade by a new therapy in preclinical studies is critical to optimizing the efficacy and safety of that new therapy. Methods: Here, we describe immunogenicity and preliminary safety studies in mice, rats, rabbits, and non-human primates that make use of a 200 μg dose of PKPD-L1 in combination with VSSPs or alum phosphate to contribute to the assessment of potential adverse events that are relevant to the future clinical development program of this novel candidate. Results: The administration of PKPD-L1^Vac to the four species at the doses studied was immunogenic and did not result in behavioral, clinical, hematological, or serum biochemical changes. Conclusions: Therefore, PKPD-L1^Vac could be considered suitable for further complex toxicological studies and the way for its clinical evaluation in humans has been opened. Full article