Angiogenesis, the formation of new blood vessels from pre-existing ones, plays a pivotal role in various pathological conditions, particularly ocular diseases such as choroidal neovascularization (CNV). CNV is characterized by the abnormal proliferation and migration of endothelial cells (ECs), leading to retinal damage and potential blindness. Current therapeutic strategies primarily target vascular endothelial growth factor (VEGF) using monoclonal antibodies like bevacizumab, ranibizumab, and aflibercept. While these agents have shown clinical efficacy, challenges remain, including limited response in approximately 15% of patients, drug resistance, and the need for frequent intravitreal injections due to short half-life.

To address these limitations, we developed an innovative biomimetic superstructure drug—an antibody-like peptidic network (ALPN)—designed to target neuropilin-1 (NRP-1), a key receptor involved in angiogenesis signaling pathways. Unlike conventional small-molecule inhibitors or monoclonal antibodies, ALPN leverages self-assembling peptide technology to form a fibrous network on EC surfaces, enabling multivalent binding and long-term retention.MYH9 Antibody Biological Activity The ALPN monomer consists of three functional motifs: a bis-pyrene (BP) fluorophore for visualization, a fibrillogenesis sequence (FFVLK) that promotes self-assembly into nanofibers, and a targeting sequence (RPL) derived from phage display, which specifically binds NRP-1 overexpressed on activated ECs.PGP 9.5 Antibody Protocol

Upon injection into the vitreous body of CNV rat models, ALPN monomers rapidly self-assemble into nanoparticles (ALPN-NPs).PMID:34923308 These nanoparticles bind to NRP-1 on the EC surface, triggering a conformational change that initiates in situ fibrillogenesis, transforming ALPN-NPs into a dense, stable nanofibrous network. This network effectively traps and blocks NRP-1, preventing its interaction with multiple pro-angiogenic ligands such as VEGF, platelet-derived growth factor (PDGF), and hepatocyte growth factor (HGF). As a result, downstream signaling cascades responsible for EC migration, proliferation, and vessel formation are significantly suppressed.

In vitro studies demonstrated that ALPN-NPs selectively bind to NRP-1-overexpressing human umbilical vein endothelial cells (HUVECs), forming a visible fibrous layer on their surface without cytotoxicity. In contrast, control C-ALPN-NPs lacking the fibrillogenesis motif were internalized and failed to form surface networks. Functional assays confirmed that ALPN dramatically inhibited HUVEC migration and tube formation, while having minimal effects on non-target cells like 293T cells. In the chorioallantoic membrane (CAM) model, ALPN treatment led to a significant reduction in new vessel formation, confirming potent anti-angiogenic activity.

In vivo evaluations revealed exceptional retention of ALPN in the CNV region, with strong green fluorescence persisting up to four days post-injection—far exceeding the transient presence of control nanoparticles. Immunofluorescence staining showed marked depletion of NRP-1 signals in ALPN-treated eyes, indicating effective blockade. Histological analysis confirmed reduced CNV area and improved retinal structure, comparable to bevacizumab treatment. Notably, ALPN achieved this effect at a dose of just 0.263 μg/kg—89.3 times lower than the 23.5 μg/kg required for bevacizumab—highlighting its superior potency and efficiency.

These findings underscore the transformative potential of ALPN as a next-generation anti-angiogenic therapy. By mimicking extracellular matrix-cell interactions through a self-assembled fibrous network, ALPN provides sustained, multivalent inhibition of NRP-1, overcoming key drawbacks of traditional antibodies. Its modular design allows for future adaptation to other targets and diseases involving pathological angiogenesis, such as retinal neurovascular disorders, corneal neovascularization, and tumor angiogenesis. Thus, ALPN represents a promising paradigm shift in therapeutics, offering enhanced efficacy, reduced dosing frequency, and broader applicability in precision medicine.MedChemExpress (MCE) offers a wide range of high-quality research chemicals and biochemicals (novel life-science reagents, reference compounds and natural compounds) for scientific use. We have professionally experienced and friendly staff to meet your needs. We are a competent and trustworthy partner for your research and scientific projects.Related websites: https://www.medchemexpress.com