Multi‑scale experimental models for the study of angiogenesis (Review)

Angiogenesis is defined as the formation of new blood vessels originating from pre‑existing vasculature and serves a critical role in physiological developmental processes. In addition, angiogenesis serves important roles in various pathological conditions, such as diabetic retinopathy, psoriasis, and tumor progression and metastasis. A primary challenge in this field remains the selection of appropriate assays to elucidate the underlying molecular mechanisms, evaluate the efficacy of potential therapeutic agents and identify viable targets within the angiogenic pathway. Given that heterogeneity exists not only amongst endothelial cells themselves but also within the specific microenvironment under investigation, it is crucial to select appropriate assay conditions and cell types that can most accurately reflect the angiogenic pathology being studied. Therefore, the present review documents the advantages and limitations of the principal angiogenesis assays currently in use, including those for the proliferation, migration, two‑dimensional tube formation and three‑dimensional tubulogenesis of endothelial cells in vitro, vessel outgrowth from retinal explants, and aortic rings ex vivo and in vivo assays (such as hindlimb ischemia models, corneal neovascularization assays, retinal vascularization assays, zebrafish models, chick chorioallantoic membrane assays and tumor angiogenesis models). The aim of the present review is to perform a comprehensive analysis of angiogenesis models to establish a foundational framework for subsequent experimental studies on angiogenesis‑related pathologies.