Apln-CreERT:mT/mG reporter mice as a tool for sprouting angiogenesis study

Area of Science:

• Vascular Biology
• Developmental Biology
• Oncology

Background:

• Angiogenesis, the formation of new blood vessels, is crucial for development and disease.
• Sprouting angiogenesis is a key early phase in this process.
• Understanding its mechanisms is vital for treating diseases like cancer and retinopathy.

Purpose of the Study:

• To develop and validate a novel mouse model for studying sprouting angiogenesis.
• To differentiate new blood vessel formation from existing vasculature in vivo.
• To investigate the role of Apelin in sprouting angiogenesis.

Main Methods:

• Generation of Apln-CreERT:mT/mG reporter mice by crossing mT/mG mice with Apln-CreERT mice.
• Utilized neonatal retinal angiogenesis and in vivo tumor models.
• Employed Fluorescence-Activated Cell Sorting (FACS) to analyze Apelin and Cdh5 expression in endothelial cells.
• Observed angiogenic patterns under varying conditions (tamoxifen induction, hypoxia).

Main Results:

• Apln-CreERT:mT/mG mice specifically labeled sprouting angiogenesis with eGFP.
• Apelin expression was higher in sprouting endothelial cells compared to mature vessels.
• Sprouting angiogenesis decreased with tamoxifen administration but increased under hypoxia.
• Tumor-associated sprouting angiogenesis was successfully visualized in dorsal skinfold models.

Conclusions:

• The Apln-CreERT:mT/mG mouse line is an effective tool for distinguishing sprouting angiogenesis.
• This model facilitates in vivo investigations of retinal and tumor angiogenesis.
• Provides a valuable resource for studying angiogenesis-related diseases.