COMPARISON OF 3 DIFFERENT TECHNIQUES TO ASSESS ANGIOGENESIS USING THE CHICK EMBRYO CHORIOALLANTOIC MEMBRANE MODEL

Renuka Munshi*, Rima Mittra and Tanvi Patil

ABSTRACT

Angiogenesis is the growth of blood vessels from the existing vasculature. A variety of methods have been used to assess angiogenesis. One widely accepted is the Chick Chorioallantoic membrane (CAM) model. Quantification of blood vessels in the CAM model using Stereomicroscope and the Image Analysis software, is one of the easy, reproducible and validated technique, but it is not economical. Hence, there is a need for an alternative technique which has the consistency of the Image analysis method but is cost effective. Thus, the present study was aimed to compare 3 different techniques of CAM model, 2 known and one novel (Drabkin‟s method), in determining the angiogenic potential of drugs. 6-day old embryonated White Leghorn eggs were used for the CAM model. The angiogenic potential of 3 standard drugs viz., VEGF, Erythropoietin and Heparin was assessed using 3 techniques, viz., Drabkin‟s method, Overall quantification of blood vessels (using Stereomicroscope) and Localized quantification of blood vessels (using discs).6-day old embryonated eggs were inoculated with the known drugs respectively, and incubated. Untreated eggs served as the normal control. On day 12, CAM was excised from the eggs and the effect of the drugs on angiogenesis was evaluated by the 3 techniques and compared. All techniques evaluated in the study demonstrated comparable results with significant Pearson‟s correlation (r = 0.9877, p<0.0001). Significant correlation between the Drabkin‟s method results and both the image analysis methods demonstrated that Drabkin‟s method is a relatively cheaper, reproducible and a reliable technique to screen drugs for their angiogenic potential.

Keywords: Angiogenesis; CAM; Drabkin?s method; Image Analysis methods.