The tripeptide Arginyl-Glycyl-Aspartic acid (RGD) is a common cell recognition site of many adhesive proteins contained in extracellular matrices and in the blood .

• RGD三肽（精氨酰-甘氨酰-天冬氨酸）序列是细胞外基质及血液中的许多粘附蛋白共有的细胞识别位点。