Evaluate the collective function of references cited together in a given text segment.
Classify their combined role into one of the following categories: 'method', 'background', or 'result'.

Text:There is evidence that Ang-2 acts as a chemoattractant for regulating monocyte/macrophage infiltration [5, 23], suggesting that treatment with r-Ang-2 may increase macrophage recruitment to remodelling collateral arterioles.
Category: