In another example, to assess the effect of simultaneous expression of two proteins that synergistically promote angiogenesis, stromal cell-derived factor 1 (SDF-1) and VEGF proteins, an AAV expressing VEGF165 and SDF-1 connected via an IRES was used in a rat model of cerebral infarction [158]. Here, CXCL12 is linked to cerebral infarction.