Summary:Monocyte chemoattractant protein-1 (MCP-1) is expressed in the ischemic cortex after focal brain ischemia and appears to exacerbate ischemic damage. The authors examined the effect of gene transfer of dominant negative MCP-1, called 7ND, 90 minutes after induction of focal brain ischemia in hypertensive rats. Adenoviral vectors encoding mutant MCP-1 (Ad7ND; n ס 11), or Escherichia coli -galactosidase (AdlacZ; n ס 17) as control were injected into the lateral ventricle of male spontaneously hypertensive rats. Both AdlacZ (n ס 12) and Ad7ND (n ס 6) administration provided transgene expression as early as 6 hours after injection and the expression further increased on day 1, followed by a sustained detection on day 5. Five days after ischemia, infarct volume (75 ± 13 mm 3 , n ס 5, mean ± SD) significantly reduced to 72% of control (104 ± 22 mm 3 , n ס 5, P < 0.05) by 7ND gene transfer. Numbers of leukocytes in the vessels (48.3 ± 32.9/cm 2 ) and macrophage/monocyte infiltration (475.2 ± 125.5 /mm 2 ) of the infarct area in the Ad7ND group were significantly less than those measured in the AdlacZ group (143.8 ± 72.1/cm 2 and 671.8 ± 125.5/mm 2 , P < 0.05, respectively). In summary, the postischemic gene transfer of dominant negative MCP-1 attenuated the infarct volume and infiltration of inflammatory cells, suggesting potential usefulness of the anti-MCP-1 gene therapy.