VCAM-1 expression on reactive and tumour astrocytes.

In our studies we used a monoclonal antibody recognizing the vascular adhesion molecule (VCAM-1). Tissue samples were collected at autopsy from human brain infarcts and from brain tumours, removed during surgical procedure (Neurological and Neurosurgical Clinic, Cracow). A novel, unexpected finding were VCAM-1-positive fibrous astrocytes in the stroke tissue, and astrocyte-like cells in the tumours. No staining was obtained either in the contralateral hemisphere or outside of ischemic areas. Likewise, no positive staining of cells was seen outside the tumour tissue. The above findings, taken together, strongly support the concept that astrocytes take part in the immune defense during various pathological processes in the human brain.