GLIAL TRANSFORMING GROWTH-FACTOR (TGF)-BETA ISOTYPES IN MULTIPLE-SCLEROSIS - DIFFERENTIAL GLIAL EXPRESSION OF TGF-BETA-1, TGF-BETA-2 AND TGF-BETA-3 ISOTYPES IN MULTIPLE-SCLEROSIS

We studied glial transforming growth factor (TGF)-beta isotype express ion in 14 cases of multiple sclerosis. Acute active lesions exhibited selective TGF-beta 2 immunoreactivity of lesion encircling ramified mi croglia. In contrast, astrocytes within chronic active white matter le sions expressed all three isotypes. Chronic active lesions which exten ded into cortex exhibited selective cortical astrocyte TGF-beta 2 expr ession. This isotype was also selectively expressed by astrocytes in a pparently normal white matter. A similar pattern of glial TGF-beta exp ression was seen in the pathological control: progressive multifocal l eukoencephalopathy The results suggest that TGF-beta cytokines are loc ally expressed in demyelination and that the beta 2 isotype may be uni quely regulated.