Multiple sclerosis: effects of activated T-lymphocyte-derived products on organ cultures of nervous tissue

Supernatants from multiple sclerosis (MS) T-lymphocytes cause damage to both myelin and glial cells in cerebellar cultures assessed visually and by radiolabel release. Control T-lymphocytes, even after phytohaemagglutinin (PHA) stimulation, yielded supernatants which induced only slight damage, and at later times patients with other neurological diseases (OND) gave variable results. These differences suggest that MS T-lymphocytes are pre-activated in vivo to produce demyelinating factors while control T-lymphocytes are not pre-activated to the same extent. The visual evidence of activation of cerebellar macrophage-like cells was a common finding after MS T-lymphocyte supernatant treatment but there was no correlation with the severity of demyelination. There was a positive correlation between the percentage IL-2 receptor-bearing lymphocytes and the degree of supernatant-induced in vitro demyelination.