T-cell interferon gamma receptor binding in interferon beta-1b-treated patients with multiple sclerosis

To investigate the effects of interferon beta treatment on T-cell interferon gamma binding (which is a possible marker for T-cell-dependent immune function) in patients with multiple sclerosis (MS).

Assay interferon gamma binding on T lymphocytes from patients with stable relapsing-remitting MS before, 3 months after, and 6 months after initiating interferon beta-1b treatment.

The study was performed on ambulatory patients in a tertiary care center, where patients were diagnosed as having definite MS.

Eighteen patients with clinically definite, stable, relapsing-remitting MS (13 women and 5 men; mean age [+/-SD] 32.6+/-7.1 years) were selected consecutively. Clinical status was defined according to the Kurtzke Expanded Disability Status Scale. All patients were treated with 8 x 10(6) IU interferon beta-1b subcutaneously every other day. Eighteen age- and sex-matched healthy subjects with no family history of neuropsychiatric disorders formed the control group.

T lymphocytes from untreated patients with MS had significantly smaller amounts of interferon gamma receptors than those from control subjects (638+/-7 [SE] vs 707+/-11 [SE] receptors per cell). After 3 months of interferon beta-1b treatment, they showed a significant increase in interferon gamma binding (681+/-9 [SE] receptors per cell). After 6 months, T-cell interferon gamma maximal receptor values were even higher (700+/-7 [SE] receptors per cell), only slightly lower than those of control subjects.

Given that reduced interferon gamma binding might be related to lymphocyte activation, our data seem to demonstrate that the major effect of interferon beta-lb treatment is a decrease in T-cell activation.