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

Objective: To investigate the effects of interferon beta treatment on T-cel l interferon gamma binding (which is a possible marker for T-cell-dependent immune function) in patients with multiple sclerosis (MS). Design: Assay interferon gamma binding on T lymphocytes from patients with stable relapsing-remitting MS before, 3 months after, and 6 months after in itiating interferon beta-lb treatment. Setting: The study was performed on ambulatory patients in a tertiary care center, where patients were diagnosed as having definite MS. Patients: Eighteen patients with clinically definite, stable, relapsing-rem itting MS (13 women and 5 men; mean age [+/- SD] 32.6 +/- 7.1 years) were s elected 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-lb subcutaneously every other day. Eighteen age- and se x-matched healthy subjects with no family history of neuropsychiatric disor ders formed the control group. Results: T lymphocytes from untreated patients with MS had significantly sm aller amounts of interferon gamma receptors than those from control subject s (638 +/- 7 [ SE] vs 707 +/- 11 [SE] receptors per cell). After 3 months o f interferon beta-lb treatment, they showed a significant increase in inter feron 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 . Conclusion: Given that reduced interferon gamma binding might be related to lymphocyte activation, our data seem to demonstrate that the major effect of interferon beta-1b treatment is a decrease in T-cell activation.