Cytokine and IL-12 receptor mRNA discriminate between different clinical subtypes in multiple sclerosis

Little is known about the involvement of cytokines in the pathogenesis of p rimary progressive (PP) multiple sclerosis (MS). We evaluated in this cross -sectional study whether IL-18, IL-12p35, IL-12p40, TNF-alpha, IFN-gamma, I L-10, IL-4, TGF-beta, IL-12R beta1, and IL-12R beta2 mRNA expression in uns timulated white blood cells showed significant differences between relapsin g-remitting (RR), secondary progressive (SP) and PP MS patients, and health y controls. All clinical subtypes showed unique mRNA expression patterns as compared to the controls. Both RR and SP patients displayed increased leve ls of IL-12p40, IL-18, and TGF-beta mRNA compared to controls, whereas PP p atients showed only increased IL-18 mRNA levels. Both in PP and SP patients , IFN-gamma and IL-10 mRNA were decreased compared to RR patients and contr ols. PP patients were unique in that they showed decreased IL-12R beta1 mRN A. In conclusion, our data show that the assessment of cytokine (receptor) mRNA profiles is useful to discriminate between the different clinical subt ypes and suggest that different cytokines are involved in the pathogenesis of PP MS as compared to RR and SP MS. (C) 2001 Elsevier Science B.V. All ri ghts reserved.