IN-VITRO CYTOKINE, SCD23 AND IGG SECRETION IN MULTIPLE-SCLEROSIS

Synthesis of IgG by peripheral blood mononuclear cells from patients w ith multiple sclerosis (MS) and with other neurological diseases and f rom healthy controls was induced by Pokeweed mitogen (PWM) in short-te rm cultures. As expected, MS patients produced more immunoglobulin (Ig ) G and had a higher percentage of 'high responders' to PWM stimulatio n as compared to controls. Interleukin (IL)-4 was undetectable in all samples. IL-6 and tumor necrosis factor (TNF)-alpha synthesis was indu ced by PWM stimulation in all groups, but MS patients showed the most significant increase of both cytokines. Interestingly, only MS patient s showed a significant increase of the soluble form of CD23 receptor ( sCD23). Moreover, only sCD23 levels correlated with in vitro IgG produ ction in MS patients. The levels of IL-6, TNF-alpha, sCD23 were greate r in high responders compared to low responders in all groups. The mea n value of each molecule, however, did not differ significantly among overall groups. A highly significant difference was reported for sCD23 in MS patients. We suggest that sCD23, also known as B cell growth fa ctor, may play a role in the well-documented phenomenon of in vitro Ig G hypersynthesis in MS patients, adding support to the concept of B ce ll up-regulation in the peripheral blood of these patients.