A. Noronha et al., INTERFERON-BETA DECREASES T-CELL ACTIVATION AND INTERFERON-GAMMA PRODUCTION IN MULTIPLE-SCLEROSIS, Journal of neuroimmunology, 46(1-2), 1993, pp. 145-154
Interferons (IFN) are biological molecules with anti-viral, anti-proli
ferative and immunomodulatory actions. There is evidence that IFN-gamm
a increases the frequency of exacerbations of multiple sclerosis (MS)
whereas IFN-beta may reduce their frequency. Here we present evidence
that IFN-beta significantly decreases concanavalin A (Con A)-induced p
roliferation of peripheral blood mononuclear cells (PBMC) of MS patien
ts and healthy individuals. Similar results were obtained when PBMC we
re activated through the T cell receptor (TcR) by anti-CD3 monoclonal
antibody or independently of it by phorbol ester and Ca2+ ionophore. T
hese effects of IFN-beta were also noted when IFN-gamma and IFN-beta w
ere added together. Furthermore, IFN-beta decreased proliferation when
added to cells that were already pre-activated. Activated CD4+ and CD
8+ T cells were downregulated to approximately the same extent. Analys
is of cytokine production showed that IFN-gamma production by Con A ac
tivated PBMC was increased in MS when compared to controls. IFN-beta s
ignificantly decreased IFN-gamma production in MS patients and control
individuals. Con A activated cultures treated with IFN-beta showed de
creased IL2R expression and accumulation of IL2. These results show th
at IFN-beta decreases T cell activation and IFN-gamma production in vi
tro, effects that may be beneficial in MS.