Cytokine regulation of CD40 expression in fetal human astrocyte cultures

CD40 can participate in inflammatory processes after binding its cognate Li gand (CD40L). We found that fetal human astrocytes constitutively express C D40 mRNA and protein. Upon incubating cultures with proinflammatory cytokin es (TNF-alpha, IL-1 beta and IFN-gamma) or with lipopolysaccharide (LPS), C D40 expression was increased. No change in CD40 expression was noted in ast rocyte cultures incubated with IL-6, HIV or gp41. Astrocytes also showed in creased release of proinflammatory cytokines TNF-alpha, IL-1 beta and IL-6 after incubation with CD40L peptide. These observations suggest a role for CD40 in central nervous system (CNS) inflammation and that CD40/CD40L autoc rine or paracrine pathways may mediate this role. (C) 1999 Elsevier Science B.V. All rights reserved.