EFFECTS OF INTERLEUKIN-1 AND INTERLEUKIN-6 ON METALLOTHIONEIN AND AMYLOID PRECURSOR PROTEIN EXPRESSION IN HUMAN NEUROBLASTOMA-CELLS - EVIDENCE THAT INTERLEUKIN-6 POSSIBLY ACTS VIA A RECEPTOR DIFFERENT FROM THE80-KDA INTERLEUKIN-6 RECEPTOR

Since immunohistochemical studies indicated the presence of interleuki n-6 in the cortices of patients with Alzheimer's disease, we were inte rested in the eventual biological effects of this cytokine on neuronal cells. We found that interleukin-6 and interleukin-1 induced metallot hionein expression in a human neuronal (SH-SY5Y neuroblastoma) cell li ne. In contrast to metallothionein, amyloid precursor protein expressi on was unaffected by both cytokines. When searching in the same cell l ine for the expression of the classical 80-kDa interleukin-6 binding p rotein, which is part of the dimeric interleukin-6 receptor, we were u nable to detect the respective mRNA. Our findings either indicate that the interleukin-6 receptor in these cells is expressed in extremely l ow levels or that interleukin-6 may act upon neuronal cells via a diff erent, yet unknown neuronal receptor.