Upregulation of intercellular adhesion molecule-1 (ICAM-1) on rat Schwann cells in vitro: comparison of interferon-gamma, tumor necrosis factor-alpha and interleukin-1.

We investigated the expression and upregulation of intercellular adhesion molecule-1 (ICAM-1) in cultures of neonatal rat Schwann cells. Unstimulated cells expressed little or no ICAM-1 as determined by binding of monoclonal antibody to rat ICAM-1 using qualitative and quantitative immunofluorescence. ICAM-1 positive cells when present represented a very small minority (<4%) of Schwann cells. Incubation with recombinant rat interferon-gamma, recombinant rat IL-1beta, recombinant rat tumor necrosis factor-alpha, unfractionated rat cytokines but not purified porcine transforming growth factor-beta or recombinant rat IL-2, resulted in upregulation of ICAM-1 on Schwann cells. Different kinetics were noted for ICAM-1 upregulation by the different recombinant and purified cytokines. The upregulation of ICAM-1 on Schwann cells may be important in inflammatory diseases of the peripheral nervous system as well as in myelination and remyelination.