The effect of IL-8 on the in vitro locomotion of human IL-2-activated natural killer (IANK) cells was studied. It was observed that IL-8 induces chemokinesis in these cells, as determined by their migration in modified Boyden chambers. Bacterial toxins such as cholera toxin or pertussis toxin inhibited IL-8-induced chemokinetic activity, suggesting the involvement of guanine nucleotide-binding (G) proteins in IL-8 signal transduction in these cells. Pertussis toxin ADP-ribosylates a 39-kDa protein, whereas cholera toxin ADP-ribosylates a 43- to 45-kDa protein. Pretreatment of IANK cell membranes with 0.01 or 0.1 ng/ml of IL-8 and/or 5 μM GTP-γS did not affect pertussis toxin- or cholera toxin-dependent ADP-ribosylation. Western blot analysis showed that IANK cell membranes possess one G(i) (39 kDa), two G(s) (43 kDa and 45 kDa), and one G(o) (39 kDa). Pretreatment of IANK cell membranes with concentrations between 0.001 to 1.0 ng/ml of IL-8 resulted in the disappearance of the 39 kDa G(o), but not G(i) or G(s) protein(s), suggesting that IL-8 receptors expressed on IANK cells are coupled to G(o). Various concentrations of IL-8 enhanced the binding of GTP-γ35S to IANK cell membranes, which further indicates the coupling of G proteins to IL-8 receptors in IANK cells.
|Original language||English (US)|
|Number of pages||11|
|Journal||Journal of Immunology|
|State||Published - Jan 1 1993|
ASJC Scopus subject areas
- Immunology and Allergy