ISSN:
1432-2013
Keywords:
Key words cAMP
;
gp41
;
G protein
;
IL-10
;
NF-κB
;
Peripheral blood mononuclear cells
;
S6 kinase
;
Signal transduction
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Abstract. Our previous results show that recombinant gp41 (aa565–647), the extracellular domain of HIV-1 transmembrane glycoprotein, stimulates interleukin-10 (IL-10) production in human monocytes. The signal cascade transducing this effect is not yet clear. In this study, we examined whether gp41-induced IL-10 up-regulation is mediated by the previously described synergistic activation of cAMP and NF-κB pathways. gp41 induced cAMP accumulation in monocytes in a time- and concentration-dependent manner and the adenylate cyclase inhibitor SQ 22536 suppressed gp41-induced IL-10 production in monocytes. In contrast, gp41 failed to stimulate NF-κB binding activity in as much as no NF-κB bound to the main NF-κB-binding site 2 of the IL-10 promoter after addition of gp41. We also examined the involvement of other signal transduction pathways. Specific inhibitors of p70S6-kinase (rapamycin), and Gi protein (pertussis toxin), prevented induction of IL-10 production by gp41 in monocytes, while inhibitors of the phosphatidylinositol 3-kinase (PI 3-kinase) (wortmannin) and mitogen-activated protein kinase (MAPK) pathway (PD 98059) did not. Thus HIV-1 gp41-induced IL-10 up-regulation in monocytes may not involve NF-κB, MAPK, or PI 3-kinase activation, but rather may operate through activation of adenylate cyclase and pertussis-toxin-sensitive Gi/Go protein to effect p70S6-kinase activation.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s004240050815
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