Lipopeptides are effective stimulators of tyrosine phosphorylation in human myeloid cells.
Synthetic lipopeptide analogues of the N-terminus of bacterial lipoprotein are effective activators of macrophages, neutrophils and lymphocytes. We studied the effect of the lipopeptide N-palmitoyl-S-[2,3-bis(palmitoyloxy)-(2RS)-propyl]- (R)-cysteinyl-(S)-seryl-(S)-lysyl-(S)-lysyl-(S)-lysyl-(S)-lysine [Pam3Cys-Ser-(Lys)4] on tyrosine phosphorylation in dibutyryl-cyclic-AMP-differentiated HL-60 cells, using anti-phosphotyrosine antibodies. Pam3Cys-Ser-(Lys)4 concentration-dependently stimulated tyrosine phosphorylation of 100/110 kDa and 60 kDa proteins and, to a lesser extent, of 55 kDa and 70/75 kDa proteins. Half-maximal and maximal effects were observed at concentrations of 1-6 and 5-50 micrograms/ml respectively. The lipopeptide-induced increase in phosphorylation was rapid and transient, with a peak response after 30-60 s. The lipopeptide (2S)-2-palmitoylamino-6-palmitoyloxymethyl-7-palmitoyloxy heptanoyl-Ser-(Lys)4 [Pam3Ahh-Ser-(Lys)4] was as potent as Pam3Cys-Ser(Lys)4, whereas (2S,6S)-2-palmitoylamino-6,7-bis(palmitoyloxy)heptanoyl++ +-Ser-(Lys)4 [Pam3Adh-Ser-(Lys)4] and Pam3Cys-Ser-Gly did not induce tyrosine phosphorylation. Lipopeptide-induced tyrosine phosphorylation was not affected by treatment of cells with pertussis toxin. Neither phorbol 12-myristate 13-acetate nor A23187 induced tyrosine phosphorylation in dibutyryl-cyclic-AMP-differentiated HL-60 cells. In HL-60 promyelocytes, Pam3Cys-Ser-(Lys)4 had no effect on tyrosine phosphorylation, whereas the lipopeptide also induced tyrosine phosphorylation in 1,25-dihydroxyvitamin-D3-differentiated HL-60 cells and in human neutrophils. These results show that lipopeptides are effective stimulators of tyrosine phosphorylation in mature human myeloid cells.
Offermanns
S
S
Institut für Pharmakologie, Freie Universität Berlin, Federal Republic of Germany.
Seifert
R
R
Metzger
J W
JW
Jung
G
G
Lieberknecht
A
A
Schmidt
U
U
Schultz
G
G
D015153:Blotting, Western; D003994:Bucladesine / Q000494:pharmacology; D002454:Cell Differentiation / Q000187:drug effects; D002478:Cells, Cultured; D004591:Electrophoresis, Polyacrylamide Gel; D019833:Genistein; D006801:Humans; D007529:Isoflavones / Q000494:pharmacology; D008074:Lipoproteins / Q000494:pharmacology*; D009504:Neutrophils / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D037342:Pertussis Toxin; D010766:Phosphorylation / Q000187:drug effects; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014443:Tyrosine / Q000378:metabolism*; D010566:Virulence Factors, Bordetella / Q000494:pharmacology
D007529:Isoflavones; D008074:Lipoproteins; D010566:Virulence Factors, Bordetella; C061108:N-palmitoyl-S-(2,3-bis(palmitoyloxy)propyl)cysteinyl-seryl-lysyl-lysyl-lysyl-lysine; D014443:Tyrosine; D003994:Bucladesine; D019833:Genistein; D037342:Pertussis Toxin; D013755:Tetradecanoylphorbol Acetate