Antiparasitic treatment of patients with P. falciparum malaria reduces the ability of patient serum to induce tissue factor by decreasing NF-kappa B activation.
Serum from patients with P. falciparum malaria at day 1 (pretherapy) induces tissue factor (TF) in cultured endothelial cells. TF induction depends on de novo transcription as shown in Nuclear Run On assays. Electrophoretic mobility shift assays demonstrated binding of AP-1 and NF-kappa B/Rel proteins to their recognition sites in the TF promotor. After therapy (day 28), stimulation of TF antigen by patient serum is reduced by 70%. When serum obtained before and after therapy was compared, a decrease of NF-kappa B activation was evident. Activation of NF-kappa B-like proteins was in part dependent on TNF alpha in patient serum, since a TNF alpha neutralizing antibody reduced induction of TF transcription and translation and induction of NF-kappa B-like proteins. Induction of TF activity was suppressed by pDTC, an inhibitor of NF-kappa B activation. When different promotor constructs of the TF gene were tested, induction was dependent upon the presence of the intact NF-kappa B-like binding site in the TF promotor. A mutant with deleted NF-kappa B, but intact AP-1 sites was not inducible. Mutation of the AP-1 sites did not prevent induction, but reduced inducibility by pretherapy serum. Therefore, NF-kappa B/Rel proteins are responsible for induction of TF transcription by pretherapy serum, but AP-1 is needed for highest inducibility. The effect of antiparasitic therapy on the induction of TF by serum from patients with complicated P. falciparum malaria is dependent on a therapy-mediated loss of activation of NF-kappa B-like proteins in post-treatment patient serum.
Bierhaus
A
A
Dept. of Medicine I, Univ. of Heidelberg, Germany.
Hemmer
C J
CJ
Mackman
N
N
Kutob
R
R
Ziegler
R
R
Dietrich
M
M
Nawroth
P P
PP
D000962:Antimalarials / Q000494:pharmacology* / Q000627:therapeutic use; D001483:Base Sequence; D001665:Binding Sites; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000187:drug effects / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects*; D017930:Genes, Reporter; D006801:Humans; D016778:Malaria, Falciparum / Q000097:blood* / Q000188:drug therapy; D008969:Molecular Sequence Data; D016296:Mutagenesis; D016328:NF-kappa B / Q000037:antagonists & inhibitors* / Q000502:physiology; D011401:Promoter Regions, Genetic; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000235:genetics; D012045:Regulatory Sequences, Nucleic Acid; D013925:Thromboplastin / Q000096:biosynthesis* / Q000235:genetics; D018808:Transcription Factor AP-1 / Q000378:metabolism; D014158:Transcription, Genetic / Q000187:drug effects; D014162:Transfection; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis / Q000502:physiology*; D014471:Umbilical Veins
D000962:Antimalarials; D016328:NF-kappa B; D011993:Recombinant Fusion Proteins; D018808:Transcription Factor AP-1; D014409:Tumor Necrosis Factor-alpha; D013925:Thromboplastin