NF-kappa B modulates TNF-alpha production by alveolar macrophages in asymptomatic HIV-seropositive individuals.
Local TNF-alpha production in different organs may affect HIV replication and pathogenesis. Alveolar macrophages (AMs) obtained by bronchoalveolar lavage from asymptomatic HIV-seropositive and HIV-seronegative individuals did not spontaneously release TNF-alpha, but LPS stimulation of these cells significantly increased TNF-alpha production. We tested whether NF-kappa B affects TNF-alpha production by AMs using N-tosyl-<cmd SC>l<cmd /SC> -phenylalanine chloromethylketone (TPCK) or N-benzoyl-<cmd SC>l<cmd /SC> -tyrosine ethyl ester (BTEE), which inhibit the degradation of I kappa B, or tricyclodecan-9-yl-xanthogenate-potassium (D609), which inhibits phospholipase C. Alveolar macrophages were exposed to LPS alone and with the chemical protease inhibitors TPCK, BTEE, and D609. NF-kappa B DNA binding induced by LPS treatment of AMs was inhibited by TPCK, BTEE, and D609. These agents also inhibited TNF-alpha mRNA and TNF-alpha protein production. After 24 h, the levels of TNF-alpha mRNA reached equilibrium, as assessed by RT-PCR. The levels of NF-kappa B mRNA remained constant under all conditions. The levels of I kappa B-alpha mRNA were similar after 30, 60, and 180 min, but the I kappa B-beta mRNA concentration was initially low and increased over time under all conditions. I kappa B-alpha and I kappa B-beta protein production was not affected by the chemical protease inhibitors. Our data show that TNF-alpha production by LPS-stimulated AMs from asymptomatic HIV-seropositive and -seronegative individuals is regulated via the phospholipase C pathway and by NF-kappa B DNA binding activity without obvious changes in I kappa B-alpha or I kappa B-beta protein concentrations.
Mathys
J M
JM
Department of Medicine, Division of Geographic Medicine and Infectious Diseases, Tupper Research Institute, Tufts University-New England Medical Center, Boston, MA 02111, USA.
Melanson
S M
SM
Schiffer-Alberts
D J
DJ
Ioannidis
J P
JP
Koziel
H
H
Skolnik
P R
PR
D000328:Adult; D002448:Cell Adhesion / Q000235:genetics / Q000276:immunology; D004268:DNA-Binding Proteins / Q000378:metabolism; D005260:Female; D006679:HIV Seropositivity / Q000276:immunology*; D006801:Humans; D020672:I-kappa B Proteins; D016676:Macrophages, Alveolar / Q000276:immunology* / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D000072000:NF-KappaB Inhibitor alpha; D016328:NF-kappa B / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D016133:Polymerase Chain Reaction; D020401:Primed In Situ Labeling; D011446:Prospective Studies; D012333:RNA, Messenger / Q000037:antagonists & inhibitors / Q000096:biosynthesis; D015842:Serine Proteinase Inhibitors / Q000494:pharmacology; D015398:Signal Transduction / Q000187:drug effects / Q000276:immunology; D014108:Tosylphenylalanyl Chloromethyl Ketone / Q000494:pharmacology; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors / Q000096:biosynthesis* / Q000235:genetics; D010738:Type C Phospholipases / Q000037:antagonists & inhibitors; D014443:Tyrosine / Q000031:analogs & derivatives / Q000494:pharmacology
D004268:DNA-Binding Proteins; C083487:I kappa B beta protein; D020672:I-kappa B Proteins; D016328:NF-kappa B; C000606204:NFKBIA protein, human; D012333:RNA, Messenger; D015842:Serine Proteinase Inhibitors; D014409:Tumor Necrosis Factor-alpha; D000072000:NF-KappaB Inhibitor alpha; C006716:benzoyltyrosine ethyl ester; D014108:Tosylphenylalanyl Chloromethyl Ketone; D014443:Tyrosine; D010738:Type C Phospholipases