The inhibitory effect of interferon-alpha on the serotonin-induced impairment of human NK cell activity in whole blood.
Serotonin (5-HT) at a concentration of 10(-4) to 10(-10) M impaired the cytotoxicity of human natural killer cells in whole blood. 5-HT added at the onset of the short-term cytotoxic assay had a pronounced inhibitory effect. It is very likely that the 5-HT2 receptor is involved in the inhibition of cytotoxicity because ketanserin, an inhibitor of the 5-HT2 receptor, partially prevented the effect of 5-HT. Treatment with 10(2)-10(4) IU/ml of interferon-alpha before or after the application of 5-HT decreased its inhibitory effect on the cytotoxicity. Radioligand binding studies revealed that the antagonistic effect of interferon was not due to the competition for the 5-HT2 receptors. Cycloheximide, an inhibitor of protein synthesis, did not block the suppression of natural killer activity by 5-HT, but it exerted a blocking effect on the acquisition of resistance to 5-HT induced by interferon.
Garssadi
S I
SI
Institute of Microbiology, Albert Szent-Györgyi Medical University, Szeged, Hungary.
Mándi
Y
Y
Régely
K
K
Taródi
B
B
Béládi
I
I
D002478:Cells, Cultured; D003513:Cycloheximide / Q000494:pharmacology; D003602:Cytotoxicity, Immunologic / Q000187:drug effects; D006801:Humans; D016898:Interferon-alpha / Q000494:pharmacology*; D007650:Ketanserin / Q000494:pharmacology*; D007694:Killer Cells, Natural / Q000187:drug effects*; D015213:Neuroimmunomodulation / Q000502:physiology*; D011985:Receptors, Serotonin / Q000187:drug effects / Q000502:physiology; D012701:Serotonin / Q000494:pharmacology*
D016898:Interferon-alpha; D011985:Receptors, Serotonin; D012701:Serotonin; D007650:Ketanserin; D003513:Cycloheximide