TY - JOUR
T1 - Tetrabromobisphenol A has immunosuppressive effects on human natural killer cells
AU - Kibakaya, Esther Caroline
AU - Stephen, Krishna
AU - Whalen, Margaret M.
N1 - Funding Information:
This research was supported by Grant 2S06GM-08092-34 from the National Institutes of Health.
PY - 2009/12
Y1 - 2009/12
N2 - Human natural killer (NK) cells are lymphocytes that destroy tumor cells, virally-infected cells, and antibody-coated cells. Tetrabromobisphenol A (TBBPA) is used both as a reactive and as an additive flame retardant in a variety of materials and appears to contaminate the environment. TBBPA has been found in human blood samples and if it interferes with NK cell function, this could increase the risk of tumor development and/or viral infection. The present study examines the effects of exposure to various concentrations of TBBPA for 24hr, 48hr, and 6 days on the lytic function, tumor-target-binding function, and ATP levels of NK cells. These same parameters were also monitored in NK cells that were exposed to TBBPA for 1h followed by 24hr, 48hr, and 6 days in TBBPA-free media. A 24-h exposure of NK cells to 5 μM TBBPA caused a >95% decrease in NK lytic function, a 70% decrease in binding function, and a 34% decrease in ATP levels in NK cells. Exposure to 2.5 μM TBBPA for 24h decreased lytic function by 76%, binding function by 20%, and had no effect on ATP levels. Exposure of NK cells to 5 μM TBBPA for 1h followed by 24h in TBBPA-free media caused a progressive and persistent loss of lytic function (41%) while not affecting either binding ability or ATP levels. The results indicate that TBBPA exposures decrease the lytic function of human NK cells and that an initial brief (1hr) exposure can cause a progressive loss of function. In addition, the data also indicate that TBBPA-induced loss of NK lytic function can occur at a concentration of TBBPA that does not affect target-binding ability and ATP levels of NK cells.
AB - Human natural killer (NK) cells are lymphocytes that destroy tumor cells, virally-infected cells, and antibody-coated cells. Tetrabromobisphenol A (TBBPA) is used both as a reactive and as an additive flame retardant in a variety of materials and appears to contaminate the environment. TBBPA has been found in human blood samples and if it interferes with NK cell function, this could increase the risk of tumor development and/or viral infection. The present study examines the effects of exposure to various concentrations of TBBPA for 24hr, 48hr, and 6 days on the lytic function, tumor-target-binding function, and ATP levels of NK cells. These same parameters were also monitored in NK cells that were exposed to TBBPA for 1h followed by 24hr, 48hr, and 6 days in TBBPA-free media. A 24-h exposure of NK cells to 5 μM TBBPA caused a >95% decrease in NK lytic function, a 70% decrease in binding function, and a 34% decrease in ATP levels in NK cells. Exposure to 2.5 μM TBBPA for 24h decreased lytic function by 76%, binding function by 20%, and had no effect on ATP levels. Exposure of NK cells to 5 μM TBBPA for 1h followed by 24h in TBBPA-free media caused a progressive and persistent loss of lytic function (41%) while not affecting either binding ability or ATP levels. The results indicate that TBBPA exposures decrease the lytic function of human NK cells and that an initial brief (1hr) exposure can cause a progressive loss of function. In addition, the data also indicate that TBBPA-induced loss of NK lytic function can occur at a concentration of TBBPA that does not affect target-binding ability and ATP levels of NK cells.
KW - ATP
KW - Lytic function
KW - NK cells
KW - Tetrabromobisphenol A
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U2 - 10.3109/15476910903258260
DO - 10.3109/15476910903258260
M3 - Article
C2 - 19908946
AN - SCOPUS:70450216534
SN - 1547-691X
VL - 6
SP - 285
EP - 292
JO - Journal of Immunotoxicology
JF - Journal of Immunotoxicology
IS - 4
ER -