PCB congeners and the murine immune system: The capacity of isolated congeners to decrease spleen specific antibody forming cell numbers varies with the toxic equivalence factors of the congeners.
Polychlorinated biphenyl (PCB) congeners 77 (3,3',4,4'-tetrachlorinated biphenyl) and 118 (2,3',4,4',5-pentachlorinated biphenyl) were given by gavage as a single dose to female C57BL/6J mice. The dose levels tested were 25 and 100 mumol/kg body weight for PCB-77, and 250 and 800 mumol/kg for PCB-118. 2 days after dosing, the mice were either immunized with sheep red blood cells (SRBC) or they were killed and their livers were removed for determination of ethoxyresorufin-O-deethylase (EROD) activity, and their spleens were removed for assays of natural killer (NK) cells and mitogen stimulation assays. The immunized mice were killed 4 days after immunization, and their spleens were removed for determination of the number of plaque forming cells. Both congeners induced a reduction in anti-SRBC forming cells and an increase in liver microsomal EROD activity, their relative potencies being of the same order of magnitude as reported for their general toxicity. No effect was observed on NK cell activity or on the response to mitogens in vitro.
Dahlman
H J
HJ
Department of Environmental Medicine, National Institute of Public Health, Oslo, Norway; Institute of Biochemistry, University of Oslo, Norway.
Gaarder
P I
PI
Løvik
M
M
Alexander
J
J
Becher
G
G
Bergman
A
A