title: Polychlorinated biphenyl mixtures (Aroclors) inhibit LPS-induced murine splenocyte proliferation in vitro.
abstract: The immune system is believed to be a sensitive indicator for adverse polychlorinated biphenyl (PCB)-induced health effects. Four commercial PCB mixtures (Aroclors) or six individual PCB congeners were evaluated for their effect on splenocyte viability and lipopolysaccharide (LPS)-induced splenocyte proliferation in vitro in two strains of mice, C57B1/6 (high affinity aromatic hydrocarbon receptor (AhR) complex) and DBA/J (low affinity AhR complex). All four Aroclors, the selected individual noncoplanar congeners, or two tertiary mixtures containing one congener from each class significantly decreased the in vitro LPS-induced proliferation of murine splenocytes in either strain of mice without inducing a significant decrease in viability. In contrast, selected individual coplanar or mono-ortho-coplanar congeners did not inhibit splenocyte proliferation or viability at any concentration. These results suggest that mixtures of PCBs and/or congener class (specifically, noncoplanar congeners) may be more highly immunotoxic than individual planar and mono-ortho-coplanar congeners alone. Thus, this in vitro assay has revealed a more complex pattern of immunotoxicity of Aroclors versus individual congeners than has previously been reported or anticipated based on both in vivo derived immunotoxic data and standard comparisons to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). These results have important practical significance since mixtures of PCB congeners were used industrially and now contaminate the environment.
authors.affiliation: Department of Microbiology and Immunology, Medical University of South Carolina, Charleston 29425, USA.
authors.forename: A S
authors.initials: AS
authors.lastname: Stack
authors.forename: S
authors.initials: S
authors.lastname: Altman-Hamamdzic
authors.forename: P J
authors.initials: PJ
authors.lastname: Morris
authors.forename: S D
authors.initials: SD
authors.lastname: London
authors.forename: L
authors.initials: L
authors.lastname: London
mesh_terms: D000818:Animals; D001140:Aroclors / Q000737:chemistry / Q000633:toxicity*; D015153:Blotting, Western; D002455:Cell Division / Q000187:drug effects; D004785:Environmental Pollutants / Q000032:analysis / Q000633:toxicity*; D005260:Female; D000922:Immunotoxins / Q000633:toxicity*; D066298:In Vitro Techniques; D008070:Lipopolysaccharides / Q000037:antagonists & inhibitors* / Q000633:toxicity; D051379:Mice; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D012485:Salmonella typhi; D013154:Spleen / Q000166:cytology* / Q000187:drug effects / Q000276:immunology; D013329:Structure-Activity Relationship
chemical_list: D001140:Aroclors; D004785:Environmental Pollutants; D000922:Immunotoxins; D008070:Lipopolysaccharides