title: Modulation of immunocompetent cell populations by benzo[a]pyrene.
abstract: These studies examined the cellular targets of benzo[a]pyrene (BaP)-induced immunomodulation. The immunocompetence of murine mononuclear leukocytes was evaluated following in vivo exposure to BaP. In vitro cell separation and reconstitution techniques were used to evaluate T-dependent antibody (TDAb) production and delineate the immunomodulatory events. Reconstitution of cultures using combinations of adherent and nonadherent cell populations from BaP- and vehicle-treated mice demonstrated that both of these populations were sensitive to the immunomodulatory effects of BaP. Examination of the adherent cell population demonstrated that low numbers of BaP-exposed accessory cells enhanced in vitro TDAb responses. These responses were greater than those observed for analogous cultures containing vehicle-exposed accessory cells. Recombination of separated B cells and T cells from vehicle- or BaP-treated mice in cultures containing normal adherent cells demonstrated that both B cells and T cells were sensitive to the effects of BaP. Cultures containing BaP-exposed cell populations were incapable of supporting control level antibody responses. The results indicate that in vivo BaP exposure induces immunomodulation through effects on macrophages, B cells, and T cells.
authors.affiliation: Department of Microbiology and Immunology, Medical College of Virginia, Virginia Commonwealth University, Richmond 23298-0001.
authors.forename: R H
authors.initials: RH
authors.lastname: Blanton
authors.forename: M J
authors.initials: MJ
authors.lastname: Myers
authors.forename: P H
authors.initials: PH
authors.lastname: Bick
mesh_terms: D000818:Animals; D000917:Antibody Formation / Q000187:drug effects; D000938:Antigen-Presenting Cells / Q000187:drug effects; D001564:Benzo(a)pyrene / Q000494:pharmacology*; D005260:Female; D007376:Interleukin-2 / Q000096:biosynthesis; D007958:Leukocyte Count; D008214:Lymphocytes / Q000187:drug effects* / Q000276:immunology; D008264:Macrophages / Q000187:drug effects* / Q000276:immunology; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL
chemical_list: D007376:Interleukin-2; D001564:Benzo(a)pyrene