ENHANCED ANTIBODY-RESPONSES IN MINK (MUSTELA-VISON) EXPOSED TO DIETARY BLEACHED-KRAFT PULP-MILL EFFLUENT

Mammalian top predators such as mink (Mustela vison) that inhabit a se mi-aquatic environment may be exposed to bleached-kraft mill effluent (BKME), directly through the water, or indirectly through bioaccumulat ion of compounds in BKME via the food chain. To assess the potential i mmunotoxic effects of this exposure, the antibody response of 20 femal e mink exposed to dietary BKME for 26 weeks was studied. After 16 week s on the BKME diet, sera were collected to determine prevaccination an tibody levels against a mycobacterial antigen. Four weeks later, durin g early gestation, mink were immunized with a vaccine prepared from a culture of bacillus Calmette-Guerin (BCG). Sera were collected 6 weeks following vaccination and antimycobacterial antibody levels measured. A protein extract from cultured BCG was used as the capture antigen i n an indirect enzyme-linked immunosorbent assay to quantify mink immun oglobulin specific for BCG. Both the control and BKME-exposed mink had significantly increased BCG antibody concentrations postimmunization compared to preimmunization levels. The BKME-exposed group antibody le vels postimmunization were significantly higher (p = 0.029) than the c orresponding control group. These results demonstrate immune modulatio n from dietary BKME, which was expressed as enhanced specific antibody production in mink. A related study describes cell-mediated immunosup pression in these BKME-exposed mink, supporting the hypothesis of immu ne deviation proposed here.