Effects of Gestational and Lactational Exposure to Organochlorine Compounds on Cellular, Humoral, and Innate Immunity in Swine

Abstract

Few studies have characterized the immunotoxic potential of complex mixtures of organochlorines (OCs) that bear environmental relevance. We monitored immune parameters in male piglets exposed in utero and through lactation to an OC mixture which was designed to approximate that found in the traditional diet of Arctic aboriginal populations. Prepubertal sows were administered orally either corn oil (control group) or the OC mixture in increasing doses (low, medium, and high). The sows were inseminated with the semen from an untreated boar and OC treatment was continued throughout gestation and lactation (21 days). Blood was collected from the sows at delivery and monthly from piglets until 8 months of age for the determination of plasma OC concentrations and parameters of innate, cellular, and humoral immunity. Treatment with the OC mixture had no dose-dependent effect on the proportion of CD4+ and CD8+ T-cell subsets, and did not modulate the functional activity of the complement component C2. The proportion of CD4+CD8+ cells, CD8+DR+ cells, and the mitogenic lymphoproliferative response increased in OC-treated, 4-month-old piglets. At 6 months, the lymphoproliferative response to mitogen and the proportion CD4+CD8+ cells were still elevated in the OC-treated piglets, but the proportion of CD8+DR+ cells was decreased as compared to the controls. Animals in the high-dose group also exhibited a slight increase in polymorphonuclear leukocyte phagocytic activity at 8 months of age. Furthermore, the high dose decreased the antibody response to Mycoplasma hyopneumoniae. Our results indicate that developmental exposure to an environmentally relevant OC mixture alters the immune function in swine.

Prenatal exposure to an environmentally relevant mixture of Canadian Arctic contaminants decreases male reproductive function in an aging rat model

“…These symptoms were observed for all the aged OC males. To support this hypothesis, prenatal exposure to the Arctic OC mixture has been reported to depress immune responses in swine 32 . Similarly, prenatal exposure to OC in Inuit populations is correlated with a high level of infection and respiratory diseases 33 .…”