Title: Focusing on the AhR: A Potential Mechanism for Immune Effects of Prenatal Exposures

This study provides a mechanistic framework that may help us understand why this is the case.” Germolec was not involved in the current study. A new study of influenza A (shown) and TCDD provides a mechanistic framework that may help researchers understand how certain chemical exposures affect the developing immune system. © Eye of Science/Science Source Previous epidemiological studies have reported that maternal and cord blood levels of polychlorinated biphenyls and dioxins corresponded with decreased immune response to routine vaccinations3 and increased respiratory infections in children.4 The new study is thought to be the first to demonstrate that CD4+ T cells—immune cells that are critical in the creation of effective responses to both vaccinations and infections—are functionally altered after developmental exposure to a member of the same family of chemicals as those measured in the epidemiological literature. TCDD is a bioaccumulative by-product of industrial processes such as waste incineration and pesticide production.5 The compound has been shown in human and animal studies to alter transcription of genes by binding to the aryl hydrocarbon receptor (AhR).1 The researchers exposed pregnant female mice to an environmentally relevant dose of TCDD (1 μg/kg body weight). At age 6–8 weeks, the adult offspring were infected with influenza A virus. CD4+ T cells have the ability to differentiate into distinct subsets of immune cells in response to infection. Co...
Source: EHP Research - Category: Environmental Health Authors: Tags: Featured News Science Selection Dioxins and Furans Immunity Molecular Biology November 2014 Source Type: research