Immune System Response to Environmental Exposure

BLANCO G.A.

Environmental Health Encyclopedia

Elsevier B.V.

Lugar: Amsterdam; Año: 2007;

Immune response to environmental exposure Guillermo A. Blanco   Department of Immunology, IDEHU-National Research Council (CONICET), School of Pharmacy and Biochemistry, University of Buenos Aires (UBA), Buenos Aires, Argentina   Synopsis The immune system is among the most sensitive targets regarding toxicity of environmental pollutants. Having a critical role in maintaining human and animal health, suppression of immunological function can result in increased incidence and severity of infectious diseases. Environmental pollutants can target several mechanisms of the immune system at various cellular and subcellular levels, either during immune ontogeny, immune activation or immune effector functions. Immunotoxic mechanisms induced by representative pollutants compromising innate and adaptive immunity are discussed, such as immunotoxicity of polycyclic aromatic hydrocarbons (PAHs) and polyhalogenated-aromatic-hydrocarbons (PHAHs) induced through the arylhydrocarbon receptor, and altered production of reactive oxygen species in phagocytes due to modulation of NADPH oxidase by pesticides, metals and PAHs. Immune endpoints used in tier-based toxicity assessment are discussed together with the description of the cellular and subcellular immune processes that provide the rationale of their employment and portray their significance and limitations. Some well documented effects of metals, PAHs PHAHs and pesticides on these immune endpoints in mammals, fish and invertebrates are discussed providing a summary description of immunotoxicity by these pollutants. Functional disruption of cell mediated immunity as from pollutant-induced altered cytokine balance is also discussed particularly regarding perinatal and early life exposure.