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Developmental immunotoxicity (DIT) testing is centered around the concern that exposure to immunotoxicants early in development may result in enhanced susceptibility of, or unique or more persistent effects on, the immune system, in comparison to adult exposure. Developmental immunotoxicity has been the focus of numerous workshops and reviews for at least fifteen years. Most of these earlier activities have focused on both environmental chemicals and pharmaceuticals and have concluded that the best approach to DIT is to address the possible impacts of exposure during all of the critical windows of development. This article will emphasize the critical role played by exposure during the juvenile stage of development. This article will also highlight several key issues that distinguish DIT testing of pharmaceuticals. Representatives from the pharmaceutical, biotechnology, academic, and regulatory sectors (both FDA and EMA) were brought together during a two-day workshop in May 2010 to consider the current state of the science of DIT as it pertains to the testing of pharmaceuticals. It is important to emphasize at the onset that there are currently no regulatory guidelines for either drugs or nondrug chemicals specifically focused on assessment of DIT, although some general guidelines are included in both developmental and reproductive toxicity and general immunotoxicology guidance documents. [ABSTRACT FROM PUBLISHER]

While immunotoxicology evaluations are often conducted in either rodents or non-human primates, findings in standard toxicology studies may trigger additional investigations in dogs. A survey sponsored by the HESI Immunotoxicology Technical Committee, and described herein, was conducted to gather information regarding the extent and nature of immunology and immunotoxicity assessments available in the dog, and the need thereof. The survey was issued via e-mail to scientists affiliated with 39 organizations in industry and academia, including contract research organizations, academic research organizations, pharmaceutical companies, and veterinary practices. Fifteen institutions responded, including 10 biotechnology or pharmaceutical industry organizations, 4 contract research organizations, and 1 academic institution. Responses indicated that indeed, immunological assessments in dogs are necessary for research and/or toxicology purposes. The survey demonstrated that multiple types of assays are used in the dog model, including assessment of T-cell-dependent antibody responses, immunoglobulins, complement CH50, cytokines and cytokine mRNAs, lymphocyte proliferation in response to T-cell mitogens, neutrophil activation, phagocytosis, and immunophenotyping of several cell types. The survey also revealed that certain assays/endpoints are not available in the dog (complement components, NK immunophenotyping, T-cell activation and memory immunophenotyping) or require further optimization ( ex vivo cytolysis assays such as CTL and NK function, B-cell proliferation in response to LPS). In addition, the survey indicated that a greater understanding of the specificity of the available immunophenotyping reagents is needed. [ABSTRACT FROM AUTHOR]