Protocols for the study of immunotoxicity: A review

To study the potential effects of toxic agents on immune system function and/or integrity, methods that can be validated in animal models and which provide results capable of being extrapolated to human health need to be developed. This damage can also be evaluated in key species within trophic webs or in those that are biologically important per se. Absence of general agreement as to the biomarkers to be used in the field of Immunotoxicity reveals the need for definite protocols associated with the complexities of immune response. Three types of strategies are described; rather than being mutually exclusive, they are parts of an integral whole and their results run the gamut from the simple to the complex. The basic type I strategies includes evaluations of lymphoid cells and related blood chemistry. The extended type I strategies comprises the function of subpopulations involved in cellular and humoral response. Type II includes assays for T cell-dependent and independent antigens, B cells, cellular immunoreactivity and, most of all, co-exposure to infectious contagious agents or tumoral cells. The metabolic type III and histopathologic type III strategies have to do with immune system organs. Nevertheless, current evidence indicates that immune system damage may often be modulated by changes associated with the bioactivation of toxic agents in non lymphoid organs, which can alter immune system function at the pre- and post-transcriptional level.