Strain differences in sterile inflammation and immune suppression induced by acute cadmium administration in rats depend on the affected activity and tissue

Abstract

Introduction: Conflicting data (suppression, augmentation, no effect) exist concerning cadmium (Cd) effects on immune system depending on activity and tissue examined. This study investigates responses to acute Cd intoxication in three compartments (peripheral blood, spleen and lungs) in Dark Agouti (DA) and Albino Oxford (AO) rats, which are differently susceptible to variety of stimuli. Materials and Methods: Systemic (IL-6, TNF, acute phase proteins) and tissue responses [cell stress (metallothionein/MT gene expression), CD11b expression, and cytokine (IFN-γ, IL-17, IL-10) production and mRNA expression] were measured following intraperitoneal (1 mg/kg) Cd administration. Results: Cd induces systemic inflammatory response with similar intensity in both rat strains. Increase in Cd spleen content and MT expression evident in both strains (higher in DA compared to AO rats) was followed by increase in neutrophil infiltration and CD11b expression (with same intensity). Although in both strains Cd caused decreased IFN-γ, unchanged IL-17 and lower IL-10 responsiveness (compared to respective control), decrease of IFN-γ was more intense in DA compared to AO rats. In lungs of both strains increased Cd deposition and MT expression (higher in AO) as well as neutrophil infiltration and CD11b expression (greater in DA) was observed. While decreased IFN-γ was noted in both strains, lower IL-17 and IL-10 (vs. controls) were evident in DA rats solely. Conclusions: Acute Cd intoxication exerts strain-related effects (both inflammatory and immunosuppressive) depending on tissue and activity investigated, but the effects are more pronounced in DA rats.