The in vitro effects of aflatoxin B(1) on physiological functions of swine alveolar macrophages.

The toxic effects of aflatoxin B(1) (AFB(1) ) on the physiological functions of swine alveolar macrophages (SAM) were investigated. Freshly isolated SAM were incubated with various AFB(1) concentrations (1.6 × 10(-1)  - 1.6 × 10(5)  nmol/L) and time periods, and their phagocytic ability, synthesis of DNA, RNA and protein, and cell activation by lipopolysaccharide (LPS), were analysed. Results demonstrated that a significant (p < .05) reduction (60%) in Staphylococcus aureus uptaken by SAM appeared 3 hr after AFB(1) (>16 nmol/L) treatment. The synthesis of DNA, RNA and protein were markedly reduced, among which DNA and protein synthesis were affected more noticeably. The activation of SAM by LPS was significantly (p < .05) suppressed when the concentration of AFB(1) reached 1.6 × 10(3)  nmol/L. In general, most of the analysed effects were more prominent as AFB(1) concentration or incubation period increased. Taken together, AFB (1) could elicit significant adverse effects on the physiological functions of SAM. Exposure of pigs to aflatoxin-contaminated feed may increase their susceptibility to various secondary infections.