Abstract
In this study, we examined the acute toxicity, immunotoxicity, and cytotoxicity of bacterial magnetosomes (BMs). LD50 of BMs injected into the sublingual vein of SD rats was 62.7 mg/kg. Further studies with injection of 40 mg/kg BMs showed no significant difference between BM-treated and control rats in terms of routine blood exam results, liver and kidney function tests, organ coefficients of major organs, or Stimulation Index (SI) of lymph cells with ConA and/or LPS antigens. Histological examination of major organs from 40 mg/kg BM-treated rats showed no obvious pathological changes except for increased number of vacuoles in livers, and somewhat thicker interlobular septa in lungs. BMs showed little cytotoxic effect on H22, HL60, or EMT-6 cells. Growth of all three cells was neither inhibited nor stimulated by incubation with 9 μg/ml BMs, which also had no effect on DNA content, cell size, or cell membrane integrity.
Acknowledgements
The authors are grateful to Professor Xianda Yang, Dr Yifeng Pan, Dr Yulin Luo and Mr Yandong Zhang for helpful discussion and technical assistance.
Declaration of interest: This work was supported in part by the Chinese High Technology Research and Development Program (Grant No. 2007AA021805). The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.