Biocompatibility of bacterial magnetosomes: Acute toxicity, immunotoxicity and cytotoxicity

Abstract

In this study, we examined the acute toxicity, immunotoxicity, and cytotoxicity of bacterial magnetosomes (BMs). LD(50) 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 microg/ml BMs, which also had no effect on DNA content, cell size, or cell membrane integrity.

Fluorescence imaging and targeted distribution of bacterial magnetic particles in nude mice

“…Following injection into tail vein, BMPs were found to be accumulated in lungs and liver, but not in other locations. This finding was inconsistent with the results of our previous study of tissue distribution and host elimination following injection of BMPs in Sprague-Dawley rats in which BMPs displayed targeted distribution to liver (Sun et al 2009(Sun et al , 2010. Distribution of particles following i.v.…”

“…Their biocompatibility and biodistribution are, in general, not well understood. We previously described body tissue distribution and host tissue elimination following administration of BMPs into the bloodstream of rats (Sun et al 2009(Sun et al , 2010 and in vitro cytotoxicity of BMPs in mouse fibroblasts (Li et al 2007a).…”

Magnetotactic bacteria for cancer therapy

“…Magnetosomes are enclosed by a lipid bilayer and specific soluble and trans-membrane proteins helps magnetosomes to attain biocompatibility. On the other hand, toxic properties of magnetosomes might be due to: (i) their nano-scale size, which leads to deposition and aggregation of nanoparticles in the body (Sun et al 2010), (ii) impurities (particularly proteins, nucleic acids, and polysaccharides) associated with magnetosomes during extraction from cells, and their immunotoxicity, and (iii) membrane-containing proteins (Jevprasesphant et al 2003;Grunberg et al 2004).…”

The Effect of Sonication on Acoustic Properties of Biogenic Ferroparticle Suspension

“…Nanometersized magnetosomes are of great interest in biotech-nology since they have a large surface area which can be used for anchoring relatively large amounts of specific molecules and can be easily manipulated using an external magnetic field (Araujo et al, 2015). Unfortunately, it is difficult to obtain magnetosomes in large quantities (Sun et al, 2010) and therefore their properties have not been sufficiently characterised so far and no commercial application has as yet been recognized. Recently, a significant progress has been achieved in synthesis of magnetic particles by various bacterial strains.…”

“…Biogenically-produced magnetosomes present unique features that are difficult to obtain through the chemical synthesis of abiotically-produced magnetic nanocrystals (Araujo et al, 2015). Magnetosome particles are organelles consisting of magnetite crystals enclosed by the phospholipid membrane that offer a high degree of biocompatibility (Ceyhan et al, 2006;Sun et al, 2010). In most magnetosomes, the mineral core of magnetosomes consists of magnetic iron oxide (Fe 3 O 4 ).…”