Hemozoin "knobs" in Opisthorchis felineus infected liver.

BACKGROUND: Hemozoin is the pigment produced by some blood-feeding parasites. It demonstrates high diagnostic and therapeutic potential. In this work the formation of co-called hemozoin "knobs" - the bile duct ectasia filled up by hemozoin pigment - in Opisthorhis felineus infected hamster liver has been observed. METHODS: The O. felineus infected liver was examined by histological analysis and magnetic resonance imaging (MRI). The pigment hemozoin was identified by Fourier transform infrared spectroscopy and high resolution electrospray ionization mass spectrometry analysis. Hemozoin crystals were characterised by high resolution transmission electron microscopy. RESULTS: Hemozoin crystals produced by O. felineus have average length 403 nm and the length-to-width ratio equals 2.0. The regurgitation of hemozoin from parasitic fluke during infection leads to formation of bile duct ectasia. The active release of hemozoin from O. felineus during in vitro incubation has also been evidenced. It has been shown that the hemozoin knobs can be detected by magnetic resonance imaging. CONCLUSIONS: In the paper for the first time the characterisation of hemozoin pigment extracted from liver fluke O. felineus has been conducted. The role of hemozoin in the modification of immune response by opisthorchiasis is assumed.

Characterization of the novel chemically modified fungal polysaccharides as the macrophage stimulators.

By means of carboxymethylation, a novel water-soluble carboxymethyl chitin-glucan (CM-CG) was prepared from the mycelium of Aspergillus niger, and its ability to stimulate macrophages was assessed and compared to that of the previously studied carboxymethylated glucan (CMG) from the yeast Saccharomyces cerevisiae. It was demonstrated that single intraperitoneal (i.p.) administration of CMG and CM-CG to the CBA mice led to a significant increase of leukocyte number. At the same time, the number of monocytes in the bone marrow was increased to more than two-fold. Application of both polysaccharides also resulted in the augmented number of liver macrophages and to the rise of their content of the secondary lysosomes. A markedly enhanced carbon clearance was observed as well as the increased release of tumor necrosis factor-alpha by the peritoneal macrophages indicating their amplified phagocytic activity. The effect of CM-CG in these experiments was ca. 1.7 times higher than that of CMG. Administration of both polysaccharides also led to the elevated level of free acid phosphatase in liver homogenate, implying labilization of the lysosomes. Increased serum chitotriosidase also indicated increased macrophage activity. The results obtained indicate similar in vivo macrophage stimulation activity of both applied fungal polysaccharides and suggest their potential clinical use as non-toxic natural compounds.