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  • Author: G. Hrčková x
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Summary

Intraperitoneal infection with larvae of cestode Mesocestoides vogae offers the opportunity to study dynamic changes in the proportion and functions of individual cell types under a direct influence of parasites. The phagocytic activity is one of the basic effector functions of professional phagocytes and receptor-mediated uptake is a central in implementation of inflammatory responses. Present study extends information on this issue by exploring several phagocytosis pathways in M. vogae-induced myelo-monocytic cells. In addition, we analyzed proportions of morphologically distinct phenotypes within macrophage compartments after oral inoculation of larvae to mice. In gradually elevated population of peritoneal exudate cells, monocytes/ macrophages and giant cell were dominant cell types from day 21 p.i. Phagocytic activity of these cells had biphasic behaviour for both opsonin-dependent and independent pathways, whereas uptake by multinucleated macrophages was profoundly reduced. Highly elevated proportions of activated phagocytic cells were found from day 7 to 14 p.i., regardless particle type (latex beads, HEMA, liposomes) and opsonisation. Source of opsonins used for coating of liposomes suggested higher expression of complement receptors than Fc receptors on these cells, although the uptake of non-opsonized liposomes had different kinetics and was very high by activated cells early p.i. Present data indicate that early recruited macrophages/monocytes attain pro-inflammatory functions as indicated by highly elevated phagocytosis of immunologically inert particles as well as opsonized liposomes what is down-regulated once larvae start to proliferate in the peritoneal cavity, suggesting the role of parasite-derived molecules in modulation of this key phagocytes function.

Summary

The metacestode stage of the tapeworm Mesocestoides vogae (M. vogae) has the ability of asexual growth in the peritoneal cavity of rodents and other intermediate hosts without restriction. Early immunological events have decisive role in the establishment of infection. In the present study we investigated the kinetic of myeloid and lymphoid cell populations and the proportions of cells undergoing apoptosis in peritoneal cavities of mice within the first month after oral infection with M. vogae larvae. Proportions of cell phenotypes and apoptotic cells were examined by flow cytometry and by microscopical analysis of cells following May/Grünwald staining and fluorescent stain Hoechst 33234, respectively. Total numbers of peritoneal cells increased and their distribution changed towards accumulation of myelo-monocytic cell lineage in the account of reduced proportions of lymphoid cells. CD4+ T cell subpopulations were more abundant than CD8+ and their proportions elevated within two weeks post infection (p.i.) which was followed by a significant decline. Expression level of CD11c marker on myelo-monocytic cells revealed phenotype heterogeneity and proportions of cells with low and medium expression elevated from day 14 p.i. along with concurrent very low presence of CD11chigh phenotype. Lymphoid cell population was highly resistant to apoptosis but elevated proportions of myeloid cells were in early/late stage of apoptosis. Apoptosis was detected in a higher number of adherent cells from day 14 p.i. onwards as evidenced by nuclear fluorescent staining. By contrast, cells adherent to larvae, mostly macrophages and eosinophils, did not have fragmented nuclei. Our data demonstrated that apoptosis did not account for diminished population of peritoneal lymphoid cells and substantial proportions of myeloid cells seem to be more susceptible to apoptotic turnover in peritoneal cavity of mice with ongoing M. vogae infection, suggesting their important role in the host-parasite interactions.

Abstract

Aims

Silymarin (SIL), a mixture of phenolic compounds, has a pleiotropic mode of action on various cell types, including immune cells. In this study, we investigated the concentration-dependent effect of SIL on proliferation of concanavalin A (CoA)-stimulated mouse spleen T lymphocytes, their viability, and secretion of IFN-g and IL-4 cytokines ex vivo in relation to gene expressions of transcription factors nuclear factor kappa B and Foxp3. In addition, metabolic activity of T cells was determined as changes in the mitochondrial membrane potential and apoptosis.

Material/Methods

Isolated splenocytes were stimulated with lectin CoA and treated with SIL atthe concentrations of 5, 10, 20, and 40 μg/ml for 70 h and unstimulated cells served as the control. Cultures of splenocytes were evaluated for proliferation index following BrdU incorporation and viability of cells after trypan blue staining. Gene expressions of transcription factors and cytokines were assessed using real-time PCR, whereas ELISA test was applied to measure cytokine secretion. Mitochondrial membrane potential and apoptosis were determined by flow cytometry.

Results

We demonstrated that CoA-activated mouse spleen T lymphocytes show different susceptibilities to low (£10 μg/ml) and higher (20 and 40 μg/ml) SIL concentrations. Low concentrations resulted in increased proliferation, cytokine secretion, and mitochondrial membrane potential and reduced transition of cells to apoptosis. High concentration of SIL had the opposite effect without exerting significant cytotoxicity and upregulated genes for cytokines and transcription factors on mRNA level. It is possible that individual subpopulations of T cells induced by CoA were differentially affected by the various SIL concentrations and the dose of 40 μg/ml had the profound suppressive effect. This correlated with the highest expression of Foxp3 factor, indicating that this dose stimulated preferential differentiation to Tregs lymphocytes.

Conclusions

Treatment with suitable doses of SIL can provide potential benefits in the modulation of host immune functions in various diseases.

Summary

Cathaemasia hians is an obligate trematode parasite of Black storks that are on the List of protected birds in Europe. In the present study, adult trematodes were isolated from the Black stork post mortem and morphological study revealed C. hians species. In total, 10 worms were found in the oesophagus and the ventriculus of the bird. Histopathological examination of the tissue samples of oesophagus, proventriculus and ventriculus was performed on paraffin sections using a set of staining procedures. The sporadic lesions were seen in the tela submucosa of oesophagus containing connective tissue mast cells, eosinophils and heterophils and some foci were surrounded by the fibrous tissue. In addition, a few inflammatory nodules had larval-like material inside, probably being of the same species. There were no visible morphological alterations in the epithelial layer of lamina propria mucosae of proventriculus, rich in goblet cells as well as in the tela submucosa. Majority of trematodes were localized in the ventriculus, where the lamina propria mucosae was damaged or disrupted sporadically. In these sites, in the tela submucosa, a various food-originated inorganic/organic material and eggs of C. hians were deposited, stimulating a weak inflammatory response. Nodules containing larvae were not observed in any of ventriculus tissue layers. This study demonstrated, for the first time, infection with adults of C. hians trematode in the Black stork nesting in Slovakia. The presence of larvae and eggs in the tissues of the upper gastrointestinal tract of bird was associated with mild inflammatory response but feeding behaviour of adult worms in the ventriculus probably contributed to the enhanced susceptibility of the lamina propria mucosae to mechanical damage by inorganic material. Although larval stages have not yet been documented in the intermediate hosts in Slovakia, our report indicates that the life cycle of C. hians might occur in Central Europe.

Abstract

Serratospiculiasis is a parasitic disease caused by filariid nematodes of the genus Serratospiculum, the subfamily Dicheilonematinae. Serratospiculum spp. parasitizes the air sacs and members of this genus have been found in various species of Falcons, Bald Eagles and Cooper’s Hawk from all around the world. In the present study, infection with Serratospiculum was confirmed for the first time in the Great Tit in Slovakia. Nematode infestation was identified post mortem. Lesions in the respiratory system (airsacculitis, pneumonia) were associated with the presence of this nematode. Smears of the necrotic lesions in the crop and oesophagus contained the large numbers of embryonated eggs. Faecal samples were examined by flotation method and Serratospiculum eggs were found. Adult parasites were cleared in lactophenol solution and morphological analysis of male reproductive organs (shape of male nematode spicules) indicated the species Serratospiculum amaculata. Scattered inflammatory cells were seen in the mucosal and submucosal layers of infected oesophagus and inflammatory foci were found mainly in the stroma of the air sacs.

The presence of the filariid nematode in the nonspecific species Great Tit (Parus major) common in Slovakia indicates the importance of monitoring of serratospiculiasis in the avian hosts. The parasite can cause serious health problems, even sudden death of their hosts, therefore suitable effective measures for their elimination should be implemented.

Abstract

The effect of albendazole therapy on the reduction of drugsusceptible and drug-resistant strains of Haemonchus contortus larvae on day 10 post infection (p.i.), distribution and the relative numbers of innate immunity cells — eosinophils/neutrophils and mast cells in the stomach wall of immunosupressed Mongolian gerbils on days 4/1, 7/4, 10/7 and 14/11 post infection/post therapy (p.i./p.t.) were investigated in the present study. The efficacy of albendazole was significantly lower on benzimidazole (BZ) resistant larvae (L3 and L4 stages) (58.92 %) than the efficacy on susceptible strain of larvae (94.15 %). H. contortus infection elicited strong inflammation in mucosal and submucosal layers of the stomach, where mucosal mast cells MMC) were in the highest numbers in the lamina propria mucosae on day 7/4 p.i./p.t. Reduction of larval numbers following treatment resulted in a gradual decrease of MMC and connective tissue mast cells (CTMC). The lower counts of CTMC in the submucosa were seen in gerbils infected with BZ-susceptible strain during the whole period post therapy. In case of infection with BZ-resistant strain, peroxidase containig cells (eosinophils) peaked on day 7/4 p.i./p.t., whereas infection with BZ-susceptible strain elicited massive accumulation of these cells on day 4/1 p.i./p.t., particularly in the submucosa. No marked differences in eosinophils localisation were observed between both groups after the therapy. Goblet cells were found only in the proximal parts of glandulae gastricae close to the mucosal surface and no differences in the distribution in the stomach wall of both groups of animals were observed. After therapy the higher larval counts in case of BZ-resistant strain were in the correlation with the lower decline of CTMC and eosinophils, but MMC numbers were not significantly different between both treated groups. Present data indicate that in early stage post infection, the distribution of individual innate immunity cells might be directly affected by the larvae, and that the genetic and consequently biological differences related to the resistance to benzimidazoles probably had the impact on the interactions of larvae with the different immune cells in their niche.

Summary

Medicinal plants have been successfully used in the ethno medicine for a wide range of diseases since ancient times. The research on natural products has allowed the discovery of biologically relevant compounds inspired by plant secondary metabolites, what contributed to the development of many chemotherapeutic drugs. Flavonoids represent a group of therapeutically very effective plant secondary metabolites and selected molecules were shown to exert also antiparasitic activity. This work summarizes the recent knowledge generated within past three decades about potential parasitocidal activities of several flavonoids with different chemical structures, particularly on medically important flatworms such as Schistosoma spp., Fasciola spp., Echinococcus spp., Raillietina spp., and model cestode Mesocestoides vogae. Here we focus on curcumin, genistein, quercetin and silymarin complex of flavonolignans. All of them possess a whole spectrum of biological activities on eukaryotic cells which have multi-therapeutic effects in various diseases. In vitro they can induce profound alterations in the tegumental architecture and its functions as well as their activity can significantly modulate or damage worm´s metabolism directly by interaction with enzymes or signaling molecules in dose-dependent manner. Moreover, they seem to differentially regulate the RNA activity in numbers of worm´s genes. This review suggests that examined flavonoids and their derivates are promising molecules for antiparasitic drug research. Due to lack of toxicity, isoflavons could be used directly for therapy, or as adjuvant therapy for diseases caused by medically important cestodes and trematodes.

Abstract

We report the case of a 14-year-old girl who suffered from headache, fatigue, caught and a fever with body temperature up to 40 °C for a week. The patient had abdominal enlargement and clinical examination showed the hepatomegaly +5 cm. In ELISA assays employing Em2+ antigen, high titres of specific IgG antibodies to Echinococcus multilocularis somatic antigens were found in the serum. Western blot analysis also indicated on presence of alveolar echinococcosis (AE). CT examination showed expansive foci in the right liver lobe and histological examinations of the biopsy after PAS staining confirmed the presence of alveolar echinococcosis. After 320 days of chemotherapy with albendazole, CT revealed progression of parasitic foci and new abscess lesions inside parasitic cysts were detected, with some parts being necrotic. The surgical removing of foci was performed as following — the laparotomic revision, the removal of the right liver lobe with dilatation, reconstruction of v. cavae cum prothesis PTFE in length 12 cm. Three months after the operation, the rest of the patient’s left liver lobe had grownup and compensated at least a part of the removed liver.

Abstract

A study involved 1800 hospitalised children (age: 9 months to 16 years) examined by ovoscopic analyses and confirmed the occurrence of Ascaris lumbricoides and Trichuris trichiura in 46 patients (2.55 %). Of these, 30 patients had Ascaris infection, 13 were positive for both nematodes and 3 patients had Trichuris infection. The mean count of A. lumbricoides eggs in positive cases was 1050 eggs per gramme (EPG) in range 150–4450 EPG. The mean count of T. trichiura eggs was 150 EPG (50–250 EPG). The highest intensities of A. lumbricoides and T. trichiura infections occurred in children 3–5 years of age living in poor hygienic conditions. Most common clinical conditions in all the patients included anaemia combined with complicated bronchopneumonia, colitis and gastritis. The strongest correlation between the parasite burden and selected laboratory test data (eosinophil count, haemoglobin, total serum iron) was found in children of 2 years of age (P < 0.05) and decreased with age.