Role of stellate cells in hepatic echinococcosis in cattle.

Hydatid cysts formed by the metacestodes of Echinococcus granulosus. Cattle suffering from hydatid cyst shows fluid-filled structures, especially in liver. These parasite-induced cysts localized by forming fibrous capsules in the liver. Fibrogenesis is the host immune response in the liver against these parasites. Hepatic stellate cells (HSCs) are localized perisinusoidal space also known as vitamin A-storing cells, characterize the important fibrogenic cell type. In this study, livers from 15 animals with hydatid cyst and 8 healthy animals were used. Hematoxylin and Eosin, masson trichrome staining were performed on the prepared liver sections. Microscopically, cysts were bordered eosinophilic necrotic debris blended with degenerate neutrophils, macrophages, eosinophils, lymphocytes, plasma cells and multinucleated giant cells, which extend into the adjacent fibrous connective tissue. In Masson trichrome staining, the fibrous connective tissue was observed surrounding of hydatid cyst. Glial fibrillary acidic protein (GFAP), collagen I, GFAP/collagen I, positive cells were investigated using either indirect single- or double-labeling immunohistochemical staining. The results indicated that anti-GFAP-positive staining was seen in areas including fibrous tissue just under the foreign body giant cells surrounding the cyst wall. In double immunohistochemical staining, it was observed that HSCs labeled with anti-GFAP antibody in the fibrous connective tissue also labeled anti-collagen I antibody. This study shows that HSCs may responsible for synthesis the collagen I in the development of parasitic fibrosis in cystic echinococcosis in the liver of cattle.

Tracking acute phase protein response during acute and chronic Toxoplasma gondii infection.

Toxoplasmosis is a disease caused by the protozoan Toxoplasma gondii, which occurs worldwide in mammals and birds. Brain is the primary target organ because Toxoplasma gondii is a ubiquitous intracellular parasite that causes most frequently life-threatening encephalitis in immunocompromised patients. Relation of tissue cysts number, histopathology score and acute phase proteins were investigated. In this study, 36 mice are infected with Me49 strain of Toxoplasma gondii. The control group has 6 healthy mice. After inoculation of Toxoplasma gondii, at 10., 15., 20., 30., 45., 60. days, 6 each mice euthanized after collection of blood samples. Hemopexin, haptoglobulin, macroglobulin, serum amyloid A and clusterin levels are determined by ELISA. Then, brain tissues were investigated histopathologically and lesions were scored. The average cyst numbers were determined by counting three samples (25 µl each) of each brain homogenate under light microscopy. Inflammatory reaction was observed on day 10 days after inoculation (d.a.i.) The lesions were characterized by perivascular mononuclear cell infiltration, focal mononuclear cell infiltration in the meninges, and glial proliferation. Tissue cysts were observed in all Toxoplasma gondii-infected groups. The highest lesion score was observed at 60 d.a.i. And the most tissue cyst number were on day 30. d.a.i. Serum levels of hemopexin, haptoglobulin, macroglobulin, serum amyloid A and clusterin were significantly higher than the control group on day 10-20., 10., 10-30., 10.,10-45 d.a.i., respectively. High level of acute phase proteins in mice on certain days infected with Toxoplasma gondii was exhibited a relationship between brain lesions and tissue cysts.

Role of NETs in the difference in host susceptibility to Toxoplasma gondii between sheep and cattle.

The main aim of this study was to compare extracellular traps (NETs) formation by polymorphonuclear neutrophils (PMNs) of cattle and sheep when exposed to T. gondii tachyzoites in vitro. The effects of parasite concentrations and different incubation periods on NETs development in cattle and sheep PMNs were studied. The effect of NET structures on host cell invasion by tachyzoites was also studied. This is the first report of NETs development by sheep and cattle PMNs against T. gondii in vitro. T. gondii-induced extracellular DNA production from PMNs was dependent on tachyzoite concentrations and incubation time in both sheep and cattle. Many nuclear and cytoplasmic changes were observed in sheep and cattle PMNs after exposure to T. gondii tachyzoites. The typical appearance of NETs, with MPO, NE and histone (H3) attached to extracellular DNA, was observed. Tachyzoites were entrapped within this structure. Myeloperoxidase (MPO) activity was higher in the cattle PMN-tachyzoite co-cultures than sheep. NETs structures released from sheep PMNs caused mechanical immobilisation of T. gondii tachyzoites, however, NET structures released from cattle PMNs may be lethal to tachyzoites. Bovine MPO may have a lethal effect on T. gondii tachyzoites in vitro during a 3h incubation. Besides other mechanisms that effect on host susceptibility to T. gondii in sheep and cattle, extracellular traps formation as a part of immunological reactions may be play a role in host susceptibility to T. gondii.

Hepatic stellate cells increase in Toxoplasma gondii infection in mice.

BACKGROUND: Toxoplasma gondii is a ubiquitous protozoan parasite that can infect humans and animals. The severity of toxoplasmosis varies according to the immune status of the individual, parasite strain, and host species. In mammalian species, it has been observed that severe lesions of acute toxoplasmosis form in visceral organs such as the liver, lung, and spleen. Some epidemiological studies have reported an association of T. gondii infection with liver cirrhosis. METHODS: Acute infection was induced in fifteen 30-day-old normal Swiss albino mice. The mice were infected by intraperitoneal inoculation of 5000 T. gondii RH strain tachyzoites. The mice were sacrificed in groups of 5 at 2, 4, and 6 days after inoculation. Another group of 5 mice were used as the controls. Anti-glial fibrillary acidic protein (GFAP) and anti-T. gondii antibodies were used to compare GFAP-immunoreactive cells and anti-T. gondii-immunopositive areas in the liver between the T. gondii-infected groups and the healthy controls, respectively. RESULTS: There was a significant correlation between the numbers of GFAP-positive hepatic stellate cells (HSCs) when they were compared with T. gondii antigen immunostaining (p < 0.05). The amount of T. gondii immunostaining increased significantly with the increase in the number of HSCs. CONCLUSIONS: There is a significant relationship between the number of HSCs and T. gondii antigens, which may represent an active role of HSCs in liver pathology and the pathobiology of T. gondii-related hepatitis.

[Ticks and transmission of some important diseases by ticks]. / Keneler ve Kenelerin Tasidigi Bazi Onemli Hastaliklar.

Ticks which are commonly found all around the world are ectoparasites which are obliged to suck blood from vertebrates such as mammals and birds during all of their periods of develeopment. They may cause toxicities and paralyses in the course of blood sucking through saliva injection and the attachment sites may become ports of entry for secondary agents. Healthy animals that are severely infested by ticks can show a decreased yield and anemia. Young and sick animals can even die. Besides this, ticks are both biological and mechanical vectors for viruses, bacteria, rickettsias, spirochaetas, protozoons and helminths. Ten percent of the ticks identified in the world are associated with 200 diseases. In this review the taxonomy and morphology of ticks, some of the important diseases they carry and the diagnosis and treatment of these diseases are mentioned.

[Investigation of the prevalence of visceral leishmaniasis by the microculture method and IFAT in dogs in Kirikkale.]. / Kirikkale'deki Köpeklerde Mikrokültür Yöntemi ve IFAT ile Visseral Leishmaniosisin Prevalansinin Arastirilmasi.

This study was carried out in order to compare the seroprevalence of visceral leishmaniasis in dogs from different areas of Kirikkale between 2006-2008 using the microculture method (MCM) which is a new method, and the indirect fluorescent antigen test (IFAT). All of the blood collected from total of 50 dogs was found to be negative by MCM. Only one male Beagle strain dog (3 years old) was found to be seropositive at 1/128 titers (2%) for anti-Leishmania infantum IgG antibodies by IFAT.