Role of stellate cells in hepatic echinococcosis in cattle

Biased Quantification of Rat Liver Fibrosis-Meta-Analysis with Practical Recommendations and Clinical Implications

For liver fibrosis assessment, the liver biopsy is usually stained with Masson's trichrome (MT) or picrosirius red (PSR) to quantify liver connective tissue (LCT) for fibrosis scoring. However, several concerns of such semiquantitative assessments have been raised, and when searching for data on the amount of LCT in healthy rats, the results vastly differ. Regarding the ongoing reproducibility crisis in science, it is necessary to inspect the results and methods, and to design an unbiased and reproducible method of LCT assessment. We searched the Medline database using search terms related to liver fibrosis, LCT and collagen, rat strains, and staining methods. Our search identified 74 eligible rat groups in 57 studies. We found up to 170-fold differences in the amount of LCT among healthy Wistar and Sprague-Dawley rats, with significant differences even within individual studies. Biased sampling and quantification probably caused the observed differences. In addition, we also found incorrect handling of liver fibrosis scoring. Assessment of LCT using stereological sampling methods (such as systematic uniform sampling) would provide us with unbiased data. Such data could eventually be used not only for the objective assessment of liver fibrosis but also for validation of noninvasive methods of the assessment of early stages of liver fibrosis.

Evaluation of the Local Immune Response to Hydatid Cysts in Sheep Liver

In order to characterize the inflammatory phenotype of livers of sheep naturally infected by cystic echinococcosis, 100 sheep livers have been macroscopically assessed for the presence of hydatid cysts and sampled for histopathological and molecular analysis. According to gross and microscopic examination, livers were subsequently classified into three groups: normal liver (Group A), liver with the presence of fertile hydatid cysts (Group B), and liver with the presence of sterile hydatid cysts (Group C). Immunohistochemical analyses were accomplished using primary antibodies anti-Iba1, anti-CD3, anti-CD20, anti-TGF-β, and anti-MMP9. Finally, real-time PCR was performed in order to estimate the concentration levels of tumor necrosis factor-α (TNF-α), interferon-γ (INF-γ), interleukin (IL)-12, IL-10, and TGF-β. Immunohistochemical analysis showed a diffuse immunolabelling of mononuclear cells for Iba-1 and TGF-β and a higher amount of CD20+ B cells compared to CD3+ T cells in both Groups B and C. The expression levels of Th-1-like immune cytokines TNF-α, INF-γ, and IL-12 did not show significant statistical differences. However, we found a significant increase in expression levels of Th-2 immune cytokines TGF-β and IL-10 in Groups B and C compared to Group A. Taken together, our findings suggest that macrophages have a predominant role in the local immune response to cystic echinococcosis. Moreover, we can speculate that Th2 immunity may be dominant, corroborating the idea that B cells are decisively essential in the control of the immune response during parasitic infection and that the immunomodulatory role of IL-10 and TGF-β may ensure the persistence of the parasite within the host.

Liver fibrosis is a common pathological change in the liver of dairy cows with fatty liver

Fatty liver (i.e., hepatic lipidosis) is a prevalent metabolic disorder in dairy cows during the transition period, characterized by excess hepatic accumulation of triglyceride (TG), tissue dysfunction, and cell death. Detailed pathological changes, particularly hepatic fibrosis, during fatty liver remain to be determined. Liver fibrosis occurs as a consequence of liver damage, resulting from the excessive accumulation of extracellular matrix, which distorts the architecture of the normal liver, compromising its normal synthetic and metabolic functions. Thus, we aimed to investigate liver fibrosis status and its potential causal factors including oxidative stress, hepatocyte apoptosis, and production of inflammatory cytokines in the liver of cows with fatty liver. Forty-five dairy cows (parity, 3-5) were selected, and liver biopsy and blood were collected on the second week postpartum (days in milk, 10-14 d). On the basis of the degree of lipid accumulation in liver, selected cows were categorized into normal (n = 25; TG <1% wet wt), mild fatty liver (n = 15; 1% ≤ TG <5% wet wt), and moderate fatty liver (n = 5; 5% ≤ TG <10% wet wt). Compared with normal cows, blood concentrations of nonesterified fatty acids and β-hydroxybutyrate, along with alanine aminotransferase and aspartate aminotransferase activities, were greater in the cows with fatty liver (mild and moderate). Hepatic extracellular matrix deposition, as indicated by Picrosirius red staining, was greater in cows with fatty liver than those with normal ones. In addition, we observed an increased proportion of collagen type I fiber in extracellular matrix with increased lipid accumulation in the liver. Compared with normal cows, the area of α-smooth muscle actin (α-SMA)-positive staining along with the mRNA abundance of collagen type I α 1 (COL1A1), ACTA2 (gene encoding α-SMA), and transforming growth factor-β (TGFB) were greater in cows with fatty liver. Compared with normal cows, hepatic contents of malondialdehyde, glutathione disulfide, and 8-isoprostane were greater, whereas total antioxidant capacity, the hepatic content of glutathione, and activities of antioxidant indicators, including superoxide dismutase, glutathione peroxidase, and catalase, were lower in cows with fatty liver. The number of terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling-positive cells and abundance of apoptosis-related molecules BAX, CASP3, CASP8, and CASP9 were greater in cows with fatty liver. However, mRNA abundance of the anti-apoptotic gene BCL2 did not differ. The mRNA abundance of pro-inflammatory cytokines including tumor necrosis factor-α (TNFA), interleukin-1β (IL1B), and interleukin-6 (IL6) was greater in the liver of cows with fatty liver. Overall, the present study indicated that fibrosis is a common pathological response to liver damage and is associated with oxidative stress, hepatocyte death, and inflammation.

Calcifying nanoparticles initiate the calcification process of mesenchymal stem cells in vitro through the activation of the TGF-β1/Smad signaling pathway and promote the decay of echinococcosis

The role of the calcifying nanoparticles (CNPs) in the calcification process of the outer cyst wall in hepatic cystic echinococcosis (HCE) remains unknown. CNPs were isolated from the tissues of the patients with HCE. Western blotting, alkaline phosphatase staining, and alizarin staining were performed to detect the cellular calcium ion deposition induced by the CNPs. CCK-8 and flow cytometry assays were conducted to determine the effect of CNPs on the apoptosis of mesenchymal stem cells (MSCs). Western blot experiments were performed to examine the expression levels of apoptosis-related factors and TGF-β1/Smad signaling pathway constituents. Treatment with CNPs induced the differentiation of MSCs. Calcium-related proteins, including OPN, BMP-2, and RUNX2, were upregulated after the CNP treatment. Similarly, CNP exposure increased the cellular calcium ion deposition in MSCs. In addition, the expression of Bax and Caspase-8 was elevated by the CNPs in MSCs. Treatment with CNPs promoted MSC apoptosis and inhibited the MSC growth. The TGF-β1/Smad signaling pathway was also activated after the CNP treatment. This study indicated that CNPs may play a critical role in initiating calcification of the outer cyst wall of HCE and promote the decay of echinococcosis, providing a new strategy for the treatment of hepatic echinococcosis.

Autoimmunity in human CE: Correlative with the fertility status of the CE cyst

Cystic echinococcosis is speculated to exert several immune-evasion strategies involving autoimmune-phenomena. We evaluated the hypothesizes that the prevalence of autoantibodies increases in the sera of CE patients that may evidence the association between the parasite and autoimmune diseases. Sera from 63 subjects at distinct types of CE cyst fertility were investigated for antinuclear antibodies (ANA), and anti-CCP antibodies. Plasma levels and cellular production of IL-17A cytokine were specifically defined as being assumed to prime for autoimmunity. Healthy-controls were age and gender-matched to test sera. ANA expressions inside the surgically removed metacestode and adventitial layer were also assayed. Out of 63 patients, 35 % had fertile highly viable cysts (group-1), 41 % had fertile low viable cysts (group-2) and 24 % had non-fertile cysts (group-3). A four-fold increase in ANA sera-levels was detected in group-1 compared with their controls (p-value 0.001) while anti-CCP levels were of insignificant differences. In group-2 and group-3, no significant differences were detected between ANA and anti-CCP sera-levels in CE patients and their controls. IL-17A sera-levels in group-1 and group- 2 were significantly higher than their healthy-controls while being of insignificant differences in group-3, p-value= 0.300. No association was detected between sera-levels of IL-17A and ANA as well as anti-CCP antibodies. Interestingly, relative IL-17A cellular expression associated positive ANA deposition in the parasite cells and adventitial layer. Collectively, based on the parasite fertility, IL-17A and ANA seemed to be involved in the host immune defenses against CE. There is no association between CE and anti-CCP antibodies.

Determination of macrophage types by immunohistochemical methods in the local immune response to liver hydatid cysts in sheep

Cystic echinococcosis is a zoonotic parasitic disease caused by Echinococcus granulosus. The main hosts in the life cycle of this parasite are dogs and other carnivores; The intermediate hosts are human, sheep, goat, cattle, pig, buffalo, horse and camel. The parasite damages the tissue by forming lesions in the form of fluid-filled cysts in the liver. These lesions are bounded by a layer of local inflammatory cells formed by the host. In the layer formed by this inflammatory response, there are lymphocytes, neutrophils and eosinophil leukocytes, including macrophages. Samples taken from sheep with hydatid cysts in their livers were followed for pathological analysis, and then histopathological and immunohistochemical examinations were performed. After histopathological examinations, the types of macrophages involved in the local immune response against cysts in the liver were determined by immunohistochemical methods using anti-INOS and anti-IL-10 antibodies. INOS and IL-10 immunopositivity were detected in all samples. Statistically, no significant difference was observed between these immunopositivity. This showed that both macrophage types are involved in the local immune response to hydatid cyst, and that Th1 and Th2 immune response stimulation continues together. It was concluded that in future studies that will be planned and experimentally, it will be possible to reveal more clearly how these macrophage types take part in the local immune response.

Hepatic inflammation and liver fibrogenesis: A potential target for the treatment of cystic echinococcosis-associated hepatic injury

To investigate the effect of cystic echinococcosis (CE) on liver damage, we developed a secondary experimental echinococcosis in Swiss mice by intraperitoneal inoculation of viable protoscoleces. Mice were randomly allocated into three groups: Ctrl group, PBS group, and CE group. Mice were euthanized and associated indications were investigated to evaluate inflammatory and fibrotic responses in liver. Hepatic damage and fibrotic reaction were histologically analyzed. The hepatic expression of iNOS, TNF-α, NF-κβ, vimentin, Bcl-2 and CD68 was evaluated by Immunohistochemical examinations. Interestingly, a significant iNOS, TNF-α, NF-κβ, vimentin, Bcl-2 and CD68 increase levels was observed in liver tissue and pericystic layer of hepatic hydatid cyst and correlate with the abundance of collagen and reticulin fibers. These observations could promote a potential target for the treatment of CE-associated hepatic injury.

Histological and immunological insights to hydatid disease in camels

PURPOSE

To investigate the immuno-histological evidences in viable and non-viable hydatid cysts obtained from naturally infected camels.

METHODS

A cohort study (February 2018-December 2019), a total of 15 hydatidosis-infected camels from slaughter houses in Cairo were involved. Specimens were investigated for parasite viability, liver histological changes, IL-17A cytokine immunohistochemical expressions in the adventitial layer, and the anti-nuclear antibodies (ANAs) immunofluorescent expression in the metacestode's structures. Real-Time Quantitative -Morphocytometry and SPSS were utilized.

RESULTS

Multi-focal lesions and high viability were found in 60% of the cases. Overall accumulation of collagen associated the parasite establishment that involved infiltrations of mononuclear cells with significantly increased IL-17A expression. Interestingly, the ANAs appeared to have a role in the immune-defense against the metacestode showing different patterns. ANAs production correlated with IL-17A expression and the viability of the parasite.

CONCLUSION

IL-17A responses in hydatidosis is associated with collagen deposition and ANA production as a sort of anti-parasite immunity in a viability dependent manner.

A combination of pirfenidone and TGF-β inhibition mitigates cystic echinococcosis-associated hepatic injury

Cystic echinococcosis (CE) occurs in the intermediate host's liver, assuming a bladder-like structure surrounded by the host-derived collagen capsule mainly derived from activated hepatic stellate cells (HSCs). However, the effect of CE on liver natural killer (NK) cells and the potential of transforming growth factor-β (TGF-β) signalling inhibition on alleviating CE-related liver damage remain to be explored. Here, by using the CE-mouse model, we revealed that the inhibitory receptors on the surface of liver NK cells were up-regulated, whereas the activating receptors were down-regulated over time. TGF-β1 secretion was elevated in liver tissues and mainly derived from macrophages. A combination of TGF-β signalling inhibitors SB525334 and pirfenidone could reduce the expression of TGF-β1 signalling pathway-related proteins and collagen production. Based on the secretion of TGF-β1, only the pirfenidone group showed a depressing effect. Also, the combination of SB525334 and pirfenidone exhibited a higher potential in effectively alleviating the senescence of the hepatocytes and restoring liver function. Together, TGF-β1 may be a potential target for the treatment of CE-associated liver fibrosis.