NOTCH signaling inhibition after DAPT treatment exacerbates alveolar echinococcosis hepatic fibrosis by blocking M1 and enhancing M2 polarization.

Alveolar echinococcosis (AE) is a lethal helminthic liver disease caused by persistent infection with Echinococcus multilocularis (E. multilocularis). Although more and more attention has been paid to the macrophages in E. multilocularis infection, the mechanism of macrophage polarization, a critical player in liver immunity, is seldom studied. NOTCH signaling is involved in cell survival and macrophage-mediated inflammation, but the role of NOTCH signaling in AE has been equally elusive. In this study, liver tissue samples from AE patients were collected and an E. multilocularis infected mouse model with or without blocking NOTCH signaling was established to analyze the NOTCH signaling, fibrotic and inflammatory response of the liver after E. multilocularis infection. Changes in polarization and origin of hepatic macrophages were analyzed by flow cytometry. In vitro qRT-PCR and Western blot assays were performed to analyze key receptors and ligands in NOTCH signaling. Our data demonstrated that hepatic fibrosis develops after AE, and the overall blockade of NOTCH signaling caused by DAPT treatment exacerbates the levels of hepatic fibrosis and alters the polarization and origin of hepatic macrophages. Blocking NOTCH signaling in macrophages after E. multilocularis infection downregulates M1 and upregulates M2 expression. The downregulation of NTCH3 and DLL-3 in the NOTCH signaling pathway is significant. Therefore, NOTCH3/DLL3 may be the key pathway in NOTCH signaling regulating macrophage polarization affecting fibrosis caused by AE.

Correction: Histone demethylase LSD1 restricts influenza A virus infection by erasing IFITM3-K88 monomethylation.

[This corrects the article DOI: 10.1371/journal.ppat.1006773.].

Epidemiological Survey on Echinococcosis in Xinjiang Uygur Autonomous Region, People's Republic of China.

BACKGROUND: According to the latest data, the detection rate of echinococcus in Hoboksar Mongol Autonomous County was 3.7%. The objective of this study is to further investigate the epidemiology of echinococcosis in Ho-boksar Mongol Autonomous County of Xinjiang Uygur Autonomous Region, People's Republic of China and provide the scientific evidence for preventive and control measures. METHODS: We performed ultrasound examination of 521 people in Hoboksar Mongol Autonomous County of Xinjiang Autonomous Region, and collected 508 serum samples, which were analyzed with enzyme-linked immunosorbent assay. Data were analyzed by t-test and multinomial logistic regression for risk factor analysis. We collected 126 pieces of herder's dog feces and used double antibody sandwich method to detect the positive rate of fecal antigen. RESULTS: The prevalence rate of human echinococcosis in this region was 4.4% (23/521), including 4.0% (21/521) for cystic echinococcosis (CE), 0.38% (2/521) for alveolar echinococcosis (AE). It was found that CE seropositivity was significantly different from gender, age, ethnic group, occupation, culture, area, income and awareness of this disease. The seroprevalence rate of people aged 41 - 65 (3.74%) was higher than of age 0 - 17 (0.197%) (p > 0.05); Female serological positive (4.921%) was higher than male (1.772%) (p > 0.005); Mongolian serological positive (5%) was higher than Han (0.197%) and Kazakhs (1.181%) (p > 0.05); The herdsmen serological positive (2.756% was higher than students (0.197%) (p > 0.05); The primary school students serological positive (2.559%) was higher than children before school 0% (p > 0.05); Chagankule serological positive (9.211%) was higher than Bayinaow (8.497%) (p > 0.05); The seroprevalence rate of people with income < 2,000 (3.74%) was higher than people with income over 5,000 (0.197%) (p > 0.05); The seroprevalence rate of people who had no disease awareness (4.724%) was higher than those who had awareness of Hydatid disease (1.969%) (p < 0.05). Multivariate logistic regression show age, ethic group and awareness of station are the influence factors of epidemiology of echinococcosis. Canine fecal antigen positive rate was 50% (p > 0.05). Narenhebuke (48.78%) was higher than chahet (20.00%), but there is no statistical difference (p > 0.05). CONCLUSIONS: The surveillance data and our study results tend to be consistent that echinococcosis has an increasing trend in Hoboksar Mongol Autonomous County. Efforts should be continued, in both animals and humans by increasing training campaigns and public awareness.

The role of regulatory B cells in Echinococcus granulosus-infected mice.

To investigate the phenotypic changes of the expression level of regulatory B cells and related molecules during the continuous infection of Echinococcus granulosus (E. granulosus) in mice and its relationship with E. granulosus infection and its immune effect. Experimental group mice were inoculated with protoscoleces suspension via intraperitoneally injection to prepare a mouse model of E. granulosus infection. Flow cytometry was used to detect the expression of regulatory B cells CD1dhiCD5+CD19hi cells and CD1dhiCD5+CD19hi IL-10+ cells in spleen and peripheral blood of mice. The expressions of IL-10 and TGF-ß1 in mouse serum were detected via ELISA. The liver pathological changes in mice were observed by H&E staining; Moreover, the expressions and distribution of IL-10 and TGF-ß1 in mice liver were measured through immunohistochemistry. The ELISA test results showed no significant changes in serum IL-10 and TGF-ß1 levels in early infected mice. However, at the middle and late stages of infection, the levels of IL-10 and TGF-ß1 in the serum of mice increased significantly (P < 0.05). The proportion of CD1dhiCD5+CD19hiBreg cells and the proportion of CD1dhiCD5+CD19hiIL-10+Breg cells in the spleen of mice infected with E. granulosus were increased at 90 days after infection, which indicating that Breg cells proliferated in the late stage of infection. CD1dhiCD5+CD19hi regulatory B cells may be one of the causes of immunosuppression of E. granulosus infection. It is speculated that Bregs inhibitory effect may play a role by regulating the expression of cytokines and inducing the secretion of inhibitory cytokines IL-10 and TGF-ß1.

Correction: Histone demethylase LSD1 restricts influenza A virus infection by erasing IFITM3-K88 monomethylation.

[This corrects the article DOI: 10.1371/journal.ppat.1006773.].

Prolyl 4-hydroxylase 2 promotes B-cell lymphoma progression via hydroxylation of Carabin.

B-cell lymphomas are heterogeneous blood disorders with limited therapeutic options, largely because of their propensity to relapse and become refractory to treatments. Carabin, a key suppressor of B-cell receptor signaling and proliferation, is inactivated in B-cell lymphoma by unknown mechanisms. Here, we identify prolyl 4-hydroxylase 2 (P4HA2) as a specific proline hydroxylase of Carabin. Carabin hydroxylation leads to its proteasomal degradation, thereby activating the Ras/extracellular signal-regulated kinase pathway and increasing B-cell lymphoma proliferation. P4HA2 is undetectable in normal B cells but upregulated in the diffuse large B-cell lymphoma (DLBCL), driving Carabin inactivation and lymphoma proliferation. Our results indicate that P4HA2 is a potential prognosis marker for DLBCL and a promising pharmacological target for developing treatment of molecularly stratified B-cell lymphomas.

Histone demethylase LSD1 restricts influenza A virus infection by erasing IFITM3-K88 monomethylation.

The histone demethylase LSD1 has been known as a key transcriptional coactivator for DNA viruses such as herpes virus. Inhibition of LSD1 was found to block viral genome transcription and lytic replication of DNA viruses. However, RNA virus genomes do not rely on chromatin structure and histone association, and the role of demethylase activity of LSD1 in RNA virus infections is not anticipated. Here, we identify that, contrary to its role in enhancing DNA virus replication, LSD1 limits RNA virus replication by demethylating and activating IFITM3 which is a host restriction factor for many RNA viruses. We have found that LSD1 is recruited to demethylate IFITM3 at position K88 under IFNα treatment. However, infection by either Vesicular Stomatitis Virus (VSV) or Influenza A Virus (IAV) triggers methylation of IFITM3 by promoting its disassociation from LSD1. Accordingly, inhibition of the enzymatic activity of LSD1 by Trans-2-phenylcyclopropylamine hydrochloride (TCP) increases IFITM3 monomethylation which leads to more severe disease outcomes in IAV-infected mice. In summary, our findings highlight the opposite role of LSD1 in fighting RNA viruses comparing to DNA viruses infection. Our data suggest that the demethylation of IFITM3 by LSD1 is beneficial for the host to fight against RNA virus infection.

Human cytomegalovirus exploits interferon-induced transmembrane proteins to facilitate morphogenesis of the virion assembly compartment.

UNLABELLED: Recently, interferon-induced transmembrane proteins (IFITMs) have been identified to be key effector molecules in the host type I interferon defense system. The invasion of host cells by a large range of RNA viruses is inhibited by IFITMs during the entry step. However, the roles of IFITMs in DNA virus infections have not been studied in detail. In this study, we report that human cytomegalovirus (HCMV), a large human DNA virus, exploits IFITMs to facilitate the formation of the virion assembly compartment (vAC) during infection of human fibroblasts. We found that IFITMs were expressed constitutively in human embryonic lung fibroblasts (MRC5 cells). HCMV infection inhibited IFITM protein accumulation in the later stages of infection. Overexpression of an IFITM protein in MRC5 cells slightly enhanced HCMV production and knockdown of IFITMs by RNA interference reduced the virus titer by about 100-fold on day 8 postinfection, according to the findings of a virus yield assay at a low multiplicity of infection. Virus gene expression and DNA synthesis were not affected, but the typical round structure of the vAC was not formed after the suppression of IFITMs, thereby resulting in defective virion assembly and the production of less infectious virion particles. Interestingly, the replication of herpes simplex virus, a human herpesvirus that is closely related to HCMV, was not affected by the suppression of IFITMs in MRC5 cells. These results indicate that IFITMs are involved in a specific pathway required for HCMV replication. IMPORTANCE: HCMV is known to repurpose the interferon-stimulated genes (ISGs) viperin and tetherin to facilitate its replication. Our results expand the range of ISGs that can be exploited by HCMV for its replication. This is also the first report of a proviral function of IFITMs in DNA virus replication. In addition, whereas previous studies showed that IFITMs modulate virus entry, which is a very early stage in the virus life cycle, we identified a new function of IFITMs during the very late stage of virus replication, i.e., virion assembly. Virus entry and assembly both involve vesicle transport and membrane fusion; thus, a common biochemical activity of IFITMs is likely to be involved. Therefore, our findings may provide a new platform for dissecting the molecular mechanism of action of IFITMs during the blocking or enhancement of virus infection, which are under intense investigation in this field.

[Different Echinococcus granulosus antigens induced indoleamine 2,3-dioxygenase expression in dendritic cells].

OBJECTIVE: To observe the expression of indoleamine 2, 3-dioxygenase (IDO) in dendritic cells (DCs) via different Echinococcus granulosus antigens in vitro. METHODS: Bone Marrow DCs generated from bone marrow precursor cells of C57BL/6 mice and cultured in the presence of recombinant mouse GM-CSF (rmGM-CSF). Then, DCs were induced with 15 microg/ml recombinant antigen B (rAgB), 5 mg/ml mouse hydatid fluid (MHF), 1,000 U/ml IFN-gamma (as positive control), and RPMI 1640 complete medium (as negative control), respectively. Meanwhile, the treated DCs and cell supernatants were collected at 18, 24 and 48 h after induction. The positive expressions of D40, CD80, CD86 and I- A/I-E on DCs were determined by flow cytometry. By real-time fluorescent quantitative reverse-transcription polymerase chain reaction (FQ-RT-PCR), the expression level of IDO mRNA in DCs was measured. Concentrations of tryptophan (Try) were tested by high-performance liquid chromatography (HPLC) assay in cell supernatant. RESULTS: The data from flow cytometry showed that the positive expressions of CD40, CD80, CD86, I-A/I-E were decreased after stimulated by rAgB and MHF. At 24 h after induction, there was significant difference in the level of CD40, CD86 and I-A/I-E among rAgB-treated group [(22.60 +/- 2.69)%, (35.50 +/- 4.38)%, (57.30 +/- 4.38)%], MHF-treated group [(38.00 +/- 3.54)%, (53.00 +/- 3.39)%, (77.10 +/- 1.70)%] and negative control [(37.95 +/- 3.61)%, (19.55 +/- 1.06)% and (85.45 +/-1.63)%] (P < 0.05). At 18, 24 and 48 h after induction, the levels of IDO mRNA in rAgB-treated group [(9.20 +/- 0.01), (29.44 +/- 0.02), (16.48 +/- 0.04)] and MHF-treated group [(9.67 +/- 0.02), (17.52 +/- 0.01), (16.81 +/- 0.01)] was higher than that of negative control group [(2.46 +/- 0.01), (7.77 +/- 0.01), and (10.56 +/- 0.01)] (P < 0.01). And significant difference was found between rAgB-treated group and MHF-treated group (P < 0.05). At 18, 24 and 48 h after induction, the concentrations of Try were lowest in rAgB-treated group [(23.65 +/- 0.64), (13.95 +/- +1.06), (19.0 +/- 00.64) micro.mol/L]. At 24h after induction, Try concentration in negative control group (22.9 +/- 0.14) was higher than that of MHF-treated group (20.65 +/- 0.34) ( P < 0.05). CONCLUSION: Under in vitro condition, rAgB and MHF can up-regulate IDO expression. The ability of rAgB to up-regulate IDO activity was stronger than that of MHF at 24 h after induction.

Monocyte-derived macrophages: The supplements of hepatic macrophage in Echinococcus multilocularis infected mice.

BACKGROUND: Alveolar echinococcosis is a potentially lethal zoonosis caused by the cestode Echinococcus multilocularis. This study is to investigate the dynamic changes of monocytes, macrophages, and related cytokines in animal models of persistent infection of E. multilocularis. METHODS: An infection model was established by intraperitoneal injection of a protoscolex suspension. The pathological changes of liver were observed by HE staining. The percentage of Ly6Chi and Ly6Clo Monocytes in peripheral blood was detected by flow cytometry. The distribution and expression of CX3CL1, CX3CR1, iNOS, CD163, and CD11b in the liver were detected by immunohistochemistry. The mRNA expression of tumor necrosis factor-α (TNF-α) and Arg1 in the liver was detected by quantitative reverse transcription polymerase chain reaction. The expression of INF-γ, interleukin-17 (IL-17), IL-4, and IL-10 in peripheral blood was detected by enzyme-linked immunosorbent assay. RESULTS: Hematoxylin-eosin(HE) staining showed that significant lesions appeared in the later stages of infection in the liver. The proportion of Ly6Chi monocytes in the peripheral blood of the experimental group mice decreased after a brief rise, Ly6Clo monocytes decreased first and then increased. The expression of CX3CL1, CX3CR1, CD11b, CD163, and iNOS in the mice liver of the experimental group was increased. The expression level of TNF-α and Arg1 mRNA in the liver of the experimental group mice increased. The expression level of IFN-γ, IL-17, IL-4, and IL-10 increased with the duration of infection. CONCLUSIONS: Monocytes as a supplement to hepatic macrophage, monocytes and kupffer cells may both participate in Th1 and Th2 immune responses by differentiating into M1 or M2 at different stages of E. multilocularis infection.

[Clinical effect and safety of liposomal-albendazole and tablet-albendazole for the treatment of human cystic echinococcosis].

OBJECTIVE: To explore and compare the clinical effect and safety of liposomal albendazole (L-ABZ) and tablet-albendazole (T-ABZ) in the treatment of cystic echinococcosis (CE1, CE2, and CE3). METHODS: A total of 269 cases treated with cystic echinococcosis (CE) in Xinjiang Medical University the First Affiliated Hospital from 1998 to 2008 were reviewed. 51 cases were excluded and 218 cases were enrolled in this research by retrospective case-control method. Among 110 cases were treated with L-ABZ and 108 cases were treated with T-ABZ for short-term (3 months) and long-term courses (6 months) respectively. The effects and safety of the two medicines were compared by analyzing the clinical symptoms, imaging check and serologic test results. RESULTS: In short-term effect evaluation, the total effective rates and curative rates of L-ABZ group and T-ABZ group were 77.9% and 49.1% vs 28.4% and 13.9%, respectively. The effects of L-ABZ group was better than that of T-ABZ group, with remarkable difference in total effective rates and curative rates (x2 value was 19.581, 6.877, respectively, P is less than 0.05). In long-term effect evaluation, the total effective rates and curative rates of L-ABZ and T-ABZ group were 81.7% and 49.0% vs 47.6% and 20.6%, respectively. There was significant difference between L-ABZ group and T-ABZ group in total effective rates and curative rates (x2 value was 20.977, 15.049, respectively, P is less than 0.05). In T-ABZ group the short-term curative rates were 50.0% (15/30), 8.8% (8/91) and 33.3% (7/21) respectively in CE1, CE2, and CE3, the short-term total effective rates were 56.7% (17/30), 35.2% (32/91) and 61.9% (13/21) respectively in CE1, CE2, and CE3. The long-term curative rates were 58.3% (7/12), 28.6% (12/42) and 70.0% (7/10) respectively in CE1, CE2 and CE3, the long-term total effective rates were 75.0% (9/12), 69.0% (29/42) and 100.0% (10/10) respectively in CE1, CE2, and CE3. When compared with CE2, differences existed in CE1 (x2 = 24.887, 4.329; P is less than 0.05) and CE3 groups (x2 = 8.860, 5.076; P is less than 0.05) in terms of short-term effects. In L-ABZ group, the short-term curative rates were 47.4% (18/38), 12.2% (12/98) and 61.5% (8/13) respectively in CE1, CE2 and CE3, the short-term total effective rates were 92.1% (35/38), 65.3% (64/98) and 92.3% (12/13) respectively in CE1, CE2 and CE3, the long-term curative rates were 79.3% (23/29), 35.9% (23/64) and 50.0% (3/6) respectively in CE1, CE2 and CE3, the long-term total effective rates were 96.6% (28/29), 84.4% (54/64) and 100% (6/6) respectively in CE1, CE2 and CE3. When compared with CE2, there were significant differences in CE1 (x2 = 19.648, 9.930; P is less than 0.05) and CE3 groups (x2 = 18.880, 3.876; P is less than 0.05) in terms of short-term effect. In L-ABZ and T-ABZ groups, the drug-related adverse effects were 11.1% (12/108) and 12.7% (14/110) respectively without significant difference (x2 = 0.155, P is more than 0.05). CONCLUSION: L-ABZ and T-ABZ were both effective anti-echinococcosis drugs without dominant side-effects. The clinical effect of L-ABZ was better than that of T-ABZ.

[Echinococcus granulosus recombinant antigen B induced IDO expression in mouse bone marrow-derived dendritic cells in vitro].

OBJECTIVE: To observe the expression of indoleamine 2,3-dioxygenase (IDO) in mouse bone marrow-derived dendritic cells (DCs) after adding Echinococcus granulosus recombinant antigen B (rAgB) in vitro. METHODS: CD11c+ DCs generated from bone marrow precursor cells of C57BL/6 mice and cultured in the presence of recombinant mouse GM-CSF (rmGM-CSF). The morphology of DCs was observed by inverted microscope and scanning electronic microscope. The level of I-A/I-E, CD40, CD80, and CD86 on DCs were determined by flow cytometry. T cell proliferation induced by DCs were evaluated by using mixed lymphocyte reaction (MLR) assay. At day 6 post culture, the immature DCs were collected, and part of the immature DCs stimulated with lipopolysaccharide (LPS) for 24 h were examined by flow cytometry. Immature DCs were divided into 3 groups: negative control group, positive control group (rmIFN-gamma, 1000 U/ml) and rAgB group. Immature DCs of positive control group and rAgB group were induced with 1000 U/ml rmIFN-gamma and 15 microg/ml rAgB, respectively. IDO expression in DCs was examined 24 h after induction using immunohistochemical method and Western blotting. RESULTS: More than 80% CD11c+ DCs were harvested. The typical DCs were observed under inverted microscope and scanning electronic microscope. The level of CD40, CD80, and IA/IE (MHC II) in mature DCs group was significantly higher than that of immature DCs group (P < 0.05). In MLR, mitomycin-treated DCs can stimulate T lymphocytes proliferation activity. There were significantly differences in IDO expression in the negative control group [(4.544 +/- 1.752)%], positive control group [(20.464 +/- 4.452)%] and rAgB group [(11.148 +/- 1.966)%] (P < 0.05). Western blotting result indicated that the ratio of IDO/GAPDH in rAgB group (0.573 +/- 0.129) was significantly higher than that of negative group (0.229 +/- 0.085) (P < 0.05), and there were no significant difference in the ratio of IDO/GAPDH between IFN-gamma group (0.794 +/- 0.114) and rAgB group (P > 0.05). CONCLUSION: rAgB can induce IDO expression in bone marrow-derived dendritic cells in vitro.

Kupffer Cells: Important Participant of Hepatic Alveolar Echinococcosis.

Aims: Kupffer cells (KCs) are the liver-resident macrophages and play a leading role in the regulation of liver homeostasis in physiological conditions and in pathology. The study aims to investigate the anti-echinococcosis effect of KCs and the effects of hepatic stellate cells (HSCs) activation in the progression of liver fibrosis in hepatic alveolar echinococcosis (hepatic AE). Methods: Hematoxylin-eosin (H&E) and Masson staining were used to assess the pathological inflammatory changes and collagen deposition, respectively. Immunohistochemistry and qRT-PCR were used to detect the number of aggregates of KCs, the expression of cytokines and activation of HSCs. Results: In the close group, H&E staining showed that the normal lobular structure was destroyed and inflammatory infiltration around the lesion could be observed, and Masson staining showed that blue collagen fibers were clearly deposited near the portal area. IHC showed that KCs surface markers CD68 and CD163, cytokine iNOS and Arg-1 were positively expressed in the vicinity of inflammatory lesions. qRT-PCR indicated that TNF-α, IL-10, and TGF-ß1 secreted by KCs were significantly higher than those in the distance group (P < 0.01). It is worth noticing that the expression levels of anti-inflammatory cytokines were slightly higher than that of pro-inflammatory cytokines. Both IHC and qRT-PCR results showed that HSCs activation markers, the expression of α-SMA and Desmin significantly increased. Conclusions: Our research indicates that KCs have immune-protective effect of anti-echinococcosis and promote liver fiber repair, and it also suggests that they have potential therapeutic value for patients with hepatic AE.

H1N1 Virus Production and Infection.

Influenza A virus is a member of orthomyxoviridae family causing wide-spread infections in human respiratory tract. Mouse infection model is widely used in antiviral research and pathogenesis study against influenza A virus. Here, we report a protocol in infected mice with different virus doses and strains to explore how an inhibitor of lysine-specific demethylase (LSD1) impacts disease progression.