Hepatocyte mitochondrial DNA mediates macrophage immune response in liver injury induced by trichloroethylene.

We have previously shown that excessive activation of macrophage proinflammatory activity plays a key role in TCE-induced immune liver injury, but the mechanism of polarization is unclear. Recent studies have shown that TLR9 activation plays an important regulatory role in macrophage polarization. In the present study, we demonstrated that elevated levels of oxidative stress in hepatocytes mediate the release of mtDNA into the bloodstream, leading to the activation of TLR9 in macrophages to regulate macrophage polarization. In vivo experiments revealed that pretreatment with SS-31, a mitochondria-targeting antioxidant peptide, reduced the level of oxidative stress in hepatocytes, leading to a decrease in mtDNA release. Importantly, SS-31 pretreatment inhibited TLR9 activation in macrophages, suggesting that hepatocyte mtDNA may activate TLR9 in macrophages. Further studies revealed that pharmacological inhibition of TLR9 by ODN2088 partially blocked macrophage activation, suggesting that the level of macrophage activation is dependent on TLR9 activation. In vitro experiments involving the extraction of mtDNA from TCE-sensitized mice treated with RAW264.7 cells further confirmed that hepatocyte mtDNA can activate TLR9 in mouse peritoneal macrophages, leading to macrophage polarization. In summary, our study comprehensively confirmed that TLR9 activation in macrophages is dependent on mtDNA released by elevated levels of oxidative stress in hepatocytes and that TLR9 activation in macrophages plays a key role in regulating macrophage polarization. These findings reveal the mechanism of macrophage activation in TCE-induced immune liver injury and provide new perspectives and therapeutic targets for the treatment of OMDT-induced immune liver injury.

The role of Kupffer cell activation in immune liver damage induced by trichloroethylene associated with the IFN-γ/STAT1 signaling pathway.

Trichloroethylene (TCE) is a metal detergent commonly used in industry that can enter the human body through the respiratory tract and skin, causing occupational medicamentosa-like dermatitis due to TCE (OMDT) and multiple organ damage, including liver failure. However, the pathogenesis of liver injury remains unclear. Kupffer cells (KCs) are important tissue macrophages in the body because the polarization of KCs plays a crucial role in immune-mediated liver injury. However, the mechanism of KCs polarization in TCE-induced immune liver injury has not been thoroughly elucidated. In this study, we investigated the effect of TCE-induced KCs polarization on liver function and signal transduction pathways using the TCE sensitization model developed by our group. BALB/c mouse skin was exposed to TCE for sensitization, and an increase in the expression of M1 macrophage-specific markers (CD16/CD32, iNOS), M1 macrophage-specific cytokines IL-1ß, and IFN-γ, P-JAK-1 and P-STAT1 levels were also found to be dramatically increased. When using low doses of gadolinium trichloride (GdCl3), the expression of these proteins and mRNA was significantly reduced. This phenomenon indicates that GdCl3 blocks TCE-induced polarization of KCs and suggests that the IFN-γ/STAT1 signaling pathway may be involved in the polarization process of KCs. These findings clarify the relationship between the polarization of KCs and immune liver injury and highlight the importance of further study of immune-mediated liver injury in TCE-sensitized mice.

TNF-α/TNFR1 regulates the polarization of Kupffer cells to mediate trichloroethylene-induced liver injury.

We have previously shown trichloroethylene (TCE) induced immune liver injury, and TNF-α/TNFR1 pathway as a probably mechanism underlying the immune damage, but the pathogenic mechanism is still unclear. The study aims to investigate whether TNF-α and its receptors regulate Kupffer cell polarization and downstream inflammation signaling pathways during TCE sensitization, to clarify the mechanism of TCE-mediated immune liver injury. 6-8 weeks old SPF BALB/c female mice were used to establish a TCE sensitization model. We found that in the TCE sensitization positive group, liver injury was aggravated, Kupffer cells activated and polarized to M1 type. The expression of M1 Kupffer cell marker proteins CD11c and CD16/32 increased in the TCE positive group, so did TNF-α and TNFR1 in liver. The expression of P-IKK protein, PP65 protein and P-STAT3 protein increased in the TCE sensitization positive group, and the downstream inflammatory factors IL-1ß and IL-6 also increased in the TCE sensitization positive group. After using the TNFR1 inhibitor R7050, we found that M1 Kupffer cell polarization, TNF-α expression, signal pathway expression and inflammatory factors IL-1ß and IL-6 expression declined, and the liver damage relieved. Briefly, the use of R7050 to inhibit TNF-α/TNFR1 changing the polarization of liver M1 Kupffer cell, thereby inhibiting the activation of related downstream signaling pathways and reducing the secretion of inflammatory factors. TNF-α/TNFR1 regulates the polarization of M1 Kupffer cells inflammatory play an important role in liver immune damage.

Dietary Fat Intake and the Risk of Skin Cancer: A Systematic Review and Meta-Analysis of Observational Studies.

We conducted a meta-analysis to evaluate the association between fat intake and the risk of three major types of skin cancer including basal cell carcinoma (BCC), squamous cell carcinoma (SCC) and cutaneous malignant melanoma (CMM). A comprehensive search of PubMed and EMBASE was performed to identify all relevant observational studies published up to December 1, 2018. Specific odds ratio (OR) or relative risk (RR) estimates for the highest versus the lowest intake of dietary fat and 95% confidence intervals (CI) from the included studies were pooled using random effect model. Three prospective cohort studies (175,675 participants and 30,915 BCC cases, 4,106 SCC cases and 1,638 CMM cases) and nine case-control studies (328 BCC cases, 493 SCC cases, 1,547 CMM cases and 2,660 controls) were identified. The pooled results indicated that dietary consumption of total fat and saturated fat were not associated with three major types of skin cancer. High consumption of monounsaturated fat was significantly associated with a decreased risk of BCC (RR: 0.90, 95% CI: 0.85-0.96) and high level of polyunsaturated fat intake was potentially positively associated with SCC (RR: 1.19, 95% CI: 1.06-1.33). Our findings should be confirmed by further evidence from well-designed and large-scale prospective cohort studies.

Kupffer cell inactivation ameliorates immune liver injury via TNF-α/TNFR1 signal pathway in trichloroethylene sensitized mice.

METHODS: 36 female BALB/c mice were selected and randomly divided the mice into four groups. We established a BALB/c mouse model of TCE sensitization and pretreatment with GdCl3 (40 mg/kg) by intraperitoneal injection during the during the 17th and 19th days. RESULTS: We found F4/80, the marker of Kupffer cell, was increased in TCE positive group. GdCl3 treatment successfully blocked the activation of Kupffer cell. TNF-α was increased significantly in liver of TCE sensitized mice and decreased significantly when low-dose GdCl3 was used. We found TNF receptor 1 (TNFR1) was increased significantly and GdCl3 treatment resumed the expression of TNFR1 to normal level, as well as the F4/80, TNF-α and TNFR1 mRNA. We also found both caspase-8 and caspase-3 increased in TCE positive group and decreased in TCE + GdCl3 positive group. The number of apoptotic cells in TCE sensitized mice increased by TUNEL staining, and GdCl3 treatment alleviated this increase. Some cells showed edema and inflammatory cell aggregation in liver of TCE positive group, while in the TCE + GdCl3 positive group, the cytoplasm became loose and vacuole-like degeneration occurred. CONCLUSION: Our study unveils cross-talk between Kupffer cell activation and TNFR1 which mediate apoptosis in liver of TCE sensitized mice.

Complement regulatory protein CD59a plays a protective role in immune liver injury of trichloroethylene-sensitized BALB/c mice.

Trichloroethylene (TCE) is a major occupational and environmental chemical compound which causes occupational dermatitis medicamentosa-like of TCE with severe liver damage. Our previous studies showed that complement activation was a newly recognized mechanism for TCE-induced liver damage. The objective of this study was to explore the role of the key complement regulatory protein, CD59a, in TCE-induced immune liver injury. We firstly evaluated the changes of CD59a expression in liver tissue and then investigated if the changes were associated with membrane attack complex (MAC) formation, nuclear factor kappa B (NF-κB) activation and liver damage in BALB/c mice model of TCE-induced skin sensitization in the absence or presence of soluble recombinant rat CD59-Cys. The results showed that low expression of CD59a accompanied by MAC deposition in the liver of TCE-sensitized BALB/c mice, which was consistent in time. In addition, activation of NF-κB pathway, upregulation of inflammatory cytokine and liver damage also occured. Additional experiment showed that recombinant rat sCD59-Cys alleviated inflammation and liver damage in TCE-sensitized BALB/c mice. Moreover, recombinant rat sCD59-Cys reduced MAC formation and inhibited NF-κB activation measured by P-IκBα and nuclear NF-κB p65 in the liver of TCE-sensitized BALB/c mice. In conclusion, recombinant rat sCD59-Cys plays a protective role in immune liver injury of TCE-sensitized BALB/c mice.

Inflammatory kidney injury in trichloroethylene hypersensitivity syndrome mice: Possible role of C3a receptor in the accumulation of Th17 phenotype.

Trichloroethylene (TCE) is a common organic solvent which can cause TCE hypersensitivity syndrome (THS) in exposure workers. THS is an adverse skin disorder with severe inflammatory kidney damage. Complement C3a receptor (C3aR) acts as a specific receptor for the key complement cleavage product C3a and involves multiple inflammatory responses, but the role of C3aR in TCE induced kidney inflammatory injury remains unknown. In this study, BALB/c mouse model of skin sensitization induced by TCE was set up in the presence or absence of C3aR antagonist (C3aRA). Kidney pathology and renal function, expression of inflammatory mediators and C3aR, changes in Th17 cell numbers, and activation of signal transducer and activator of transcription 3 (STAT3) in the kidney were examined. TCE sensitization produced histopathological and functional damage to the kidney, accompanied by increased levels of interleukin (IL-) 1ß, IL-6, and IL-23. Local accumulation of Th17 cells and enhanced phosphorylation of STAT3 were also seen in the impaired kidney in TCE sensitization-positive mice. C3aR was mainly located in the impaired glomerulus and upregulated in TCE sensitization-positive mice. C3aRA pretreatment alleviated the structural and functional kidney damage and the inflammatory cytokine and Th17 responses by TCE sensitization, and specifically reduced the phosphorylation of STAT3. Together, our results demonstrate that C3aR signaling promotes the inflammatory responses and regulates the accumulation of Th17 phenotype via phosphorylation of STAT3 in TCE sensitization induced inflammatory kidney damage. C3aR may serve as a potential therapeutic target in TCE sensitization mediated kidney injury.

Role of selective blocking of bradykinin B1 receptor in attenuating immune liver injury in trichloroethylene-sensitized mice.

Trichloroethylene (TCE) is able to induce trichloroethylene hypersensitivity syndrome (THS) with multi-system immune injuries. In our previous study, we found kallikrein-kinin system (KKS) activation, including the bradykinin B1 receptor (B1R), which contributed to immune organ injury in TCE sensitized mice. However, the mechanism of B1R mediating immune dysfunction is not clarified. The present study initiates to investigate the potential mechanism of B1R on liver injury. We establish a TCE sensitized BALB/c mouse model to explore the mechanism with or without a B1R inhibitor R715. We found B1R expression was increased in TCE sensitization-positive mice. As expect, hepatocyte intracellular organelles and mitochondria disappeared, glycogen particles reduced significantly as well in TCE sensitization-positive mice via the transmission electron microscopic examination, meanwhile, R715 alleviated the deteriorate above. The blockade of B1R resulted in a significant decreased p-ERK1/2 and increased p-AKT expression. The expression of CD68 kupffer cell and its relative cytokine, including IL-6 and TNF-α, increased in TCE sensitization-positive mice and decreased in R715 pretreatment TCE sensitization-positive mice. Together, the results demonstrate B1R plays a key role in ERK/MAPK and PI3K/AKT signal pathway activation and inflammation cytokine expression in immune liver injury induced by TCE. B1R exerts a pivotal role in the development of TCE induced liver injury.

Viral mimic polyinosine-polycytidylic acid potentiates liver injury in trichloroethylene-sensitized mice - Viral-chemical interaction as a novel mechanism.

Occupational trichloroethylene (TCE) exposure can induce hypersensitivity dermatitis and severe liver injury. Recently, several clinical investigations indicate that viral infection, such as human herpesvirus-6, is associated with hepatic dysfunction in patients with TCE-related generalized skin disorders. However, whether viral infection potentiates TCE-induced liver injury remains unknown. This study aimed to explore the contribution of viral infection to the development of TCE-sensitization-induced liver injury in BALB/c mice. Female BALB/c mice were randomly assigned into four groups: solvent control group (n = 20), TCE group (n = 80), poly(I:C) group (n = 20) and combination of TCE and poly(I:C) (poly(I:C)+TCE) group (n = 80). Poly(I:C) (50 µg) was i.p. administrated. TCE and poly(I:C)+TCE groups were further divided into sensitization and non-sensitization subgroup. Complement 3 and C3a protein levels, and complement factors were measured. Combination treatment significantly enhanced TCE-induced liver injury, decreased complement 3, but increased C3a in serum and liver tissues in sensitization group. These changes were not correlated with the hepatic complement 3 transcription. Moreover, combination treatment specifically promoted complement factor B, but not factor D and factor H expressions. These data provide first evidence that poly(I:C) potentiates liver injury in BALB/c mouse model of TCE-sensitization. Upregulated C3a and factor B contributes to the poly(I:C) action in TCE-induced liver injury. This new mode of action may explain increased risk of chemical-sensitization induced tissue damage by viral infection.

Trichloroethylene Alters Th1/Th2/Th17/Treg Paradigm in Mice: A Novel Mechanism for Chemically Induced Autoimmunity.

The role of environmental factors in autoimmune diseases has been increasingly recognized. While major advance has been made in understanding biological pathogen-induced autoimmune diseases, chemically triggered autoimmunity is poorly understood. Trichloroethylene (TCE), a common environmental pollutant, has recently been shown to induce autoimmunity. This study explored whether TCE could cause imbalance of T helper (Th) cell subsets which would contribute to the pathogenesis of TCE-induced medicamentosa-like dermatitis. BALB/c mice were treated with TCE via drinking water at doses of 2.5 or 5.0 mg/mL for 2, 4, 8, 12, and 16 weeks. Trichloroethylene exposure caused time- and dose-dependent increase in Th1, Th2, and Th17 and decrease in regulatory cell (Treg) in the spleen at 2, 4, 8, 12, and 16 weeks, with greatest changes mainly at 4 weeks. These effects were mirrored by similar changes in the expression of their corresponding cytokines interferon-γ, interleukin 4 (IL-4), IL-17A, and IL-10. Mechanistically, these phenotypic changes were accounted for by alterations to their respective master transcription factors T-box expressed in T cells, GATA-binding protein 3, Retinoic acid-related orphan receptor ct (RORct), and forkhead box P3. Of interest, TCE treatment shifted the ratios of Th1/Th2 and Th17/Treg; specifically, TCE increased Th17/Treg. These findings provide the first evidence that TCE exposure significantly changes the Th1/Th2/Th17/Treg paradigm and their specific cytokines driven by altered master transcription factors. This may promote autoimmune reactions in the pathogenesis of TCE-induced skin sensitization and associated damage to other tissues.

The immune response in trichloroethylene hypersensitivity syndrome: A review.

Trichloroethylene (TCE) has been used for a variety of industrial and consumer cleaning purposes because of its ability to dissolve organic substances. The multisystem injuries include those of skin, liver, and kidney, which are defined as TCE hypersensitivity syndrome (THS). THS is a serious occupational health issue. However, the mechanism of immune dysfunction leading to organ injury is poorly understood. Many studies reveal that skin lesions and organ injury caused by TCE are consistent with type IV hypersensitivity, also called delayed hypersensitivity, mediated by T cells. However, many researchers found T cell-mediated type IV hypersensitivity could not account for the pathogenesis of THS fully. Humoral immunity, including immunoglobulins and complement activation, may also play a possible role in THS pathogenesis. This review will describe the history, current understanding, and future research directions of the mechanism of THS.

Complement C5a-C5aR interaction enhances MAPK signaling pathway activities to mediate renal injury in trichloroethylene sensitized BALB/c mice.

We have previously shown complement activation as a possible mechanism for trichloroethylene (TCE) sensitization, leading to multi-organ damage including the kidneys. In particular, excessive deposition of C5 and C5b-9-the membrane attack complex, which can generate significant tissue damage, was observed in the kidney tissue after TCE sensitization. The present study tested the hypothesis that anaphylatoxin C5a binding to its receptor C5aR mediates renal injury in TCE-sensitized BALB/c mice. BALB/c mice were sensitized through skin challenge with TCE, with or without pretreatment by the C5aR antagonist W54011. Kidney histopathology and the renal functional test were performed to assess renal injury, and immunohistochemistry and fluorescent labeling were carried out to assess C5a and C5aR expressions. TCE sensitization up-regulated C5a and C5aR expressions in kidney tissue, generated inflammatory infiltration, renal tubule damage, glomerular hypercellularity and impaired renal function. Antagonist pretreatment blocked C5a binding to C5aR and attenuated TCE-induced tissue damage and renal dysfunction. TCE sensitization also caused the deposition of major pro-inflammatory cytokines IL-2, TNF-α and IFN-γ in the kidney tissue (P < 0.05); this was accompanied by increased expression of P-p38, P-ERK and P-JNK proteins (P < 0.05). Pretreatment with the C5aR antagonist attenuated the increase of expression of P-p38, P-ERK and P-JNK proteins (P < 0.05) and also consistently reduced the TCE sensitization-induced increase of IL-2, TNF-α and IFN-γ (P < 0.05). These data identify C5a binding to C5aR, MAP kinase activation, and inflammatory cytokine release as a novel mechanism for complement-mediated renal injury by sensitization with TCE or other environmental chemicals.

The association of mannose-binding lectin genetic polymorphisms with the risk of rheumatoid arthritis: a meta-analysis.

OBJECTIVE: To better understand the risks of rheumatoid arthritis (RA) and certain subsets conferred by mannose-binding lectin (MBL2) polymorphisms in different races. MATERIALS AND METHODS: Eighteen articles (4810 cases and 4585 controls) were identified from the latest literature search carried out in May 2014 using PubMed, Web of Science, Wanfang Database (Chinese) and Chinese National Knowledge Infrastructure. Three single nucleotide polymorphisms of codon 52, 54 and 57, exonic and extended genotypic variance in MBL2 were synthesized. RESULTS: Codon 54 mutation of MBL2 was unlikely to be a risk factor for RA in overall population, but turned out to be deleterious in East Asian (four studies with 523 cases and 647 controls, pooled OR:1.63, 95% CI: 1.23-2.17). Codon 54 mutation increased the risk of seropositive and erosive RA by 44% and 162%, respectively (three studies with 281 cases and 358 controls, 95% CI: 1.01-2.05; 3 studies with 180 cases and 499 controls, 95% CI: 1.77-3.88). Furthermore, those risks were relatively stronger when restricted in East Asian (two studies with 147 cases and 244 controls, pooled OR: 1.85, 95% CI: 1.19-2.87; 2 studies with 170 cases and 291 controls, pooled OR: 2.78, 95% CI: 1.85-4.20). No remarkable associations were detected regarding codon 52, 57, exon 1 and extended genotype of MBL2. CONCLUSIONS: Polymorphism of codon 54 in MBL2 may predispose to RA, especially seropositive or erosive RA, which East Asian appears to be more vulnerable.

Association of a disintegrin and metalloprotease 33 (ADAM33) gene polymorphisms with the risk of COPD: an updated meta-analysis of 2,644 cases and 4,804 controls.

A series of observational studies have been made to investigate the association of the ADAM33 gene polymorphisms with the risk of COPD, but their results were conflicting. Therefore, we performed an updated meta-analysis to quantitatively summarize the associations of ADAM33 gene polymorphisms with the risk of COPD. Thirteen case-control studies referring to nine SNPs were identified: V4 (rs2787094), T+1 (rs2280089), T2 (rs2280090), T1 (rs2280091), S2 (rs528557), S1 (rs3918396), Q-1 (rs612709), F+1 (rs511898) and ST+5 (rs597980). A dominant model (AA+Aa vs. aa), recessive model (AA vs. Aa+aa), additive model (AA vs. aa) and allelic model (A vs. a) were used to evaluate the association of ADAM33 polymorphism with the risk of COPD. The results indicated that significant associations were found for ADAM33 T1, T2, S1, Q-1, F+1 and ST+5 polymorphisms associated with the risk of COPD in different populations. However, no significant associations were found for V4, T+1 and S2 polymorphisms with the risk of COPD in all genetic models, even in the subgroup analysis by ethnicity. This meta-analysis provided evidence that the ADAM33 T1, T2, S1, Q-1, F+1 and ST+5 six locus polymorphisms association with the risk of COPD. Furthermore, T2, Q-1 and ST+5 indicated an association with the risk of COPD in the European populations, whereas T1, T2, S1, F+1 and Q-1 indicated an association with the risk of COPD in the Asian populations.

An Animal Model of Trichloroethylene-Induced Skin Sensitization in BALB/c Mice.

Trichloroethylene (TCE) is a major occupational hazard and environmental contaminant that can cause multisystem disorders in the form of occupational medicamentosa-like dermatitis. Development of dermatitis involves several proinflammatory cytokines, but their role in TCE-mediated dermatitis has not been examined in a well-defined experimental model. In addition, few animal models of TCE sensitization are available, and the current guinea pig model has apparent limitations. This study aimed to establish a model of TCE-induced skin sensitization in BALB/c mice and to examine the role of several key inflammatory cytokines on TCE sensitization. The sensitization rate of dorsal painted group was 38.3%. Skin edema and erythema occurred in TCE-sensitized groups, as seen in 2,4-dinitrochlorobenzene (DNCB) positive control. Trichloroethylene sensitization-positive (dermatitis [+]) group exhibited increased thickness of epidermis, inflammatory cell infiltration, swelling, and necrosis in dermis and around hair follicle, but ear painted group did not show these histological changes. The concentrations of serum proinflammatory cytokines including tumor necrosis factor (TNF)-α, interferon (IFN)-γ, and interleukin (IL)-2 were significantly increased in 24, 48, and 72 hours dermatitis [+] groups treated with TCE and peaked at 72 hours. Deposition of TNF-α, IFN-γ, and IL-2 into the skin tissue was also revealed by immunohistochemistry. We have established a new animal model of skin sensitization induced by repeated TCE stimulations, and we provide the first evidence that key proinflammatory cytokines including TNF-α, IFN-γ, and IL-2 play an important role in the process of TCE sensitization.

Bleomycin-induced epithelial-mesenchymal transition in sclerotic skin of mice: possible role of oxidative stress in the pathogenesis.

Epithelial-mesenchymal transition (EMT) derived myofibroblasts are partly responsible for the increased collagen synthesis and deposition that occur in tissue fibrosis; however EMT occurrence in skin fibrosis and its mechanism remain unknown. The aim of this study was to investigate whether epithelial cells undergo EMT and determine the role of oxidative stress in this process. BALB/c mice were subcutaneously injected with bleomycin (BLM) or phosphate buffer saline (PBS) into the shaved back daily for 2, 3, and 4weeks. Skin collagen deposition was evaluated by histopathology and Western blotting. EMT characteristics in the skin were determined by histopathology and immunofluorescent staining for E-cadherin and vimentin, which were further evaluated by Western blotting and reverse transcriptase polymerase chain reaction (RT-PCR). To investigate the role of oxidative stress in EMT, the antioxidant N-acetylcysteine (NAC) was intraperitoneally (100mg/kg body weight/day) injected daily for 3weeks. The epithelial suprabasal cells were detached from the basement membrane zone (BMZ) in the sclerotic skin treated with BLM. Immunofluorescent staining indicated vimentin-positive epithelial cells frequently occurring in the thickened epidermis of BLM-treated mice. Western blotting and RT-PCR showed that the expression of E-cadherin was significantly decreased but that of vimentin significantly increased in the skin treated with BLM. NAC attenuated BLM induced oxidative damage, changes in E-cadherin and vimentin expressions and collagen deposition in the sclerotic skin of mice. This study provides the first evidence that BLM induces the EMT of the epithelial cells superficial to the basement membrane zone in the skin fibrosis. Oxidative stress may contribute, at least in part, to BLM induced EMT and skin fibrosis in mice.

[Effect of trichloroethylene intake via drinking water on Th17 cells in BALB/c mice].

OBJECTIVE: This study aimed to investigate the effect of trichloroethylene (TCE) intake via drinking water on Th17 cells in mice. METHODS: Forty eight six weeks old female BALB/c mice were divided into blank control, vehicle control, 2.5 mg/ml TCE and 5.0 mg/ml TCE groups by random number table (12 mice each group), and exposed to TCE by drinking water. On the 14(th), 28(th), 56(th), 84(th) days, blood were collected and assayed for IL-17, IL-6, and TGF-ß concentration in serum through ELISA. Animals were killed and spleen biopsies were taken sterility. The proportion of Th17 cells among CD4(+) T cells and RORγt mRNA expression level in spleen were measured by FCM and real-time PCR. RESULTS: In 2.5 mg/ml TCE and 5.0 mg/ml TCE group mice, Th17 cells/CD4(+) T cells in spleen were (3.46 ± 0.32)% and (5.45 ± 0.45)% on day 14, (3.47 ± 0.33)% and (4.10 ± 0.39)% on day 84, which were significantly higher than those for solvent control group at the same time point ((2.15 ± 0.20)%, (2.16 ± 0.35)%, respectively) (P < 0.01). RORγt mRNA expression levels were (1.870 ± 0.084) and (1.965 ± 0.060) on 14 day, (1.998 ± 0.079) and (2.028 ± 0.073) on day 56, which were also significantly higher than those for solvent control group at the same time point (1.77 ± 0.04 and 1.75 ± 0.09, respectively) (P < 0.05). IL-17 concentrations in serum were (32.28 ± 5.38) and (34.47 ± 5.02) pg/ml on day 14, and (34.87 ± 5.48) and (41.94 ± 6.19) pg/ml on day 28, which were significantly higher than those for solvent control group at the same time point((21.57 ± 5.23), (22.11 ± 5.11) pg/ml). IL-6 concentration in serum were (43.07 ± 6.71) and (47.86 ± 8.52) pg/ml on day14, (41.32 ± 7.04) and (46.74 ± 9.33) pg/ml on day 56, which were significantly higher than solvent control group at the same time point ((7.56 ± 7.71) and (28.26 ± 7.22) pg/ml). TGF-ß concentration were (17.48 ± 3.06) and (18.93 ± 3.12) pg/ml on day 14, which did not show significant difference from solvent control group ((15.25 ± 2.95) pg/ml). Correlation analysis showed that IL-6 in serum were significantly positively correlated with the proportion of Th17 cells among CD4(+) T cells and RORγt expression level in spleen (r = 0.741, 0.765, P < 0.01). CONCLUSION: TCE might promote the differentiation of Th17 cells and increase IL-17 secretion by inducing IL-6 and up-regulating RORγt expression together with TGF-ß.

[Changes in humoral immunity in sensitized guinea pigs exposed to trichloroethylene].

OBJECTIVE: To study the changes of serum complement C and immunoglobulin (Ig) in sensitized guinea pigs exposed to trichloroethylene. METHODS: Thirty six white female guinea pigs (250 ∼ 300 g) were randomly divided into blank control group (5 guinea pig), solvent (olive oil) control group (5 guinea pig) and TCE treatment group (26 guinea pig). According to guinea pig maximization test (GPMT), guinea pigs were exposed to TCE. After stimulating contact for 24 h, the skin reactions of guinea pig back test area were recorded and scored. According to Skin sensitization integral, the guinea pigs treated with TCE were divided into the sensitized group (score ≥ 1) and un-sensitized group (score 0). The concentrations of serum C3, C4, IgA, IgG and IgM were detected in 24 and 72 h, respectively after the experiment. RESULTS: The sensitization rates of group treated by TCE was 65.38%. The serum C3 levels of groups sensitized to TCE for 24 and 73h were 99.75 ± 1.45 and 93.28 ± 3.61g/ml, respectively, which were significantly lower than that (112.30 ± 9.10 g/ml) of solvent control group (P < 0.05). Also The serum C4 levels of groups sensitized to TCE for 24 and 73 h were 34.63 ± 2.53 and 33.82 ± 2.76g/ml, respectively, which were significantly lower than that (43.87 ± 3.65 g/ml) of solvent control group (P < 0.05). The serum IgA and IgM levels of groups sensitized to TCE and unsensitized to TCE for 24 and 72 h were significantly lower than those of solvent group (P < 0.05). as compared with unsensitized groups, the serum IgA levels of the groups sensitized to TCE for 24 and 72 h significantly decreased (P < 0.05). CONCLUSION: After the guinea pig skin was sensitized to TCE, the serum C3, C4 levels decreased, the immune function disordered.

Identification of Key Genes for Hepatitis Delta Virus-Related Hepatocellular Carcinoma by Bioinformatics Analysis.

BACKGROUND: It has been proposed that hepatitis delta virus (HDV) induces hepatic carcinogenesis by distinct molecular events compared with hepatocellular carcinoma (HCC) that is commonly induced by other hepatitis viruses. This study aimed to explore the underlying mechanism by identifying the key genes for HDV-HCC using bioinformatics analysis. METHODS: The GSE107170 dataset was downloaded and the differentially expressed genes (DEGs) were obtained by the online tool GEO2R. Gene otology (GO) functional analyses and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed using R packages. The protein-protein interaction (PPI) network was constructed by Search Tool for the Retrieval of Interacting Genes/Proteins (STRING). Hub genes were selected by Cytoscape software according to degree algorithm. The hub genes were further validated in terms of expression and survival analysis based on public databases. RESULTS: A total of 93 commonly upregulated genes and 36 commonly downregulated genes were found. The top 5 upregulated hub genes were TFRC, ACTR2, ARPC1A, ARPC3, and ARPC2. The top 5 downregulated hub genes were CTNNB1, CCND1, CDKN1B, CDK4, and CDKN1A. In the validation analysis, the expressions of ARPC1A, ARPC3, and CDK4 were promoted in general liver cancer samples. Higher expressions of ARPC2 and CDK4 and lower expressions of CDKN1A, CCND1, and CDKN1B were associated with worse prognosis in general HCC patients. CONCLUSION: The present study identifies a series of key genes that may be involved in the carcinogenesis of HDV-HCC and used as prognostic factors.