Immune-mediated hepatitis: Basic concepts and treatment.

Immunotherapy with immune checkpoint inhibitors (ICIs) has revolutionized advanced cancer management. Nevertheless, the generalized use of these medications has led to an increase in the incidence of adverse immune-mediated events and the liver is one of the most frequently affected organs. Liver involvement associated with the administration of immunotherapy is known as immune-mediated hepatitis (IMH), whose incidence and clinical characteristics have been described by different authors. It often presents as mild elevations of amino transferase levels, seen in routine blood tests, that spontaneously return to normal, but it can also manifest as severe transaminitis, possibly leading to the permanent discontinuation of treatment. The aim of the following review was to describe the most up-to-date concepts regarding the epidemiology, diagnosis, risk factors, and progression of IMH, as well as its incidence in different types of common cancers, including hepatocellular carcinoma. Treatment recommendations according to the most current guidelines are also provided.

Comparison of hematopoietic stem cell transplantation and immunosuppressive therapy as the first-line treatment option for patients with severe hepatitis-associated aplastic anemia.

Hepatitis-associated aplastic anemia (HAAA) is a rare variant of acquired aplastic anemia characterized with a syndrome of bone marrow failure after hepatitis. We retrospectively analyzed the outcomes of consecutive severe HAAA patients who received immunosuppressive therapy (IST, n = 70), matched-sibling donor hematopoietic stem cell transplantation (MSD-HSCT, n = 26) or haploidentical-donor (HID) HSCT (n = 11) as the first-line treatment. In the IST group, the hematologic response (HR) rate was 55.71% at 6 months. In contrast, HSCT recipients exhibited significantly more rapid and sustained hematopoiesis (HR 76.92%, 96.15% and 96.15% at 3, 6 and 12months, respectively). The 5-year overall survival (OS) was not different among IST (83.7 ± 4.9%), MSD-HSCT (93.3 ± 6.4%) and HID-HSCT group (80.8 ± 12.3%). Compared with IST, MSD and HID-HSCT demonstrated a trend of superiority in the estimated 5-year failure-free survival rates (93.3 ± 6.4% vs 64.3 ± 6.0%, p = 0.05; 80.8 ± 12.3% vs 64.3 ± 6.0%, p = 0.57). In subsequent stratified analysis on age, we found that HID-HSCT showed its efficacy and safety among young patients. In sum, MSD-HSCT remains first-line treatment choice for HAAA, whereas HID-HSCT represents an alternative treatment choice in addition to IST for young patients (< 40 years) without a matched sibling donor.

Diagnosis, treatment, and prevention of severe acute hepatitis of unknown etiology in children.

BACKGROUND: Severe acute hepatitis of unknown etiology in children has recently exhibited a global trend of concentrated occurrence. This review aimed to summarize the current available information regarding the outbreak of severe acute hepatitis and introduce our hospital's previous experiences with the diagnosis and treatment of severe acute hepatitis for reference. DATA SOURCES: Websites including the UK Health Security Agency, European Centre for Disease Prevention and Control, CDC, WHO, and databases including PubMed/Medline, Cochrane Library, Embase and Web of Science were searched for articles on severe acute hepatitis in children. RESULTS: As of May 26, 2022, a total of 650 cases have been reported in 33 countries; at least 38 (6%) children required liver transplantation, and nine (1%) died. Cases are predominantly aged between 3 and 5 years old, and there are no epidemiological links among them. The common manifestations are jaundice, vomiting and pale stools. Adenovirus tested positive in most cases, and SARS-CoV-2 and other viruses were detected in a few cases, but virus particles were not found in liver tissue. Adenovirus immunohistochemistry showed immunoreactivity in the intrasinusoidal lumen from some liver samples. The hierarchical treatment includes symptomatic and supportive therapy, management of coagulation disorders and hepatic encephalopathy, artificial liver support, and liver transplantation (approximately 6%-10% of cases require liver transplant). CONCLUSIONS: The etiology of this severe acute hepatitis in children is not clear. The clinical features are severe acute hepatitis with significantly elevated liver enzymes. Clinicians need to be alert to children with hepatitis.

Comparable clinical outcomes of haploidentical hematopoietic stem cell transplantation in patients with hepatitis-associated aplastic anemia and non-hepatitis-associated aplastic anemia.

Hepatitis-associated aplastic anemia (HAAA), a rare subtype of aplastic anemia (AA), is defined as bone marrow failure occurring after acute hepatitis. Severe HAAA requires immunosuppressive therapy (IST) or hematopoietic stem cell transplantation (HSCT) as lifesaving treatment. The outcomes of HAAA patients who underwent haploidentical hematopoietic stem cell transplantation (haplo-HSCT) have not been systematically evaluated. We retrospectively compared the characteristics of 15 patients with HAAA and 60 non-hepatitis-associated aplastic anemia (non-HAAA) patients, all 75 of whom underwent haplo-HSCT in our hospital between January 2006 and October 2021. The median ages of the patients were 18 years old (range, 3-36) for HAAA patients and 13 years (range, 2-45) for non-HAAA patients (p = 0.693). The median time for neutrophil engraftment was 14 days (range, 11-22) in the HAAA group and 12 days (range, 10-21) in the non-HAAA group (p = 0.363). At the time of analysis, 15 HAAA patients and 58 non-HAAA patients were alive, and their median follow-up times were 37 (range, 3-87) months and 31 (range, 2-110) months (p = 0.347), respectively. There were no significant differences in the three-year overall survival (OS) rates (100% vs. 96.7 ± 0.33%, P = 0.638) or liver event-free survival (LEFS) (80.0 ± 0.17% vs. 76.7 ± 0.19%, P = 0.747) between the two groups. Despite the small number of HAAA patients due to the rarity of the disease, these results, such as the similar incidence rates of 3-year OS and fewer liver events than expected, suggest that haplo-HSCT is a feasible treatment for HAAA a when there are no human leukocyte antigen (HLA)-matched donors available and has a low risk of transplant-related mortality and complications.

Hepatitis-Associated Aplastic Anemia: Etiology, Clinical Characteristics and Outcome.

Hepatitis-associated aplastic anemia (HAA) is a form of acquired aplastic anemia (AA) in which bone marrow failure develops after an acute attack of hepatitis. Bone marrow failure leading to AA is generally severe in cases of HAA and fatal if left untreated. This retrospective multicenter study investigated clinical and laboratory characteristics, possible causes, treatment, and outcome of HAA in children. Twenty patients from 8 centers were included in the study. Aspartate aminotransferase and alanine aminotransferase were <3 to 5×upper limit of normal (ULN) in 2 patients, <5 to 10×ULN in 2 patients, and >10×ULN in 16 patients. Acute liver failure developed in 5 (29%) patients. Pancytopenia was simultaneously present in 6 of 20 (30%) patients. Eleven of the 20 patients (55%) were alive, in remission and transfusion free. Those who were alive either had undergone hematopoietic stem cell transplantation and/or immunosuppressive treatment, except 1 patient who had received no treatment. Patients with the diagnosis of acute hepatitis should be evaluated and followed up carefully for presence of cytopenia, so that definitive treatment of AA can be initiated in a timely and appropriate manner when needed.

Hepatitis-Associated Aplastic Anemia.

Hepatitis-associated aplastic anemia (HAAA) is a rare illness, characterized by onset of pancytopenia with a hypoplastic bone marrow that traditionally occurs within 6 months of an increase in serum aminotransferases. HAAA is observed in 1% to 5% of all newly diagnosed cases of acquired aplastic anemia. Several hepatitis viruses have been linked to the disease, but in many cases no specific virus is detected. The exact pathophysiology is unknown; however, immune destruction of hematopoietic stem cells is believed to be the underlying mechanism. HAAA is a potentially lethal disease if left untreated. Management includes immunosuppression with antithymocyte globulin and cyclosporine and allogeneic hematopoietic stem cell transplantation.

Early therapeutic plasma exchange may improve treatment outcomes in severe acute toxic Hepatitis.

BACKGROUND AND OBJECTIVES: Acute toxic hepatitis can result in a different clinical course from a completely curable disease to subacute hepatitis, chronic hepatitis, and fulminant hepatitis failure, which is quite mortal. For this purpose, therapeutic plasma exchange (TPE) can be used for improving treatment outcomes by reducing the harmful substances caused with and/or without liver function in acute toxic hepatitis. We aimed to evaluate treatment outcomes in severe acute toxic hepatitis patients who applied early TPE procedure. MATERIALS AND METHODS: A total of 335 patients who received TPE between 2010-2021 were retrospectively screened and 59 (male/female, 30/29; min/max-age, 22-84) patients with acute toxic hepatitis who underwent TPE in the first 24 h were included in the study. TPE was performed in patients who had high total bilirubin level (>10 mg/dL). Laboratory parameters of the patients before and after the TPE procedure, number of patients developed complications of acute toxic hepatitis and mortality rates were evaluated for effectiveness of TPE. RESULTS: Acute toxic hepatitis was associated with hepatotoxic drugs in 44 (74.5 %), herbal medication 6 (10.2 %), mushroom poisoning 6 (10.2 %) and with substance abuse 3 (5.1 %) in patients. When the patients were compared based on INR, liver function tests, ammonia, lactate and Model For End-Stage Liver Disease (MELD) score at baseline, 48 h after TPE (independently of TPE number) and before final state a statistically significant decrease was observed in all parameters (p < 0.05). Fifty three (90 %) of patients improved without complications, the remaining 6 (10 %) patients were diagnosed with fulminant hepatitis. All these remaining patients died before liver transplantation (LTx) could be performed. CONCLUSION: TPE is a safe, tolerable therapy option and early TPE may improve treatment outcomes in severe acute toxic hepatitis.

Nucleic acid delivery for therapeutic applications.

Recent medical advances have exploited the ability to address a given disease at the underlying level of transcription and translation. These treatment paradigms utilize nucleic acids - including short interfering RNA (siRNA), microRNA (miRNA), antisense oligonucleotides (ASO), and messenger RNA (mRNA) - to achieve a desired outcome ranging from gene knockdown to induced expression of a selected target protein. Towards this end, numerous strategies for encapsulation or stabilization of various nucleic acid structures have been developed in order to achieve intracellular delivery. In this review, we discuss several therapeutic applications of nucleic acids directed towards specific diseases and tissues of interest, in particular highlighting recent technologies which have reached late-stage clinical trials and received FDA approval.

Live Combined B. subtilis and E. faecium Alleviate Liver Inflammation, Improve Intestinal Barrier Function, and Modulate Gut Microbiota in Mice with Non-Alcoholic Fatty Liver Disease.

BACKGROUND Non-alcoholic fatty liver disease (NAFLD) is a chronic, progressive liver disease with an increasing incidence rate. This study investigated the protective effects of live combined Bacillus subtilis and Enterococcus faecium (LCBE) on NAFLD, and its possible mechanisms. MATERIAL AND METHODS Five-week-old C57BL/6 mice were randomly divided into 3 groups: chow, HFD, and HFD+LCBE groups. The levels of serum biochemical markers, glucose tolerance, insulin, the inflammatory cytokines IL-1ß, IL-6, and TNF-alpha, LPS, and histological staining were measured using commercial kits. qPCR was used to examine the mRNA expression levels of inflammatory cytokines in the liver. Western blotting was used to determine the protein levels of TLR4, NF-kappaB p65, PPAR-alpha, and CPT-1 in the liver, and occludin and Claudin1 in the intestine. The intestinal flora of the mice was analyzed by high-throughput sequencing of the V3-V4 region of 16S rDNA. RESULTS LCBE significantly lowered the body weight, liver/body weight ratio, and serum glucose level, and increased the serum insulin level in NAFLD mice. In addition, LCBE treatment improved the liver function and lipid profile, decreased the levels of LPS and inflammatory cytokines, and downregulated the expression of TLR4 and NF-kappaB p65. Moreover, LCBE enhanced the intestinal barrier function by increasing the expression of occludin and Claudin1. Furthermore, LCBE modulated the composition of the gut microbiota by reducing the Firmicutes to Bacteroidetes ratio, and the proportion of inflammation-related and LPS-producing bacteria, thus re-arranging the structure of the gut microbiota. CONCLUSIONS LCBE protects against NAFLD by alleviating inflammation, restoring the intestinal barrier, and modulating gut microbiota composition.

Mitotherapy: Unraveling a Promising Treatment for Disorders of the Central Nervous System and Other Systemic Conditions.

Mitochondria are key players of aerobic respiration and the production of adenosine triphosphate and constitute the energetic core of eukaryotic cells. Furthermore, cells rely upon mitochondria homeostasis, the disruption of which is reported in pathological processes such as liver hepatotoxicity, cancer, muscular dystrophy, chronic inflammation, as well as in neurological conditions including Alzheimer's disease, schizophrenia, depression, ischemia and glaucoma. In addition to the well-known spontaneous cell-to-cell transfer of mitochondria, a therapeutic potential of the transplant of isolated, metabolically active mitochondria has been demonstrated in several in vitro and in vivo experimental models of disease. This review explores the striking outcomes achieved by mitotherapy thus far, and the most relevant underlying data regarding isolated mitochondria transplantation, including mechanisms of mitochondria intake, the balance between administration and therapy effectiveness, the relevance of mitochondrial source and purity and the mechanisms by which mitotherapy is gaining ground as a promising therapeutic approach.

Hepatic Manifestations of Nonhepatotropic Infectious Agents Including Severe Acute Respiratory Syndrome Coronavirus-2, Adenovirus, Herpes Simplex Virus, and Coxiella burnetii.

Nonhepatotropic viruses such as adenovirus, herpes simplex virus, flaviviruses, filoviruses, and human herpes virus, and bacteria such as Coxiella burnetii, can cause liver injury mimicking acute hepatitis. Most of these organisms cause a self-limited infection. However, in immunocompromised patients, they can cause severe hepatitis or in some cases fulminant hepatic failure requiring an urgent liver transplant. Hepatic dysfunction is also commonly seen in patients with severe acute respiratory syndrome coronavirus-2 infection. Patients with preexisting liver diseases are likely at risk for severe coronavirus disease 2019 (COVID-19) and may be associated with poor outcomes.

Successful Treatment of a 19-Month-Old Boy with Hepatitis Associated Aplastic Anemia by Infusion of Umbilical Cord-Derived Mesenchymal Stromal Cells: A Case Report.

Here we presented a case of a 19-month-old boy who developed severe aplastic anemia postacute hepatitis. He was treated successfully with the umbilical cord-derived mesenchymal stromal cells (UC-MSCs) infusion and cyclosporine A (CsA). The boy achieved both hematopoietic recovery and normal lymphocyte proportion. So far, his condition still remains stable. To our knowledge, there is a rare previous report on the utility of MSCs infusion for the treatment of hepatitis-associated aplastic anemia (HAAA). Considering the efficacy, safety, and strong operability, particularly for pediatric patient, the infusion of UC-MSCs combined with CsA could be an effective alternative for the treatment of HAAA.

Efficiency of Double Plasma Molecular Absorption System on the Acute Severe Cholestatic Hepatitis.

BACKGROUND: Cholestasis may lead to hepatic cirrhosis and a longer hospital stay. A part of the patients with cholestasis requires liver transplantation. However, most of the treatment efficiency of cholestatic hepatitis (CH) is not satisfactory. For the patients with severe CH after artificial liver support, there was a lack of systemic evaluation on the treatment efficiency of double plasma molecular absorption system (DPMAS) for acute severe CH. OBJECTIVE: We aim to investigate the treatment efficiency of DPMAS on acute severe CH. METHODS: This retrospective study involved 309 cases diagnosed with acute severe CH admitted to the First Affiliated Hospital, Zhejiang University. We compared the prognosis of patients received standard medical therapy (SMT) and SMT + DPMAS. Besides, the effects of DPMAS on total bilirubin (TBIL) and prothrombin time (PT) were investigated. RESULTS: DPMAS could significantly reduce the requirements for liver transplantation in the CH patients. After DPMAS therapy, significant decline was noticed in the TBIL, direct bilirubin (DBIL), total bile acid, and cholesterol. The baseline ratio of neutrophil showed significant elevation in the patients received 4 or more DPMAS compared with those received less DPMAS. CONCLUSIONS: DPMAS could significantly eliminate the necessity of liver transplantation. The artificial liver support system should be conducted to bring down the bilirubin level and the ratio of cases with severe conditions. In general, DPMAS should be preferred as an artificial liver support therapy for the patients with acute severe CH.

Toxicities from immunotherapy: From clinical trials to real-world clinical practice / Toxicidades de la inmunoterapia: de los ensayos clínicos a la práctica clínica en el mundo real

In recent years, immunotherapy has become an important pillar of cancer treatment, with high response rates regardless of tumour histology or baseline mutations. However, immune activation associated with check-point inhibitors is not selective and a large variety of immune-related adverse events have been associated with anti-PD1, anti-PD-1/L-1 and anti-CTLA-4 agents. Though diagnosis and treatment of these toxicities have been established according to the recommendations from clinical trials and in line with the autoimmune disorders that they mimic, increasing real-world data is coming up showing that these adverse events may have differential characteristics and management, especially in terms of the use of corticoids, second-line treatments, salvage therapy for life-threatening cases and reintroduction of immunotherapy. Herein we present a comprehensive review of current recommendations and real-world data on the main immune-related adverse events of immunotherapy

En los últimos años la inmunoterapia se ha convertido en un pilar fundamental para el tratamiento del cáncer, con altas tasas de respuesta, independientemente de la histología tumoral o de las mutaciones basales. Sin embargo, la activación inmune asociada a los inhibidores de control no es selectiva, habiéndose asociado una gran variedad de efectos adversos relacionados con la inmunidad a los agentes anti-PD1, anti-PD-1/L-1 y anti-CTLA-4. Aunque se han establecido el diagnóstico y el tratamiento de estas toxicidades en virtud de las recomendaciones de los ensayos clínicos, en consonancia con los trastornos autoinmunes que imitan, el incremento de los datos del mundo real refleja que dichos efectos adversos pueden tener características y manejos diferenciales, especialmente en términos de uso de corticoides, tratamientos de segunda línea, terapia de rescate para casos potencialmente letales, y reintroducción de la inmunoterapia. Presentamos aquí una revisión amplia de las recomendaciones actuales y los datos del mundo real sobre los principales efectos adversos de la inmunoterapia

The miR-21 potential of serving as a biomarker for liver diseases in clinical practice.

The role of miR-21 in the pathogenesis of various liver diseases, together with the possibility of detecting microRNA in the circulation, makes miR-21 a potential biomarker for noninvasive detection. In this review, we summarize the potential utility of extracellular miR-21 in the clinical management of hepatic disease patients and compared it with the current clinical practice. MiR-21 shows screening and prognostic value for liver cancer. In liver cirrhosis, miR-21 may serve as a biomarker for the differentiating diagnosis and prognosis. MiR-21 is also a potential biomarker for the severity of hepatitis. We elucidate the disease condition under which miR-21 testing can reach the expected performance. Though miR-21 is a key regulator of liver diseases, microRNAs coordinate with each other in the complex regulatory network. As a result, the performance of miR-21 is better when combined with other microRNAs or classical biomarkers under certain clinical circumstances.

Diseases and access to treatment by the Peruvian prison population: an analysis according to gender.

OBJECTIVE: In Peru, prisons are spaces with overcrowding, deteriorated infrastructure, poor sanitary conditions and difficult access to medical treatment. The objective of this study is to estimate the burden of disease and access to treatment for different morbidities in the Peruvian inmate population. METHODS: An analysis of secondary data of the First National Penitentiary Census (PCNP) 2016 in Peru was carried out. The absolute frequencies and percentages of each self-reported health condition, the presence of a diagnosis of a disease before entering the prison system and access to treatment were obtained. RESULTS: 74,130 inmates were included in the analysis. The most common diseases in prisons are depression (9.6%), anxiety (8.6%), chronic lung disease (8.4%) and arterial hypertension (6.9%). All diseases included, with the exception of hepatitis, have a diagnostic before the incarceration of less than 60%. Access to medical treatment was higher in women than in men and in general, mental health illnesses had low access to medical treatment. CONCLUSIONS: Chronic and infectious diseases are frequent in those deprived of liberty, with mental health problems being more prevalent in women. In general, access to treatment is low, especially in men and for mental health illnesses. This situation reflects the need to develop intervention programs that promote health and increase the universality of health care in those deprived of liberty.

Characterization of IL-21-expressing recombinant hepatitis B virus (HBV) as a therapeutic agent targeting persisting HBV infection.

Chronic infection by hepatitis B virus (HBV) is associated with high risks of liver fibrosis, cirrhosis and hepatocellular carcinoma. In mouse models of HBV persistence, interleukin 21 (IL-21) has been identified as a potent inducer of viral clearance. Strict hepatotropism makes recombinant HBV (rHBV) vectors ideal for liver-targeting gene delivery. Previously, we established an rHBV vector termed 5c3c, which is highly replicative by itself, but requires HBV envelope proteins provided in trans to produce virions. 5c3c-based rHBV virions are capable of delivering cargo gene expression driven by HBV Sp1 promoter into infected hepatocytes. In this work, we explore the feasibility of using 5c3c-derived rHBV for liver-specific delivery of IL-21 as treatment of chronic HBV infection. Methods: 5c3c-derived rHBV replicons harboring mouse or human IL-21 genes (termed 5c3c-mIL-21 and 5c3c-hIL-21 respectively) were constructed and then tested for the production of rHBV virions in vitro and in vivo. 5c3c-mIL-21's anti-HBV effects were determined in chronic HBV mouse model. Furthermore, superinfection by rHBV virions was analysed using HBV-infected HepG2/NTCP cells and human liver chimeric mice. Results: 5c3c-mIL-21 and 5c3c-hIL-21 were efficiently replicative and produced enveloped virions when provided with envelope proteins, both in vitro and in vivo. In mouse model of HBV persistence, IL-21 expressed from injected 5c3c-mIL-21 replicon induced complete viral clearance. 5c3c-mIL-21 and 5c3c-hIL-21 virions could infect HepG2/NTCP cells and engender sustained IL-21 expression. Most importantly, IL-21-expressing rHBV virions could superinfect HBV-infected HepG2/NTCP cells and human hepatocytes in human liver chimeric mice, and engender sustained IL-21 expression and rHBV production. Conclusion: These data suggest the high potential of 5c3c-derived IL-21-expressing rHBV as a novel therapeutic against chronic HBV infection.

Characterization of risk factors and efficacy of medical management of immune-related hepatotoxicity in real-world patients with metastatic melanoma treated with immune checkpoint inhibitors.

INTRODUCTION: Immune-related hepatitis (ir-hepatitis) is a common side-effect of checkpoint inhibitors (CPIs). Here, we characterise ir-hepatitis in a large cohort of patients with metastatic melanoma (MM) treated with CPIs and describe potential risk factors and efficacy of medical management. METHODS: The retrospective study included a large cohort of patients with MM treated with CPIs between 2010 and 2019. Patients were retrieved from the national Danish Metastatic Melanoma Database. RESULTS: Five hundred twenty one patients were included. Ir-hepatitis was found in 6.8% of patients. Combination therapy was associated with a significantly greater risk than monotherapy. Of all patients, 34.9% with hepatitis had a different hepatitis grading, when based on either alanine transaminase (ALT) or aspartate transaminase (AST) levels. Of all patients, 72.1% with hepatitis received steroid treatment, and two patients received additional second-line immunosuppressants. Of all patients, 35.5% experienced hepatitis relapse during steroid tapering. Of all patients, 18.6% and 25% of patients with grade ≥2 and ≥ III3, respectively, developed hepatitis within 7 days after finishing an antibiotic treatment for infection. Patients (62.5%) who received a cumulative dose of >4000 mg steroid experienced cancer progression, compared with 22.7% of patients treated with <4000 mg. CONCLUSION: Several observations of clinical importance were made. Infection and antibiotic treatment during CPIs could be a possible risk factor for developing ir-hepatitis. Severity of ir-hepatitis is potentially underestimated in a significant number of patients, if only one liver enzyme is measured. The role of second-line immunosuppressants needs to be further investigated because of the high risk of hepatitis relapse during steroid tapering and the potential negative impact of cumulative steroid dose on response to CPIs.

Acupuncture stimulation attenuates TNF-α production via vagal modulation in the concanavalin A model of hepatitis.

BACKGROUND: A growing body of evidence shows that neuronal activity is involved in modulating the efficacy of acupuncture therapy. However, it has been seldom investigated whether neuronal activity following acupuncture stimulation is effective at regulating hepatic inflammation. OBJECTIVE: Using the concanavalin A (ConA) model of hepatitis, we investigated the regulation of inflammatory cytokine tumor necrosis factor (TNF)-α in the liver tissue and the blood after acupuncture stimulation at ST36. METHODS: Mice were subjected to ConA injection, acupuncture stimulation at ST36 by manual acupuncture (MA) or electroacupuncture (EA) procedures, and vagotomy (VNX). Liver tissue and blood were collected for TNF-α analysis. TNF-α mRNA was analyzed by real-time polymerase chain reaction (PCR), and TNF-α, CD11b, CD68, and Erk1/2 proteins were analyzed by Western blotting, immunofluorescence staining, and enzyme-linked immunosorbent assay. RESULTS: TNF-α mRNA and protein were induced in CD11b-positive hepatic cells and the plasma at 6-24 h after ConA injection. The application of MA or EA was very effective at attenuating the production of TNF-α. Anti-inflammatory effects of acupuncture were greatly suppressed by VNX in ConA-injected animals, suggesting the requirement of vagus nerve activity in acupuncture-mediated anti-inflammatory responses. Electrical stimulation of the sciatic nerve (SNS) resulted in an anti-inflammatory effect similar to acupuncture stimulation. In parallel with TNF-α, production of phospho-Erk1/2, which was induced in the liver tissue, was downregulated by MA and EA in liver cells. CONCLUSION: The regulatory effects of acupuncture stimulation on inflammatory responses in the liver may be modulated through the activation of the vagus nerve pathway.