Intrahepatic Granuloma Research Articles

Secondary Sclerosing Cholangitis in the Setting of Elective Bariatric Surgery

Secondary sclerosing cholangitis (SSC) is a rare, chronic, progressive condition of biliary tree fibrosis after an insult. It is a rare cause of preventable liver cirrhosis. Of 31 reported cases in the past decades most presented after surgical trauma, other causes include chronic cholestatis, cholangitis or ischemia.1 A 45-year-old female with a history of idiopathic pulmonary fibrosis presented with prolonged hyperbilirubinemia after gastric sleeve bypass, cholecystectomy, and hiatal hernia repair three months prior to admission. She presented with jaundice and elevated total bilirubin, direct bilirubin and alkaline phosphatase at 3.6 mg/dL, 3.0 mg/dL, and 217 U/L, respectively. MRCP revealed a stricture near the level of the cystic duct. ERCP showed a focal stricture at the distal common hepatic duct (CHD) requiring stent (Image 1). Due to worsened hyperbilirubinemia, a repeat ERCP was completed which revealed a highgrade stricture at the CHD that required dilation and another stent. Liver biopsy was also performed and showed canalicular cholestatis without intra-hepatic granulomas or ductal lesions, suggesting extrahepatic ductal obstruction (Image 2). She then underwent hepaticojejunostomy with surgical pathology of the common bile duct revealing a post-cholecystectomy traumatic neuroma. She was discharged after HIDA scan revealed no evidence of biliary leak, but returned to clinic 14 days later with progressive jaundice, new ascites, bilateral lower extremity edema, and acute kidney injury (AKI) with elevated creatinine of 1.76 mg/dL (baseline 0.4 mg/dL). A third liver biopsy was performed which showed findings consistent with portal edema, mixed inflammation, cholestasis and fibrosis (Image 3). Her bilirubin slowly improved without further intervention, but remained elevated at 14.2 mg/dL and she ultimately required dialysis. This patient was diagnosed with SSC in the setting of biliary tract fibrosis subsequent to traumatic injury of the biliary tract after cholecystectomy. Our presentation is unique as SSC was complicated by hemodialysis dependent renal dysfunction with microscopic evidence of acute tubular necrosis. This case is consistent with the common cause, histological characteristics and chronic nature of SSC. Future research is required to elucidate other organ complications that management of this disease may be optimized. 1- Ruemmele et. al. Secondary sclerosing cholangitis. Nat. Rev. Gastroenterol. Hepatol. 6, 287-295 (2009).Figure: ERCP showing common hepatic duct stricture.Figure: Cholestasis and edema.Figure: Portal tract with edema and fibrosis.

24-nor-ursodeoxycholic acid ameliorates inflammatory response and liver fibrosis in a murine model of hepatic schistosomiasis

Intrahepatic granuloma formation and fibrosis characterize the pathological features of Schistosoma mansoni infection. Based on previously observed substantial anti-fibrotic effects of 24-nor-ursodeoxycholic acid (norUDCA) in Abcb4/Mdr2(-/-) mice with cholestatic liver injury and biliary fibrosis, we hypothesized that norUDCA improves inflammation-driven liver fibrosis in S. mansoni infection. Adult NMRI mice were infected with 50 S. mansoni cercariae and after 12 weeks received either norUDCA- or ursodeoxycholic acid (UDCA)-enriched diet (0.5% wt/wt) for 4 weeks. Bile acid effects on liver histology, serum biochemistry, key regulatory cytokines, hepatic hydroxyproline content as well as granuloma formation were compared to naive mice and infected controls. In addition, effects of norUDCA on primary T-cell activation/proliferation and maturation of the antigen-presenting-cells (dendritic cells, macrophages) were determined in vitro. UDCA as well as norUDCA attenuated the inflammatory response in livers of S. mansoni infected mice, but exclusively norUDCA changed cellular composition and reduced size of hepatic granulomas as well as TH2-mediated hepatic fibrosis in vivo. Moreover, norUDCA affected surface expression level of major histocompatibility complex (MHC) class II of macrophages and dendritic cells as well as activation/proliferation of T-lymphocytes in vitro, whereas UDCA had no effect. This study demonstrates pronounced anti-inflammatory and anti-fibrotic effects of norUDCA compared to UDCA in S. mansoni induced liver injury, and indicates that norUDCA directly represses antigen presentation of antigen presenting cells and subsequent T-cell activation in vitro. Therefore, norUDCA represents a promising drug for the treatment of this important cause of liver fibrosis.

TLR9-Dependent and Independent Pathways Drive Activation of the Immune System by Propionibacterium Acnes

Propionibacterium acnes is usually a relatively harmless commensal. However, under certain, poorly understood conditions it is implicated in the etiology of specific inflammatory diseases. In mice, P. acnes exhibits strong immunomodulatory activity leading to splenomegaly, intrahepatic granuloma formation, hypersensitivity to TLR ligands and endogenous cytokines, and enhanced resistance to infection. All these activities reach a maximum one week after P. acnes priming and require IFN-γ and TLR9. We report here the existence of a markedly delayed (1–2 weeks), but phenotypically similar TLR9-independent immunomodulatory response to P. acnes. This alternative immunomodulation is also IFN-γ dependent and requires functional MyD88. From our experiments, a role for MyD88 in the IFN-γ-mediated P. acnes effects seems unlikely and the participation of the known MyD88-dependent receptors, including TLR5, Unc93B-dependent TLRs, IL-1R and IL-18R in the development of the alternative response has been excluded. However, the crucial role of MyD88 can partly be attributed to TLR2 and TLR4 involvement. Either of these two TLRs, activated by bacteria and/or endogenously generated ligands, can fulfill the required function. Our findings hint at an innate immune sensitizing mechanism, which is potentially operative in both infectious and sterile inflammatory disorders.

Innate, antigen‐independent role for T cells in the activation of the immune system by Propionibacterium acnes

Propionibacterium acnes is a human commensal but also an opportunistic pathogen. In mice, P. acnes exerts strong immunomodulatory activities, including formation of intrahepatic granulomas and induction of LPS hypersensitivity. These activities are dependent on P. acnes recognition via TLR9 and subsequent IL-12-mediated IFN-gamma production. We show that P. acnes elicits IL-12p40 and p35 mRNA expression in macrophages, and IFN-gamma mRNA in liver CD4(+) T cells and NK cells. After priming with P. acnes, CD4(+) T cells serve as the major IFN-gamma mRNA source. In the absence of CD4(+) T cells, CD8(+) T cells (regardless of antigenic specificity) or NK cells can produce sufficient IFN-gamma to induce the P. acnes-driven immune effects. Moreover, in the absence of alpha beta T cells, gamma delta T cells also enable the development of strongly enhanced TNF-alpha and IFN-gamma responses to LPS and intrahepatic granuloma formation. Thus, under microbial pressure, different T-cell types, independent of their antigen specificity, exert NK-cell-like functions, which contribute decisively to the activation of the innate immune system.

Echinococcus multilocularis infection and TNF inhibitor treatment in a patient with rheumatoid arthritis

Sir, TNFa blocking agents should not be used in patients with high risk of infections whose containment is macrophage/ granuloma dependent, such as mycobacteria, coccidiomycosis or histoplasmosis [1]. In echinococcosis, Th1 cytokines are also important for host defense [2, 3]. It has been shown that TNFa mRNA is located in macrophages in the periparasitic area of the liver [4] leading to the development of an intrahepatic granuloma surrounding the parasite tissue [5]. Otherwise, antibody production in early infection may be stimulated by a T-cell independent mechanism [6]. However, to our best knowledge, cases of the evolution of echinococcosis during TNF inhibitor treatment have not been reported so far. We present a patient with rheumatoid arthritis (RA), who developed echinococcus abscess for

Non-cell Corynebacterium parvum generated by nanotechnology: A promising immunomodulator with less side effects

Corynebacterium parvum (CP), a kind of immunomodulator, has been well documented in immunotherapy to tumor. However, severe side effects, such as intrahepatic granulomas and scleromes in injected areas, restrict its clinical application. To minimize side effects of CP, a non-cell Corynebacterium parvum product (NCPP) was prepared by disposing CP with Nanotechnology. In present study, we compared effect of NCPP with that of CP and found: (1) NCPP with non-formaldehyde residue was easy to be absorbed without swelling and sclerome in local injected areas; (2) NCPP caused no obvious liver injury in murine and macaques; (3) NCPP maintained powerful anti-tumor activity, increased splenic index, elevated macrophage number, phagocytosis and production of hydrogen peroxide (H 2O 2), and nitric oxide (NO); (4) Importantly, unparallel CP, NCPP could stimulate macrophages to produce low level of tumor necrosis factor-α(TNF-α) but high level of interferon-γ (IFN-γ), an inhibitor to fibrosis. Our study has led to the view that NCPP will evolve into a new valuable immunomodulator for clinical application.

Propionibacterium acnes-induced hepatic granuloma formation is impaired in mice lacking tetraspanin CD9

The granuloma is a host defence response to persistent pathogenic irritants. In the process of granuloma formation, the activation, migration, and fusion of macrophages occur locally, but the mechanisms involved remain elusive. Tetraspanins regulate cell migration and fusion by organizing functional molecular complexes in membrane microdomains. Here we investigated the role of tetraspanin CD9 in hepatic granuloma formation. Immunostaining of the liver of untreated wild-type mice showed that CD9 was expressed by vascular endothelial cells and perivenular hepatocytes. When intrahepatic granulomas were induced by intravenous injection of Propionibacterium acnes, hepatocyte CD9 was extensively upregulated, while inflammatory cells constituting granulomas were mostly negative for CD9. Compared with wild-type littermates, CD9-knockout mice showed dissemination of Propionibacterium acnes and reduced number and size of granulomas after the injection. Moreover, production of granuloma-inducing cytokines, TNF-alpha and IFN-gamma, was delayed and chemotactic activity for macrophages was suppressed in the liver of mutant mice. These results suggest that CD9 is one of the proteins that promotes granuloma formation in the liver.

Clinical Quiz

A 4-year-old boy was referred for evaluation of hepatosplenomegaly. He was diagnosed at age 4months with Weber-Christian syndrome after presenting with panniculitis and fever. He had increasing abdominal girth and hepatosplenomegaly, symmetric large joint synovitis, chronic truncal and facial scaling dermatitis, and failure to thrive for 1 year before evaluation. He had occasional flares of fever, rash, and arthritis, which were treated using nonsteroidal antiinflammatory agents. Physical examination showed a chronically ill child with a height and weight in lower than the fifth percentile. He had obvious hepatosplenomegaly, multiple large joint effusions with elbow contractures, and an erythematous scaling rash on his trunk and scalp. Chest radiography showed hilar fullness. Laboratory evaluation showed the following: white blood count: 7,800/mm3; hemoglobin concentration: 9.2 g/dL; mean corpuscular volume: 64 fl; hematocrit concentration: 28%; erythrocyte sedimentation rate: 6 mm/hr, C-reactive protein concentration: 2.5 mg/dL; aspartate aminotransferase concentration: 80 U/L; alanine aminotransferase concentration: 42 U/L; prothrombin time: 12.7 seconds; and partial thromboplastin time: 32 seconds. Serum glucose, electrolytes, blood urea nitrogen, and creatinine concentrations were within normal ranges. Serology results for Epstein-Barr virus, cytomegalovirus, and syphilis were negative. Abdominal ultrasound showed marked lymphadenopathy in the porta hepatis and mesentery, hepatosplenomegaly, and normal portal blood flow. Percutaneous liver biopsy was performed (Fig. 1 and 2).FIG. 1. No caption available.FIG. 2. No caption available.What is your diagnosis? A. Tuberculosis B. Berylliosis C. Infectious mononucleosis D. Sarcoidosis E. Histoplasmosis Answer: The percutaneous liver biopsy showed noncaseating granulomas with multinucleated giant cells. Inclusions, consistent with Schaumann bodies were seen, as depicted in Figure 2. These are highly supportive, though not definitely diagnostic, of sarcoidosis. A skin biopsy specimen also contained noncaseating granulomas with multinucleated giant cells and similar inclusions. Additional findings included mediastinal and hilar adenopathy seen on the chest computed tomography scan, hypercalciuria, and an increased angiotensin-converting enzyme level at 153 IU/L (normal, 10–34 IU/L). Results of ophthalmologic examination were normal. He was diagnosed with sarcoidosis and treated with corticosteroids. His rash and hepatosplenomegaly resolved within 1 month of treatment, and his polysynovitis is slowly improving. Comment: Sarcoidosis is a chronic, multisystem, granulomatous disease of unknown etiology. It is uncommon in children, with different clinical syndromes depending on the age at presentation. Preschool children tend to have arthritis, dermatitis, and uveitis, whereas, school-age children and adolescents more commonly present with lymphadenopathy, pulmonary disease, and generalized symptoms (1). Diagnosis is suspected on clinical grounds, supported by laboratory studies and confirmed by the demonstration of the noncaseating granulomas, ideally in more than one tissue site. The inability to show an infectious cause by special stains, culture, or serology, and improvement with corticosteroids further supports the diagnosis. Hepatomegaly is present 25 to 40% of the time, and granulomas are found in approximately 80% of liver biopsy specimens in children with sarcoidosis (2). The liver is most often an innocent bystander, becoming enlarged and developing mild cholestasis secondary to the infiltration with granulomas. Intrahepatic cholestasis, hepatic failure, portal hypertension, and Budd Chiari syndrome have been reported in adult patients. In a recent review of 100 adult patients with sarcoidosis who underwent liver biopsy, 100% had intrahepatic granulomas. Various other histologic changes have been reported, including cholestasis (58%), necroinflammatory changes (41%), and vascular abnormalities with sinusoidal dilatation and nodular regenerative hyperplasia (20%). Fibrosis was present in 21% of the biopsy specimens and cirrhosis was present in 6%(3).

Pivotal role of TARC, a CC chemokine, in bacteria-induced fulminant hepatic failure in mice.

Thymus and activation-regulated chemokine (TARC) is a recently identified lymphocyte-directed CC chemokine which specifically chemoattracts T helper type 2 CD4(+) T cells in human. To establish the pathophysiological roles of TARC in vivo, we investigated whether a monoclonal antibody (mAb) against TARC could inhibit the induction of hepatic lesions in murine model using Propionibacterium acnes and lipopolysaccharide (LPS). P. acnes-induced intrahepatic granuloma formation in the priming phase is essential to the subsequent liver injury elicited by a low dose of LPS. The priming phase appears to be dominated by Th1 type immune responses determined by the profile of chemokine and chemokine receptor expression. TARC was selectively produced by granuloma-forming cells, and CC chemokine receptor 4 (CCR4)-expressing CD4(+) T cells migrated into the liver after LPS administration. In vivo injection of anti-TARC mAb just before LPS administration protected the mice from acute lethal liver damage, which was accompanied by a significant reduction of both CCR4 mRNA expression and IL-4 production by liver-infiltrating CD4(+) T cells. Moreover, both TNF-alpha and Fas ligand expressions in the liver were decreased by anti-TARC treatment. These results suggest that recruitment of IL-4-producing CCR4(+) CD4(+) T cells by granuloma-derived TARC into the liver parenchyma may be a key cause of massive liver injury after systemic LPS administration.

Tumor necrosis factor receptor p55 is essential for intrahepatic granuloma formation and hepatocellular apoptosis in a murine model of bacterium-induced fulminant hepatitis.

Accumulating evidence implicates tumor necrosis factor (TNF) and Fas systems in liver injury, although the interaction between these two systems remains to be investigated. In this study, we examined Propionibacterium acnes-primed TNF receptor p55-deficient (TNFRp55-/-) or Fas-deficient MRL/MpJ Lpr/Lpr mice challenged with lipopolysaccharide (LPS). Priming with P. acnes caused mononuclear cell infiltration into the hepatic lobules and granuloma formation in the livers of TNFRp55 wild-type mice. Subsequent LPS challenge caused massive liver injury and a marked increase in transaminase levels, leading to acute lethality in control wild-type mice. In contrast, the same treatment caused few pathological changes in livers of TNFRp55-/- mice, and all animals survived. P. acnes and subsequent LPS challenge induced granuloma formation and apoptotic changes, respectively, in livers of MRL/MpJ Lpr/Lpr mice. However, liver injury was 50% of that in control MRL/MpJ +/+ mice, suggesting some role of the Fas-Fas ligand system in this liver injury model. On the other hand, an agonistic anti-Fas antibody caused massive apoptosis and hemorrhagic changes of the liver without any priming with P. acnes, leading to death in both TNFRp55-/- and control wild-type mice. These results suggest that TNFRp55 but not Fas was involved in P. acnes-induced granuloma formation as well as subsequent LPS-induced liver injury and that TNFRp55 and Fas independently induced apoptosis of hepatocytes in vivo.

IMPAIRED DELAYED HYPERSENSITIVITY IN PRIMARY BILIARY CIRRHOSIS

Primary biliary cirrhosis is a granulomatous disease. Intrahepatic granulomas were found in 29 out of 69 patients, and in 5 of these patients granulomas were found in lymph-nodes from various sites. This indicates that the granulomatous response can be widespread. Skin testing revealed a high incidence of Mantoux negatives in primary biliary cirrhosis compared with controls. Delayed hypersensitivity could be induced with dinitrochlorobenzene in only 46% of patients compared with 94% of controls. Most patients had impaired in-vitro lymphocyte transformation in response to phytohæmagglutinin. These findings indicate that in primary biliary cirrhosis there may be impairment of the normal mechanisms of delayed hypersensitivity. It is suggested that this is a result of the disease process rather than an ætiological factor.