Multimodal decoding of human liver regeneration.

The liver has a unique ability to regenerate1,2; however, in the setting of acute liver failure (ALF), this regenerative capacity is often overwhelmed, leaving emergency liver transplantation as the only curative option3-5. Here, to advance understanding of human liver regeneration, we use paired single-nucleus RNA sequencing combined with spatial profiling of healthy and ALF explant human livers to generate a single-cell, pan-lineage atlas of human liver regeneration. We uncover a novel ANXA2+ migratory hepatocyte subpopulation, which emerges during human liver regeneration, and a corollary subpopulation in a mouse model of acetaminophen (APAP)-induced liver regeneration. Interrogation of necrotic wound closure and hepatocyte proliferation across multiple timepoints following APAP-induced liver injury in mice demonstrates that wound closure precedes hepatocyte proliferation. Four-dimensional intravital imaging of APAP-induced mouse liver injury identifies motile hepatocytes at the edge of the necrotic area, enabling collective migration of the hepatocyte sheet to effect wound closure. Depletion of hepatocyte ANXA2 reduces hepatocyte growth factor-induced human and mouse hepatocyte migration in vitro, and abrogates necrotic wound closure following APAP-induced mouse liver injury. Together, our work dissects unanticipated aspects of liver regeneration, demonstrating an uncoupling of wound closure and hepatocyte proliferation and uncovering a novel migratory hepatocyte subpopulation that mediates wound closure following liver injury. Therapies designed to promote rapid reconstitution of normal hepatic microarchitecture and reparation of the gut-liver barrier may advance new areas of therapeutic discovery in regenerative medicine.

A disease-associated gene desert directs macrophage inflammation through ETS2.

Increasing rates of autoimmune and inflammatory disease present a burgeoning threat to human health1. This is compounded by the limited efficacy of available treatments1 and high failure rates during drug development2, highlighting an urgent need to better understand disease mechanisms. Here we show how functional genomics could address this challenge. By investigating an intergenic haplotype on chr21q22-which has been independently linked to inflammatory bowel disease, ankylosing spondylitis, primary sclerosing cholangitis and Takayasu's arteritis3-6-we identify that the causal gene, ETS2, is a central regulator of human inflammatory macrophages and delineate the shared disease mechanism that amplifies ETS2 expression. Genes regulated by ETS2 were prominently expressed in diseased tissues and more enriched for inflammatory bowel disease GWAS hits than most previously described pathways. Overexpressing ETS2 in resting macrophages reproduced the inflammatory state observed in chr21q22-associated diseases, with upregulation of multiple drug targets, including TNF and IL-23. Using a database of cellular signatures7, we identified drugs that might modulate this pathway and validated the potent anti-inflammatory activity of one class of small molecules in vitro and ex vivo. Together, this illustrates the power of functional genomics, applied directly in primary human cells, to identify immune-mediated disease mechanisms and potential therapeutic opportunities.

Arbovirus serosurvey (Orthobunyavirus, Flavivirus, and Alphavirus) in a draft horse population from Santa Fe, Argentina (2013-2016).

In the present study, we serosurveyed the exposure of 222 draft horses to different arboviruses in the city of Santa Fe, Argentina. Plaque reduction neutralization tests confirmed exposure to Fort Sherman virus (FSV), Saint Louis encephalitis virus (SLEV), West Nile virus (WNV), and Río Negro virus (RNV). Apparently, Western and Eastern equine encephalitis viruses did not circulate in the population tested. The confirmation of five seroconversions for WNV, FSV, and SLEV and the association between prevalence and age are indicative of recent circulation. These results highlight the importance of considering draft horses in arboviral surveillance in urban and rural areas of developing countries.

Liver Transplantation After Ex Vivo Normothermic Machine Preservation: A Phase 1 (First-in-Man) Clinical Trial.

The number of donor organs suitable for liver transplantation is restricted by cold preservation and ischemia-reperfusion injury. We present the first patients transplanted using a normothermic machine perfusion (NMP) device that transports and stores an organ in a fully functioning state at 37°C. In this Phase 1 trial, organs were retrieved using standard techniques, attached to the perfusion device at the donor hospital, and transported to the implanting center in a functioning state. NMP livers were matched 1:2 to cold-stored livers. Twenty patients underwent liver transplantation after NMP. Median NMP time was 9.3 (3.5-18.5) h versus median cold ischaemia time of 8.9 (4.2-11.4) h. Thirty-day graft survival was similar (100% NMP vs. 97.5% control, p = 1.00). Median peak aspartate aminotransferase in the first 7 days was significantly lower in the NMP group (417 IU [84-4681]) versus (902 IU [218-8786], p = 0.03). This first report of liver transplantation using NMP-preserved livers demonstrates the safety and feasibility of using this technology from retrieval to transplantation, including transportation. NMP may be valuable in increasing the number of donor livers and improving the function of transplantable organs.

Trans-physeal anterior cruciate ligament reconstruction in adolescents.

PURPOSE: The aim of the study was to evaluate, in a group of adolescents, the onset of varus-valgus deviations in the sagittal plane after performing a trans-tibial trans-epiphyseal technique of ACL reconstruction with a follow-up of at least 2 years. METHODS: Seventy-one patients aged 12-15 years old (Tanner scale 3 and 4) have undergone ACL reconstruction with STG using arthroscopy. All patients were evaluated clinically using the visual analogue scale (VAS), the Lysholm score and the Tegner activity score at the time of surgery. All patients were reevaluated after a follow-up period of at least 2 years (T1) using the VAS, the Lysholm score, the Tegner activity score and radiographic studies in order to compare the operated limb with the healthy control limb. RESULTS: Valgus difference exceeding 2° in the knee axis between the operated limb and the healthy control limb was observed only in three patients (4.2%: 95% CI 0.88-11.86%). The average difference was <1° (0.3°, 95% CI 0.0-0.55). CONCLUSION: The trans-tibial trans-epiphyseal technique of ACL reconstruction, according to the results obtained, seems to be a valid alternative procedure, when performed by a skilled orthopaedic surgeon, offering an excellent safety profile and at the same time very good clinical results. LEVEL OF EVIDENCE: IV.

High accuracy in knee alignment and implant placement in unicompartmental medial knee replacement when using patient-specific instrumentation.

PURPOSE: The influence of patient-specific instrumentations on the accuracy of unicompartmental medial knee replacement remains unclear. The goal of this study was to examine the ability of patient-specific instrumentation to accurately reproduce postoperatively what the surgeon had planned preoperatively. METHODS: Twenty consecutive patients (20 knees) who suffered from isolated unicompartmental medial osteoarthritis of the knee and underwent medial knee replacement using newly introduced magnetic resonance imaging-based patient-specific instrumentation were assessed. This assessment recorded the following parameters: (1) the planned and the postoperative mechanical axis acquired through long-leg AP view radiographies; (2) the planned and the postoperative tibial slope acquired by means of standard AP and lateral view radiographies; and (3) the postoperative fit of the implanted components to the bone in coronal and sagittal planes. The hypothesis of the study was that there was no statistically significant difference between postoperative results and preoperatively planned values. RESULTS: The study showed that (1) the difference between the postoperative mechanical axis (mean 1.9° varus ± 1.2° SD) and the planned mechanical axis (mean 1.8° varus ± 1.2° SD) was not statistically significant; (2) the difference between the postoperative tibial slope (mean 5.2° ± 0.6° SD) and the planned tibial slope (mean 5.4° ± 0.6° SD) was statistically significant (p = 0.008); and (3) the postoperative component fit to bone in the coronal and sagittal planes was accurate in all cases; nevertheless, in one knee, all components were implanted one size smaller than preoperatively planned. Moreover, in two additional cases, one size thinner and one size thicker of the polyethylene insert were used. CONCLUSIONS: This study suggests that overall patient-specific instrumentation was highly accurate in reproducing postoperatively what the surgeon had planned preoperatively in terms of mechanical axis, tibial slope and component fit to bone. LEVEL OF EVIDENCE: IV.

Why menisci show higher healing rate when repaired during ACL reconstruction? Growth factors release can be the explanation.

PURPOSE: Healing rate of meniscus repair is higher when the suture is associated with anterior cruciate ligament reconstruction. A possible explanation can be a different pattern of release of growth factors between anterior cruciate ligament reconstruction and isolated meniscus surgery. Hypothesis of this study is that the concentrations of bFGF, TGF-ß and platelet-derived growth factor (PDGF) in joint fluid, immediately after single-bundle anterior cruciate ligament reconstruction and arthroscopic partial meniscectomy, can be different. METHODS: Twenty consecutive patients underwent partial medial meniscectomy and twenty consecutive patients underwent single-bundle anterior cruciate ligament reconstruction with hamstring grafts were enrolled in the study. Thirty minutes after the end of the surgical procedure, a sample of joint fluid, as well of venous blood, was collected from all the patients. Concentrations of growth factors were determined by enzyme-linked immunosorbent assay. RESULTS: The peripheral blood concentration of TGF-ß, bFGF and PDGF was comparable between partial meniscectomy and anterior cruciate ligament reconstruction groups. No differences between the two surgical techniques were also found in term of TGF-ß and bFGF joint fluid concentration, whereas joint PDGF concentration of anterior cruciate ligament reconstruction patients was significantly higher than the one found in partial meniscectomy patients. CONCLUSIONS: A significant growth factors release was detected in the knee joint during arthroscopic surgery. PDGF concentration was significantly higher in anterior cruciate ligament reconstructed knee than in the meniscectomy group. PDGF can play an important role enhancing the healing response of meniscus suture and can be one of the biological reasons of the higher meniscal healing rate in anterior cruciate ligament reconstructed knee.

Autologous collagen-induced chondrogenesis technique (ACIC) for the treatment of chondral lesions of the talus.

PURPOSE: Autologous collagen-induced chondrogenesis technique (ACIC) combines microfractures with the use of an injectable atelocollagen matrix that allows performing the whole cartilage repair treatment arthroscopically. The aim of this study was to evaluate the in vitro cytocompatibility of this biomaterial using human bone marrow mesenchymal stem cells and human chondrocytes. Moreover, the preliminary data of five patients affected by chondral lesion of the talus treated with the ACIC technique are shown. METHODS: Human bone marrow mesenchymal stem cells and human chondrocytes were seeded on solid and pre-solid atelocollagen scaffolds. Cell-scaffold constructs were cultured for 7 days and then prepared for histological analyses. Arthroscopic ACIC was performed in five patients affected by chondral lesions of the talus; they were clinically evaluated with AOFAS, VAS and Tegner score before and then after 6 months from surgery. RESULTS: In vitro results showed that both bone marrow mesenchymal stem cells and chondrocytes were able to efficiently colonize the whole construct, from the surface to the core, only when seeded on the pre-solid atelocollagen scaffold, but not on its solid form. No adverse events were observed in the patients treated with the ACIC technique; a significant improvement in VAS pain scale and in AOFAS score was found at 6 months follow up. CONCLUSION: Injectable atelocollagen can be considered a feasible scaffold for cartilage repair treatment, in particular if used in its pre-solid form. ACIC leads to good clinical results in the treatment for chondral lesions of the talus even if longer follow-up and a higher number of patients are necessary to confirm these data. LEVEL OF EVIDENCE: IV.

Human liver regeneration is characterized by the coordinated expression of distinct microRNA governing cell cycle fate.

In the absence of adequate compensatory regeneration, overwhelming liver damage can cause acute liver failure (ALF) and death without emergent liver transplantation (LT). Auxiliary LT produces satisfactory outcomes in this setting, with the prospect of native liver regeneration sustaining long-term survival. Since animal models only partially recapitulate human liver regeneration, we investigated the molecular mechanisms controlling it in this unique LT setting, as an exemplar of human liver regeneration. We demonstrate coordinated changes in expression of microRNA (miRNA) during regeneration that drive proliferation, innate immunity and angiogenesis. In contrast, failed regeneration in a similar cohort is associated with distinct miRNA enforcing cell cycle inhibition and DNA methylation. The miRNA expression associated with successful or failed regeneration when recapitulated in vitro, triggered expression of cardinal regeneration-linked genes promoting cell cycle entry or inhibition, respectively. Furthermore, inhibition of miRNA 150, 663 and 503, whose downregulation is associated with successful regeneration, induced cell proliferation which a key determinant of successful regeneration. Our data indicate that human liver regeneration may be orchestrated by distinct miRNA controlling key regeneration-linked processes including hepatocyte proliferation. To our knowledge this is the first characterization of molecular processes associated with human liver regeneration.

Modified autologous matrix-induced chondrogenesis (AMIC) for the treatment of a large osteochondral defect in a varus knee: a case report.

This paper presents a case report of a 27-year-old male patient affected by a large osteochondral defect of the medial femoral condyle (6 cm(2)) in a varus knee. He was treated with a combined approach consisting of high tibial osteotomy and autologous matrix-induced chondrogenesis technique enhanced by a bone marrow-enriched bone graft. Twelve months after surgery, the patient reported considerable reduction in pain and significant increase in his quality of life. A hyaline-like cartilage completely covered the defect and was congruent with the surrounding condyle cartilage as revealed by MRI and by a second-look arthroscopy. Level of evidence IV.

Short communication: Prevalence of deleterious variants causing recessive disorders in Italian Chianina, Marchigiana and Romagnola cattle.

In the last two decades, the molecular cause of six monogenic autosomal recessive disorders has been identified in native Italian beef cattle: two different ATP2A1 variants for the pseudomyotonia congenita, the first in Chianina and Romagnola (PMT1) and the second in Romagnola (PMT2); a KDM2B variant for the paunch calf syndrome (PCS) in Marchigiana and Romagnola; a NID1 variant for the congenital cataract (CC) in Romagnola; a LAMB1 variant for the hemifacial microsomia (HFM) in Romagnola; an ABCA12 variant for the ichthyosis fetalis (IF) in Chianina and a FA2H variant for the ichthyosis congenita (IC) in Chianina. The aim of this study was to evaluate the potential impact of these disorders in the affected Italian populations. For this purpose, 3331 Chianina, 2812 Marchigiana and 1680 Romagnola bulls born in the last 40 years were considered. The allelic frequency (AF) of the variant for PMT1 was 1.0% in Romagnola, 4.6% in Marchigiana and 5.9% in Chianina. The AF of the variant for PMT2 was 3.3% in Romagnola and 0% in the other two breeds. The AF of the variant for PCS was 11.7% in Romagnola, 2.0% in Marchigiana and 0% in Chianina. The AF of the variants for CC, HFM, IF and IC resulted below 3%, being the variants detected only in the breed populations in which they were previously reported. Considering a selected male population in the single breed, Chianina showed carrier prevalence of 11.9% for PMT1, 7.7% for IC and 6.4% for IF. Romagnola showed carrier prevalence of 23.4% for PCS, 6.7% for PMT2, 4.1% for HFM, 3.2% for CC and 2.0% for PMT1. Marchigiana showed carrier prevalence of 9.1% for PMT1 and 4.0% for PCS. With respect to the Romagnola cattle, the concerning presence of a total of five defect alleles in the population hampers a general approach based on the prevention of carriers from artificial insemination. However, identification of carriers may allow conscious mating to prevent the risk of homozygous descendants as well as the spread of heterozygous offspring. Therefore, systematic genotyping for all seven known harmful alleles is recommended to prevent risk mating between carriers, in particular to avoid the occurrence of affected offspring.

High articular levels of the angiogenetic factors VEGF and VEGF-receptor 2 as tissue healing biomarkers after single bundle anterior cruciate ligament reconstruction.

Various factors may account for the positive association between meniscal repair and anterior cruciate ligament reconstruction, one being the modulation of healing response of meniscal fibrochondrocytes by growth factors released with intra-articular bleeding and fibrin clot formation. Analysis of vascular endothelial growth factor (VEGF) and its receptors, VEGFR1 and VEGFR2, may be useful in the clinical assessment of bone and soft-tissue remodeling. We measured systemic and local levels of VEGF (VEGF165), VEGFR1 and VEGFR2 after either arthroscopic partial meniscectomy (APM) or single-bundle anterior cruciate ligament reconstruction (ACLR) in order to determine the local effect of bone tunnelling and notchplasty on the release of these growth factors. The study population included 40 patients: 20 consecutive patients had undergone ACLR with hamstring grafts and 20 had undergone APM. Thirty minutes after the end of the operation, knee joint fluid samples were collected via the drainage tube and at the same time venous blood samples were drawn. In both sets of samples, VEGF, VEGFR1 and VEGFR2 concentrations were determined by enzyme-linked immunosorbent assay (ELISA). No significant differences in VEGF, VEGFR1 or VEGFR2 concentrations in the venous blood were observed between the two treatment groups. In contrast, VEGF and VEGFR2 levels were significantly higher in the knee joint fluid of the ACLR group; furthermore, VEGF and VEGFR1 were significantly higher in the knee joint fluid than in the venous blood, whereas VEGFR2 was lower in the knee joint fluid than in the venous blood. Local release of VEGF and its angiogenetic receptor VEGFR2, but not the negative regulator VEGFR1, was significantly higher after ACLR than after APM, indicating a better vasculogenic potential for enhanced bone-graft and meniscus healing. These results could suggest that VEGF and VEGFRs could be considered as good biomarkers of tissue healing after knee joint surgery.

Outcomes of severe pregnancy-related liver disease: refining the role of transplantation.

Severe liver disease in pregnancy is generally considered to have a favorable prognosis. The limited data available have not yielded disease-specific prognostic criteria or guidance on who should undergo liver transplantation (LT). We retrospectively evaluated 54 admissions with pregnancy-related liver disease to (1) evaluate if any admission parameters were associated with death and/or transplantation and (2) identify maternal complications. Eighteen had acute fatty liver of pregnancy and 32 had hypertension/eclampsia related disease. Seven patients (13%) died and four (7%) underwent LT. Survival rates were 43/48 if not listed for LT and 4/6 if listed. Of the four transplanted, three survived. Patients who died and/or underwent LT were more likely to have encephalopathy (p = 0.04) and hyperlactaemia (p = 0.03). Serum lactate was the best discriminant (ROC AUC 0.84). An admission lactate greater than 2.8mg/dL had 73% sensitivity and 75% specificity for predicting death or LT. The addition of encephalopathy to this parameter increased sensitivity and specificity to 90% and 86%, respectively. The King's College criteria were not effective in predicting outcome. This study confirms the overall favorable prognosis in pregnancy-related liver failure but indicates that elevated lactate levels in the presence of encephalopathy best identify patients at greatest risk of death or LT.

Prospective comparison of Fibroscan, King's score and liver biopsy for the assessment of cirrhosis in chronic hepatitis C infection.

Historically, liver biopsy (LB) was the sole method to evaluate the severity of hepatic fibrosis in patients with chronic hepatitis C infection. However, LB is expensive and associated with a risk of severe complications. Therefore, noninvasive tests have been developed to assess the severity of liver fibrosis. The accuracy of Fibroscan (FS) and King's score (KS) was evaluated individually and in combination using liver histology as the reference standard. One hundred and eighty-seven patients were identified who had undergone a biopsy with a diagnosis of chronic hepatitis C virus (HCV) mono-infection (HCV RNA-positive by RT-PCR), attending King's College Hospital (n = 88) or the Royal Free Hospital (n = 99) (London) between May 2006 and December 2007. Liver fibrosis was scored using the Ishak method; significant fibrosis was defined as Ishak fibrosis stage F3-F6, and cirrhosis defined as Ishak fibrosis F5-F6. The diagnostic accuracy of each test was assessed by area under receiver operator characteristic curves (AUROC). Median age was 49 years (43-54) and 115 (61%) were male. The AUROC for FS, KS and FS + KS for the diagnosis of Ishak F3-F6 were 0.83, 0.82 and 0.85, respectively and for the diagnosis of cirrhosis (>or=F5) were 0.96, 0.89 and 0.93, respectively. The negative predictive values for the diagnosis of cirrhosis using the optimal cut-off results for fibrsocan (10.05 kPa), KS (24.3) and the two combined (26.1) were 98%, 91% and 94%, respectively. The noninvasive markers and, particularly, FS were effective tests for the prediction of cirrhosis in chronic hepatitis C. Both KS and FS also had clinical utility for the prediction of Ishak fibrosis stages F3-F6.

A simple, noninvasive test for the diagnosis of liver fibrosis in patients with hepatitis C recurrence after liver transplantation.

Recurrent hepatitis C is a common cause of graft loss in patients undergoing liver transplantation, and serial protocol liver biopsies have been used to identify patients at risk of graft loss from rapid fibrosis progression. The aim of this study was to derive a simple noninvasive index to predict fibrosis in patients with recurrent hepatitis C post-transplant. A retrospective study was performed assessing serial liver biopsies for post-transplant chronic hepatitis C infection. One hundred eighty-five patients were included in the analysis; median age 53 years (interquartile range 48-59) and 140 (76%) were male. Liver histology showed 53 (29%) had Ishak fibrosis stages F0/F1, 31 (17%) had F2, 29 (16%) had F3, 19 (10%) had F4 and 53 (29%) had F5/F6. The London Transplant Centres' (LTC) score was derived combining aspartate aminotransferase (AST IU/L), time from liver transplant (TFLT months), international normalized ratio and platelets. Diagnostic accuracy of the LTC score was assessed using area under receiver-operating characteristic (ROC) curves. The area under the ROC curve for moderate fibrosis (F >or= 2) was 0.78 (95% CI, 0.70-0.86; P < 0.0001), for advanced fibrosis (F4-6) was 0.80 (95% CI, 0.72-0.87; P < 0.0001) and for cirrhosis was 0.80 (95% CI, 0.72-0.88; P < 0.0001). An optimal cut-off value of 6.3 distinguished patients with no or mild fibrosis (F

Do steatosis and steatohepatitis impact on sustained virological response (SVR) rates in patients receiving pegylated interferon and ribavirin for chronic hepatitis C infection?

The impact of steatosis on treatment response in chronic hepatitis C infection is controversial. The aim of this study was to determine whether steatosis +/- steatohepatitis on pre-treatment liver biopsy influenced sustained virological response (HCV RNA negative 6 months after completing therapy) in patients with chronic hepatitis C infection treated with pegylated interferon-alpha and ribavirin. One hundred and seventy-nine patients, median age 46 years (interquartile range 40-52), treated between 2001 and 2005. Histological evidence of steatosis was present in 93 patients (52%) and steatohepatitis in 33 patients (18%), 31 patients (17.3%) were cirrhotic. There were 106 (59%) responders, who were similar to non-responders in respect to gender, age, and pre-treatment ALT. On univariate analysis, infection with genotype 2 or 3 was associated with sustained virological response (odds ratio 6.5 (95% CI, 3.3-12.5); P < 0.0001), whereas cirrhosis and patient weight were associated with a reduced response (odds ratios 0.23 (95% CI, 0.11-0.48); P < 0.0001, and 0.97 (95% CI, 0.95-0.99); P < 0.01, respectively); steatohepatitis but not steatosis impacted on the likelihood of achieving sustained virological response (odds ratio 0.37 (95% CI, 0.17-0.77); P = 0.009, and P = 0.18, respectively). Multivariate analysis revealed that infection with genotype 1 or 4 (odds ratio 0.09 (95% CI, 0.03-0.32); P < 0.001) and pre-treatment weight (odds ratio 0.94 (95% CI, 0.90-0.98); P = 0.002) were the only variables associated independently with sustained virological response. In chronic hepatitis C infection, although steatosis was associated with steatohepatitis, neither was shown to affect sustained virological response, which was influenced by genotype, patient weight and the presence of cirrhosis.

Growth factors in the management of sport-induced tendinopathies: results after 24 months from treatment. A pilot study.

AIM: The efficacy of PRP in the treatment of tendinopathies has been already studied both in in vitro and in clinical studies. This paper describes the local and the systemic effects of US-guided autologous PRP (Platelet Rich Plasma) injections in chronic tendinopathies in sportspersons. METHODS: Fifteen patients (13 male, 2 female) between 17 and 68 years old, affected by chronic tendinopathies at different sites were treated with an echographically guided injection of autologous PRP within the pathological area of the tendons. VISA score and MRI data were collected pre interventions and after 90 days and 24 months from treatment. Changes in different inteleukins (ILs), tumour necrosis factor α (TNF α), interferon γ, vascular endothelial growth factor (VEGF), endothelial growth factor (EGF), chemokine (C-C motif) ligand 2 (CCL2), were analysed at four time points in the peripheral blood of five patients. RESULTS: After 90 days the VISA score significantly improved from 36±12 (range 21-64) to 74±17 (range 40-92). Reduction of irregularities was found in 80% of the tendons. After 24 months patients reported an average VISA score of 73±16 (range 42-100). No changes in IL, TNF α and interferon γ were observed. VEGF, EGF and CCL2 decreased progressively from 30m to 3 h after the treatment and returned to near the baselines after 24 h. CONCLUSION: PRP injection allow an improvement of the clinical symptomatology, which is well maintained at least for two years from treatment. The PRP-based local therapy could influence systems homeostasis and antidoping evaluations, but, in our opinion, it doesn't represent a doping substance in itself.

The impact of hepatic steatosis on the natural history of chronic hepatitis C infection.

Since patients with hepatitis C virus (HCV) often have hepatic steatosis, this retrospective analysis aimed to assess whether steatosis influences fibrosis progression. We studied 112 HCV RNA positive subjects (median age 44, IQR 39-51 years), who had two liver biopsies performed (median biopsy interval 50, 34-74 months). Fibrosis was staged using the Ishak method and steatosis by the Kleiner system (<5% steatosis = S0, 5-33% = S1, 33-66% = S2, and >66% = S3). The subjects were untreated because they had mild fibrosis (n = 59), declined therapy (n = 48), or had co-existing disease precluding treatment (n = 5). On first liver biopsy, 60 (54%) had S0, 34 (30%) had S1, 12 (11%) had S2, and 6 (5%) had S3. Steatosis was associated with genotype 3, odds ratio 4.8 (95% CI 1.3-16.7, P = 0.02). Twenty-three patients (21%) had disease progression on the second biopsy, defined as an increase in Ishak score by > or =1 stage. On univariate analysis, fibrosis progression was associated with older age (P = 0.004), higher AST (P = 0.04), and steatosis (P = 0.005) but on multivariate analysis, only baseline steatosis was significant, odds ratio 14.3 (2.1-111.1, P = 0.006). Kaplan-Meier analysis demonstrated that steatosis impacted on time to progression to both significant fibrosis (Ishak > or =F3) and cirrhosis (Ishak F5-6) (P = 0.001 and P = 0.049, respectively). The finding that steatosis was significantly associated with fibrosis progression indicates that, independent of baseline fibrosis stage, patients should be considered for anti-viral treatment if steatosis is present. Furthermore, strategies to reduce steatosis may have a beneficial effect on fibrosis progression and, therefore, patient outcome.

The expression and function of NKG2D molecule on intrahepatic CD8+ T cells in chronic viral hepatitis.

The natural killer (NK) cell receptor, NKG2D is a member of the c-type lectin-activating receptor family. It is expressed by all NK cells and by a sub-population of CD8+ T cells. NKG2D engagement with its ligands directly activates NK cells and acts as a co-stimulator on CD8+ T cells. Recent reports, however, have demonstrated a role for NKG2D in direct T-cell activation in chronic inflammation. The aim of this study was to investigate the pattern of expression and the functional role of NKG2D on circulating and intrahepatic CD8+ T cells in chronic viral hepatitis. Peripheral blood lymphocytes and intrahepatic lymphocytes from 45 patients with chronic viral hepatitis (HBV and HCV) were studied. Phenotypic NKG2D expression and its functional ability to activate intrahepatic and circulating lymphocytes were analysed. Intrahepatic CD8+ T cells display increased NKG2D expression in chronic viral hepatitis in comparison with circulating CD8+ T cells. NKG2D co-stimulates intrahepatic CD8+ T cells and hepatitis B virus-specific CD8+ T cells. However, we could not demonstrate an ability to directly activate CD8+ T cells through the NKG2D signalling pathway alone. NKG2D is up-regulated on intrahepatic CD8+ T cells in type B and C chronic viral hepatitis; however, its function appears to be restricted to that of a co-stimulatory molecule.