Serum levels of caspase-cleaved cytokeratin 18 (CK18-Asp396) predict severity of liver disease in chronic hepatitis B

The heterogeneity of cirrhosis - systemically assessed endotypes described by fibrosis, apoptosis, and immunoregulatory-related biomarkers

BACKGROUND

Given the heterogeneity of advanced chronic liver disease, assessing disease activity-related biomarkers could aid in classifying cirrhosis endotypes for better patient monitoring and treatment selection.

AIM

To investigate cirrhosis endotypes described by disease activity biomarkers related to fibrogenesis, immune cell activity, apoptosis, and systemic inflammation.

METHODS

The study included plasma EDTA samples from 106 participants with mild, moderate, and severe liver cirrhosis undergoing hepatic venous pressure gradient (HVPG) measurements and 39 healthy control participants. The biomarkers nordicPROC3™ (fibrogenesis), GDF-15, CK18 M30 (apoptosis), CRP (systemic inflammation), nordicCPa9-HNE™ (neutrophil activity), and nordicVICM™ (macrophage activity) were measured.

RESULTS

PROC3, GDF-15, CK18 M30, and CRP increased with cirrhosis severity (p < 0.05-p < 0.0001) and the degree of portal hypertension (p < 0.05-p < 0.01). CPa9-HNE decreased from mild to moderate and mild to severe cirrhosis (p < 0.01-0.0001) and correlated with HVPG (r=-0.53, p < 0.0001). VICM decreased from mild to severe cirrhosis (p < 0.01). A heatmap clustered analysis revealed four potential cirrhosis endotypes, reflecting underlying biological processes.

CONCLUSION

Assessing markers related to active fibrogenesis, apoptosis, immune cell activity, and systemic inflammation revealed distinct molecular patterns among patients with cirrhosis. These findings suggest the presence of potential disease endotypes that could inform future strategies for patient monitoring, treatment selection, and prognostic assessment in cirrhosis management.

Diagnostic Value of Serum Cytokeratin 18 for the Staging of Liver Inflammation and Fibrosis: A Meta-Analysis

BACKGROUND AND AIMS

Accurate assessment of liver inflammation and fibrosis is of vital importance in the clinical management of patients with liver diseases. Our aim is to conduct a meta-analysis to evaluate the diagnostic accuracy of serum cytokeratin 18 (CK18) for staging of liver inflammation and fibrosis against a liver biopsy in adults.

METHODS

We systematically searched articles from eight electronic databases. Two authors independently selected included studies, extracted data, and assessed quality. In our meta-analysis, we used the random-effects meta-analysis model. Publication bias, sensitivity analysis, heterogeneity analysis, and post-test probability were used in this meta study.

RESULTS

A total of 20 studies with 2235 patients were initially found by the search strategies. The pooled sensitivity, specificity, and area under the curve (AUC) of the summary receiver operating characteristic curve were 0.56, 0.81, and 0.810 for significant fibrosis; 0.64, 0.76, and 0.785 for advanced fibrosis; 0.53, 0.76, and 0.830 for cirrhosis; and 0.68, 0.73, and 0.786 for significant inflammation, respectively. High heterogeneity was observed in our meta-analysis because of factors such as the proportion of males, total number, and antigens of CK-18.

CONCLUSION

Serum CK18 had moderate diagnostic value (AUC > 0.7) in different stages of liver fibrosis and significant inflammation, offering a complementary approach to other non-invasive indicators such as serological biomarkers and imaging techniques. Future research should focus on elucidating the role of CK18 in the occurrence and progression of hepatitis and liver fibrosis, particularly in liver diseases with diverse etiologies.

Cytokeratin 18 fragment in liver inflammation and fibrosis: Systematic review and meta-analysis

BACKGROUND

This meta-analysis aimed to summarize the diagnostic accuracy and cut-off values of cytokeratin (CK) 18 measurements, specifically M30 and M65, as candidate biomarkers for the pathological evaluation of biopsy specimens used to stage liver inflammation and fibrosis in patients with chronic liver diseases.

METHODS

Databases were searched for studies collected up to January 11th, 2025. Pooled sensitivity, specificity, area under the receiver-operating characteristic curves, and mean cut-off values were calculated using random-effects models regardless of heterogeneity. A meta-regression analysis and subgroup analysis were performed to explore heterogeneity.

RESULTS

Sixty-three studies comprising 9137 patients were included. The summarized AUROC curve of CK18 M30 for the diagnosis of significant liver inflammation, fibrosis ≥F1, ≥F2, ≥F3, and =F4 according to the METAVIR score system were 0.82, 0.75, 0.78, 0.78 and 0.76, with mean cut-off values of 264.3, 188.0, 276.9, 322.8 and 169.4 U/L. For M65, the summarized AUROC curve for detecting significant liver inflammation, fibrosis ≥F1, ≥F2, and =F4 were 0.79, 0.70, 0.76, 0.64 and 0.72, with mean cut-off values of 541.1, 417.6, 500.1, 424.6 and 674.0 U/L. The subgroup analyses implied that ethnicity may be the primary factor related to heterogeneity in CK18 M30 when applied to detect significant inflammation. Asian patients had values 79.7 U/L higher than those of non-Asian patients (p = 0.0157).

CONCLUSIONS

CK18 M30 and M65 have clinically meaningful accuracy as alternative diagnostic tools for determining liver inflammation and fibrosis using biopsy specimens of patients with steatotic liver disease or viral hepatitis.

REGISTRATION

PROSPERO registration number: CRD42022364598.

Clinical significance of serum Ck18-M65 and M30 levels in patients with chronic hepatitis B combined with nonalcoholic steatohepatitis and liver fibrosis

In this study, we aimed to explore the clinical significance of serum CK18-M65 and CK18-M30 levels in patients with chronic hepatitis B (CHB) complicated by nonalcoholic steatohepatitis (NASH) and liver fibrosis. The observation and control groups comprised 133 patients with CHB complicated by NASH and 50 healthy patients from our hospital, respectively. Liver function indices, including alanine aminotransferase, glutamic aminotransferase, γ-glutamyltransferase, total bilirubin, total protein, and total cholesterol, were determined using an automatic biochemical analyzer. Hyaluronic acid, type III procollagen, type IV collagen, laminin, and CK18-M65 and M30 levels were detected using ELISA. Serum CK18-M65 and M30 levels in patients with CHB complicated by NASH were positively correlated with the liver fibrosis stage (P < .05). While serum CK18-M65 demonstrated a low diagnostic value for liver fibrosis in the S0-1 stage, it exhibited good diagnostic value for S2-3 stage liver fibrosis. Serum CK18-M30 displayed good diagnostic value for S0-1 and S2-3 hepatic fibrosis, particularly for S2-3 hepatic fibrosis. Elevated serum CK18-M65 and CK18-M30 levels in patients with CHB complicated with NASH suggest their potential utility in evaluating the progression of liver fibrosis in this population. In particular, CK18-M30 exhibits superior diagnostic efficiency.

A randomised Phase IIa trial of amine oxidase copper-containing 3 (AOC3) inhibitor BI 1467335 in adults with non-alcoholic steatohepatitis

Non-alcoholic steatohepatitis (NASH) is a progressive, inflammatory liver disease with no approved pharmacological treatment. This Phase IIa, double-blind, placebo-controlled, multicentre trial (ClinicalTrials.gov: NCT03166735) investigated pharmacodynamics and safety of BI 1467335, an amine oxidase copper-containing 3 (AOC3) inhibitor, in adults with NASH from Europe and North America. Participants from 44 centres across the US, Germany, Spain, Belgium, the UK, Netherlands, Canada, France and Ireland were randomised (2:1:1:1:2; 27 July 2017 to 14 June 2019) to daily oral BI 1467335 1 mg (n = 16), 3 mg (n = 16), 6 mg (n = 17), 10 mg (n = 32) or placebo (n = 32) for 12 weeks, with follow-up to Week 16. Primary endpoint was AOC3 activity relative to baseline (%), 24 hours post-dose after 12 weeks' treatment. Secondary biomarker endpoints included changes from baseline at Week 12 in alanine aminotransferase (ALT) and caspase-cleaved cytokeratin 18 (CK-18 caspase). Mean AOC3 activities relative to baseline at Week 12: 90.4% (placebo; n = 32), 26.5% (1 mg; n = 16), 10.4% (3 mg; n = 16), 5.0% (6 mg; n = 16), 3.3% (10 mg; n = 32). These changes indicated that BI 1467335 dose-dependently inhibited AOC3 activity; ≥3 mg doses achieved >80% inhibition ( < 20% activity) at Week 4. At Week 12 following doses of BI 1467335 ≥ 3 mg, ALT and CK-18 caspase decreased dose-dependently. All tested BI 1467335 doses were well tolerated, with no clinically relevant treatment-emergent safety signals. BI 1467335 strongly inhibited AOC3 in participants with NASH, with doses ≥3 mg dose-dependently reducing the levels of liver injury biomarkers, ALT and CK-18. This trial was registered with ClinicalTrials.gov (NCT03166735) and the European Union Drug Regulating Authorities Clinical Trials Database (EudraCT 2016-000499-83).

Impact of Helicobacter pylori-Related Metabolic Syndrome Parameters on Arterial Hypertension

Arterial hypertension is a risk factor for several pathologies, mainly including cardio-cerebrovascular diseases, which rank as leading causes of morbidity and mortality worldwide. Arterial hypertension also constitutes a fundamental component of the metabolic syndrome. Helicobacter pylori infection is one of the most common types of chronic infection globally and displays a plethora of both gastric and extragastric effects. Among other entities, Helicobacter pylori has been implicated in the pathogenesis of the metabolic syndrome. Within this review, we illustrate the current state-of-the-art evidence, which may link several components of the Helicobacter pylori-related metabolic syndrome, including non-alcoholic fatty liver disease and arterial hypertension. In particular, current knowledge of how Helicobacter pylori exerts its virulence through dietary, inflammatory and metabolic pathways will be discussed. Although there is still no causative link between these entities, the emerging evidence from both basic and clinical research supports the proposal that several components of the Helicobacter pylori infection-related metabolic syndrome present an important risk factor in the development of arterial hypertension. The triad of Helicobacter pylori infection, the metabolic syndrome, and hypertension represents a crucial worldwide health problem on a pandemic scale with high morbidity and mortality, like COVID-19, thereby requiring awareness and appropriate management on a global scale.

Clinical assessment and management of liver fibrosis in non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is among the most frequent etiologies of cirrhosis worldwide, and it is associated with features of metabolic syndrome; the key factor influencing its prognosis is the progression of liver fibrosis. This review aimed to propose a practical and stepwise approach to the evaluation and management of liver fibrosis in patients with NAFLD, analyzing the currently available literature. In the assessment of NAFLD patients, it is important to identify clinical, genetic, and environmental determinants of fibrosis development and its progression. To properly detect fibrosis, it is important to take into account the available methods and their supporting scientific evidence to guide the approach and the sequential selection of the best available biochemical scores, followed by a complementary imaging study (transient elastography, magnetic resonance elastography or acoustic radiation force impulse) and finally a liver biopsy, when needed. To help with the selection of the most appropriate method a Fagan's nomogram analysis is provided in this review, describing the diagnostic yield of each method and their post-test probability of detecting liver fibrosis. Finally, treatment should always include diet and exercise, as well as controlling the components of the metabolic syndrome, +/- vitamin E, considering the presence of sleep apnea, and when available, allocate those patients with advanced fibrosis or high risk of progression into clinical trials. The final end of this approach should be to establish an opportune diagnosis and treatment of liver fibrosis in patients with NAFLD, aiming to decrease/stop its progression and improve their prognosis.

Understanding the association of polycystic ovary syndrome and non-alcoholic fatty liver disease

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder among reproductive-age women. Patients with non-alcoholic fatty liver disease (NAFLD) often suffer from metabolic syndrome, atherosclerosis, ischemic heart disease, and extrahepatic tumors, conferring a lower survival than the general population; therefore it is crucial to study the association between NAFLD and PCOS since it remains poorly understood. Insulin resistance (IR) plays a central role in the pathogenesis of NAFLD and PCOS; also, hyperandrogenism enhances IR in these patients. IR, present in the NAFLD-PCOS association could decrease the hepatic production of sex hormone-binding globulin through a possible regulation mediated by hepatocyte nuclear factor 4 alpha. On the other hand, apoptotic processes initiated by androgens actively contribute to the progression of NAFLD. Considering the association between the two conditions, the screening of women with PCOS for the presence of NAFLD appears reasonable. The pathophysiological mechanisms of PCOS-NAFLD association and the initial approach will be reviewed here.

Selection of potential cytokeratin-18 monoclonal antibodies following IGH repertoire evaluation in mice

Cytokeratin 18 (CK18), the main scaffold protein of keratinocyte, is distributed in epithelial cells. This structural protein maintains the integrity and continuity of epithelial tissue. Cytokeratin is also frequently used as an immunohistochemical marker of tumor growth. In recent years, immune repertoire (IR) evaluation using next-generation sequencing (NGS) have become increasingly efficient. Here we deep sequenced the mouse IR of the immunoglobulin heavy chain (IGH) after CK18 immunization. We comprehensively analyzed the IR based on complementarity determining region 3 (CDR3) abundance, germline gene usage polarization, clone diversity, and lineage. We found many convergence characteristics after CK18 immunization. Convergence represents a phenomenon that antigen stimulation or pathogen exposure induces the antigen specific clone expansion and enrichment. The convergence could be used for the immune evaluation and antibody screen. After immunization, the IGHV5 gene clusters became preponderant. The abundance and length of the most frequent CDR3 both increased, nevertheless the IR diversity level decreased. From the convergent IGH repertoires, we selected and expressed six antibodies with the most frequent CDR3s and IGH V-J combinations. The ELISA results suggested all screened six antibodies bound CK18 specifically. The most potential antibody had 9.424E-10M M affinity for the interaction with the CK18. Therefore, this is the NGS platform has been first used for anti-CK18 monoclonal antibodies (MAbs) discovery. These analyses methods could also be used for vaccine evaluation.

Mitochondrial Dysfunction and Signaling in Chronic Liver Diseases

Mitochondria regulate hepatic lipid metabolism and oxidative stress. Ultrastructural mitochondrial lesions, altered mitochondrial dynamics, decreased activity of respiratory chain complexes, and impaired ability to synthesize adenosine triphosphate are observed in liver tissues from patients with alcohol-associated and non-associated liver diseases. Increased lipogenesis with decreased fatty acid β-oxidation leads to the accumulation of triglycerides in hepatocytes, which, combined with increased levels of reactive oxygen species, contributes to insulin resistance in patients with steatohepatitis. Moreover, mitochondrial reactive oxygen species mediate metabolic pathway signaling; alterations in these pathways affect development and progression of chronic liver diseases. Mitochondrial stress and lesions promote cell death, liver fibrogenesis, inflammation, and the innate immune responses to viral infections. We review the involvement of mitochondrial processes in development of chronic liver diseases, such as nonalcoholic fatty, alcohol-associated, and drug-associated liver diseases, as well as hepatitis B and C, and discuss how they might be targeted therapeutically.