Are Clinicians Ready for Safe Use of Stratified Therapy in Primary Biliary Cholangitis (PBC)? A Study of Educational Awareness

Research experimental design for the construction and identification of the pGEX-BCKD-E4A recombinant point-mutant plasmid

Primary biliary cirrhosis (PBC) is an organ-specific autoimmune disease that eventually develops into cirrhosis and even liver cancer. In recent years, the incidence rate has been increasing, and the early diagnosis and treatment of PBC are crucial. In the early diagnosis method of PBC, anti-mitochondrial antibodies (AMAs) are an important diagnostic basis, especially the M2 subtype (AMA-M2) with almost 100% specificity. We selected the BCOADC-E2 protein, a mitochondrial autoantigen that reacts specifically with AMA-M2 antibodies, and carried out DNA recombination and protein mutation experiments by cloning in vitro the homologous target gene sequence BCKD that expresses the antigenic epitope of BCOADC-E2 protein, to provide experience for later exploring the effect of mutations of amino acids around the lysine in the active center of BCOADC-E2 protein on its specific binding to AMA-M2, and to lay the foundation for determining the key amino acids of BCOADC-E2 for the diagnosis and treatment of PBC. In addition, we apply this scientific research content to graduate course teaching. Experimental technology of microbial molecular ecology is a course with the cross-integration of multidisciplinary knowledge and experimental skills offered at our college since 2018. This article derives from the part of this course on the construction of recombinant plasmids. The students first constructed the recombinant plasmid pGEX-BCKD using the vector plasmid pGEX-4T1 and the target gene fragment BCKD provided by the laboratory and used this as a template to construct the pGEX-BCKD-E4A point mutation plasmid by the overlap extension PCR (SOE PCR) technique to achieve the effect of mutating the fifth amino acid glutamate in front of lysine, the active centre of the BCOADC-E2 lipid acyl binding domain, to alanine for subsequent studies. Through the research experiment, combining theoretical knowledge and experimental operation, we aim to deepen the student's understanding of DNA recombination technology, let them feel the practical application prospect of experimental technology, stimulate students' interest in professional knowledge learning, and cultivate students' scientific thinking and innovation consciousness. We examined the quality of the teaching through the process and summative evaluation of the students. In this study, the students successfully completed the construction of pGEX-BCKD-E4A point mutant plasmid, and the average test score increased from 40.4% before teaching to 91.1%. The teaching effect was remarkable. This kind of research experimental teaching mode has good application prospects, and other education and teachers can refer to and reference it.

The relationship between disease activity and UDCA response criteria in primary biliary cholangitis: A cohort study

BACKGROUND

Uncertainty exists about how best to identify primary biliary cholangitis (PBC) patients who would benefit from second-line therapy. Existing, purely clinical, ursodeoxycholic acid (UDCA) response criteria accept degrees of liver biochemistry abnormality in responding patients, emerging data, however, suggest that any degree of ongoing abnormality may, in fact, be associated with an increased risk of adverse outcomes. This cohort study explores the link between response status, the biology of high-risk disease and its implications for clinical practice.

METHODS

Proteomics, exploring 19 markers previously identified as remaining elevated in PBC following UDCA therapy, were performed on 400 serum samples, from participants previously recruited to the UK-PBC Nested Cohort between 2014 and 2019. All participants had an established diagnosis of PBC and were taking therapeutic doses of UDCA for greater than 12 months. UDCA response status was assessed using Paris 1, Paris 2 and the POISE criteria, with additional analyses using normal liver blood tests stratified by bilirubin level. Statistical analysis using parametric t tests and 1-way ANOVA.

FINDINGS

Disease markers were statistically significantly higher in UDCA non-responders than in responders for all the UDCA response criteria, suggesting a meaningful link between biochemical disease status and disease mechanism. For each of the criteria, however, marker levels were also statistically significantly higher in responders with ongoing liver function test abnormality compared to those who had normalised their liver biochemistry. IL-4RA, IL-18-R1, CXCL11, 9 and 10, CD163 and ACE2 were consistently elevated across all responder groups with ongoing LFT abnormality. No statistically significant differences occurred between markers in normal LFT groups stratified by bilirubin level.

INTERPRETATION

This study provides evidence that any ongoing elevation in alkaline phosphatase levels in PBC after UDCA therapy is associated with some degree of ongoing disease activity. There was no difference in activity between patients with normal LFT when stratified by bilirubin. These findings suggest that if our goal is to completely control disease activity in PBC, then normalisation of alkaline phosphatase and bilirubin should be the treatment target. This would also simplify messaging around goals of therapy in PBC, benefiting both patients and clinicians.

FUNDING

Funding by the UK Medical Research Council (Stratified Medicine Programme) and an independent research grant by Pfizer. The study funders played no role in the study design, data collection, data analyses, data interpretation or manuscript writing.

Patient ownership of primary biliary cholangitis long-term management

OBJECTIVE

Patient ownership of disease is vital in rare diseases like primary biliary cholangitis (PBC). This survey of UK members of the PBC foundation aimed to assess patients' perception of their disease management, focusing on key biomarkers and problematic symptoms.

DESIGN

Registered PBC foundation members were surveyed on their experiences on their most recent clinic visit, covering the type of hospital and clinician and whether biochemical response and symptom burden were discussed, including who initiated these conversations. Respondents were also asked about their willingness to initiate these conversations.

RESULTS

Across 633 respondents, 42% remembered discussing alkaline phosphatase, the key biochemical response measure, and the majority of discussions were initiated by the healthcare provider. 56% of respondents remembered discussing itch, a key PBC symptom. There was no distinction between the grade of healthcare professional, but both patients and clinicians were significantly more likely to discuss symptoms over disease progression. Reassuringly, 84% of respondents felt willing to initiate conversations about their illness, regardless of the grade of managing clinician.

CONCLUSIONS

This work lays a positive foundation for patient education and empowerment projects, likely to improve clinical outcomes. Key aspects of management (biochemical response to treatment and symptom burden) should be emphasised as topics of discussion to both patients and clinicians managing PBC. We suggest a simple cue card to prompt patient-led discussion.

Pruritus Is Common and Undertreated in Patients With Primary Biliary Cholangitis in the United Kingdom

BACKGROUND AND AIMS

Little is known about the prevalence or treatment of pruritus associated with primary biliary cholangitis (PBC). We analyzed data from patients with PBC recruited from all clinical centers in the United Kingdom (UK) to characterize the prevalence, severity, progression, and treatment of pruritus.

METHODS

We performed cross-sectional and longitudinal studies of patients in the UK-PBC cohort to assess trajectories of pruritus. Data on pruritus frequency, severity, and therapy were collected via paper questionnaires completed by 2194 patients at their initial assessment in 2011 and then again in 2014 and 2017. Self-reported treatment data were validated against the prescription record of PBC cohort in the Clinical Practice Research Datalink, a primary care database. We defined persistent pruritus as itch that occurs frequently or all the time and severe pruritus as PBC-40 pruritus domain scores of 12 or more, throughout their disease course. Latent class mixed models were used to study pruritus trajectories and identify factors associated with high pruritus.

RESULTS

At initial assessment, 1613 (73.5%) patients had experienced pruritus at some point since their development of PBC-persistent pruritus was reported by 34.5% of the patients and severe pruritus by 11.7%. Only 37.4% of patients with persistent pruritus and 50% with severe pruritus reported ever receiving cholestyramine. Frequencies of rifampicin use were 11% in patients with persistent pruritus and 23% in patients with severe pruritus. Comparison of 2011 and 2014 surveys (comprising 1423 patients) showed consistent self-reported data on pruritus. Proportions of patients in the UK-PBC cohort treated with cholestyramine or naltrexone (37.4% and 4.4%) did not differ significantly from proportions treated in the Clinical Practice Research Datalink cohort (30.4% and 4.4%) (P = .07 for cholestyramine and P = .32 for naltrexone). Latent class mixed models (n = 1753) identified 3 different groups of pruritus. Multivariable analysis identified younger age at diagnosis and higher level of alkaline phosphatase at 12 months after diagnosis as factors significantly associated with persistent high pruritus.

CONCLUSIONS

In a large national cohort study of patients with PBC, we found a high prevalence of pruritus and inadequate guideline-recommended therapy. Patient-reported data used to determine pruritus prevalence and treatment are reliable. Younger age and levels of higher alkaline phosphatase were associated with persistent pruritus. We need to increase awareness and management of pruritus in PBC in the UK.