Panel sequencing links rare, likely damaging gene variants with distinct clinical phenotypes and outcomes in juvenile-onset SLE

OBJECTIVES

Juvenile-onset systemic lupus erythematosus (jSLE) affects 15-20% of lupus patients. Clinical heterogeneity between racial groups, age groups and individual patients suggests variable pathophysiology. This study aimed to identify highly penetrant damaging mutations in genes associated with SLE/SLE-like disease in a large national cohort (UK JSLE Cohort Study) and compare demographic, clinical and laboratory features in patient sub-cohorts with 'genetic' SLE vs remaining SLE patients.

METHODS

Based on a sequencing panel designed in 2018, target enrichment and next-generation sequencing were performed in 348 patients to identify damaging gene variants. Findings were integrated with demographic, clinical and treatment related datasets.

RESULTS

Damaging gene variants were identified in ∼3.5% of jSLE patients. When compared with the remaining cohort, 'genetic' SLE affected younger children and more Black African/Caribbean patients. 'Genetic' SLE patients exhibited less organ involvement and damage, and neuropsychiatric involvement developed over time. Less aggressive first line treatment was chosen in 'genetic' SLE patients, but more second and third line agents were used. 'Genetic' SLE associated with anti-dsDNA antibody positivity at diagnosis and reduced ANA, anti-LA and anti-Sm antibody positivity at last visit.

CONCLUSION

Approximately 3.5% of jSLE patients present damaging gene variants associated with younger age at onset, and distinct clinical features. As less commonly observed after treatment induction, in 'genetic' SLE, autoantibody positivity may be the result of tissue damage and explain reduced immune complex-mediated renal and haematological involvement. Routine sequencing could allow for patient stratification, risk assessment and target-directed treatment, thereby increasing efficacy and reducing toxicity.

Research priority setting for paediatric rheumatology in the UK

The evidence base that underlies the management of children and young people with paediatric rheumatic diseases is deficient. In this field, there are many crucial unanswered questions. The UK Paediatric Rheumatology Clinical Studies Group, supported by UK National Institute for Health Research Clinical Research Network: children and Versus Arthritis, elicited ideas for research priorities from paediatric rheumatologists, trainees, allied health-care professionals, nurse specialists, patients, parents of patients, carers, and charities. These ideas were collected through online surveys and face-to-face meetings. A modified Delphi process was used, which included online research priority ranking surveys and a consensus workshop. A longlist of 55 disease-specific research priorities and 37 general research priorities were voted on in the first survey. A list of 11 top general research priorities was produced. The top ten disease-specific research priorities were discussed in depth at a Delphi workshop to determine their final ranking. This Health Policy paper will help to guide clinicians, academics, and funding bodies to prioritise research in paediatric rheumatic diseases, specifically in areas of unmet patient needs.

Real world treatment of juvenile-onset systemic lupus erythematosus: Data from the UK JSLE cohort study

BACKGROUND

In the absence of clinical trials evidence, Juvenile-onset Systemic Lupus Erythematosus (JSLE) treatment plans vary.

AIM

To explore 'real world' treatment utilising longitudinal UK JSLE Cohort Study data.

METHODS

Data collected between 07/2009-05/2020 was used to explore the choice/sequence of immunomodulating drugs from diagnosis. Multivariate logistic regression determined how organ-domain involvement (pBILAG-2004) impacted treatment choice.

RESULT

349 patients met inclusion criteria, median follow-up 4-years (IQR:2,6). Mycophenolate mofetil (MMF) was most commonly used for the majority of organ-domains, and significantly associated with renal involvement (OR:1.99, 95% CI:1.65-2.41, pc < 0.01). Analyses assessing the sequence of immunomodulators focused on 197/349 patients (meeting relevant inclusion/exclusion criteria). 10/197 (5%) solely recieved hydroxychloroquine/prednisolone, 62/197 (31%) received a single-immunomodulator, 69/197 (36%) received two, and 36/197 patients (28%) received ≥three immunomodulators. The most common first and second line immunomodulator was MMF. Rituximab was the most common third-line immunomodulator.

CONCLUSIONS

Most UK JSLE patients required ≥two immunomodulators, with MMF used most commonly.

OA32 UK Paediatric Rheumatology Clinical Studies Group research priorities - results of a multidisciplinary consultation and consensus exercise

Background/Aims

The evidence base underlying the management of children and young people (CYP) with paediatric rheumatic diseases (PRDs) is inadequate, with many critical outstanding questions warranting investigation. The aim of this study was to elicit multidisciplinary PRDs research priorities, through consultation with patients, carers and healthcare professionals.

Methods

This study was led by the UK NIHR CRN Children/Versus Arthritis Paediatric Rheumatology CSG (referred to as ‘the CSG’) and its Topic Specific Groups (TSGs). The CSG is a multidisciplinary group with strong patient/parent representation, supporting the development of clinical studies in the UK. Research priority ideas were sought from paediatric rheumatologists, trainees, allied healthcare professional (AHP), nurses, patients, parents and charities, through online surveys and face-to-face meetings. Research ideas were categorised as disease-specific or broad/general. They were grouped into sub-themes, duplicates/questions that had already been answered were removed, and similar submissions combined. A modified Delphi process was undertaken, including online research priority ranking, and an online consensus workshop to derive top PRD research priorities.

Results

The initial consultation yielded 304 research priority ideas; 25% from patients/parents, 22% from the CSG, 18% from TSGs, 13% from AHPs, 11% from trainees, 11% from Nurses. 55 disease-specific and 37 broad/general research priorities were voted upon in the first online survey, yielding a top 11 general broad research priorities. The top 10 disease specific priorities were discussed at the online Delphi priority setting workshop, and two online surveys were held during the workshop to determine their final ranking. Two of the disease-specific priorities were combined, leading to a top 9 (see Table). Disease specific proprieties related to clinical trials in JIA (n = 3) / Juvenile Dermatomyositis (n = 1) / Chronic Recurrent Multifocal Osteomyelitis (n = 1) / Juvenile Systemic Lupus Erythematosus (n = 1) Scleroderma (n = 1), management of JIA in adulthood (n = 1) and chronic pain (n = 1).

Conclusion

UK consensus-based PRD research priorities have been derived, underpinned by collaboration with patients/carers and healthcare professionals, helping to guide funding bodies to improve the evidence base in PRD’s.

Disclosure

E.M.D. Smith: None. N. Egbivwie: None. K. Cowan: None. A.V. Ramanan: None. C.E. Pain: None.

FGFR1 Expression and Role in Migration in Low and High Grade Pediatric Gliomas

The heterogeneous and invasive nature of pediatric gliomas poses significant treatment challenges, highlighting the importance of identifying novel chemotherapeutic targets. Recently, recurrent Fibroblast growth factor receptor 1 (FGFR1) mutations in pediatric gliomas have been reported. Here, we explored the clinical relevance of FGFR1 expression, cell migration in low and high grade pediatric gliomas and the role of FGFR1 in cell migration/invasion as a potential chemotherapeutic target. A high density tissue microarray (TMA) was used to investigate associations between FGFR1 and activated phosphorylated FGFR1 (pFGFR1) expression and various clinicopathologic parameters. Expression of FGFR1 and pFGFR1 were measured by immunofluorescence and by immunohistochemistry (IHC) in 3D spheroids in five rare patient-derived pediatric low-grade glioma (pLGG) and two established high-grade glioma (pHGG) cell lines. Two-dimensional (2D) and three-dimensional (3D) migration assays were performed for migration and inhibitor studies with three FGFR1 inhibitors. High FGFR1 expression was associated with age, malignancy, tumor location and tumor grade among astrocytomas. Membranous pFGFR1 was associated with malignancy and tumor grade. All glioma cell lines exhibited varying levels of FGFR1 and pFGFR1 expression and migratory phenotypes. There were significant anti-migratory effects on the pHGG cell lines with inhibitor treatment and anti-migratory or pro-migratory responses to FGFR1 inhibition in the pLGGs. Our findings support further research to target FGFR1 signaling in pediatric gliomas.