Germinal Center B Cells Regulate Their Capability to Present Antigen by Modulation of HLA-DO

Peptide acquisition by MHC class II molecules is catalyzed by HLA-DM (DM). In B cells, HLA-DO (DO) inhibits or modifies the peptide exchange activity of DM. We show here that DO protein levels are modulated during B cell differentiation. Remarkably, germinal center (GC) B cells, which have low levels of DO relative to naive and memory B cells, are shown to have enhanced antigen presentation capabilities. DM protein levels also were somewhat reduced in GC B cells; however, the ratio of DM to DO in GC B cells was substantially increased, resulting in more free DM in GC B cells. We conclude that modulation of DM and DO in distinct stages of B cell differentiation represents a mechanism by which B cells regulate their capacity to function as antigen-presenting cells. Efficient antigen presentation in GC B cells would promote GC B cell–T cell interactions that are essential for B cells to survive positive selection in the GC

Green plants in the red : a baseline global assessment for the IUCN Sampled Red List Index for Plants

Plants provide fundamental support systems for life on Earth and are the basis for all terrestrial ecosystems; a decline in plant diversity will be detrimental to all other groups of organisms including humans. Decline in plant diversity has been hard to quantify, due to the huge numbers of known and yet to be discovered species and the lack of an adequate baseline assessment of extinction risk against which to track changes. The biodiversity of many remote parts of the world remains poorly known, and the rate of new assessments of extinction risk for individual plant species approximates the rate at which new plant species are described. Thus the question 'How threatened are plants?' is still very difficult to answer accurately. While completing assessments for each species of plant remains a distant prospect, by assessing a randomly selected sample of species the Sampled Red List Index for Plants gives, for the first time, an accurate view of how threatened plants are across the world. It represents the first key phase of ongoing efforts to monitor the status of the world's plants. More than 20% of plant species assessed are threatened with extinction, and the habitat with the most threatened species is overwhelmingly tropical rain forest, where the greatest threat to plants is anthropogenic habitat conversion, for arable and livestock agriculture, and harvesting of natural resources. Gymnosperms (e.g. conifers and cycads) are the most threatened group, while a third of plant species included in this study have yet to receive an assessment or are so poorly known that we cannot yet ascertain whether they are threatened or not. This study provides a baseline assessment from which trends in the status of plant biodiversity can be measured and periodically reassessed.Publisher PDFPeer reviewe

Results of a pilot feasibility randomised controlled trial exploring the use of an electronic patient-reported outcome measure in the management of UK patients with advanced chronic kidney disease.

OBJECTIVES The use of routine remote follow-up of patients with chronic kidney disease (CKD) is increasing exponentially. It has been suggested that online electronic patient-reported outcome measures (ePROMs) could be used in parallel, to facilitate real-time symptom monitoring aimed at improving outcomes. We tested the feasibility of this approach in a pilot trial of ePROM symptom monitoring versus usual care in patients with advanced CKD not on dialysis. DESIGN A 12-month, parallel, pilot randomised controlled trial (RCT) and qualitative substudy. SETTING AND PARTICIPANTS Queen Elizabeth Hospital Birmingham, UK. Adult patients with advanced CKD (estimated glomerular filtration rate ≥6 and ≤15 mL/min/1.73 m, or a projected risk of progression to kidney failure within 2 years ≥20%). INTERVENTION Monthly online ePROM symptom reporting, including automated feedback of tailored self-management advice and triggered clinical notifications in the advent of severe symptoms. Real-time ePROM data were made available to the clinical team via the electronic medical record. OUTCOMES Feasibility (recruitment and retention rates, and acceptability/adherence to the ePROM intervention). Health-related quality of life, clinical data (eg, measures of kidney function, kidney failure, hospitalisation, death) and healthcare utilisation. RESULTS 52 patients were randomised (31% of approached). Case report form returns were high (99.5%), as was retention (96%). Overall, 73% of expected ePROM questionnaires were received. Intervention adherence was high beyond 90 days (74%) and 180 days (65%); but dropped beyond 270 days (46%). Qualitative interviews supported proof of concept and intervention acceptability, but highlighted necessary changes aimed at enhancing overall functionality/scalability of the ePROM system. LIMITATIONS Small sample size. CONCLUSIONS This pilot trial demonstrates that patients are willing to be randomised to a trial assessing ePROM symptom monitoring. The intervention was considered acceptable; though measures to improve longer-term engagement are needed. A full-scale RCT is considered feasible. TRIAL REGISTRATION NUMBER ISRCTN12669006 and the UK NIHR Portfolio (CPMS ID: 36497)

Development of an electronic patient-reported outcome measure (ePROM) system to aid the management of patients with advanced chronic kidney disease.

BACKGROUND Effective management of patients with chronic kidney disease (CKD) relies on timely detection of clinical deterioration towards end stage kidney failure. We aimed to design an electronic Patient-Reported Outcome Measure (ePROM) system, which would allow patients with advanced CKD (pre-dialysis) to: (i) remotely self-report their symptoms using a simple and secure online platform; (ii) share the data with the clinical team in real-time via the electronic patient record to help optimise care. We adopted a staged development process which included: a systematic review of PROMs used in CKD; formation of a co-design team; prototype system design/development, user acceptance testing and refinement; finalisation of the system for testing in a pilot/feasibility trial. RESULTS A co-design team was convened, including patients with lived experience of CKD; clinical team members; IT/Informatics experts; academics; and Birmingham Clinical Trials Unit representatives. A prototype system was developed and iterative changes made before finalisation during a series of operational meetings. The system allows patients to remotely self-report their symptoms; provides tailored self-management advice; allows monitoring of real-time patient ePROM data; sends automated notifications to the patient/clinical team in the advent of a severe symptom report; and incorporates longitudinal ePROM symptom data into the electronic patient record. Feasibility of the system will be evaluated as part of the National Institute for Health Research funded RePROM (Renal electronic Patient-Reported Outcome Measure) pilot trial (ISRCTN12669006). CONCLUSIONS Routine ePROM collection with real-time feedback has the potential to improve outcomes and reduce health service costs. We have successfully developed a trial-ready ePROM system for advanced CKD, the feasibility of which is currently being explored in a pilot trial. Assuming feasibility is demonstrated, formal evaluation of efficacy will take place in a future multi-centre randomised controlled trial

Plasma Markers of B-Cell Activation and Clonality in Pediatric Liver and Hematopoietic Stem Cell Transplant Recipients

INTRODUCTION: Transplant recipients are at risk of post-transplant lymphoproliferative disease (PTLD). Methods: Thirty-six pediatric transplant recipients were evaluated (18 hematopoietic stem cell and 18 liver recipients; 12 had PTLD). We studied 207 longitudinal plasma samples from these recipients for three markers of B-cell activation or clonality: immunoglobulin free light chains (FLCs), soluble CD30 (sCD30), and monoclonal immunoglobulins (M-proteins). RESULTS: Kappa FLCs, lambda FLCs, and sCD30 were elevated in 20.8%, 28.0%, and 94.2% of plasma specimens, respectively. FLC and sCD30 levels increased significantly 1.18–1.82 fold per log(10) Epstein Barr virus (EBV) load in peripheral blood. Five PTLD cases manifested elevated FLCs with an abnormal kappa/lambda ratio, suggesting monoclonal FLC production. M-proteins were present in 91% of PTLD cases, vs. 50–67% of other recipients with high or low EBV loads (p=0.13). Concordance of FLCs, M-proteins, and PTLD tumor light chain restriction was imperfect. For example, one PTLD case with an IgG lambda M-protein had a tumor that was kappa restricted, and another case with an M-protein had a T-cell PTLD. In an additional case, an IgM kappa M-protein and excess kappa FLCs were both detected in plasma at PTLD diagnosis; while the tumor was not restricted at diagnosis, kappa restriction was present 5 years later when the PTLD relapsed. DISCUSSION: Plasma markers of B-cell dysfunction are frequent following transplantation and associated with poor EBV control. These abnormal markers may be produced by oligoclonal B-cell populations or PTLD tumor cells, and could potentially help identify recipients at high risk of PTLD

International, evidence-based consensus treatment guidelines for idiopathic multicentric Castleman disease

Castleman disease (CD) describes a group of heterogeneous hematologic disorders with characteristic histopathological features. CD can present with unicentric or multicentric (MCD) regions of lymph node enlargement. Some cases of MCD are caused by human herpesvirus-8 (HHV-8), whereas others are HHV-8-negative/idiopathic (iMCD). Treatment of iMCD is challenging, and outcomes can be poor because no uniform treatment guidelines exist, few systematic studies have been conducted, and no agreed upon response criteria have been described. The purpose of this paper is to establish consensus, evidence-based treatment guidelines based on the severity of iMCD to improve outcomes. An international Working Group of 42 experts from 10 countries was convened by the Castleman Disease Collaborative Network to establish consensus guidelines for the management of iMCD based on published literature, review of treatment effectiveness for 344 cases, and expert opinion. The anti-interleukin-6 monoclonal antibody siltuximab (or tocilizumab, if siltuximab is not available) with or without corticosteroids is the preferred first-line therapy for iMCD. In the most severe cases, adjuvant combination chemotherapy is recommended. Additional agents are recommended, tailored by disease severity, as second- and third-line therapies for treatment failures. Response criteria were formulated to facilitate the evaluation of treatment failure or success. These guidelines should help treating physicians to stratify patients based on disease severity in order to select the best available therapeutic option. An international registry for patients with CD (ACCELERATE, #NCT02817997) was established in October 2016 to collect patient outcomes to increase the evidence base for selection of therapies in the future