Single-cell insights into immune dysregulation in rheumatoid arthritis flare versus drug-free remission

Immune-mediated inflammatory diseases (IMIDs) are typically characterised by relapsing and remitting flares of inflammation. However, the unpredictability of disease flares impedes their study. Addressing this critical knowledge gap, we use the experimental medicine approach of immunomodulatory drug withdrawal in rheumatoid arthritis (RA) remission to synchronise flare processes allowing detailed characterisation. Exploratory mass cytometry analyses reveal three circulating cellular subsets heralding the onset of arthritis flare - CD45RO+PD1hi CD4+ and CD8+ T cells, and CD27+CD86+CD21- B cells - further characterised by single-cell sequencing. Distinct lymphocyte subsets including cytotoxic and exhausted CD4+ memory T cells, memory CD8+CXCR5+ T cells, and IGHA1+ plasma cells are primed for activation in flare patients. Regulatory memory CD4+ T cells (Treg cells) increase at flare onset, but with dysfunctional regulatory marker expression compared to drug-free remission. Significant clonal expansion is observed in T cells, but not B cells, after drug cessation; this is widespread throughout memory CD8+ T cell subsets but limited to the granzyme-expressing cytotoxic subset within CD4+ memory T cells. Based on our observations, we suggest a model of immune dysregulation for understanding RA flare, with potential for further translational research towards novel avenues for its treatment and prevention.

Number of days required to measure sedentary time and physical activity using accelerometery in rheumatoid arthritis: a reliability study

This study aimed to determine the minimum number of days required to reliably estimate free-living sedentary time, light-intensity physical activity (LPA) and moderate-intensity physical activity (MPA) using accelerometer data in people with Rheumatoid Arthritis (RA), according to Disease Activity Score-28-C-reactive protein (DAS-28-CRP). Secondary analysis of two existing RA cohorts with controlled (cohort 1) and active (cohort 2) disease was undertaken. People with RA were classified as being in remission (DAS-28-CRP < 2.4, n = 9), or with low (DAS-28-CRP ≥ 2.4-≤ 3.2, n = 15), moderate (DAS-28-CRP > 3.2-≤ 5.1, n = 41) or high (DAS-28-CRP > 5.1, n = 16) disease activity. Participants wore an ActiGraph accelerometer on their right hip for 7 days during waking hours. Validated RA-specific cut-points were applied to accelerometer data to estimate free-living sedentary time, LPA and MPA (%/day). Single-day intraclass correlation coefficients (ICC) were calculated and used in the Spearman Brown prophecy formula to determine the number of monitoring days required to achieve measurement reliability (ICC ≥ 0.80) for each group. The remission group required ≥ 4 monitoring days to achieve an ICC ≥ 0.80 for sedentary time and LPA, with low, moderate and high disease activity groups requiring ≥ 3 monitoring days to reliably estimate these behaviours. The monitoring days required for MPA were more variable across disease activity groups (remission =  ≥ 3 days; low =  ≥ 2 days; moderate =  ≥ 3 days; high =  ≥ 5 days). We conclude at least 4 monitoring days will reliably estimate sedentary time and LPA in RA, across the whole spectrum of disease activity. However, to reliably estimate behaviours across the movement continuum (sedentary time, LPA, MPA), at least 5 monitoring days are required.

Clinical frailty, and not features of acute infection, is associated with late mortality in COVID-19: a retrospective cohort study

BACKGROUND

Coronavirus disease 2019 (COVID-19) is associated with excess mortality after hospital discharge. Identification of patients at increased risk of death following hospital discharge is needed to guide clinical monitoring and early intervention. Herein, we aimed to identify predictors of early vs. late mortality in COVID-19 patients.

METHODS

A total of 471 patients with polymerase chain reaction-confirmed COVID-19 were followed up for 9 months [median (inter-quartile range) of follow-up time: 271 (14) days] after hospital admission. COVID-19-related signs and symptoms, laboratory features, co-morbidities, Coronavirus Clinical Characterisation Consortium (4C) mortality and Clinical Frailty Scale (CFS) scores were analysed by logistic regression for association with early (28 day) vs. late mortality. Receiver operating characteristic (ROC) analysis was used to determine the discriminative value of 4C and CFS scores for early vs. late mortality.

RESULTS

A total of 120 patients died within 28 days from hospital admission. Of the remaining 351 patients, 41 died within the next 8 months. Respiratory failure, systemic inflammation, and renal impairment were associated with early mortality, while active cancer and dementia were associated with late mortality, after adjustment for age and sex. 4C mortality score and CFS were associated with both early [odds ratio (OR) (95% confidence interval-CI): 4C: 1.34 (1.25-1.45); CFS: 1.49 (1.33-1.66)] and late [OR (95% CI): 4C: 1.23 (1.12-1.36); CFS: 2.04 (1.62-2.56)] mortality. After adjustment for CFS, the association between 4C and late mortality was lost. By ROC analysis, 4C mortality score was superior to CFS for 28 day mortality [area under the curve (AUC) (95% CI): 0.779 (0.732-0.825) vs. 0.723 (0.673-0.773), respectively; P = 0.039]. In contrast, CFS had higher predictive value for late mortality compared with 4C mortality score [AUC (95% CI): 0.830 (0.776-0.883) vs. 0.724 (0.650-0.798), respectively; P = 0.007].

CONCLUSIONS

In our cohort, late mortality in COVID-19 patients is more strongly associated with premorbid clinical frailty than with severity of the acute infection phase.

Estimated pulse wave velocity improves risk stratification for all-cause mortality in patients with COVID-19

Accurate risk stratification in COVID-19 patients consists a major clinical need to guide therapeutic strategies. We sought to evaluate the prognostic role of estimated pulse wave velocity (ePWV), a marker of arterial stiffness which reflects overall arterial integrity and aging, in risk stratification of hospitalized patients with COVID-19. This retrospective, longitudinal cohort study, analyzed a total population of 1671 subjects consisting of 737 hospitalized COVID-19 patients consecutively recruited from two tertiary centers (Newcastle cohort: n = 471 and Pisa cohort: n = 266) and a non-COVID control cohort (n = 934). Arterial stiffness was calculated using validated formulae for ePWV. ePWV progressively increased across the control group, COVID-19 survivors and deceased patients (adjusted mean increase per group 1.89 m/s, P < 0.001). Using a machine learning approach, ePWV provided incremental prognostic value and improved reclassification for mortality over the core model including age, sex and comorbidities [AUC (core model + ePWV vs. core model) = 0.864 vs. 0.755]. ePWV provided similar prognostic value when pulse pressure or hs-Troponin were added to the core model or over its components including age and mean blood pressure (p < 0.05 for all). The optimal prognostic ePWV value was 13.0 m/s. ePWV conferred additive discrimination (AUC: 0.817 versus 0.779, P < 0.001) and reclassification value (NRI = 0.381, P < 0.001) over the 4C Mortality score, a validated score for predicting mortality in COVID-19 and the Charlson comorbidity index. We suggest that calculation of ePWV, a readily applicable estimation of arterial stiffness, may serve as an additional clinical tool to refine risk stratification of hospitalized patients with COVID-19 beyond established risk factors and scores.

Evaluation of procalcitonin-guided antimicrobial stewardship in patients admitted to hospital with COVID-19 pneumonia

Background

Procalcitonin is a biomarker that may be able to identify patients with COVID-19 pneumonia who do not require antimicrobials for bacterial respiratory tract co-infections.

Objectives

To evaluate the safety and effectiveness of a procalcitonin-guided algorithm in rationalizing empirical antimicrobial prescriptions in non-critically ill patients with COVID-19 pneumonia.

Methods

Retrospective, single-site, cohort study in adults hospitalized with confirmed or suspected COVID-19 pneumonia and receiving empirical antimicrobials for potential bacterial respiratory tract co-infection. Regression models were used to compare the following outcomes in patients with and without procalcitonin testing within 72 h of starting antimicrobials: antimicrobial consumption (DDD); antimicrobial duration; a composite safety outcome of death, admission to HDU/ICU or readmission to hospital within 30 days; and length of admission. Procalcitonin levels of ≤0.25 ng/L were interpreted as negatively predictive of bacterial co-infection. Effects were expressed as ratios of means (ROM) or prevalence ratios (PR) accordingly.

Results

259 patients were included in the final analysis. Antimicrobial use was lower in patients who had procalcitonin measured within 72 h of starting antimicrobials: mean antimicrobial duration 4.4 versus 5.4 days, adjusted ROM 0.7 (95% CI 0.6-0.9); mean antimicrobial consumption 6.8 versus 8.4 DDD, adjusted ROM 0.7 (95% CI 0.6-0.8). Both groups had similar composite safety outcomes (adjusted PR 0.9; 95% CI 0.6-1.3) and lengths of admission (adjusted ROM 1.3; 95% CI 0.9-1.6).

Conclusions

A procalcitonin-guided algorithm may allow for the safe reduction of antimicrobial usage in hospitalized non-critically ill patients with COVID-19 pneumonia.

BIOlogical Factors that Limit sustAined Remission in rhEumatoid arthritis (the BIO-FLARE study): protocol for a non-randomised longitudinal cohort study

BACKGROUND

Our knowledge of immune-mediated inflammatory disease (IMID) aetiology and pathogenesis has improved greatly over recent years, however, very little is known of the factors that trigger disease relapses (flares), converting diseases from inactive to active states. Focussing on rheumatoid arthritis (RA), the challenge that we will address is why IMIDs remit and relapse. Extrapolating from pathogenetic factors involved in disease initiation, new episodes of inflammation could be triggered by recurrent systemic immune dysregulation or locally by factors within the joint, either of which could be endorsed by overarching epigenetic factors or changes in systemic or localised metabolism.

METHODS

The BIO-FLARE study is a non-randomised longitudinal cohort study that aims to enrol 150 patients with RA in remission on a stable dose of non-biologic disease-modifying anti-rheumatic drugs (DMARDs), who consent to discontinue treatment. Participants stop their DMARDs at time 0 and are offered an optional ultrasound-guided synovial biopsy. They are studied intensively, with blood sampling and clinical evaluation at weeks 0, 2, 5, 8, 12 and 24. It is anticipated that 50% of participants will have a disease flare, whilst 50% remain in drug-free remission for the study duration (24 weeks). Flaring participants undergo an ultrasound-guided synovial biopsy before reinstatement of previous treatment. Blood samples will be used to investigate immune cell subsets, their activation status and their cytokine profile, autoantibody profiles and epigenetic profiles. Synovial biopsies will be examined to profile cell lineages and subtypes present at flare. Blood, urine and synovium will be examined to determine metabolic profiles. Taking into account all generated data, multivariate statistical techniques will be employed to develop a model to predict impending flare in RA, highlighting therapeutic pathways and informative biomarkers. Despite initial recruitment to time and target, the SARS-CoV-2 pandemic has impacted significantly, and a decision was taken to close recruitment at 118 participants with complete data.

DISCUSSION

This study aims to investigate the pathogenesis of flare in rheumatoid arthritis, which is a significant knowledge gap in our understanding, addressing a major unmet patient need.

TRIAL REGISTRATION

The study was retrospectively registered on 27/06/2019 in the ISRCTN registry 16371380 .

Single-cell multi-omics analysis of the immune response in COVID-19

Analysis of human blood immune cells provides insights into the coordinated response to viral infections such as severe acute respiratory syndrome coronavirus 2, which causes coronavirus disease 2019 (COVID-19). We performed single-cell transcriptome, surface proteome and T and B lymphocyte antigen receptor analyses of over 780,000 peripheral blood mononuclear cells from a cross-sectional cohort of 130 patients with varying severities of COVID-19. We identified expansion of nonclassical monocytes expressing complement transcripts (CD16+C1QA/B/C+) that sequester platelets and were predicted to replenish the alveolar macrophage pool in COVID-19. Early, uncommitted CD34+ hematopoietic stem/progenitor cells were primed toward megakaryopoiesis, accompanied by expanded megakaryocyte-committed progenitors and increased platelet activation. Clonally expanded CD8+ T cells and an increased ratio of CD8+ effector T cells to effector memory T cells characterized severe disease, while circulating follicular helper T cells accompanied mild disease. We observed a relative loss of IgA2 in symptomatic disease despite an overall expansion of plasmablasts and plasma cells. Our study highlights the coordinated immune response that contributes to COVID-19 pathogenesis and reveals discrete cellular components that can be targeted for therapy.

Biomarkers of tolerance in immune-mediated inflammatory diseases: a new era in clinical management?

Modern therapeutic agents and treatment regimens have made sustained remission an attainable target for many patients across a spectrum of immune-mediated inflammatory diseases, albeit at the risk of adverse events and the expense of drug prescription and safety monitoring. Clinicians and patients are thus increasingly faced with a novel treatment dilemma: whether and how best to stop immunomodulatory treatment in patients who achieve remission. In this final paper in a Series on therapeutic tolerance induction, we summarise our current knowledge of biomarkers of immune homeostasis in immune-mediated inflammatory diseases and their application to the prediction and attainment of sustained drug-free remission. We summarise evidence from prospective studies of immunomodulatory drug cessation across a range of immune-mediated inflammatory diseases, including rheumatoid arthritis, juvenile idiopathic arthritis, and inflammatory bowel disease. We also consider current evidence for clinical, serological, proteomic, metabolomic, cellular, and microbiomic biomarkers of immune homeostasis. Finally, we discuss the steps necessary for clinical translation of these biomarkers, as well as the potential transformative effect of these biomarkers on management of patients with immune-mediated inflammatory diseases if clinical translation is successfully achieved.

SARS-CoV-2 Testing of 11,884 Healthcare Workers at an Acute NHS Hospital Trust in England: A Retrospective Analysis

Healthcare workers (HCWs) are known to be at increased risk of infection with SARS-CoV-2, although whether these risks are equal across all roles is uncertain. Here we report a retrospective analysis of a large real-world dataset obtained from 10 March to 6 July 2020 in an NHS Foundation Trust in England with 17,126 employees. 3,338 HCWs underwent symptomatic PCR testing (14.4% positive, 2.8% of all staff) and 11,103 HCWs underwent serological testing for SARS-CoV-2 IgG (8.4% positive, 5.5% of all staff). Seropositivity was lower than other hospital settings in England but higher than community estimates. Increased test positivity rates were observed in HCWs from BAME backgrounds and residents in areas of higher social deprivation. A multiple logistic regression model adjusting for ethnicity and social deprivation confirmed statistically significant increases in the odds of testing positive in certain occupational groups, most notably domestic services staff, nurses, and health-care assistants. PCR testing of symptomatic HCWs appeared to underestimate overall infection levels, probably due to asymptomatic seroconversion. Clinical outcomes were reassuring, with only a small minority of HCWs with COVID-19 requiring hospitalization (2.3%) or ICU management (0.7%) and with no deaths. Despite a relatively low level of HCW infection compared to other UK cohorts, there were nevertheless important differences in test positivity rates between occupational groups, robust to adjustment for demographic factors such as ethnic background and social deprivation. Quantitative and qualitative studies are needed to better understand the factors contributing to this risk. Robust informatics solutions for HCW exposure data are essential to inform occupational monitoring.

National Early Warning Score 2 (NEWS2) to identify inpatient COVID-19 deterioration: a retrospective analysis

INTRODUCTION

We sought to provide the first report of the use of NEWS2 monitoring to pre-emptively identify clinical deterioration within hospitalised COVID-19 patients.

METHODS

Consecutive adult admissions with PCR-confirmed COVID-19 were included in this single-centre retrospective UK cohort study. We analysed all electronic clinical observations recorded within 28 days of admission until discharge or occurrence of a serious event, defined as any of the following: initiation of respiratory support, admission to intensive care, initiation of end of life care, or in-hospital death.

RESULTS

133/296 (44.9%) patients experienced at least one serious event. NEWS2 ≥ 5 heralded the first occurrence of a serious event with sensitivity 0.98 (95% CI 0.96-1.00), specificity 0.28 (0.21-0.35), positive predictive value (PPV) 0.53 (0.47-0.59), and negative predictive value (NPV) 0.96 (0.90-1.00). The NPV (but not PPV) of NEWS2 monitoring exceeded that of other early warning scores including the Modified Early Warning Score (MEWS) (0.59 [0.52-0.66], p<0.001) and quick Sepsis Related Organ Failure Assessment (qSOFA) score (0.58 [0.51-0.65], p<0.001).

CONCLUSION

Our results support the use of NEWS2 monitoring as a sensitive method to identify deterioration of hospitalised COVID-19 patients, albeit at the expense of a relatively high false-trigger rate.

COVID-19-associated hyperinflammation and escalation of patient care: a retrospective longitudinal cohort study

Background

A subset of patients with severe COVID-19 develop a hyperinflammatory syndrome, which might contribute to morbidity and mortality. This study explores a specific phenotype of COVID-19-associated hyperinflammation (COV-HI), and its associations with escalation of respiratory support and survival.

Methods

In this retrospective cohort study, we enrolled consecutive inpatients (aged ≥18 years) admitted to University College London Hospitals and Newcastle upon Tyne Hospitals in the UK with PCR-confirmed COVID-19 during the first wave of community-acquired infection. Demographic data, laboratory tests, and clinical status were recorded from the day of admission until death or discharge, with a minimum follow-up time of 28 days. We defined COV-HI as a C-reactive protein concentration greater than 150 mg/L or doubling within 24 h from greater than 50 mg/L, or a ferritin concentration greater than 1500 μg/L. Respiratory support was categorised as oxygen only, non-invasive ventilation, and intubation. Initial and repeated measures of hyperinflammation were evaluated in relation to the next-day risk of death or need for escalation of respiratory support (as a combined endpoint), using a multi-level logistic regression model.

Findings

We included 269 patients admitted to one of the study hospitals between March 1 and March 31, 2020, among whom 178 (66%) were eligible for escalation of respiratory support and 91 (34%) patients were not eligible. Of the whole cohort, 90 (33%) patients met the COV-HI criteria at admission. Despite having a younger median age and lower median Charlson Comorbidity Index scores, a higher proportion of patients with COV-HI on admission died during follow-up (36 [40%] of 90 patients) compared with the patients without COV-HI on admission (46 [26%] of 179). Among the 178 patients who were eligible for full respiratory support, 65 (37%) met the definition for COV-HI at admission, and 67 (74%) of the 90 patients whose respiratory care was escalated met the criteria by the day of escalation. Meeting the COV-HI criteria was significantly associated with the risk of next-day escalation of respiratory support or death (hazard ratio 2·24 [95% CI 1·62–2·87]) after adjustment for age, sex, and comorbidity.

Interpretation

Associations between elevated inflammatory markers, escalation of respiratory support, and survival in people with COVID-19 indicate the existence of a high-risk inflammatory phenotype. COV-HI might be useful to stratify patient groups in trial design.

Funding

None.

Lack of association between clinical and ultrasound measures of disease activity in rheumatoid arthritis remission

OBJECTIVES

The objective of this study was to assess the prevalence of ultrasound (US) abnormalities and association with clinical parameters in rheumatoid arthritis (RA) clinical remission.

METHODS

Patients with established RA in clinical remission (DAS28-CRP < 2.4) taking conventional synthetic disease-modifying anti-rheumatic drugs were recruited as part of the Biomarkers of Remission in Rheumatoid Arthritis (BioRRA) Study. In addition, patients from the Newcastle Early Arthritis Clinic (NEAC) with early active RA (DAS28-CRP > 2.4) or seronegative non-inflammatory arthralgia (NIA) were studied as positive and negative controls, respectively. The association between individual dependent variables (synovial power Doppler and greyscale, tenosynovial greyscale, and erosions) and clinical parameters was assessed by multivariate ordinal logistic regression, with adjustment for multiple testing.

RESULTS

A total of 294 patients were included: 66 RA in remission, 146 active RA, and 82 NIA. Within the active RA group, significant associations were observed between swollen joint count and higher total synovial greyscale score (OR 1.17 95% CI 1.08-1.26, p < 0.001) and higher total synovial power Doppler score (OR 1.20, 95% CI 1.12-1.30, p < 0.001). No significant associations were observed for the NIA group. In the RA remission group, US abnormalities were frequently observed and comparable for both DAS28-CRP and 2011 ACR/EULAR Boolean remission, with no significant association with clinical parameters identified.

CONCLUSION

We observed widespread subclinical US findings in RA patients in clinical remission, even when remission is defined using the stringent ACR/EULAR Boolean criteria. In contrast to active disease, synovial power Doppler failed to show significant association with any of the clinical parameters in RA remission. Our results suggest that clinical and US examinations are non-overlapping in evaluating RA remission, challenging the proposition of US-driven management strategies in this setting.

Predicting drug-free remission in rheumatoid arthritis: A prospective interventional cohort study

BACKGROUND

Many patients with rheumatoid arthritis (RA) achieve disease remission with modern treatment strategies. However, having achieved this state, there are no tests that predict when withdrawal of therapy will result in drug-free remission rather than flare. We aimed to identify predictors of drug-free remission in RA.

METHODS

The Biomarkers of Remission in Rheumatoid Arthritis (BioRRA) Study was a unique, prospective, interventional cohort study of complete and abrupt cessation of conventional synthetic disease-modifying anti-rheumatic drugs (DMARDs). Patients with RA of at least 12 months duration and in clinical and ultrasound remission discontinued DMARDs and were monitored for six months. The primary outcome was time-to-flare, defined as disease activity score in 28 joints with C-reactive protein (DAS28-CRP) ≥ 2.4. Baseline clinical and ultrasound measures, circulating inflammatory biomarkers, and peripheral CD4+ T cell gene expression were assessed for their ability to predict time-to-flare and flare/remission status by Cox regression and receiver-operating characteristic (ROC) analysis respectively.

RESULTS

23/44 (52%) eligible patients experienced an arthritis flare after a median (IQR) of 48 (31.5-86.5) days following DMARD cessation. A composite score incorporating five baseline variables (three transcripts [FAM102B, ENSG00000228010, ENSG00000227070], one cytokine [interleukin-27], one clinical [Boolean remission]) differentiated future flare from drug-free remission with an area under the ROC curve of 0.96 (95% CI 0.91-1.00), sensitivity 0.91 (0.78-1.00) and specificity 0.95 (0.84-1.00).

CONCLUSION

We provide proof-of-concept evidence for predictors of drug-free remission in RA. If validated, these biomarkers could help to personalize immunosuppressant withdrawal: a therapy paradigm shift with ensuing patient and economic benefits.

"Living a normal life": a qualitative study of patients' views of medication withdrawal in rheumatoid arthritis

Background

Withdrawal of disease-modifying anti-rheumatic drugs (DMARDs) once disease remission is achieved is endorsed by current international rheumatoid arthritis (RA) management guidelines. However, very little data exists concerning patients’ views of this practice. In this qualitative study, we aimed to explore patients’ perspectives on DMARD withdrawal in the setting of established RA.

Methods

In this qualitative interview study, patients with stable established RA were recruited from rheumatology outpatient clinics at a large UK teaching hospital. The perceived advantages and disadvantages of DMARDs and views on DMARD withdrawal were explored in semi-structured interviews. Interview transcripts were analysed using standard qualitative techniques to construct an analytical framework.

Results

Thirteen participants (8 female, median [IQR] age 65 [61–73]) expressed their views of DMARD treatment in the context of their “normal lives”. For some patients, disadvantages such as medication side-effects and the inconvenience of safety monitoring were sufficient hindrances to their lifestyle to justify DMARD withdrawal. However, patients who were vulnerable to loss of physical function, or who had prior experience of severe rheumatoid arthritis, expressed a strong preference against DMARD withdrawal, viewing the potential for increased pain and future disability as unacceptable risks.

Conclusions

Patients view DMARD withdrawal in the context of either restoring or threatening their “normal lives”. In this model, social and personal factors play a crucial role in influencing patients’ opinions of DMARD therapy beyond a simple consideration of medication side-effects alone. A formulaic approach to DMARD withdrawal determined and imposed by clinicians would not be successful. Instead, the discussion of DMARD withdrawal should take place with the identification of patients’ priorities and in the context of their personal disease experiences.

Trial registration

clinicaltrials.gov (NCT02064400), retrospectively registered 17 February 2014.

Electronic supplementary material

The online version of this article (10.1186/s41927-019-0070-y) contains supplementary material, which is available to authorized users.

Novel therapies for immune-mediated inflammatory diseases: What can we learn from their use in rheumatoid arthritis, spondyloarthritis, systemic lupus erythematosus, psoriasis, Crohn's disease and ulcerative colitis?

The past three decades have witnessed remarkable advances in our ability to target specific elements of the immune and inflammatory response, fuelled by advances in both biotechnology and disease knowledge. As well as providing superior treatments for immune-mediated inflammatory diseases (IMIDs), such therapies also offer unrivalled opportunities to study the underlying immunopathological basis of these conditions.In this review, we explore recent approaches to the treatment of IMIDs and the insights to pathobiology that they provide. We review novel biologic agents targeting the T-helper 17 axis, including therapies directed towards interleukin (IL)-17 (secukinumab, ixekizumab, bimekizumab), IL-17R (brodalumab), IL-12/23p40 (ustekinumab, briakinumab) and IL-23p19 (guselkumab, tildrakizumab, brazikumab, risankizumab, mirikizumab). We also present an overview of biologics active against type I and II interferons, including sifalumumab, rontalizumab, anifrolumab and fontolizumab. Emerging strategies to interfere with cellular adhesion processes involved in lymphocyte recruitment are discussed, including both integrin blockade (natalizumab, vedolizumab, etrolizumab) and sphingosine-1-phosphate receptor inhibition (fingolimod, ozanimod). We summarise the development and recent application of Janus kinase (JAK) inhibitors in the treatment of IMIDs, including first-generation pan-JAK inhibitors (tofacitinib, baricitinib, ruxolitinib, peficitinib) and second-generation selective JAK inhibitors (decernotinib, filgotinib, upadacitinib). New biologics targeting B-cells (including ocrelizumab, veltuzumab, tabalumab and atacicept) and the development of novel strategies for regulatory T-cell modulation (including low-dose IL-2 therapy and Tregitopes) are also discussed. Finally, we explore recent biotechnological advances such as the development of bispecific antibodies (ABT-122, COVA322), and their application to the treatment of IMIDs.

Use of structured musculoskeletal examination routines in undergraduate medical education and postgraduate clinical practice - a UK survey

BACKGROUND

Structured examination routines have been developed as educational resources for musculoskeletal clinical skills teaching, including Gait-Arms-Legs-Spine (GALS), Regional Examination of the Musculoskeletal System (REMS) and paediatric GALS (pGALS). In this study, we aimed to assess the awareness and use of these examination routines in undergraduate medical teaching in UK medical schools and UK postgraduate clinical practice.

METHODS

Electronic questionnaires were distributed to adult and paediatric musculoskeletal teaching leads at UK medical schools and current UK doctors in training.

RESULTS

Responses were received from 67 tutors representing teaching at 22/33 [67 %] of all UK medical schools, and 70 trainee doctors across a range of postgraduate training specialities. There was widespread adoption, at responding medical schools, of the adult examination routines within musculoskeletal teaching (GALS: 14/16 [88 %]; REMS: 12/16 [75 %]) and assessment (GALS: 13/16 [81 %]; REMS: 12/16 [75 %]). More trainees were aware of GALS (64/70 [91 %]) than REMS (14/67 [21 %]). Of the 39 trainees who used GALS in their clinical practice, 35/39 [90 %] reported that it had improved their confidence in musculoskeletal examination. Of the 17/22 responding medical schools that included paediatric musculoskeletal examination within their curricula, 15/17 [88 %] used the pGALS approach and this was included within student assessment at 4 medical schools.

CONCLUSIONS

We demonstrate the widespread adoption of these examination routines in undergraduate education and significant uptake in postgraduate clinical practice. Further study is required to understand their impact upon clinical performance.

Management of mammographic indeterminate lesions. First place winner of the Conrad Jobst Award in the Gold Medal paper competition

The positive predictive value of mammography in nonpalpable malignancy, only 20 to 25 per cent, could be improved with better mammographic criteria for lesions not requiring biopsy. The outcomes of 89 patients with indeterminate lesions were reviewed to determine whether these lesions could be managed safely by observation rather than biopsy. Indeterminate lesions were defined as 1) tightly clustered, nonlinear calcifications (> 5 within 1 cm of tissue); 2) dominant, well-circumscribed soft-tissue masses (< or = 1 cm2); or 3) asymmetric density. Lesions not immediately undergoing biopsy were followed with frequent-interval mammography. Twenty-two lesions (26%) underwent immediate biopsy, and 2 of these demonstrated carcinoma in situ with microinvasion. Sixty-seven lesions (74%) were observed (median follow-up, 34 months), and 2 (2.5%) proved to be malignant, for an overall malignancy rate of 4.5 per cent. All malignancies were stage I, and the patients remain alive with no evidence of disease (average follow-up, 24 months). Sixty patients were spared unnecessary biopsy, decreasing potential wire-directed biopsies by 25 per cent. The positive predictive value of mammography increased from 21 to 32 per cent over the period. Indeterminate lesions can be safely followed with frequent ipsilateral mammography, reserving biopsy for lesions that progress. Management schemes such as this one can be used to decrease the number of negative wire-directed biopsies.

Angiographic evidence of basilar artery constriction in the rabbit: a new model of vasospasm

The main objective of this study was to produce angiographic evidence of basilar artery constriction using the rabbit model. The technique described involves the transdural injection of blood into the cisterna magna on two different days. The results obtained show that vasoconstriction occurs over a time period that is comparable in duration to that seen in patients undergoing vasospasm as a result of subarachnoid hemorrhage. Further investigation should be done to evaluate the usefulness of the rabbit model as a verifiable tool in studying the etiology of vasospasm.

High-flow angiopathy: cerebral blood vessel changes in experimental chronic arteriovenous fistula

Profound vascular damage secondary to high-flow extracranial states has been well characterized. However, changes in cerebral vasculature secondary to high-flow states have not been studied. To determine changes related to high-flow states in cerebral vessels, a rabbit model was developed in which torrential flow was created in the vertebrals, carotids, basilar, and vessels of the circle of Willis by means of a carotid-jugular shunt after ligation of the proximal carotid. The clinical, angiographic, and histologic changes noted in the animal model include: abrupt clinical deterioration after a variable interval with some animals developing ptosis, afferent vessel dilatation and the development of prominent anastomotic channels, variable cerebral vessel histopathology--related to duration and relative proximity to the shunt--affecting all three vessel layers, plump, irregular, and clumped endothelium, denuded with adherent platelets, irregular, duplicated, and thinned internal elastic membrane, frayed with invasion of the intima by mesenchymal cells, vacuolization and necrosis of the media muscle, and invasion of adventitia by foreign cells and small blood vessels. The high-flow angiopathy seen in this model may help explain vascular changes associated with high-flow cerebral vascular lesions, as well as other types of vascular damage.

Factors influencing zoospore production by Phytophthora cinnamomi in axenic cultui

Factors and procedures found to increase the quantity and consistency of axenic zoospore production in a selected isolate of Phytophthora cinnamomi were (i) the use of single-zoospore cultures of uniform size that were between 48 and 72 h old; (ii) thorough washing of mycelial mats at the time of sporangium induction to remove nutrients; (iii) agitation of the sporulation medium (mineral salt solution) 24 h after the initial induction; (iv) standardization of the volume of the sporulation medium; (v) adequate removal of the sporulation medium and replacement with distilled water before triggering zoospore release; and (vi) placement of colonies that had been induced to sporulate under light. The addition of a purified sporangium stimulatory substance to mycelial mats which had been induced to sporulate enabled the fungus to sporulate under conditions which normally suppressed sporulation in vitro. In the presence of this stimulatory substance, the fungus sporulated prolifically in darkness and with limited quantities of added nutrients. Other isolates of P. cinnamomi responded in a similar manner to many of these factors and procedures.

Behaviour of Phytophthora cinnamomi in soils suppressive and conducive to root rot

Suppression of root rot in avocados caused by Phytophthora cinnamomi was demonstrated in soil from a grove at Tamborine Mt., Queensland. The addition of P. cinnamomi inoculum in amounts sufficient to cause severe root rot of plants in other soils, untreated or steam-air treated at 60°C for 30 min, produced little or no damage in the suppressive soil. Suppressive soil was found to have higher populations of bacteria and actinomycetes than soils conducive to root rot. Few sporangia were formed by P. cinnamomi and P. citrophthora in suppressive soil or soil leachate. The suppression of sporangium formation was found to be microbial and not related to the nutrient level of the soil leachate. Mycelium of P. cinnamomi grew through untreated conducive soils, but developed poorly in untreated suppressive soils. The fungus grew readily through all soils steam-air treated at 49, 60 and 100�C for 30 min. After 6 weeks the isolation frequency of P. cinnamomi had declined in the suppressive soil treated at 49 or 60°C for 30 min. Exchangeable calcium and magnesium, nitrogen, and organic matter were higher in soils suppressive to root rot than in conducive soils. Rain-forest soil, where the pathogen is not damaging, was comparable in this respect to the suppressive soil.

Association of bacteria with sporangium formation and breakdown of sporangia in Phytophthora spp

Leachates from different soils extracted at similar moisture potentials varied in their ability to induce sporangium formation, zoospore release and sporangium breakdown in Phytophthora spp. Sporangium production by P. cinnamomi did not occur in soil leachates heated at 40–50°C for 10 min or in soils treated with steam-air at 60° for 30 min. No evidence was obtained that Pseudomonas or Chromobacterium spp. were involved in the induction of sporangium formation. Chemotaxis of bacteria to sporangia occurred at zoospore release. Where sporangial breakdown occurred, the chemotaxis persisted for a longer period as the cytoplasm was withdrawn from the sporangial wall to be released eventually, without zoospore formation, through the papilla. The bacteria were oriented at right angles to the sporangial wall. Electron micrographs showed that in the vicinity of a bacterium, the outer, thin, electron-dense layer of the sporangial wall had disappeared and the cytoplasm of the sporangium had withdrawn from the cell wall.

The effect of inoculation of seed with antagonists of Rhizoctonia solani on the growth of wheat

Biological control of Rhizoctonia solani on wheat by seed inoculation with microorganisms was investigated. Initially inoculants were selected from bacteria and actinomycetes isolated from two soils and screened for antagonism to R. solani on agar. Of 148 isolates tested on agar, 96 were antagonistic to R. solani and of these 42 were added to pasteurized soil sown with peppers and inoculated with the pathogen. Seven isolates which controlled disease were screened further as seed inoculants of wheat in pasteurized and field soils inoculated with R. solani. Four inoculants, viz. Streptomyces griseus 2-A24 and three Bacillus subtilis isolates 1-B80, 1-B77 and 1-B68, significantly reduced symptoms caused by R. solani and also increased grain yield and dry matter of wheat. S. griseus 2-A24 and B. subtilis 1-B80 increased grain yield by 30% over controls. The magnitude of these differences suggests that biological control and growth stimulation are involved in yield increases.

Bacteria and actinomycetes antagonistic to fungal root pathogens in Australian soils

Techniques are described which make possible the large.scale isolation and screening of potential antagonists to fungal root pathogens. Sixty selected soils from five States have been sampled. Of more than 3500 isolates tested, about 40% inhibited one or more of nine pathogens on agar, and about 4% were effective in soil; a lower percentage might be effective under commercial conditions. Such large. scale methods are essential to success.

Ultrastructure and cleavage of chlamydospore chains of Thielaviopsis basicola

Electron microscopy revealed that numerous spherical or ellipsoidal globules of reserve nutrient material fill the chlamydospore cells, with cytoplasm as a thin film between these globules. The basal cell of the chain is not a chlamydospore; it is filled with cytoplasm and does not contain these globules. Its plasma membrane, nucleus, mitochondria, lomasomes, and endoplasmic reticulum are evident in ultra-thin section. The walls of chlamydospore cells are thick and without distinct layers, except for an electron-dense outer region and a more electron-transparent inner region. Chlamydospore cells in the chain are separated by a very thin electron-transparent binding layer. A thin two-layered envelope surrounds the entire chain. When chlamydospore chains are treated with chitinase, this envelope remains attached around single separated cells, rather than dissolving away. Cytoplasm of cells in the chain is continuous through septal pores. The end walls of the cells become the opercula after the cells are freed from the chain. The germ tube always emerges at the side where the operculum opens, never through the septal pore.

System for Reporting Symposium Discussions

The system described was effective in obtaining a complete record of the discussions which arose during a week-long symposium with over 300 participants. Each individual wrote a publishable summary of his question or comment on a special numbered card immediately after speaking. This not only provided an accurate report but greatly facilitated preparation for publication.