Multiorgan MRI findings after hospitalisation with COVID-19 in the UK (C-MORE): a prospective, multicentre, observational cohort study

INTRODUCTION

The multiorgan impact of moderate to severe coronavirus infections in the post-acute phase is still poorly understood. We aimed to evaluate the excess burden of multiorgan abnormalities after hospitalisation with COVID-19, evaluate their determinants, and explore associations with patient-related outcome measures.

METHODS

In a prospective, UK-wide, multicentre MRI follow-up study (C-MORE), adults (aged ≥18 years) discharged from hospital following COVID-19 who were included in Tier 2 of the Post-hospitalisation COVID-19 study (PHOSP-COVID) and contemporary controls with no evidence of previous COVID-19 (SARS-CoV-2 nucleocapsid antibody negative) underwent multiorgan MRI (lungs, heart, brain, liver, and kidneys) with quantitative and qualitative assessment of images and clinical adjudication when relevant. Individuals with end-stage renal failure or contraindications to MRI were excluded. Participants also underwent detailed recording of symptoms, and physiological and biochemical tests. The primary outcome was the excess burden of multiorgan abnormalities (two or more organs) relative to controls, with further adjustments for potential confounders. The C-MORE study is ongoing and is registered with ClinicalTrials.gov, NCT04510025.

FINDINGS

Of 2710 participants in Tier 2 of PHOSP-COVID, 531 were recruited across 13 UK-wide C-MORE sites. After exclusions, 259 C-MORE patients (mean age 57 years [SD 12]; 158 [61%] male and 101 [39%] female) who were discharged from hospital with PCR-confirmed or clinically diagnosed COVID-19 between March 1, 2020, and Nov 1, 2021, and 52 non-COVID-19 controls from the community (mean age 49 years [SD 14]; 30 [58%] male and 22 [42%] female) were included in the analysis. Patients were assessed at a median of 5·0 months (IQR 4·2-6·3) after hospital discharge. Compared with non-COVID-19 controls, patients were older, living with more obesity, and had more comorbidities. Multiorgan abnormalities on MRI were more frequent in patients than in controls (157 [61%] of 259 vs 14 [27%] of 52; p<0·0001) and independently associated with COVID-19 status (odds ratio [OR] 2·9 [95% CI 1·5-5·8]; padjusted=0·0023) after adjusting for relevant confounders. Compared with controls, patients were more likely to have MRI evidence of lung abnormalities (p=0·0001; parenchymal abnormalities), brain abnormalities (p<0·0001; more white matter hyperintensities and regional brain volume reduction), and kidney abnormalities (p=0·014; lower medullary T1 and loss of corticomedullary differentiation), whereas cardiac and liver MRI abnormalities were similar between patients and controls. Patients with multiorgan abnormalities were older (difference in mean age 7 years [95% CI 4-10]; mean age of 59·8 years [SD 11·7] with multiorgan abnormalities vs mean age of 52·8 years [11·9] without multiorgan abnormalities; p<0·0001), more likely to have three or more comorbidities (OR 2·47 [1·32-4·82]; padjusted=0·0059), and more likely to have a more severe acute infection (acute CRP >5mg/L, OR 3·55 [1·23-11·88]; padjusted=0·025) than those without multiorgan abnormalities. Presence of lung MRI abnormalities was associated with a two-fold higher risk of chest tightness, and multiorgan MRI abnormalities were associated with severe and very severe persistent physical and mental health impairment (PHOSP-COVID symptom clusters) after hospitalisation.

INTERPRETATION

After hospitalisation for COVID-19, people are at risk of multiorgan abnormalities in the medium term. Our findings emphasise the need for proactive multidisciplinary care pathways, with the potential for imaging to guide surveillance frequency and therapeutic stratification.

FUNDING

UK Research and Innovation and National Institute for Health Research.

Cytomegalovirus infection is a risk factor for venous thromboembolism in ANCA-associated vasculitis

BACKGROUND

Venous thromboembolism (VTE) is a common complication in patients with anti-neutrophil cytoplasm antibody (ANCA)-associated vasculitides (AAV) and confers significant morbidity and mortality. Both acute and past cytomegalovirus (CMV) infection have been identified as risk factors for VTE in immunocompetent and immunosuppressed individuals. Here, we examine whether past exposure to CMV is a risk factor for VTE amongst patients with AAV.

METHODS

We retrospectively analysed outcomes of patients with a new diagnosis of AAV from a UK cohort. All confirmed cases of VTE where CMV IgG serology was available were recorded. Retrospective collection of the same data for patients at a North American centre was used as a validation cohort.

RESULTS

VTE was common with 12% of patients from the study cohort (total 259 patients) developing an event during the median follow-up period of 8.5 years of which 60% occurred within the first 12 months following diagnosis. Sixteen percent of CMV seropositive patients developed a VTE compared with 5% of patients who were seronegative (p = 0.007) and CMV seropositivity remained an independent predictor of VTE in multivariable analysis (HR 2.96 [1.094-8.011] p = 0.033). CMV seropositivity at diagnosis was confirmed as a significant risk factor for VTE in the American validation cohort (p = 0.032).

CONCLUSIONS

VTE is common in patients with AAV, especially within the first year of diagnosis. Past infection with CMV is an independent risk factor associated with VTE in AAV.

Clinical characteristics with inflammation profiling of long COVID and association with 1-year recovery following hospitalisation in the UK: a prospective observational study

BACKGROUND

No effective pharmacological or non-pharmacological interventions exist for patients with long COVID. We aimed to describe recovery 1 year after hospital discharge for COVID-19, identify factors associated with patient-perceived recovery, and identify potential therapeutic targets by describing the underlying inflammatory profiles of the previously described recovery clusters at 5 months after hospital discharge.

METHODS

The Post-hospitalisation COVID-19 study (PHOSP-COVID) is a prospective, longitudinal cohort study recruiting adults (aged ≥18 years) discharged from hospital with COVID-19 across the UK. Recovery was assessed using patient-reported outcome measures, physical performance, and organ function at 5 months and 1 year after hospital discharge, and stratified by both patient-perceived recovery and recovery cluster. Hierarchical logistic regression modelling was performed for patient-perceived recovery at 1 year. Cluster analysis was done using the clustering large applications k-medoids approach using clinical outcomes at 5 months. Inflammatory protein profiling was analysed from plasma at the 5-month visit. This study is registered on the ISRCTN Registry, ISRCTN10980107, and recruitment is ongoing.

FINDINGS

2320 participants discharged from hospital between March 7, 2020, and April 18, 2021, were assessed at 5 months after discharge and 807 (32·7%) participants completed both the 5-month and 1-year visits. 279 (35·6%) of these 807 patients were women and 505 (64·4%) were men, with a mean age of 58·7 (SD 12·5) years, and 224 (27·8%) had received invasive mechanical ventilation (WHO class 7-9). The proportion of patients reporting full recovery was unchanged between 5 months (501 [25·5%] of 1965) and 1 year (232 [28·9%] of 804). Factors associated with being less likely to report full recovery at 1 year were female sex (odds ratio 0·68 [95% CI 0·46-0·99]), obesity (0·50 [0·34-0·74]) and invasive mechanical ventilation (0·42 [0·23-0·76]). Cluster analysis (n=1636) corroborated the previously reported four clusters: very severe, severe, moderate with cognitive impairment, and mild, relating to the severity of physical health, mental health, and cognitive impairment at 5 months. We found increased inflammatory mediators of tissue damage and repair in both the very severe and the moderate with cognitive impairment clusters compared with the mild cluster, including IL-6 concentration, which was increased in both comparisons (n=626 participants). We found a substantial deficit in median EQ-5D-5L utility index from before COVID-19 (retrospective assessment; 0·88 [IQR 0·74-1·00]), at 5 months (0·74 [0·64-0·88]) to 1 year (0·75 [0·62-0·88]), with minimal improvements across all outcome measures at 1 year after discharge in the whole cohort and within each of the four clusters.

INTERPRETATION

The sequelae of a hospital admission with COVID-19 were substantial 1 year after discharge across a range of health domains, with the minority in our cohort feeling fully recovered. Patient-perceived health-related quality of life was reduced at 1 year compared with before hospital admission. Systematic inflammation and obesity are potential treatable traits that warrant further investigation in clinical trials.

FUNDING

UK Research and Innovation and National Institute for Health Research.

Antibody responses after first and second Covid-19 vaccination in patients with chronic lymphocytic leukaemia

B-cell chronic lymphocytic leukaemia (CLL) is associated with immunosuppression and patients are at increased clinical risk following SARS-CoV-2 infection. Covid-19 vaccines offer the potential for protection against severe infection but relatively little is known regarding the profile of the antibody response following first or second vaccination. We studied spike-specific antibody responses following first and/or second Covid-19 vaccination in 299 patients with CLL compared with healthy donors. 286 patients underwent extended interval (10-12 week) vaccination. 154 patients received the BNT162b2 mRNA vaccine and 145 patients received ChAdOx1. Blood samples were taken either by venepuncture or as dried blood spots on filter paper. Spike-specific antibody responses were detectable in 34% of patients with CLL after one vaccine (n = 267) compared to 94% in healthy donors with antibody titres 104-fold lower in the patient group. Antibody responses increased to 75% after second vaccine (n = 55), compared to 100% in healthy donors, although titres remained lower. Multivariate analysis showed that current treatment with BTK inhibitors or IgA deficiency were independently associated with failure to generate an antibody response after the second vaccine. This work supports the need for optimisation of vaccination strategy in patients with CLL including the potential utility of booster vaccines.

Cytomegalovirus seropositivity is independently associated with cardiovascular disease in non-dialysis dependent chronic kidney disease

BACKGROUND

Cardiovascular disease (CVD) is the leading cause of early death in patients with chronic kidney disease (CKD). Previous work has described an association between Cytomegalovirus (CMV) seropositivity and CVD amongst patients with dialysis dependent end stage renal disease. Whether CMV seropositivity is associated with CVD in non-dialysis dependent CKD has not been established.

AIM

Investigate whether past CMV infection is associated with prevalent CVD in patients with non-dialysis dependent CKD.

DESIGN

A retrospective observational study using the Renal Impairment in Secondary Care cohort, a study evaluating bio-clinical determinants of outcomes in patients with progressive CKD.

METHODS

We assayed cryopreserved serum samples collected at inception for anti-CMV IgG antibodies from 764 patients with stages 2 to 5 CKD (pre-dialysis) and investigated its relationship with prevalent CVD.

RESULTS

Median estimated glomerular filtration was 24 ml/min/1.73 m2 (IQR 19-32). Sixty-eight percent of patients were CMV seropositive. CMV seropositivity was associated with older age, non-Caucasian ethnicity, diabetes and higher social deprivation index score. On univariable analysis, CMV seropositivity correlated with higher systolic blood pressure (P = 0.044), prevalent CVD (P < 0.001), ischaemic heart disease (P < 0.001) and cerebrovascular disease (P = 0.022). On multivariable analysis, CMV seropositive patients nearly twice as likely to have CVD compared to seronegative patients [Odds Ratio (OR) = 1.998, CI 1.231-3.242, P = 0.005].

CONCLUSIONS

In patients with non-dialysis CKD, CMV seropositivity is independently associated with a higher prevalence of CVD.

The application of a haemorrhage assessment tool in evaluating control of bleeding in a pilot trauma haemorrhage trial

OBJECTIVES

To determine whether it was feasible to use a haemorrhage assessment tool (HAT) within a trauma trial and whether the data obtained could differentiate patients who had achieved haemostasis.

BACKGROUND

Major haemorrhage is one of the leading causes of death worldwide, affecting 40% of trauma patients. Clinical trials evaluating haemostatic interventions often use transfusion outcomes as a primary endpoint. Transfusion is highly dependent on local practice, limiting its reliability as a robust, transferable endpoint.

METHODS

A five-point HAT questionnaire was applied to participants enrolled into the EFIT-1 trial. This RCT evaluated the feasibility of administering a 6 g fibrinogen concentrate to patients with severe trauma haemorrhage.

RESULTS

Of participants, 98% completed a HAT; 75% participants had 'achieved haemostasis' at the time of tool completion, as determined by clinical acumen alone. HAT scores were able to differentiate which participants required transfusion after 3 h. Of participants, 56% were transfused red blood cells when they scored 0-2, compared to 17% with HAT scores between 3 and 5.

CONCLUSION

This study has confirmed the feasibility of using a HAT during the emergency care of patients suffering trauma haemorrhage, and future studies should be conducted to determine its value as an endpoint in haemostasis studies.

Alloreactive T cells develop in the very early period following human stem cell transplantation and are characterised by a range of novel features

Allogeneic stem cell transplantation can cure some patients with hematopoietic malignancy but relies on development of a donor T cell alloreactive immune response which develops very early but is difficult to study due to intense lymphopenia. We characterised the phenotype and functional profile of T cells at day 14 in patients undergoing transplantation. T cells were present at very low number but displayed intense proliferation with strong cytokine production. Oligoclonal expansions at day 14 came to represent a substantial fraction of the established T cell pool and were recruited into tissues affected by graft-versus-host disease. Transcriptional analysis uncovered a range of potential targets for immune manipulation including OX40L, TWEAK and CD70. These findings reveal that recognition of alloantigen rapidly drives naïve T cells towards a unique phenotype characterised by intense functional activation. Moreover they demonstrate that early clonal T cell responses are recruited to sites of subsequent tissue damage and provide a range of novel targets for potential therapeutic immunomodulation.

Fourteen days of etoricoxib 60 mg improves pain, hyperalgesia and physical function in individuals with knee osteoarthritis: a randomized controlled trial

OBJECTIVE

Mounting evidence points to the heterogeneity of osteoarthritis (OA) pain, increasing the need for more comprehensive assessment of the efficacy of standard interventions. This study investigated whether 14 days of the selective Cox-2 inhibitor etoricoxib (60 mg/day) would modify self-report of pain intensity and quality, and physical measures of hyperalgesia and function in individuals with knee OA.

DESIGN

This double-blind placebo-controlled trial included 80 community-recruited volunteers with painful knee OA (≥3/10 VAS), randomly allocated to Active or Placebo groups. Self-report measures of pain, stiffness, function Western Ontario and McMaster University Osteoarthritis Index (WOMAC) and pain quality (PainDETECT, Pain Quality Assessment Scale [PQAS]) and physical measures of locomotion and local (knee) and widespread (elbow) hyperalgesia were assessed at Days 0, 4 and 14. Repeated Measures ANOVA analysed group differences.

RESULTS

Significant group × time interaction effects were found for all measures of pain (all p < 0.001), with WOMAC pain sub-score improving by 30.7% by Day 14 and index knee mechanical hyperalgesia improving by 32.6%, whilst Placebo group values worsened. Both self-report and physical tests of function improved (p < 0.001-p = 0.006): WOMAC-function by 28.4%, sit-to-stand and walk time by 13%, pain during locomotion tasks by 12.4-32.6%. Pain quality also significantly improved for the Active and declined for the Placebo group (p < 0.001): PainDETECT score reduced by 23.6% and PQAS paroxsysmal and surface sub-scores by 36.9% and 29.4%. There were also significant improvements in local cold hyperalgesia and widespread mechanical hyperalgesia (10-13.8%).

CONCLUSION

Just 14 days of etoricoxib significantly improves pain intensity and quality, function and local and widespread hyperalgesia, measured by both self-report and physical tests.

Cytomegalovirus infection is associated with an increase in systolic blood pressure in older individuals

BACKGROUND

Cytomegalovirus (CMV) is a chronic infection that is widely distributed in the population. CMV infects a range of tissues, including endothelium, and viral replication is suppressed by the host immune system. Infection is associated with increased risk of mortality from vascular disease in older people, but the mechanisms behind this have not been determined.

AIM

We investigated the association between CMV infection and cardiovascular phenotype in a cohort of healthy elderly donors.

DESIGN

CMV serostatus and cardiovascular parameters were determined in the Lothian Birth cohort, which comprises 1091 individuals aged 70 years in whom many environmental, biochemical and radiological correlates of vascular function have been determined.

METHODS

CMV serostatus was determined by enzyme-linked immunosorbant assay and correlated with a range of biochemical and phenotypic measures.

RESULTS

Sixty-five percent of participants were CMV seropositive, which indicates chronic infection. The mean sitting systolic blood pressure (SBP) was 149.2 mmHg in CMV seropositive individuals compared with 146.2 mmHg in CMV seronegative subjects (SD 18.7 vs. 19.7; P < 0.017). This association between CMV infection and SBP was not attenuated after adjustment for a wide range of biological and socio-economic factors.

CONCLUSIONS

These data show that CMV infection is associated with an increase in SBP in individuals at age 70 years. The magnitude is comparable to environmental variables such as obesity, diabetes or high salt intake. This is the first evidence to show that a chronic infection may be an important determinant of blood pressure and could have significant implications for the future management of hypertension.

Greatly reduced risk of EBV reactivation in rituximab-experienced recipients of alemtuzumab-conditioned allogeneic HSCT

EBV-associated post-transplant lymphoproliferative disease (PTLD) remains an important complication of allogeneic haematopoietic stem cell transplantation (allo-HSCT). We retrospectively analysed the incidence and risk factors for EBV reactivation in 186 adult patients undergoing consecutive allo-HSCT with alemtuzumab T-cell depletion at a single centre. The cumulative incidence of EBV reactivation was 48% (confidence interval (CI) 41-55%) by 1 year, with an incidence of high-level EBV reactivation of 18% (CI 13-24%); 8 patients were concurrently diagnosed with PTLD. Amongst patients with high-level reactivation 31/38 (82%) developed this within only 2 weeks of first EBV qPCR positivity. In univariate analysis age⩾50 years was associated with significantly increased risk of EBV reactivation (hazard ratio (HR) 1.54, CI 1.02-2.31; P=0.039). Furthermore, a diagnosis of non-Hodgkin lymphoma (NHL) was associated with greatly reduced risk of reactivation (HR 0.10, CI 0.03-0.33; P=0.0001) and this was confirmed in multivariate testing. Importantly, rituximab therapy within 6 months prior to allo-HSCT was also highly predictive for lack of EBV reactivation (HR 0.18, CI 0.07-0.48; P=0.001) although confounding with NHL was apparent. Our data emphasise the risk of PTLD associated with alemtuzumab. Furthermore, we report the clinically important observation that rituximab, administered in the peri-transplant period, may provide effective prophylaxis for PTLD.

Cytomegalovirus-Associated CD4(+) CD28(null) Cells in NKG2D-Dependent Glomerular Endothelial Injury and Kidney Allograft Dysfunction

Emerging data suggest that expansion of a circulating population of atypical, cytotoxic CD4(+) T cells lacking costimulatory CD28 (CD4(+) CD28(null) cells) is associated with latent cytomegalovirus (CMV) infection. The purpose of the current study was to increase the understanding of the relevance of these cells in 100 unselected kidney transplant recipients followed prospectively for a median of 54 months. Multicolor flow cytometry of peripheral blood mononuclear cells before transplantation and serially posttransplantation was undertaken. CD4(+) CD28(null) cells were found predominantly in CMV-seropositive patients and expanded in the posttransplantation period. These cells were predominantly effector-memory phenotype and expressed markers of endothelial homing (CX3CR1) and cytotoxicity (NKG2D and perforin). Isolated CD4(+) CD27(-) CD28(null) cells proliferated in response to peripheral blood mononuclear cells previously exposed to CMV-derived (but not HLA-derived) antigens and following such priming incubation with glomerular endothelium resulted in signs of endothelial damage and apoptosis (release of fractalkine and von Willebrand factor; increased caspase 3 expression). This effect was mitigated by NKG2D-blocking antibody. Increased CD4(+) CD28(null) cell frequencies were associated with delayed graft function and lower estimated glomerular filtration rate at end follow-up. This study suggests an important role for this atypical cytotoxic CD4(+) CD28(null) cell subset in kidney transplantation and points to strategies that may minimize the impact on clinical outcomes.

Primary care management of early stage chronic lymphocytic leukaemia is safe and effective

BACKGROUND

Chronic lymphocytic leukaemia (CLL) is the commonest leukaemia in western society. Most patients are detected incidentally at an early stage and require 'watch and wait' follow-up. In the UK, management of Stage A0 CLL varies with some centres advising regular outpatient haematology follow-up, whereas others recommend management within primary care. The safety and effectiveness of these two management options are currently unknown.

METHODS

An observational retrospective cohort study in outpatient Haematology clinics at Queen Elizabeth Hospital Birmingham (QEH) and Birmingham Heartlands Hospital (BHH) and primary care practices in West Midlands, UK. All patients diagnosed with stable stage A0 CLL since 2002 at BHH or QEH were identified. At BHH, patients were discharged to primary care follow-up, whilst QEH patients remained under haematology for follow-up. Evidence of disease progression, need for treatment and overall mortality was documented.

RESULTS

Two hundred and forty-six Stage A0 CLL patients were identified. One hundred and five (43%) patients were discharged to primary care, whilst 141 (57%) patients were followed up in haematology outpatient clinics. No difference in mortality or need for treatment was found between the two groups. Of those discharged, 93 (66%) remained in primary care.

CONCLUSION

The management of stable-stage A0 CLL within primary or secondary care leads to equivalent clinical outcomes. The prevalence of early-stage CLL is expected to increase with the ageing population and management within primary care should be considered as a potentially effective approach.

Targeting ß2 adrenergic receptors regulate human T cell function directly and indirectly

It is well-established that central nervous system activation affects peripheral blood mononuclear cell (PBMCs) function through the release of the catecholamines (Epi) and norepinephrine (NE), which act on ß2-adrenergic receptors (ß2AR). However, most studies have used non-specific stimulation of cells rather than antigen-specific responses. Likewise, few studies have parsed out the direct effects of ß2AR stimulation on T cells versus indirect effects via adrenergic stimulation of antigen presenting cells (APC). Here we report the effect of salmeterol (Sal), a selective ß2AR agonist, on IFN-γ(+) CD4 and IFN-γ(+) CD8 T cells following stimulation with Cytomegalovirus lysate (CMVL-strain AD169) or individual peptides spanning the entire region of the HCMV pp65 protein (pp65). Cells were also stimulated with Staphylococcal enterotoxin B. Additionally, we investigated the effect of Epi and Sal on cytotoxic cell killing of transfected target cells at the single cell level using the CD107a assay. The results show that Sal reduced the percentage of IFN-γ(+) CD4 and IFN-γ(+) CD8 T cells both when applied directly to isolated T cells, and indirectly via treatment of APC. These inhibitory effects were mediated via a ß2 adrenergic-dependent pathway and were stronger for CD8 as compared to CD4 T cells. Similarly, the results show that Sal suppressed cytotoxicity of both CD8 T and NK cells in vitro following stimulation with Chinese hamster ovary cell line transfected with MICA(*009) (T-CHO) and the human erythromyeloblastoid leukemic (K562) cell line. The inhibitory effect on cytotoxicity following stimulation with T-CHO was stronger in NK cells compared with CD8 T cells. Thus, targeting the ß2AR on lymphocytes and on APC leads to inhibition of inflammatory cytokine production and target cell killing. Moreover, there is a hierarchy of responses, with CD8 T cells and NK cells inhibited more effectively than CD4 T cells.

Post-transplant T cell chimerism predicts graft versus host disease but not disease relapse in patients undergoing an alemtuzumab based reduced intensity conditioned allogeneic transplant

In this multicentre retrospective study we have studied the impact of T cell chimerism on the outcome of 133 patients undergoing an alemtuzumab based reduced intensity conditioning allograft (RIC). The median age of the patients was 50 years (range 42-55 years). 77 patients were transplanted using an HLA identical sibling donor while 56 patients received a fully matched volunteer unrelated donor graft. 64 patients had a lymphoid malignancy and 69 were transplanted for a myeloid malignancy. 38 patients (29%) relapsed with no significant difference in risk of relapse between patients developing full donor and mixed donor chimerism in the T-cell compartment on D+90 and D+180 post transplant. Day 90 full donor T cell chimerism correlated with an increased incidence of acute GVHD according to NIH criteria (p=0.0004) and the subsequent development of chronic GVHD. Consistent with previous observations, our results confirmed a correlation between the establishment of T cell full donor chimerism and acute GVHD in T deplete RIC allografts. However our study failed to identify any correlation between T cell chimerism and relapse risk and challenge the use of pre-emptive donor lymphocyte infusions (DLI) in patients with mixed T cell chimerism transplanted using an alemtuzumab based RIC regimen.

Cord blood T cells retain early differentiation phenotype suitable for immunotherapy after TCR gene transfer to confer EBV specificity

Adoptive T cell therapy can be effective for Epstein-Barr virus (EBV)-associated posttransplant lymphoproliferative disease and melanoma. Transducing high-affinity TCR genes into T lymphocytes is an emerging method to improve potency and specificity of tumor-specific T cells. However, both methods necessitate in vitro lymphocyte proliferation, generating highly differentiated effector cells that display reduced survival and antitumor efficacy postinfusion. TCR-transduction of naive lymphocytes isolated from peripheral blood is reported to provide superior in vivo survival and function. We utilized cord blood (CB) lymphocytes, which comprise mainly naive cells, for transducing EBV-specific TCR. Comparable TCR expression was achieved in adult and CB cells, but the latter expressed an earlier differentiation profile. Further antigen-driven stimulation skewed adult lymphocytes to a late differentiation phenotype associated with immune exhaustion. In contrast, CB T cells retained a less differentiated phenotype after antigen stimulation, remaining CD57-negative but were still capable of antigen-specific polyfunctional cytokine expression and cytotoxicity in response to EBV antigen. CB T cells also retained longer telomeres and in general possessed higher telomerase activity indicative of greater proliferative potential. CB lymphocytes therefore have qualities indicating prolonged survival and effector function favorable to immunotherapy, especially in settings where donor lymphocytes are unavailable such as in solid organ and CB transplantation.

Cytomegalovirus-seropositivity has a profound influence on the magnitude of major lymphoid subsets within healthy individuals

Cytomegalovirus (CMV) infects most individuals and elicits a strong CMV-specific immune response. We have studied the influence of CMV-seropositivity on the size of lymphoid subsets in healthy donors and demonstrate that the virus substantially modulates the peripheral lymphoid pool. CD8(+) T cell numbers are increased in all CMV-seropositive individuals because of a striking 60% increment in the CD8(+) T cell memory pool. The CD45RA(+) resting memory pool is doubled after CMV infection and increases further with age. The magnitude of the naïve CD8(+) T cell pool is dramatically reduced in CMV-seropositive individuals at all ages, and this accelerates the physiological decline by approximately 40 years. The number of CD4(+) effector memory T cells is increased in CMV-seropositive individuals and is differentially accommodated by a reduction in the number of naïve and central memory CD4(+) T cells in young and elderly donors respectively. CMV-seropositivity also increases the total number of B cells in older donors and suppresses the number of CD5(+) B cells. These data reveal that CMV has a profound influence on the immune system of all healthy individuals and add to growing concern regarding the clinical and immunomodulatory significance of CMV infection in healthy donors.

Ethnic variability in human leukocyte antigen-E haplotypes

Human leukocyte antigen-E (HLA-E) is an important nonclassical major histocompatibility complex (MHC) class I (Ib) molecule that acts as the ligand for NKG2A/B/C receptors expressed on natural killer (NK) cells and T cells. Unlike the classical class I molecules, HLA-E is highly conserved in evolution and the biological significance of polymorphism is therefore unclear. Our aim was to investigate the polymorphism in HLA-E gene in three ethnic groups in the UK and to obtain population data relating to any variations observed at this locus. We developed a polymerase chain reaction-sequence-specific primer (PCR-SSP) method for identifying HLA-E single nucleotide polymorphisms (SNPs) in genomic DNA. This was used to investigate the genotype distribution and allele frequency of nine published SNPs in the coding region of HLA-E in 223 Euro-Caucasoid, 60 Afro-Caribbean and 52 Asian healthy individuals. Genotype frequencies were in Hardy-Weinberg equilibrium. No polymorphism was observed for seven previously reported SNPs and these should not be considered polymorphic. However, positions 1114 and 1446 were confirmed as polymorphic and different genotype frequencies were identified at nucleotide position 1114 between the three studied ethnic groups. We present these data together with the intragene haplotype frequencies in these populations. To our knowledge, this is the first description of population frequencies of nine different SNPs in HLA-E in three main large ethnic groups. The data generated from this study will be of importance in the context of describing the effect of HLA-E polymorphism in clinical settings such as transplantation and autoimmune diseases.

Development, impact and outcomes of the Hull Bacteraemia Service

BACKGROUND

Bacteraemia is a significant cause of mortality and healthcare expenditure. Evidence suggests that consultation by an infection specialist may improve outcomes.

AIM

To review the characteristics and outcomes of patients seen by a newly implemented bacteraemia service.

METHODS

Retrospective review of data collected at time of consultation. Economic analyses and benchmarking of outcomes were also performed.

RESULTS

One hundred and fifty-one patients were seen by the service over an 18-month period. Staphylococcus aureus was the most common isolate and central venous lines the most common source. Antibiotics were changed and additional investigations suggested in 62% and 61% of patients, respectively. The 30-day mortality was 19%. Implementation and delivery of the service over the 18-month study period cost pound 22,663 (pound 15,109 per year). The cost per change in antibiotic prescription was pound 244. The cost per 'near-miss' detected was pound 1193. Overall mortality was no higher and possibly lower than in published studies.

CONCLUSION

We believe that this model of care may be suitable for the management of patients with bacteraemia. A study assessing the cost-effectiveness of this approach is required.

Donor HLA-C genotype has a profound impact on the clinical outcome following liver transplantation

Late allograft dysfunction is a significant problem following liver transplantation and its pathogenesis is uncertain. HLA-C is the major inhibitory ligand for killer immunoglobulin-like receptors (KIRs) that regulate the cytotoxic activity of natural killer (NK) cells. HLA-C alleles can be allocated into two groups, termed HLA-C1 and HLA-C2, based on their KIR specificity. HLA-C2 interactions are more inhibiting to NK cell activation. We studied the clinical importance of HLA-C genotype in a large liver transplant cohort and found that possession of at least one HLA-C2 allele by the donor allograft was associated with less histological evidence of chronic rejection and graft cirrhosis, a 16.2% reduction in graft loss (p = 0.003) (hazard ratio: 2.7, 95% CI 1.4-5.3) and a 13.6% improvement in patient survival (p = 0.01) (hazard ratio: 1.9, 95% CI 1.1-3.3) at 10 years. Transplantation of an HLA-C2 homozygous allograft led to a particularly striking 26.5% reduction in graft loss (p < 0.001) (hazard ratio: 7.2, 95% CI 2.2-23.0) at 10 years when compared to HLA-C1 homozygous allografts. Donor HLA-C genotype is therefore a major determinant of clinical outcome after liver transplantation and reveals the importance of NK cells in chronic rejection and graft cirrhosis. Modulation of HLA-C and KIR interactions represents an important novel approach to promote long-term graft and patient survival.

A systematic review and economic evaluation of epoetin alpha, epoetin beta and darbepoetin alpha in anaemia associated with cancer, especially that attributable to cancer treatment

OBJECTIVES

To assess the effectiveness and cost-effectiveness of epoetin alpha, epoetin beta and darbepoetin alpha (referred to collectively in this report as epo) in anaemia associated with cancer, especially that attributable to cancer treatment.

DATA SOURCES

Electronic databases were searched from 2000 (1996 in the case of darbepoetin alpha) to September 2004.

REVIEW METHODS

Using a recently published Cochrane review as the starting point, a systematic review of recent randomised controlled trials (RCTs) comparing epo with best standard was conducted. Inclusion, quality assessment and data abstraction were undertaken in duplicate. Where possible, meta-analysis was employed. The economic assessment consisted of a systematic review of past economic evaluations, an assessment of economic models submitted by the manufacturers of the three epo agents and development of a new individual sampling model (the Birmingham epo model).

RESULTS

In total 46 RCTs were included within this systematic review, 27 of which had been included in the Cochrane systematic review. All 46 trials compared epo plus supportive care for anaemia (including transfusions), with supportive care for anaemia (including transfusions), alone. Haematological response (defined as an improvement by 2 g/dl(-1)) had a relative risk of 3.4 [95% confidence interval (CI) 3.0 to 3.8, 22 RCTs] with a response rate for epo of 53%. The trial duration was most commonly 16-20 weeks. There was little statistical heterogeneity in the estimate of haematological response, and there were no important differences between the subgroups examined. Haemoglobin (Hb) change showed a weighted mean difference of 1.63 g/dl(-1) (95% CI 1.46 to 1.80) in favour of epo. Treatment with erythropoietin in patients with cancer-induced anaemia reduces the number of patients who receive a red blood cell transfusion (RBCT) by an estimated 18%. Health-related quality of life (HRQoL) data were analysed using vote counting and qualitative assessment and a positive effect was observed in favour of an improved HRQoL for patients on epo. Published information on side-effects was of poor quality. New trials provided further evidence of side-effects with epo, particularly thrombic events, but it is still unclear whether these could be accounted for by chance alone. The results of the previous Cochrane review had suggested a survival advantage for epo (HR 0.84, 95% CI 0.69 to 1.02), based on 19 RCTs. The update, based on 28 RCTs, suggests no difference (HR 1.03, 95% CI 0.88 to 1.21). Subgroup analysis suggested some explanations for this heterogeneity, but it is difficult to draw firm conclusions without access to the substantial amounts of missing or unpublished data, or more detailed results from some of the trials with heterogeneous patient populations. The conclusions are, however, broadly in line with those of a Food and Drug Administration (FDA) safety briefing, which recommended that patients with a haemoglobin above 12 g/dl(-1) should not be treated; the target rate of rise in Hb should not be too great, and further carefully conducted trials are required to determine which subgroups of patients may be harmed by the use of these products, in particular through the stimulation of tumour activity. Five published economic evaluations identified from the literature had inconsistent results, with estimates ranging from a cost per quality-adjusted life-year (QALY) under pound 10,000 through to epo being less effective and more costly than standard care. The more favourable evaluations assumed a survival advantage for epo. The three company models submitted each relied on assumed survival gains to achieve relatively low cost per QALY, from pound 13,000 to pound 28,000, but generated estimates from pound 84,000 to pound 159,000 per QALY when no survival gain was assumed. Each of these models relied on Hb levels alone driving utility, and each assumed gradual normalisation of Hb in the standard treatment arm after the end of treatment. The Birmingham epo model followed the company models in regard to the relationship between Hb levels and utility, and also assumed normalisation in the base case. With no survival gain, the incremental cost per QALY was pound 150,000, falling to pound 40,000 when the lower, more favourable, confidence interval for survival was used.

CONCLUSIONS

Epo is effective in improving haematological response and reducing RBCT requirements, and appears to have a positive effect on HRQoL. The incidence of side-effects and effects on survival remains highly uncertain. However, if there is no impact on survival, it seems highly unlikely that epo would be considered a cost-effective use of healthcare resources. The main target for further research should be improving estimates of impact on survival, initially through more detailed secondary research, such as the individual patient data meta-analysis started by the Cochrane group. Further trials may be required, and have been recommended by the FDA, although many trials are in progress, completed but unreported or awaiting mature follow-up. The Birmingham epo model developed as part of this project contains new features that improve its flexibility in exploring different scenarios; further refinement and validation would therefore be of assistance. Finally, further research to resolve uncertainty about other parameters, particularly quality of life, adverse events, and the rate of normalisation, would also be beneficial.

Leptospirosis: a case report of a patient with pulmonary haemorrhage successfully managed with extra corporeal membrane oxygenation

Leptospirosis is a zoonosis of worldwide significance. Pulmonary involvement is common but often mild and of little clinical significance. However, over the last two decades an increasing number of cases have been reported with pulmonary haemorrhage as a prominent feature [Carvalho CR, Bethlem EP. Pulmonary complications of leptospirosis. Clin Chest Med, 2002;23(2):469-78]. These cases are particularly challenging to treat as they often have resistant hypoxaemia despite maximal invasive mechanical ventilation. Consequently, there is a high mortality rate. Here, we present a case of severe leptospirosis complicated by massive pulmonary haemorrhage which was successfully managed by extra corporeal membrane oxygenation (ECMO).

A distinct subset of chemokines dominates the mucosal chemokine response in inflammatory bowel disease

BACKGROUND

Inflammatory bowel disease (IBD) is characterised by intense mucosal recruitment of activated leukocytes. Chemokines determine inflammatory leukocyte recruitment and retention.

AIM

To compare expression of the entire chemokine family within colonic mucosa from IBD patients and uninflamed controls.

METHODS

A microarray of cDNAs, representing every member of this superfamily and their cognate receptors, was hybridised with probes derived from colonoscopic biopsies.

RESULTS

A distinct subset of chemokines, consisting of CXCLs 1-3 and 8 and CCL20, was upregulated in active colonic IBD, compared with uninflamed areas or tissue from controls. Increased expression of their cognate receptors, CXCR1, CXCR2 and CCR6, was confirmed by quantitative PCR and immunohistochemistry. An identical chemokine response was induced in Caco-2 cells by stimulation with interleukin (IL)-1beta, but not tumour necrosis factor-alpha (TNF-alpha). By contrast, IL-1beta and TNF-alpha were synergistic in an HT29 cell line and primary keratinocytes.

CONCLUSIONS

IL-1beta and TNF-alpha appear to be the pivotal mediators of a previously unidentified coordinated epithelial chemokine response that dominates the mucosal chemokine environment in inflamed IBD tissue.

Investigation of systems to prevent diversion of opiate drugs in general practice in the UK

BACKGROUND

Statutory regulations govern the procedures that must be followed by general practitioners (GPs) in the UK to minimise the risk of diversion of prescribed opiate drugs for illicit use. However, evidence presented at the trial of Harold Shipman, a GP convicted of murdering patients with diamorphine, suggests that the regulations and monitoring of GPs' prescribing are failing.

AIM

To assess the policies followed by general practices in Leicestershire and Rutland with regard to the controlled drugs regulations.

METHODS

A semi-structured interview was administered to a purposeful sample of lead GPs to explore how their practices applied the regulations. The controlled drugs registers and drug storage facilities in these practices were inspected. A questionnaire was sent to all the remaining practices to seek information about their application of the regulations, any concerns they had about the regulations, and any suggestions for improving them.

RESULTS

Of the 142 general practices in Leicestershire, the lead GP in 14 took part in the interviews. Respondents expressed dissatisfaction with current policies including the design of controlled drug registers, and generally supported the reintroduction of an inspection scheme. Ninety (70.9%) of the 127 practices to whom the questionnaire was sent responded and, of these, 31 (34.4%) no longer held a supply of controlled drugs. Those that did hold controlled drugs indicated concern about the regulations, confusion about some aspects including the return and disposal of unused drugs, and a desire for advice and support in the implementation of the regulations. Forty two of the 59 respondents who held a supply of controlled drugs (71.2%) would welcome regular inspection.

CONCLUSION

GPs are confused about the controlled drugs regulations and have little support in implementing them. The suspension of inspection schemes has reduced the amount of advice and support available to them and, in consequence, the regulations are interpreted differently in different practices. These findings are cause for concern about the risk of diversion of controlled drugs, and illustrate how patient safety systems can decay when they are not maintained.

Cellular immune responses to influenza

Cellular immune responses are believed to play an important role in controlling influenza infection. CD4+ and CD8+ T cell responses are well described and CD8+ immunity is of paramount importance in killing virally infected cells. In the past few years several novel techniques have been devised which allow quantification of antigen-specific cellular immune responses and these will be reviewed briefly. Influenza-specific cellular immunity is elicited following natural infection and several viral proteins have been identified as targets for cellular responses. Cellular immunity is detectable throughout life in most donors but there is clear evidence of impaired cellular immunity in the elderly, a population at particular risk of influenza infection. This finding must be viewed against the background of 'immune senescence' that is documented with aging. Cellular responses are able to provide heterosubtypic immunity to influenza viral antigens. As such the induction of cellular immune responses is a highly desirable aim of vaccination protocols. Induction of cellular immunity with conventional formalin-inactivated vaccine is poor although some improvement may be derived from novel forms of vaccine delivery such as the use of adjuvanted carriers. Nevertheless, a range of new vaccines is being developed which are more effective in priming cellular responses. Although there is relatively little detail on the nature of the cellular response induced by these agents, they hold out the promise of more effective and durable protection from influenza infection.

HLA class I-minor histocompatibility antigen tetramers select cytotoxic T cells with high avidity to the natural ligand

INTRODUCTION

Cytotoxic T cells specific for the hematopoietic system-restricted minor histocompatibility antigens HA-1 and HA-2 are potential tools for the treatment of relapsed leukemia after minor histocompatibility antigen mismatched bone marrow transplantation. HA-1/HA-2-specific cytotoxic T cells with strong cytotoxic activity against HA-1/HA-2 positive target cells can be generated in vitro using HA-1 and HA-2 peptide-pulsed dendritic cells as antigen presenting cells.

MATERIAL AND METHODS

We used HLA-A2 HA-1/HA-2 tetramers (HA-1(A2)/HA-2(A2) tetramers) to monitor the in vitro generation of HA-1- or HA-2-specific cytotoxic T cells.

RESULTS

We show that the intensity of the tetramer-staining of the HA-1/HA-2-specific cytotoxic T cells strongly correlates with their capability to recognize mHag positive target cells. The bright tetramer-staining cytotoxic T cells lyse target cells expressing the natural ligand. The dim tetramer-staining cytotoxic T cells fail to lyse natural ligand positive target cells and lyse peptide-pulsed target cells only. The frequency of bright tetramer-staining, high avidity minor histocompatibility antigen-specific CTLs increases significantly upon appropriate antigen-specific restimulations.

CONCLUSION

Our results demonstrate that HLA class I-minor histocompatibility antigen tetramers are useful tools for monitoring and selection of high avidity HA-1- and HA-2-specific cytotoxic T cells for adoptive immunotherapy.

Developments in the treatment of post-transplant viral disease

Stem cell transplantation is a potentially curative procedure for many types of haemopoietic malignancy but is associated with a period of intense immunosuppression which may last for 1 to 2 years. During this time new viral infections or reactivation of endogenous, latent virus can lead to a variety of clinical symptoms which, together, make a significant contribution to the morbidity and mortality of the procedure. Improvements in viral detection, prophylaxis and treatment of established disease are helping to minimize the clinical impact of viral disease, but a definitive solution to this problem must await improvements in our ability to reconstitute an effective immune system. Each of the viruses implicated in post-transplant disease has a unique relationship with the host immune system, and there is every hope that improvements in our understanding of viral immunology will be translated into more effective clinical control.

Influenza virus lung infection protects from respiratory syncytial virus-induced immunopathology

The effect of infection history is ignored in most animal models of infectious disease. The attachment protein of respiratory syncytial virus (RSV) induces T helper cell type 2-driven pulmonary eosinophilia in mice similar to that seen in the failed infant vaccinations in the 1960s. We show that previous influenza virus infection of mice: (a) protects against weight loss, illness, and lung eosinophilia; (b) attenuates recruitment of inflammatory cells; and (c) reduces cytokine secretion caused by RSV attachment protein without affecting RSV clearance. This protective effect can be transferred via influenza-immune splenocytes to naive mice and is long lived. Previous immunity to lung infection clearly plays an important and underestimated role in subsequent vaccination and infection. The data have important implications for the timing of vaccinations in certain patient groups, and may contribute to variability in disease susceptibility observed in humans.

Sequencing and expression analysis of the serine protease gene cluster located in chromosome 19q13 region

The human kallikrein gene cluster, located in the chromosome band 19q13, contains several tissue-specific serine protease genes including the prostate-specific KLK2, KLK3 and prostase genes. To further characterize the gene cluster, we have mapped, sequenced, and analyzed the genomic sequence from the region. The results of EST database searches and GENSCAN gene prediction analysis reveal 13 serine protease genes and several pseudogenes in the region. Expression analysis by RT-PCR indicates that most of these protease genes are expressed only in a subset of the 35 different normal tissues that have been examined. Several protease genes expressed in skin show higher expression levels in psoriatic lesion samples than in non-lesional skin samples from the same patient. This suggests that the imbalance of a complex protease cascade in skin may contribute to the pathology of disease. The proteases, excluding the kallikrein genes, share approximately 40% of their sequences suggesting that the serine protease gene cluster on chromosome 19q13 arose from ancient gene duplications.