Integrating microarray-based spatial transcriptomics and single-cell RNA-seq reveals tissue architecture in pancreatic ductal adenocarcinomas

Single-cell RNA sequencing (scRNA-seq) enables the systematic identification of cell populations in a tissue, but characterizing their spatial organization remains challenging. We combine a microarray-based spatial transcriptomics method that reveals spatial patterns of gene expression using an array of spots, each capturing the transcriptomes of multiple adjacent cells, with scRNA-Seq generated from the same sample. To annotate the precise cellular composition of distinct tissue regions, we introduce a method for multimodal intersection analysis. Applying multimodal intersection analysis to primary pancreatic tumors, we find that subpopulations of ductal cells, macrophages, dendritic cells and cancer cells have spatially restricted enrichments, as well as distinct coenrichments with other cell types. Furthermore, we identify colocalization of inflammatory fibroblasts and cancer cells expressing a stress-response gene module. Our approach for mapping the architecture of scRNA-seq-defined subpopulations can be applied to reveal the interactions inherent to complex tissues.

Defining the outcome of immunosuppression withdrawal after liver transplantation

Successful immunosuppression withdrawal should benefit the natural history of organ transplantation patients. To identify the clinical hazards of removing drug treatment and possible characteristics that predict a favorable outcome in long-term liver recipients, immunosuppression was withdrawn completely and the clinicopathological outcome documented in 18 liver recipients. Indication for transplantation, HLA matching, early rejection history, and presence of microchimerism were examined as predictors of outcome. Chimerism was determined by polymerase chain reaction-based examination for donor-specific HLA-DRB1 alleles and Y-gene-specific nucleotide sequences. At 3 years, 5 patients (28%) remained completely off immunosuppression; 12 patients (67%) experienced histological graft changes: acute rejection in 4, portal tract inflammation/hepatitis in 7, and necrosis in 1. Hepatitis B or C viral infections did not account for the nonrejection patterns. Unmasking of systemic disorders occurred. Chimerism, demonstrated in 7 patients (39%), with skin the optimal tissue, was not associated with tolerance. Parameters associated with successful drug withdrawal were transplantation for non-immune-mediated liver disorders, fewer donor-recipient HLA A, B, and DR mismatches, and a low incidence of early rejection. Immunosuppression withdrawal is a feasible option in a proportion of selected liver recipients, but identification of tolerant patients remains imprecise.

How does functional disability in early rheumatoid arthritis (RA) affect patients and their lives? Results of 5 years of follow-up in 732 patients from the Early RA Study (ERAS)

OBJECTIVES

To assess the impact of rheumatoid arthritis (RA) on function and how this affects major aspects of patients' lives.

METHODS

The inception cohort of RA patients was recruited from rheumatology out-patient departments in nine National Health Service (NHS) hospital trusts in England. All consecutive patients with RA of less than 2 yr duration, prior to any second-line (disease-modifying) drug treatment were recruited and followed-up for 5 yr. Standard clinical, laboratory and radiological assessments, and all hospital-based interventions were recorded prospectively at presentation and yearly. The outcome measures were clinical remission and extra-articular features, functional ability [functional grades I-IV and Health Assessment Questionnaire (HAQ)], use of aids, appliances and home adaptations, orthopaedic interventions, and loss of paid work.

RESULTS

A total of 732 patients completed 5 yr of follow-up, of whom 84% received second-line drugs. Sixty-nine (9.4%) had marked functional loss at presentation, compared with normal function in 243 (33%), and by 5 yr these numbers had increased in each group, respectively, to 113 (16%) and 296 (40%). Home adaptations and/or wheelchair use by 5 yr were seen in 74 (10%). Work disability was seen in 27% of those in paid employment at onset. One hundred and seventeen (17%) patients underwent orthopaedic surgery for RA, 55 (8%) for major joint replacements. Marked functional loss at 5 yr was more likely in women [odds ratio (OR) 1.63, 95% confidence interval (CI) 1.04-2.5], patients older than 60 yr (OR 1.94, 95% CI 1.3-2.9), and with HAQ > 1.0 at presentation (OR 4.4, 95% CI 2.8-7.0).

CONCLUSIONS

Clinical profiles of RA patients treated with conventional drug therapy over 5 yr showed that a small proportion of patients (around 16%) do badly functionally and in terms of life events, whereas around 40% do relatively well. The details and exact figures of cumulative disability are likely to be useful to clinicians, health professionals and patients. The rate of progression and outcome in these patients can be compared against future therapies with any disease-modifying claims.

Serum MMP-3 and MMP-1 and progression of joint damage in early rheumatoid arthritis

OBJECTIVE

Expression and activation of matrix metalloproteinases such as MMP-3 (stromelysin-1) and MMP-1 (collagenase-1) are increased in patients with rheumatoid arthritis (RA). Previous negative reports of their value as predictors of joint damage may be due to the lack of a large longitudinal study of early RA patients. This study evaluated their use in assessing early untreated patients with RA and predicting subsequent joint damage.

METHODS

Ninety-eight patients with early untreated RA of less than 12 months duration and 20 normal controls had baseline serum samples tested with a double-antibody enzyme-linked immunosorbent assay for each of MMP-1 and MMP-3. The subsequent changes in Larsen score (DeltaLarsen) and Health Assessment Questionnaire (DeltaHAQ) over the first 12 months were recorded.

RESULTS

Baseline serum levels of MMP-3 and MMP-1 correlated significantly with baseline C-reactive protein (CRP) (r=0.42 and 0.49, P<0.001), DeltaHAQ (r=0.32 and 0.30, P<0.01) and DeltaLarsen (r=0.23 and 0.32, P<0.05) respectively. Analysis of the group of patients with a normal CRP at presentation (n=21) showed correlation of the baseline MMP-3 and MMP-1 with the presence of erosive disease during the first 12 months (r=0.52 and 0.65 respectively, P<0.05). Logistic regression analysis, in the patients who were non-erosive at presentation, showed that the strongest correlation with progression in Larsen score was the baseline MMP-3 level (r=0.30, P=0.01).

CONCLUSIONS

Baseline serum MMP-1 and MMP-3 levels correlate with disease activity and predict functional and radiographic outcome in early untreated RA. They may have a particular value in predicting the progression of erosive disease in patients who are not erosive at presentation.

Identification of a nerve-associated, lung-resident interstitial macrophage subset with distinct localization and immunoregulatory properties

Tissue-resident macrophages are a diverse population of cells that perform specialized functions including sustaining tissue homeostasis and tissue surveillance. Here, we report an interstitial subset of CD169⁺ lung-resident macrophages that are transcriptionally and developmentally distinct from alveolar macrophages (AMs). They are primarily localized around the airways and are found in close proximity to the sympathetic nerves in the bronchovascular bundle. These nerve- and airway-associated macrophages (NAMs) are tissue resident, yolk sac derived, self-renewing, and do not require CCR2⁺ monocytes for development or maintenance. Unlike AMs, the development of NAMs requires CSF1 but not GM-CSF. Bulk population and single-cell transcriptome analysis indicated that NAMs are distinct from other lung-resident macrophage subsets and highly express immunoregulatory genes under steady-state and inflammatory conditions. NAMs proliferated robustly after influenza infection and activation with the TLR3 ligand poly(I:C), and in their absence, the inflammatory response was augmented, resulting in excessive production of inflammatory cytokines and innate immune cell infiltration. Overall, our study provides insights into a distinct subset of airway-associated pulmonary macrophages that function to maintain immune and tissue homeostasis.

Which patients stop working because of rheumatoid arthritis? Results of five years' follow up in 732 patients from the Early RA Study (ERAS)

OBJECTIVES

To assess the occurrence and prognostic factors for the ability to maintain paid work in patients with rheumatoid arthritis (RA).

SETTING

Inception cohort of patients with RA recruited from rheumatology departments in nine NHS Hospital Trusts in England.

PATIENTS

All consecutive patients with RA of less than two years' duration, before any second line (disease modifying) drug treatment, and followed up for five years.

METHODS

Clinical, laboratory, and radiological assessments, and all treatments were recorded prospectively using a standardised format at presentation and yearly.

OUTCOME MEASURES

Changes in, and loss of paid work by five years' follow up.

RESULTS

732 patients completed the five year follow up. 353/721 (49%) were gainfully employed at the onset of RA, 211 (60%) were still working at five years, 104 (29%) stopped because of the disease, and 31 (9%) retired for reasons other than RA. Work disability at five years was more likely in manual workers (odds ratio (OR) 2.3, 95% confidence interval (CI) 1.4 to 3.8) and worse baseline Health Assessment Questionnaire (HAQ>1.5, OR 2.26, 95% CI 1.38 to 3.7). In combination with other baseline variables (erythrocyte sedimentation rate, sex, age of onset, and radiological erosions), employment outcome was predicted in 78% using multivariate analysis.

CONCLUSIONS

Nearly half of the patients with RA were in paid employment at onset, work disability was an adverse outcome for a third of these patients by five years, and manual work and high baseline HAQ were important predictors for this. These details are likely to be useful to clinicians, health professionals, and patients in order to plan medical, orthopaedic, and remedial treatments in early RA. Future disease modifying treatments could be compared with this cohort of patients who were treated with conventional second line drugs.

p16 (CDKN2) is a major deletion target at 9p21 in bladder cancer

The p16 gene has been identified as a candidate tumour suppressor gene at 9p21, a region commonly deleted in bladder cancer. We screened 140 bladder tumours and 16 cell lines for deletions and sequence variants of p16. Eight cell lines showed homozygous deletion of p16 and two had small sequence variations. All 13 tumours with small defined deletions of 9p21, 18/31 (58%) of tumours with monosomy 9 and 9/91 (10%) of tumours with no chromosome 9 loss of heterozygosity had homozygous deletion of p16. No tumour-specific sequence variants were identified. Deletion mapping revealed a nested set of deletions focused on p16. Six deletions involved p16 but not the related and adjacent gene p15 and one tumour had an intragenic deletion of p16. All other deletions involved both p16 and p15. We conclude that p16 represents the major target for deletion at 9p21 in bladder cancer.

Altered Immunity of Laboratory Mice in the Natural Environment Is Associated with Fungal Colonization

Free-living mammals, such as humans and wild mice, display heightened immune activation compared with artificially maintained laboratory mice. These differences are partially attributed to microbial exposure as laboratory mice infected with pathogens exhibit immune profiles more closely resembling that of free-living animals. Here, we examine how colonization by microorganisms within the natural environment contributes to immune system maturation by releasing inbred laboratory mice into an outdoor enclosure. In addition to enhancing differentiation of T cell populations previously associated with pathogen exposure, outdoor release increased circulating granulocytes. However, these "rewilded" mice were not infected by pathogens previously implicated in immune activation. Rather, immune system changes were associated with altered microbiota composition with notable increases in intestinal fungi. Fungi isolated from rewilded mice were sufficient in increasing circulating granulocytes. These findings establish a model to investigate how the natural environment impacts immune development and show that sustained fungal exposure impacts granulocyte numbers.

Does the age of onset of rheumatoid arthritis influence phenotype?: a prospective study of outcome and prognostic factors

OBJECTIVE

To identify factors affecting prognosis in patients with late-onset rheumatoid arthritis (RA).

METHODS

A total of 400 patients with RA fulfilling the American College of Rheumatology criteria for diagnosis were prospectively recruited from two hospital rheumatology centres. Of these patients, 214 had disease onset above age 65 yr (LORA) and 186 below age 65 yr (YORA). Follow-up clinical, functional, laboratory and radiological assessments were compared. The Ritchie articular index (RAI) and joint erosions were used as markers of disease activity and damage, respectively. Disability was assessed using the Stanford Health Assessment Questionnaire (HAQ).

RESULTS

At median follow-up of 3.6 yr, the frequency of joint erosions was similar (YORA, 51.6%; LORA, 54.2%). The remission rate was greater in the LORA group (YORA, 20.4%; LORA, 45.8%, P < 0.01). Factors associated with the development of erosions were: IgM rheumatoid factor (RF) seropositivity [odds ratio (OR) = 4.24, 95% confidence interval (CI) 2.56, 6.94], HLA DR4 (OR = 2.07, 95% CI 1.28, 3.35) and elevated inflammatory markers (OR = 1.81, 95% CI 1.04, 3.14). Continuous steroid use >3 months for the LORA group was associated with increased erosions (OR = 4.09, 95% CI 1.81, 9.27). LORA patients (OR = 2.99, 95% CI 1.77, 5.02) were more likely to go into remission and IgM RF-seropositive patients less likely to go into clinical remission (OR = 0.47, 95% CI 0.28, 0.77). Female patients with a high HAQ score at presentation experienced a poor functional outcome (female OR = 3.01, 95% CI 1.59, 5.68; high HAQ OR = 3.02, 95% CI 1.98, 4.62).

CONCLUSION

LORA can be as damaging as classical RA and joint erosions are often observed at presentation. Being RF seropositive, DR4 positive, and having elevated inflammatory markers at onset, were associated with poor radiological outcome irrespective of age of onset. Being female and having marked disability at presentation were associated with poor functional outcome in both groups. These findings suggest that treatment approaches used in classical YORA should be instituted with equal vigour in patients with LORA.

Mutation of the 9q34 gene TSC1 in sporadic bladder cancer

Deletions involving chromosome 9 occur in more than 50% of human bladder cancers of all grades and stages. Most involve loss of the whole chromosome or of an entire chromosome arm but some small deletions are found which can be used to define critical regions which may contain tumour suppressor genes. We have localized such a critical region of deletion at 9q34 between the markers D9S149 and D9S66, an interval which contains the Tuberous Sclerosis gene TSC1. Single strand conformation polymorphism (SSCP) and sequence analysis of TSC1 in bladder tumours and cell lines with 9q34 loss of heterozygosity (LOH) has identified five mutations in retained TSC1 alleles. Our results support the hypothesis that TSC1 can act as a bladder tumour suppressor gene.

Graft and systemic disease in long-term survivors of liver transplantation

In this clinicopathological study, we have examined the prevalence of biochemical and histological graft abnormalities in 116 patients who have lived for longer than five years since orthotopic liver transplantation (mean, 8.4 years [range, 5.2-19.5 years]). In each patient, the protocol biopsy was carried out in addition to full clinical, biochemical, and immunological evaluation. The renal function was preserved in most patients (mean creatinine, 86 micromol/L [0.95 mg%]) with only 35% showing any degree of impairment, and only one patient with pretransplant renal failure required dialysis. Forty one (35%) of the patients had normal biochemical liver function tests (LFTs); 19 of these patients had histologic abnormalities. Of the remaining 75 patients with abnormal LFTs, 65 were found to have histological abnormalities on liver biopsy. Some of the 84 patients with an abnormal histology had more than one finding but were placed into 6 categories according to the main change as follows: chronic hepatitis in 27; primary biliary cirrhosis-like changes in 8; cholangitis in 15; structural anomalies in 26; chronic rejection in 2; mild acute cellular rejection in 1; and miscellaneous in 5. The recurrence of B, C, or autoimmune hepatitis accounted for 14 cases of chronic hepatitis, whereas, in 13 cases, no cause could be detected. The latter cases included 8 patients who had liver transplants for primary biliary cirrhosis (PBC), leaving suboptimally treated rejection or disease recurrence as possible causes. Characteristic histological features of PBC were observed in 8 additional cases that had liver transplantations for this disease. Of the 26 cases with structural anomalies, various types of occlusive vasculopathy were detected during pre- or posttransplantation in 12 cases. All but one of these were maintained on azathioprine, the only possible etiological factor in the 14 other cases, 5 of whom showed stabilization or clinical and histological improvement following withdrawal of the drug. De-novo malignancy was seen in 3.4% of cases, causing mortality in only one patient to date. This study demonstrates an unexpectedly high prevalence of histological abnormalities that is found often in the presence of normal biochemical liver-function in liver grafts of long-term survivors. Although graft loss at this time is rare, protocol liver biopsies at 5 years, and thereafter at 2-year intervals, may allow for earlier beneficial therapeutic intervention.

Anti-CCP antibodies measured at disease onset help identify seronegative rheumatoid arthritis and predict radiological and functional outcome

OBJECTIVE

Anti-cyclic citrullinated peptide (anti-CCP) antibodies have been identified as highly specific for rheumatoid arthritis (RA). Studies suggest an association with radiographic outcome. The aims of this study were to assess the diagnostic and prognostic utility of the second-generation anti-CCP(2) test in a large cohort of early RA patients compared with connective tissue disease (CTD) controls.

METHODS

One hundred and eighty-two patients with RA and 121 patients with CTD were recruited. All RA patients had less than 24 months of symptoms and had CRP, rheumatoid factor (RF), HLA typing (SE) and anti-CCP(2) antibodies measured at baseline. Function was assessed using the Health Assessment Questionnaire (HAQ) and X-rays performed at 0, 12 and 24 months.

RESULTS

The anti-CCP(2) antibody test demonstrated a specificity of 91% and sensitivity of 81% for RA when compared with controls. In RF-negative patients, specificity was 92% and sensitivity 60%. Baseline demographics of the RA cohort showed mean age 57 yr, mean symptom duration 7 months, 63% RF-positive patients, 72% SE-positive, 81% CCP-positive and 21% erosive. The only predictor of change in Larsen score from 0 to 24 months in the cohort was the presence of the shared epitope (P<0.05) and in the RF-negative subgroup it was CCP(2) antibody titre >100 (P<0.05). Baseline HAQ was the only significant predictor of HAQ at 24 months, but in the RF-negative subgroup CCP(2) antibody titre >100 predicted a poor functional response at 24 months (P<0.05).

CONCLUSIONS

This study confirms the diagnostic utility of anti-CCP(2) antibodies in early RA, particularly in seronegative patients, in whom anti-CCP(2) positivity also conferred prognostic utility for radiographic and functional outcomes.

Increased whole body protein breakdown predominates over increased whole body protein synthesis in multiple organ failure

1. Whole body protein turnover was measured using a primed-constant infusion of L-[1-13C]leucine with measurement of breath 13CO2 production and plasma 13C alpha-ketoisocaproate enrichment. Ten fasting patients, requiring mechanical ventilation and suffering from multiple organ failure, and six healthy control subjects were studied. 2. Protein breakdown and leucine removal from the plasma for protein synthesis were significantly higher in the patients than in the control subjects (P < 0.01). In addition, leucine oxidation was almost 75% higher in the patients than in the healthy control subjects (P < 0.05). 3. Plasma concentrations of glucose, insulin and growth hormone were not different between the two groups, but those of glucagon (not significant), noradrenaline (P < 0.05) and cortisol (P < 0.01) were almost two- and three-fold higher in the patients than in the control subjects. 4. Mean energy expenditure, measured by indirect calorimetry, was 30% higher in the patients than in the healthy control subjects (P < 0.01). 5. Combining the data from both groups of subjects and using multiple regression analysis, cortisol was found to be the most significant predictor of (i) protein breakdown (48% of variance explained), (ii) leucine oxidation (69%) and (iii) hourly energy expenditure (54%). 6. The present investigation using [13C]leucine tracer methods demonstrated, in patients with multiple organ failure, that whole body protein breakdown and synthesis increased concomitantly and were twice as high as rates measured in healthy control subjects. Of the hormones measured in the present study, cortisol appears to have the most significant effect on whole body protein turnover.

Increased weight gain by C-section: Functional significance of the primordial microbiome

Epidemiological evidence supports a direct association between early microbiota impact-including C-section-and obesity. We performed antibiotic-free, fostered C-sections and determined the impact on the early microbiota and body weight during development. Mice in the C-section group gained more body mass after weaning, with a stronger phenotype in females. C-section-born mice lacked the dynamic developmental gut microbiota changes observed in control mice. The results demonstrate a causal relationship between C-section and increased body weight, supporting the involvement of maternal vaginal bacteria in normal metabolic development.

Clinical associations of dual-energy X-ray absorptiometry measurement of hand bone mass in rheumatoid arthritis

Hand bone mineral density (BMD) measurement by dual-energy X-ray absorptiometry (DXA) has potential as a marker of progression in early rheumatoid arthritis (RA). We examined a DXA methodology and studied in a cross-sectional manner 202 patients with RA. Hand BMD correlated inversely with age and was higher in males. Hand BMD correlated with lumbar and femoral sites. In females, BMD of the hand correlated positively with grip strength and negatively with disability. Those with higher C-reactive protein (CRP) had significantly lower hand BMD than those with normal CRP. In patients with a normal CRP, the hand BMD:lumbar BMD ratios were significantly higher in patients with longer disease duration. Hand BMD correlates with measures of disease activity, functional capacity and also with lumbar and femoral BMD. Hand bone loss occurs in early disease, in the absence of detectable systemic disease, and before lumbar BMD loss. It has the potential to be an outcome measure in early disease.

Clinical characteristics affecting the outcome of liver retransplantation

BACKGROUND

The outcome of retransplantation remains unsatisfactory when compared with primary transplantation of the liver. The aim of the present study was to determine which preoperative clinical and laboratory risk variables are implicated in the poorer outcome.

METHODS

The preoperative status of 70 retransplanted patients was compared with a group of 303 time-matched recipients receiving their first graft.

RESULTS

Survival at 1 year was reduced in the retransplant versus the primary transplant group (50% vs. 80%, P<0.001). Preoperatively older age, high United Network of Organ Sharing score, inpatient status, elevated bilirubin, and creatinine levels were associated with increased mortality after a second transplant. Preoperatively, the retransplant group had higher encephalopathy grades, were more likely to be inpatients, and had higher serum creatinine, bilirubin, and white cell levels than the primary recipients (P<0.05 in all cases). The median length of inpatient stay was longer after the second transplant (25 vs. 19 days, P<0.001).

CONCLUSIONS

These factors assist in the stratification of patients awaiting retransplantation; however, the outcome of this procedure is only likely to be improved with an earlier identification of the patients who require it, along with an increased priority in organ allocation.

Distribution of prostaglandins E1,E2, F1-alpha and F2-alpha in some animal tissues

A survey of the distribution of prostaglandins E1, E2, F1α and F2α in fourteen tissues from the dog, cat, rat, rabbit, guinea-pig and chicken has been made. One or more of these prostaglandins are present in varying amounts in most tissues with PGE2 PGF2α occurring most commonly.

Rewilding Nod2 and Atg16l1 Mutant Mice Uncovers Genetic and Environmental Contributions to Microbial Responses and Immune Cell Composition

The relative contributions of genetic and environmental factors to variation in immune responses are poorly understood. Here, we performed a phenotypic analysis of immunological parameters in laboratory mice carrying susceptibility genes implicated in inflammatory bowel disease (IBD) (Nod2 and Atg16l1) upon exposure to environmental microbes. Mice were released into an outdoor enclosure (rewilded) and then profiled for immune responses in the blood and lymph nodes. Variations of immune cell populations were largely driven by the environment, whereas cytokine production elicited by microbial antigens was more affected by the genetic mutations. We identified transcriptional signatures in the lymph nodes associated with differences in T cell populations. Subnetworks associated with responses against Clostridium perfringens, Candida albicans, and Bacteroides vulgatus were also coupled with rewilding. Therefore, exposing laboratory mice with genetic mutations to a natural environment uncovers different contributions to variations in microbial responses and immune cell composition.

N-acetylcysteine improves indocyanine green extraction and oxygen transport during hepatic dysfunction

OBJECTIVES

To investigate whether the beneficial systemic hemodynamic effects of N-acetylcysteine, an agent that increases cyclic guanosine monophosphate (cGMP) concentration in fulminant hepatic failure, are present in a range of liver disorders and what concurrent effect this agent has on the hepatic-splanchnic circulation.

SETTING

Liver Failure Unit, King's College Hospital, London, UK.

PATIENTS

Fifteen patients with hepatic dysfunction who were mechanically ventilated, either after liver transplantation or during an acute or decompensated chronic liver disorder.

INTERVENTIONS

Prostacyclin was administered at a continuous infusion rate of 5 ng/kg/min for 60 mins. After a washout period, the hemodynamic effects of this infusion were compared with the effects present during infusion of N-acetylcysteine at 150 mg/kg in 250 mL of 5% dextrose in water over 15 mins and then 50 mg/kg in 250 mL of 5% dextrose for 45 mins at an infusion rate of 62.5 mL/hr.

MEASUREMENTS AND MAIN RESULTS

Following N-acetylcysteine infusion, the baseline oxygen delivery (DO2) increased from 667 +/- 154 to 751 +/- 166 (SD) mL/min/m2, and oxygen consumption (VO2) improved in 13 of 15 patients (150 +/- 30 to 169 +/- 25 mL/min/m2) (p< .01). Indocyanine green clearance, as determined by a fiberoptic physiologic monitoring system, also improved in 13 of 15 patients (7.3 +/- 4.2% to 11.8 +/- 4.0% [mean change 100%, 95% confidence interval 9 to 256]) (p = .002). Patients who were defined as responders in relation to systemic hemodynamics (VO2 of >10% from baseline [n = 6; 40%]) had a significantly lower baseline consumption compared with that of nonresponders (133 vs. 162 mL/min/m2, p = .04). No clear relationship between the increments in VO2 and indocyanine green clearance was observed (r2 = .21; p = .08). Prostacyclin resulted in moderate improvements in systemic DO2 (but not VO2) and a nonsignificant increase in indocyanine green clearance.

CONCLUSION

N-acetylcysteine increases systemic VO2 in a proportion of patients with a wide variety of hepatic disorders. In addition, N-acetylcysteine elicits an improvement in indocyanine green clearance. These properties may be clinically useful in a range of critical illnesses where systemic or hepatic-splanchnic circulations are compromised.

Association of DRB1 shared epitope genotypes with early mortality in rheumatoid arthritis: results of eighteen years of followup from the early rheumatoid arthritis study

OBJECTIVE

To determine whether the HLA-DRB1 shared epitope (SE) is associated with early mortality and specific causes of death in rheumatoid arthritis (RA).

METHODS

HLA-DRB1 genotyping was carried out on blood samples from 767 patients recruited for the Early RA Study (ERAS), a multicenter, inception cohort study with followup over 18 years. Dates and causes of death (n = 186) were obtained from the Office of National Statistics. The association of HLA-DRB1 alleles with risk of mortality was assessed using Cox proportional hazards regression analyses. Multivariate stepwise models were used to assess the predictive value of HLA-DRB1 genotypes compared with other potential baseline risk factors.

RESULTS

The SE was not significantly associated with overall mortality. However, the presence of 2 SE alleles was associated with risk of mortality from ischemic heart disease (hazard ratio [HR] 2.02 [95% confidence interval 1.04-3.94], P = 0.04), and malignancy (HR 2.18 [95% confidence interval 1.17-4.08], P = 0.01). Analysis of specific SE genotypes (corrected for age and sex) revealed that the HLA-DRB1*0101/*0401 and 0404/*0404 genotypes were the strongest predictors of mortality from ischemic heart disease (HR 5.11 and HR 7.55, respectively), and DRB1*0101/*0401 showed a possible interaction with smoking. Male sex, erythrocyte sedimentation rate, and Carstairs Deprivation Index were also predictive, but the Health Assessment Questionnaire score, rheumatoid factor, nodules, and swollen joint counts were not. Mortality due to malignancy was particularly associated with DRB1*0101 genotypes.

CONCLUSION

The risk of mortality due to ischemic heart disease or cancer in RA is increased in patients carrying HLA-DRB1 genotypes with particular homozygous and compound heterozygous SE combinations.

Transmission of donor melanoma to multiple organ transplant recipients

Malignant melanoma represents the most common tumour responsible for donor-derived post transplantation malignancies. We report the varied presentation and outcome of three graft recipients (two kidney and hepatic) who developed metastatic melanoma following cadaveric organ transplantation from a single multiorgan donor. Two of the recipients presented with symptomatic metastatic lesions and the third patient, despite being carefully monitored, developed evidence of metastatic cutaneous melanoma. Two of the patients died as a direct result of their melanomas. The recipients of corneal and cardiac grafts remain disease-free. We conclude that despite careful screening, donor-derived tumours remain a not uncommon clinical entity. The identification of a lesion in one recipient should prompt immediate examination and investigation of the remaining recipients of multiorgan donations.

Tolerance and latent cellular rejection in long-term liver transplant recipients

Tolerance develops in a proportion of long-term liver transplant recipients but currently cannot be identified before an attempt at withdrawal from immunosuppression therapy. In the present study, we have examined the immunophenotypic characteristics of the cellular infiltrate in portal tracts and lobules as observed in liver biopsy specimens in relation to the outcome of subsequent withdrawal from immunosuppression therapy. Cryostat biopsy specimens from 27 long-term recipients before drug withdrawal, and from 10 patients with recent transplants who were having acute rejection, were analyzed. Immunohistochemical staining was performed for CD3+ (pan T cell), CD8+ (cytotoxic), CD4+ (helper), CD45RO+ (memory), CD45RA+ (naive), CD56+ (natural killer), CD68+ (macrophage), and CD8+ perforin+ cells. Fewer CD8+ and CD3+ cells were present in the lobular areas of biopsy specimens from patients who were successfully withdrawn from immunosuppression therapy (n = 6) compared with biopsy specimens from patients with nontolerant grafts (n = 9; 15 vs. 23 cells/high-power field [hpf] [P < .01] and 16 vs. 26 cells/hpf [P < .03], respectively) or biopsy specimens obtained during acute rejection (15 vs. 31 cells/hpf [P < .01] and 16 vs. 32 cells/hpf [P < .01]). Cell frequencies in the biopsy specimens of nontolerant long-term patients were similar to those found with acute rejection. Immunophenotyping the lobular inflammation within long-term liver allografts assists in identifying those patients in whom drug withdrawal is likely to be unsuccessful and in whom it is postulated a form of inactive, latent cellular rejection exists.

Assessment of potential donors for living related liver transplantation

BACKGROUND

Living related liver transplantation has been developed as an important potential source of organs for treatment of children with acute and chronic liver disease. A single UK centre performing living related liver transplantation was established in 1993.

METHODS

Parents who were potential donors for their children for living related liver transplantation were assessed for suitability according to a protocol based on one developed and published by the University of Chicago Transplant Group. Records kept by the transplant coordinators were retrieved and data were extracted.

RESULTS

Of 64 potential donors for 32 potential recipients ten were excluded at a preliminary stage. Fourteen ultimately became donors. Of 54 parents who began evaluation 23 were finally considered to be suitable. There were 19 non-disease-related reasons for unsuitability: blood group mismatch (eight cases), size discrepancy (six), pregnancy (two), oral contraceptive medication (one), vascular anatomy variant (one) and age (one). Sixteen were unsuitable because disease was found, namely fatty liver (four), thyroid disease (two), hepatitis B positivity (two), cardiac murmur (one), anaemia (one), glucose-6-phosphate dehydrogenase deficiency (one), diabetes mellitus (one) and psychological problems (one), and three parents were affected by the same disorder as the child (Alagille syndrome, one; mitochondrial disorder, one; recurrent cholestasis, one). Three parents were rejected for more than one reason. Both parents were unsuitable for donation in 21 per cent of cases.

CONCLUSION

Parents approach living related liver transplantation with enthusiasm. They should be advised of the high chance of unsuitability, including the finding of significant pathology. The limitation of living related liver transplantation as the major source of organs for children is recognized.