125 research outputs found

    Prime Time for HLA Desensitization: Imlifidase in the Spotlight

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    HLA allosensitization; Desensitization; RejectionAlosensibilización HLA; Desensibilización; RechazoAl·losensibilització HLA; Desensibilització; RebuigIn this issue of Transplant International [7], a French expert transplant group endorsed by different French scientific societies (SFT, FNDT, SFHI), propose a set of clinical, immunological, and therapeutic recommendations on how to implement Imlifidase in clinical transplantation. The authors should be acknowledged for the thorough description of the different recommendations provided in this consensus report, especially considering the relatively low level of evidence currently available in this topic. Even though some recommendations are based on their national allocation policy, most of them may be perfectly generalized to any other transplant system worldwide

    Inhibition of Thrombin Receptor Signaling on alpha-Smooth Muscle Actin(+) CD34(+) Progenitors Leads to Repair After Murine Immune Vascular Injury

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    OBJECTIVE: The goal of this study was to use mice expressing human tissue factor pathway inhibitor (TFPI) on α-smooth muscle actin (α-SMA)(+) cells as recipients of allogeneic aortas to gain insights into the cellular mechanisms of intimal hyperplasia (IH). METHODS AND RESULTS: BALB/c aortas (H-2(d)) transplanted into α-TFPI-transgenic (Tg) mice (H-2(b)) regenerated a quiescent endothelium in contrast to progressive IH seen in C57BL/6 wild-type (WT) mice even though both developed aggressive anti-H-2(d) alloresponses, indicating similar vascular injuries. Adoptively transferred Tg CD34(+) (but not CD34(-)) cells inhibited IH in WT recipients, indicating the phenotype of α-TFPI-Tg mice was due to these cells. Compared with syngeneic controls, endogenous CD34(+) cells were mobilized in significant numbers after allogeneic transplantation, the majority showing sustained expression of tissue factor and protease-activated receptor-1 (PAR-1). In WT, most were CD45(+) myeloid progenitors coexpressing CD31, vascular endothelial growth factor receptor-2 and E-selectin; 10% of these cells coexpressed α-SMA and were recruited to the neointima. In contrast, the α-SMA(+) human TFPI(+) CD34(+) cells recruited in Tg recipients were from a CD45(-) lineage. WT CD34(+) cells incubated with a PAR-1 antagonist or taken from PAR-1-deficient mice inhibited IH as Tg cells did. CONCLUSIONS: Specific inhibition of thrombin generation or PAR-1 signaling on α-SMA(+) CD34(+) cells inhibits IH and promotes regenerative repair despite ongoing immune-mediated damage

    Preventing kidney transplant failure by screening for antibodies against human leucocyte antigens followed by optimised immunosuppression: OuTSMART RCT

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    Design: Investigator-led, prospective, open-labelled marker-based strategy (hybrid) randomised trial. Background: Allografts in 3% of kidney transplant patients fail annually. Development of antibodies against human leucocyte antigens is a validated predictive biomarker of allograft failure. Under immunosuppression is recognised to contribute, but whether increasing immunosuppression can prevent allograft failure in human leucocyte antigen Ab+ patients is unclear. Participants: Renal transplant recipients > 1 year post-transplantation attending 13 United Kingdom transplant clinics, without specific exclusion criteria. Interventions: Regular screening for human leucocyte antigen antibodies followed, in positive patients by interview and tailored optimisation of immunosuppression to tacrolimus, mycophenolate mofetil and prednisolone. Objective: To determine if optimisation of immunosuppression in human leucocyte antigen Ab+ patients can cost-effectively prevent kidney allograft failure. Outcome: Time to graft failure after 43 months follow-up in patients receiving the intervention, compared to controls, managed by standard of care. Costs and quality-adjusted life-years were used in the cost-effectiveness analysis. Randomisation and blinding: Random allocation (1 : 1) to unblinded biomarker-led care or double-blinded standard of care stratified by human leucocyte antigen antibodies status (positive/negative) and in positives, presence of donor-specific antibodies (human leucocyte antigen antibodies against donor human leucocyte antigen) or not (human leucocyte antigen antibodies against non-donor human leucocyte antigen), baseline immunosuppression and transplant centre. Biomaker-led care human leucocyte antigen Ab+ patients received intervention. Human leucocyte antigen Ab-negative patients were screened every 8 months. Recruitment Began September 2013 and for 37 months. The primary endpoint, scheduled for June 2020, was moved to March 2020 because of COVID-19. Numbers randomised: From 5519 screened, 2037 were randomised (1028 biomaker-led care, 1009 to standard of care) including 198 with human leucocyte antigen antibodies against donor human leucocyte antigen (106 biomaker-led care, 92 standard of care) and 818 with human leucocyte antigens antibodies against non-donor human leucocyte antigen (427 biomaker-led care, 391 standard of care). Numbers analysed: Two patients were randomised in error so 2035 were included in the intention-to-treat analysis. Outcome: The trial had 80% power to detect a hazard ratio of 0.49 in biomarker-led care DSA+ group, > 90% power to detect hazard ratio of 0.35 in biomarker-led care non-DSA+ group (with 5% type 1 error). Actual hazard ratios for graft failure in these biomarker-led care groups were 1.54 (95% CI: 0.72 to 3.30) and 0.97 (0.54 to 1.74), respectively. There was 90% power to demonstrate non-inferiority of overall biomarker-led care group with assumed hazard ratio of 1.4: This was not demonstrated as the upper confidence limit for graft failure exceeded 1.4: (1.02, 95% CI 0.72 to 1.44). The hazard ratio for biopsy-proven rejection in the overall biomarker-led care group was 0.5 [95% CI: 0.27 to 0.94: p = 0.03]. The screening approach was not cost-effective in terms of cost per quality-adjusted life-year. Harms: No significant differences in other secondary endpoints or adverse events. Limitations: Tailored interventions meant optimisation was not possible in some patients. We did not study pathology on protocol transplant biopsies in DSA+ patients. Conclusions: No evidence that optimised immunosuppression in human leucocyte antigen Ab+ patients delays renal transplant failure. Informing patients of their human leucocyte antigen antibodies status appears to reduce graft rejection. Future work: We need a better understanding of the pathophysiology of transplant failure to allow rational development of effective therapies. Trial registration: This trial is registered as EudraCT (2012-004308-36) and ISRCTN (46157828). Funding: This project was funded by the National Institute for Health and Care Research (NIHR) Efficacy and Mechanism Evaluation programme (11/100/34) and will be published in full in Efficacy and Mechanism Evaluation; Vol. 10, No. 5. See the NIHR Journals Library website for further project information

    C3d‐positive donor‐specific antibodies have a role in pretransplant risk stratification of cross‐match‐positive HLA‐incompatible renal transplantation : United Kingdom multicentre study

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    Anti‐HLA‐antibody characteristics aid to risk‐stratify patients and improve long‐term renal graft outcomes. Complement activation by donor‐specific antibody (DSA) is an important characteristic that may determine renal allograft outcome. There is heterogeneity in graft outcomes within the moderate to high immunological risk cases (cross‐match‐positive). We explored the role of C3d‐positive DSAs in sub‐stratification of cross‐match‐positive cases and relate to the graft outcomes. We investigated 139 cross‐match‐positive living‐donor renal transplant recipients from four transplant centres in the United Kingdom. C3d assay was performed on serum samples obtained at pretreatment (predesensitization) and Day 14 post‐transplant. C3d‐positive DSAs were found in 52 (37%) patients at pretreatment and in 37 (27%) patients at Day 14 post‐transplant. Median follow‐up of patients was 48 months (IQR 20.47–77.57). In the multivariable analysis, pretreatment C3d‐positive DSA was independently associated with reduced overall graft survival, the hazard ratio of 3.29 (95% CI 1.37–7.86). The relative risk of death‐censored five‐year graft failure was 2.83 (95% CI 1.56–5.13). Patients with both pretreatment and Day 14 C3d‐positive DSAs had the worst five‐year graft survival at 45.5% compared with 87.2% in both pretreatment and Day 14 C3d‐negative DSA patients with the relative risk of death‐censored five‐year graft failure was 4.26 (95% CI 1.79, 10.09). In this multicentre study, we have demonstrated for the first time the utility of C3d analysis as a distinctive biomarker to sub‐stratify the risk of poor graft outcome in cross‐match‐positive living‐donor renal transplantation

    Determinants of survival in very low birth weight neonates in a public sector hospital in Johannesburg

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    <p>Abstract</p> <p>Background</p> <p>Audit of disease and mortality patterns provides essential information for health budgeting and planning, as well as a benchmark for comparison. Neonatal mortality accounts for about 1/3 of deaths < 5 years of age and very low birth weight (VLBW) mortality for approximately 1/3 of neonatal mortality. Intervention programs must be based on reliable statistics applicable to the local setting; First World data cannot be used in a Third World setting. Many neonatal units participate in the Vermont Oxford Network (VON); limited resources prevent a significant number of large neonatal units from developing countries taking part, hence data from such units is lacking. The purpose of this study was to provide reliable, recent statistics relevant to a developing African country, useful for guiding neonatal interventions in that setting.</p> <p>Methods</p> <p>This was a retrospective chart review of 474 VLBW infants admitted within 24 hours of birth, between 1 July 2006 and 30 June 2007, to the neonatal unit of Charlotte Maxeke Johannesburg Academic Hospital (CMJAH) in Johannesburg, South Africa. Binary outcome logistic regression on individual variables and multiple logistic regression was done to identify those factors determining survival.</p> <p>Results</p> <p>Overall survival was 70.5%. Survival of infants below 1001 grams birth weight was 34.9% compared to 85.8% for those between 1001 and 1500 grams at birth. The main determinant of survival was birth weight with an adjusted survival odds ratio of 23.44 (95% CI: 11.22 - 49.00) for babies weighing between 1001 and 1500 grams compared to those weighing below 1001 grams. Other predictors of survival were gender (OR 3. 21; 95% CI 1.6 - 6.3), birth before arrival at the hospital (BBA) (OR 0.23; 95% CI: 0.08 - 0.69), necrotising enterocolitis (NEC) (OR 0.06; 95% CI: 0.02 - 0.20), hypotension (OR 0.05; 95% CI 0.01 - 0.21) and nasal continuous positive airways pressure (NCPAP) (OR 4.58; 95% CI 1.58 - 13.31).</p> <p>Conclusions</p> <p>Survival rates compare favourably with other developing countries, but can be improved; especially in infants < 1001 grams birth weight. Resources need to be allocated to preventing the birth of VLBW babies outside hospital, early neonatal resuscitation, provision of NCPAP and prevention of NEC.</p

    Optimized immunosuppression to prevent graft failure in renal transplant recipients with HLA antibodies (OuTSMART): a randomised controlled trial

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    Background: 3% of kidney transplant recipients return to dialysis annually upon allograft failure. Development of antibodies (Ab) against human leukocyte antigens (HLA) is a validated prognostic biomarker of allograft failure. We tested whether screening for HLA Ab, combined with an intervention to improve adherence and optimization of immunosuppression could prevent allograft failure. Methods: Prospective, open-labelled randomised biomarker-based strategy (hybrid) trial in 13 UK transplant centres [EudraCT (2012-004308-36) and ISRCTN (46157828)]. Patients were randomly allocated (1:1) to unblinded or double-blinded arms and screened every 8 months. Unblinded HLA Ab+ patients were interviewed to encourage medication adherence and had tailored optimisation of Tacrolimus, Mycophenolate mofetil and Prednisolone. The primary outcome was time to graft failure in an intention to treat analysis. The trial had 80% power to detect a hazard ratio of 0.49 in donor specific antibody (DSA)+ patients. Findings: From 11/9/13 to 27/10/16, 5519 were screened for eligibility and 2037 randomised (1028 to unblinded care and 1009 to double blinded care). We identified 198 with DSA and 818 with non-DSA. Development of DSA, but not non-DSA was predictive of graft failure. HRs for graft failure in unblinded DSA+ and non-DSA+ groups were 1.54 (95% CI: 0.72 to 3.30) and 0.97 (0.54–1.74) respectively, providing no evidence of an intervention effect. Non-inferiority for the overall unblinded versus blinded comparison was not demonstrated as the upper confidence limit of the HR for graft failure exceeded 1.4 (1.02, 95% CI: 0.72 to 1.44). The only secondary endpoint reduced in the unblinded arm was biopsy-proven rejection. Interpretation: Intervention to improve adherence and optimize immunosuppression does not delay failure of renal transplants after development of DSA. Whilst DSA predicts increased risk of allograft failure, novel interventions are needed before screening can be used to direct therapy

    Clinical risk stratification of paediatric renal transplant recipients using C1q and C3d fixing of de novo donor-specific antibodies

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    Introduction: We have previously shown that children who developed de novo donor-specific human leukocyte antigen (HLA) antibodies (DSA) had greater decline in allograft function. We hypothesised that patients with complement-activating DSA would have poorer renal allograft outcomes. Methods: A total of 75 children developed DSA in the original study. The first positive DSA sample was subsequently tested for C1q and C3d fixing. The primary event was defined as 50% reduction from baseline estimated glomerular filtration rate and was analysed using the Kaplan–Meier estimator. Results: Of 65 patients tested, 32 (49%) and 23 (35%) tested positive for C1q and C3d fixing, respectively. Of the 32 C1q-positive (c1q+) patients, 13 (41%) did not show concomitant C3d fixing. The mean fluorescence intensity values of the original immunoglobulin G DSA correlated poorly with complement-fixing positivity (C1q: adjusted R2 0.072; C3d: adjusted R2 0.11; p < 0.05). C1q+ antibodies were associated with acute tubulitis [0.75 ± 0.18 (C1q+) vs. 0.25 ± 0.08 (C1q−) episodes per patient (mean ± standard error of the mean; p < 0.05] but not with worse long-term renal allograft dysfunction (median time to primary event 5.9 (C1q+) vs. 6.4 (C1q−) years; hazard ratio (HR) 0.74; 95% confidence ratio (CI) 0.30–1.81; p = 0.58]. C3d-positive (C3d+) antibodies were associated with positive C4d histological staining [47% (C3d+) vs. 20% (C3d−); p = 0.04] and with significantly worse long-term allograft dysfunction [median time to primary event: 5.6 (C3d+) vs. 6.5 (C3d−) years; HR 0.38; 95% CI 0.15–0.97; p = 0.04]. Conclusion: Assessment of C3d fixing as part of prospective HLA monitoring can potentially aid stratification of patients at the highest risk of long-term renal allograft dysfunction

    From "Infant Hercules" to "Ghost Town":Industrial collapse and social harm on Teesside

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    This article explicates the harms associated with deindustrialization in Teesside in the North East of England in the context of neoliberalism. Drawing on in-depth qualitative interviews (n = 25), the article explores how ongoing industrial collapse, typified by Sahaviriya Steel Industries’ (SSI) closure in 2015, has generated various harms. First, the article examines industrialism’s socioeconomic security and stability. It then explores the negative impact of SSI’s closure in 2015, including a sense of loss and unemployment. Next, it demonstrates how the absence of economic stability produces harmful outcomes, namely insecurity, mental health problems and bleak visions of the future. The article concludes by casting industrial ruination as an impediment to human flourishing; the normal functioning of capitalism represents a “negative motivation to harm” that prevents the stability and security necessary for individual and collective flourishin

    Rare germline copy number variants (CNVs) and breast cancer risk.

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    Funder: CIHRGermline copy number variants (CNVs) are pervasive in the human genome but potential disease associations with rare CNVs have not been comprehensively assessed in large datasets. We analysed rare CNVs in genes and non-coding regions for 86,788 breast cancer cases and 76,122 controls of European ancestry with genome-wide array data. Gene burden tests detected the strongest association for deletions in BRCA1 (P = 3.7E-18). Nine other genes were associated with a p-value < 0.01 including known susceptibility genes CHEK2 (P = 0.0008), ATM (P = 0.002) and BRCA2 (P = 0.008). Outside the known genes we detected associations with p-values < 0.001 for either overall or subtype-specific breast cancer at nine deletion regions and four duplication regions. Three of the deletion regions were in established common susceptibility loci. To the best of our knowledge, this is the first genome-wide analysis of rare CNVs in a large breast cancer case-control dataset. We detected associations with exonic deletions in established breast cancer susceptibility genes. We also detected suggestive associations with non-coding CNVs in known and novel loci with large effects sizes. Larger sample sizes will be required to reach robust levels of statistical significance
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