254 research outputs found

    Sex versus non-sex versus cheaters

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    Cheating is known to be a potential threat to cooperation. We examine the fitness of a cheater allele in an asexual-haploid versus a sexual-diploid population using three different models. The first model depicts small cooperative groups in which the altruist and cheater are distributed randomly, the second simulates large cooperative groups with varying degrees of spatial aggregation and the third simulates a hymenopteran society with cheater workers. In all the models sex helps stabilize cooperation. The results are not affected by dominance or recessiveness of the cheater allele. In either case, sexual diploidy increases the variance across groups and thus enhances group selection. As a result sex and cooperation can coevolve under conditions when cooperation offers substantial fitness gains and cheaters threaten cooperation. The model predicts that cooperation should be more common in sexually reproducing organisms than asexuals. Among organisms where diploid as well as haploid life-cycle stages are present, cooperation should be seen more commonly in the diploid stage

    Phase 1 clinical trial of CRISPR-engineered CAR19 universal T cells for treatment of children with refractory B cell leukemia

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    Genome editing of allogeneic T cells can provide “off-the-shelf” alternatives to autologous chimeric antigen receptor (CAR) T cell therapies. Disruption of T cell receptor α chain (TRAC) to prevent graft-versus-host disease (GVHD) and removal of CD52 (cluster of differentiation 52) for a survival advantage in the presence of alemtuzumab have previously been investigated using transcription activator–like effector nuclease (TALEN)-mediated knockout. Here, we deployed next-generation CRISPR-Cas9 editing and linked CAR expression to multiplexed DNA editing of TRAC and CD52 through incorporation of self-duplicating CRISPR guide RNA expression cassettes within the 3’ long terminal repeat of a CAR19 lentiviral vector. Three cell banks of TT52CAR19 T cells were generated and cryopreserved. A phase 1, open-label, non-randomized clinical trial was conducted and treated six children with relapsed/refractory CD19-positive B cell acute lymphoblastic leukemia (B-ALL) (NCT04557436). Lymphodepletion included fludarabine, cyclophosphamide, and alemtuzumab and was followed by a single infusion of 0.8 × 10^{6} to 2.0 × 10^{6} CAR19 T cells per kilogram with no immediate toxicities. Four of six patients infused with TT52CAR19 T cells exhibited cell expansion, achieved flow cytometric remission, and then proceeded to receive allogeneic stem cell transplantation. Two patients required biological intervention for grade II cytokine release syndrome, one patient developed transient grade IV neurotoxicity, and one patient developed skin GVHD, which resolved after transplant conditioning. Other complications were within expectations, and primary safety objectives were met. This study provides a demonstration of the feasibility, safety, and therapeutic potential of CRISPR-engineered immunotherapy

    Estimation of stature from the foot and its segments in a sub-adult female population of North India

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    <p>Abstract</p> <p>Background</p> <p>Establishing personal identity is one of the main concerns in forensic investigations. Estimation of stature forms a basic domain of the investigation process in unknown and co-mingled human remains in forensic anthropology case work. The objective of the present study was to set up standards for estimation of stature from the foot and its segments in a sub-adult female population.</p> <p>Methods</p> <p>The sample for the study constituted 149 young females from the Northern part of India. The participants were aged between 13 and 18 years. Besides stature, seven anthropometric measurements that included length of the foot from each toe (T1, T2, T3, T4, and T5 respectively), foot breadth at ball (BBAL) and foot breadth at heel (BHEL) were measured on both feet in each participant using standard methods and techniques.</p> <p>Results</p> <p>The results indicated that statistically significant differences (p < 0.05) between left and right feet occur in both the foot breadth measurements (BBAL and BHEL). Foot length measurements (T1 to T5 lengths) did not show any statistically significant bilateral asymmetry. The correlation between stature and all the foot measurements was found to be positive and statistically significant (<it>p-value </it>< 0.001). Linear regression models and multiple regression models were derived for estimation of stature from the measurements of the foot. The present study indicates that anthropometric measurements of foot and its segments are valuable in the estimation of stature. Foot length measurements estimate stature with greater accuracy when compared to foot breadth measurements.</p> <p>Conclusions</p> <p>The present study concluded that foot measurements have a strong relationship with stature in the sub-adult female population of North India. Hence, the stature of an individual can be successfully estimated from the foot and its segments using different regression models derived in the study. The regression models derived in the study may be applied successfully for the estimation of stature in sub-adult females, whenever foot remains are brought for forensic examination. Stepwise multiple regression models tend to estimate stature more accurately than linear regression models in female sub-adults.</p

    Reduced-Intensity/Reduced-Toxicity Conditioning Approaches Are Tolerated in XIAP Deficiency but Patients Fare Poorly with Acute GVHD

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    X-linked inhibitor of apoptosis (XIAP) deficiency is an inherited primary immunodeficiency characterized by chronic inflammasome overactivity and associated with hemophagocytic lymphohistiocytosis (HLH) and inflammatory bowel disease (IBD). Allogeneic hematopoietic cell transplantation (HCT) with fully myeloablative conditioning may be curative but has been associated with poor outcomes. Reports of reduced-intensity conditioning (RIC) and reduced-toxicity conditioning (RTC) regimens suggest these approaches are well tolerated, but outcomes are not well established. Retrospective data were collected from an international cohort of 40 patients with XIAP deficiency who underwent HCT with RIC or RTC. Thirty-three (83%) patients had a history of HLH, and thirteen (33%) patients had IBD. Median age at HCT was 6.5 years. Grafts were from HLA-matched (n = 30, 75%) and HLA-mismatched (n = 10, 25%) donors. There were no cases of primary graft failure. Two (5%) patients experienced secondary graft failure, and three (8%) patients ultimately received a second HCT. Nine (23%) patients developed grade II-IV acute GVHD, and 3 (8%) developed extensive chronic GVHD. The estimated 2-year overall and event-free survival rates were 74% (CI 55-86%) and 64% (CI 46-77%), respectively. Recipient and donor HLA mismatch and grade II-IV acute GVHD were negatively associated with survival on multivariate analysis with hazard ratios of 5.8 (CI 1.5-23.3, p = 0.01) and 8.2 (CI 2.1-32.7, p < 0.01), respectively. These data suggest that XIAP patients tolerate RIC and RTC with survival rates similar to HCT of other genetic HLH disorders. Every effort should be made to prevent acute GVHD in XIAP-deficient patients who undergo allogeneic HCT

    T-replete cord transplants give superior outcomes in high risk and relapsed/refractory paediatric myeloid malignancy

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    Stem cell transplant (SCT) outcomes in high-risk (HR) and relapsed/refractory (R/R) paediatric acute myeloid leukaemia (AML) and myelodysplastic syndrome (MDS) have been poor historically. Cord blood allows T-cell replete transplant (TRCB), enabling enhanced graft-versus-leukaemia. We collected data from 367 consecutive patients undergoing TRCB (112 patients) or other cell source (255 patients) SCT for paediatric AML/MDS in the UK and Ireland between January 2014 and December 2021. Data was collected about patient's demographics, disease and its treatment including previous transplant, measurable residual disease (MRD) status at transplant, HLA-match, relapse, death, graft versus host disease (GvHD) and transplant-related mortality (TRM). Univariable and multivariable analyses were undertaken. There was a higher incidence of poor prognosis features in the TRCB cohort: 51.4% patients were MRD positive at transplant, 46.4% had refractory disease and 21.4% had relapsed after a previous SCT, compared with 26.1%, 8.6% and 5.1% respectively in the comparator group (all p <0.001). Within the TRCB cohort, Event Free Survival (EFS) was 64.1%, 50% in MRD positive patients and 79% in MRD negative (p= 0.009). To allow for the imbalance in baseline characteristics, a multivariable analysis was performed: the TRCB cohort had significantly improved EFS (0.57[0.35-0.91], p=0.019), time to relapse (0.46[0.26-0.81), p=0.008), and reduced chronic GVHD (HR 0.28 [95% CI 0.11-0.70]; p=0.007), with some evidence of improved Overall Survival (OS) (0.65[0.39-1.07], p = 0.088). The effect appeared similar regardless of MRD status, (interaction p-value= 0.29). CB transplant without serotherapy may be the optimal transplant option for children with myeloid malignancy

    Using Whole Genome Sequences to Investigate Adenovirus Outbreaks in a Hematopoietic Stem Cell Transplant Unit

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    A recent surge in human mastadenovirus (HAdV) cases, including five deaths, amongst a haematopoietic stem cell transplant population led us to use whole genome sequencing (WGS) to investigate. We compared sequences from 37 patients collected over a 20-month period with sequences from GenBank and our own database of HAdVs. Maximum likelihood trees and pairwise differences were used to evaluate genotypic relationships, paired with the epidemiological data from routine infection prevention and control (IPC) records and hospital activity data. During this time period, two formal outbreaks had been declared by IPC, while WGS detected nine monophyletic clusters, seven were corroborated by epidemiological evidence and by comparison of single-nucleotide polymorphisms. One of the formal outbreaks was confirmed, and the other was not. Of the five HAdV-associated deaths, three were unlinked and the remaining two considered the source of transmission. Mixed infection was frequent (10%), providing a sentinel source of recombination and superinfection. Immunosuppressed patients harboring a high rate of HAdV positivity require comprehensive surveillance. As a consequence of these findings, HAdV WGS is being incorporated routinely into clinical practice to influence IPC policy contemporaneously

    Hematopoietic cell transplantation in severe combined immunodeficiency : The SCETIDE 2006-2014 European cohort

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    Publisher Copyright: © 2021 The AuthorsBackground: Hematopoietic stem cell transplantation (HSCT) represents a curative treatment for patients with severe combined immunodeficiency (SCID), a group of monogenic immune disorders with an otherwise fatal outcome. Objective: We performed a comprehensive multicenter analysis of genotype-specific HSCT outcome, including detailed analysis of immune reconstitution (IR) and the predictive value for clinical outcome. Methods: HSCT outcome was studied in 338 patients with genetically confirmed SCID who underwent transplantation in 2006-2014 and who were registered in the SCETIDE registry. In a representative subgroup of 152 patients, data on IR and long-term clinical outcome were analyzed. Results: Two-year OS was similar with matched family and unrelated donors and better than mismatched donor HSCT (P 0.5 × 10e3/μL at +1 year were identified as independent predictors of favorable clinical and immunologic outcome. Conclusion: Recent advances in HSCT in SCID patients have resulted in improved OS and EFS in all genotypes and donor types. To achieve a favorable long-term outcome, treatment strategies should aim for optimal naive CD4 T lymphocyte regeneration.Peer reviewe

    Human embryonic stem cells: preclinical perspectives

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    Human embryonic stem cells (hESCs) have been extensively discussed in public and scientific communities for their potential in treating diseases and injuries. However, not much has been achieved in turning them into safe therapeutic agents. The hurdles in transforming hESCs to therapies start right with the way these cells are derived and maintained in the laboratory, and goes up-to clinical complications related to need for patient specific cell lines, gender specific aspects, age of the cells, and several post transplantation uncertainties. The different types of cells derived through directed differentiation of hESC and used successfully in animal disease and injury models are described briefly. This review gives a brief outlook on the present and the future of hESC based therapies, and talks about the technological advances required for a safe transition from laboratory to clinic
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