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1.
iScience ; 27(6): 110072, 2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38883813

ABSTRACT

The intestine is vulnerable to chemotherapy-induced damage due to the high rate of intestinal epithelial cell (IEC) proliferation. We have developed a human intestinal organoid-based 3D model system to study the direct effect of chemotherapy-induced IEC damage on T cell behavior. Exposure of intestinal organoids to busulfan, fludarabine, and clofarabine induced damage-related responses affecting both the capacity to regenerate and transcriptional reprogramming. In ex vivo co-culture assays, prior intestinal organoid damage resulted in increased T cell activation, proliferation, and migration. We identified galectin-9 (Gal-9) as a key molecule released by damaged organoids. The use of anti-Gal-9 blocking antibodies or CRISPR/Cas9-mediated Gal-9 knock-out prevented intestinal organoid damage-induced T cell proliferation, interferon-gamma release, and migration. Increased levels of Gal-9 were found early after HSCT chemotherapeutic conditioning in the plasma of patients who later developed acute GVHD. Taken together, chemotherapy-induced intestinal damage can influence T cell behavior in a Gal-9-dependent manner which may provide novel strategies for therapeutic intervention.

2.
Article in English | MEDLINE | ID: mdl-38363390

ABSTRACT

For children who show strongly deviant behaviour in the Netherlands, a distinction is made between behavioural problems and psychiatric problems. As a result, two different domains have emerged over time, each with its own legal frameworks and inclusion and exclusion criteria. Consequently, there is no well-organized, coherent system for youth mental health care in the Netherlands. This strong dichotomy raises the question whether patients are being admitted to facilities where they are receiving appropriate care. In addition, referral bias can arise, because the type of complaint with which a young person presents is often dependent on the type of coping of the individual and thus, in turn, the gender of the patient. In this Position Paper, we examined the gender distribution at a youth psychiatric high and intensive care (HIC-Y) and other streams of youth care in the Netherlands to explore possible inequities in access to psychiatric care among children and adolescents. Results show that girls are significantly more likely than boys to be admitted to the HIC-Y for suicidal thoughts, self-harm and emotional dysregulation. In fact, girls account for 80% of all admissions, while boys account for only 20%. In contrast, regional and national reports from youth services and probation show a majority of boys being admitted (56-89%). The way care is organized (lack of cross-domain collaboration and the interplay between gender-dependent coping and exclusion criteria) seems to play a role in the underrepresentation of boys in acute psychiatry and their overrepresentation in secure youth care. Based on our research results, the concern is raised whether boys have a greater chance of undertreatment for psychiatric problems. Further research is needed to better understand the underlying factors that contribute to gender bias in psychiatric admissions, and to develop interventions that promote gender equality in healthcare.

3.
Hum Reprod ; 39(2): 275-281, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38099857

ABSTRACT

Infertility is a complex condition affecting millions of couples worldwide. The current definition of infertility, based on clinical criteria, fails to account for the molecular and cellular changes that may occur during the development of infertility. Recent advancements in sequencing technology and single-cell analysis offer new opportunities to gain a deeper understanding of these changes. The endometrium has a potential role in infertility and has been extensively studied to identify gene expression profiles associated with (impaired) endometrial receptivity. However, limited overlap among studies hampers the identification of relevant downstream pathways that could play a role in the development of endometrial-related infertility. To address these challenges, we propose sequencing the endometrial transcriptome of healthy and infertile women at the single-cell level to consistently identify molecular signatures. Establishing consensus on physiological patterns in endometrial samples can aid in identifying deviations in infertile patients. A similar strategy has been used with great success in cancer research. However, large collaborative initiatives, international uniform protocols of sample collection and processing are crucial to ensure reliability and reproducibility. Overall, the proposed approach holds promise for an objective and accurate classification of endometrial-based infertility and has the potential to improve diagnosis and treatment outcomes.


Subject(s)
Infertility, Female , Female , Humans , Infertility, Female/diagnosis , Infertility, Female/genetics , Infertility, Female/metabolism , Reproducibility of Results , Endometrium/metabolism , Transcriptome , Treatment Outcome , Embryo Implantation/physiology
4.
Ann Surg Open ; 4(3): e334, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37746594

ABSTRACT

Objective: We aim to investigate the effects of genetically based HLA matching on patient and graft survival, and acute and chronic rejection after liver transplantation. Background: Liver transplantation is a common treatment for patients with end-stage liver disease. In contrast to most other solid organ transplantations, there is no conclusive evidence supporting human leukocyte antigen (HLA) matching for liver transplantations. With emerging alternatives such as transplantation of bankable (stem) cells, HLA matching becomes feasible, which may decrease the need for immunosuppressive therapy and improve transplantation outcomes. Methods: We systematically searched the PubMed, Embase, and Cochrane databases and performed a meta-analysis investigating the effect of genetic HLA matching on liver transplantation outcomes (acute/chronic rejection, graft failure, and mortality). Results: We included 14 studies with 2682 patients. HLA-C mismatching significantly increased the risk of acute rejection (full mismatching: risk ratio = 1.90, 95% confidence interval = 1.08 to 3.33, P = 0.03; partial mismatching: risk ratio = 1.33, 95% confidence interval = 1.07 to 1.66, P = 0.01). We did not discern any significant effect of HLA mismatching per locus on acute rejection for HLA-A, -B, -DR, and -DQ, nor on chronic rejection, graft failure, or mortality for HLA-DR, and -DQ. Conclusions: We found evidence that genetic HLA-C matching reduces the risk of acute rejection after liver transplantation while matching for other loci does not reduce the risk of acute rejection, chronic rejection, graft failure, or mortality.

5.
Front Oncol ; 13: 1192806, 2023.
Article in English | MEDLINE | ID: mdl-37503310

ABSTRACT

Background: Pediatric oncology patients who require admission to the pediatric intensive care unit (PICU) have worse outcomes compared to their non-cancer peers. Although multi-organ dysfunction (MOD) plays a pivotal role in PICU mortality and morbidity, risk factors for MOD have not yet been identified. We aimed to identify risk factors at PICU admission for new or progressive MOD (NPMOD) during the first week of PICU stay. Methods: This retrospective cohort study included all pediatric oncology patients aged 0 to 18 years admitted to the PICU between June 2018 and June 2021. We used the recently published PODIUM criteria for defining multi-organ dysfunction and estimated the association between covariates at PICU baseline and the outcome NPMOD using a multivariable logistic regression model, with PICU admission as unit of study. To study the predictive performance, the model was internally validated by using bootstrap. Results: A total of 761 PICU admissions of 571 patients were included. NPMOD was present in 154 PICU admissions (20%). Patients with NPMOD had a high mortality compared to patients without NPMOD, 14% and 1.0% respectively. Hemato-oncological diagnosis, number of failing organs and unplanned admission were independent risk factors for NPMOD. The prognostic model had an overall good discrimination and calibration. Conclusion: The risk factors at PICU admission for NPMOD may help to identify patients who may benefit from closer monitoring and early interventions. When applying the PODIUM criteria, we found some opportunities for fine-tuning these criteria for pediatric oncology patients, that need to be validated in future studies.

6.
bioRxiv ; 2023 Apr 30.
Article in English | MEDLINE | ID: mdl-37163028

ABSTRACT

The intestine is vulnerable to chemotherapy-induced toxicity due to its high epithelial proliferative rate, making gut toxicity an off-target effect in several cancer treatments, including conditioning regimens for allogeneic hematopoietic cell transplantation (allo-HCT). In allo-HCT, intestinal damage is an important factor in the development of Graft-versus-Host Disease (GVHD), an immune complication in which donor immune cells attack the recipient's tissues. Here, we developed a novel human intestinal organoid-based 3D model system to study the direct effect of chemotherapy-induced intestinal epithelial damage on T cell behavior. Chemotherapy treatment using busulfan, fludarabine, and clofarabine led to damage responses in organoids resulting in increased T cell migration, activation, and proliferation in ex- vivo co-culture assays. We identified galectin-9 (Gal-9), a beta-galactoside-binding lectin released by damaged organoids, as a key molecule mediating T cell responses to damage. Increased levels of Gal-9 were also found in the plasma of allo-HCT patients who later developed acute GVHD, supporting the predictive value of the model system in the clinical setting. This study highlights the potential contribution of chemotherapy-induced epithelial damage to the pathogenesis of intestinal GVHD through direct effects on T cell activation and trafficking promoted by galectin-9.

7.
Brain Commun ; 5(1): fcac324, 2023.
Article in English | MEDLINE | ID: mdl-36632180

ABSTRACT

Hereditary proximal spinal muscular atrophy causes weakness and increased fatigability of repetitive motor functions. The neuromuscular junction is anatomically and functionally abnormal in patients with spinal muscular atrophy. Pharmacological improvement of neuromuscular transmission may therefore represent a promising additional treatment strategy. We conducted a Phase II, monocentre, placebo-controlled, double-blind, cross-over trial with the acetylcholinesterase inhibitor pyridostigmine in treatment-naïve patients with spinal muscular atrophy types 2-4. We investigated the safety and efficacy of pyridostigmine on fatigability and motor function. Each participant received pyridostigmine and a placebo for 8 weeks, in random order. Primary outcomes were the repeated nine-hole peg test for fatigability and motor function measure. Secondary outcomes were patient-reported effects, endurance shuttle test combined scores and adverse events. We included 35 patients. For the repeated nine-hole peg test, the mean difference was 0.17 s/trial (95% confidence interval: -1.17-1.49; P = 0.8), favouring placebo, and for the motor function measure, 0.74% (95% confidence interval: 0.00-1.49; P = 0.05), favouring pyridostigmine. Around 74% of patients reported medium-to-large beneficial effects of pyridostigmine on fatigability, compared with 29.7% in the placebo arm. This was paralleled by a reduced dropout risk of 70% on the endurance shuttle test combined scores (hazard ratio: 0.30; 95% confidence interval: 0.15-0.58) under pyridostigmine. Adverse events, mostly mild and self-limiting, occurred more frequently under pyridostigmine. No serious adverse events related to the study medication were observed. Patients with spinal muscular atrophy tolerated pyridostigmine well. There were no significant differences in primary outcomes, but the self-reported reduction of fatigability and improved endurance shuttle test combined score performance suggest that pyridostigmine may be useful as an additional therapy to survival motor neuron-augmenting drugs. Trial registration number: EudraCT: 2011-004369-34, NCT02941328.

8.
Am J Hum Genet ; 110(1): 146-160, 2023 01 05.
Article in English | MEDLINE | ID: mdl-36608681

ABSTRACT

Neddylation has been implicated in various cellular pathways and in the pathophysiology of numerous diseases. We identified four individuals with bi-allelic variants in NAE1, which encodes the neddylation E1 enzyme. Pathogenicity was supported by decreased NAE1 abundance and overlapping clinical and cellular phenotypes. To delineate how cellular consequences of NAE1 deficiency would lead to the clinical phenotype, we focused primarily on the rarest phenotypic features, based on the assumption that these would best reflect the pathophysiology at stake. Two of the rarest features, neuronal loss and lymphopenia worsening during infections, suggest that NAE1 is required during cellular stress caused by infections to protect against cell death. In support, we found that stressing the proteasome system with MG132-requiring upregulation of neddylation to restore proteasomal function and proteasomal stress-led to increased cell death in fibroblasts of individuals with NAE1 genetic variants. Additionally, we found decreased lymphocyte counts after CD3/CD28 stimulation and decreased NF-κB translocation in individuals with NAE1 variants. The rarest phenotypic feature-delayed closure of the ischiopubic rami-correlated with significant downregulation of RUN2X and SOX9 expression in transcriptomic data of fibroblasts. Both genes are involved in the pathophysiology of ischiopubic hypoplasia. Thus, we show that NAE1 plays a major role in (skeletal) development and cellular homeostasis during stress. Our approach suggests that a focus on rare phenotypic features is able to provide significant pathophysiological insights in diseases caused by mutations in genes with pleiotropic effects.


Subject(s)
Intellectual Disability , Lymphopenia , Humans , NEDD8 Protein/genetics , NEDD8 Protein/metabolism , Signal Transduction/genetics , Intellectual Disability/genetics , NF-kappa B/metabolism , Proteasome Endopeptidase Complex/metabolism , Lymphopenia/genetics
9.
Pediatr Blood Cancer ; 70(1): e30036, 2023 01.
Article in English | MEDLINE | ID: mdl-36316817

ABSTRACT

BACKGROUND: Hospitalized pediatric oncology patients are at risk of severe clinical deterioration. Yet Pediatric Early Warning System (PEWS) scores have not been prospectively validated in these patients. We aimed to determine the predictive performance of the modified BedsidePEWS score for unplanned pediatric intensive care unit (PICU) admission and cardiopulmonary resuscitation (CPR) in this patient population. METHODS: We performed a prospective cohort study in an 80-bed pediatric oncology hospital in the Netherlands, where care has been nationally centralized. All hospitalized pediatric oncology patients aged 0-18 years were eligible for inclusion. A Cox proportional hazard model was estimated to study the association between BedsidePEWS score and unplanned PICU admissions or CPR. The predictive performance of the model was internally validated by bootstrapping. RESULTS: A total of 1137 patients were included. During the study, 103 patients experienced 127 unplanned PICU admissions and three CPRs. The hazard ratio for unplanned PICU admission or CPR was 1.65 (95% confidence interval [CI]: 1.59-1.72) for each point increase in the modified BedsidePEWS score. The discriminative ability was moderate (D-index close to 0 and a C-index of 0.83 [95% CI: 0.79-0.90]). Positive and negative predictive values of modified BedsidePEWS score at the widely used cutoff of 8, at which escalation of care is required, were 1.4% and 99.9%, respectively. CONCLUSION: The modified BedsidePEWS score is significantly associated with requirement of PICU transfer or CPR. In pediatric oncology patients, this PEWS score may aid in clinical decision-making for timing of PICU transfer.


Subject(s)
Clinical Deterioration , Neoplasms , Child , Humans , Infant , Prospective Studies , Medical Oncology , Intensive Care Units, Pediatric , Neoplasms/therapy , Retrospective Studies
10.
EJHaem ; 3(4): 1300-1304, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36467824

ABSTRACT

In Diamond-Blackfan anaemia (DBA), iron overload (IO) is common in transfusion-dependent patients, yet has also been reported in non-transfusion-dependent patients. We explored the incidence of IO in transfusion-dependent and non-transfusion-dependent DBA patients. We observed hepatic IO in 65% of patients analysed with MRI, including three patients that were only treated with transfusions in the past. Whereas overall ferritin levels and liver iron content correlated, ferritin levels did not reflect total body iron adequately. Our data suggest that transfusion burden in the past plays an important role in IO in DBA, and should be taken into account during follow up.

11.
Commun Biol ; 5(1): 1094, 2022 10 14.
Article in English | MEDLINE | ID: mdl-36241695

ABSTRACT

The myriad of available hepatocyte in vitro models provides researchers the possibility to select hepatocyte-like cells (HLCs) for specific research goals. However, direct comparison of hepatocyte models is currently challenging. We systematically searched the literature and compared different HLCs, but reported functions were limited to a small subset of hepatic functions. To enable a more comprehensive comparison, we developed an algorithm to compare transcriptomic data across studies that tested HLCs derived from hepatocytes, biliary cells, fibroblasts, and pluripotent stem cells, alongside primary human hepatocytes (PHHs). This revealed that no HLC covered the complete hepatic transcriptome, highlighting the importance of HLC selection. HLCs derived from hepatocytes had the highest transcriptional resemblance to PHHs regardless of the protocol, whereas the quality of fibroblasts and PSC derived HLCs varied depending on the protocol used. Finally, we developed and validated a web application (HLCompR) enabling comparison for specific pathways and addition of new HLCs. In conclusion, our comprehensive transcriptomic comparison of HLCs allows selection of HLCs for specific research questions and can guide improvements in culturing conditions.


Subject(s)
Induced Pluripotent Stem Cells , Pluripotent Stem Cells , Cell Differentiation/genetics , Hepatocytes/metabolism , Humans , Induced Pluripotent Stem Cells/metabolism , Transcriptome
12.
Mucosal Immunol ; 15(4): 605-619, 2022 04.
Article in English | MEDLINE | ID: mdl-35654837

ABSTRACT

Despite advances in immunosuppressive prophylaxis and overall supportive care, gastrointestinal (GI) graft-versus-host disease (GVHD) remains a major, lethal side effect after allogeneic hematopoietic stem cell transplantation (allo-HSCT). It has become increasingly clear that the intestinal epithelium, in addition to being a target of transplant-related toxicity and GVHD, plays an important role in the onset of GVHD. Over the last two decades, increased understanding of the epithelial constituents and their microenvironment has led to the development of novel prophylactic and therapeutic interventions, with the potential to protect the intestinal epithelium from GVHD-associated damage and promote its recovery following insult. In this review, we will discuss intestinal epithelial injury and the role of the intestinal epithelium in GVHD pathogenesis. In addition, we will highlight possible approaches to protect the GI tract from damage posttransplant and to stimulate epithelial regeneration, in order to promote intestinal recovery. Combined treatment modalities integrating immunomodulation, epithelial protection, and induction of regeneration may hold the key to unlocking mucosal recovery and optimizing therapy for acute intestinal GVHD.


Subject(s)
Graft vs Host Disease , Hematopoietic Stem Cell Transplantation , Intestinal Diseases , Acute Disease , Graft vs Host Disease/therapy , Hematopoietic Stem Cell Transplantation/adverse effects , Humans , Intestinal Diseases/etiology , Intestinal Diseases/therapy , Intestinal Mucosa/pathology , Intestines/pathology
13.
Pediatr Blood Cancer ; 69(5): e29636, 2022 05.
Article in English | MEDLINE | ID: mdl-35253341

ABSTRACT

Pediatric early warning systems (PEWS) arewidely used to identify clinically deteriorating patients. Hospitalized pediatric oncology patients are particularly prone to clinical deterioration. We assessed the PEWS performance to predict early clinical deterioration and the effect of PEWS implementation on patient outcomes in pediatric oncology patients. PubMED, EMBASE, and CINAHL databases were systematically searched from inception up to March 2020. Quality assessment was performed using the Prediction model study Risk-Of-Bias Assessment Tool (PROBAST) and the Cochrane Risk-of-Bias Tool. Nine studies were included. Due to heterogeneity of study designs, outcome measures, and diversity of PEWS, it was not possible to conduct a meta-analysis. Although the studies reported high sensitivity, specificity, and area under the receiver operating characteristics curve (AUROC) of PEWS detecting inpatient deterioration, overall risk of bias of the studies was high. This review highlights limited evidence on the predictive performance of PEWS for clinical deterioration and the effect of PEWS implementation.


Subject(s)
Clinical Deterioration , Neoplasms , Child , Humans , Inpatients , Medical Oncology , Neoplasms/therapy , ROC Curve , Retrospective Studies
14.
Genes (Basel) ; 13(3)2022 02 28.
Article in English | MEDLINE | ID: mdl-35328001

ABSTRACT

Diamond−Blackfan anemia (DBA) is one of the inherited bone marrow failure syndromes marked by erythroid hypoplasia. Underlying variants in ribosomal protein (RP) genes account for 80% of cases, thereby classifying DBA as a ribosomopathy. In addition to RP genes, extremely rare variants in non-RP genes, including GATA1, the master transcription factor in erythropoiesis, have been reported in recent years in patients with a DBA-like phenotype. Subsequently, a pivotal role for GATA-1 in DBA pathophysiology was established by studies showing the impaired translation of GATA1 mRNA downstream of the RP haploinsufficiency. Here, we report on a patient from the Dutch DBA registry, in which we found a novel hemizygous variant in GATA1 (c.220+2T>C), and an Iranian patient with a previously reported variant in the initiation codon of GATA1 (c.2T>C). Although clinical features were concordant with DBA, the bone marrow morphology in both patients was not typical for DBA, showing moderate erythropoietic activity with signs of dyserythropoiesis and dysmegakaryopoiesis. This motivated us to re-evaluate the clinical characteristics of previously reported cases, which resulted in the comprehensive characterization of 18 patients with an inherited GATA-1 defect in exon 2 that is presented in this case-series. In addition, we re-investigated the bone marrow aspirate of one of the previously published cases. Altogether, our observations suggest that DBA caused by GATA1 defects is characterized by distinct phenotypic characteristics, including dyserythropoiesis and dysmegakaryopoiesis, and therefore represents a distinct phenotype within the DBA disease spectrum, which might need specific clinical management.


Subject(s)
Anemia, Diamond-Blackfan , Anemia, Diamond-Blackfan/diagnosis , Anemia, Diamond-Blackfan/genetics , Anemia, Diamond-Blackfan/metabolism , Erythropoiesis/genetics , GATA1 Transcription Factor , Humans , Iran , Phenotype , Ribosomal Proteins/genetics
15.
Ned Tijdschr Geneeskd ; 1662022 01 12.
Article in Dutch | MEDLINE | ID: mdl-35138705

ABSTRACT

With the development of organoids as three-dimensional model organs it is now possible to mimic the growth of human organs in a culture dish. As these model organs can be generated from patients' (diseased) tissue and capture the (genetic) properties thereof, they are more representative disease models than cell lines and animal models. The use of organoids in pathophysiological research has already increased our understanding of many human diseases. Furthermore, organoids are used for patient-specific drug tests for cystic fibrosis, and this will soon be possible for other genetic diseases. Also, transplantation of (own genetically corrected) organoids could become a new treatment option. To fully employ the potential of organoids in medicine, cultures need to be standardized and further optimized for better organ/disease representation. With this, organoids hold the promise to quickly revolutionize personalized and regenerative medicine.


Subject(s)
Organoids , Regenerative Medicine , Animals , Humans , Organoids/metabolism , Regenerative Medicine/methods
16.
Liver Transpl ; 28(8): 1356-1366, 2022 08.
Article in English | MEDLINE | ID: mdl-35152544

ABSTRACT

For liver transplantations, human leukocyte antigen (HLA) matching is not routinely performed because observed effects have been inconsistent. Nevertheless, long-term liver transplantation outcomes remain suboptimal. The availability of a more precise HLA-matching algorithm, Predicted Indirectly Recognizable HLA Epitopes II (PIRCHE-II), now enables robust assessment of the association between HLA matching and liver transplantation outcomes. We performed a single-center retrospective cohort study of 736 liver transplantation patients. Associations between PIRCHE-II and HLAMatchmaker scores and mortality, graft loss, acute and chronic rejection, ischemic cholangiopathy, and disease recurrence were evaluated with Cox proportional hazards models. Associations between PIRCHE-II with 1-year, 2-year, and 5-year outcomes and severity of acute rejection were assessed with logistic and linear regression analyses, respectively. Subgroup analyses were performed for autoimmune and nonautoimmune indications, and patients aged 30 years and younger, and older than 30 years. PIRCHE-II and HLAMatchmaker scores were not associated with any of the outcomes. However, patients who received transplants for autoimmune disease showed more acute rejection and graft loss, and these risks negatively associated with age. Rhesus mismatch more than doubled the risk of disease recurrence. Moreover, PIRCHE-II was inversely associated with graft loss in the subgroup of patients aged 30 years and younger with autoimmune indications. The absence of associations between PIRCHE-II and HLAMatchmaker scores and the studied outcomes refutes the need for HLA matching for liver (stem cell) transplantations for nonautoimmune disease. For autoimmune disease, the activated immune system seems to increase risks of acute rejection and graft loss. Our results may suggest the benefits of transplantations with rhesus matched but PIRCHE-II mismatched donor livers.


Subject(s)
Autoimmune Diseases , Liver Transplantation , Algorithms , Graft Rejection/epidemiology , Graft Survival , HLA Antigens , Histocompatibility Testing , Humans , Liver Transplantation/adverse effects , Retrospective Studies
17.
J Inherit Metab Dis ; 45(2): 353-365, 2022 03.
Article in English | MEDLINE | ID: mdl-34671987

ABSTRACT

Inborn errors of metabolism (IEMs) comprise a diverse group of individually rare monogenic disorders that affect metabolic pathways. Mutations lead to enzymatic deficiency or dysfunction, which results in intermediate metabolite accumulation or deficit leading to disease phenotypes. Currently, treatment options for many IEMs are insufficient. Rarity of individual IEMs hampers therapy development and phenotypic and genetic heterogeneity suggest beneficial effects of personalized approaches. Recently, cultures of patient-own liver-derived intrahepatic cholangiocyte organoids (ICOs) have been established. Since most metabolic genes are expressed in the liver, patient-derived ICOs represent exciting possibilities for in vitro modeling and personalized drug testing for IEMs. However, the exact application range of ICOs remains unclear. To address this, we examined which metabolic pathways can be studied with ICOs and what the potential and limitations of patient-derived ICOs are to model metabolic functions. We present functional assays in patient ICOs with defects in branched-chain amino acid metabolism (methylmalonic acidemia), copper metabolism (Wilson disease), and transporter defects (cystic fibrosis). We discuss the broad range of functional assays that can be applied to ICOs, but also address the limitations of these patient-specific cell models. In doing so, we aim to guide the selection of the appropriate cell model for studies of a specific disease or metabolic process.


Subject(s)
Amino Acid Metabolism, Inborn Errors , Organoids , Amino Acid Metabolism, Inborn Errors/metabolism , Humans , Liver/metabolism , Membrane Transport Proteins/metabolism , Metabolic Networks and Pathways , Organoids/metabolism
19.
Genet Med ; 23(11): 2202-2207, 2021 11.
Article in English | MEDLINE | ID: mdl-34194004

ABSTRACT

PURPOSE: Recessive cytosolic aminoacyl-tRNA synthetase (ARS) deficiencies are severe multiorgan diseases, with limited treatment options. By loading transfer RNAs (tRNAs) with their cognate amino acids, ARS are essential for protein translation. However, it remains unknown why ARS deficiencies lead to specific symptoms, especially early life and during infections. We set out to increase pathophysiological insight and improve therapeutic possibilities. METHODS: In fibroblasts from patients with isoleucyl-RS (IARS), leucyl-RS (LARS), phenylalanyl-RS-beta-subunit (FARSB), and seryl-RS (SARS) deficiencies, we investigated aminoacylation activity, thermostability, and sensitivity to ARS-specific amino acid concentrations, and developed personalized treatments. RESULTS: Aminoacylation activity was reduced in all patients, and further diminished at 38.5/40 °C (PLARS and PFARSB), consistent with infectious deteriorations. With lower cognate amino acid concentrations, patient fibroblast growth was severely affected. To prevent local and/or temporal deficiencies, we treated patients with corresponding amino acids (follow-up: 1/2-2 2/3rd years), and intensified treatment during infections. All patients showed beneficial treatment effects, most strikingly in growth (without tube feeding), head circumference, development, coping with infections, and oxygen dependency. CONCLUSION: For these four ARS deficiencies, we observed a common disease mechanism of episodic insufficient aminoacylation to meet translational demands and illustrate the power of amino acid supplementation for the expanding ARS patient group. Moreover, we provide a strategy for personalized preclinical functional evaluation.


Subject(s)
Amino Acyl-tRNA Synthetases , Amino Acids , Amino Acyl-tRNA Synthetases/genetics , Aminoacylation , Humans , RNA, Transfer/metabolism
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