Myelodysplastic Syndromes in the Postgenomic Era and Future Perspectives for Precision Medicine.

Myelodysplastic syndromes (MDS) represent a heterogeneous group of clonal disorders caused by sequential accumulation of somatic driver mutations in hematopoietic stem and progenitor cells (HSPCs). MDS is characterized by ineffective hematopoiesis with cytopenia, dysplasia, inflammation, and a variable risk of transformation into secondary acute myeloid leukemia. The advent of next-generation sequencing has revolutionized our understanding of the genetic basis of the disease. Nevertheless, the biology of clonal evolution remains poorly understood, and the stochastic genetic drift with sequential accumulation of genetic hits in HSPCs is individual, highly dynamic and hardly predictable. These continuously moving genetic targets pose substantial challenges for the implementation of precision medicine, which aims to maximize efficacy with minimal toxicity of treatments. In the current postgenomic era, allogeneic hematopoietic stem cell transplantation remains the only curative option for younger and fit MDS patients. For all unfit patients, regeneration of HSPCs stays out of reach and all available therapies remain palliative, which will eventually lead to refractoriness and progression. In this review, we summarize the recent advances in our understanding of MDS pathophysiology and its impact on diagnosis, risk-assessment and disease monitoring. Moreover, we present ongoing clinical trials with targeting compounds and highlight future perspectives for precision medicine.

Utility of the Platelet Function Analyzer in Patients with Suspected Platelet Function Disorders: Diagnostic Accuracy Study.

Introduction The platelet function analyzer (PFA) is widely used as a screening tool for bleeding disorders in various settings. The diagnostic performance regarding platelet function disorders (PFDs), which are among the most common inherited bleeding disorders, is however still elusive. We aimed to assess the diagnostic value of PFA for PFD in clinical practice. Methods Comprehensive clinical and laboratory data of all consecutive patients referred to a specialized outpatient between January 2012 and March 2017 with a suspected bleeding disorder were prospectively recorded. The diagnostic work-up was performed according to a prespecified protocol following current guidelines and platelet function was tested using light transmission aggregometry as well as flow cytometry. Results Five hundred and fifty-five patients were included (median age 43.7 years; interquartile range [IQR] 29.3, 61.7; 66.9% female). Possible PFD was diagnosed in 64 patients (11.5%) and confirmed PFD in 54 patients (9.7%). In patients with confirmed PFD, median closure times were 107 seconds (ADP or adenosine diphosphate; IQR 89, 130) and 169 seconds (EPI; IQR 121, 211). In patients without bleeding disorders, PFA closure times were 96 seconds (ADP; IQR 83, 109) and 137 seconds (EPI; IQR 116, 158). The sensitivity was 19.5% in case of PFA ADP (95%CI 12.6, 30.0; specificity 86.4%; 95% CI 82.4, 89.8), and 44.3% in case of PFA EPI (95% CI 34.9, 53.9; specificity 75.6%; 95% CI 70.8, 79.9). Conclusion The diagnostic performance of PFA for PFD was moderate to poor. Our results do not support the utilization of PFA for screening of PFD in clinical practice.

The Inhibition of Complement System in Formal and Emerging Indications: Results from Parallel One-Stage Pairwise and Network Meta-Analyses of Clinical Trials and Real-Life Data Studies.

This manuscript presents quantitative findings on the actual effectiveness of terminal complement component 5 (C5) inhibitors and complement component 1 (C1) esterase inhibitors through their formal and common "off-label" (compassionate) indications. The results emanated from pairwise and network meta-analyses to present evidence until September 2019. Clinical trials (CT) and real-life non-randomized studies of the effects of interventions (NRSI) are consistent on the benefits of C5 inhibitors and of the absence of effects of C1 esterase inhibitors (n = 7484): Mathematically, eculizumab (surface under the cumulative ranking area (SUCRA) >0.6) and ravulizumab (SUCRA ≥ 0.7) were similar in terms of their protective effect on hemolysis in paroxysmal nocturnal hemoglobinuria (PNH), thrombotic microangiopathy (TMA) in atypical hemolytic uremic syndrome (aHUS), and acute kidney injury (AKI) in aHUS, in comparison to pre-/off-treatment state and/or placebo (SUCRA < 0.01), and eculizumab was efficacious on thrombotic events in PNH (odds ratio (OR)/95% confidence interval (95% CI) in CT and real-life NRSI, 0.07/0.03 to 0.19, 0.24/0.17 to 0.33) and chronic kidney disease (CKD) occurrence/progression in PNH (0.31/0.10 to 0.97, 0.66/0.44 to 0.98). In addition, meta-analysis on clinical trials shows that eculizumab mitigates a refractory generalized myasthenia gravis (rgMG) crisis (0.29/0.13 to 0.61) and prevents new acute antibody-mediated rejection (AMR) episodes in kidney transplant recipients (0.25/0.13 to 0.49). The update of findings from this meta-analysis will be useful to promote a better use of complement inhibitors, and to achieve personalization of treatments with this class of drugs.

The Impact of Iron Supplementation for Treating Anemia in Patients with Chronic Kidney Disease: Results from Pairwise and Network Meta-Analyses of Randomized Controlled Trials.

After relative erythropoietin deficiency, iron deficiency is the second most important contributing factor for anemia in chronic kidney disease (CKD) patients. Iron supplementation is a crucial part of the treatment of anemia in CKD patients, and intravenous (IV) iron supplementation is considered to be superior to per os (PO) iron supplementation. The differences between the available formulations are poorly characterized. This report presents results from pairwise and network meta-analyses carried out after a comprehensive search in sources of published and unpublished studies, according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) recommendations (International prospective register of systematic reviews PROSPERO reference ID: CRD42020148155). Meta-analytic calculations were performed for the outcome of non-response to iron supplementation (i.e., hemoglobin (Hgb) increase of <0.5-1.0 g/dL, or initiation/intensification of erythropoiesis-stimulating agent (ESA) therapy, or increase/change of iron supplement, or requirements of blood transfusion). A total of 34 randomized controlled trials (RCT) were identified, providing numerical data for analyses covering 93.7% (n = 10.097) of the total study population. At the network level, iron supplementation seems to have a more protective effect against the outcome of non-response before the start of dialysis than once dialysis is initiated, and some preparations seem to be more potent (e.g., ferumoxytol, ferric carboxymaltose), compared to the rest of iron supplements assessed (surface under the cumulative ranking area (SUCRA) > 0.8). This study provides parameters for adequately following-up patients requiring iron supplementation, by presenting the most performing preparations, and, indirectly, by making it possible to identify good responders among all patients treated with these medicines.

Diagnostic utility of the ISTH bleeding assessment tool in patients with suspected platelet function disorders.

Essentials The utility of bleeding assessment tools regarding platelet function disorders is still elusive. We studied consecutive patients in a prospective cohort study in a tertiary hospital. Substantially higher scorings were observed in patients with platelet function disorders. Bleeding assessment tools might provide a useful screening tool. BACKGROUND: Bleeding assessment tools (BATs) have been widely implemented in the evaluation of patients with suspected bleeding disorders. However, diagnostic BAT utility regarding platelet function disorders is still elusive. AIM: We aimed to assess the diagnostic value of the International Society on Thrombosis and Haemostasis BAT (ISTH-BAT) for platelet function disorders in clinical practice. METHODS: The clinical characteristics and laboratory data of all consecutive patients with a suspected bleeding disorder referred between January 2012 and March 2017 to an outpatient unit of a university hospital were prospectively collected. The diagnostic evaluation was performed according to current recommendations following a prespecified protocol and platelet function was tested using light transmission aggregometry as well as flow cytometry. RESULTS: Five hundred and fifty-five patients were assessed; 66.9% were female, median age was 43.7 years (interquartile range [IQR] 29.3, 61.7). Confirmed platelet function disorder was diagnosed in 54 patients (9.7%), possible platelet function disorder in 64 patients (11.5%), and other disorders in 170 patients (30.6%). Median scoring of the ISTH-BAT was 2 in patients without a bleeding disorder (IQR 1, 3), 4 in patients with a possible platelet function disorder (2, 7), and 7 in patients with confirmed platelet function disorder (5, 9). Area under the receiver operating characteristic curve (the area under the curve [AUC]) was 0.75 (95% CI 0.70, 0.80). CONCLUSIONS: Presence of a platelet function disorder was associated with substantially higher BAT scorings compared to patients without. Our data suggest that the ISTH-BAT provides a useful screening tool for patients with suspected platelet function disorders.

The number of FoxP3 regulatory T cells in the circulation may be a predictive biomarker for kidney transplant recipients: A multistage systematic review.

BACKGROUND: The kinetics of the FoxP3 regulatory T-cell (Treg) population in kidney transplant recipients (KTR) are related to the clinical effect of immunosuppression based on mammalian Target Of Rapamycin inhibitors (mTORi) with/without belatacept (predictive biomarker). METHODS: A multistage systematic review of published and unpublished literature is presented [registration IDs in the International Prospective Register of Systematic Reviews (PROSPERO): CRD42017057570, CRD42018085019, CRD42018084941, CRD42018085186]. A multidisciplinary supervision mechanism for contextualizing of search findings was required. The peripheral blood immune cell phenotypes encompassing all regulatory cells in KTRs were assessed in order to suggest new markers of acute rejection-associated acute allograft dysfunction (AR/AAD) events in KTRs treated with mTORi alone or combined to belatacept. Quantitative estimates and evaluation of the body of evidence are provided. RESULTS: An increase in Tregs and other regulatory cell types in the circulation in KTRs under mTORi with/without belatacept were observed. Patients with increased Tregs presented a low frequency of AR/AAD events compared to those in which the number of Tregs remained unchanged or even diminished [Odds Ratio (OR)/95% confidence interval (95% CI)/I2/number of studies (n): 0.31/0.10-0.93/0%/6]. Nevertheless, there are too few trials to consider Tregs in the circulation as a predictive biomarker. Inadequate reporting prevents appreciating clinical relevance in such studies. CONCLUSIONS: Despite advances, clinical qualification of potential predictive biomarkers continues to be difficult. Clinical evidence on Tregs in KTRs needs to be enlarged. Biomarkers should be able to evaluate the effect of medicines targeted to specific patient populations.

Data on a new biomarker for kidney transplant recipients: The number of FoxP3 regulatory T cells in the circulation.

This article presents unrevealed details of the systematic review process of the article "The number of FoxP3 regulatory T cells in the circulation may be a predictive biomarker for kidney transplant recipients: A multistage systematic review" (Herrera-Gómez et al., 2018). Eligibility criteria guiding searches and study selection, the risk of bias assessment, the assessment of medicine-test codependency (evaluation of the body of evidence), and meta-analytic calculations are provided. The data allows other researchers, particularly those involved in experiments on Translational Epidemiology applied to Pharmacology, to corroborate and extend our assessments.

Thromboelastometry and Thrombelastography Analysis under Normal Physiological Conditions - Systematic Review.

BACKGROUND: Studies investigating thromboelastometry or thrombelastography analyses in a physiological context are scattered and not easy to access. OBJECTIVE: To systematically retrieve and describe published reports studying healthy subjects and targeting at the correlation of ROTEM® and TEG® measurements with conventional parameters of hemostasis. METHODS: Systematic Review: Papers were searched in Medline, Scopus and the Science Citation Index database. Reference lists of included studies and of reviews were screened. To be included papers had to report ROTEM or TEG data on healthy subjects. Two reviewers screened papers for inclusion, read full texts of potentially relevant papers, and extracted data of included papers. RESULTS: Searches identified 1,721 records of which 1,713 were either excluded immediately or after reading the full text. The remaining 8 studies enrolled 632 subjects. The association of conventional parameters of hemostasis with ROTEM and with TEG was investigated in one and two studies, respectively. Overall correlation was limited and ranged from 0.0 to 0.40 (total thrombus generation vs. fibrinogen; clotting time INTEM vs. activated partial thromboplastin time). CONCLUSIONS: Studies assessing the relationship between thromboelastometry or thromboelastography analyses and conventional parameters of hemostasis in healthy subjects remains scarce, and correlations are limited. Further research is needed to understand the physiology of thromboelastometry and thromboelastography parameters.

Changes of Thyroid Hormones and Their Binding Proteins during Plasma Exchange for Polyneuropathy in a Patient with Substituted Hypothyroidism due to Hashimoto's Thyroiditis.

BACKGROUND: Pharmacodynamic studies and data concerning adaptation of thyroid substitution in patients with substituted hypothyroidism during plasma exchange (PE) is not available. CASE REPORT: We measured TSH, fT3 and fT4, total T4, thyroxin binding globulin (TBG), and albumin before and after 5 PE procedures in a 37-year-old women who underwent PE for a therapy-resistant polyneuropathy. Thyroxin was increased empirically by 8% resulting in a dose of 1.95 µg/kg per day. RESULTS: Despite larger reductions of total T4 and TBG over a series of 5 PEs (40-50% from baseline), only small reductions of 8% in fT3 and fT4 concentrations were documented with a concomittant increase in TSH level. Changes of fT4, fT3, and TSH remained within normal range. CONCLUSIONS: i) Despite a significant decrease in total thyroid hormone pool following PE, fT4, fT3, and TSH concentrations changed only slightly. ii) Based on this observation, a general increase in thyroid replacement therapy before PE cannot be recommended, but considered in case of a high normal TSH level.

PBMC transcriptomic responses to primary and secondary vaccination differ due to divergent lean growth and antibody titers in a pig model.

The genetic relationship between immune responsiveness and performance is not well understood, but a major topic of the evolution of resource allocation and of relevance in human medicine and livestock breeding, for instance. This study aims to show differences of transcript abundance changes during the time intervals before and after two tetanus toxoid (TT) vaccinations in domestic pigs differing in lean growth (LG) and anti-TT-antibody titers (AB) parameters of performance and immunocompetence. During response to the first vaccination all animals had a general decrease in transcript abundances related to various functional pathways as measured by comparative Affymetrix microarray hybridization and Ingenuity Pathway analyses. Low-AB phenotypes had predominantly decreased immune response transcripts. Combined phenotypes high-AB/high-LG had decreased transcripts related to growth factor signaling pathways. However, during the interval after the booster vaccination, high-LG and high-AB animals responded exclusively with increased immune transcripts, such as B-cell receptor signaling and cellular immune response pathways. In addition, high-LG and low-AB animals had predominantly increased transcripts of several cellular immune response pathways. Conversely, low-LG and high-AB animals had few elevated immune transcripts and decreased transcripts related to only two nonimmune-specific pathways. In response to booster vaccination high-LG phenotypes revealed enriched transcripts related to several different immune response pathways, regardless of AB phenotype. Different from the expected impact of AB titers, divergent AB phenotypes did not reflect considerable differences between immune transcripts. However, highly significant differences observed among divergent LG phenotypes suggest the compatibility of high performance and high vaccine responses.

Conjunctival MALT lymphoma: utility of FDG PET/CT for diagnosis, staging, and evaluation of treatment response.

A 67-year-old woman was referred for staging of a mucosa-associated lymphoid tumor lymphoma involving the left conjunctiva. CT scan had shown paravertebral and pelvic masses, and a breast nodule. FDG PET/CT demonstrated moderately increased uptake in the left ocular conjunctiva and confirmed the paravertebral and pelvic masses and the breast nodule. Moreover, abnormal FDG uptake was shown in 2 breast nodules, the flank, the gluteus maximus, and the gastric cardia. The patient received 6 cycles of rituximab-bendamustine chemotherapy with a complete clinical and metabolic response at the 6-month follow-up PET/CT and remained relapse-free without visual acuity problem after a 36-month follow-up.

[Thrombotic thrombocytopenic purpura--an often missed diagnosis]. / Le purpura thrombotique thrombocytopénique--un diagnostic méconnu.

Thrombotic thrombocytopenic purpura (TTP) is a disease characterized by mechanical anemia with fragmentation of red blood cells and thrombocytopenia by consumption. The physiopathology has been extensively studied and a severe deficiency of ADAMTS 13, proteolytic enzyme of von Willebrand factor (vWF), has been shown to be responsible for its manifestation. We stress the importance of visual blood smear examination when clinical and hematological features of TTP are present, as it seems to be under-diagnosed, especially in infants and young adults. Superpositions with diarrhea-associated hemolytic uremic syndrome (D+ HUS) and atypical HUS (aHUS) are controversely discussed. Henceforth this article proposes a non-exhaustive review of current diagnostic, therapeutic and prognostic features of these diseases.

PBMC transcription profiles of pigs with divergent humoral immune responses and lean growth performance.

BACKGROUND: The identification of key genes and regulatory networks in the transcriptomic responses of blood cells to antigen stimulation could facilitate the understanding of host defence and disease resistance. Moreover, genetic relationships between immunocompetence and the expression of other phenotypes, such as those of metabolic interest, are debated but incompletely understood in farm animals. Both positive and negative associations between immune responsiveness and performance traits such as weight gain or lean growth have been reported. We designed an in vivo microarray study of transcriptional changes in porcine peripheral blood mononuclear cells (PBMCs) during the immune response to tetanus toxoid (TT) as a model antigen for combined cellular (Th1) and humoral (Th2) responses. The aim of the study was to investigate the responsiveness of PBMCs against the background of divergent lean growth (LG) performance and anti-TT antibody (AB) titers and to compare lean growth and humoral immune performance phenotypes. RESULTS: In general, high LG phenotypes had increased cellular immune response transcripts, while low AB phenotypes had increased transcripts for canonical pathways that represented processes of intracellular and second messenger signaling and immune responses. Comparison of lean growth phenotypes in the context of high AB titers revealed higher cellular immune response transcripts in high LG phenotypes. Similar comparisons in the context of low AB titers failed to identify any corresponding pathways. When high and low AB titer phenotypes were differentially compared, low AB phenotypes had higher cellular immune response transcripts on a low LG background and higher cell signaling, growth, and proliferation transcripts on a high LG background. CONCLUSIONS: Divergent phenotypes of both lean growth performance and humoral immune response are affected by significant and functional transcript abundance changes throughout the immune response. The selected high-performance phenotypes demonstrated both high AB titers and increased transcript abundance of cellular immune response genes, which were possibly offset by lower expression of other cellular functions. Further, indications of compensatory effects were observed between cellular and humoral immune responses that became visible only in low-performance phenotypes.

Transcriptomic response of porcine PBMCs to vaccination with tetanus toxoid as a model antigen.

The aim of the present study was to characterize in vivo genome-wide transcriptional responses to immune stimulation in order to get insight into the resulting changes of allocation of resources. Vaccination with tetanus toxoid was used as a model for a mixed Th1 and Th2 immune response in pig. Expression profiles of PBMCs (peripheral blood mononuclear cells) before and at 12 time points over a period of four weeks after initial and booster vaccination at day 14 were studied by use of Affymetrix GeneChip microarrays and Ingenuity Pathway Analysis (IPA). The transcriptome data in total comprised more than 5000 genes with different transcript abundances (DE-genes). Within the single time stages the numbers of DE-genes were between several hundred and more than 1000. Ingenuity Pathway Analysis mainly revealed canonical pathways of cellular immune response and cytokine signaling as well as a broad range of processes in cellular and organismal growth, proliferation and development, cell signaling, biosynthesis and metabolism. Significant changes in the expression profiles of PBMCs already occurred very early after immune stimulation. At two hours after the first vaccination 679 DE-genes corresponding to 110 canonical pathways of cytokine signaling, cellular immune response and other multiple cellular functions were found. Immune competence and global disease resistance are heritable but difficult to measure and to address by breeding. Besides QTL mapping of immune traits gene expression profiling facilitates the detection of functional gene networks and thus functional candidate genes.

Electrochemical product detection of an asymmetric convective polymerase chain reaction.

For the first time, we describe the application of heated microwires for an asymmetric convective polymerase chain reaction (PCR) in a modified PCR tube in a small volume. The partly single-stranded product was labeled with the electrochemically active compound osmium tetroxide bipyridine using a partially complementary protective strand with five mismatches compared to the single-stranded product. The labeled product could be successfully detected at a gold electrode modified with a complementary single-stranded capture probe immobilized via a thiol-linker. Our simple thermo-convective PCR yielded electrochemically detectable products after only 5-10 min. A significant discrimination between complementary and non-complementary target was possible using different immobilized capture probes. The total product yield was approx. half the amount of the classical thermocycler PCR. Numerical simulations describing the thermally driven convective PCR explain the received data. Discrimination between complementary capture probes and non-complementary capture probes was performed using square-wave voltammetry. The coupling of asymmetric thermo-convective PCR with electrochemical detection is very promising for future compact DNA sensor devices.