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Despite the various treatments proposed with barrier membranes, one of the main challenges for guided bone regeneration (GBR) is maintaining space for large defects and ensuring an adequate blood supply. The presented feasibility case series aims to introduce an original titanium frame (TF) design, customized for each defect, as a modification of well-known principles and materials for GBR to achieve an enhanced and more predictable horizontal and vertical bone augmentation. Three patients with significant horizontal defects were treated with pre-trimmed TFs to create needed space, and then a 50/50 mixture of autograft and bovine xenograft was placed and covered with a collagen membrane. After 8 months of healing, the sites were reopened, and the titanium screws were removed with the frame. An average of 8.0 ± 1.0 mm of horizontal and 3.0 ± 0.0 mm of vertical bone gain were achieved at the time of reentry and implant placement surgery. Bone core biopsy sample was obtained during the implant placement. Histomorphometric analysis revealed that 42.8% of the sample was new vital bone, 18.8% was residual bone graft particles, and 38.4% was bone marrow-like structures. After 3 to 4 months from implant placement, the implants were restored with provisional crowns and then finalized with zirconia screw-retained crowns. This case series suggests that GBR utilizing TFs with or without collagen membranes can be considered a suitable approach for horizontal and vertical bone augmentation. However, based on only three reported cases, the results should be carefully interpreted. [ABSTRACT FROM AUTHOR]

Post-allogeneic hematopoietic cell transplant (HCT) immunosuppression regimens are given as graft-versus-host disease (GVHD) prophylaxis. Most GVHD prophylaxis regimens are based on calcineurin inhibitors (CNIs). Unfortunately, CNIs are associated with significant associated morbidity, frequently cannot be tolerated, and often need to be discontinued. There is no consensus as to which alternative immunosuppression should be used in cases where CNIs have to be permanently discontinued. Cytotoxic T-lymphocyte-associated protein 4-immunoglobulin (CTLA4-Ig) blocking agents are well tolerated and have been used extensively in patients with autoimmune disease and as post-transplant immunosuppression. There are two CTLA4-Ig agents: belatacept and abatacept. Belatacept is routinely used in adult kidney transplantation to prevent rejection and abatacept has been approved by the Food and Drug Administration (FDA) for GVHD prophylaxis in patients undergoing a matched or one allele-mismatched unrelated allogenic HCT. Herein, we describe a case in which abatacept was given off-label to replace tacrolimus GVHD prophylaxis in a patient with neurotoxicity undergoing haploidentical HCT. This case suggests that CTLA4-Ig blockade may be a good alternative to a CNI in cases where the CNI needs to be discontinued and warrants further investigation.

Brown and brown-like adipose tissues have attracted significant attention for their role in metabolism and therapeutic potential in diabetes and obesity. Despite compelling evidence of an interplay between adipocytes and lymphocytes, the involvement of these tissues in immune responses remains largely unexplored. This study explicates a newfound connection between neuroinflammation and brown- and bone marrow adipose tissue. Leveraging the use of [18F]F-AraG, a mitochondrial metabolic tracer capable of tracking activated lymphocytes and adipocytes simultaneously, we demonstrate, in models of glioblastoma and multiple sclerosis, the correlation between intracerebral immune infiltration and changes in brown- and bone marrow adipose tissue. Significantly, we show initial evidence that a neuroinflammation-adipose tissue link may also exist in humans. This study proposes the concept of an intricate immuno-neuro-adipose circuit, and highlights brown- and bone marrow adipose tissue as an intermediary in the communication between the immune and nervous systems. Understanding the interconnectedness within this circuitry may lead to advancements in the treatment and management of various conditions, including cancer, neurodegenerative diseases and metabolic disorders.

Background: The optimal choice for graft‐versus‐host disease (GVHD) prophylaxis in haploidentical stem cell transplantation (haplo‐SCT) remains debatable. Posttransplant cyclophosphamide (PTCy) and anti‐thymocyte globulin (ATG) are two common strategies, but little is known about their combination. Methods: Using the European Society for Blood and Marrow Transplantation (EBMT) registry, the authors identified 3649 adult patients with acute myeloid leukemia (AML) who underwent haplo‐SCT in complete remission between 2007 and 2021 at 260 EBMT‐participating centers who received either PTCy (n = 2999), ATG (n = 358), or combination prophylaxis (n = 292). Cord blood transplants, combined bone marrow and peripheral grafts, and transplants with ex vivo graft manipulation were excluded. Median follow‐up was 31.8 months. Results: On multivariate analysis, adjusting for patient age and performance status, disease status at transplant, cytogenetic risk, conditioning intensity, stem cell source, female‐to‐male graft, and donor and patient CMV status, we present the following. Compared to PTCy, ATG had a higher risk of nonrelapse mortality (hazard ratio [HR], 1.6; p =.003), worse leukemia‐free survival (HR, 1.4; p =.002), overall survival (HR, 1.49; p =.0009), and GVHD‐free and relapse‐free survival (HR, 1.29; p =.012). The combination of PTCy and ATG, however, led to significantly reduced rates of grade 2–4 (HR, 0.51; p =.0003) and grade 3–4 (HR, 0.5; p =.018) acute GVHD and did not affect any transplant outcomes compared to PTCy without ATG. Conclusion: The authors conclude that ATG alone is a less effective prophylaxis strategy compared to PTCy, however, the combination of PTCy and ATG is superior to either monotherapy. They propose that this combination could be considered a potential new standard of care for GVHD prophylaxis in haplo‐SCT for AML. This study analyzed 3649 adult acute myeloid leukemia (AML) patients undergoing haploidentical stem cell transplantation (haplo‐SCT) with either posttransplant cyclophosphamide (PTCy), anti‐thymocyte globulin (ATG), or their combination, and showed that ATG alone had worse outcomes compared to PTCy, but combining PTCy and ATG significantly reduced acute graft‐vs‐host disease (GVHD) rates without affecting transplant outcomes. This suggests the PTCy and ATG combination could be a superior GVHD prophylaxis strategy in haplo‐SCT for AML. [ABSTRACT FROM AUTHOR]

To assess the efficacy of a novel 3D biomimetic hydrogel scaffold with immunomodulatory properties in promoting fracture healing. Immunomodulatory scaffolds were used in cell experiments, osteotomy mice treatment, and single-cell transcriptomic sequencing. In vitro, fluorescence tracing examined macrophage mitochondrial transfer and osteogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs). Scaffold efficacy was assessed through alkaline phosphatase (ALP), Alizarin Red S (ARS) staining, and in vivo experiments. The scaffold demonstrated excellent biocompatibility and antioxidant-immune regulation. Single-cell sequencing revealed a shift in macrophage distribution towards the M2 phenotype. In vitro experiments showed that macrophage mitochondria promoted BMSCs' osteogenic differentiation. In vivo experiments confirmed accelerated fracture healing. The GAD/Ag-pIO scaffold enhances osteogenic differentiation and fracture healing through immunomodulation and promotion of macrophage mitochondrial transfer. [ABSTRACT FROM AUTHOR]

Introduction Methods Results Conclusion Hematopoietic stem cell transplantation (HCST) is a widely used therapy in the management of hematological malignancies, leading to cytopenias that require transient transfusions. Platelet recovery (PR) following HSCT is assessed by monitoring platelet count (PC). Immature platelet fraction (IPF) is a research parameter offered by Sysmex® on XN series analyzers, enabling rapid diagnostic orientation in the event of thrombocytopenia. It has also been described as a predictive factor for PR after chemotherapy or HSCT, and thresholds have been proposed.The objective of this study was to assess the predictive capability of IPF for PR in a prospective cohort of patients undergoing HSCT and to evaluate its utility in guiding platelet transfusion decision.An optimized A‐IPF (absolute number of IPF) threshold of 2.5 × 109/L was predictive of a PC greater than 50 × 109/L at day 30 with a sensitivity of 78.9%, specificity of 78.6%, positive predictive value (PPV) of 83.3% and negative predictive value (NPV) of 73.3%. We were able to distinguish patients recovering PC before day 15 with an earlier %IPF peak, greater IPF recovery kinetics and faster neutrophil recovery.A‐IPF shows promise as a predictor of PR following HSCT. A multicenter study could help confirm both A‐IPF and %IPF (IPF) clinical utility before it is made available to clinicians. [ABSTRACT FROM AUTHOR]

Nephropathic cystinosis (NC) is a rare autosomal recessive lysosomal storage disease characterized by defective lysosomal efflux of cystine due to variations in the CTNS gene encoding the lysosomal cystine transporter, cystinosin. This leads to pathological crystal accumulation in almost all tissues and organs in the body, affecting their functions. NC primarily affects the kidneys followed by a cascade of extrarenal organ involvement later in life. There are few reports of hematological complications as anemia or cytopenias; nevertheless, most of the reported data have been derived from case reports or small case series. Anemia/cytopenias in NC can be multifactorial in origin. Early identification and timely management of these alterations are critical to better growth, improved outcome, and quality of life of NC patients. Early diagnosis of NC, early initiation of both supportive and definitive cystine-depleting treatment, and adherence to therapy remain the mainstay for disease control and prevention of progression of some extrarenal complications. We hereby review hematological findings in NC, discuss the underlying contributing factors, suggest work-up, and highlight treatment options for hematological complications in NC patients. Given the multisystem nature of NC, we recommend integrated NC care approach with involvement of hematologist into its multidisciplinary team. [ABSTRACT FROM AUTHOR]

Background: The immunomodulatory oligodeoxynucleotide (ODN) IMT504 might harbor antifibrotic properties within the liver. Methods: Fibrosis models were induced in mice through thioacetamide (TAA) administration and bile-duct ligation. Cre-loxP mice were utilized to identify GLAST + Wnt1 + bone marrow stromal progenitors (BMSPs) and to examine their contribution with cells in the liver. In vivo and in vitro assays; flow-cytometry, immunohistochemistry, and qPCR were conducted. Results: IMT504 demonstrated significant inhibition of liver fibrogenesis progression and reversal of established fibrosis. Early responses to IMT504 involved the suppression of profibrogenic and proinflammatory markers, coupled with an augmentation of hepatocyte proliferation. Additionally, this ODN stimulated the proliferation and mobilization of GLAST + Wnt1 + BMSPs, likely amplifying their contribution with endothelial- and hepatocytes-like cells. Moreover, IMT504 significantly modulated the expression levels of Wnt ligands and signaling pathway/target genes specifically within GLAST + Wnt1 + BMSPs, with minimal impact on other BMSPs. Intriguingly, both IMT504 and conditioned media from IMT504-pre-treated GLAST + Wnt1 + BMSPs shifted the phenotype of fibrotic macrophages, hepatic stellate cells, and hepatocytes, consistent with the potent antifibrotic effects observed. Conclusion: In summary, our findings identify IMT504 as a promising candidate molecule with potent antifibrotic properties, operating through both direct and indirect mechanisms, including the activation of GLAST + Wnt1 + BMSPs. [ABSTRACT FROM AUTHOR]

Recent advances in imaging suggested that spatial organization of hematopoietic cells in their bone marrow microenvironment (niche) regulates cell expansion, governing progression, and leukemic transformation of hematological clonal disorders. However, our ability to interrogate the niche in pre-malignant conditions has been limited, as standard murine models of these diseases rely largely on transplantation of the mutant clones into conditioned mice where the marrow microenvironment is compromised. Here, we leveraged live-animal microscopy and ultralow dose whole body or focal irradiation to capture single cells and early expansion of benign/pre-malignant clones in the functionally preserved microenvironment. 0.5 Gy whole body irradiation (WBI) allowed steady engraftment of cells beyond 30 weeks compared to non-conditioned controls. In-vivo tracking and functional analyses of the microenvironment showed no change in vessel integrity, cell viability, and HSC-supportive functions of the stromal cells, suggesting minimal inflammation after the radiation insult. The approach enabled in vivo imaging of Tet2+/− and its healthy counterpart, showing preferential localization within a shared microenvironment while forming discrete micro-niches. Notably, stationary association with the niche only occurred in a subset of cells and would not be identified without live imaging. This strategy may be broadly applied to study clonal disorders in a spatial context. [ABSTRACT FROM AUTHOR]

An approximately 26‐year‐old, suspected female, red‐tailed hawk (Buteo jamaicensis) was presented with a history of chronic ocular changes of the left eye likely secondary to blunt trauma resulting in blindness and phthisis bulbi. Ophthalmic evaluation of OS revealed a large intraocular mass, 3+ aqueous flare indicating anterior uveitis, and severely decreased intraocular pressure measuring 5 mmHg. Ocular ultrasound revealed an abnormal, spherical shaped and hyperechoic lens, as well as hyperechoic material or a mass lesion in the posterior segment. An enucleation procedure was performed, and histopathology of the eye revealed no signs of neoplasia but instead intraocular osseous metaplasia with bone marrow and adipose tissue replacing the lens. Similar mass lesions were found in the retina and choroid. Multiple fractures in the scleral ossicle and cartilage correlated the intraocular lesions with a blunt traumatic event. A bioresorbable disk of porcine small intestine submucosa (BioSIS Vetrix®) was incorporated to relieve tension during closure. The graft sloughed during healing process, revealing a healed wound underneath. The BioSIS was not incorporated into the wound as designed but may have facilitated healing. This is the first report of intraocular osseous metaplasia in a raptor and the use of BioSIS Vetrix® with enucleation in an avian species. [ABSTRACT FROM AUTHOR]

Summary MYSM1 deficiency causes inherited bone marrow failure syndrome (IBMFS). We have previously identified an IBMFS patient with a homozygous pathogenic variant in MYSM1 who recovered from cytopenia due to spontaneous correction of one MYSM1 variant in the haematopoietic compartment, an event called somatic genetic rescue (SGR). The study of the genetic and biological aspects of the patient's haematopoietic/lymphopoietic system over a decade after SGR shows that one genetically corrected haematopoietic stem cell (HSC) can restore a healthy and stable haematopoietic system. This supports in vivo gene correction of HSCs as a promising treatment for IBMFS, including MYSM1 deficiency. [ABSTRACT FROM AUTHOR]

Introduction Military members and first responders may, at moment's notice, be asked to assist in incidents that may result in radiation exposure such as Operation Tomadachi in which the U.S. Navy provided significant relief for the Fukushima Daiichi Nuclear Reactor accident in Japan after an earthquake and tsunami in 2011. We are also currently facing potential threats from nuclear power plants in the Ukraine should a power disruption to a nuclear plant interfere with cooling or other safety measures. Exposure to high doses of radiation results in acute radiation syndrome (ARS) characterized by symptoms arising from hematopoietic, gastrointestinal, and neurovascular injuries. Although there are mitigators FDA approved to treat ARS, there are currently no FDA-approved prophylactic medical interventions to help protect persons who may need to respond to radiation emergencies. There is strong evidence that manganese (Mn) has radiation protective efficacy as a promising prophylactic countermeasure. Materials and Methods All animal procedures were approved by the Institutional Animal Care and Use Committee. Male and female B6D2F1J mice, 10 to 11 weeks old, were used for neurotoxicity studies and temporal effects of Mn. Four groups were evaluated: (1) vehicle injection, (2) dose of 4.5 mg/kg for 3 days, (3) dose of 13.5 mg/kg, and (4) sham. Irradiated mice were exposed to 9.5 Gy whole body Co60 γ-radiation. MRI was performed with a high dose of manganese chloride (MnCl2) (150 mg/kg) to assess the distribution of the MnCl2. Results The mice have promising survival curves (highest survival—13.5 mg/kg dose over 3 days of MnCl2 at 80% [87% female, 73% male] P  = 0.0004). The complete blood count (CBC) results demonstrated a typical hematopoietic response in all of the irradiated groups, followed by mildly accelerated recovery by day 28 in the treated groups. No difference between groups was measured by Rota Rod, DigiGait, and Y-maze. Histologic evaluation of the bone marrow sections in the group given 13.5 mg/kg dose over 3 days had the best return to cellularity at 80%. MRI showed a systemic distribution of MnCl2. Discussion The preliminary data suggest that a dose of 13.5 mg/kg of MnCl2 given over 3 days prior to exposure of radiation may have a protective benefit while not exhibiting the neurobehavioral problems. A countermeasure that can prophylactically protect emergency personnel entering an area contaminated with high levels of radiation is needed, especially in light that nuclear accidents are a continued global threat. There is a need for a protective agent with easy long-term storage, easy to transport, easy to administer, and low cost. Histologic evaluation supports the promising effect of MnCl2 in protecting tissue, especially the bone marrow using the dose given over 3 days (4.5 mg/kg per day) of MnCl2. Conclusions Initial experiments show that MnCl2 is a promising safe and effective prophylactic countermeasure against ARS. MRI data support the systemic distribution of MnCl2 which is needed in order to protect multiple tissues in the body. The pathology data in bone marrow and the brain support faster recovery from radiation exposure in the treated animals and decreased organ damage. [ABSTRACT FROM AUTHOR]

Extracellular vesicles (EVs) are heterogeneous, phospholipid membrane enclosed particles that are secreted by healthy and cancerous cells. EVs are present in diverse biological fluids and have been associated with the severity of diseases, which indicates their potential as biomarkers for diagnosis, prognosis and as therapeutic targets. This study investigated the phenotypic characteristics of EVs derived from peripheral blood (PB) and bone marrow (BM) in pediatric patients with B-cell acute lymphoblastic leukemia (B-ALL) during different treatment stages. PB and BM plasma were collected from 20 B-ALL patients at three time points during induction therapy, referred to as: diagnosis baseline (D0), day 15 of induction therapy (D15) and the end of the induction therapy (D35). In addition, PB samples were collected from 10 healthy children at a single time point. The EVs were measured using CytoFLEX S flow cytometer. Calibration beads were employed to ensure accurate size analysis. The following, fluorescent-labeled specific cellular markers were used to label the EVs: Annexin V (phosphatidylserine), CD235a (erythrocyte), CD41a (platelet), CD51 (endothelial cell), CD45 (leukocyte), CD66b (neutrophil), CD14 (monocyte), CD3 (T lymphocyte), CD19, CD34 and CD10 (B lymphoblast/leukemic blast). Our results demonstrate that B-ALL patients had a marked production of EV-CD51/61+, EV-CD10+, EV-CD19+ and EV-CD10+CD19+ (double-positive) with a decrease in EV-CD41a+ on D0. However, the kinetics and signature of production during induction therapy revealed a clear decline in EV-CD10+ and EV-CD19+, with an increase of EV-CD41a+ on D35. Furthermore, B-ALL patients showed a complex biological network, exhibiting distinct profiles on D0 and D35. Interestingly, fold change and ROC curve analysis demonstrated that EV-CD10+ CD19+ were associated with B-ALL patients, exhibited excellent clinical performance and standing out as a potential diagnostic biomarker. In conclusion, our data indicate that EVs represent a promising field of investigation in B-ALL, offering the possibility of identifying potential biomarkers and therapeutic targets. [ABSTRACT FROM AUTHOR]

Introduction: Pediatric patients with unexplained bone marrow failure (BMF) are often categorized as aplastic anemia (AA). Based on the accepted hypothesis of an auto-immune mechanism underlying AA, immune suppressive therapy (IST) might be effective. However, due to the lack of diagnostic tools to identify immune AA and prognostic markers to predict IST response together with the unequaled curative potential of hematopoietic stem cell transplantation (HSCT), most pediatric severe AA patients are momentarily treated by HSCT if available. Although several studies indicate oligoclonal T-cells with cytotoxic activities towards the hematopoietic stem cells, increasing evidence points towards defective inhibitory mechanisms failing to inhibit auto-reactive T-cells. Methods: We aimed to investigate the role of NK- and B-cells in seven pediatric AA patients through a comprehensive analysis of paired bone marrow and peripheral blood samples with spectral flow cytometry in comparison to healthy age-matched bone marrow donors. Results: We observed a reduced absolute number of NK-cells in peripheral blood of AA patients with a skewed distribution towards CD56bright NK-cells in a subgroup of patients. The enriched CD56bright NK-cells had a lower expression of CD45RA and TIGIT and a higher expression of CD16, compared to healthy donors. Functional analysis revealed no differences in degranulation. However, IFN-g production and perforin expression of NK-cells were reduced in the CD56bright-enriched patient group. The diminished NK-cell function in this subgroup might underly the auto-immunity. Importantly, NK-function of AA patients with reduced CD56bright NK-cells was comparable to healthy donors. Also, B-cell counts were lower in AA patients. Subset analysis revealed a trend towards reduction of transitional B-cells in both absolute and relative numbers compared to healthy controls. As these cells were previously hypothesized as regulatory cells in AA, decreased numbers might be involved in defective inhibition of auto-reactive T-cells. Interestingly, even in patients with normal distribution of precursor B-cells, the transitional compartment was reduced, indicating partial differentiation failure from immature to transitional B-cells or a selective loss. Discussion: Our findings provide a base for future studies to unravel the role of transitional B-cells and CD56bright NK-cells in larger cohorts of pediatric AA patients as diagnostic markers for immune AA and targets for therapeutic interventions. [ABSTRACT FROM AUTHOR]

Introduction: CD80, a co-stimulatory molecule required for optimal T cell activation, is expressed on antigen-presenting cells, including monocytes and dendritic cells, in dogs and humans. We hypothesized that CD80 would be expressed on tumor cells in dogs from acute myeloid leukemia (AML) but not dogs with lymphoid neoplasms. Methods and results: We first evaluated the cellular staining pattern of a hamster anti-murine CD80 antibody (clone 16-10A1, ThermoFisher Scientific Cat# 17– 0801-82, RRID: AB_469417) in blood and bone marrow aspirates from healthy dogs. Using flow cytometric analysis and examination of modified Wright’sstained cytologic smears of unsorted and flow cytometric or immunomagnetic bead-sorted leukocytes, we show that the antibody binds to mature and immature neutrophils and monocytes, but not lymphocytes or eosinophils, in blood and bone marrow. We then added the antibody to routine flow cytometric panels for immunophenotyping hematopoietic neoplasms in dogs. We found that the antibody labeled tumor cells in 72% of 39 dogs with AML and 36% of 11 dogs with acute leukemia expressing lymphoid and myeloid markers (“mixed lineage”) but none of the dogs with B (n  =  37) or T (n  =  35) lymphoid neoplasms. A higher proportion of tumor cells in dogs with AML were labeled with the anti-CD80 antibody vs antibodies against other myeloid-associated antigens, including CD4 (36%, p  =  0.003), CD11b (44%), CD11c (46%), CD14 (38%, p  =  0.006) and CD18 (59%, clone YFC118). In contrast, antibodies against CD11b and CD11c bound to tumor cells in 8–32% of the lymphoid neoplasms. Discussion: We show that CD80, as detected by antibody clone 16-10A1, is a sensitive and specific marker for AML and would be useful to include in flow cytometric immunophenotyping panels in dogs. [ABSTRACT FROM AUTHOR]

Background Allogeneic hematopoietic stem cell transplant for myeloid neoplasms with increased fibrosis is uncommon; morphologic features posttransplant can be concerning for persistent disease. Methods In this retrospective study, we identified 22 patients transplanted for myeloproliferative neoplasms or chronic myelomonocytic leukemia with fibrosis at our institution, and reviewed slides from pretransplant and posttransplant bone marrow biopsies. Clinical features and results of molecular, chimerism, and cytogenetic studies were retrieved from the medical record. Results Pretransplant bone marrow biopsies commonly exhibited hypercellularity, atypical megakaryocytes, and reticulin fibrosis. At day 100, 36% of biopsies had reticulin grade >MF1 and 33% of those tested had positive molecular studies, with no significant associations between day 100 marrow characteristics and molecular profile or peripheral count recovery times. In the 1 year posttransplant biopsies (n = 12), 7 of 9 had negative molecular studies; of these, none had reticulin grade >MF1, 1 had trichrome 1+, 2 had atypical megakaryocytes, and 1 was hypercellular. Conclusions Supporting recent literature, our study indicates that persistent day 100 reticulin fibrosis/collagen deposition does not show an association with day 100 molecular status. Our study additionally provides data for 12 patients with 1 year posttransplant marrow biopsies, with the majority of those lacking either increased fibrosis or molecular evidence of persistent disease. [ABSTRACT FROM AUTHOR]

Objectives Measurable residual disease flow cytometry (MRD-FC) and molecular studies are the most sensitive methods for detecting residual malignant populations after therapy for TP53 -mutated acute myeloid leukemia and myelodysplastic neoplasms (TP53+ AML/MDS). However, their sensitivity is limited in suboptimal aspirates or when the immunophenotype of the neoplastic blasts overlaps with erythroids or normal maturing myeloid cells. In this study, we set out to determine if p53 immunohistochemistry (IHC) correlates with MRD-FC and next-generation sequencing (NGS) in the posttherapy setting and to determine the utility of p53 IHC to detect residual disease in the setting of negative or equivocal MRD-FC. Methods We retrospectively identified 28 pre- and posttherapy bone marrow biopsy specimens from 9 patients with TP53+ AML/MDS and a p53 overexpressor phenotype by IHC (strong 3+ staining at initial diagnosis). Next-generation sequencing and/or MRD-FC results were collected for each specimen. Results Using a threshold of more than ten 2-3+ cells in any one 400× field, p53 IHC detected residual disease with a sensitivity of 94% and a specificity of 89%. The threshold used in this study showed a high degree of concordance among 6 blinded pathologists (Fleiss κ = 0.97). Conclusions Our study suggests that p53 IHC can be used as a rapid tool (within 24 hours) to aid in the detection of residual disease that may complement MRD-FC or NGS in cases in which the flow cytometry immunophenotype is equivocal and/or the bone marrow aspirate is suboptimal. [ABSTRACT FROM AUTHOR]

Objectives Myeloproliferative neoplasm, unclassifiable (MPN-U, revised to MPN, not otherwise specified in the fifth edition of the World Health Organization classification) is a heterogeneous category of primary marrow disorders with clinical, morphologic, and/or molecular features that preclude classification as a more specific MPN subtype due to stage at diagnosis, overlapping features between MPN subtypes, or the presence of coexisting disorders. Compared with other MPN subtypes, the contribution of the mutational landscape in MPN-U in conjunction with other clinical and morphologic biomarkers to prognosis has been less well investigated. Methods We performed a multicenter, retrospective study of MPN-U (94 cases) to better define the clinicopathologic features, genetic landscape, and clinical outcomes, including subgroups of early-stage, advanced-stage, and coexisting disorders. The Dynamic International Prognostic Scoring System (DIPSS) plus scoring system was applied to assess its relevance to MPN-U prognosis. Results Multivariate analysis demonstrated bone marrow blast count and DIPSS plus score as statistically significant in predicting overall survival. Univariate analysis identified additional potential poor prognostic markers, including abnormal karyotype and absence of JAK2 mutation. Secondary mutations were frequent in the subset analyzed by next-generation sequencing (26/37 cases, 70.3%) with a borderline association between high molecular risk mutations and overall survival. Conclusions This study, as one of the largest of MPN-U studies incorporating both clinicopathologic and molecular data, moves toward identification of biomarkers that better predict prognosis in this heterogeneous category. [ABSTRACT FROM AUTHOR]

Background: In patients who require venom immunotherapy (VIT), there is a need to identify underlying mast cell (MC) disorders since these may affect the risk and severity of future sting reactions and the long‐term effectiveness of VIT. Methods: 1319 individuals with Hymenoptera venom allergy (HVA) who needed VIT from referral centers in Slovenia, Austria, Croatia, and Poland underwent examination for KIT p.D816V in peripheral blood leukocytes (PBL) using a highly sensitive PCR test and tryptase genotyping by digital droplet PCR. We also included 183 control individuals with large local reactions (LLRs) to Hymenoptera stings and with asymptomatic sensitization to Hymenoptera venoms. Results: 285 of 1319 individuals recommended for VIT (21.6%) were positive for KIT p.D816V in PBL, preferably those who present with severe reaction (33.9% [n = 207 of 610] with Ring‐Messmer grade 3–4 vs. 11% [n = 78 of 709] with Grade 1–2; p <.0001), whereas only 1.3% (n = 2 of 152) of controls with LLR and none with asymptomatic sensitization (n = 31) had KIT p.D816V. KIT p.D816V allelic burden was higher in those with severe reaction (median 0.018% [n = 207] in Grade 3–4 vs. 0.001% [n = 78] in Grade 1–2; p <.0001), and the majority had normal baseline serum tryptase levels (69% [n = 196 of 285]). All KIT p.D816V‐positive individuals (n = 41) who underwent bone marrow (BM) biopsy were found to have underlying clonal diseases, principally BM mastocytosis. HαT was also associated with severe HVA and symptoms (p <.01), and remarkably, 31.0% (n = 31 of 100) were found to have concomitant KIT p.D816V. Concomitant HαT and KIT p.D816V showed an additive effect, and having both was associated with the highest risk for severe HVA, even higher than having either HαT or KIT p.D816V alone (OR = 3.8; p <.01). Conclusions: By employing prospective universal tryptase genotyping and examination for KIT p.D816V in PBL in large HVA populations, we have demonstrated a high burden of clonal MC disorders and HαT in patients who require VIT. [ABSTRACT FROM AUTHOR]

Vanadium is a strategic metal that has many important industrial applications and is generated by the use of burning fossil fuels, which inevitably leads to their release into the environment, mainly in the form of oxides. The wastes generated by their use represent a major health hazard. Furthermore, it has attracted attention because several genotoxicity studies have shown that some vanadium compounds can affect DNA; among the most studied compounds is vanadium pentoxide, but studies in vivo with oxidation states IV and III are scarce and controversial. In this study, the genotoxic and cytotoxic potential of vanadium oxides was investigated in mouse bone marrow cells using structural chromosomal aberration (SCA) and mitotic index (MI) test systems. Three groups were administered vanadium(IV) tetraoxide (V2O4) intraperitoneally at 4.7, 9.4 or 18.8 mg/kg, and three groups were administered vanadium(III) trioxide (V2O3) at 4.22, 8.46 or 16.93 mg/kg body weight. The control group was treated with sterile water, and the positive control group was treated with cadmium(II) chloride (CdCl2). After 24 h, all doses of vanadium compounds increased the percentage of cells with SCA and decreased the MI. Our results demonstrated that under the present experimental conditions and doses, treatment with V2O4 and V2O3 induces chromosomal aberrations and alters cell division in the bone marrow of mice. [ABSTRACT FROM AUTHOR]

Purpose: Bone marrow stimulation is a common treatment for full‐thickness cartilage defects in the hip joint. However, common procedures may result in poor fibrous repair tissue and changes to the subchondral anatomy. This study investigated the clinical outcome of a cohort of International Cartilage Repair Society (ICRS) grades 3 and 4 cartilage defects treated with bone marrow stimulation compared to those who received simple debridement/chondroplasty. Methods: In this retrospective registry study, 236 patients with uni‐focal acetabular chondral lesions of the hip up to 400 mm² (mean 177.4 ± 113.4 mm²) and of ICRS grade ≥3 with follow‐up of at least 12 months (mean 33.2 ± 15.3 months) were included. Eighty‐one patients underwent bone marrow stimulation (microfracture: n = 44, abrasion: n = 37) besides treatment of the underlying pathology, 155 patients underwent defect debridement/chondroplasty. The patient‐reported outcome was measured using the International Hip Outcome Tool 33 (iHOT33) score and the Visual Analogue Scale (VAS) for pain. Results: iHOT33 and VAS both improved highly statistically significantly (p < 0.001) in the debridement group after 6, 12, 24, 36 and 60 months compared to the preoperative scores, whereas iHOT33 and VAS after microfracture or abrasion did not show statistically significant changes over time. Twenty‐four and sixty months postsurgery the debridement group revealed significant higher scores in the iHOT33 compared to the bone marrow stimulation groups. Conclusion: Patients with chondral lesions of the hip ≤400 mm2 sustainably benefit from arthroscopic debridement under preservation of the subchondral bone plate in terms of functional outcome and pain in contrast to patients treated with bone marrow stimulation. These findings discourage the currently recommended use of microfracture in the hip joint. Level of Evidence: Level III. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to study the effects of the severity of preoperative bone marrow oedema (BME) on the postoperative short‐term outcomes following bone marrow stimulation (BMS) for osteochondral lesions of the talus (OLTs) and to propose a new metric that combines volume and signal density to evaluate BME. Methods: Sixty‐five patients with symptomatic OLTs (<100 mm2) and preoperative BME, who received BMS in our institution from April 2017 to July 2021 with follow‐ups of 3, 6 and 12 months, were analysed retrospectively. The area, volume and signal value of the BME were collected on preoperative magnetic resonance imaging. The enroled patients were divided into two groups according to the BME index (BMEI), which was defined as the product of oedema relative signal intensity and the relation of oedema volume to total talar volume. Visual analogue scale, American Orthopedic Foot and Ankle Society (AOFAS), Tegner, Foot and Ankle Ability Measure (FAAM)–activities of daily living (ADL) and Sports scores were assessed before surgery and at each follow‐up. The relationship between the scores and the volume, relative signal intensity and BMEI was explored. Results: Sixty‐five patients with preoperative BME were divided into the mild (n = 33) and severe (n = 32) groups based on the BMEI. A significant difference was found for each score with the general linear model for repeated measures through all follow‐up time points (p < 0.001). For the preoperative and 12‐month postoperative changes of the enroled patients, 53 patients (81.5%) exceeded the minimal clinically important difference of AOFAS and 26 (40.0%) exceeded that of FAAM‐sports in this study. The mild group showed significantly more improvement in AOFAS scores at 12 months (89.6 ± 7.0 vs. 86.2 ± 6.2) and FAAM‐ADL scores at 6 months (83.6 ± 7.6 vs. 79.7 ± 7.7) and 12 months (88.5 ± 8.5 vs. 84.4 ± 7.7) than the severe group (p < 0.05). No significant difference of all the scores between the groups was found at 3 months. No significant correlation was found in each group between BMEI and clinical outcomes. Conclusion: The severity of the preoperative BME negatively affected short‐term clinical outcomes following arthroscopic BMS for OLTs. Worse clinical outcomes were shown at postoperative 6 and 12 months in patients with a high preoperative BMEI, which could be a favourable parameter for assessing the severity of BME and assist in developing personalised rehabilitation plans and determining the approach and timing of surgery. Level of Evidence: Level III. [ABSTRACT FROM AUTHOR]

Purpose: Meniscal wrapping is a fully arthroscopic technique that involves enhanced meniscal repair with a tissue-engineered collagen matrix wrapping. This study aims to investigate the feasibility of using the meniscal wrapping technique for the treatment of chronic or complex meniscal tears. The primary objective is to assess its failure rate. The secondary objectives are to analyse complication rate, functional outcomes and overall patient satisfaction. Methods: This retrospective case series study included patients who sustained chronic and complex tears undergoing meniscal wrapping with autologous liquid bone marrow injection. Failure rate was considered if the patient underwent partial or complete meniscectomy or knee replacement during the follow-up, while other unexpected knee reoperations were considered as complications. Clinical outcomes were evaluated through the IKDC score, Tegner Activity Score and Short Assessment of Patient Satisfaction. Results: Twenty-one patients were included (15 non-acute bucket-handle tears, three non-acute horizontal tears and three non-acute complex injuries). The failure rate was 9.5% at 33 months. The rate of other unplanned reoperations was 14.3%, but none of these complications were apparently directly related to the wrapping technique. The average postoperative IKDC was 73.3/100. No statistically significant difference was encountered between preinjury and postoperative Tegner Activity Score. The mean overall patient satisfaction was 88.3/100. Conclusions: Meniscal wrapping can be safely used as an adjunctive technique to meniscal repair in such difficult-to-treat cases to preserve the meniscus. The technique achieves a low failure rate and promising results of knee function, and patient satisfaction. [ABSTRACT FROM AUTHOR]

IgG4-related diseases (IgG-RDs) are a group of fibroinflammatory diseases that affect a variety of tissues, resulting in tumour-like effects and/or organ dysfunction. Monoclonal gammopathies (MGPs) are a group of disorders characterized by clonal proliferation of plasma cells or lymphoid cells resulting in the secretion of a monoclonal immunoglobulin. Cases of MGPs in IgG4-RDs coexisting with plasma cell dyscrasias and lymphoid neoplasms have been reported over the past few years. Therefore, the results of examinations of M protein in IgG4-RD patients should be interpreted with caution. Herein, we report the case of a 58-year-old male with a history of type 2 diabetes who presented with submandibular masses, anosmia, swollen lymph nodes, proteinuria, and renal impairment. Laboratory tests revealed hyperglobulinemia and elevated levels of IgG4 (124 g/L) and serum-free light chains (sFLCs). Serum protein electrophoresis (SPEP) revealed an M spike of 5.6 g/dL, and immunofixation electrophoresis (IPE) revealed biclonal IgG-κ and IgG-λ. The patient underwent bone marrow, lymph node, and kidney biopsy, which ruled out plasma cell disorders and lymphoma. He was finally diagnosed with an IgG4-RD comorbid with diabetic nephropathy. The findings in this case highlight that significant activation of B cells in IgG4-RD patients, especially those with multiorgan involvement can lead to significant hyperglobulinemia and high sFLC and IgG4 levels, which are more pronounced in the setting of renal impairment. Relatively high concentrations of polyclonal IgG4 can give rise to a focal band bridging the β and γ fractions, which may mimic the appearance of a monoclonal band on SPEP and monoclonal gammaglobulinemia in IFE. The patient experienced considerable improvement in his symptoms after rituximab combined with glucocorticoid therapy, and a monoclonal immunoglobulin was not detected. [ABSTRACT FROM AUTHOR]

In musculoskeletal imaging, CT is used in a wide range of indications, either alone or in a synergistic approach with MRI. While MRI is the preferred modality for the assessment of soft tissues and bone marrow, CT excels in the imaging of high-contrast structures, such as mineralized tissue. Additionally, the introduction of dual-energy CT in clinical practice two decades ago opened the door for spectral imaging applications. Recently, the advent of photon-counting detectors (PCDs) has further advanced the potential of CT, at least in theory. Compared to conventional energy-integrating detectors (EIDs), PCDs provide superior spatial resolution, reduced noise, and intrinsic spectral imaging capabilities. This review briefly describes the technical advantages of PCDs. For each technical feature, the corresponding applications in musculoskeletal imaging will be discussed, including high-spatial resolution imaging for the assessment of bone and crystal deposits, low-dose applications such as whole-body CT, as well as spectral imaging applications including the characterization of crystal deposits and imaging of metal hardware. Finally, we will highlight the potential of PCD-CT in emerging applications, underscoring the need for further preclinical and clinical validation to unleash its full clinical potential. [ABSTRACT FROM AUTHOR]

Higher-risk myelodysplastic syndromes (HR-MDS) are defined using a number of prognostic scoring systems that include the degree of cytopenias, percentage of blasts, cytogenetic alterations, and more recently genomic data. HR-MDS encompasses characteristics such as progressive cytopenias, increased bone marrow blasts, unfavorable cytogenetics, and an adverse mutational profile. Survival is generally poor, and patients require therapy to improve outcomes. Hypomethylating agents (HMAs), such as azacitidine, decitabine, and more recently, oral decitabine/cedazuridine, are the only approved therapies for HR-MDS. These are often continued until loss of response, progression, or unacceptable toxicity. Combinations including an HMA plus other drugs have been investigated but have not demonstrated better outcomes compared to single-agent HMA. Moreover, in a disease of high genomic complexity such as HR-MDS, therapy targeting specific genomic abnormalities is of interest. This review will examine the biological underpinnings of HR-MDS, its therapeutic landscape in the frontline and relapsed settings, as well as the impact of hematopoietic stem cell transplantation, the only known curative intervention for this disease. [ABSTRACT FROM AUTHOR]

Mesenchymal stromal cells (MSCs) are attractive as a therapeutic modality in multiple disease conditions characterized by inflammation and vascular compromise. Logistically they are advantageous because they can be isolated from adult tissue sources, such as bone marrow (BM). The phase 2a START clinical trial determined BM-MSCs to be safe in patients with moderate-to-severe acute respiratory distress syndrome (ARDS). Herein, we examine a subset of the clinical doses of MSCs generated for the phase 2a START trial from three unique donors (1–3), where one of the donors' donated BM on two separate occasions (donor 3 and 3W). The main objective of this study was to correlate properties of the cells from the four lots with plasma biomarkers from treated patients and relevant to ARDS outcomes. To do this we evaluated MSC donor lots for (i) post-thaw viability, (ii) growth kinetics, (iii) metabolism, (iv) surface marker expression, (v) protein expression, (vi) immunomodulatory ability and (vii) their functional effects on regulating endothelial cell permeability. MSC-specific marker expression and protection of thrombin-challenged endothelial barrier permeability was similar among all four donor lots. Inter and intra-donor variability was observed in all the other in vitro assays. Furthermore, patient plasma ANG-2 and protein C levels at 6 hours post-transfusion were correlated to cell viability in an inter- and intra-donor dependent manner. These findings highlight the potential of donor dependent (inter-) and collection dependent (intra-) effects in patient biomarker expression. [ABSTRACT FROM AUTHOR]

The selenized modification of purified Pleurotus eryngii polysaccharides (PPEP) were carried out in a nitric acid-sodium selenite system, and the preliminary structural characterization of PPEP and selenized PPEP (613.87 μg/g of selenium) (SPPEP) were carried out by advanced instrumentation techniques. It was found that the selenization modification did not seriously affect the structure of the PPEP. However, the SPPEP exhibited a lower molecular weight, more glycosidic bonds, reduced crystallinity, and improved thermal stability. Through in vivo animal experiments, the study found that PPEP and SPPEP were non-toxic to macrophages. Furthermore, they markedly increased the thymus and spleen indices of immunocompromised mice and improved the histomorphology of these organs. Moreover, PPEP and SPPEP enhanced the mice's immune ability by markedly increasing the level of immune factor secretion, bone marrow hematopoietic function, and macrophage phagocytic capacity. In addition, the immune activity of SPPEP was better than PPEP's activity. [Display omitted] • The polysaccharide of P.eryngii is selenized for the first time. • The selenization modification did not seriously affect the structure of the PPEP. • The immune activity of SPPEP is better than PPEP's activity. • Selenide polysaccharides were evaluated for non-toxicity. [ABSTRACT FROM AUTHOR]

Sacroiliitis is commonly seen in patients with axial spondyloarthritis, in whom timely diagnosis and treatment are crucial to prevent irreversible structural damage. Imaging has a prominent place in the diagnostic process and several new imaging techniques have been examined for this purpose. We present a summary of updated evidence-based practice recommendations for imaging of sacroiliitis. MRI remains the imaging modality of choice for patients with suspected sacroiliitis, using at least four sequences: coronal oblique T1-weighted and fluid-sensitive sequences, a perpendicular axial oblique sequence, and a sequence for optimal evaluation of the bone-cartilage interface. Both active inflammatory and structural lesions should be described in the report, indicating location and extent. Radiography and CT, especially low-dose CT, are reasonable alternatives when MRI is unavailable, as patients are often young. This is particularly true to evaluate structural lesions, at which CT excels. Dual-energy CT with virtual non-calcium images can be used to depict bone marrow edema. Knowledge of normal imaging features in children (e.g., flaring, blurring, or irregular appearance of the articular surface) is essential for interpreting sacroiliac joint MRI in children because these normal processes can simulate disease. Clinical relevance statement: Sacroiliitis is a potentially debilitating disease if not diagnosed and treated promptly, before structural damage to the sacroiliac joints occurs. Imaging has a prominent place in the diagnostic process. We present a summary of practice recommendations for imaging of sacroiliitis, including several new imaging techniques. Key Points: • MRI is the modality of choice for suspected inflammatory sacroiliitis, including a joint-line-specific sequence for optimal evaluation of the bone-cartilage interface to improve detection of erosions. • Radiography and CT (especially low-dose CT) are reasonable alternatives when MRI is unavailable. • Knowledge of normal imaging features in children is mandatory for interpretation of MRI of pediatric sacroiliac joints. [ABSTRACT FROM AUTHOR]

Primary myelofibrosis (PMF) is the most aggressive of the myeloproliferative neoplasms and patients require greater attention and likely require earlier therapeutic intervention. Currently approved treatment options are limited in their selective suppression of clonal proliferation resulting from driver- and coexisting gene mutations. Janus kinase inhibitors are approved for symptomatic patients with higher-risk PMF. Additionally, most ongoing clinical studies focus on patients with higher-risk disease and/or high rates of transfusion dependency. Optimal treatment of early/lower-risk PMF remains to be identified and needs randomized clinical trial evaluations. Pegylated interferon alfa is recommended for symptomatic lower-risk PMF patients based on phase 2 non-randomized studies and expert opinion. Ropeginterferon alfa-2b (ropeg) is a new-generation pegylated interferon-based therapy with favorable pharmacokinetics and safety profiles, requiring less frequent injections than prior formulations. This randomized, double-blind, placebo-controlled phase 3 trial will assess its efficacy and safety in patients with "early/lower-risk PMF", defined as pre-fibrotic PMF or PMF at low or intermediate-1 risk according to Dynamic International Prognostic Scoring System-plus. Co-primary endpoints include clinically relevant complete hematologic response and symptom endpoint. Secondary endpoints include progression- or event-free survival, molecular response in driver or relevant coexisting gene mutations, bone marrow response, and safety. Disease progression and events are defined based on the International Working Group criteria and well-published reports. 150 eligible patients will be randomized in a 2:1 ratio to receive either ropeg or placebo. Blinded sample size re-estimation is designed. Ropeg will be administered subcutaneously with a tolerable, higher starting-dose regimen. The study will provide important data for the treatment of early/lower-risk PMF for which an anti-clonal, disease-modifying agent is highly needed. [ABSTRACT FROM AUTHOR]

Amyloid Light Chain (AL) Amyloidosis is a rare disorder of protein misfolding and metabolism characterized by insoluble fibrils deposition in various tissues and organs, which could quickly progress and become fatal. The most frequently affected organ is heart being its involvement the most adverse prognostic feature. Kidney and liver could be other organ localizations, defining AL Amyloidosis as a multisystem disorder. Being Budd-Chiari syndrome (BCS) an uncommon congestive hepatopathy caused by blockage of hepatic veins in the absence of cardiac disorders, it could be rarely caused by a massive deposition of amyloid proteins into hepatic sinusoidal spaces, giving an uncommon clinical presentation of AL Amyloidosis. [ABSTRACT FROM AUTHOR]

Purpose: To study the biochemical analysis of aqueous humor in a patient with multiple myeloma presenting first as chronic uveitis. Methods: Observational case report. Results: A 63-year-old healthy woman presented with blurred vision in both eyes for 9 months. Slit-lamp examination showed bilateral conjunctival congestion, corneal oedema, and anterior uveitis. Fundus exam revealed normal optic disc with fine retinal folds in the macula. Serum protein electrophoretogram showed a monoclonal M protein band in the gamma globulin region. The bone marrow biopsy revealed hypercellular marrow with trilineage haematopoiesis and the bone marrow aspirate showed clonal plasma cells >10%, confirming the diagnosis of multiple myeloma. Aqueous fluid showed a differential band in electrophoretic profile of aqueous humor protein that on mass spectrometry analysis was strongly suggestive of immunoglobulin band. Conclusion: The biochemical analysis of aqueous humor is another diagnostic test to monitor M protein in patients with multiple myeloma. [ABSTRACT FROM AUTHOR]

Background/Aim: Bone marrow cells contain nonhematopoietic cells with the ability to differentiate into osteogenic, chondrogenic, and adipogenic lineages. Mechanical stress influences osteoblast differentiation of bone marrow cells into osteogenic, chondrogenic, and adipogenic lineages, measurable as the abundance of alkaline phosphatase-positive (ALP+) colony-forming unit-fibroblasts (CFU-F); however, the effect of diode laser irradiation on osteoblast differentiation is unknown. The aim of this study was to analyze the effects of photobiomodulation on the osteogenic differentiation of mesenchymal stem cells in the bone marrow, using the CFU-F assay. Materials and Methods: Bone marrow cells isolated from rat tibiae were cultured and irradiated with a diode laser (wavelength 808 nm) at a total energy of 0 J (control), 50 J, and 150 J. Results: On day 7 after irradiation, ALP+ CFU-F were most abundant in the 50 J group and the least abundant in the 150 J group. Mineralized nodule formation was observed after long-term culture (21 days). Compared with the control group, there were significantly more nodules in the 50 J group and significantly fewer nodules in the 150 J group. Osteocalcin mRNA expression was highest in the 50 J group, and there was no difference between the control and 150 J groups. Conclusion: Irradiation with 50 J was effective in stimulating osteogenesis in bone marrow stem cells. These findings suggest that diode laser irradiation can induce osteogenesis in rat bone marrow cells in an energy-dependent manner, and appears suitable for application in bone regeneration therapy. [ABSTRACT FROM AUTHOR]

During the development of leukemia, the overgrowth of leukemia cells in the bone marrow transforms the normal hematopoietic microenvironment into the leukemia microenvironment which favors its growth and inhibits normal hematopoietic stem cells. The leukemia microenvironment exhibits abnormalities in redox substances, metabolism, immune response, mesenchymal cells, extracellular matrix, stromal cells, hypoxia, and more. These factors collectively provide a shelter for the malignant proliferation of leukemia cells. Recently, as the understanding of the leukemia microenvironment deepens, targeting or remodeling the abnormal leukemia microenvironment is becoming an effective strategy for leukemia treatment. Nanomedicine technology can effectively change pharmacokinetic profiles, thus demonstrating many advantages in modulating the leukemia microenvironment and improving therapeutic selectivity. In this review, we outline the characteristics of abnormal leukemia bone marrow microenvironment, focusing on the abnormal changes in the redox, metabolic and immune microenvironment. We also summarize emerging nanotechnology strategies in remodeling or targeting the aforementioned abnormal microenvironment. In addition, the unique advantages and bright prospects of nanotechnology in remodeling and targeting the leukemia microenvironment are discussed. [ABSTRACT FROM AUTHOR]

Background: Axial spondyloarthritis (axSpA) is a group of inflammatory diseases that may lead to ankylosis of the sacroiliac joint and spine. Fat lesion in the sacroiliac joint is an important feature in diagnosis and disease progression of axSpA. However, whether there is alteration of fatty acids (FAs) composition has not been investigated using MRI. Purpose: To investigate bone marrow FA composition of the sacroiliac joint in patients with axSpA compared to controls. Study Type: Prospective. Subjects: Eighty five participants (mean age, 32.3 ± 6.1 years): 48 axSpA (25 male, 23 female) and 37 non‐SpA controls (18 male, 19 female). Field Strength/Sequence: 3.0 T/Two multiple gradient‐echo chemical shift‐encoded (CSE) MRI which differed only in echo times (TEs) were scanned consecutively. Assessment: Axial multi‐echo CSE MRI was performed in the sacroiliac joints in vivo. Regions of interest (ROIs) were manually placed on subchondral bone with and without fat lesion in axSpA patients, and on subchondral bone without fat lesion in controls. FA composition was computed within the ROIs using a nonlinear least square method from literature. Statistical Tests: Intergroup comparisons were performed using t tests. Results: In axSpA, male patients had significantly higher monounsaturated FA compared to controls in areas with fat lesion in the sacrum (+12%) and in the ilium (+9%), and in areas without fat lesion in the sacrum (+10%). Significantly lower polyunsaturated FAs were found in areas with fat lesion in the sacrum (−10%) and ilium (−11%), and lower saturated FAs were found in areas without fat lesion in the sacrum (−6%). In female, patients with axSpA had significantly higher saturated FAs in areas with fat lesion in the ilium (+7%) in comparison to controls. Data Conclusion: FA composition of the sacroiliac joint alters in patients with axSpA, and it can be detected using CSE MRI based analysis. [ABSTRACT FROM AUTHOR]

Improvements in therapies for heart failure with preserved ejection fraction (HFpEF) are crucial for improving patient outcomes and quality of life. Although HFpEF is the predominant heart failure type among older individuals, its prognosis is often poor owing to the lack of effective therapies. The roles of the spleen and bone marrow are often overlooked in the context of HFpEF. Recent studies suggest that the spleen and bone marrow could play key roles in HFpEF, especially in relation to inflammation and immune responses. The bone marrow can increase production of certain immune cells that can migrate to the heart and contribute to disease. The spleen can contribute to immune responses that either protect or exacerbate heart failure. Extramedullary hematopoiesis in the spleen could play a crucial role in HFpEF. Increased metabolic activity in the spleen, immune cell production and mobilization to the heart, and concomitant cytokine production may occur in heart failure. This leads to systemic chronic inflammation, along with an imbalance of immune cells (macrophages) in the heart, resulting in chronic inflammation and progressive fibrosis, potentially leading to decreased cardiac function. The bone marrow and spleen are involved in altered iron metabolism and anemia, which also contribute to HFpEF. This review presents the concept of an interplay between the heart, spleen, and bone marrow in the setting of HFpEF, with a particular focus on extramedullary hematopoiesis in the spleen. The aim of this review is to discern whether the spleen can serve as a new therapeutic target for HFpEF. [ABSTRACT FROM AUTHOR]

Objectives : This study aimed to analyze the efficacy of stem cell-based tissue engineering for the treatment of alveolar cleft (AC) and cleft palate (CP) defects in animal models. Design : Systematic review and meta-analysis. Setting : Preclinical studies on alveolar cleft repair in maxillofacial practice. Patients, Participants : Electronic search was performed using PubMed, Embase, and Cochrane databases. Pre-clinical studies, where stem cell-based tissue engineering was used in the reconstruction of AC and CP in animal models were included. Quality of the selected articles was evaluated using SYRCLE (SYstematic Review Centre for Laboratory animal Experimentation). Interventions : Review of alveolar cleft bone augmentation interventions in preclinical models. Main Outcome Measures : Outcome parameters registered were new bone formation (NBF) and/or bone mineral density (BMD). Results : Thirteen large and twelve small animal studies on AC (21) and CP (4) reconstructions were included. Studies had an unclear-to-high risk of bias. Bone marrow mesenchymal stem cells were the most widely used cell source. Meta-analyses for AC indicated non-significant benefits in favor of: (1) scaffold + cells over scaffold-only (NBF P =.13); and (2) scaffold + cells over empty control (NBF P =.66; BMD P =.31). Interestingly, dog studies using regenerative grafts showed similar to superior bone formation compared to autografts. Meta analysis for the CP group was not possible. Conclusions : AC and CP reconstructions are enhanced by addition of osteogenic cells to biomaterials. Directions and estimates of treatment effect are useful to predict therapeutic efficacy and guide future clinical trials of bone tissue engineering. [ABSTRACT FROM AUTHOR]

Background: Epstein–Barr virus-positive mucocutaneous ulcer is one of the mature B-cell lymphoproliferative diseases occurring in patients with immune dysfunction including those with immunosuppressive treatment such as methotrexate. Case presentation: A Japanese elderly man in his 80s with rheumatoid arthritis on methotrexate was admitted to our hospital complaining persistent pharyngeal pain. Laboratory tests revealed severe pancytopenia, elevated C-reactive protein, and increased creatinine levels. An otolaryngological examination showed ulceration of the right tonsil, from which diagnostic biopsy was performed. The diagnosis of Epstein–Barr virus-positive mucocutaneous ulcer was made and bone marrow aspiration revealed hypocellularity and megaloblastic changes. Pancytopenia was improved after discontinuing methotrexate, and repeated bone marrow aspiration test revealed recovery of normal cellularity and disappearance of dysplasia, confirming the diagnosis of methotrexate intoxication. Tonsil ulcer was improved only with discontinuation of methotrexate, which strongly supported the diagnosis of EBV-MCU. Conclusion: Our case suggested that even this best prognosis form of lymphoproliferative disease could lead to fatal complications if not appropriately managed. [ABSTRACT FROM AUTHOR]

Background: Orthopedic procedures often require removing bone or pathological tissue, with traditional methods involving instruments like curettes and rongeurs. However, these methods can be time-consuming and lead to increased blood loss. To mitigate these side effects, vacuum-assisted tools have been developed to aid in tissue removal. These devices enable surgeons to suction tissue without discarding it, potentially improving outcomes in conditions such as osteomyelitis or tumor removal while enabling collection of the material for downstream applications. Despite limited research, vacuum-assisted devices show promise beyond bone marrow harvesting. This study assesses infection and clearance rates, estimated blood loss, and total procedure time associated with the use of vacuum-assisted tissue removal, with a goal to understand if these devices can be used for tissue removal across a variety of pathologic conditions. Methods: A retrospective cohort study was conducted on patients undergoing orthopedic procedures with the Avitus® Bone Harvester repurposed from its original design from December 1, 2021, to July 1, 2023. Procedures were categorized into oncology, and debridement for infection cases. Infection cases were further categorized into those secondary to trauma and those involving primary infections (osteomyelitis and periprosthetic joint infection). Clinical variables, including demographics, intraoperative details, complications, and follow-up, were reviewed. Statistical analysis included descriptive statistics computed with R Studio. Results: The study included 44 patients, with debridement for infection cases being the most common (primary infection: 45.5%; infection secondary to trauma: 18.1%), followed by oncology cases (36.4%). In all oncology cases, a definitive diagnosis was established using the device, and no post-operative infections were reported. The infection clearance rate was 85.0% for primary infection cases and 50.0% for cases of infection following trauma. Across the entire cohort, the average blood loss was 314.52 mL (sd: 486.74), and the average total procedure time was 160.93 min (sd: 91.07). The overall reoperation rate was 47.7%, with an unplanned reoperation rate of 11.4%. Conclusion: The vacuum-assisted bone harvester was effectively utilized in a wide range of debridement and curettage procedures across diverse orthopedic surgeries. In oncology cases, the device enabled effective tissue removal with comparable recurrence rates, demonstrating its potential to minimize contamination while preserving tissue for accurate diagnoses. Additionally, a high rate of osteomyelitis eradication was observed in debridement for primary infection cases (85%). Despite the relatively high reoperation rate of 47.7%, it is crucial to interpret this figure within the context of the varied reasons for reoperation. Many of these reoperations were planned as part of a staged approach to treatment or were unrelated to the device's performance. It is crucial to acknowledge that isolating the device's contribution to these results can be difficult. The utilization of the device should be guided by considerations of cost-effectiveness and patient-specific risk factors. [ABSTRACT FROM AUTHOR]

Summary Bone marrow endothelial progenitor cells (BM EPCs) are crucial in supporting haematopoietic regeneration, while the BM EPCs of haematological patients with chemotherapy‐induced thrombocytopenia (CIT) are unavoidably damaged. Therefore, the present study aimed to examine the effect of thrombopoietin (TPO) on the recovery of BM EPCs of CIT patients and to identify the underlying mechanisms. The cell functions were determined by 1,1‘‐dioctadecyl‐3,3,3’,3‘‐tetramethylindocarbocyanine perchlorate (Dil)–acetylated low‐density lipoprotein (Dil‐Ac‐LDL) uptake and fluorescein isothiocyanate (FITC)‐labeled Ulex europaeus agglutinin‐I (FITC‐UEA‐I) binding assay, as well as proliferation, migration and tube formation experiments. Endothelial cells were transfected with METTL16 lentivirus, followed by methylated RNA immunoprecipitation sequencing. Zebrafish with vascular defect was used as the in vivo model. TPO significantly improved the quantity and functions of BM EPCs from CIT patients in vitro and restored the subintestinal vein area of zebrafish with vascular defect in vivo. Mechanically, TPO enhanced the BM EPC functions through Akt signal mediated by METTL16, which was downregulated in BM EPCs of CIT patients and involved in the regulation of endothelial functions. The present study demonstrates that TPO improves the recovery of BM EPCs from CIT patients with haematological malignancies via METTL16/Akt signalling, which provides new insights into the role of TPO in treating CIT in addition to direct megakaryopoiesis. [ABSTRACT FROM AUTHOR]

Summary Addition of molecular data to prognostic models has improved risk stratification of myelodysplastic neoplasms (MDS). However, the role of molecular lesions, particularly in the group of low‐risk disease (LR‐MDS), is uncertain. We evaluated a set of 227 patients with LR‐MDS. Overall survival (OS) and probability of leukaemic progression were the main endpoints. RUNX1 was associated with lower OS and SF3B1 with a reduced risk of death (HR: 1.7, 95% CI, 1.1–2.9; p = 0.05; and HR: 0.23, 95% CI 0.1–0.5; p < 0.001; respectively). TP53 and RUNX1 mutations were predictive covariates for the probability of leukaemic progression (p < 0.001). Blast percentage, neither analysed as categorical (<5% vs. 5%–9%; HR: 1.3, 95% CI, 0.7–2.9; p = 0.2) nor as a continuous variable (HR: 1.07, 95% CI, 0.9–1.1; p = 0.07), had impact on survival or probability of progression (sHR: 1.05, 95% CI, 0.9–1.1; p = 0.2). These results retained statistical significance when analysis was restricted to the definition of LR‐MDS according to the WHO 2022 and ICC classifications (<5% blasts). Thus, with the incorporation of molecular data, blast percentage happens to lose clinical significance both for survival and probability of progression in the group of patients with LR‐MDS. [ABSTRACT FROM AUTHOR]

Purpose: For women with locoregionally advanced cervical cancer, the standard of care treatment is the curatively intended chemoradiation therapy (CRT). A relationship between bone marrow (BM) dose–volume histograms (DVHs) and acute hematological toxicity (HT) has been debated recently. Aim of this study was the evaluation of BM dose constraints and HT in a contemporary patient cohort. Methods: Radiation treatment plans of 31 patients with cervical cancer (FIGO stage IIB–IVB) treated with intensity-modulated radiotherapy and simultaneous chemotherapy were explored retrospective. Pelvic bones (PB) and femoral heads (FH) were contoured and DVHs were correlated with white blood cells (WBC), hemoglobin levels and platelets. Results: Comparing the absolute blood levels with the dose volumes of both FH and PB the data showed a significant correlation between WBC and the median dose of the FH and the median dose, V30Gy, V40Gy and V50Gy of the PB. A correlation between the toxicity grade of anemia and mean dose, maximum dose and V5Gy of the PB was found. Counting the highest grade of HT of all three blood levels of each patient, significant correlations were found for the mean and median dose, V30Gy, V40Gy and V50Gy of the PB. Conclusion: The results show that blood levels may correlate with distinct dosimetric subvolumes of critical bone marrow compartments with a potential impact on therapeutic outcome and treatment-related toxicity. The data presented are in line with the previous findings on the relevance of dosimetric exposure of pelvic bony subvolumes. [ABSTRACT FROM AUTHOR]

Acute lymphoblastic leukemia (ALL) is a prevalent malignancy affecting the hematopoietic system, encompassing both B-cell ALL (B-ALL) and T-cell ALL (T-ALL). T-ALL, characterized by the proliferation of T-cell progenitors in the bone marrow, presents significant treatment challenges, with patients often experiencing high relapse rates and poor long-term survival despite advances in chemotherapy and hematopoietic stem cell transplantation (HSCT). This review explores the pathogenesis and traditional treatment strategies of T-ALL, emphasizing the promising potential of chimeric antigen receptor (CAR) technology in overcoming current therapeutic limitations. CAR therapy, leveraging genetically modified immune cells to target leukemia-specific antigens, offers a novel and precise approach to T-ALL treatment. The review critically analyzes recent developments in CAR-T and CAR-NK cell therapies, their common targets, optimization strategies, clinical outcomes, and the associated challenges, providing a comprehensive overview of their clinical prospects in T-ALL treatment. [ABSTRACT FROM AUTHOR]

Bone marrow stromal cells (BMSCs) play a significant role in bone metabolism as they can differentiate into osteoblasts, bone marrow adipocytes (BMAds), and chondrocytes. BMSCs chronically exposed to nutrient overload undergo adipogenic programming, resulting in bone marrow adipose tissue (BMAT) formation. BMAT is a fat depot transcriptionally, metabolically, and morphologically distinct from peripheral adipose depots. Reactive oxygen species (ROS) are elevated in obesity and serve as important signals directing BMSC fate. ROS produced by the NADPH oxidase (NOX) family of enzymes, such as NOX4, may be responsible for driving BMSC adipogenesis at the expense of osteogenic differentiation. The dual nature of ROS as both cellular signaling mediators and contributors to oxidative stress complicates their effects on bone metabolism. This review discusses the complex interplay between ROS and BMSC differentiation in the context of metabolic bone diseases.Special attention is paid to the role of NOX4-ROS in regulating cellular processes within the bone marrow microenvironment and potential target in metabolic bone diseases. [ABSTRACT FROM AUTHOR]

An aged immune system undergoes substantial changes where myelopoiesis dominates within the bone marrow. Monocytic‐MDSCs (M‐MDSCs) have been found to play an important role in osteoclastogenesis and bone resorption. In this study, we sought to provide a more comprehensive understanding of the osteoclastogenic potential of bone marrow M‐MDSCs during normal aging through transcriptomic and metabolic changes. Using young mature and aged mice, detailed immunophenotypic analyses of myeloid cells revealed that the M‐MDSCs were not increased in bone marrow, however M‐MDSCS were significantly expanded in peripheral tissues. Although aged mice exhibited a similar number of M‐MDSCs in bone marrow, these M‐MDSCs had significantly higher osteoclastogenic potential and greater demineralization activity. Intriguingly, osteoclast progenitors from aged bone marrow M‐MDSCs exhibited greater mitochondrial respiration rate and glucose metabolism. Further, transcriptomic analyses revealed the upregulation of mitochondrial oxidative phosphorylation and glucose metabolism genes. Interestingly, there was 8‐fold increase in Cd38 mRNA gene expression, consistent with the Mouse Aging Cell Atlas transcriptomic database, and confirmed by qRT‐PCR. CD38 regulates NAD+ availability, and 78c, a small molecule inhibitor of CD38, reduced the mitochondrial oxygen consumption rate and glucose metabolism and inhibited the osteoclastogenic potential of aged mice bone marrow‐derived M‐MDSCs. These results indicate that the age‐related increase in Cd38 expression in M‐MDSCs bias the transcriptome of M‐MDSCs towards osteoclastogenesis. This enhanced understanding of the mechanistic underpinnings of M‐MDSCs and their osteoclastogenesis during aging could lead to new therapeutic approaches for age‐related bone loss and promote healthy aging. [ABSTRACT FROM AUTHOR]

Visceral leishmaniasis (VL) is a neglected tropical disease caused by parasites from the Leishmania (L.) donovani complex. VL is characterised by uncontrolled parasite replication in spleen, liver and bone marrow, and by an impaired immune response and high systemic levels of inflammation. Monocytes have been poorly characterised in VL patients. The aim of this study was to evaluate the expression levels of markers involved in the regulation of T cell responses on different subsets of monocytes from the blood of VL patients and healthy non-endemic controls (HNEC). Monocytes can broadly be divided into three subsets: classical, intermediate and non-classical monocytes. Our results show that the percentages of all three subsets stay similar at the time of VL diagnosis (ToD) and at the end of anti-leishmanial treatment (EoT). We first looked at co-stimulatory receptors: the expression levels of CD40 were significantly increased on classical and intermediate, but not non-classical monocytes, at ToD as compared to EoT and HNEC. CD80 expression levels were also increased on intermediate monocytes at ToD as compared to EoT and HNEC, and on classical monocytes only as compared to HNEC. The levels of CD86 were similar at EoT and ToD and in HNEC on classical and intermediate monocytes, but significantly higher at EoT on non-classical monocytes. We also looked at an inhibitory molecule, PD-L1. Our results show that the expression levels of PD-L1 is significantly higher on all three monocyte subsets at ToD as compared to HNEC, and to EoT on classical and intermediate monocytes. These results show that monocytes from the blood of VL patients upregulate both co-stimulatory and inhibitory receptors and that their expression levels are restored at EoT. Author summary: Visceral leishmaniasis (VL) is a neglected tropical disease caused by Leishmania parasites. VL is characterised by uncontrolled parasite replication in internal organs and is often fatal if untreated. Monocytes are part of a group of cells called white blood cells. These cells can become activated and play an important role against infections. They have been poorly characterised in VL patients. The aim of this study was to evaluate the expression levels of markers of activation on different subsets of monocytes from the blood of VL patients and healthy non-endemic controls (HNEC). We assessed the expression levels of monocyte markers that are essential for activating and regulating the immune response. Our results how that these are increased on some monocyte subsets at the time of diagnosis as compared to the end of treatment and HNEC. We also looked at a marker that can inhibit the immune response and show that it is highly expressed at the time of diagnosis as compared to the end of treatment and HNEC. These results show that monocytes from the blood of VL patients upregulate both activating and inhibitory receptors and that their expression levels are restored at the end of treatment. [ABSTRACT FROM AUTHOR]

This study investigated the mechanism of the extracellular matrix-mimicking hydrogel-mediated TGFB1/Nrf2 signaling pathway in osteoarthritis using bone marrow mesenchymal stem cell-derived exosomes (BMSCs-Exos). A GMOCS-Exos hydrogel was synthesized and evaluated for its impact on chondrocyte viability and neutrophil extracellular traps (NETs) formation. In an OA rat model, GMOCS-Exos promoted cartilage regeneration and inhibited NETs formation. Transcriptome sequencing identified TGFB1 as a key gene, with GMOCS-Exos activating Nrf2 signaling through TGFB1. Depletion of TGFB1 hindered the cartilage-protective effect of GMOCS-Exos. This study sheds light on a promising therapeutic strategy for osteoarthritis through GMOCS-Exos-mediated TGFB1/Nrf2 pathway modulation. [ABSTRACT FROM AUTHOR]