Hematopoietic Activity Research Articles

The hematopoietic activity of EPO is unfavorable to the treatment of bleomycin-induced pulmonary fibrosis in mice

The main function of erythropoietin (EPO) is to promote hematopoiesis and improve anemia. In addition, EPO also has many non-hematopoietic effects such as anti-inflammation, anti-apoptosis and anti-oxidation. To achieve the protective effects, large doses of EPO are required, so the probability of side effects increases. Previous studies have revealed that EPO can improve pulmonary fibrosis in mice, but it has not been clarified whether the hematopoiesis of EPO contributes to amelioration of pulmonary fibrosis and whether EPO improves overall mortality. Our results show that EPO decreases hydroxyproline content, α-sma and col-1 protein levels in mice with bleomycin-induced pulmonary fibrosis. However, compared with the control group, the weight loss and mortality rate of the EPO group were not improved, while the number of red blood cells (RBCs), hemoglobin (Hb), red cell width distribution-coefficient of variation (RDW-CV) and hematocrit (HCT) were significantly higher. Furthermore, we observed massive thrombosis in the lung of EPO treated lung fibrosis mice but not in control mice. Therefore, our results show that in the condition of lung fibrosis, the hematopoietic activity of exogenous EPO is not conducive to its tissue protective effect.

Behavioural Monitoring Underlines Habituation to Repeated Stressor Stimuli in Farmed Gilthead Sea Bream (Sparus aurata) Reared at a High Stocking Density.

A confinement stress test with 75% tank space reduction and behavioural monitoring through tri-axial accelerometers externally attached to the operculum was designed. This procedure was validated by demonstrating the less pronounced stress response in gilthead sea bream than in European sea bass (950-1200 g). Our study aimed to assess habituation to high stocking densities with such procedure in gilthead sea bream. Animals (420-450 g) were reared (June-August) in a flow-through system at two stocking densities (CTRL: 10-15 kg/m3; HD: 18-24 kg/m3), with natural photoperiod and temperature (21-29 °C), and oxygen levels at 5.2-4.2 (CTRL) and 4.2-3.2 ppm (HD). At the end, blood and muscle were sampled for haematology and transcriptomic analyses, and external tissue damage was assessed by image-based scoring. Four days later, fish underwent a 45 min confinement stress test over two consecutive days. HD fish showed reduced feed intake, growth rates and haematopoietic activity. Muscle transcriptome changes indicated a shift from systemic to local growth regulation and a primed muscle regeneration over protein accretion in HD animals with slight external injuries. After stress testing, HD fish exhibited a decreased recovery time in activity and respiration rates, which was shorter after a second stressor exposure, confirming habituation to high densities.

Effect of interleukin 1b inhibition with canakinumab on inflammation and viral persistence in people with human immunodeficiency virus

Abstract Introduction Effectively treated people with HIV (PWH) have elevated risk of cardiovascular disease (CVD). Inflammatory markers are predictive of CVD and mortality among PWH. The role of the myeloid system in driving inflammation and atherosclerosis has been recently recognized. Canakinumab (a monoclonal antibody to IL-1β) reduces inflammation and CVD events among people with elevated hsCRP after myocardial infarction without HIV. We evaluated the impact of IL-1β inhibition using canakinumab on HIV parameters, inflammation, HIV persistence markers, arterial inflammation, and hematopoietic activity in PWH. Methods PWH on effective ART who had CVD or were at risk for CVD were randomized 2:1 to receive 150 mg of canakinumab subcutaneously or matched placebo at weeks 0 and 12. Arterial inflammation and bone marrow metabolic activity were assessed using F18 FDG PET/CT at baseline and week 18. T cell and monocyte activation were evaluated using multiparameter spectral cytometry. The viral reservoir was quantified using Tat/rev Induced Limiting Dilution Assay (TILDA), HIV DNA and cell-associated RNA. The primary endpoints were change in CD4 and CD8 count. We assessed group effects over time using linear mixed effects models. Results 33 individuals were randomized (median age of 60 years old (IQR 57.5, 64.5) and 94% male); 25 received canakinumab and 8 received placebo. There were no significant differences at baseline. As expected, IL-1β increased among those treated with canakinumab at weeks 4- 24 (p<0.01 for each) and returned to baseline at week 36. There was one death from sepsis in an individual aged 84 with CVD and poorly controlled diabetes who received canakinumab. There were no significant changes in CD4 count, CD8 count, platelet count, creatinine, AST, or ALT by group. Treatment was not associated with a greater reduction in arterial inflammation in the most diseased segment compared to placebo (-6.9%; 95% CI -30.4 to 24.5%; p=0.62). However, bone marrow metabolic activity decreased in the canakinumab group versus placebo (-14.4%, 95% CI -26.5% to -0.2%; p=0.047). Treatment was associated with increased CD163 expression on monocytes at weeks 24 (p=0.03) and 36 (p<0.001), and lower caspase activity at week 36 (p=0.02). There was expansion of anti-inflammatory CD16+ patrolling monocytes that co-express CD163+CX3CR1+ and a decrease in pro-inflammatory CD16+ patrolling monocytes that are Caspase1+CCR2+. Treatment was not associated with differences in hsCRP, IL-6, IL-16, IL-18, MCP-1, sCD14, sCD163, T cell subsets, NK cell subsets, or viral persistence markers. Conclusion Among treated PWH, targeted inhibition of IL-1β using canakinumab results in decreased bone marrow metabolic activity and a shift toward anti-inflammatory monocyte populations. These findings shed light on mechanisms underlying how targeted IL-1β inhibition using canakinumab prevents CVD events by altering monocyte populations and reducing systemic inflammation.

An NAD+-dependent metabolic checkpoint regulates hematopoietic stem cell activation and aging.

How hematopoietic stem cells (HSCs) maintain metabolic homeostasis to support tissue repair and regeneration throughout the lifespan is elusive. Here, we show that CD38, an NAD+-dependent metabolic enzyme, promotes HSC proliferation by inducing mitochondrial Ca2+ influx and mitochondrial metabolism in young mice. Conversely, aberrant CD38 upregulation during aging is a driver of HSC deterioration in aged mice due to dysregulated NAD+ metabolism and compromised mitochondrial stress management. The mitochondrial calcium uniporter, a mediator of mitochondrial Ca2+ influx, also supports HSC proliferation in young mice yet drives HSC decline in aged mice. Pharmacological inactivation of CD38 reverses HSC aging and the pathophysiological changes of the aging hematopoietic system in aged mice. Together, our study highlights an NAD+ metabolic checkpoint that balances mitochondrial activation to support HSC proliferation and mitochondrial stress management to enhance HSC self-renewal throughout the lifespan, and links aberrant Ca2+ signaling to HSC aging.

Hematopoietic stem cell transplantation activity in China 2022-2023. The proportions of peripheral blood for stem cell source continue to grow: a report from the Chinese Blood and Marrow Transplantation Registry Group.

Over past two years, a total of 39,918 hematopoietic stem cell transplantation (HSCT) cases were reported, with 18,194 and 21,714 transplants performed in 2022 and 2023, respectively. Autologous HSCT accounted for 6562 cases (31%) in 2022, while allogeneic HSCT comprised 12,632 cases (69%). In 2023, the number of allogeneic HSCTs exceeded 15,000, maintaining a 69% share. Participation in the 2022 and 2023 surveys included 193 and 212 transplantation teams, respectively, from 27 provinces, municipalities, or autonomous regions. The leading indication of HSCT was acute leukemia, including acute myeloid leukemia (AML), acute lymphoblastic leukemia (ALL), and mixed phenotype acute leukemia, with a total of 17,421 cases. AML was the most common disease (10,339, 38%) for allogeneic HSCT, which was followed by ALL (5925 cases, 21%). Peripheral blood emerged as the primary source of stem cell grafts, utilized in 54% of matched sibling donor transplants and 77% of haploidentical donor transplants. The BuCy-based conditioning regimen was the most prevalent, used in 53% of allogeneic HSCT cases in the past two years. This survey offers a comprehensive overview of the current HSCT landscape and serves as a valuable resource for clinical practice.

Transcriptomic analysis of BM-MSCs identified EGR1 as a transcription factor to fully exploit their therapeutic potential

Bone marrow-mesenchymal stromal cells (BM-MSCs) are key components of the BM niche, where they regulate hematopoietic stem progenitor cell (HSPC) homeostasis by direct contact and secreting soluble factors. BM-MSCs also protect the BM niche from excessive inflammation by releasing anti-inflammatory factors and modulating immune cell activity. Thanks to these properties, BM-MSCs were successfully employed in pre-clinical HSPC transplantation models, increasing the rate of HSPC engraftment, accelerating the hematological reconstitution, and reducing the risk of graft failure. However, their clinical use requires extensive in vitro expansion, potentially altering their biological and functional properties. In this work, we analyzed the transcriptomic profile of human BM-MSCs sorted as CD45−, CD105+, CD73+, and CD90+ cells from the BM aspirates of heathy-donors and corresponding ex-vivo expanded BM-MSCs. We found the expression of immune and inflammatory genes downregulated upon cell culture and selected the transcription factor EGR1 to restore the MSC properties. We overexpressed EGR1 in BM-MSCs and performed in vitro tests to study the functional properties of EGR1-overexpressing BM-MSCs. We concluded that EGR1 increased the MSC response to inflammatory stimuli and immune cell control and potentiated the MSC hematopoietic supportive activity in co-culture assay, suggesting that the EGR1-based reprogramming may improve the BM-MSC clinical use.

Mononuclear Phagocytes, Cellular Immunity, and Nobel Prizes: A Historic Perspective.

The mononuclear phagocyte system includes monocytes, macrophages, some dendritic cells, and multinuclear giant cells. These cell populations display marked heterogeneity depending on their differentiation from embryonic and bone marrow hematopoietic progenitors, tissue location, and activation. They contribute to tissue homeostasis by interacting with local and systemic immune and non-immune cells through trophic, clearance, and cytocidal functions. During evolution, they contributed to the innate host defense before effector mechanisms of specific adaptive immunity emerged. Mouse macrophages appear at mid-gestation and are distributed throughout the embryo to facilitate organogenesis and clear cells undergoing programmed cell death. Yolk sac, AGM, and fetal liver-derived tissue-resident macrophages persist throughout postnatal and adult life, supplemented by bone marrow-derived blood monocytes, as required after injury and infection. Nobel awards to Elie Metchnikoff and Paul Ehrlich in 1908 drew attention to cellular phagocytic and humoral immunity, respectively. In 2011, prizes were awarded to Jules Hoffmann and Bruce Beutler for contributions to innate immunity and to Ralph Steinman for the discovery of dendritic cells and their role in antigen presentation to T lymphocytes. We trace milestones in the history of mononuclear phagocyte research from the perspective of Nobel awards bearing directly and indirectly on their role in cellular immunity.

<i>In situ</i> and <i>in silico</i> modeling of the hematopoiesis-inducing effect of chelidonic acid

The current trend in regenerative medicine, in the context of an aging population, is the search for new ways and means to optimize tissue bioengineering. One of the convenient models for in situ studying bone marrow regeneration is the subcutaneous ectopic osteogenesis test on scaffolds that imitate the architecture of bone tissue. Chelidonic acid (CA), a small molecule, is capable of participating in various cellular processes and metabolic pathways, and it can activate the osteogenic differentiation of mesenchymal stem cells. However, the molecular mechanisms behind the regulatory effects of CA remain unknown. The aim of this study was to investigate the modulatory effect of CA on the in situ formation of hematopoietic foci, as well as to predict target genes and intracellular signalling pathways involved in the hematopoietic activity of CA. An aqueous solution of CA, isolated from an extract of the Saussurea controversa plant. Course (daily for 35 days) oral administration of CA. Ectopic osteogenesis testing in Balb/c mice. Morphometric analysis of histological sections after 45 days and in silico modelling of gene expression with statistical analysis. CA, when administered orally in a low dose (10 mg/kg), threefold increases the normalized area of bone marrow in the composition of bone tissue plates grown in situ in a test of ectopic subcutaneous osteogenesis in mice. This effect is associated essentially (a probability of CA activity Pa 0.5 and a probability of inactivity Pi 0.5) with enhanced expression of 358 hematopoiesis-related genes, as predicted by in silico analysis. The top list with the highest Pa value included 10 target genes, such as GATA1, CITED2, SFRP1, EP300, LGALS9, VNN1, IL10RB, RARA, CD83, and HMOX1. CA has a significant ability to enhance the reparative remodelling of hematopoietic tissue in situ. The next phase of research will be to test actual target genes and signalling pathways that mediate the regulatory effect of HC on hematopoiesis both in vitro and in vivo, as well as in clinical settings.

Mitochondrial permeability transition dictates mitochondrial maturation upon switch in cellular identity of hematopoietic precursors

The mitochondrial permeability transition pore (mPTP) is a supramolecular channel that regulates exchange of solutes across cristae membranes, with executive roles in mitochondrial function and cell death. The contribution of the mPTP to normal physiology remains debated, although evidence implicates the mPTP in mitochondrial inner membrane remodeling in differentiating progenitor cells. Here, we demonstrate that strict control over mPTP conductance shapes metabolic machinery as cells transit toward hematopoietic identity. Cells undergoing the endothelial-to-hematopoietic transition (EHT) tightly control chief regulatory elements of the mPTP. During EHT, maturing arterial endothelium restricts mPTP activity just prior to hematopoietic commitment. After transition in cellular identity, mPTP conductance is restored. In utero treatment with NIM811, a molecule that blocks sensitization of the mPTP to opening by Cyclophilin D (CypD), amplifies oxidative phosphorylation (OXPHOS) in hematopoietic precursors and increases hematopoiesis in the embryo. Additionally, differentiating pluripotent stem cells (PSCs) acquire greater organization of mitochondrial cristae and hematopoietic activity following knockdown of the CypD gene, Ppif. Conversely, knockdown of Opa1, a GTPase critical for proper cristae architecture, induces cristae irregularity and impairs hematopoiesis. These data elucidate a mechanism that regulates mitochondrial maturation in hematopoietic precursors and underscore a role for the mPTP in the acquisition of hematopoietic fate.

Identification of Active Molecules against Thrombocytopenia through Machine Learning.

Thrombocytopenia, which is associated with thrombopoietin (TPO) deficiency, presents very limited treatment options and can lead to life-threatening complications. Discovering new therapeutic agents against thrombocytopenia has proven to be a challenging task using traditional screening approaches. Fortunately, machine learning (ML) techniques offer a rapid avenue for exploring chemical space, thereby increasing the likelihood of uncovering new drug candidates. In this study, we focused on computational modeling for drug-induced megakaryocyte differentiation and platelet production using ML methods, aiming to gain insights into the structural characteristics of hematopoietic activity. We developed 112 different classifiers by combining eight ML algorithms with 14 molecule features. The top-performing model achieved good results on both 5-fold cross-validation (with an accuracy of 81.6% and MCC value of 0.589) and external validation (with an accuracy of 83.1% and MCC value of 0.642). Additionally, by leveraging the Shapley additive explanations method, the best model provided quantitative assessments of molecular properties and structures that significantly contributed to the predictions. Furthermore, we employed an ensemble strategy to integrate predictions from multiple models and performed in silico predictions for new molecules with potential activity against thrombocytopenia, sourced from traditional Chinese medicine and the Drug Repurposing Hub. The findings of this study could offer valuable insights into the structural characteristics and computational prediction of thrombopoiesis inducers.

Persistent cytopenias after anti-BCMA CAR T-cell therapy are associated with reduced hematopoietic activity in posttreatment bone marrows.

We attempt to analyze bone marrow findings and correlation with cytopenia(s) after anti-B-cell maturation antigen (BCMA) chimeric antigen receptor (CAR) T-cell infusion in this study. Relevant clinicopathologic data, including complete blood counts, neutrophil counts, relevant therapy history, and pre- and posttherapy bone marrow evaluations, were studied in 12 patients who received anti-BCMA CAR T-cell therapy. Bone marrow findings after CAR T-cell therapy were available in 6 of 12 cases, 3 of which showed markedly hypocellular marrow with either markedly reduced or essentially absent hematopoiesis. One case showed a hypocellular marrow with trilineage hematopoiesis, while the remaining 2 cases showed persistent involvement by plasma cell myeloma. Reticulin stains did not reveal significant fibrosis. Ten patients had anemia, and 8 patients had leukopenia and thrombocytopenia at day 90 posttherapy. Long-term follow-up showed persistent disease in 10 of 12 cases. Prolonged cytopenias occur in most patients after BCMA CAR T-cell therapy with bone marrow evaluations demonstrating associated marked hypocellularity with minimal or no hematopoiesis without an increase in fibrosis.

Potential Therapeutic Implications of Securidaca longipedunculata Root Bark Ethanolic Extract in a Rat Model of Traumatic Brain Injury

This study explores the neuroprotective potential of Securidaca longipedunculata (Violet tree) used in traditional African medicine for treating traumatic brain injury (TBI). Fifteen albino rats were divided into three groups: a control group without TBI or treatment, a TBI group treated with S. longipedunculata (400 mg/kg body weight for 21 days), and a TBI group without treatment. TBI was induced using the weight drop method. Neurological responses were assessed using a revised neurological severity score, and haematological parameters (WBC, RBC, HB, PCV, neutrophils, lymphocytes, and monocytes) were measured, including the neutrophil to lymphocyte ratio. Plasma glucose levels were monitored hourly for three hours post-TBI and daily for three days. Histological analysis of brain tissues was performed. Results indicated that rats treated with S. longipedunculata exhibited significantly lower neurological severity scores and better responsiveness compared to untreated TBI rats during the first two weeks of treatment. Treated rats also showed higher PCV, HB, and RBC levels, and lower WBC, neutrophil, and lymphocyte counts. Plasma glucose levels in treated rats steadily decreased, a trend not seen in untreated TBI rats. Histology revealed less severe brain lesions in treated rats. The study concludes that S. longipedunculata may reduce inflammatory responses and enhance hematopoietic activity in TBI rats, suggesting its potential for developing new neuroprotective pharmaceuticals.

Structural analysis and blood-enriching effects comparison based on biological potency of Angelica sinensis polysaccharides.

Angelica sinensis is a long-standing medicine used by Chinese medical practitioners and well-known for its blood-tonic and blood-activating effects. Ferulic acid, ligustilide, and eugenol in Angelica sinensis activate the blood circulation; however, the material basis of their blood-tonic effects needs to be further investigated. In this study, five homogeneous Angelica sinensis polysaccharides were isolated, and their sugar content, molecular weight, monosaccharide composition, and infrared characteristics determined. Acetylphenylhydrazine (APH) and cyclophosphamide (CTX) were used as inducers to establish a blood deficiency model in mice, and organ indices, haematological and biochemical parameters were measured in mice. Results of in vivo hematopoietic activity showed that Angelica sinensis polysaccharide (APS) could elevate erythropoietin (EPO), granulocyte colony-stimulating factor (G-CSF), and interleukin-3 (IL-3) serum levels, reduce tumor necrosis factor-α (TNF-α) level in mice, and promote hematopoiesis in the body by regulating cytokine levels. Biological potency test results of the in vitro blood supplementation indicated strongest tonic activity for APS-H2O, and APS-0.4 has the weakest haemopoietic activity. The structures of APS-H2O and APS-0.4 were characterized, and the results showed that APS-H2O is an arabinogalactan glycan with a main chain consisting of α-1,3,5-Ara(f), α-1,5- Ara(f), β-1,4-Gal(p), and β-1,4-Gal(p)A, and two branched chains of β-t-Gal(p) and α-t-Glc(p) connected to each other in a (1→3) linkage to α-1,3,5-Ara(f) on the main chain. APS-0.4 is an acidic polysaccharide with galacturonic acid as the main chain, consisting of α-1,4-GalA, α-1,2-GalA, α-1,4-Gal, and β-1,4-Rha. In conclusion, APS-H2O can be used as a potential drug for blood replenishment in patients with blood deficiency, providing a basis for APS application in clinical treatment and health foods, as well as research and development of new polysaccharide-based drugs.

Adaptation to ex vivo culture reduces human hematopoietic stem cell activity independently of the cell cycle

AbstractLoss of long-term hematopoietic stem cell (LT-HSC) function ex vivo hampers the success of clinical protocols that rely on culture. However, the kinetics and mechanisms through which this occurs remain incompletely characterized. In this study, through time-resolved single-cell RNA sequencing, matched in vivo functional analysis, and the use of a reversible in vitro system of early G1 arrest, we defined the sequence of transcriptional and functional events that occur during the first ex vivo division of human LT-HSCs. We demonstrated that the sharpest loss in LT-HSC repopulation capacity happens early on, between 6 and 24 hours of culture, before LT-HSCs commit to cell cycle progression. During this time window, LT-HSCs adapt to the culture environment, limit the global variability in gene expression, and transiently upregulate gene networks involved in signaling and stress responses. From 24 hours, LT-HSC progression past early G1 contributes to the establishment of differentiation programs in culture. However, contrary to the current assumptions, we demonstrated that the loss of HSC function ex vivo is independent of cell cycle progression. Finally, we showed that targeting LT-HSC adaptation to culture by inhibiting the early activation of JAK/STAT signaling improves HSC long-term repopulating function ex vivo. Collectively, our study demonstrated that controlling early LT-HSC adaptation to ex vivo culture, for example, via JAK inhibition, is critically important to improve HSC gene therapy and expansion protocols.

Relationship between Femoral Proximal Bone Quality Assessment by MRI IDEAL-IQ Sequence and Body Mass Index in Elderly Men.

Bone assessment using the MRI DEAL-IQ sequence may have the potential to serve as a substitute for evaluating bone strength by quantifying the bone marrow hematopoietic region (R2*) and marrow adiposity (proton density fat fraction: PDFF). Higher body mass index (BMI) is associated with increased bone mineral density (BMD) in the proximal femur; however, the relationship between BMI and R2* or PDFF remains unclear. Herein, we investigated the correlation between BMI and MRI IDEAL-IQ based R2* or PDFF of the proximal femur. A retrospective single-cohort study was conducted on 217 patients diagnosed with non-metastatic prostate cancer between September 2019 and December 2022 who underwent MRI. The correlation between BMI and R2* or PDFF of the proximal femur was analyzed using Spearman's rank correlation test. Among 217 patients (median age, 74 years; median BMI, 23.8 kg/m2), there was a significant positive correlation between BMI and R2* at the right and left proximal femur (r = 0.2686, p < 0.0001; r = 0.2755, p < 0.0001, respectively). Furthermore, BMI and PDFF showed a significant negative correlation (r = -0.239, p = 0.0004; r = -0.2212, p = 0.001, respectively). In elderly men, the increased loading on the proximal femur due to elevated BMI was observed to promote a decrease in bone marrow adiposity in the proximal femur, causing a tendency for a transition from fatty marrow to red marrow with hematopoietic activity. These results indicate that the MRI IDEAL-IQ sequence may be valuable for assessing bone quality deterioration in the proximal femur.

Histopathology and micronuclei induction as pollution biomarkers in common carp, Cyprinus carpio from southern Iraq

This study aimed to assess the histopathological alterations and micronuclei induction in the gill, kidney and liver of common carp, Cyprinus carpio from Al-Huwaizah Marshes, Al-Hammar Marshes and Al-Sweap River. Thirty C. carpio were sampled at each locality using monofilament gillnets. Most prominent histopathological alterations recorded in the gill included formation venous sinus in primary lamellae, oedema, curling and distortion of primary lamellae fusion of secondary lamellae, hyperplasia of epithelial cells, necrosis, curling of secondary lamellae, severe dilation of lamellar capillaries, clavate lamellae formation at the tip of secondary lamellae, a proliferation of cartilage tissue in primary lamellae and lifting of the lamellar epithelium whereas congestion, fibrosis with proliferative inflammation, necrosis area, degenerated cells, vacuolar degeneration, vacuolation, nuclear pyknosis, hypertrophy of hepatocytes were reported in the liver. In the kidney, the most pronounced changes were necrosis of the hematopoietic tissue, hyaline droplet and activation of melanomacrophage centres. A higher prevalence of alterations was observed in the population from Al-Huwaizah Marshes, however, Al-Hammar population exhibited severe pathologies. Micronuclei frequency was significantly higher at Al-Huwaizah Marsh (p &lt; 0.05) with low frequency being recorded at Al-Sweap River. This study attests to the effectiveness of histopathology and micronucleus induction as potential tools for discriminating the health of populations from different water bodies.

Abstract 4177: High-throughput in vivo monitoring of splenomegaly and tumor burden in a murine breast cancer model

Abstract Splenomegaly is a valuable parameter in mouse model cancer studies, as it can reflect the magnitude of cancer burden, hematopoietic activity, immune status, and can provide an indirect measure of cancer treatment efficacy. In liquid cancer models specifically (leukemia/lymphoma), spleen sizing is important as it is usually the only measure of in vivo tumor burden that can be assessed noninvasively without genetic labeling of tumor cells. Magnetic resonance imaging (MRI) and contrast-enhanced computed tomography (CT) are highly effective at evaluating spleen size in small animals. However, these techniques can impose limitations on large-cohort study designs due to high cost, long scan time, and ionizing radiation. Ultrasound is an alternative method with lower cost, high frame rate, and no ionization, but can suffer from poor inter-user variability, limited 2D field-of-view, and low throughput due to manual operation. In this work, we evaluated a novel 3D automated ultrasound scanner (Vega, Revvity, Inc.) for rapid assessment of splenomegaly in a murine cancer model. Female BALB/c mice (n=10) were implanted with 5e5 4T1 (ATCC) cells on the right flank. Mice were imaged at five timepoints over 25 days to track longitudinal progression of both spleen and tumor enlargement. Images were segmented manually in 3D using the “Slice Draw” and “Fill Between Slices” effects in SonoEQ v2.0.1 (Revvity, Inc.) to quantify tissue volume. After the final timepoint, mice were euthanized, and spleen weight was measured ex vivo. An additional cohort of age-matched mice without tumors (n=7) were imaged at the final timepoint to serve as controls. Imaging revealed a substantial enlargement of the spleen over time, from 30 ± 3 mm3 to 545 ± 105 mm3, representing an 18-fold increase. In the same time span, tumor volume grew to 1966 ± 87 mm3. Correlation analysis demonstrated good agreement between ultrasound volumes and ex vivo spleen weights (R² = 0.90). The results in this study demonstrate that noninvasive, nonlabelled quantification of murine spleen size with automated ultrasound is feasible, robust, and fast. The average time to acquire the spleen image for each mouse was less than 30 seconds. Future studies will apply this workflow in liquid cancer models, as well as explore using machine learning approaches to automatically segment spleen borders for faster data analysis. Citation Format: Craig McMannus, Tomek J. Czernuszewicz, Ryan C. Gessner, Jeffrey D. Peterson. High-throughput in vivo monitoring of splenomegaly and tumor burden in a murine breast cancer model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4177.

Abstract P382: Epigenetic Regulation of the NF-kB Pathway by the Neural-Hematopoietic-Inflammatory Axis as a Potential Link Between Psychosocial Stress and Cardiovascular Risk: Data From the Washington DC Cardiovascular Health and Needs Assessment

Introduction: Chronic psychosocial stress (cPSS) is associated with cardiovascular disease (CVD) risk, caused in part by dysregulation of the neural-hematopoietic-inflammatory axis and epigenetic changes. cPSS may also affect NF-kB dependent pathways, suggesting a potential link to accelerated CVD risk and health inequities for populations most impacted by adverse social determinants. Hypothesis: We propose cPSS associates with greater amygdala activity (AmygA), a stress marker, and splenic activity (SpleenA), a hematopoietic activation measure. This relates to higher pro-inflammatory cytokine levels, partially due to less DNA methylation of NF-kB pathway-related genes. Methods: 60 African American adults (93.3% female, mean age 61) with CVD risk, living in the Washington, D.C. area underwent 18 FDG PET/CT to evaluate AmygA and SpleenA. DNA methylation analysis assessed epigenetic associations of the NF- κ B1/2 gene in PBMCs and ELISA- measured serum IL-1β and TNFα. Multivariable regression analysis adjusted for atherosclerotic CVD 10-year risk score and BMI was used to examine associations. Results: Greater AmygA and SpleenA were significantly associated with one another (β=0.26; p=0.003) and both were associated with greater pro-inflammatory cytokines IL1-β (AmygA:β =0.36, SpleenA:β=0.72, p&lt;0.05) and TNF-α (AmygA:β=0.31, SpleenA:β=0.58, p&lt;0.05). Further, we identified 2 significant methylation sites out of 81 on the NF- κ B1/2 gene. Notably, AmygA and SpleenA were inversely associated with the NF-κB1 cg01983105 and cg07955720 methylation sites (Table). Conclusions: We highlight a possible link between AmygA and SpleenA with decreased DNA methylation of the NF- κB gene. Our findings demonstrate a potential relationship between chronic stress-related neural activity and CVD risk through immune function and epigenetic alterations. These results should be examined in larger, diverse population-based cohorts with longitudinal data to identify intervention targets for reducing health inequities.

Hematopoietic cell transplantation and cell therapy activity landscape survey in the Kingdom of Saudi Arabia; a report from the Saudi Society of Blood and Marrow Transplantation (SSBMT)

Hematopoietic Cell Transplantation (HCT) activity was surveyed in the Kingdom of Saudi Arabia (KSA). The overall rate of HCT per 10,000,000 inhabitants doubled every 10 years. 15,031 HCTs were reported by all the functional HCT centers in KSA since inception of HCT program. Out of total HCT 15,031; 10,232(68%) were reported in adults, and 4799(32%) in the pediatric population. Allogeneic HCT constituted 10,489(70%) of total HCT, with majority from Human Leukocyte Antigen matched identical sibling (85.4%). The autologous HCTs were 4542(30%). During the last five years 2018–2022; in total 5164 HCTs were performed, with the majority had allogeneic HCT 3,085(59.74%), followed by the autologous HCT 3085(40.2%). The top three main indications of the autologous HCT were Multiple Myeloma 299(28%), Hodgkin Lymphoma 293(27.8%), and Non-Hodgkin Lymphoma 212(20%). Hemoglobinopathies 615(27.6%) were mostly indicated for allogeneic HCT, followed by Acute Myeloid Leukemia 433(19.4%), and Precursors Lymphoid Neoplasms 322(14.4%). The HCT activity landscape survey provides the updated current state and trends for HCT in KSA. The reported HCT numbers differ than what was reported by international registries, since not all the cases have been reported. We urge to have a common data hub nationally in order to capture the actual number of cases.

Isolation of Murine Neonatal and Adult Osteomacs to Examine Their Role in the Hematopoietic Niche.

Maintenance of hematopoietic stem cell (HSC) function is an orchestrated event between multiple cell types, and crosstalk between these cell types is an essential part of HSC regulation. Among the cell groups of the niche involved in this process are a group of bone-resident macrophages known as osteomacs (OM). Previously, it was demonstrated that OM and osteoblasts contained within neonatal calvarial cells are critical to maintain hematopoietic function. Additionally, interactions between neonatal calvarial cells and megakaryocytes further enhance this hematopoietic activity. In this chapter, we explore one such interaction involving OM and osteoblasts in the hematopoietic niche. We describe a protocol to isolate OM from both neonatal and adult mice, and subsequently use colony-forming assays to demonstrate their interaction with osteoblasts in maintaining HSC function.