Bone Marrow Status Research Articles

Can peripheral blood provide good DNA methylation biomarkers in myelodysplastic syndrome?

Myelodysplastic syndromes (MDS) are a group of hematological stem cell malignancies strongly associated with aberrant epigenetic anomalies, namely DNA methylation. Blood-based specimens may be a potential source of noninvasive DNA methylation cancer biomarkers. Systemic methylation profile has been explored in solid tumors but is still largely unknown in hematological cancers. We compared DNA methylation status in bone marrow (BM) aspirates and peripheral blood (PB) in MDS patients at diagnosis. Using MS-PCR, we compared DNA methylation status of nine tumor suppressor genes (TSG) P15, P16, TP53, DAPK, MGMT, and TRAIL receptors (TRAIL-DcR1, -DcR2, -DR4, and -DR5) genes. Statistical analysis was performed using the chi-square test, and Kappa statistics analyzed the concordance between BM and PB methylation. Overall survival was assessed by the Kaplan-Meier method. In MDS patients, we observed a high methylation status of the analyzed genes, mainly P15 (64.7%) and DAPK (60.3%). Moreover, 75% of MDS patients presented more than two hypermethylated genes, and these patients had a significantly lower overall survival. We observed a good correlation between gene methylation patterns in PB and BM samples, mainly for P15 (70.6% concordance; kappa = 0.344) and TRAIL-DcR1 (75% concordance; kappa = 0.243). No patient presented TP53 and MGMT methylated genes. Our results suggest that DNA methylation patterns measured in PB may have great potential as informative biomarkers of MDS-related tumor suppressor genes methylation.

Study on Relationships of Tumor Status and Gene Polymorphism With Blood Concentration of MTX and Toxicities in 63 Pediatric Mature B Cell Lymphoma in Chinese Population

Objective:This study investigated the relationships of tumor status (stage, renal involvement, bone marrow status, bulky disease, liver function), tumor gene polymorphism, and methotrexate (MTX) dosage (stratified by treatment group) with blood MTX levels and adverse reactions (ADR).Methods:We retrospectively reviewed 63 mature B cell lymphoma patients who were treated in our center. Genotyping of the MTHFR 677 and SLCO1B1 genes was carried out, and the relationships between tumor status, polymorphism of the genes, MTX level, and ADR were analyzed.Results:Altogether, 63 children were included. The mean blood MTX concentration was 0.25 ± 0.2 umol/L at 45 h. Liver dysfunction and bulky disease were both correlated with MTX level (both P < 0.05). ADRs were higher among patients with blood MTX > 0.5 mmol/l at 45 h than for the groups with lower blood MTX. The MTHFR 677 CT genotype was correlated with liver function damage (P = 0.04); the rs11045879 locus CC genotype of SLCO1B1, stage IV, and bulky disease at the time of diagnosis were correlated with 4° neutropenia (P < 0.05). Stage IV, bulky disease, leukemia stage at the time of diagnosis, and C2 treatment group were correlated with severe anemia (P < 0.05). Stage IV, bulky disease, leukemia stage, renal invasion at the time of diagnosis, and C2 treatment group were associated with severe thrombocytopenia (P < 0.05). Bulky disease and renal invasion at the time of diagnosis were associated with severe mucositis and severe infection (P < 0.05).Conclusion:Taken together, our data demonstrate that gene polymorphism, MTX levels, tumor status, and treatment group might be useful to optimize MTX therapy and estimate toxicity.

Abraxane-induced bone marrow CD11b+ myeloid cell depletion in tumor-bearing mice is visualized by μPET-CT with 64Cu-labeled anti-CD11b and prevented by anti-CSF-1.

To investigate the utility of noninvasive µPET-CT with 64Cu-DOTA-anti-CD11b (64Cu-αCD11b) in assessing bone marrow status after anticancer therapies, and the protective role of anti-CSF-1 (αCSF-1) against bone marrow suppression induced by Abraxane.Methods: MDA-MB-435 tumor-bearing mice were treated with Abraxane, αCSF-1, or αCSF-1 plus Abraxane. µPET-CT and biodistribution of 64Cu-αCD11b were performed after intravenous injection of the radiotracer. Cells from mouse bone marrow and MDA-MB-435 tumor were analyzed by flow cytometry. A humanized αCSF-1 was investigated for its role in protecting bone marrow cells, using a transgenic mouse model that expresses functional human CSF-1.Results: μPET-CT showed that 64Cu-αCD11b had high uptake in the bone marrow and spleen of both normal and tumor-bearing mice. Abraxane significantly reduced 64Cu-αCD11b uptake in the bone marrow and spleen of treated mice compared to untreated mice. Interestingly, 64Cu-αCD11b μPET-CT revealed that αCSF-1 alleviated the depletion of bone marrow cells by Abraxane. These changes in the bone marrow population of CD11b+ myeloid cells were confirmed by flow cytometry. Moreover, αCSF-1 potently enhanced tolerance of bone marrow granulocytic myeloid cells to Abraxane, decreased cell migration, and suppressed recruitment of myeloid cells to the tumor microenvironment. The humanized αCSF-1 also alleviated the effects of Abraxane on bone marrow cells in transgenic mice expressing human CSF-1, suggesting clinical relevance of αCSF-1 in prevention of bone marrow suppression in addition to its role in reducing tumor-infiltrating myeloid cells.Conclusions: Abraxane-induced bone marrow CD11b+ myeloid cell depletion in tumor-bearing mice could be noninvasively assessed by μPET-CT with 64Cu-αCD11b and prevented by αCSF-1.

Regulatory Role of Nano-Curcumin against Tartrazine-Induced Oxidative Stress, Apoptosis-Related Genes Expression, and Genotoxicity in Rats.

The present study evaluates the regulatory effect of Nano-Curcumin (Nano-CUR) against tartrazine (TZ)-induced injuries on apoptosis-related gene expression (i.e., p53, CASP-3 and CASP-9), antioxidant status, and DNA damages in bone marrow in treated rats. Male rats were arbitrarily separated into five groups, and each group was comprised of 10 rats each. The 1st group served as control (G1). The 2nd group ingested 7.5 mg TZ/kg. b.w. (body weight). The 3rd group ingested Nano-CUR 1 g/kg b.w. The 4th and 5th groups were respectively administered with (1 g Nano-CUR + 7.5 mg TZ/kg. b.w.) and (2 g Nano-CUR + 7.5 mg TZ/kg. b.w.). At the end of the experiment, blood samples, livers, and kidneys were collected. Livers and kidneys were homogenized and used for the analysis of reduced glutathione, malonaldhyde, total antioxidant capacity, lipid peroxide antioxidant enzyme activities, apoptosis-related gene expression, and genotoxicity by comit test. The ingestion of TZ for 50 days resulted in significant decreases in body, and kidney weights in rats and a relative increase in the liver weight compared to control. In contrast, the ingestion of Nano-CUR with TZ remarkably upgraded the body weight and relative liver weight compared to the normal range in the control. Aditionally, TZ ingestion in rats increased the oxidative stress biomarkers lipid peroxide (LPO) and malonaldehyde (MDA) significantly, whereas it decreased the reduced glutathione (GSH) levels and total antioxidant capacity (TAC). Similarly, the levels of glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CAT) significantly deteriorated in response to TZ ingestion. Moreover, the results revealed a remarkable up-regulation in the level of expression for the three examined genes, including p53, CASP-3, and CASP-9 in TZ-ingested rats compared to the control. On the other hand, the comet assay result indicates that the ingestion of TZ induced DNA damage in bone marrow. Notably, the administration of Nano-CUR protected the kidney and liver of TZ-ingested rats as evidenced by a significant elevation in all antioxidant activities of tested enzymes (i.e, SOD, GPx, and CAT), vital recovery in GSH and TAC levels, and a statistical decrease in LPO and MDA compared to TZ-ingested rats. Interestingly, the ingestion of rats with TZ modulates the observed up-regulation in the level of expression for the chosen genes, indicating the interfering role in the signaling transduction process of TZ-mediated poisoning. The results indicate that the administration of Nano-CUR may protect against TZ-induced DNA damage in bone marrow. According to the results, Nano-CUR exerted a potential protective effect against oxidative stress, DNA damage, and the up-regulation of apoptosis-related genes induced by TZ ingested to rats.

A Systematic Review of Daratumumab Based Four Drug Regimen for Newly Diagnosed Multiple Myeloma in Phase III Clinical Trials

Introduction: Daratumumab (Dara) is a human an IgG1k monoclonal antibody that targets the CD38 which is overexpressed in the malignant cells of multiple myeloma (MM). Its use has been approved for use as a single agent as well as in combination therapy for the treatment of both newly diagnosed MM (NDMM) and relapsed/refractory MM (RRMM). This review highlights the efficacy and safety of Dara in the four-drug regimen in NDMM patients (pts). Methods: We conducted a literature search using four databases (PubMed, Embase, Cochrane, and Clinicaltrials.gov). Our search strategy included Medical Subject Headings (MeSH terms) and keywords for multiple myeloma and daratumumab including trade names and generic names from the date of inception to June 2020. After excluding review articles, duplicates, and non-relevant articles, we included three phase III trials out of 588 articles reporting Dara addition to the standard of care four drug regimens for NDMM pts. Results: A total of 1998 patients were enrolled and evaluated in three-phase III randomized controlled trials. A total of 997 patients were evaluated in the Dara group and 1001 patients were evaluated in the control group. Total 1292 were transplant eligible and 706 patients were transplant ineligible. Transplant eligible Moreau et al. (2019) studied the efficacy of Dara + bortezomib (V) + thalidomide (T) + dexamethasone (d) vs VTd in newly diagnosed MM (NDMM) pts (n=1085) in CASSIOPEIA phase III trial. Addition of Dara to VTd group showed marked improvement in progression-free survival (PFS): 93% vs 85% at 18 months (hazard ratio (HR) 0.42 [0.34-0.51]; p&amp;lt;0.0001), and overall response rate (ORR) of 92.6% in Dara + VTd group as compared to 89.9% in VTd group (CI: 95%, P&amp;lt;0.0001). Minimal residual disease (MRD) negative status (10-⁵ sensitivity threshold, assessed by multiparametric flow cytometry) in bone marrow was 64% in Dara using VTd vs 44% in the VTd group (P&amp;lt;0.0001). Vorhees et al. (2020) reported addition of Dara to lenolidamide (R), and Vd in GRIFFIN study in NDMM patients (n= 207). Addition of Dara to VRd resulted in improved PFS: 95.8% ((95% CI, 89.2- 98.4) vs 89.8% ((95% CI, 77.1-95.7) at 24 months), and ORR of 99% (Odd's ratio (OR) 8.75 with 95% CI: 1.08-71.01; p=0.0160) in Dara + VRd group vs VRd group (91.8%). MRD status in bone marrow was also higher in Dara group as compared to control group (51% vs 20.4%) (p&amp;lt;0.0001). Transplant ineligible Mateos et al. (2018) reported the role of Dara + V + melphalan (M) + prednisone (P) vs VMP in NDMM pts (n=706) in a phase III trial (Alcyone). Addition of Dara to VMP group showed marked improvement in PFS: 63% vs 36 at 24 months (HR: 0.47, 95% CI 0.33-0.67, p&amp;lt;0.0001), and ORR: 90.9% vs 73.9%, respectively. MRD negative status in bone marrow was observed higher with Dara compared to without Dara using VMP (28% vs 7%) (p&amp;lt;0.0001). Significant toxicities in phase III trials mainly included pancytopenias and opportunistic infections (Table 2). Conclusion: NDMM treatment with Dara in four-drug regimens (VTd, VMP, VRd) has shown promising outcomes with improved efficacy and higher negative MRD status, providing a benchmark for future studies. Disclosures Anwer: Incyte, Seattle Genetics, Acetylon Pharmaceuticals, AbbVie Pharma, Astellas Pharma, Celegene, Millennium Pharmaceuticals.: Honoraria, Research Funding, Speakers Bureau.

A Systematic Review of Phase III Clinical Trials of Daratumumab Addition to Standard Care Regimen for Newly Diagnosed Multiple Myeloma

Introduction: In multiple myeloma (MM), plasma cells including malignant cells show expression of CD38, which is the target for daratumumab (Dara), an IgG1k monoclonal antibody, approved for MM treatment. This review highlights the efficacy and safety of Dara addition to the standard of care therapy in newly diagnosed MM (NDMM) patients (pts). Methods: We conducted a literature search using four databases (PubMed, Embase, Web of Science, and Clinicaltrials.gov). Our search strategy included MeSH terms and key words for multiple myeloma and Dara including trade names and generic names from date of inception to April 2020. A total of 587 articles were screened, and after excluding review articles, duplicates, and non-relevant articles, we included three phase III trials reporting daratumumab addition to the standard of care regimens for NDMM patients. Results: A total of 2528 patients were enrolled and evaluated in three phase III randomized controlled trials. A total of 1261 patients were in the daratumumab group and 1267 patients were in the control group. Total 1085 were transplant eligible and 1443 patients were transplant ineligible. Transplant eligible: Moreau et al. (2019) underlined the efficacy of Dara + bortezomib (V) + thalidomide (T) + dexamethasone (d) in NDMM pts (n=1085) in CASSIOPEIA phase III trial. Addition of Dara to VTd group showed marked improvent in progression free survival (PFS): 93% vs 85% at 18 months (hazard ratio (HR) 0.42 [0.34-0.51]; p&amp;lt;0.0001), and overall response rate (ORR) of 92.6% (CI: 95%, P &amp;lt;0.0001) in Dara + VTd group as compared to VTd group (89.9%). Minimal residual disease (MRD) negative status (10-⁵ sensitivity threshold, assessed by multipara metric flow cytometry) in bone marrow was 64% (P&amp;lt;0.0001) in Dara using VTd vs 44% in VTd group. Transplant ineligible: Bahlis N et al. (2019) studied Dara + lenolidamide (R) and dexamethasone (d) in NDMM pts (n=737) in MAIA phase III trial. Mateos et al. (2018) reported the role of Dara + V + melphalan (M) + prednisone (P) vs VMP in NDMM pts (n=706) in a phase III trial (Alcyone). Addition of Dara to Rd, and VMP group showed marked improvent in PFS: 68% vs 46% at 36 months [confidence interval [CI], 0.44-0.71; P&amp;lt;0.0001], and 63% vs 36 at 24 months (HR: 0.47, 95% CI 0.33-0.67, p&amp;lt;0.0001), and ORR: 93% vs 82% (P&amp;lt;0.0001), and 90.9% vs 73.9%, respectively. MRD negative status in bone marrow was observed higher with Dara compared to without Dara using Rd (24.2% vs 7.3%) (P&amp;lt;0.001), and Dara + VMP group (28% vs 7%) (p&amp;lt;0.0001) respectively. Significant toxicities mainly included pancytopenias and opportunistic infections (table 2). Standard care regimen (VTd, VMP, Rd) with Dara addition achieved superior outcomes in terms of ORR and PFS. Addition of Dara improved MRD negative status. Conclusion: NDMM treatment with Dara plus standard care therapy (VTd, VMP, Rd) has shown promising outcomes and has set a benchmark for future studies. Disclosures Anwer: Incyte, Seattle Genetics, Acetylon Pharmaceuticals, AbbVie Pharma, Astellas Pharma, Celegene, Millennium Pharmaceuticals.: Honoraria, Research Funding, Speakers Bureau.

Efficacy of Four Drug Regimens in Multiple Myeloma: A Systemic Review

Introduction: Multiple myeloma (MM) is a plasma cell dyscrasia characterized by neoplastic proliferation of plasma cells. Despite advances in treatment, therapeutic uncertainties persist. The addition of a fourth drug with the standard regimen gives a favorable prognosis and efficacy profile in MM. This systematic review highlights four-drug regimens' efficacy and safety for the treatment of newly diagnosed (ND) and relapsed refractory (RR) MM. Methodology: We performed a comprehensive literature search using four major databases (Pubmed, Cochrane Library, Embase, and ClinicalTrials.gov). Our search strategy included MeSH terms and keywords for multiple myeloma and antineoplastic agents from the date of inception to June 2020. The initial search revealed 6104 articles. After excluding review articles, duplicates, and non-relevant articles, we included 10 phase II/III clinical trials reporting the efficacy of four-drug regimens for treatment of MM. Results: Out of 2464 enrolled patients, 2321 patients had NDMM, and 143 patients had RRMM, 1791 patients were in phase III trials, and 673 patients were in phase II trials. Phase III trials: Moreau et al. (2019) studied the efficacy of daratumumab (D), bortezomib (V), thalidomide (T) and dexamethasone (d) vs VTd in NDMM patients (pts) (n=1085) in CASSIOPEIA trial. DVTd group showed better progression free survival (PFS) 93% vs 85% at 18 months (mo) (hazard ratio (HR) 0.42 [0.34-0.51]; p&amp;lt;0.0001), and an overall response rate (ORR) of 92.6% vs 89.9% compared to VTd group. Minimal residual disease (MRD) negative status in bone marrow was 64% in DVTd vs 44% in VTd group (P &amp;lt;0.0001). Mateos et al. (2018) reported the role of DV + melphalan (M) + prednisone (P) vs VMP in NDMM pts (n=706) (ALCYONE trial). DVMP group showed better PFS: 63% vs 36% at 24 mo (HR: 0.47, 95% CI 0.33-0.67, p&amp;lt;0.0001), ORR: 90.9% vs 73.9%, and MRD negative status of 28% vs 7% (p&amp;lt;0.0001) in DVMP vs VMP group. Vorhees et al. reported DVd + lenolidamide (R) vs RVd in GRIFFIN study in transplant eligible NDMM patients (n= 207). It showed better PFS: 95.8% (95% CI, 89.2- 98.4) vs 89.8% (95% CI, 77.1-95.7) at 24 mo, an ORR of 99% [Odd's ratio (OR) in DVRd group vs VRd group (91.8%) (p=0.0160) and MRD negative status of (51% vs 20.4%) (p&amp;lt;0.0001) in DVRd vs VRd group. Phase II trials: Yimer et al. (2017) studied the role of DVd + cyclophosphamide (C) in pts with NDMM (n=86) and RRMM (n=14) with ORR of 81.4% (95% CI, 71.6-89.0%) and 71.4% (95% CI, 41.9-91.6%) respectively for NDMM and RRMM. The 12-month PFS rate was 87.0% (95% CI, 57.1-96.6%), and 12-month OS rate was 98.8% (95% CI, 92.0-99.8%) for NDMM pts. Median PFS was 13.3 (95% CI, 6.8-13.3) mo and 12-month PFS rate was 66.2% (95% CI, 32.4-86.0%) and OS of 54.5% (95% CI, 8.6-86.1%) in RRMM. respectively. San et al. (2014) studied siltuximab (S) +VMP vs. VMP in NDMM pts (n=98) with ORR of 88% (95% CI 75%, 95%) in SVMP and 80% (95% CI 66%, 90%) in VMP and PFS of 88% in both arms; though median survival and overall survival were not reached in either arm despite a median follow-up of 23.3 months &amp; 21.9 mo respectively. Laubach et al. (2017) studied the role of elotuzumab (E) + Lenalidomide (R) + VP in NDMM pts (n=41 with ORR of 100%). Mikhael et al. (2015) studied the role of Carfilzomib (K) + CTd in NDMM pts (n=64) with ORR of 91% and median PFS of 85% [95% CI (71-93%)] and 76% [95% CI (59-87%)] at 12 mo and 24 mo and OS of 96% [95% CI (86-99%)] in NDMM pts. Bahlis et al. (2019) studied the role of venetoclax (VEN) + DVd vs. VEN-Dd (n=48) with RRMM pts with ORR of 92% and 88% in Ven-Dd and Ven-DVd group. Popat et al. (2016) studied the role of Panobinostat + VTd in RRMM pts (n=56) with of ORR of 91% (80% CI 83.4-96.2) and PFS of 75.4% after a median follow-up of 15 mo. Waldschmidt et al. (2018) studied the role of vorinostat + doxorubicin + Vd in RRMM pts (n=38) with PFS of 9.6 mo, and an ORR of 67%. With a median follow-up of 30.8 mo, OS was 33.8 mo with no safety concerns. Toxicities were hematological (cytopenias) and non-hematological (fatigue, infections) and generally mild (Table). Conclusion:Four drug combinations, primarily daratumumab based regimens, are very effective and well-tolerated. The achievement of higher MRD negative status implies a more profound response. Long term follow-up is needed to see the effect on long-term survival. Table Disclosures Anwer: Incyte, Seattle Genetics, Acetylon Pharmaceuticals, AbbVie Pharma, Astellas Pharma, Celegene, Millennium Pharmaceuticals.: Honoraria, Research Funding, Speakers Bureau.

A Monocentric Clinical Observation of Haploidientical Transplantation in 27 Patients with Acute Megakaryocytic Leukemia

Background Acute Megakaryocytic Leukemia (AMKL) accounts for approximately 10% of childhood AML and 1% of adult AML cases. Although AMKL with Down syndrome has a good prognosis, the prognosis for non-DS-AMKL is quite poor with a 3-years survival rate of less than 40%. At present, only allogeneic HSCT is curative. In our study, we followed 27 patients with AMKL who received a modified Bu/Cy/Mel protocol and underwent hematopoietic stem cell transplantation. The patients were then followed up with monocentric clinical observation. Methods From August 2015 to July 2020, 27 AMKL patients (14 males, 13 females, all non-Down-AMKL) with a median age of 2 years (range: 1-9 years) were continuously treated in our hospital (Hebei Yanda Lu Daopei Hospital) including 18 cases of chromosome abnormality including 3 cases of CBFA2T3/GLIS2 gene fusion (11.1%). Gene mutation included WT1(8), EVI1(5), JAK2(5): 18.51%, TET2(4), ASXL1(4), PTPN11(4): 14.81%, GATA1(2), GATA2(2): 7.4%. Bone marrow status before transplantation: 19 complete remission (CR) cases, 3 partial response (PR) cases, and 5 no response (NR) cases. There were 24 haploidentical transplants (including one patient going through 3 transplants), one transplant from a HLA-identical sibling donor and two from matched unrelated donors. Source of donor stem cells: parents in 23 cases, brothers in 2 cases, non-blood relationship in 2 cases, and none from offspring. HLA matching between the donor and recipient: 21 cases with HLA 5/10, 6 cases with ≥HLA 6/10. Haplo stem cells all came from BM+PBSC, with a median MNC input of 20.32x108/kg (10.1-26.7), CD34+ 11.68106/kg (4.05-22.44), and CD3+ 4.66x108/kg (2.11-11.29). Pre-treatment protocol: 27 patients received a modified Bu/Cy/Mel and were treated with graft-versus-host disease (GVHD) to prevent CsA+MMF+sMTX. Results During a median follow-up period of 10 months (range: 2-48 months), the 27 patients remained alive, with a median of +13 days (range: 9-21 days) to leukocyte transplantation and a median of +9 days (range: 4-38 days) to platelet transplantation. One month following transplantation, the bone marrow of all patients was 100% donor type. The overall survival (OS) rate was 63.0%, event-free survival (EFS) was 59.3%. OS was 84.2%, 33.3%, and 0% in the CR, PR, and NR groups, respectively (P&amp;lt;0.001). There were 7 cases of relapse and 10 deaths, among which 4 were caused by GVHD and 5 due to relapse. Incidence of acute GVHD (aGVHD) was 59.25% Grade I-IV and 18.51% Grade III-IV. Incidence of chronic GVHD (cGVHD) was 56%, with cystitis accounting for 14.81% of cases, 29.62% cytomegalovirus (CMV), 3.7% EBV, 0% thrombotic microangiopathy (TMA) and 18.51% infection. Conclusion For high-risk AMKL patients with poor long-term prognosis, the application of a modified Bu/Cy/Mel pretreatment significantly improves the efficacy of haploid transplantation without increasing pretreat-related death. For non-Down syndrome AMKL, we conclude that it is feasible to perform hematopoietic stem cell transplantation in CR status patients. Additional studies and multicenter and large-scale clinical studies with long-term follow-up are still needed to confirm these results. Disclosures No relevant conflicts of interest to declare.

Bone Marrow Multiparametric Magnetic Resonance Imaging with Texture Analysis for Follow-up of Advanced Stage Myelofibrosis after Transplantation

Introduction Hematopoietic cell transplantation (HCT) is a potentially curative treatment in myelofibrosis (MF). Nevertheless, in at least one-third of patients, a reliable parameter for disease response is lacking due to the absence of a molecular marker (in triple-negative MF) or the suboptimal sensitivity for CALR and MPL monitoring with routinely used PCR methods. Trephine biopsy provides a limited histological description, as it does not represent the fibrosis and/or blast eradication status of the entire bone marrow. The aim of this study is to identify magnetic resonance imaging (MRI) biomarkers that reflect response to transplant and may serve as predictors of transplant efficacy. Methods We report the case of a 45-year-old man diagnosed with triple-negative MF who was eligible for HCT following progression after a previous procedure. A pre-transplant trephine biopsy showed grade III fibrosis, according to the WHO 2016 classification. CD34+ cells were found to comprise 10%-15% of cells. He underwent MRI 8 days before bone marrow transplantation from a haploidentical donor. A second, comparative MRI was performed 6 months after HCT; concurrent chimerism was estimated through Short Tandem Repeats (STRs) analysis. A multiparametric protocol was applied, including intravoxel incoherent motion (IVIM) diffusion-weighted imaging, Dixon GRE with fat fraction calculation, and Turbo Spin Echo T1 and STIR sequences. MRI examination was performed on a 3 Tesla MRI machine and included lumbar segments L4 and L5, pelvis, sacral bone, and coccyx. A phased-array surface coil was applied to optimize signal-to-noise ratio. Finally, radiomics and texture analysis were performed on ADC sequences using specific image software post-analysis (Slicer 3D v.4.10.2). Results The selected MRI parameters showed substantial modifications between the first and second exams. T1 and STIR sequences demonstrated a decrease in bone marrow fibrosis (Figure 1). ADC values increased at pre-specified target points (iliac crest, pre-transplant: 0.762, post-transplant: 0.901; femur, pre-transplant: 0.77, post-transplant: 0.808). Moreover, among 300 features analyzed (Figure 2), 20 presented changes potentially related with bone marrow restoration. Concomitant STRs analysis showed a full donor chimerism status. Conclusions To the best of our knowledge, this is the first case of functional, textural analysis-based MRI employed in transplanted MF. Multiparametric MRI data, including anatomical and functional sequences (particularly IVIM with texture analysis of ADC values and Dixon with fat fraction calculation) may represent valuable biomarkers for accurate detection of bone marrow engraftment and chimerism. Disclosures No relevant conflicts of interest to declare.

Systematic Review of Phase III Trials of Daratumumab Based Regimens in Relapsed Refractory Multiple Myeloma

Introduction: Multiple myeloma (MM) is a hematologic malignancy in which clonal plasma cell proliferation leads to complications and death. Daratumumab (Dara) is a humanized IgGk monoclonal antibody that targets CD38- a glycoprotein expressed on plasma cells and malignant cells. Dara has direct anti-tumor effects along with immunomodulatory activities, resulting in clonal expansion of cytotoxic T cells and diminution of immunosuppressive cells. This review highlights the efficacy and safety of Dara addition to the standard of care regimen, tested in Phase III trials, in patients with relapsed refractory MM (RRMM). Methods: We conducted a systematic literature search in four databases (PubMed, Embase, Cochrane, and Clinicaltrials.gov) using MeSH terms and keywords for multiple myeloma and Dara including trade names and generic names from date of inception to April 2020. Initial search revealed 587 articles. After excluding review articles, duplicates, and non-relevant articles, we included three phase III trials reporting daratumumab addition to the standard of care regimens for RRMM patients. Results: A total of 1521 patients out of 1533 enrolled patients were evaluated in three phase III randomized controlled trials. A total of 849 patients were evaluated in the Dara group and 684 patients were evaluated in the control group. Catja. C et al. (2019) studied the role of Dara + bortezomib (V) + dexamethasone (d) in RRMM pts (n=498) in phase III trial (CASTOR). Saad Z.U et al. (2019) underlined the efficacy of Dara + carfilzomib (K) and (d) in RRMM pts (n=466) in phase III trial (CANDOR), and Nizar J. Bahlis et al. (2020) studied Dara + lenolidamide (R) + d in RRMM pts (n=569) in phase III trial (POLLUX). The addition of Dara to Vd, Rd, and Kd group was significant in term of overall response rate (ORR): 85% vs 63% (P &amp;lt;0.0001), 93% vs 76% (P &amp;lt; 0.0001), and 84.3% vs 74.7% (p=0.004), and minimal residual disease (MRD) negative status ((10-⁵ sensitivity threshold, assessed by multipara metric flow cytometry) in bone marrow: 11.6% vs 2.4% (P=0.000034), 30.4% vs 5.3% (P&amp;lt;0.0001), and 12.5% vs 1.3% (p&amp;lt;0.0001) group, respectively. Moreover, addition of Dara to Vd, and Rd group also showed marked improvement in progression free survival (PFS): 48% vs 7.9% (HR, 0.31; 95% CI, 0.25-0.39, P &amp;lt;0.0001) at 18 months, 44.5% vs 17.5% at 44 months (HR, 0.44; 95% CI, 0.35-0.55; P &amp;lt; 0.0001), and OS: 61% vs 51% at three years, and 65% vs 57% at 42 months, respectively. However, PFS and OS in Dara-Kd group was not reached vs control group: Kd group (HR= 0.63, 95% CI, 0.46-0.85, p=0.0014). Significant toxicities mainly included neutropenia, anemia, and thrombocytopenia (table 2). Addition of Dara to standard care regimen (Vd and Rd) achieved superior outcomes in terms of ORR, PFS and OS, except Kd group, in which only ORR was improved as compared to control group. Combination of Dara plus standard care regimen improved MRD negative status in RRMM patients as compared to standard regimen. Conclusion: Treatment of RRMM with Dara plus standard care therapy (Vd, Rd, and Kd) has shown promising outcomes with improved efficacy and higher negative MRD status, providing a new benchmark for future studies. Disclosures Anwer: Incyte, Seattle Genetics, Acetylon Pharmaceuticals, AbbVie Pharma, Astellas Pharma, Celgene, Millennium Pharmaceuticals,: Honoraria, Research Funding, Speakers Bureau.

Minimal Residual Disease-Driven Treatment Intensification By Sequential Addition of Ibrutinib to Venetoclax in Relapsed/Refractory Chronic Lymphocytic Leukemia: Results of the Monotherapy and Combination Phases of the Improve Study

Minimal Residual Disease-Driven Treatment Intensification By Sequential Addition of Ibrutinib to Venetoclax in Relapsed/Refractory Chronic Lymphocytic Leukemia: Results of the Monotherapy and Combination Phases of the Improve Study

Oncofetal Protein SALL4 Is Highly Expressed in Myelodysplastic Syndrome Alongside with NAT10 and P53

Introduction: Myelodysplastic syndrome (MDS) is a group of heterogeneous diseases characterized by cytologic dysplasia and refractory cytopenias as a result of ineffective hematopoiesis. We have reported that oncofetal protein SALL4 can be used as a prognostic biomarker in MDS disease. SALL4 is a transcription factor that is important for development and embryonic stem cell properties. While SALL4 expression is down-regulated or absent in most adult tissues, SALL4 is re-expressed in various cancers. We have previously reported that aberrant expression of SALL4 can be detected in MDS and AML patients. Studies in murine models, as well as in human samples, have demonstrated that SALL4 is essential for leukemic cell survival and that SALL4 transgenic mice develop an MDS-like phenotype prior to transformation to AML, suggesting that SALL4 can be a driver of MDS/AML pathogenesis. However, SALL4 expression status and related pathway in bone marrow (BM) cells and relationship with somatic gene mutations in MDS patients has not been explored. In this study, we evaluated the expression of SALL4 and related factors using single-cell mass cytometry (CyTOF) and NanoString technology in MDS patients alongside with target sequence for MDS-related mutations. Materials and methods: We evaluated the expression of SALL4 using single-cell mass cytometry (CyTOF) utilizing 28 antibodies including surface lineage markers and intracellular proteins, such as p53, ki67, c-myc and pAKT to identify SALL4 expressed cells and related pathway in bone marrow (BM) for 10 MDS patients. SALL4 expression was also analyzed in formalin-fixed paraffin-embedded (FFPE) 14 patient samples utilizing two SALL4 probes designed for NanoString technology alongside with target sequence for MDS-related mutations. One probe only detects expression of SALL4A, which is full length SALL4, while the other probe can detect both SALL4A as well as its splicing variant SALL4B. We examined the expression of a panel of 17 known SALL4 downstream target genes. Results: First, we assessed an expression level of SALL4 using CyTOF in 10 MDS patients as compared with normal BM samples (N=5). We observed that Lin-CD34+CD38+ progenitor cells in 8 out of the 10 MDS patients had higher SALL4 expression levels, while the progenitor cells of normal BM cells did not express SALL4. Similar results were observed in Lin-CD34+CD38- hematopoietic stem cells, CD11b+ mature myeloid cells, CD19+ B cells, CD235+ erythroid cells. Conversely only 3 MDS patient had weak SALL4 expression in CD3+ T cells. Subsequently, we investigated the correlation with p53, ki67, c-myc and pAKT. SALL4 is only correlated with p53 (P=0.005), while others were not. Next, we also assessed an expression level of SALL4A and SALL4A&amp;B in 14 MDS patient bone marrow (BM) samples using Nanostring nCounter. We observed that 12 out of 14 MDS patients had higher SALL4 expression levels as compared with control normal BM samples (N=3). Next, we evaluated whether MDS patients expressed SALL4A, SALL4B, or both. Of the 14 MDS patients, 8 predominantly expressed SALL4A Of these 8 MDS patients, 5 harbored RNA splicing-related mutations, such as SF3B1 (N=4), U2AF1 (N=1). Only 1 out of 7 patients who predominantly expressed SALL4B demonstrated a splicing related mutation. Subsequently, we investigated the correlation between SALL4 and its known downstream targets. An expression of SALL4A is moderately correlated with CBLb (γ=0.53), CDH1 (γ=0.42) and NAT10 (γ=0.41). The expression of SALLA&amp;B is moderately correlated with NAT10 (γ=0.47) and RUNX1 (γ=0.46). NAT10 (N-acetyltransferase 10) has been reported to promote transcription of RNA polymerase I and is a critical regulator of p53 homeostasis. It was identified to be a potential SALL4 downstream target in our early Chip-seq studies. In the isogenic K562 cell lines with SALL4 overexpression, higher levels of NAT10 were observed, suggesting that NAT10 is one of the downstream targets of SALL4. Conclusions: Our study has demonstrated for the first time that 1) SALL4 was expressed in various MDS BM cells confirmed by CyTOF 2) there are SALL4 splicing variants in MDS patients, particularly with SF3B1 mutations 3) a novel SALL4/NAT10/p53 link has been identified in these MDS patients. Future studies on mechanism(s) and biological role(s) of SALL4 splicing variants in MDS are needed. Disclosures No relevant conflicts of interest to declare.

The Metabolomic Status of the Differentiating Myeloid Lineage in MDS with Low and High Bone Marrow Blast Counts

Despite its major role in cellular biology, metabolism has only recently acquired a principal role in the research of the most profound cellular cycle disturbance, cancerous transformation. Myelodysplastic syndromes (MDS), a massively heterogeneous group of Hematopoietic Stem/ Progenitor Cell (HSC/HPC) disorders lie at the interface of normal differentiation and malignant transformation and have thus drew great attention due to their polymorphic presentation and elusive pathophysiology. Failure to establish a direct etiopathogenic relationship with specific genetic aberrations, along with the novel finding of a highly deregulated HIF1 activity by several unrelated research groups worldwide, including ours, urged us to investigate the metabolomic status of human bone marrow derived differentiating myeloid lineage in comparison with one another as well as with control samples. BM aspiration samples collected from 14 previously untreated MDS patients (10 patients with &amp;lt;5% (1 SLD, 8MLD, 1del5q, group 1- G1) and 4 with &amp;gt;5% BM blasts (2 EB1, 2 EB2group 2 - G2)) and 5 age matched controls. Myeloid lineage cells were isolated through ficoll bilayer protocol. All samples contained homogenous myeloid lineage subpopulations, assessedthrough optical microscopy. Two different metabolite extraction protocols were applied. The one with the best metabolites yield (50% MeOH, 30% ACN, 20% H2O) was chosen. LC-MS/MS analysis was performed using UPLC 1290 system (Agilent Technologies) coupled to a TripleTOF 5600+ mass spectrometer (SCIEX) equipped with SWATH acquisition, SelexION technology and an electrospray ionization source (ESI). A threshold of a minimum of three samples expressing a given metabolite was set against data sparsity. Data tables were scaled by data centering and setting unit variance. Log2 Foldcalculation and PLS analysis were performed for the two datasets (positive and negative ion-modes). R2 and Q2 for positive ion-mode and negative-ion mode analyses were determined. Both datasets were merged in a unique data table by taking into account maximum absolute log2 foldvalues, when a metabolite was found in both datasets. Warburg effect was evidently present in both the G1 and G2 vs control comparisons, yet the role of this stem like aerobic glycolysis seems markedly different in the two groups. While in the G2 group it serves to rescue glucose from complete burn in the mitochondrion and thus shuts it towards nucleotide synthesis (Pentose Phosphate Pathway found upregulated) with the added benefit of increased reduced Glutathione synthesis and improved redox state, in the G1 group proves detrimental. This greatly variable effect of the same phenomenon in the cellular fate lies upon the quality and functionality of the cellular mitochondrial content. G2 precursors presented functional mitochondrial (decreased NAD/NADH and FAD/FADH2) contrary to the G1 ones (Table). Failing TCA cycle, with increased NAD/NADH and FAD/FADH2 ratios and markedly increased ADP/ATP levels leads to FAs accumulation due to failure of effective adequate β oxidation. The uncontrolled increase in the NAD/NADH ratio stimulates upper glycolysis into a turbo mode further increasing the ADP/ATP, depleting cellular energy contents, engaging it to a never-ending deadly metabolism. The enormous abundance of upper glycolytic intermediates is relieved through phospholipid and ceramide synthesis, all found massively upregulated in both the MDS vs control yet also in the G1 vs G2 comparisons. FAs, mostly phospholipid and ceramide accumulation, interrupt the mitochondrial membrane lipidome further incapacitating metabolic integrity and inducing their autophagic degradation which further stimulates the Warburg effect. This type of metabolic reprogramming is eventually targeted to epigenetic modifier production, increased S-adenosyl-methionine, the major methyl group donor, 2-HydroxyGlutarate, a potent epigenetic modifier and notorious oncometabolite, Acetyl-Lysine, the major acetyl- group donor, even glutathione. We therefore present a model of an uncontrolled Warburg effect which in the G1 group confers premature death of the hematopoietic precursors, the ineffective hematopoiesis of MDS. Yet, under the pressure of the vastly upregulated epigenetic modifiers cellular fate changes, the G1 precursors adapt and transform to the G2 ones yet eventually to Acute Myeloid Leukemia blasts. Table Disclosures Vassilopoulos: Genesis pharma SA: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Membership on an entity's Board of Directors or advisory committees; Gilead: Research Funding; Abbvie: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees.

The Prognostic Significance of Minimal Residual Disease in Multiple Myeloma in the Molecular Genetic Groups Msmart 3.0

Assessment of the role of genetic abnormalities and minimal residual disease (MRD) is an active developing area in hematology. The use of genetic methods makes it possible to predict the course of the disease and apply an individualized approach to antimyeloma therapy. At the same time, the identification of MRD after therapy determines possibility of relapse. Aim. To identify the prognostic potential of MRD in patients in the standard and high molecular risk groups. Materials and methods. We analyzed 72 patients with MM (median age was 59 years (range 37-80), male/female - 1.3:1). All patients received initial therapy with proteasome inhibitors and / or immunomodulators. High dose therapy (MEL200) and autologous stem cell transplantation (ASCT) was carried out 50 (69%) patients. Standard cytogenetic and FISH methods were used to stratify patients in risk groups of mSMART 3.0. The standard risk (SR) was established in 52 (72%) patients, the high risk (HR) - in 20 (28%) patients. The MFC MRD status of bone marrow was evaluated after 4-6 cycles of induction therapy or after ASCT with use of 5-colors flow cytometry. MRD-negative status (MRD-) was based on level of clonal plasma cells &amp;lt;10-4 in bone marrow sample. Results. The MRD- was reached in 36% (26/72) patients. The median of OS in MRD+ group was 104 months, in MRD- was 146 months (p=.01). The median of PFS in MRD+ group was 26 months, in MRD- was 70 months (p=.00021). 2-years PFS in MRD+ group was 56%, in MRD- group was 100% (p=.00021). We divided patients into the following groups for evaluation the effect of MRD on survival in risk groups: SR МRD+ 34/72 (47%), SR МRD- 18/72 (25%), HR МRD+ 12/72 (17%) and HR MFC МRD- 8/72 (11%). The median of OS in HR MRD+ group was 72 months, in SR MRD+ - 104 months, in HR MRD- - 146 months, in SR MRD- was not achieved (p=.02). The median of PFS in HR MRD+ group was 24 months, in SR MRD+ - 26 months, in HR MRD- - 68 months, in SR MRD- - 70 months (p=.003). The 2-years PFS in HR MRD+ group was 44%, in SR MRD+ group was 50% and in SR MRD- and HR MRD- groups were 100% (p=.003). Conclusion. The absence of MRD is the most important prognostic factor. The leveling of negative effect of genetic abnormalities become possible when the MRD-negative response status is achieved. Presumably, this is due to the elimination of clonal plasma cells owing to the use of optimal antimyeloma therapy which is based on the risk stratification. Disclosures Martynkevich: Pfizer: Honoraria, Speakers Bureau; BMS: Honoraria, Speakers Bureau; Novartis: Honoraria, Speakers Bureau. Shuvaev:Novartis: Honoraria, Speakers Bureau; BMS: Honoraria, Speakers Bureau; Pfizer: Honoraria, Speakers Bureau.

S2991 Gastric Myeloid Sarcoma as a Presentation of Relapsed Acute Myelomonocytic Leukemia - A Case Report

INTRODUCTION: Myeloid sarcoma is an extramedullary proliferation of myeloid blasts that may be associated with a concurrent myeloid neoplasm involving the bone marrow, but such an association is not required. In some cases, myeloid sarcoma may herald a relapse in a patient with previously treated disease. In others, it may be the first indication of acute leukemia. CASE DESCRIPTION/METHODS: A 48-year-old male presented with nausea, vomiting and epigastric pain. Physical examination showed tachycardia, and epigastric tenderness. Nine months earlier he was diagnosed with acute myelomonocytic leukemia; cytogenetics showed 47,XY,+8,t(9;11)(p21.3;q23.3). At that time, he was treated with standard induction therapy with the 7 + 3 regimen with Cytarabine and Daunorubicin followed by 3 cycles of High-Dose Cytarabine (HiDAC). Lab results showed pancytopenia including Leukopenia with 19% blasts. Peripheral blood flow cytometry showed 18% monoblasts. CT chest and abdomen revealed diffuse lobular thickening of the gastric wall, segmental thickening of the small bowel loops, and pancreatic, paraspinal, and infiltrative right ventricular wall masses. Upper GI endoscopy showed thickened gastric folds with a nodular mucosa. Gastric mucosal resection was performed, and biopsy showed abnormal blasts infiltrating through the mucosal glands, consistent with myeloid sarcoma. A bone marrow biopsy was consistent with relapsed AML. Urgent therapy was instituted however the patient suffered a cardiac arrest and resuscitation was unsuccessful. DISCUSSION: Myeloid sarcoma (aka granulocytic sarcoma, myeloblastoma, or chloroma) may present simultaneously with, or precede bone marrow disease and may be seen in relapse or as progression of a prior myeloproliferative neoplasm. The most common sites of isolated myeloid sarcoma are the skin, followed by mucous membranes, orbits, central nervous system, and other internal organs. Myeloid sarcoma is more common in pediatric AML, although the true incidence in adults is unknown. In adults, roughly one third of myeloid sarcomas present with concurrent myeloid disease, and one third have a history of a prior myeloid neoplasm. The presence of a myeloid sarcoma is diagnostic of AML, regardless of the bone marrow status, or blast count. The diagnosis of myeloid sarcoma should be restricted to tumors that form space-occupying lesions. The approach to treatment of patients with myeloid sarcoma without evidence of AML on bone marrow biopsy is similar to that for patients with overt AML.Figure 1.: CT Abdomen showing lobular thickening of the gastric wall.Figure 2.: Upper GI endoscopy showing thickened gastric folds with nodular mucosa in the gastric body. Findings are concerning of infiltrative malignancy.Figure 3.: High power (10x) view of Hematoxylin and Eosin stain of gastric body biopsy showing abnormal monoblasts infiltrating through the mucosal glands, consistent with myeloid sarcoma.

3134 – CHARACTERIZATION OF THE HEMATOPOIETIC STEM CELLS AND BONE MARROW MICROENVIRONMENT IN SICKLE CELL DISEASE PATIENTS

Little is known about the status of the bone marrow (BM) in Sickle Cell Disease (SCD) patients. In this study, we characterized the hematopoietic stem and progenitors (HSPC) and the stromal cells from BM aspirates of eight SCD patients before transplant in comparison with age-matched BM aspirates from healthy individuals. By using multiparametric flow analysis, we observed a group of SCD patients (n=4) with characteristics similar to controls, and a distinct group of SCD patients (n=4) that exhibited lower average frequency of CD34+ cells, HSCs, multipotent and lymphoid progenitors. Methylcellulose colony assays showed a decreased ability of the BM cells of these patients to form colonies compared to control BM. scRNA-seq analysis of sorted BM CD34+ cells from SCD patients indicated changes in the DNA damage and cell cycle regulatory pathways compared to controls. Interestingly, all SCD patients displayed an increase in the BM non-hematopoietic cells including CD45-/CD31+ and CD45-/CD105+ subsets compared to controls, suggesting a change in their BM stromal niche. In vitro, SCD BM-derived stromal cells revealed distinct gene expression patterns including an increase in inflammatory cytokine (IL-6) & cell death-related genes (p16 and Bax) but decrease expression of a pluripotent gene (Oct4). We also detected an increase of inflammatory regulators, miR-155, and miR-146 in all BM-derived stromal cells from SCD patients, which correlates with increased inflammatory gene expression in these cells. Finally, analysis of the BM biopsies revealed alterations in the stromal components as evidenced by an overall decrease in cellularity in some patients, and increased iron deposits and activated macrophages. Taken together, these preliminary data suggest that the BM cells and BM microenvironment of SCD patients are phenotypically & molecularly different from control BM. Further studies will clarify whether there are correlations between the severity of the disease and BM alterations and whether the BM status at pre-transplant may help in predicting engraftment and outcomes of BM transplants in SCD patients.

Malnutrition is a predisposing factor for developing recurrent fever following febrile neutropenia in children with acute lymphoblastic leukemia

IntroductionThe factors that predict recurrence of fever following defervescence (DS) during febrile neutropenia (FN) episode have not been studied. The objective was to estimate the incidence and risk factors for recurrent fever (RF) in children with FN during the intensive phase of acute lymphoblastic leukemia (ALL) treatment. MethodsThe study included 113 consecutive patients diagnosed with ALL. Total of 256 FN episodes in these patients between January 2016 and June 2017 were analysed retrospectively. RF was defined as recurrent febrile event with absolute neutrophil count <500/mm3 that developed after an afebrile interval of 24 h but not exceeding 7 days following a febrile neutropenia episode. ResultsRF developed in 38/256 FNE (14.85%). Evidence of documented focus of infection was observed in 26/38 RF. Risk factors associated with development of RF were: non-remission status of bone marrow, profound neutropenia, persistent neutropenia, clinically or microbiologically documented infection, severe underweight and documented weight loss. Multivariate analysis revealed significant association between RF and non-remission status of bone marrow, profound neutropenia and severe underweight. ConclusionSevere underweight, profound neutropenia and non-remission status of bone marrow predispose the development of RF. These patients require close observation and may require prolonged administration of antibiotics irrespective of DS status.

Exploration of the personalized immune checkpoint atlas of plasma cell dyscrasias patients using high‑dimensional single‑cell analysis.

Immune checkpoint blockade endows patients with unparalleled success in conquering cancer. Unfortunately, inter-individual heterogeneity causes failure in controlling tumors in many patients. Emerging mass cytometry technology is capable of revealing a multiscale onco-immune landscape that improves the efficacy of cancer immunotherapy. We introduced mass cytometry to determine the personalized immune checkpoint status in bone marrow and peripheral blood samples from 3 patients with multiple myeloma, amyloid light-chain amyloidosis, and solitary bone plasmacytoma and 1 non-hematologic malignancy patient. The expression of 18 immune regulatory receptors and ligands on 17 defined cell populations was simultaneously examined. By single-cell analyses, we identified the T cell clusters that serve as immunosuppressive signal source and revealed integrated immune checkpoint axes of individuals, thereby providing multiple potential immunotherapeutic targets, including programmed cell death protein 1 (PD-1), inducible co-stimulator (ICOS), and cluster of differentiation 28 (CD28), for each patient. Distinguishing the cell populations that function as providers and receivers of the immune checkpoint signals demonstrated a distinct cross-interaction network of immunomodulatory signals in individuals. These in-depth personalized data demonstrate mass cytometry as a powerful innovation to discover the systematical immune status in the primary and peripheral tumor microenvironment.

Evaluation of bone marrow hemopoiesis and the elemental status of the red bone marrow of chickens under introduction of copper to the organism.

The role of chemical elements in an organism is versatile and multifunctional. However, you should pay attention to the reaction of the organism on the introduction of chemical elements with different biological roles, which is predetermined by the physiological role of organs and body systems. These include the red bone marrow, which primarily responds to endogenous and exogenous factors by its functional significance. Analyzing the myelogram of birds after the various ways of copper NP introduction into the body and the different dosages, we found that, by the end of the experiment, the total numbers of bone marrow cells in all groups were lower than the initial values: in the second group-12.54% lower (p < 0.05), in third-26.32% lower (p < 0.001), for the fourth-14.75% lower (p < 0.05), with exception for the first experimental group where this index was 45.51% higher (р < 0.001). We revealed the following changes in the peripheral blood: the hemoglobin content by the end of the experiment was significantly higher than the initial values: by 18.63% for the first group (p < 0.01); 28.61% higher in the third group (p < 0.001); and 15.76% higher for the fourth (p < 0.01), except the animals of the second group (3.23% lower). The concentration of erythrocytes in all groups was higher than that of the background: by 24.56% (p < 0.001), by 3.37%, by 26.18% (p < 0.001), and by 14.85% (p < 0.01), respectively; the leukocyte concentration in the first group was 39.63% higher (p < 0.001), it remained at the level of the initial values in the other groups. The erythrocyte sedimentation rate in all groups increased by 2.4, 4.0, 2.01, and 1.86 times (p < 0.001), respectively. We revealed that the introduction of copper into an organism in the form of nanopowder both with feed and intramuscularly significantly caused an increase of the content of such elements as arsenic, copper, and silicon and a decrease of calcium, potassium, magnesium, phosphorus, boron, cobalt, iodine, lithium, sodium, zinc, tin, and strontium in the marrowy aspirate. Moreover, compared with the first group (p < 0.01), increasing doses of nanopowders caused a significant rise in the arsenic and tin concentrations and a decline of iodine and strontium. We found that copper nanoparticles ambiguously affect the bone marrow hemopoiesis of poultry; increasing the dose and changing the type of introduction activating the bone marrow hematopoietic function, in particular, granulocyto-, megakaryocyto-, and erythropoiesis.

Characteristics of Bone Marrow Progenitor Cells of C57BL/6N Mice after 30-Day Hindlimb Suspension and 12-Hour Readaptation to Support Loading

The functional status of bone marrow (BM) progenitor cells, which provide hematopoiesis and homeostasis of bone tissue, determines many processes which take a place in spaceflight (SF) and subsequent recovery to gravity. It is known that SF factors and simulation of their effects do irreversible damage to the pool of hematopoietic and stromal progenitor cells. Meanwhile, changes in the functional activity of BM progenitor cells after simulation of SF effects were more pronounced than in the case of a real SF. The aim of the study was to examine processes of recovery of the functional activity of BM progenitor cells during readaptaion to loading after 30-day hindlimb suspension. Studies were performed on three groups of male mice: vivarium control, suspension, and readaptation. The following characteristics were monitored: number of nucleated BM cells, immunophenotype, proliferative activity of stromal BM cells, number of hematopoietic colony-forming units (CFU), CFUs of fibroblasts, and differentiating capabilities of BM hematopoietic and stromal precursors. Hindlimb suspension resulted in decreased number of fibroblast and hematopoietic CFU, inhibition of spontaneous osteodifferentiation of stromal progenitors and decreased expression of stromal markers. The readaptaion period was accompanied with restoration of the functional activity of stromal progenitors, while complete recovery of hematopoiesis was not observed.