Immature Cells Research Articles

Elucidating granulocytic myeloid-derived suppressor cell heterogeneity during Staphylococcus aureus biofilm infection.

Myeloid-derived suppressor cells (MDSCs) are pathologically activated immature myeloid cells with immunosuppressive activity that expand during chronic inflammation, such as cancer and prosthetic joint infection (PJI). Myeloid-derived suppressor cells can be broadly separated into 2 populations based on surface marker expression and function: monocytic myeloid-derived suppressor cells (M-MDSCs) and granulocytic myeloid-derived suppressor cells (G-MDSCs). Granulocytic myeloid-derived suppressor cells are the most abundant leukocyte infiltrate during PJI; however, how this population is maintained in vivo and cellular heterogeneity is currently unknown. In this study, we identified a previously unknown population of Ly6G+Ly6C+F4/80+MHCII+ MDSCs during PJI that displayed immunosuppressive properties ex vivo. We leveraged F4/80 and MHCII expression by these cells for further characterization using cellular indexing of transcriptomes and epitopes by sequencing, which revealed a distinct transcriptomic signature of this population. F4/80+MHCII+ MDSCs displayed gene signatures resembling G-MDSCs, neutrophils, and monocytes but had significantly increased expression of pathways involved in cytokine response/production, inflammatory cell death, and mononuclear cell differentiation. To determine whether F4/80+MHCII+ MDSCs represented an alternate phenotypic state of G-MDSCs, Ly6G+Ly6C+F4/80-MHCII- G-MDSCs from CD45.1 mice were adoptively transferred into CD45.2 recipients using a mouse model of PJI. A small percentage of transferred G-MDSCs acquired F4/80 and MHCII expression in vivo, suggesting some degree of plasticity in this population. Collectively, these results demonstrate a previously unappreciated phenotype of F4/80+MHCII+ MDSCs during PJI, revealing that a granulocytic-to-monocytic transition can occur during biofilm infection.

Neuronal IGF-1 overexpression restores hippocampal newborn cell survival and recent CFC memory consolidation in Cav1.3 knock-out mice

Insulin-like growth factor-1 (IGF-1) exogenously supplied in the brain was shown to enhance the survival of hippocampal dentate gyrus (DG) newborn cells and some cognitive functions of mice. This study aims to test whether IGF-1 requires Cav1.3 activity critically while enhancing newborn cell survival and cognitive functions. We used Cav1.3 KO mice, where both DG newborn cell survival and the recent (1 day) single-trial contextual fear conditioning (CFC) memory consolidation were impaired. To supply IGF-1, we overexpressed (OX) IGF-1 in DG mature neurons by injecting an adeno-associated virus (AAV-IGF-1-mCherry) into the hippocampal areas of Cav1.3 KO mice. Our results, first, confirmed the enhanced expression of IGF-1 in the DG granule cell layer by immunohistochemistry. Next, we found this IGF-1 OX resulted in fully restoring both the survival rate of DCX (+) newborn cells and the recent single-trial CFC memory formation in Cav1.3 KO mice. Our results show that IGF-1 can enhance the survival of DG immature newborn cells and the recent CFC memory formation in a Cav1.3 channel-independent manner in vivo, suggesting activation of complementary pathways including the Cav1.2 channel. The result will help the application of adult newborn cell-based therapy improve the cognitive functions of neurological disorders.

The miR-34b/MEK/ERK pathway is regulated by NR5A1 and promotes differentiation in primary bovine Sertoli cells

Sertoli cells play a key role in testicular development and spermatogenesis. It has been suggested that Sertoli cells differentiate after their proliferation ceases. Our previous study showed that miR-34b inhibits proliferation by targeting MAP2K1 mediated MEK/ERK signaling pathway in bovine immature Sertoli cells. Subsequent studies have revealed that the differentiation marker androgen receptor is upregulated during this process. However, the effect of the miR-34b/MEK/ERK pathway on immature bovine Sertoli cell differentiation and the underlying molecular mechanisms are yet to be explored. In this study, we determined that the miR-34b/MEK/ERK pathway was involved in the differentiation of primary Sertoli cells (PSCs) in response to retinoic acid. Transfection of an miR-34b mimic into PSCs promoted cell differentiation, whereas transfection of an miR-34b inhibitor into PSCs delayed it. Pharmacological inhibition of MEK/ERK signaling by AZD6244 promoted PSCs differentiation. Mechanistically, miR-34b promoted PSCs differentiation by inhibiting the MEK/ERK signaling pathway. Through a combination of bioinformatics analysis, dual-luciferase reporter assay, quantitative real-time PCR, and western blotting, nuclear receptor subfamily 5 group A member 1 (NR5A1) was identified as an upstream negative transcription factor of miR-34b. Furthermore, NR5A1 knockdown promoted Sertoli cell differentiation, whereas NR5A1 overexpression had the opposite effect. Together, this study revealed a new NR5A1/miR-34b/MEK/ERK axis that plays a significant role in Sertoli cell differentiation and provides a theoretical and experimental framework for further clarifying the regulation of cell differentiation in bovine PSCs.

Gansui Banxia decoction modulates immune-inflammatory homeostasis to ameliorate malignant ascites in rats

Background“Gansui Banxia decoction” (GBD) is a classical traditional Chinese medicine formula for treating abnormal accumulation of fluid, such as malignant ascites (MA). Although GBD has shown definite water-expelling effects, its exact underlying mechanism has not been elucidated. PurposeThis study aimed to investigate the drug effects of GBD on MA rats and its underlying mechanisms. MethodsThe main chemical composition was determined by ultra-high performance liquid chromatography. The drug effects of GBD was evaluated in the established cancer cell-induced MA rat model. The symptoms were analyzed, and biological samples were collected for detecting immune and inflammation-related indicators by enzyme-linked immunosorbent assays, western blot, and flow cytometry. ResultsGBD increased urine discharge, decreased ascites production, and alleviated cachexia. After GBD treatment, the expression of TLR4, MyD88, and NF-кB and the release of pro-inflammatory cytokines such as interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α were reduced. In addition, GBD increased G1 phase arrest and inhibit excessive proliferation of cells in bone marrow while alleviating G1 phase arrest and increasing proliferation of cells in the thymus. Correspondingly, the development and maturation of T cells also changed. GBD increased the proportion of mature T-cells (CD4+CD8− and CD4−CD8+ single-positive (SP) T-cells), and decrease the proportion of immature cells (CD4+CD8+ double-positive (DP) T-cells and CD4−CD8− double-negative (DN) T-cells) in the blood or tumor microenvironment (TME, the ascites microenvironment). Finally, we further analysis of immune cell subsets, GBD decreased the proportion of immunosuppressive T-cells in the blood (CD4+CD25+Foxp3+T-cells) and TME (CD8+CD25+Foxp3+T-cells), and increased the proportion of anti-tumor immune cells (CD8+CD28+T-cells and NK cells) in the TME. ConclusionThese findings indicated that the drug effects of GBD were attributed to regulating the immune-inflammatory homeostasis, thereby mitigating the destruction of cancer cells and reducing the generation of ascites, which provided theoretical support for the clinical rational application and extended the scientific connotation of “water-expelling” of GBD.

Atypical CML: diagnosis and treatment.

Atypical chronic myeloid leukemia (aCML) is included in the group of myelodysplastic/myeloproliferative neoplasms by the International Consensus Classification and has been renamed as MDS/MPN with neutrophilia by the fifth edition of World Health Organization classification. It is always characterized by morphologic identification of granulocytic dysplasia with >10% circulating immature myeloid cells, 2 distinguished features that differentiate this disease among the others. Somatic mutations may help to diagnose but are not specifically pathognomonic of the disease, with the most detected including ASXL1, SETBP1, NRAS, KRAS, SRSF2, and TET2 and with low-frequency CBL, CSF3R, JAK2, and ETNK1. The genomic landscape of aCML has been recently unravelling, revealing that SETBP1 and ETNK1 are usually not ancestral but secondary events associated with disease progression. Unfortunately, until now, no consensus on risk stratification and treatment has been developed: Mayo Clinic prognostic score identified as adverse events age >67 years, hemoglobin level <10 g/dL, and TET2 mutations. Although some possible genetic markers have been identified, allogeneic transplant remains the only curative strategy.

Arsenic As a Therapy in Cancer: A Short Review

Acute myeloid leukemia (AML) is a cancer of the blood and bone marrow in which the bone marrow produces immature white blood cells, called myeloblasts. AML (acute myeloid leukemia) prevents these myeloblasts from developing into mature, healthy blood cells, as a result they accumulate and crowd out other healthy cells, such as red blood cells, white blood cells, and platelets. Sometimes acute myeloid leukemia(AML) can also spread to other organs, such as the brain, spinal cord, liver, or spleen. Without prompt treatment, AML can be life-threatening. There has been 2–3 cases per 100,000 people annually. Compared to women, men are more likely to experience it. acute myeloid leukemia(AML) makes up roughly 3% of all malignancies, with a median age of 32 years, according to the population-based Cancer Registry for Delhi. Among the various drugs for treatment of leukemia arsenic has been one of the most effective in treating it. Arsenic has been known as poison over 4000years.Long-term exposure to as has led to various adverse effects on health, but after the discovery of chemo therapeutic properties of As the understanding has been changed from poison to drug. Arsenic trioxide (ATO) is the most active antileukemia agent in treatment of acute promyelocytic leukemia(APL). Arsenic trioxide (ATO) cause degradation of PML RAR alpha promoting differentiation. Not only this but also arsenic induces apoptosis via mitochondrial caspase or formation of reactive oxygen species (ROS) and deleting GSH content of cell. This article focuses on the therapeutic effect of arsenic on acute myeloid leukemia

Brain tissue haemoglobin expression in saline-perfused vs non-perfused rodents

Haemoglobin beta (Hbb) and delta-aminolevulinate synthase 2 (Alas2) messenger RNA (mRNA) is mainly found in immature red blood cells, reticulocytes, and not in mature erythrocytes. However, these are also expressed in other tissues such as brain cells, mostly neurons. Therefore, exact quantification of neural tissue homogenates may be confounded by remaining blood in the brain vasculature that may give falsely high values of Hbb/Alas2 expression. To investigate and compare the contribution of local Hbb/Alas2 expression, we investigated mRNA expression locally in the hippocampus and prefrontal cortex, in post-sacrifice saline-perfused and non-perfused mice and rats. Although there was a higher level of Hbb/Alas2 transcripts in the non-perfused animals, there was a significant mRNA expression in perfused brains that could at most partially be explained by remaining blood. Finally, we suggest that saline-perfusion should be recommended for quantification of brain Hbb/Alas2 transcripts in homogenates.

Electroacupuncture promotes neurogenesis in the dentate gyrus and improves pattern separation in an early Alzheimer's disease mouse model

BackgroundImpaired pattern separation occurs in the early stage of Alzheimer’s disease (AD), and hippocampal dentate gyrus (DG) neurogenesis participates in pattern separation. Here, we investigated whether spatial memory discrimination impairment can be improved by promoting the hippocampal DG granule cell neogenesis-mediated pattern separation in the early stage of AD by electroacupuncture (EA).MethodsFive familial AD mutations (5 × FAD) mice received EA treatment at Baihui and Shenting points for 4 weeks. During EA, mice were intraperitoneally injected with BrdU (50 mg/kg) twice a day. rAAV containing Wnt5a shRNA was injected into the bilateral DG region, and the viral efficiency was evaluated by detecting Wnt5a mRNA levels. Cognitive behavior tests were conducted to assess the impact of EA treatment on cognitive function. The hippocampal DG area Aβ deposition level was detected by immunohistochemistry after the intervention; The number of BrdU+/CaR+ cells and the gene expression level of calretinin (CaR) and prospero homeobox 1(Prox1) in the DG area of the hippocampus was detected to assess neurogenesis by immunofluorescence and western blotting after the intervention; The gene expression levels of FZD2, Wnt5a, DVL2, p-DVL2, CaMKII, and p-CaMKII in the Wnt signaling pathway were detected by Western blotting after the intervention.ResultsCognitive behavioral tests showed that 5 × FAD mice had impaired pattern separation (P < 0.001), which could be improved by EA (P < 0.01). Immunofluorescence and Western blot showed that the expression of Wnt5a in the hippocampus was decreased (P < 0.001), and the neurogenesis in the DG was impaired (P < 0.001) in 5 × FAD mice. EA could increase the expression level of Wnt5a (P < 0.05) and promote the neurogenesis of immature granule cells (P < 0.05) and the development of neuronal dendritic spines (P < 0.05). Interference of Wnt5a expression aggravated the damage of neurogenesis (P < 0.05), weakened the memory discrimination ability (P < 0.05), and inhibited the beneficial effect of EA (P < 0.05) in AD mice. The expression level of Wnt pathway related proteins such as FZD2, DVL2, p-DVL2, CAMKII, p-CAMKII increased after EA, but the effect of EA was inhibited after Wnt5a was knocked down. In addition, EA could reduce the deposition of Aβ plaques in the DG without any impact on Wnt5a.ConclusionEA can promote hippocampal DG immature granule cell neogenesis-mediated pattern separation to improve spatial memory discrimination impairment by regulating Wnt5a in 5 × FAD mice.

Cytological features of human papillomavirus-infected immature squamous metaplastic cells from cervical intraepithelial neoplasia grade 2.

In reflex cytology, the presence of prominent nucleoli in immature metaplastic squamous cells (IM) may be underdiagnosed due to variations in interpretation. The aim of this study is to identify human papillomaviruses (HPVs) that infect IM clusters in cervical intraepithelial neoplasia 2 (CIN2) on Papanicolaou (Pap) smears to determine the cytological features of lesion-derived cells. Thirty-two patients with a simultaneous diagnosis of CIN2 on biopsy and high-grade squamous intraepithelial lesions (HSIL) on cytology as well as with IM clusters on HSIL smears were included. CIN2 tissues and HSIL and IM clusters on Pap smears were isolated by manual microdissection, and HPV types were identified by PCR-based genotyping. The nuclear area within the IM clusters was also measured. The median nuclear area of HPV-negative IM clusters was 48 μm2 , with a coefficient of variation (CV) of 0.20; those of HPV-positive clusters were 66 μm2 and 0.34, respectively. The cut-off values of the nuclear area and CV for HPV positivity were 62 μm2 and 0.25, respectively. IM clusters composed of cells with a nuclear area of more than twice that of neutrophils or cells with a wide variation in nuclear sizes are likely to be neoplastic cells caused by HPV.

The Death of Sperm Cells

Abstract A major factor affecting male fertility is excessive death of germ cells, both immature germ cells and mature spermatozoa. It can be due to various factors causing testicular and/or post-testicular damage, such as infections, obstructive conditions, toxins, oxidative stress, hormonal imbalance, hyperthermia, and anti-sperm antibodies. Massive death of spermatozoa leads to a high proportion of dead sperm cells in the ejaculate (necrozoospermia or necrospermia) while death of immature germ cells can lead to low sperm count (oligozoospermia or oligospermia). Cell death can occur both by necrosis and by apoptosis; in recent decades, it has been found that apoptosis of mature spermatozoa is not only possible but quite common, and can contribute to infertility. Treatment approaches are primarily directed to the underlying condition, i.e. removing the cause(s) of sperm cell death whenever possible, but include also attempts to bypass the cell death event by intracytoplasmic sperm injection with testicular spermatozoa.

Osmolar Modulation Drives Reversible Cell Cycle Exit and Human Pluripotent Cell Differentiation via NF-κВ and WNT Signaling.

Terminally differentiated cells are commonly regarded as the most stable cell state in adult organisms, characterized by growth arrest while fulfilling their specialized functions. A better understanding of the mechanisms involved in promoting cell cycle exit will improve the ability to differentiate pluripotent cells into mature tissues for both pharmacological and therapeutic use. Here, it demonstrates that a hyperosmolar environment enforces a protective p53-independent quiescent state in immature hepatoma cells and in pluripotent stem cell-derived models of human hepatocytes and endothelial cells. Prolonged culture in hyperosmolar conditions stimulates changes in gene expression promoting functional cell maturation. Interestingly, hyperosmolar conditions do not only trigger growth arrest and cellular maturation but are also necessary to maintain this maturated state, as switching back to plasma osmolarity reverses the changes in expression of maturation and proliferative markers. Transcriptome analysis revealed sequential stages of osmolarity-regulated growth arrest followed by cell maturation, mediated by activation of NF-κВ, and repression of WNT signaling, respectively. This study reveals that a modulated increase in osmolarity serves as a biochemical signal to promote long-term growth arrest and cellular maturation into different lineages, providing a practical method to generate differentiated hiPSCs that resemble their mature counterpart more closely.

Selective Manipulation of the Mitochondria Oxidative Stress in Different Cells Using Intelligent Mesoporous Silica Nanoparticles to Activate On-Demand Immunotherapy for Cancer Treatment.

Herein, the vitamin K2 (VK2)/maleimide (MA) coloaded mesoporous silica nanoparticles (MSNs), functional molecules including folic acid (FA)/triphenylphosphine (TPP)/tetrapotassium hexacyanoferrate trihydrate (THT), as well as CaCO3 are explored to fabricate a core-shell-corona nanoparticle (VMMFTTC) for on-demand anti-tumor immunotherapy. After application, the tumor-specific acidic environment first decomposed CaCO3 corona, which significantly levitates the pH value of tumor tissue to convert M2 type macrophage to the antitumor M1 type. The resulting VMMFTT would then internalize in both tumor cells and macrophages via FA-assisted endocytosis and free endocytosis, respectively. These distinct processes generate different amount of VMMFTT in above two cells followed by 1) TPP-induced accumulation in the mitochondria, 2) THT-mediated effective capture of various signal ions to cut off signal transmission and further inhibit glutathione (GSH) generation, 3) ions catalyzed reactive oxygen species (ROS) production through Fenton reaction, 4) sustained release of VK2 and MA to further enhance the ROS production and GSH depletion, which caused significant apoptosis of tumor cells and additional M2-to-M1 macrophage polarization via different processes of oxidative stress. Moreover, the primary tumor apoptosis further matures surrounding immature dendritic cells and activates T cells to continuously promote the antitumor immunotherapy.

Adjuvant treatment of canine splenic hemangiosarcoma with autologous dendritic cell therapy - a prospective, randomized double-blind study

Canine splenic hemangiosarcomas (HSA) are malignant mesenchymal tumors with a high tendency for metastasis. Median survival times after splenectomy followed by adjuvant chemotherapy usually range between 5 and 8 months. The aim of this prospective randomized double-blinded study was to examine the efficacy of a commercially available dendritic cell therapy (PetBioCell) following splenectomy. In addition, possible side effects of this therapy were evaluated. Twenty-one dogs with histologically confirmed splenic HSA without metastasis (stages I or II) were included in the study. Ten dogs received the dendritic cell therapy, and 11 dogs received a placebo. Injections were administered according to the manufacturer's instructions monthly for the first 3 months and then every 3 months until death. Survival times and toxicoses of both groups were compared. Follow-up data were available for all 21 patients; the observation period ranging until euthanasia or metastasis-related death. One patient that had received the dendritic cell therapy was euthanized due to prostatitis and experienced the longest survival time (668 days). One dog in the placebo-group lived for 448 days after splenectomy. The median survival times in the dendritic cell therapy and the placebo group amounted to 74 and 126 days, respectively. There was no significant difference in tumor-free interval (t(18) = 1.4, p = 0.911) and survival times (t(19) = -0.094, p = 0.463) between the 2 groups. Toxicoses reported in both groups were mild and self-limiting. Immunotherapy using autologous, immature and unprimed dendritic cells according to the PetBioCell method failed to show efficacy on tumor-free interval and survival time in the presented dog population with splenic hemangiosarcoma.

Cell-Cell Interactions in the Testis that Support Male Fertility

The testis has two important functions: the production of sperm for fertility and the synthesis and release of androgens, such as testosterone, that maintain sperm production, sexual function, health, and wellbeing. Sperm production takes place within the seminiferous tubules, supported by the somatic Sertoli cells, and is stimulated by gonadotrophins produced by the pituitary and androgens produced by the Leydig cells in the interstitium. Spermatogenesis is a highly complex and co-ordinated process regulated via cell-cell interactions between multiple cell types. Sertoli cells produce many factors, in a cyclic manner, that are required for germ cell development and, in turn, they receive signals from developing germ cells to maintain their function. Regulation of the spermatogenic cycle involves different cell types co-operating to produce a “pulse” of retinoic acid that stimulates immature germ cells to become committed to differentiation. Research in the past decade has shown that Sertoli cells do much more than regulate germ cell development; they maintain the development and function of peritubular myoid cells, the testicular vasculature and the Leydig cells. Sertoli cells send signals to interstitial immune cells to maintain an immunosuppressive environment and deposit thousands of proteins into the interstitium, including spermatid-specific proteins that likely help to promote peripheral immune tolerance. Leydig cells produce testosterone that acts on receptors in Sertoli cells to initiate and maintain spermatogenesis, and in peritubular myoid cells to support germ cell development. Leydig cells exist in a niche with specialised macrophages that can regulate Leydig cell function and steroidogenesis, highlighting that cross-talk between testis cells and the immune system is important for testis function. Defining the specific signals that operate between the different cell types that regulate key testis functions will help to uncover new therapies to support male fertility and testicular testosterone production over the life course.

Complex genetic and semen examination in patients with the disomy Y

Background. Among the syndromes with aneuploidy on the sex chromosomes (gonosomes), the Y chromosome dysomy presents the mildest phenotypic manifestation. Most 47,XYY patients are not developed reproductive system abnormalities. Some of them have spermatogenesis defects and in-/subfertility, but the prevalence of male infertility in patients with dysomy Y, is not known. The causes and factors of phenotypic variability, fertility disorders, the spermatogenesis and semen characteristics in patients with dysomy Y have not been sufficiently studied.Aim. A comprehensive genetic examination, assessment of the state of spermatogenesis and spermatological defects in patients with dysomy Y.Materials and methods. We examined 25 men with Y-chromosome dysomy. The age of the patients was 32 ± 10 (14–59) years. Chromosome analysis was performed on cultured peripheral blood lymphocytes using a standard cytogenetic method with GTG-staining. Fluorescent in situ hybridization was performed to analyze X and Y chromosomes, gonosomal mosaicism, as well as to evaluate sperm aneuploidy. The Y chromosome microdeletions were detected by multiplex polymerase chain reaction. A standard semen analysis was performed in accordance with the recommendations of the WHO Guidelines (2010). Quantitative karyological analysis of immature germ cells from the ejaculate sediment was performed according to our own previously developed method.Results. Non-mosaic dysomy Y was diagnosed in 22 patients, including 21 men with karyotype 47,XYY, and one patient with additional chromosomal anomality (Robertson translocation) – karyotype 46,XYY,der(13;14)(q10;q10). XYY/XY mosaicism was revealed in two patients, one has a complex Y chromosome mosaicism with a complete the AZFc (b2/b4) deletion. Pathogenic Y chromosome microdeletions were not found in other patients. In one man, the presence of dysomy Y was suspected according to the results of quantitative fluorescent polymerase chain reaction, but according to the results of cytogenetic examination, the presence of an isodicentric chromosome Yq – karyotype 46,X,psu dic(Y)(p11.3) was detected. Using whole exome sequencing in one azoospermic patient, a heterozygous variant c.653G&gt;A(p.Gly218Asp) was detected in the SYCP2 gene, which encodes one of the proteins of the synaptonemal complex.Azoospermia (n = 9, 45 %), oligoastenoteratozoospermia (n = 6, 39 %), asthenoteratozoospermia (n = 3, 17 %), and asthenozoospermia (n = 2, 11 %) were diagnosed among 20 semen analysed patients. The volume of ejaculate was 2.7 ± 1.7 (1.0–5.0) ml, the concentration and total number of spermatozoa was 14.9 ± 21.8 (0.0–66.25), 50.4 ± 77.7 (0.0–265.0) mil lions, respectively. Oligospermia was observed in 2 (10%) patients. The quantitative karyological analysis of immature germ cells allowed to detect cryptozoospermia in azoospermic patinents and defects of prophase I of meiosis.Fluorescent in situ hybridization analysis revealed increased sperm aneuploidy (gonosomal dysomy and nullisomy, dysomy 18 and 21).Conclusion. Most of infertile men with dysomy Y are non-mosaic, and characterized by defected spermatogenesis (non-obstructive azoospermia or oligozoospermia), due to meiotic arrest at prophase I. Pathogenic AZFc deletion was found in a patient with complex Y chromosome mosaicism. Additional genetic factors of male fertility and spermatogenesis defects were found in some patients, which may explain the phenotypic variability.

Therapy-Related Acute Myeloid Leukemia After Chemotherapy For Osteosarcoma: Report of 2 Cases and Review of The Literature

Abstract Introduction/Objective Therapy-related acute myeloid leukemia (t-AML) and myelodysplastic syndrome (t-MDS) are rare but well-established late complications of chemotherapeutic agents or radiation therapy used to treat various malignancies. Many cases of t-AML/t-MDS have been described secondary to Hodgkin, non-Hodgkin lymphoma, and other solid tumors. However, only a few cases of t-AML and t-MDS have been reported following osteosarcoma treatment. We describe two patients diagnosed with osteosarcoma who developed t-AML after receiving multiple chemotherapeutic agents. Methods/Case Report A 12-year-old male with Li-Fraumeni syndrome was diagnosed with osteosarcoma of the left ilium and sacrum with pulmonary metastases. Despite multiple lines of chemoradiation therapy including doxorubicin and ifosfamide, tumor progressed at the primary tumor site. The patient subsequently presented with altered mental status and pancytopenia. Bone marrow biopsy demonstrated AML. He died despite supportive care. A 14-year-old female was diagnosed with left tibial osteosarcoma with bony and pulmonary metastases. She was treated on standard osteosarcoma chemotherapy including doxorubicin, cisplatin, methotrexate, ifosfamide and etoposide, surgery, and radiation. 1 year following therapy, she had local recurrence of osteosarcoma without progression despite not starting chemotherapy. However, 3 years later, she developed pancytopenia, and immature white blood cells were identified on peripheral smear. Bone marrow biopsy revealed AML-M7. Despite supportive care and zoledronic acid, she ultimately died from sepsis and disseminated intravascular coagulation. Results (if a Case Study enter NA) NA Conclusion With improved therapy and survival for osteosarcoma patients, these patients should be monitored for secondary malignancies. T-AML is rare following osteosarcoma treatment, but outcome remains poor, despite treatment. Underlying Li-Fraumeni syndrome may influence the risk of development of secondary malignant neoplasms. Literature review of types and prognosis of t-AML following osteosarcoma will be reviewed and compared to our cases, including related genetic predisposing factors and chemotherapeutic agents. Our second patient is the first reported case of AML-M7 secondary to osteosarcoma treatment.

A Deep Learning Framework for Classification of Immature White Blood Cells in Acute Myeloid Leukemia Using Convolutional Autoencoder and Transfer-Learning Ensemble

Acute myeloid leukemia (AML) is a type of acute leukemia that affects myeloid cells. It is characterized by uncontrolled proliferation of immature WBCs causing an accumulation of immature WBCs in the bone marrow and peripheral circulation. AML is an aggressive cancer that can be life-threatening if not treated promptly, therefore, early detection is crucial. Identification of immature WBCs and their subtypes is the first step towards AML diagnosis. Microscopic blood smear image analysis is commonly used to diagnose AML as it is less expensive non-invasive diagnostic tool compared to bone marrow biopsy and immunophenotype. Nonetheless, classifying immature WBCs presents challenges due to their high similarity and minimal interclass variation, especially for intermediate stages of myelopoiesis which make is susceptible to misclassification. The current diagnostic methods of AML are based on manual identification of immature WBCs using peripheral blood smear. These methos are time-consuming, prone to errors, and subject to inter-observer variation. Therefore, this study aims to develop a computer-aided diagnostic framework to accurately identify immature WBCs and classify them into various subtypes. The proposed framework consists of two main components: a binary classification system to classify cells into mature versus immature cells and a multiclassification system to further classify immature cells into four subtypes including myeloblast, monoblast, and promyelocytes. The proposed framework was designed to undergo four distinct phases: the first phase involves preprocessing, which includes data augmentation techniques aimed at addressing the imbalance distribution of WBCs. Augmentation encompasses geometric transformation and generation of synthetic images using convolutional Autoencoder (CAE). Feature extraction phase involves using image embedding and transfer-learning. Image embedding representation was obtained using CAE and then utilized by two pre-trained models: VGG19 and Resnet50. Classification phase was carried out using weighted ensemble of the VGG19 and Resnet50 with the optimal weights determined through Grid search. The validation phase evaluated the model performance using overall accuracy, precision, and sensitivity. The area under the ROC curve (AUC) was used to assess model discrimination ability. The proposed framework demonstrated excellent results, achieving an average accuracy of 99.5%, a sensitivity of 97.97%, and a precision of 94.12%. The model exhibited an excellent discriminatory capability, with an AUC of 99.9%. Furthermore, the proposed framework outperformed previous methods, showcasing improved performance. Key word: Acute myeloid leukemia, peripheral blood smear, immature white blood cells, deep learning, feature extraction, computer-aided diagnosis.

Immune Signature in Telomere-Biology Disorders

Excessive telomere shortening caused by pathogenic germline variants in telomere-biology genes may result in bone marrow failure, hematopoietic malignancy and extramedullary complications, such as idiopathic pulmonary fibrosis (IPF), liver cirrhosis, and solid tumors. Patients with short telomeres also may develop immunodeficiency with low counts of T-cell receptor excision circles (TRECs), kappa-deleting excision circles (KRECs), and CD4 + T cells. The aim of the present study was to comprehensively determine the immune system changes in human patients with telomeropathies by deep-phenotyping peripheral blood mononuclear cells (PBMCs) and quantifying cytokine serum levels. We applied a 39-marker panel of metal-labeled antibodies and employed mass cytometry (CyTOF) to assess the subsets of lymphocytes, monocytes, and dendritic cells (DC) in 20 patients and 10 healthy individuals. High-dimensional analysis was conducted using automated clustering ( Flow-SOM) to identify subpopulations and cell states, whereas t-SNE was employed as a visualization tool. A total of 32 serum cytokines, chemokines and growth factors were quantified by a bead-based immunoassay (Luminex™). First, we confirmed previous findings of low CD4/CD8 ratio (0.73±0.56 vs. 1.3±0.69 in controls, p=0.05), and reduced absolute naïve (CD45RA +CCR7 +) CD4 + and CD8 + cell counts ( p&amp;lt;0.01), with effector memory cell accumulation in patients with telomere diseases, and the current study further showed a reduction in naïve B (CD19 +IgD +CD27 -) and in recent thymic emigrants (RTE), characterized by CD31 +CD45RA + ( p&amp;lt;0.01), indicating a consistent aged B and T cell profile. T H1, T H17 and T H17.1 CD4 + lymphocytes were reduced ( p&amp;lt;0.05), whereas the T H2/T H1 ratio was increased (1.6±0.83 vs. 0.82±0.39 in controls; p=0.013), demonstrating a dysregulated T helper cell diversity. T regs, on the other hand, did not appear to be affected. Plasmacytoid DCs (CD3 -CD141 +CD123 +CD1c -), which are known inducers of T helper differentiation, were reduced in patients ( p=0.014). A double negative T cell (DNT) population, characterized as CD3 +CD4 -CD8 -Vd2 -Tbet +Granzyme B +, was significantly increased ( p=0.0002). Activated effector memory and TEMRA CD4 + cells, also expressing exhaustion markers PD-1 and TIGIT (CD4 +CD45RA +/-CCR7 -CD38 +HLADR +Ki67 +PD-1 +TIGIT low) and proliferating switched memory B cells (CD3 -CD19 +IgD -CD27 +Ki67 +) were higher ( p=0.046 and p=0.041, respectively) suggesting the occurrence of an environment prone to immune activation, also supported by the prevalence of CD14 +CD16 +CXCR3 +CCR4 + classical monocytes ( p=0.0042). Additionally, mucosal-associated invariant T (MAIT) cells (CD3 +CD161 highVɑ7.2 +) were markedly reduced in patients ( p&amp;lt;0.0001), possibly due to their recruitment to other tissues as a response to inflammation. Conversely, immature NK cells (CD3 -CD19 -CD56 brightCD16 -) were more frequent in patients as compared to controls ( p=0.026), and individuals with the shortest telomere lengths had an even higher frequency of these cells. In addition to the previously described CD4 + immunodeficiency, the predominance of immature NK cells may potentially impact the immunosurveillance of malignant transformations. When an unsupervised clustering algorithm using cell subpopulations as variables was applied, patients and controls were correctly identified in 100% of cases. Telomere length positively correlated with some cytokine levels in serum. This was observed for angiopoietin-1, IL-1 superfamily, IL-3, IL-4, IL-7, IL-23, IL-27, M-CSF, MCP-1, MIP-3a and PDGF-BB. Taken together, our results reveal a distinct immunophenotype in telomeropathies, which comprises deficient or skewed maturation of certain subsets, an aged phenotype of B and T cells, aberrant lymphocyte activation and very low levels of circulating MAIT cells, which might be indicators of ongoing inflammatory processes, tied with dysregulated cytokine levels. This immune perturbance may contribute to the clinical onset of telomeropathies and increase the risk of infections, cirrhosis, IPF and cancer development.

Precise Single-Cell Transcriptomic Mapping of Leukemia Cell States Reveals Unconventional Lineage Priming in Acute Myeloid Leukemia

Initial disease classification within acute leukemia relies on identifying morphological and immunophenotypic features of hematopoietic differentiation retained by leukemic blasts. While existing approaches can classify leukemic cells into broad lineages, they lack precision in discerning between specific cell states, particularly at the level of immature blasts. Single-cell (sc) RNA-sequencing (RNA-seq) provides thousands of new markers to enable precise determination of leukemia cell state and provides an opportunity to refine our classification of acute leukemia. To extend our ability to identify leukemia cell states by scRNA-seq, we developed a comprehensive reference map of human bone marrow hematopoiesis. Specifically, we integrated three unsorted bone marrow datasets and three CD34+ hematopoietic stem and progenitor (HSPC) purified datasets to ensure balanced representation of early HSPCs and terminally differentiated immune cells. This culminated in a curated atlas of 263,159 high-quality sc transcriptomes, representing 55 cellular states spanning 45 healthy donors (Fig 1A). We validated our cell state annotations to ensure concordance between transcriptional states and functional populations through reference mapping of bulk and sc transcriptomes from purified HSPC subsets. For example, mapping of scRNA-seq profiles from Lin-CD34+38-45RA-90+49f+ long-term (LT) HSCs revealed 91% concordance between transcriptional HSC and functional LT-HSC. We next performed scRNA-seq profiling on 12 AML patient samples harbouring either myelodysplasia-related genetic features or classical alterations involving NPM1 or KMT2A. By mapping leukemia cells onto our reference atlas, we identified pronounced involvement of early erythroid-like blasts in a subset of AML samples. To further investigate unconventional lineage priming in AML, we processed and mapped scRNA-seq profiles from eleven studies comprising 166 additional AML samples and 9 mixed phenotype acute leukemia (MPAL) samples (Fig 1B). After quality control and exclusion of mature lymphoid cells, we performed composition analysis utilizing 600,570 leukemia cells mapped to 38 cell states to identify patterns of variation among leukemia cell states. Immature leukemia cells map to a range of cellular states spanning HSC/MPP-like, LMPP-like, MLP-like, GMP-like, MEP-like, and EarlyEry-like, among others. Notably, we identified a subset of AMLs with high MLP-like enrichment that co-cluster with MPALs as well as a subset with high EarlyEry-like involvement that co-cluster with acute erythroid leukemias (AEL), thus highlighting the biological continuum between these diseases. We next identified marker genes from each leukemia cell state and trained sparse regression models to estimate their relative abundance within bulk RNA-seq cohorts. Through bulk analysis, we confirmed that MPAL is highly enriched for MLP-like cells compared to AML (p=2.5e-12) and that M6 AELs are highly enriched for EarlyEry-like cells compared to M0-M5 AMLs (p=0.00067). Among 864 AML patients, we found that high MLP-like abundance was associated with NUP98-NSD1 fusions (p=0.0011) and RUNX1 mutations (p=8.0e-10) while high EarlyEry-like abundance was associated with Complex Cytogenetics (p=8e-15) and TP53 mutations (p=2.3e-25). Cellular states of immature leukemic cells captured inter-patient heterogeneity within 136 AEL samples, wherein high EarlyEry-like abundance was associated with TP53 mutations (p=3.6e-9) and Poor cytogenetic risk (p=1.1e-9) while high GMP-like abundance was associated with KMT2A alterations (p=0.00046) and Good/Intermediate risk (p=0.00032). Finally, through integration of sc transcriptomics and targeted DNA profiling, we found examples of genetic subclones impacting the cellular hierarchies of individual patients through induction of early differentiation blocks, skewing of lineage output from myeloid to erythroid, or potentiation of transcriptional self-renewal programs within mature myeloid cells. Together, our high-resolution mapping approach highlights the cellular state continuum between acute leukemias and enumerates the impact of genetic drivers on leukemia cell hierarchies. Precise definitions of cellular states, coupled with the presence or absence of genetic alterations, may help to refine future disease classification, prognostication, and therapy development.

Jak2V617F Bone Marrow Exposure Leads to Dysfunction of Normal NK Cells

Introduction: We have previously demonstrated a functional impairment of NK cells in the Jak2V617F murine model and peripheral blood cells from patients with Myeloproliferative Neoplasms, with emphasis on the increased frequency of immature NK cells and reduced cytotoxicity of the more mature CD27-CD11b+ fraction. It is not known whether MPN initiating cells are intrinsically resistant to tumor immunity or whether they can modify NK cells of the leukemic microenvironment, leading to dysfunction. Aims: To clarify these mechanisms, the present work aimed to model the leukemic exposure of normal NK cells and verify their modifications using a Jak2V617F chimeric transplant model. Methods: For transplantation, a non-myeloablative conditioning (single sublethal irradiation of 400cGy) was performed to partially preserve the recipient's hematopoiesis (50-60% of donor engraftment). 5 x 10 6 total bone marrow (BM) cells from Jak2VF or Jak2WT control animals (both C57BL/6, CD45.2) were injected retro-orbitally into wild-type mice (C57BL/6, CD45.1, N=6 per group). Engraftment was evaluated by flow cytometry according to CD45.2/CD45.1 differential ratio. After engraftment was confirmed, frequency, receptors, and functional subtypes of exposed NK cells were evaluated. NK cytotoxicity against YAC-1 target cells was evaluated after culture with serum and supernatant of whole BM from chimeric animals. Results: The frequency of host NK cells (CD45.1) exposed to Jak2VF BM was lower than that of NK cells exposed to Jak2WT BM (Jak2WT 44.05% vs Jak2VF 19.76%, p&amp;lt;0.0001). Evaluation of functional subtypes showed that host NK cells had a lower frequency of immature secretory (Jak2WT 44.32% vs Jak2VF 30.70%, p=0,0407) and higher frequency of tolerant (Jak2WT 12.43% vs Jak2VF 24.34%, p=0.0016) and cytotoxic (Jak2WT 7.15% vs Jak2VF 19.30%, p&amp;lt;0.0001) NK cells when exposed to leukemia than when exposed to normal BM. In comparison, secretory immature NK cells from the leukemic BM (CD45.2) were low numbered as compared to Jak2WT NK cells (Jak2WT 73.30% vs Jak2VF 35.74%, p&amp;lt;0.0001) and cytotoxic NK cells were more frequent (Jak2WT 7.28% vs Jak2VF 19.16%, p=0.0003). In addition, host NK cells presented decreased expression of the activating receptor DNAM-1 when exposed to leukemia than when exposed to normal BM (Jak2WT 51.20% vs Jak2VF 46.10%, p=0.0006), whereas CD244 and NKG2D activating receptors were not differentially expressed. In contrast, the expression of TIGIT (but not NKG2A) inhibitory receptor was increased after leukemia exposure (Jak2WT 14.83% vs 46.10%, p=0.0003). Regarding the effect of the leukemic medium on NK cells, cytotoxicity was not altered when WT NK cells were exposed to serum or BM supernatant from chimeric transplanted animals. However, NK cells exposed to Jak2VF chimeric serum were activated according to CD69 expression (Jak2WT 0.060% vs Jak2VF 0.30%, p=0.0114) but presented lower expression of the CD107a degranulation marker (Jak2WT 91.92% vs Jak2VF 62.34%, p=0.0075) than NK cells exposed to Jak2WT cells. Conclusions: Our findings demonstrated that leukemia exposure led to altered NK cell frequency and maturation distribution as demonstrated by reduced immature and an increased tolerant and cytotoxic fraction. Changes in the expression profile of activating and inhibitory receptors were also observed. Therefore, we concluded that the leukemic environment leads to NK dysfunction and that strategies that aim to control NK maturation and the interaction between stem cell ligands and functional NK receptors can be explored to restore immunosurveillance in JAK2V671F Myeloproliferative Neoplasms.