Effect of wheat-grain moxibustion on Wnt/β-catenin signaling pathway in bone marrow cell in mice with bone marrow inhibition / 中国针灸

OBJECTIVE@#To observe the effect of wheat-grain moxibustion at "Dazhui" (GV 14), "Zusanli" (ST 36) and "Sanyinjiao" (SP 6) on Wnt/β-catenin signaling pathway in bone marrow cell in mice with bone marrow inhibition, and to explore the possible mechanism of wheat-grain moxibustion in treating bone marrow inhibition.@*METHODS@#Forty-five SPF male CD1(ICR) mice were randomly divided into a blank group, a model group and a wheat-grain moxibustion group, 15 mice in each group. The bone marrow inhibition model was established by intraperitoneal injection of 80 mg/kg of cyclophosphamide (CTX). The mice in the wheat-grain moxibustion group were treated with wheat-grain moxibustion at "Dazhui" (GV 14), "Zusanli" (ST 36) and "Sanyinjiao" (SP 6), 3 moxa cones per acupoint, 30 s per moxa cone, once a day, for 7 consecutive days. The white blood cell count (WBC) was measured before modeling, before intervention and 3, 5 d and 7 d into intervention. After intervention, the general situation of mice was observed; the number of nucleated cells in bone marrow was detected; the serum levels of interleukin-3 (IL-3), interleukin-6 (IL-6) and granulocyte macrophage colony stimulating factor (GM-CSF) were measured by ELISA; the protein and mRNA expression of β-catenin, cyclinD1 and C-Myc in bone marrow cells was measured by Western blot and real-time PCR method.@*RESULTS@#Compared with the blank group, the mice in the model group showed sluggish reaction, unstable gait, decreased body weight, and the WBC, number of nucleated cells in bone marrow as well as serum levels of IL-3, IL-6, GM-CSF were decreased (P<0.01), and the protein and mRNA expression of β-catenin, cyclinD1 and C-Myc was decreased (P<0.01). Compared with the model group, the mice in the wheat-grain moxibustion group showed better general condition, and WBC, the number of nucleated cells in bone marrow as well as serum levels of IL-3, IL-6, GM-CSF were increased (P<0.01, P<0.05), and the protein and mRNA expression of β-catenin, cyclinD1 and C-Myc was increased (P<0.05).@*CONCLUSION@#Wheat-grain moxibustion shows therapeutic effect on bone marrow inhibition, and its mechanism may be related to activating Wnt/β-catenin signaling pathway in bone marrow cells, improving bone medullary hematopoiesis microenvironment and promoting bone marrow cell proliferation.

Avaliação dos efeitos modulatórios da hematopoese no envelhecimento: Papel das células tronco mesenquimais medulares / Evaluation of the modulatory effects of hematopoiesis during aging: Role of bone marrow mesenchymal stem cells

O envelhecimento é um processo fisiológico que traz consigo uma série de alterações no organismo que se estendem até o nível molecular. Diante disto, este é um processo complexo que afeta diversos tecidos, sendo um deles o hematopoético, local onde, através de interações da Célula Tronco Hematopoética (CTH) com o ambiente ao seu redor, incluindo a Célula Tronco Mesenquimal (CTM), ocorre a hematopoese. Embora já sejam descritas na literatura algumas alterações na medula óssea consequentes do envelhecimento, os mecanismos por trás de tais mudanças permanecem elusivas, principalmente no âmbito das interações celulares ocorrentes na medula óssea. Portanto, este trabalho buscou investigar como o envelhecimento afeta a regulação hematopoética no contexto de sua relação com as CTM medulares. Para esta pesquisa, foram utilizados camundongos machos isogênicos da linhagem C57BL/6, dividindoos em grupos conforme sua idade: jovens (3 ­ 5 meses) e idosos (18 ­ 19 meses). Foi realizada a caracterização do modelo através de aspectos físicos como consumo proteico, variação de peso, entre outros, seguido de avaliação bioquímica e hematológica. Adicionalmente, foram coletadas células medulares e, posteriormente, realizado o isolamento das CTMs. Para estudar a relação destas células com a hematopoese, foram realizados ensaios in vitro utilizando a linhagem celular leucêmica C1498 (TIB-49™, ATCC®) mantidas em contato com o sobrenadante das CTMs isoladas. Quanto aos parâmetros bioquímicos, os animais idosos apresentaram menores níveis de albumina, aspartato alanina transferase (ALT) e de triglicerídeos quando comparados aos animais jovens. Contrariamente, os animais idosos apresentaram um maior nível de colesterol. Na avaliação hematológica, foi constatado pelo hemograma que os animais idosos apresentaram valores comparáveis aos animais jovens, todavia, o mielograma mostrou menor celularidade geral, seguido de menor número de células da linhagem eritroide e maior número de precursores granulocíticos. Através da imunofenotipagem, foi revelado um maior número de CTHs e de precursores grânulosmonocíticos na medula de animais idosos quando comparado aos jovens, e uma menor frequência de progenitores linfoides. Na imunofenotipagem de sangue periférico de animais idosos houve uma redução no número de linfócitos B e de eritrócitos, e aumento na população de células natural killers. Na imunofenotipagem de CTMs, o marcador CD73 apresentou menor expressão nos animais idosos. Avaliando o secretoma destas células estromais, foram encontrados no sobrenadante de CTMs de animais idosos aumentos significativos nas concentrações de CXCL12 e SCF e redução de IL-11. No âmbito molecular, as CTMs de animais idosos apresentaram aumento na expressão de Akt1, Nos e Ppar-γ, e redução na expressão de Csf3 e Cdh2. Adicionalmente, quando comparado a ação das CTMs de animais idosos em relação as CTMs de animais jovens, observou-se que CTMs de animais idosos foram capazes de aumentar a expressão de Sox2, Pou5f1 e Nanog e diminuir a expressão de Cdkn1a de células da linhagem C1498. O sobrenadante de CTMs de animais idosos também resultou na maior proliferação e migração de células da linhagem C1498. Portanto, levando em consideração a importância das CTMs sobre a regulação do sistema hematopoético, pode-se concluir que, no envelhecimento, as CTMs criam um ambiente propício para a proliferação celular no qual a manutenção da pluripotência é estimulada, o que pode acarretar em uma desregulação do sítio hematopoético quando habitado por células malignas

Aging is a physiological process in which occurs a series of alterations in an organism that extend to a molecular level. It is a complex process that affects various tissues, one of them being the bone marrow, wherethrough the interactions of the hematopoietic stem cell (CTH) with its surrounding environment, including with the mesenchymal stem cell (CTM), hematopoiesis takes place. Although some aging-associated alterations in the bone marrow can be found described in the literature, the mechanisms behind said changes remain elusive, especially when regarding the cellular interactions present inside the bone marrow. Therefore, this research aimed to investigate how aging affects the regulation of hematopoiesis in the context of its interactions with bone marrow-derived CTMs. For this investigation, male isogenic C57BL/6 mice were used as animal models. These were separated in two groups according to their age: young (3 ­ 5 months) and aged (18 ­ 19 months). The animal models were characterized by their physical properties such as protein intake and weight variation, followed by biochemical and hematological evaluation. Bone marrow cells were obtained and identified through immunophenotyping, thus isolating different cell populations, including the CTMs. To study the relationship between these cells and hematopoiesis, in vitro assays were conducted utilizing the leukemic cell lineage C1498 (TIB-49™, ATCC®) maintained in contact with the supernatant of isolated CTMs. By their biochemical profile, aged mice showed lower levels of albumin, alanine-aspartate transferase (ALT) and triglycerides compared to the young group. In contrast, aged mice had a higher cholesterol level. Hematological evaluation by total blood count showed similar results between the two groups, however, the myelogram revealed that the aged animals had lower cellularity, with less frequent cells from the erythroid lineage, with an increase in granulocytic precursors. Through immunophenotyping, it was also revealed that aged mice have higher numbers of hematopoietic stem cells, while also being noted a reduced population of lymphoid progenitors. An increase in the granulomonocytic progenitors was also found. Immunophenotyping peripheral blood cells of aged mice revealed reduced numbers of B lymphocytes and erythrocytes, and an increased natural killer cell population. Additionally, the cell surface marker CD73 was found to be less expressed in aged mice CTMs. The secretome of these stromal cells obtained from aged mice showed higher levels of CXCL12 and SCF, and lower levels of IL-11when compared to the young counterparts. At a molecular level, CTMs obtained from aged mice expressed more Akt1, Nos and Ppar-γ, while the expression of Csf3 and Cdh2 was reduced. Additionally, when comparing the effects of aged mice CTMs with young mice CTMs, it was observed that the first expressed were capable of increasing the expression of Sox2, Pou5f1 and Nanog, while decreasing Cdkn1a expression in the C1498 cell lineage. The supernatant obtained from aged mice also favored the proliferation and cell migration of the C1498 cell line. Thus, considering the importance that CTMs have over the hematopoietic system, we can conclude that, in aging, CTMs create a special environment which favors cell proliferation and maintenance of pluripotency, which can result in a dysregulation of the hematopoietic tissue when malignant cells are present

Research Progress of Clonal Hematopoiesis of Indeterminate Potential in Multiple Myeloma --Review / 中国实验血液学杂志

With the progress of medical technology, cloning hematopoietic was found to be widely exist in normal people. Because of its clinical significance and prognosis is unclear, it is named clonal hematopoiesis of indeterminate potential(CHIP), which has been detected in blood diseases such as myelodysplastic syndrome and lymphoma, and proven to be related to poor prognosis. Recently, CHIP has been also detected in patients with multiple myeloma (MM). In this article, the definition and influencing factors of CHIP, clinical significance, prognosis and treatment in MM were reviewed.

Síndromes mielodisplásicos y sistema inmunitario / Myelodysplastic Syndrome and Immune System

Introducción: Los síndromes mielodisplásicos constituyen un grupo heterogéneo de desórdenes hematológicos clonales adquiridos, que afectan la célula madre. Se caracterizan morfológicamente por: hematopoyesis ineficaz, citopenias periféricas progresivas, displasia en uno o más linajes celulares y tendencia evolutiva a leucemia aguda. Los avances recientes en la comprensión de los mecanismos genéticos y moleculares de los síndromes mielodisplásicos, han revelado la asociación entre alteraciones inmunológicas y las mutaciones recurrentes. Las células de la respuesta inmune innata y adaptativa, así como diversos mediadores solubles liberados por ellas, pueden establecer una respuesta antitumoral protectora o, por el contrario, inducir eventos de inflamación crónica que favorezcan la promoción y progresión de esta enfermedad. Objetivos: Resumir los conocimientos actuales de la relación sistema inmune-síndromes mielodisplásicos, enfatizando en las células inmunes del microambiente de la médula ósea y su importancia en la clínica de la enfermedad. Métodos: Se realizó investigación bibliográfica-documental acerca del tema. Se consultaron las bases de datos Scielo y Pubmed. Conclusiones: La comprensión de la función dual que ejerce el sistema inmune en los síndromes mielodisplásicos, constituye un desafío y son necesarios estudios clínicos rigurosos para poder establecer el valor de la manipulación del sistema inmune como una forma posible de tratamiento de esta enfermedad(AU)

Introduction: Myelodysplastic syndromes (MDS) constitute a heterogeneous group of acquired clonal hematological disorders that affect the stem cell. These are characterized morphologically and clinically by: ineffective hematopoiesis, progressive peripheral cytopenia, dysplasia in one or more cell lineages, in most of cases and evolutionary tendency to acute leukemia. Recent advances in understanding the genetic and molecular mechanisms of MDS have revealed the association between immunological alterations and recurrent mutations. Cells of the innate and adaptive immune response, as well as various soluble mediators released by them, can establish a protective antitumor response or, on the contrary, induce events of chronic inflammation that favor the promotion and progression of this disease. Objective: To summarize the current knowledge of the immune system-MDS relationship, emphasizing the immune cells of the bone marrow microenvironment and their importance in the clinic of the disease. Methods: A bibliographic-documentary research was carried out on the subject. The Scielo and Pubmed databases were consulted. Conclusions: Understanding the dual role of the immune system in MDS constitutes a challenge and rigorous clinical studies are necessary to establish the value of manipulating the immune system as a possible form of treatment of this disease(AU)

Regulation of RNA Binding Protein Mbnl1 on Development of Mouse Embryonic Hematopoietic Stem Cells / 中国实验血液学杂志

OBJECTIVE@#To analyze the dynamic molecular expression characteristics of single cell RNA binding proteins (RBPs) in the development of mouse embryonic hematopoitic stem cells (HSCs), and obtain the functional research target RNA splicing factor--Mbnl1, to clarify the function of Mbnl1 involved in regulating mouse embryonic HSC development.@*METHODS@#Bioinformatics was used to analyze the single-cell transcriptome data of mouse embryos during HSC development, and the single-cell RBP dynamic molecular expression maps in HSC development was obtained. Mbnl1 was obtained by combining differential analysis and literature research screening. The Mbnl1-knockout mouse model was constructed by the CRISPER/Cas9 technology. Aorta-gonad-mesonephros (AGM) and yolk sac (YS) tissue in two genotype embryos of Mbnl1@*RESULTS@#The in vitro CFU-C experiment of hematopoietic cells preliminarily indicated that there was no significant difference in the number of cell colonies in AGM region and YS transformed by the two genotypes of Mbnl1@*CONCLUSION@#Through functional experiments in vivo and in vitro, it has been confirmed that knockout of the RNA splicing factor--Mbnl1 does not affect the development of HSPC in AGM region of mouse embryo.

Application and Research Progress of Lineage Tracing in Differentiation Mechanism of Hematopoietic Stem Cells--Review / 中国实验血液学杂志

Hematopoietic stem cells (HSCs) reside at the top of the hierarchy and have the ability to differentiate to variety of hematopoietic progenitor cells (HPCs) or mature hematopoietic cells in each system. At present, the procress of HSC and HPC differentiating to the complete hematopoietic system under physiological and stressed conditions is poorly understood. In vivo lineage tracing is a powerful technique that can mark the individual cells and identify the differentiation pathways of their daughter cells, it takes as a strong technical system to research HSC. Traditional lineage tracing studies mainly rely on imaging techniques with fluorescent dyes and nucleic acid analogs. Recently, newly cell tracing technologies have been invented, and the combination of clonal tracing and DNAsequencing technologies have provided a new perspective on cell state, cell fate, and lineage commitment at the single cell level. In this review, these new tracing methods were introduce and discuss, and their advantages over traditional methods in the study of hematopoiesis were summarized briefly.

Research Advance of the Roles of N6-methyladenosine in the Regulation of Hematopoiesis--Review / 中国实验血液学杂志

There are more than 150 types of chemical modifications in RNA, mainly methylation, which are widely distributed in all kinds of RNA, including messenger RNA, transfer RNA, ribosomal RNA, non-coding small RNA and long non-coding RNA. In recent years, the identification of RNA methylation modification enzymes and the development of high-throughput sequencing technology at transcriptome level laid a foundation for revealing the expression and function of genes regulated by chemical modification of RNA. In this review, the most recent advances of RNA methylation, especially N6-methyladenosine (m

Anemia sideroblástica una enfermedad infrecuente de causas múltiples / Sideroblastic anemia, a rare disease of multiple causes

Introducción: La anemia sideroblástica es un trastorno hematológico que altera el proceso de la hematopoyesis, en la cual se ve afectada en mayor proporción la línea eritroide. Además, se presentan alteraciones en la síntesis del grupo hemo por disfunción mitocondrial en las células de la médula ósea. Objetivo: Indagar sobre la anemia sideroblástica, sus variables y los diferentes tipos de presentación que puede tener esta enfermedad. Métodos: Se llevó a cabo una revisión de la literatura en las bases de datos MEDLINE, EMBASE, Lilacs y ScienceDirect, con los descriptores: anemia sideroblástica, hematopoyesis, anomalías congénitas y 5-aminolevulinato sintetasa, en español e inglés. Se seleccionaron 26 artículos relacionados. Se hizo un análisis y resumen de la bibliografía revisada. Análisis y síntesis de la información: Es una enfermedad de origen congénito o secundario a otros procesos como el consumo de alcohol o inducido por algunos medicamentos. Se presenta con poca frecuencia y, en su mayoría, el diagnóstico se hace mediante estudios de laboratorio, como extendido de sangre periférica, estudio de médula ósea, a los que se les pueden aplicar diversas tinciones, realizar secuenciación o incluso realizar reacción en cadena de polimerasa. Conclusión: La anemia sideroblástica es una enfermedad puede relacionarse con otras alteraciones hematológicas que modifican el metabolismo del hierro. El tratamiento curativo es la trasfusión de hemocomponentes y debe hacerse un enfoque individualizado de cada paciente según el tipo de anemia sideroblástica(AU)

Introduction: Sideroblastic anemia is a hematological disorder that alters the hematopoiesis process. This condition affects, to a great extent, the erythroid line. In addition, alterations occur in the synthesis of the heme group due to mitochondrial dysfunction in the bone marrow cells. Objective: To investigate sideroblastic anemia, its variables and the different types of presentation of this disease. Methods: A literature review was carried out in the MEDLINE, EMBASE, Lilacs and ScienceDirect databases, using the descriptors anemia sideroblástica [sideroblastic anemia], hematopoyesis [hematopoiesis], anomalías congénitas [congenital anomalies] and 5-aminolevulinato sintetasa [5-aminolevulinate synthetase], in Spanish and English. Twety-six articles related to the topic were selected. An analysis and summary of the revised bibliography was carried out. Information analysis and synthesis: It is a disease of congenital origin or secondary to other processes such as alcohol consumption or induced by some medications. It occurs infrequently and its diagnosis is mostly made through laboratory studies, such as peripheral blood smear and bone marrow study, to which various stains can be applied, as well as sequencing or even polymerase chain reaction. Conclusion: Sideroblastic anemia is a disease that can be related to other hematological alterations that modify iron metabolism. The curative treatment is the transfusion of blood components. An individualized approach should be used according to the type of sideroblastic anemia(AU)

Hematopoietic Stem Cells Differentiate into the Megakaryocyte Lineage--Review / 中国实验血液学杂志

Abstract　　Hematopoietic stem cells are able to self-renewal and differentiate to all blood lineages. With the development of new technologies, recent studies have proposed the revised versions of hematopoiesis. In the classical model of hematopoietic differentiation, HSCs were located at the apex of hematopoietic hierarchy. During differentiation process, HSCs progressively lose self-renewal potential to be commited to progenitors with restricted differentiation potential. For instance, HSCs first give rise to multipotent progenitor cells, then produce bipotent and unipotent progenitors, and finally differentiate to mature blood cells. For the differentiation of megakaryocytes, common myeloid progenitors derived from HSCs give rise to megakaryocyte-erythrocyte progenitors and then develop to megakaryocytes. However, recent results show that megakaryocytes can be directly generated from HSCs without multipotent or bipotent phases. Alternatively, platelet-biased HSCs produce megakaryocyte progenitors. In this article, recent advances in the hematopoiesis and megakaryocyte differentiation pathway are reviewed.

PDGFRα Cell-Derived SCF Regulates Hematopoiesis of Adult Mice / 中国实验血液学杂志

OBJECTIVE@#To investigate the effect of PDGFRα stromal cells derived SCF on hematopoiesis of adult mice.@*METHODS@#Pdgfrα-CreER; R26-tdTomato mice model was constructed, and the proportion and distribution of PDGFRα cells in the liver, spleen, lung, kidney and bone marrow were analyzed by flow cytometry and confocal microscopy. Then the Pdgfrα-CreER; Scf mice model was further constructed, the Scf in PDGFRα was knocked out specifically, the effect of Scf-knocked out in PDGFRα stromal cells in the propitiation of HSPCs in the bone marrow was analyzed by flow cytometry. The effect of SCF on the proportion on number of peripheral blood cells in mice was analyzed by whole blood analyzer.@*RESULTS@#After Scf was knocked out in PDGFRα stromal cells, the propitiation and number of LKS- cell, LKS+ cell, HSC, MPP1, MKP, PreGM, PreMegE, and CFU-E in the bone marrow of mice was decreased, as well as in the number of red blood cells and hemoglobin concentration of peripheral blood. However, Scf knocked out from PDGFRα cells showed no effect on the hematopoiesis in spleen.@*CONCLUSION@#specific knocked out of Scf in PDGFRα stromal cells in adult mice can decrease the proportion of HSPCs in the bone marrow and the number of red blood cells in peripheral blood, and finally lead to anemia in mice.

Síndromes MonoMAC e Emberger em paciente com mutação no gene GATA2 / MonoMAC and Emberger syndromes in a patient with GATA2 mutation

As mutações que ocorrem no gene GATA2 podem ocasionar um amplo espectro de doenças genéticas. Os pacientes podem ter anormalidades na hematopoiese, na linfangiogenesis e na resposta imunológica. Os fenótipos incluem algumas síndromes caracterizadas por monocitopenia e infecção por micobactéria (síndrome MonoMac), síndrome mielodisplásica familiar, leucemia mieloide crônica ou aguda, síndrome de Emberger (linfedema primário), e mais raramente neutropenia, anemia aplástica e deficiência isolada de células NK. A idade da apresentação clínica pode variar desde a infância até a idade adulta. A deficiência autossômica dominante de GATA2 pode permanecer clinicamente silenciosa por décadas, ou mesmo durante toda a vida. Descrevemos o caso de uma jovem brasileira que apresentou a maioria dos problemas ligados à mutação no gene GATA2, observando-se as duas síndromes: MonoMAC e Emberger.

GATA2 mutations may cause a wide spectrum of genetic disorders. Patients may have several abnormalities in hematopoiesis, lymphangiogenesis and immune response. The phenotypes include monocytopenia and mycobacterial infection (MonoMAC) syndrome, familial myelodysplastic syndrome (MDS), chronic or acute myeloid leukemia (CML or AML), Emberger syndrome and, more rarely, neutropenia, aplastic anemia and isolated NKcell deficiency. Age at clinical onset ranges from early childhood to late adulthood. Autosomal dominant GATA2 deficiency may remain clinically silent for decades or even for life. We report a case of a Brazilian young patient who had most of the problems related to GATA2 mutation as well as MonoMAC and Emberger syndromes.

CCAAT/enhancer-binding protein alpha (CEBPA) gene haploinsufficiency does not alter hematopoiesis or induce leukemia in Lck-CALM/AF10 transgenic mice

Although rare, CALM/AF10 is a chromosomal rearrangement found in immature T-cell acute lymphoblastic leukemia (T-ALL), acute myeloid leukemia, and mixed phenotype acute leukemia of T/myeloid lineages with poor prognosis. Moreover, this translocation is detected in 50% of T-ALL patients with gamma/delta T cell receptor rearrangement, frequently associated with low expression of transcription factor CCAAT/enhancer-binding protein alpha (CEBPA). However, the relevance of CEBPA low expression for CALM/AF10 leukemogenesis has not yet been evaluated. We generated double mutant mice, which express the Lck-CALM/AF10 fusion gene and are haploinsufficient for the Cebpa gene. To characterize the hematopoiesis, we quantified hematopoietic stem cells, myeloid progenitor cells, megakaryocyte-erythrocyte progenitor cells, common myeloid progenitor cells, and granulocyte-macrophage progenitor cells. No significant difference was detected in any of the progenitor subsets. Finally, we tested if Cebpa haploinsufficiency would lead to the expansion of Mac-1+/B220+/c-Kit+ cells proposed as the CALM/AF10 leukemic progenitor. Less than 1% of bone marrow cells expressed Mac-1, B220, and c-Kit with no significant difference between groups. Our results showed that the reduction of Cebpa gene expression in Lck-CALM/AF10 mice did not affect their hematopoiesis or induce leukemia. Our data corroborated previous studies suggesting that the CALM/AF10 leukemia-initiating cells are early progenitors with lymphoid/myeloid differentiating potential.

HIV and haematopoiesis

Human immunodeficiency virus (HIV) infection not only leads to a compromised immune system, but also disrupts normal haematopoiesis, resulting in the frequent manifestation of cytopenias (anaemia, thrombocytopenia and neutropenia). Although there is a definite association between the severity of cytopenia and HIV disease stage, this relationship is not always linear. For example, cytopenias such as thrombocytopenia may occur during early stages of infection. The aetiology of these haematological abnormalities is complex and multifactorial, including drug-induced impaired haematopoiesis, bone marrow suppression due to infiltration of infectious agents or malignant cells, HIV-induced impaired haematopoiesis, and several other factors. In this review, we describe the frequencies of anaemia, thrombocytopenia and neutropenia reported for HIV-infected, treatment-naïve cohorts studied in eastern and southern sub-Saharan African countries. We present a rational approach for the use of diagnostic tests during the workup of HIV-infected patients presenting with cytopenia, and discuss how HIV impacts on haematopoietic stem/progenitor cells (HSPCs) resulting in impaired haematopoiesis. Finally, we describe the direct and indirect effects of HIV on HSPCs which result in defective haematopoiesis leading to cytopenias

Role of Rictor in Hematopoietic Stem Cells during Fetal Liver Hematopoiesis / 中国实验血液学杂志

OBJECTIVE@#To investigate the effect of Rictor on the hematopoiesis of fetal liver by specific knock-out of Rictor in hematopoietic cells of Vav-Cre mice.@*METHODS@#E12.5 0.08ee fetal liver cells from the experimental group Vav-Cre; Rictor embryos and control group Rictor or Rictor embryos were transplanted to recipients respectively to observe the effect of Rictor on reconstitution ability of hematopoietic stem cells. In the meantime, E14.5 0, 10, 20, 40, 60, 80 sorted hematopoietic stem cells from the Vav-Cre; Rictor fetal liver of experimental group and Rictor or Rictor fetal liver of control group were transplanted in to recipients to analyze the numbers of functional hematopoietic stem cells after Rictor was knocked-out. Furthermore, the self-renewal capacity was investigated by secondary transplantation of BM cells from primary recipients that had been successfully repopulated with E12.5 fetal liver-derived cells and by cell cycle analysis.@*RESULTS@#All the recipients receiving E12.5 Rictor or Rictor cells were repopulated (8/8, from 2 independent experiments) with an average chimerism of 77.2%±11.1% at 4 months post-transplantation, which resulted in 57 LT-RU per FL. In comparison, 8 out of 8 recipients receiving Vav-Cre; Rictor cells were repopulated with significantly reduced chimerism (37.0%±16.3%) (P＜0.01), which was equivalent to 8 LT-RU per FL. The limiting dilution transplantation experiment showed that there was one functional hematopoietic stem cell out of 17 sorted SLAM cells in the control group, and one functional hematopoietic stem cell out of 39 sorted SLAM cells in the experimental group. The secondary transplantation experiments showed that 2 out of 4 recipients were reconstructed in the control group after 1 month, and 0 was reconstructed in the experimental group by transplanting 4×10 donor cells respectively. What＇s more, the percentage of S/G/M cells in the experimental group increased when compared with controls.@*CONCLUSION@#In the process of fetal liver hematopoiesis, the specifically knocking-out the Rictor in hematopoietic system can lead to defect of reconstitution ability, decrease of the functional hematopoietic stem cell numbers and reduction of self-renewal ability of hematopoietic stem cells.

Tet2 regulates the function of mesenchymal stem cells / 生物工程学报

Tet2 (member 2 of the Tet family) plays an important role in DNA demethylation modification, epigenetic regulation, and hematopoiesis. In our previous study, we found that Tet2 knockout mice progressively developed lymphocytic leukemia and myeloid leukemia with aging. However，the role of Tet2 in bone marrow microenvironment is unclear. Here in this study, we found that more Tet2-/- mesenchymal stem cells (MSCs) from bone marrow were in the G2/M cell cycle stages. The division time of Tet2-/- MSCs was shorter than that of the control cells. The growth rate of Tet2-/- MSCs was accelerated. The cobblestone area-forming cells assay (CAFC) showed that Tet2 knockout MSCs supported the expansion of hematopoietic stem cells (HSCs) and the differentiation of HSCs was skewed towards myeloid cells. Through the dot blotting experiment, we found that the total methylation level was increased in Tet2-/- bone marrow cells (BM). We used the methylation-chip to analyze the methylation level of Tet2-/- bone marrow cells and found that the level of methylation was increased in the transcriptional starting area (TSS), exons (EXONS) and 3' untranslated region (3' UTR). Moreover, we found that the cytokines secreted by Tet2-/- MSCs, such as IL-8 and IL-18, were decreased. While the expressions of GM-CSF and CCL-3, which supported hematopoietic stem cells to differentiate to myeloid cells, were increased in Tet2-/- MSCs. Our results demonstrated that Tet2 regulates MSCs to support hematopoiesis.

Emerging role of Mitochondria in Maintenance of Hematopoietic Stem Cells--Review / 中国实验血液学杂志

Mitochondria are double-membrane organelles existing only in eukaryotic cells. Mitochondria perform various important functions，such as producing energy，regulating signal transduction，and contributing to stress response. Recent studies have highlighted an important role of mitochondria in the determination of hematopoietic stem cells （HSC） fate. Limited biogenesis or timely clearance of mitochondria is an important way against oxidative stress，which favors the quiescence of HSC. Accumulation of mitochondria may lead to proliferation of HSC，even the aging of HSC. Mitochondrial signaling regulates Ca concentration，which is essential for HSC differentiation. This review summarizes the current findings of the mitochondrial roles in HSC quiescence，self-renewal，lineage differentiation and aging.

Epigenetic Regulation and Epigenomic Landscape in Normal Physiological Hematopoiesis--Editorial / 中国实验血液学杂志

Abstract　　The physiological hematopoiesis depends on the programmed expression of a series of gene regulated by mechanisms at various levels. Currently, the epigenetic regulation has been considered as the most important mechanism during hematopoietic differentiation, resulting in a specific epigenomic landscape in the hematopoietic stem/progenitor cells. We try to concisely review the epigenetic mechanisms, including the genomic methylation, the histone modifications and the expression profiles of noncoding RNA, illustrating briefly the differentiation from the hematopoietic stem/progenitor cells to to the erythroid, myeloid and lymphoid cells.

Association between human T cell leukemia virus 1 (HTLV-1) infection and advanced periodontitis in relation to hematopoietic activity among elderly participants: a cross-sectional study

BACKGROUND@#We reported that human T cell leukemia virus 1 (HTLV-1) infection is positively associated with atherosclerosis. Recent evidence has revealed a close association of periodontitis with atherosclerosis, endothelial dysfunction, and disruption of the microcirculation. However, the association between HTLV-1 and advanced periodontitis has not been investigated to date. Since hematopoietic activity is closely linked to endothelial maintenance activity and is known to decline with age, we hypothesized that the state of hematopoietic activity influenced the association between HTLV-1 and advanced periodontitis in elderly participants.@*METHODS@#A cross-sectional study was performed including 822 elderly participants aged 60-99 years who participated in a dental health check-up. Advanced periodontitis was defined as a periodontal pocket ≥ 6.0 mm. Participants were classified as having low or high hematopoietic activity according to the median values of reticulocytes.@*RESULTS@#HTLV-1 infection was positively related to advanced periodontitis among participants with lower hematopoietic activity (lower reticulocyte count), but not among participants with higher hematopoietic activity (higher reticulocyte count). The adjusted odds ratio (95% confidence interval) considering potential confounding factors was 1.92 (1.05-3.49) for participants with a lower reticulocyte count and 0.69 (0.35-1.36) for participants with a higher reticulocyte count.@*CONCLUSIONS@#Among elderly participants, the association between HTLV-1 infection and advanced periodontitis is influenced by hematopoietic activity. Since hematopoietic activity is associated with endothelial maintenance, these findings provide an efficient tool for clarifying the underlying mechanism of the progression of periodontitis among elderly participants.

Perivascular Cells and NADPH Oxidase Inhibition Partially Restore Hyperglycemia-Induced Alterations in Hematopoietic Stem Cell and Myeloid-Derived Suppressor Cell Populations in the Bone Marrow

BACKGROUND AND OBJECTIVES: Patients suffer from long-term diabetes can result in severe complications in multiple organs through induction of vascular dysfunctions. However, the effects of chronic hyperglycemic conditions on hematopoiesis and the microenvironment in the bone marrow (BM) are not yet well understood. METHODS: BM cells were harvested from femurs of mice and analyzed using flow cytometry. Human PVCs were cultured in serum-free α-MEM. After 24hrs, PVC-CM was collected and filtered through a 0.22 μm filter. RESULTS: In this study, we showed that hyperglycemia alters hematopoietic composition in the BM, which can partially be restored via paracrine mechanisms, including perivascular cells (PVCs) and NADPH oxidase (NOX) inhibition in mice with streptozotocin-induced diabetes. Prolonged hyperglycemic conditions resulted in an increase in the frequency and number of long-term hematopoietic stem cells as well as the number of total BM cells. The altered hematopoiesis in the BM was partially recovered by treatment with PVC-derived conditioned medium (CM). Long-term diabetes also increased the number of myeloid-derived suppressor cells in the BM, which was partially restored by the administration of PVC-CM and diphenyleneiodonium (DPI), a NOX inhibitor. We further showed the downregulation of ERK and p38 phosphorylation in BM cells of diabetic mice treated with PVC-CM and DPI. This may be associated with dysfunction of hematopoietic cells and promotion of subsequent diabetic complications. CONCLUSIONS: Our data suggested that alterations in BM hematopoietic composition due to prolonged hyperglycemic conditions might be restored by improvement of the hematopoietic microenvironment and modulation of NOX activity.