Special AT-Rich Sequence-Binding Protein 1 Supports Survival and Maturation of Naive B Cells Stimulated by B Cell Receptors.

Epigenetic mechanisms underpin the elaborate activities of essential transcription factors in lymphocyte development. Special AT-rich sequence-binding protein 1 (SATB1) is a chromatin remodeler that orchestrates the spatial and temporal actions of transcription factors. Previous studies have revealed the significance of SATB1 in T cell lineage. However, whether and how SATB1 controls B cell lineage development is yet to be clarified. In this study, we show that SATB1 is an important factor during splenic B cell maturation. By analyzing SATB1/Tomato reporter mice, we determined the dynamic fluctuation of SATB1 expression in the B cell lineage. Although SATB1 expression decreased to minimal levels during B cell differentiation in the bone marrow, it resurged markedly in naive B cells in the spleen. The expression was dramatically downregulated upon Ag-induced activation. Splenic naive B cells were subdivided into two categories, namely SATB1high and SATB1-/low, according to their SATB1 expression levels. SATB1high naive B cells were less susceptible to death and greater proliferative than were SATB1-/low cells during incubation with an anti-IgM Ab. Additionally, SATB1high cells tended to induce the expression of MHC class II, CD86, and CD83. Accordingly, naive B cells from B lineage-specific SATB1 conditional knockout mice were more susceptible to apoptosis than that in the control group upon anti-IgM Ab stimulation in vitro. Furthermore, conditional knockout mice were less capable of producing Ag-specific B cells after immunization. Collectively, our findings suggest that SATB1 expression increases in naive B cells and plays an important role in their survival and maturation.

[Adenocarcinoma with Aplastic Anemia as an Immune-related Adverse Event Caused by Pembrolizumab: Report of a Case].

A 74-year-old man was found a left completely atelectasis on chest X-ray. He had undergone left lower lobe resection because of an adenocarcinoma at the age of 58. Bronchoscopy revealed a tumor near the left upper lobe branch entry that obstructed the lumen, and a biopsy confirmed the diagnosis of adenocarcinoma. A left completion pneumonectomy was performed, but #4L and #10 lymph nodes could not be completely resected. Programmed cell death 1-ligand 1( PD-L1) was positive with tumor proportion score (TPS) 15%, so chemotherapy with pembrolizumab+pemetrexed+carboplatin was started about 1.5 months after surgery. Pancytopenia appeared from the seventh course and did not improve after discontinuation of chemotherapy, so we consulted to the hematologist. He was diagnosed as aplastic anemia by bone marrow biopsy. Aplastic anemia was unresponsive to treatment and chemotherapy could not be resumed. He died of exacerbation of lung cancer.

Autonomous TGFß signaling induces phenotypic variation in human acute myeloid leukemia.

Heterogeneity of leukemia stem cells (LSCs) is involved in their collective chemoresistance. To eradicate LSCs, it is necessary to understand the mechanisms underlying their heterogeneity. Here, we aimed to identify signals responsible for heterogeneity and variation of LSCs in human acute myeloid leukemia (AML). Monitoring expression levels of endothelial cell-selective adhesion molecule (ESAM), a hematopoietic stem cell-related marker, was useful to detect the plasticity of AML cells. While healthy human hematopoietic stem/progenitor cells robustly expressed ESAM, AML cells exhibited heterogeneous ESAM expression. Interestingly, ESAM- and ESAM+ leukemia cells obtained from AML patients were mutually interconvertible in culture. KG1a and CMK, human AML clones, also represented the heterogeneity in terms of ESAM expression. Single cell culture with ESAM- or ESAM+ AML clones recapitulated the phenotypic interconversion. The phenotypic alteration was regulated at the gene expression level, and RNA sequencing revealed activation of TGFß signaling in these cells. AML cells secreted TGFß1, which autonomously activated TGFß pathway and induced their phenotypic variation. Surprisingly, TGFß signaling blockade inhibited not only the variation but also the proliferation of AML cells. Therefore, autonomous activation of TGFß signaling underlies the LSC heterogeneity, which may be a promising therapeutic target for AML.

Novel insight into the correlation between hernia orifice of cystocele and lower urinary tract function: a pilot study.

BACKGROUND: It has been hypothesized that women with significant pelvic organ prolapse (POP), particularly of the anterior vaginal wall, may have voiding dysfunction (VD). Although the VD mechanism due to cystocele is not fully understood, different vaginal compartments have rarely been closely examined. This study attempted to further elucidate the correlation between POP and VD through a new subgroup classification using cystoscopy. METHODS: This study reviewed clinical records of 49 women who underwent cystocele repair. All patients were scheduled for laparoscopic sacrocolpopexy, preoperatively underwent uroflowmetry and postvoid residual urine volume (PVR) measurement, and completed pelvic floor function questionnaires. Bladder examination by cystoscopy was additionally performed using the lithotomy position with the Valsalva maneuver. RESULTS: Subjects were divided into four groups according to hernia orifice presence determined by cystoscopy, which included the trigone type, posterior wall type, trigone and urethra type, and trigone and posterior wall type. The posterior wall type had statistically higher PVR values versus the trigone and posterior wall type (P = 0.013). The posterior wall type had statistically lower values for average urine flow rate versus the urethra and trigone type (P = 0.020). There were no significant differences noted in the pelvic floor function questionnaires among the four groups. CONCLUSIONS: A new bladder defect classification based upon hernia orifice location was associated with lower urinary tract function. Posterior wall hernia presence caused significant voiding function deterioration. This new subgroup classification, which can more clearly identify and indicate bladder function, is also comparable among patients.

Identification of MS4A3 as a reliable marker for early myeloid differentiation in human hematopoiesis.

Information of myeloid lineage-related antigen on hematopoietic stem/progenitor cells (HSPCs) is important to clarify the mechanisms regulating hematopoiesis, as well as for the diagnosis and treatment of myeloid malignancies. We previously reported that special AT-rich sequence binding protein 1 (SATB1), a global chromatin organizer, promotes lymphoid differentiation from HSPCs. To search a novel cell surface molecule discriminating early myeloid and lymphoid differentiation, we performed microarray analyses comparing SATB1-overexpressed HSPCs with mock-transduced HSPCs. The results drew our attention to membrane-spanning 4-domains, subfamily A, member 3 (Ms4a3) as the most downregulated molecule in HSPCs with forced overexpression of SATB1. Ms4a3 expression was undetectable in hematopoietic stem cells, but showed a concomitant increase with progressive myeloid differentiation, whereas not only lymphoid but also megakaryocytic-erythrocytic progenitors were entirely devoid of Ms4a3 expression. Further analysis revealed that a subset of CD34+CD38+CD33+ progenitor population in human adult bone marrow expressed MS4A3, and those MS4A3+ progenitors only produced granulocyte/macrophage colonies, losing erythroid colony- and mixed colony-forming capacity. These results suggest that cell surface expression of MS4A3 is useful to distinguish granulocyte/macrophage lineage-committed progenitors from other lineage-related ones in early human hematopoiesis. In conclusion, MS4A3 is useful to monitor early stage of myeloid differentiation in human hematopoiesis.

Estrogen-inducible sFRP5 inhibits early B-lymphopoiesis in vivo, but not during pregnancy.

Mammals have evolved to protect their offspring during early fetal development. Elaborated mechanisms induce tolerance in the maternal immune system for the fetus. Female hormones, mainly estrogen, play a role in suppressing maternal lymphopoiesis. However, the molecular mechanisms involved in the maternal immune tolerance are largely unknown. Here, we show that estrogen-induced soluble Frizzled-related proteins (sFRPs), and particularly sFRP5, suppress B-lymphopoiesis in vivo in transgenic mice. Mice overexpressing sFRP5 had fewer B-lymphocytes in the peripheral blood and spleen. High levels of sFRP5 inhibited early B-cell differentiation in the bone marrow (BM), resulting in the accumulation of cells with a common lymphoid progenitor (CLP) phenotype. Conversely, sFRP5 deficiency reduced the number of hematopoietic stem cells (HSCs) and primitive lymphoid progenitors in the BM, particularly when estrogen was administered. Furthermore, a significant reduction in CLPs and B-lineage-committed progenitors was observed in the BM of sfrp5-null pregnant females. We concluded that, although high sFRP5 expression inhibits B-lymphopoiesis in vivo, physiologically, it contributes to the preservation of very primitive lymphopoietic progenitors, including HSCs, under high estrogen levels. Thus, sFRP5 regulates early lympho-hematopoiesis in the maternal BM, but the maternal-fetal immune tolerance still involves other molecular mechanisms that remain to be uncovered.

Fractalkine attenuates excito-neurotoxicity via microglial clearance of damaged neurons and antioxidant enzyme heme oxygenase-1 expression.

Glutamate-induced excito-neurotoxicity likely contributes to non-cell autonomous neuronal death in neurodegenerative diseases. Microglial clearance of dying neurons and associated debris is essential to maintain healthy neural networks in the central nervous system. In fact, the functions of microglia are regulated by various signaling molecules that are produced as neurons degenerate. Here, we show that the soluble CX3C chemokine fractalkine (sFKN), which is secreted from neurons that have been damaged by glutamate, promotes microglial phagocytosis of neuronal debris through release of milk fat globule-EGF factor 8, a mediator of apoptotic cell clearance. In addition, sFKN induces the expression of the antioxidant enzyme heme oxygenase-1 (HO-1) in microglia in the absence of neurotoxic molecule production, including NO, TNF, and glutamate. sFKN treatment of primary neuron-microglia co-cultures significantly attenuated glutamate-induced neuronal cell death. Using several specific MAPK inhibitors, we found that sFKN-induced heme oxygenase-1 expression was primarily mediated by activation of JNK and nuclear factor erythroid 2-related factor 2. These results suggest that sFKN secreted from glutamate-damaged neurons provides both phagocytotic and neuroprotective signals.

GM-CSF increases LPS-induced production of proinflammatory mediators via upregulation of TLR4 and CD14 in murine microglia.

BACKGROUND: Microglia are resident macrophage-like cells in the central nervous system (CNS) and cause innate immune responses via the LPS receptors, Toll-like receptor (TLR) 4 and CD14, in a variety of neuroinflammatory disorders including bacterial infection, Alzheimer's disease, and amyotrophic lateral sclerosis. Granulocyte macrophage-colony stimulating factor (GM-CSF) activates microglia and induces inflammatory responses via binding to GM-CSF receptor complex composed of two different subunit GM-CSF receptor α (GM-CSFRα) and common ß chain (ßc). GM-CSF has been shown to be associated with neuroinflammatory responses in multiple sclerosis and Alzheimer's disease. However, the mechanisms how GM-CSF promotes neuroinflammation still remain unclear. METHODS: Microglia were stimulated with 20 ng/ml GM-CSF and the levels of TLR4 and CD14 expression were evaluated by RT-PCR and flowcytometry. LPS binding was analyzed by flowcytometry. GM-CSF receptor complex was analyzed by immunocytochemistry. The levels of IL-1ß, IL-6 and TNF-α in culture supernatant of GM-CSF-stimulated microglia and NF-κB nuclear translocation were determined by ELISA. Production of nitric oxide (NO) was measured by the Griess method. The levels of p-ERK1/2, ERK1/2, p-p38 and p38 were assessed by Western blotting. Statistically significant differences between experimental groups were determined by one-way ANOVA followed by Tukey test for multiple comparisons. RESULTS: GM-CSF receptor complex was expressed in microglia. GM-CSF enhanced TLR4 and CD14 expressions in microglia and subsequent LPS-binding to the cell surface. In addition, GM-CSF priming increased LPS-induced NF-κB nuclear translocation and production of IL-1ß, IL-6, TNF-α and NO by microglia. GM-CSF upregulated the levels of p-ERK1/2 and p-p38, suggesting that induction of TLR4 and CD14 expression by GM-CSF was mediated through ERK1/2 and p38, respectively. CONCLUSIONS: These results suggest that GM-CSF upregulates TLR4 and CD14 expression in microglia through ERK1/2 and p38, respectively, and thus promotes the LPS receptor-mediated inflammation in the CNS.

The neuroprotective effects of milk fat globule-EGF factor 8 against oligomeric amyloid ß toxicity.

BACKGROUND: Phosphatidylserine receptor is a key molecule that mediates the phagocytosis of apoptotic cells. Milk fat globule-EGF factor 8 (MFG-E8) is a phosphatidylserine receptor that is expressed on various macrophage lineage cells, including microglia in the central nervous system (CNS). Targeted clearance of degenerated neurons by microglia is essential to maintain healthy neural networks. We previously showed that the CX3C chemokine fractalkine is secreted from degenerated neurons and accelerates microglial clearance of neuronal debris via inducing the release of MFG-E8. However, the mechanisms by which microglia produce MFG-E8 and the precise functions of MFG-E8 are unknown. METHODS: The release of MFG-E8 from microglia treated with conditioned medium from neurons exposed to neurotoxic substances, glutamate or oligomeric amyloid ß (oA ß) was measured by ELISA. The neuroprotective effects of MFG-E8 and MFG-E8-induced microglial phagocytosis of oA ß were assessed by immunocytochemistry. The effects of MFG-E8 on the production of the anti-oxidative enzyme hemeoxygenase-1 (HO-1) were determined by ELISA and immunocytochemisty. RESULTS: MFG-E8 was induced in microglia treated with conditioned medium from neurons that had been exposed to neurotoxicants, glutamate or oA ß. MFG-E8 significantly attenuated oA ß-induced neuronal cell death in a primary neuron-microglia coculture system. Microglial phagocytosis of oA ß was accelerated by MFG-E8 treatment due to increased CD47 expression in the absence of neurotoxic molecule production, such as tumor necrosis factor-α, nitric oxide, and glutamate. MFG-E8-treated microglia induced nuclear factor E(2)-related factor 2 (Nrf2)-mediated HO-1 production, which also contributed to neuroprotection. CONCLUSIONS: These results suggest that microglia release MFG-E8 in response to signals from degenerated neurons and that MFG-E8 protects oA ß-induced neuronal cell death by promoting microglial phagocytic activity and activating the Nrf2-HO-1 pathway. Thus, MFG-E8 may have novel roles as a neuroprotectant in neurodegenerative conditions.

Interleukin-34 selectively enhances the neuroprotective effects of microglia to attenuate oligomeric amyloid-ß neurotoxicity.

Microglia, macrophage-like resident immune cells in the brain, possess both neurotoxic and neuroprotective properties and have a critical role in the development of Alzheimer's disease (AD). We examined the function of Interleukin-34 (IL-34), a newly discovered cytokine, on microglia because it reportedly induces proliferation of monocytes and macrophages. We observed that the neuronal cells primarily produce IL-34 and that microglia express its receptor, colony-stimulating factor 1 receptor. IL-34 promoted microglial proliferation and clearance of soluble oligomeric amyloid-ß (oAß), which mediates synaptic dysfunction and neuronal damage in AD. IL-34 increased the expression of insulin-degrading enzyme, aiding the clearance of oAß, and induced the antioxidant enzyme heme oxygenase-1 in microglia to reduce oxidative stress, without producing neurotoxic molecules. Consequently, microglia treated with IL-34 attenuated oAß neurotoxicity in primary neuron-microglia co-cultures. In vivo, intracerebroventricular administration of IL-34 ameliorated impairment of associative learning and reduced oAß levels through up-regulation of insulin-degrading enzyme and heme oxygenase-1 in an APP/PS1 transgenic mouse model of AD. These findings support the idea that enhancement of the neuroprotective property of microglia by IL-34 may be an effective approach against oAß neurotoxicity in AD.

Inotuzumab ozogamicin and blinatumomab sequential therapy for relapsed/refractory Philadelphia chromosome-positive acute lymphoblastic leukemia.

To overcome the unfavorable outcome of refractory/relapsed (R/R) Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL) and conduct allogeneic stem cell transplantation (allo-SCT) safely, we designed a sequential therapy involving a single cycle of Inotuzumab ozogamicin (InO) and Blinatumomab (Blina). Two heavily treated and aged patients with R/R Ph+ALL were treated with the therapy. Both of them achieved complete molecular remission without cytokine release syndrome and underwent allo-SCT without veno-occlusive disease/sinusoidal obstruction syndrome. Although appropriate central nervous system prophylaxis should be added, the InO-Blina sequential therapy is a promising strategy for treating R/R Ph+ALL as a bridging regimen before allo-SCT.

Autoimmune-mediated thrombocytopenia after allogeneic hematopoietic stem cell transplantation: significance of detecting reticulated platelets and glycoprotein-specific platelet autoantibodies.

Autoimmune hematological disorders are rare complications after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Diagnosis of immune thrombocytopenia (ITP) is challenging, especially after allo-HSCT, because various complications such as graft-versus-host disease, disease relapse, viral infection, thrombotic microangiopathy, and drug side effects can also cause thrombocytopenia. Assessment of reticulated platelets (RP) and plasma thrombopoietin (TPO) levels may be useful to distinguish between ITP and hypoplastic thrombocytopenia. ITP is generally characterized by an increased percentage of RP, and a normal or slightly increased plasma TPO level. We now report three cases of thrombocytopenia after allo-HSCT. RP% was elevated in these patients, as it is in primary ITP. However, in contrast to primary ITP, plasma TPO levels were high in two of three patients. Anti-αIIbß3 and anti-GPIb/IX-specific direct IgG antibodies were detected as well, suggesting occurrence of immune-mediated platelet destruction in addition to bone marrow suppression in two patients. All three patients were successfully treated with corticosteroids and/or thrombopoietin receptor agonists (TPO-RAs). These results suggest that increased RP% and detection of glycoprotein-specific platelet autoantibodies are useful for the diagnosis of ITP after HSCT.

Microglia activated with the toll-like receptor 9 ligand CpG attenuate oligomeric amyloid {beta} neurotoxicity in in vitro and in vivo models of Alzheimer's disease.

Soluble oligomeric amyloid beta (oAbeta) 1-42 causes synaptic dysfunction and neuronal injury in Alzheimer's disease (AD). Although accumulation of microglia around senile plaques is a hallmark of AD pathology, the role of microglia in oAbeta1-42 neurotoxicity is not fully understood. Here, we showed that oAbeta but not fibrillar Abeta was neurotoxic, and microglia activated with unmethylated DNA CpG motif (CpG), a ligand for Toll-like receptor 9, attenuated oAbeta1-42 neurotoxicity in primary neuron-microglia co-cultures. CpG enhanced microglial clearance of oAbeta1-42 and induced higher levels of the antioxidant enzyme heme oxygenase-1 in microglia without producing neurotoxic molecules such as nitric oxide and glutamate. Among subclasses of CpGs, class B and class C activated microglia to promote neuroprotection. Moreover, intracerebroventricular administration of CpG ameliorated both the cognitive impairments induced by oAbeta1-42 and the impairment of associative learning in Tg2576 mouse model of AD. We propose that CpG may be an effective therapeutic strategy for limiting oAbeta1-42 neurotoxicity in AD.

Blockade of glutamate release from microglia attenuates experimental autoimmune encephalomyelitis in mice.

Multiple sclerosis (MS) is a chronic inflammatory demyelinating and neurodegenerative disease of the central nervous system. Despite a variety of anti-inflammatory or immunomodulation drugs including interferon-beta are effective to reduce relapse risk, most patients have progressive neurological deterioration due to axonal degeneration. Accumulation of activated microglia is a pathological hallmark of active MS lesion. Microglia can act as not only antigen-presenting cells but also effector cells to damage other cells in the central nervous system. Especially, glutamate released by activated microglia induces excito-neurotoxicity and may contribute to neurodegeneration in MS. Gap junction is a major cell-to-cell channel and is composed of paired hemichannels on coupled cells. Recent studies showed that cells release various small molecules (including ions, ATP, and amino acids) from unpaired hemichannel of gap junction that is openly exposed to the extracellular space. We have previously revealed that activated microglia produce glutamate via glutaminase and release it through hemichannels of gap junctions. Thus, in this study, we examined whether the glutaminase inhibitor and the gap junction blocker relieved experimental autoimmune encephalomyelitis (EAE) that is an animal model of MS. Here we show that the gap junction blocker carbenoxolone (CBX) and the glutaminase inhibitor 6-diazo-5-oxo-L-norleucine (DON) decreased glutamate release from activated microglia and rescued neuronal death in a dose-dependent manner in vitro. In EAE mice, treatment with CBX or DON also attenuated EAE clinical symptoms. Thus, blockade of glutamate release from activated microglia with CBX or DON may be an effective therapeutic strategy against neurodegeneration in MS.

Endothelial Cell-Selective Adhesion Molecule Contributes to the Development of Definitive Hematopoiesis in the Fetal Liver.

Endothelial cell-selective adhesion molecule (ESAM) is a lifelong marker of hematopoietic stem cells (HSCs). Although we previously elucidated the functional importance of ESAM in HSCs in stress-induced hematopoiesis in adults, it is unclear how ESAM affects hematopoietic development during fetal life. To address this issue, we analyzed fetuses from conventional or conditional ESAM-knockout mice. Approximately half of ESAM-null fetuses died after mid-gestation due to anemia. RNA sequencing analyses revealed downregulation of adult-type globins and Alas2, a heme biosynthesis enzyme, in ESAM-null fetal livers. These abnormalities were attributed to malfunction of ESAM-null HSCs, which was demonstrated in culture and transplantation experiments. Although crosslinking ESAM directly influenced gene transcription in HSCs, observations in conditional ESAM-knockout fetuses revealed the critical involvement of ESAM expressed in endothelial cells in fetal lethality. Thus, we showed that ESAM had important roles in developing definitive hematopoiesis. Furthermore, we unveiled the importance of endothelial ESAM in this process.

Excitatory amino acid transporter expression by astrocytes is neuroprotective against microglial excitotoxicity.

Glutamate-induced excitotoxicity is considered as a major cause of neurodegenerative disease. Excitatory amino acid transporters (EAATs) on glial cells are responsible for the homeostasis of extracellular glutamate in the central nervous system which may contribute to the prevention of excitotoxic neurodegeneration. However, the differential EAAT expression in astrocytes and microglia is not fully understood. In this study, we compared the expression of EAATs in astrocytes and microglia, and we assessed the neuroprotective and neurotoxic function of astrocytes and microglia by a co-culture system. RT-PCR analyses detected that astrocytes expressed each EAAT (EAAT1-5) whereas microglia did not express EAAT4. Western blot analyses demonstrated that astrocytes express a much larger amount of membrane-localized EAATs than microglia. Astrocytes prevented excito-neurotoxicity by the reduction of exogenous glutamate whereas microglia did not. Conversely, activated microglia released an excess of glutamate that induced excitotoxic neuronal death. Astrocytes rescued neurons from microglial glutamate-induced death in a ratio-dependent manner. Inhibition of EAATs abolished glutamate uptake and the neuroprotective effect of astrocytes, but it did not alter any microglial neurotoxic or neuroprotective effects. These results revealed that astrocytic EAATs can counteract microglial glutamate-induced neuronal death whereas microglial EAATs are inconsequential to neurotoxicity and neuroprotection.

Macrophage-induced neurotoxicity is mediated by glutamate and attenuated by glutaminase inhibitors and gap junction inhibitors.

We have shown previously, that the most neurotoxic factor from activated microglia is glutamate that is produced by glutaminase utilizing extracellular glutamine as a substrate. Drugs that inhibit glutaminase or gap junction through which the glutamate is released were effective in reducing neurotoxic activity of microglia. In this study, to elucidate whether or not a similar mechanism is operating in macrophages infiltrating into the central nervous system during inflammatory, demyelinating, and ischemic brain diseases, we examined the neurotoxicity induced by macrophages, in comparison with microglia in vitro. LPS- or TNF-alpha-stimulated macrophage-conditioned media induced robust neurotoxicity, which was completely inhibited by the NMDA receptor antagonist MK801. Both the glutaminase inhibitor 6-diazo-5-oxo-l-norleucine (DON), and the gap junction inhibitor carbenoxolone (CBX), effectively suppressed glutamate production and subsequent neurotoxicity by activated macrophages. These results revealed that macrophages produce glutamate via glutaminase from extracelluar glutamine, and release it through gap junctions. This study demonstrated that a similar machinery is operating in macrophages as well, and DON and CBX that prevent microglia-mediated neurotoxicity should be effective for preventing macrophage-mediated neurotoxicity. Thus, these drugs may be effective therapeutic reagents for inflammatory, demyelinating, and ischemic brain diseases.

Variable SATB1 Levels Regulate Hematopoietic Stem Cell Heterogeneity with Distinct Lineage Fate.

Hematopoietic stem cells (HSCs) comprise a heterogeneous population exhibiting self-renewal and differentiation capabilities; however, the mechanisms involved in maintaining this heterogeneity remain unclear. Here, we show that SATB1 is involved in regulating HSC heterogeneity. Results in conditional Satb1-knockout mice revealed that SATB1 was important for the self-renewal and lymphopoiesis of adult HSCs. Additionally, HSCs from Satb1/Tomato-knockin reporter mice were classified based on SATB1/Tomato intensity, with transplantation experiments revealing stronger differentiation toward the lymphocytic lineage along with high SATB1 levels, whereas SATB1- HSCs followed the myeloid lineage in agreement with genome-wide transcription and cell culture studies. Importantly, SATB1- and SATB1+ HSC populations were interconvertible upon transplantation, with SATB1+ HSCs showing higher reconstituting and lymphopoietic potentials in primary recipients relative to SATB1- HSCs, whereas both HSCs exhibited equally efficient reconstituted lympho-hematopoiesis in secondary recipients. These results suggest that SATB1 levels regulate the maintenance of HSC multipotency, with variations contributing to HSC heterogeneity.

Peroxisome proliferator-activated receptor gamma co-activator 1 gene Gly482Ser polymorphism is associated with the response of low-density lipoprotein cholesterol concentrations to exercise training in elderly Japanese.

Muscle peroxisome proliferator-activated receptor gamma co-activator 1 (PGC-1)α gene expression is influenced by the Gly482Ser gene polymorphism, which is a candidate genetic risk factor for diabetes mellitus and obesity. This study investigated the effects of PGC-1 gene Gly482Ser polymorphisms on alterations in glucose and lipid metabolism induced by exercise training. A 12-week intervention study was performed for 119 participants who were more than 65 years of age and completed exercise training at lactate threshold intensity. Total cholesterol and low-density lipoprotein cholesterol were significantly reduced in Gly/Gly but not in Gly/Ser and Ser/Ser participants after exercise. The Gly/Gly genotype of the PGC-1 gene Gly482Ser polymorphism influences the effects of moderate-intensity exercise training on low-density lipoprotein cholesterol and total cholesterol concentrations in older people.