GM-CSF Programs Hematopoietic Stem and Progenitor Cells During Candida albicans Vaccination for Protection Against Reinfection

More mechanistic studies are needed to reveal the hidden details of in vivo-induced trained immunity. Here, using a Candida albicans live vaccine mouse model we show that vaccination protects mice against a secondary infection and increases the number of bone marrow, and especially, splenic trained monocytes. Moreover, vaccination expands and reprograms hematopoietic stem and progenitor cells (HSPCs) early during infection and mobilize them transiently to the spleen to produce trained macrophages. Trained HSPCs are not only primed for myeloid cell production but also reprogramed to produce a greater amount of proinflammatory cytokines in response to a second challenge. Additionally, their adoptive transfer is sufficient to protect mice against reinfection. Mechanistically, autocrine GM-CSF activation of HSPCs is responsible for the trained phenotype and essential for the vaccine-induced protection. Our findings reveal a fundamental role for HSPCs in the trained immune protective response, opening new avenues for disease prevention and treatment.

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Dectin-1 Stimulation of Hematopoietic Stem and Progenitor Cells Occurs In Vivo and Promotes Differentiation Toward Trained Macrophages via an Indirect Cell-Autonomous Mechanism

mBio ◽

10.1128/mbio.00781-20 ◽

2020 ◽

Vol 11 (3) ◽

Cited By ~ 1

Author(s):

Cristina Bono ◽

Alba Martínez ◽

Javier Megías ◽

Daniel Gozalbo ◽

Alberto Yáñez ◽

...

Keyword(s):

Bone Marrow ◽

Candida Albicans ◽

Progenitor Cells ◽

Recipient Mouse ◽

Dependent Manner ◽

Toll Like Receptor ◽

Hematopoietic Stem ◽

Content Type ◽

Stem And Progenitor Cells

ABSTRACT Toll-like receptor (TLR) agonists drive hematopoietic stem and progenitor cells (HSPCs) to differentiate along the myeloid lineage. In this study, we used an HSPC transplantation model to investigate the possible direct interaction of β-glucan and its receptor (dectin-1) on HSPCs in vivo. Purified HSPCs from bone marrow of B6Ly5.1 mice (CD45.1 alloantigen) were transplanted into dectin-1−/− mice (CD45.2 alloantigen), which were then injected with β-glucan (depleted zymosan). As recipient mouse cells do not recognize the dectin-1 agonist injected, interference by soluble mediators secreted by recipient cells is negligible. Transplanted HSPCs differentiated into macrophages in response to depleted zymosan in the spleens and bone marrow of recipient mice. Functionally, macrophages derived from HSPCs exposed to depleted zymosan in vivo produced higher levels of inflammatory cytokines (tumor necrosis factor alpha [TNF-α] and interleukin 6 [IL-6]). These results demonstrate that trained immune responses, already described for monocytes and macrophages, also take place in HSPCs. Using a similar in vivo model of HSPC transplantation, we demonstrated that inactivated yeasts of Candida albicans induce differentiation of HSPCs through a dectin-1- and MyD88-dependent pathway. Soluble factors produced following exposure of HSPCs to dectin-1 agonists acted in a paracrine manner to induce myeloid differentiation and to influence the function of macrophages derived from dectin-1-unresponsive or β-glucan-unexposed HSPCs. Finally, we demonstrated that an in vitro transient exposure of HSPCs to live C. albicans cells, prior to differentiation, is sufficient to induce a trained phenotype of the macrophages they produce in a dectin-1- and Toll-like receptor 2 (TLR2)-dependent manner. IMPORTANCE Invasive candidiasis is an increasingly frequent cause of serious and often fatal infections. Understanding host defense is essential to design novel therapeutic strategies to boost immune protection against Candida albicans. In this article, we delve into two new concepts that have arisen over the last years: (i) the delivery of myelopoiesis-inducing signals by microbial components directly sensed by hematopoietic stem and progenitor cells (HSPCs) and (ii) the concept of “trained innate immunity” that may also apply to HSPCs. We demonstrate that dectin-1 ligation in vivo activates HSPCs and induces their differentiation to trained macrophages by a cell-autonomous indirect mechanism. This points to new mechanisms by which pathogen detection by HSPCs may modulate hematopoiesis in real time to generate myeloid cells better prepared to deal with the infection. Manipulation of this process may help to boost the innate immune response during candidiasis.

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Elevated Mcl-1 perturbs lymphopoiesis, promotes transformation of hematopoietic stem/progenitor cells, and enhances drug resistance

Blood ◽

10.1182/blood-2010-04-281071 ◽

2010 ◽

Vol 116 (17) ◽

pp. 3197-3207 ◽

Cited By ~ 80

Author(s):

Kirsteen J. Campbell ◽

Mary L. Bath ◽

Marian L. Turner ◽

Cassandra J. Vandenberg ◽

Philippe Bouillet ◽

...

Keyword(s):

Progenitor Cells ◽

Progenitor Cell ◽

Fetal Liver ◽

Cytotoxic Agents ◽

Hematopoietic Stem ◽

Stem And Progenitor Cells ◽

Fetal Liver Cells ◽

Follicular Lymphomas ◽

The Impact

Abstract Diverse human cancers with poor prognosis, including many lymphoid and myeloid malignancies, exhibit high levels of Mcl-1. To explore the impact of Mcl-1 overexpression on the hematopoietic compartment, we have generated vavP-Mcl-1 transgenic mice. Their lymphoid and myeloid cells displayed increased resistance to a variety of cytotoxic agents. Myelopoiesis was relatively normal, but lymphopoiesis was clearly perturbed, with excess mature B and T cells accumulating. Rather than the follicular lymphomas typical of vavP-BCL-2 mice, aging vavP-Mcl-1 mice were primarily susceptible to lymphomas having the phenotype of a stem/progenitor cell (11 of 30 tumors) or pre-B cell (12 of 30 tumors). Mcl-1 overexpression dramatically accelerated Myc-driven lymphomagenesis. Most vavP-Mcl-1/ Eμ-Myc mice died around birth, and transplantation of blood from bitransgenic E18 embryos into unirradiated mice resulted in stem/progenitor cell tumors. Furthermore, lethally irradiated mice transplanted with E13 fetal liver cells from Mcl-1/Myc bitransgenic mice uniformly died of stem/progenitor cell tumors. When treated in vivo with cyclophosphamide, tumors coexpressing Mcl-1 and Myc transgenes were significantly more resistant than conventional Eμ-Myc lymphomas. Collectively, these results demonstrate that Mcl-1 overexpression renders hematopoietic cells refractory to many cytotoxic insults, perturbs lymphopoiesis and promotes malignant transformation of hematopoietic stem and progenitor cells.

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Hematopoietic stem and progenitor cells are present in healthy gingiva tissue

Journal of Experimental Medicine ◽

10.1084/jem.20200737 ◽

2021 ◽

Vol 218 (4) ◽

Author(s):

Siddharth Krishnan ◽

Kelly Wemyss ◽

Ian E. Prise ◽

Flora A. McClure ◽

Conor O’Boyle ◽

...

Keyword(s):

Bone Marrow ◽

Immune Responses ◽

Progenitor Cells ◽

Myeloid Cell ◽

Extramedullary Hematopoiesis ◽

Innate Immune ◽

Innate Immune Cells ◽

Hematopoietic Stem ◽

Effector Cells ◽

Stem And Progenitor Cells

Hematopoietic stem cells reside in the bone marrow, where they generate the effector cells that drive immune responses. However, in response to inflammation, some hematopoietic stem and progenitor cells (HSPCs) are recruited to tissue sites and undergo extramedullary hematopoiesis. Contrasting with this paradigm, here we show residence and differentiation of HSPCs in healthy gingiva, a key oral barrier in the absence of overt inflammation. We initially defined a population of gingiva monocytes that could be locally maintained; we subsequently identified not only monocyte progenitors but also diverse HSPCs within the gingiva that could give rise to multiple myeloid lineages. Gingiva HSPCs possessed similar differentiation potentials, reconstitution capabilities, and heterogeneity to bone marrow HSPCs. However, gingival HSPCs responded differently to inflammatory insults, responding to oral but not systemic inflammation. Combined, we highlight a novel pathway of myeloid cell development at a healthy barrier, defining a gingiva-specific HSPC network that supports generation of a proportion of the innate immune cells that police this barrier.

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Single-Cell RNA Sequencing of Hematopoietic Stem and Progenitor Cells Treated with Gemcitabine and Carboplatin

Genes ◽

10.3390/genes11050549 ◽

2020 ◽

Vol 11 (5) ◽

pp. 549

Author(s):

Niclas Björn ◽

Ingrid Jakobsen ◽

Kourosh Lotfi ◽

Henrik Gréen

Keyword(s):

Cell Cycle ◽

Cell Proliferation ◽

Single Cell ◽

Progenitor Cells ◽

Myeloid Cell ◽

Enrichment Analysis ◽

Myelogenous Leukemia ◽

Transcriptional Level ◽

Hematopoietic Stem ◽

Stem And Progenitor Cells

Treatments that include gemcitabine and carboplatin induce dose-limiting myelosuppression. The understanding of how human bone marrow is affected on a transcriptional level leading to the development of myelosuppression is required for the implementation of personalized treatments in the future. In this study, we treated human hematopoietic stem and progenitor cells (HSPCs) harvested from a patient with chronic myelogenous leukemia (CML) with gemcitabine/carboplatin. Thereafter, scRNA-seq was performed to distinguish transcriptional effects induced by gemcitabine/carboplatin. Gene expression was calculated and evaluated among cells within and between samples compared to untreated cells. Cell cycle analysis showed that the treatments effectively decrease cell proliferation, indicated by the proportion of cells in the G2M-phase dropping from 35% in untreated cells to 14.3% in treated cells. Clustering and t-SNE showed that cells within samples and between treated and untreated samples were affected differently. Enrichment analysis of differentially expressed genes showed that the treatments influence KEGG pathways and Gene Ontologies related to myeloid cell proliferation/differentiation, immune response, cancer, and the cell cycle. The present study shows the feasibility of using scRNA-seq and chemotherapy-treated HSPCs to find genes, pathways, and biological processes affected among and between treated and untreated cells. This indicates the possible gains of using single-cell toxicity studies for personalized medicine.

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Hematopoietic progenitors in cyclic neutropenia: effect of granulocyte colony-stimulating factor in vivo

Blood ◽

10.1182/blood.v75.10.1951.1951 ◽

1990 ◽

Vol 75 (10) ◽

pp. 1951-1959 ◽

Cited By ~ 39

Author(s):

AR Migliaccio ◽

G Migliaccio ◽

DC Dale ◽

WP Hammond

Keyword(s):

Growth Factor ◽

Progenitor Cells ◽

Blood Cells ◽

Granulocyte Colony Stimulating Factor ◽

Colony Stimulating Factor ◽

Cyclic Neutropenia ◽

Hematopoietic Stem ◽

Gm Csf ◽

Stimulating Factor

Abstract The number and growth factor requirements of committed progenitor cells (colony-forming units-granulocyte/macrophage and burst-forming units- erythroid) in three patients with cyclic neutropenia (two congenital, one acquired) were studied before and during therapy with recombinant human granulocyte colony-stimulating factor (G-CSF; 3 to 10 micrograms/kg/d). When the patients with congenital disease were treated with G-CSF, the cycling of blood cells persisted, but the cycle length was shortened from 21 days to 14 days, and the amplitude of variations in blood counts increased. There was a parallel shortening of the cycle and increase of the amplitude of variations (from two- to three-fold to 10- to 100-fold) in the number of both types of circulating progenitor cells in these two patients. In the patient with acquired cyclic neutropenia, cycling of both blood cells and progenitors could not be seen. In cultures deprived of fetal bovine serum, erythroid and myeloid bone marrow progenitor cells from untreated patients and from normals differed in growth factor responsiveness. As examples, maximal growth of granulocyte/macrophage (GM) colonies was induced by granulocyte/macrophage (GM)-CSF plus G-CSF in the patients, whereas a combination of GM-CSF, G-CSF and interleukin- 3 (IL-3) was required in the normals, and erythropoietin alone induced fourfold more erythroid bursts from cyclic neutropenic patients than from normal donors (46% versus 11% of the maximal colony number, respectively). The growth factor responsiveness of marrow progenitor cells slightly changed during the treatment toward the values observed with normal progenitors. These results indicate that treatment with G- CSF not only ameliorated the neutropenia, but also increased the amplitude and the frequency of oscillation of circulating progenitor cell numbers. These data are consistent with the hypothesis that G-CSF therapy affects the proliferation of the hematopoietic stem cell.

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Involvement of p21cip-1 and p27kip-1 in the molecular mechanisms of steel factor-induced proliferative synergy in vitro and of p21cip-1 in the maintenance of stem/progenitor cells in vivo

Blood ◽

10.1182/blood.v88.10.3710.bloodjournal88103710 ◽

1996 ◽

Vol 88 (10) ◽

pp. 3710-3719 ◽

Cited By ~ 82

Author(s):

C Mantel ◽

Z Luo ◽

J Canfield ◽

S Braun ◽

C Deng ◽

...

Keyword(s):

Progenitor Cells ◽

Proliferative Response ◽

Myeloid Cell ◽

Cyclin Dependent Kinase ◽

Hematopoietic Progenitor ◽

Gm Csf ◽

Myeloid Progenitor ◽

Myeloid Progenitor Cells

Steel factor (SLF) is a hematopoietic cytokine that synergizes with other growth factors to induce a greatly enhanced proliferative state of hematopoietic progenitor cells and factor-dependent cell lines. Even though the in vivo importance of SLF in the maintenance and responsiveness of stem and progenitor cells is well documented, the molecular mechanism involved in its synergistic effects are mainly unknown. Some factor-dependent myeloid cell lines respond to the synergistic proliferative effects of SLF plus other cytokines in a manner similar to that of normal myeloid progenitor cells from bone marrow and cord blood. We show here that SLF can synergize with granulocyte-macrophage colony-stimulating factor (GM-CSF) to induce an enhanced phosphorylation of the retinoblastoma gene product and a synergistic increase in the total intracellular protein level of the cyclin-dependent kinase inhibitor, p21cip-1, which is correlated with a simultaneous decrease in p27kip-1 in the human factor-dependent myeloid cell line, M07e. Moreover, these cytokines synergize to increase p21cip- 1 binding and decrease p27kip-1 binding to cyclin-dependent kinase-2 (cdk2), an enzyme required for normal cell cycle progression; these inverse events correlated with increased cdk2 kinase activity. It is also shown that exogenous purified p21cip-1 can displace p27kip-1 already bound to cdk2 in vitro. These data implicate increased p21cip-1 and decreased p27kip-1 intracellular concentrations and their stoichiometric interplay in the enhanced proliferative status of cells stimulated by the combination of SLF and GM-CSF. In support of these findings, it is shown that hematopoietic progenitor cells from mice lacking p21cip-1 are defective in SLF synergistic proliferative response in vitro. Moreover, the cycling status of marrow and spleen progenitors and absolute numbers of marrow progenitors were significantly decreased in the p21cip-1 -/-, compared with the +/+ mice. We conclude that the cdk threshold regulators p21cip-1 and p27kip- 1 play a critical role in the normal mitogenic response of M07e cells and murine myeloid progenitor cells to these cytokines and particularly in the SLF synergistic proliferative response that is important to the normal maintenance of the stem/progenitor cell compartment.

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IN VIVO EFFECTS OF ELTROMBOPAG ON THE EXPANSION OF HEMATOPOIETIC STEM AND PROGENITOR CELLS IN APLASTIC ANAEMIA

Hematology Transfusion and Cell Therapy ◽

10.1016/j.htct.2020.10.014 ◽

2020 ◽

Vol 42 ◽

pp. 8-9

Author(s):

B.Q. Oliveira ◽

B.A.A.S. Lemos ◽

L.F.B. Catto ◽

M.F. Tellechea ◽

P. Scheinberg ◽

...

Keyword(s):

Progenitor Cells ◽

Aplastic Anaemia ◽

Hematopoietic Stem ◽

Stem And Progenitor Cells ◽

In Vivo Effects

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Involvement of the Integrin Alpha 6 Receptor in the Homing and Engraftment of Hematopoietic Stem and Progenitor Cells to Bone Marrow.

Blood ◽

10.1182/blood.v104.11.1293.1293 ◽

2004 ◽

Vol 104 (11) ◽

pp. 1293-1293

Author(s):

Hong Qian ◽

Sten Eirik W. Jacobsen ◽

Marja Ekblom

Keyword(s):

Bone Marrow ◽

Stem Cell ◽

Progenitor Cells ◽

Progenitor Cell ◽

Bone Marrow Cells ◽

Hematopoietic Stem ◽

Stem And Progenitor Cells ◽

Functional Blocking

Abstract Within the bone marrow environment, adhesive interactions between stromal cells and extracellular matrix molecules are required for stem and progenitor cell survival, proliferation and differentiation as well as their transmigration between bone marrow (BM) and the circulation. This regulation is mediated by cell surface adhesion receptors. In experimental mouse stem cell transplantation models, several classes of cell adhesion receptors have been shown to be involved in the homing and engraftment of stem and progenitor cells in BM. We have previously found that integrin a6 mediates human hematopoietic stem and progenitor cell adhesion to and migration on its specific ligands, laminin-8 and laminin-10/11 in vitro (Gu et al, Blood, 2003; 101:877). Using FACS analysis, the integrin a6 chain was now found to be ubiquitously (>95%) expressed in mouse hematopoietic stem and progenitor cells (lin−Sca-1+c-Kit+, lin−Sca-1+c-Kit+CD34+) both in adult bone marrow and in fetal liver. In vitro, about 70% of mouse BM lin−Sca-1+c-Kit+ cells adhered to laminin-10/11 and 40% adhered to laminin-8. This adhesion was mediated by integrin a6b1 receptor, as shown by functional blocking monoclonal antibodies. We also used a functional blocking monoclonal antibody (GoH3) against integrin a6 to analyse the role of the integrin a6 receptor for the in vivo homing of hematopoietic stem and progenitor cells. We found that the integrin a6 antibody inhibited the homing of bone marrow progenitors (CFU-C) into BM of lethally irradiated recipients. The number of homed CFU-C was reduced by about 40% as compared to cells incubated with an isotype matched control antibody. To study homing of long-term repopulating stem cells (LTR), antibody treated bone marrow cells were first injected intravenously into lethally irradiated primary recipients. After three hours, bone marrow cells of the primary recipients were analysed by competitive repopulation assay in secondary recipients. Blood analysis 16 weeks after transplantation revealed an 80% reduction of stem cell activity of integrin a6 antibody treated cells as compared to cells treated with control antibody. These results suggest that integrin a6 plays an important role for hematopoietic stem and progenitor cell homing in vivo.

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Integrin alpha 6 Is Essential for Fetal Hematopoietic Progenitor, but Not Fetal Stem Cell Homing to Bone Marrow.

Blood ◽

10.1182/blood.v106.11.1387.1387 ◽

2005 ◽

Vol 106 (11) ◽

pp. 1387-1387

Author(s):

Hong Qian ◽

Sten Eirik W. Jacobsen ◽

Marja Ekblom

Keyword(s):

Bone Marrow ◽

Stem Cell ◽

Progenitor Cells ◽

Progenitor Cell ◽

Fetal Liver ◽

Hematopoietic Stem ◽

Stem And Progenitor Cells ◽

Integrin Alpha 6

Abstract Homing of transplanted hematopoietic stem cells (HSC) in the bone marrow (BM) is a prerequisite for establishment of hematopoiesis following transplantation. However, although multiple adhesive interactions of HSCs with BM microenviroment are thought to critically influence their homing and subsequently their engraftment, the molecular pathways that control the homing of transplanted HSCs, in particular, of fetal HSCs are still not well understood. In experimental mouse stem cell transplantation models, several integrins have been shown to be involved in the homing and engraftment of both adult and fetal stem and progenitor cells in BM. We have previously found that integrin a6 mediates human hematopoietic stem and progenitor cell adhesion to and migration on its specific ligands, laminin-8 and laminin-10/11 in vitro (Gu et al, Blood, 2003; 101:877). Furthermore, integrin a6 is required for adult mouse HSC homing to BM in vivo (Qian et al., Abstract American Society of Hematology, Blood 2004 ). We have now found that the integrin a6 chain like in adult HSC is ubiquitously (>99%) expressed also in fetal liver hematopoietic stem and progenitor cells (lin−Sca-1+c-Kit+, LSK ). In vitro, fetal liver LSK cells adhere to laminin-10/11 and laminin-8 in an integrin a6b1 receptor-dependent manner, as shown by function blocking monoclonal antibodies. We have now used a function blocking monoclonal antibody (GoH3) against integrin a6 to analyse the role of the integrin a6 receptor for the in vivo homing of fetal liver hematopoietic stem and progenitor cells to BM. The integrin a6 antibody inhibited homing of fetal liver progenitors (CFU-C) into BM of lethally irradiated recipients. The number of homed CFU-C in BM was reduced by about 40% as compared to the cells incubated with an isotype matched control antibody. To study homing of long-term repopulating stem cells, BM cells were first incubated with anti-integrin alpha 6 or anti-integrin alpha 4 or control antibody, and then injected intravenously into lethally irradiated primary recipients. After three hours, BM cells of the primary recipients were analysed by competitive repopulation assay in secondary recipients. Blood analysis up to 16 weeks after transplantation showed that no reduction of stem cell reconstitution from integrin a6 antibody treated cells as compared to cells treated with control antibody. In accordance with this, fetal liver HSC from integrin a6 gene deleted embryos did not show any impairment of homing and engraftment in BM as compared to normal littermates. These results suggest that integrin a6 plays an important developmentally regulated role for homing of distinct hematopoietic stem and progenitor cell populations in vivo.

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Enforced Expression of GATA-2 Confers Quiescence on Human Hematopoietic Stem and Progenitor Cells In Vitro and In Vivo.

Blood ◽

10.1182/blood.v108.11.83.83 ◽

2006 ◽

Vol 108 (11) ◽

pp. 83-83

Author(s):

Alex J. Tipping ◽

Cristina Pina ◽

Anders Castor ◽

Ann Atzberger ◽

Dengli Hong ◽

...

Keyword(s):

Cell Cycle ◽

Progenitor Cells ◽

Zinc Finger ◽

Human Cord Blood ◽

Hematopoietic Stem ◽

Cd34 Cells ◽

Stem And Progenitor Cells ◽

Colony Number

Abstract Hematopoietic stem cells (HSCs) in adults are largely quiescent, periodically entering and exiting cell cycle to replenish the progenitor pool or to self-renew, without exhausting their number. Expression profiling of quiescent HSCs in our and other laboratories suggests that high expression of the zinc finger transcription factor GATA-2 correlates with quiescence. We show here that TGFβ1-induced quiescence of wild-type human cord blood CD34+ cells in vitro correlated with induction of endogenous GATA-2 expression. To directly test if GATA-2 has a causative role in HSC quiescence we constitutively expressed GATA-2 in human cord blood stem and progenitor cells using lentiviral vectors, and assessed the functional output from these cells. In both CD34+ and CD34+ CD38− populations, enforced GATA-2 expression conferred increased quiescence as assessed by Hoechst/Pyronin Y staining. CD34+ cells with enforced GATA-2 expression showed reductions in both colony number and size when assessed in multipotential CFC assays. In CFC assays conducted with more primitive CD34+ CD38− cells, colony number and size were also reduced, with myeloid and mixed colony number more reduced than erythroid colonies. Reduced CFC activity was not due to increased apoptosis, as judged by Annexin V staining of GATA-2-transduced CD34+ or CD34+ CD38− cells. To the contrary, in vitro cultures from GATA-2-transduced CD34+ CD38− cells showed increased protection from apoptosis. In vitro, proliferation of CD34+ CD38− cells was severely impaired by constitutive expression of GATA-2. Real-time PCR analysis showed no upregulation of classic cell cycle inhibitors such as p21, p57 or p16INK4A. However GATA-2 expression did cause repression of cyclin D3, EGR2, E2F4, ANGPT1 and C/EBPα. In stem cell assays, CD34+ CD38− cells constitutively expressing GATA-2 showed little or no LTC-IC activity. In xenografted NOD/SCID mice, transduced CD34+ CD38−cells expressing high levels of GATA-2 did not contribute to hematopoiesis, although cells expressing lower levels of GATA-2 did. This threshold effect is presumably due to DNA binding by GATA-2, as a zinc-finger deletion variant of GATA-2 shows contribution to hematopoiesis from cells irrespective of expression level. These NOD/SCID data suggest that levels of GATA-2 may play a part in the in vivo control of stem and progenitor cell proliferation. Taken together, our data demonstrate that GATA-2 enforces a transcriptional program on stem and progenitor cells which suppresses their responses to proliferative stimuli with the result that they remain quiescent in vitro and in vivo.

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