scholarly journals Long Term Culture of Primary AML and CML Cells: Effects of Growth Factor Composition on Cell Expansion and Differentiation

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 5097-5097
Author(s):  
Ondrej Venglár ◽  
Martin Culen ◽  
Jana Cerna ◽  
Zdenka Kosarova ◽  
Jiri Mayer ◽  
...  
Keyword(s):  
Research Funding ◽  
De Novo ◽  
Relative Yield ◽  
Culture Conditions ◽  
Negative Control ◽  
Long Term Culture ◽  
Cd34 Cells ◽  
Supporting Condition

Abstract Introduction: In vitro experiments with primary acute and chronic myeloid leukemia (AML, CML) cells are widely applied for testing of anti-tumor drug activity. Several studies also documented long-term maintenance of primary cells with the support of stromal cells and growth factors. However, to our knowledge, none of these studies sufficiently analyzed the differentiation and phenotype changes occurring during the long-term culture. Aim: To evaluate the expansion and phenotype changes of primary AML and CML cells in long-term culture using different cytokine cocktails. Methods: Primary leukocytes from 6 de novo AML samples, 5×10^5 per well, (various French-American-British classification) and CD34+ cells isolated from 4 de novo CML samples, 15-50×10^3 per well, were seeded onto a confluent layer of human bone-marrow mesenchymal stromal cells (MSCs) in 24-well plates. Four culture conditions were tested: a) "stem cell" supporting condition, designated as C4, with 4 early acting cytokines SCF, TPO, FLT3-ligand and IL-6, b) myeloid cell supporting condition C6, with the C4 cytokines plus two additional late acting growth factors IL-1 and IL-3, c) myeloid cell supporting condition C7 with the same cytokines as C6 plus terminal differentiation factor GM-CSF, d) condition adopted from previous studies, designated as C3, containing cytokines TPO, IL-3, G-SCF. Additional negative control condition C-neg did not include MSCs nor any cytokines. Experiments were analyzed after 2-weeks of culture. Phenotypization was performed both pre- and post-culture by flow cytometry. Results: For all AML samples, the tested culture conditions showed successful maintenance of cells in vitro, although with highly heterogeneous expansion rates for the individual samples (0-14 fold expansion, yielding up to 3.5×10^6 cells per well). No AML cells survived in the negative control condition C-neg, for 4/6 samples. The maximum expansion (representing relative yield of 100%) was obtained with the myelo-condition C7 in 5/6 patients. The mean relative yield from all patients for C7 was 97%. The other conditions provided mean relative yields of: C6 - 79%, C4 - 43%, C3 - 44%, and C-neg - 3.5%. Comparison of pre- and post-culture phenotypes revealed differentiation of AML cells in vitro, demonstrated by the decrease of primitive CD34+ fraction and shifting of less differentiated CD33dim cells into mature CD33bright fraction (mean log2 reduction in CD34+ cells: C4 - 0.5×, p=0.4, C7 - 1.4×, p=0.01, C6 - 1.3×, p=0.01, C3 - 1.0×, p=0.03; mean log2 reduction in CD33dim cells: C4 - 0.8×, p=0.2, C7 - 2.0×, p<0.001, C6 - 2.0×, p<0.001, C3 - 1.1×, p=0.07). Expression of CD14 and also CD117 showed large intra-patient differences (both increase and decrease), without statistically significant differences between the culture conditions. CD123 expression remained stable. The CML samples were cultured only with C4, C6, C3 conditions, without the terminal differentiation C7 condition. Expansion reached 33-260 fold; yielding up to 3.3×10^6 cells per well. C3 condition provided the highest yields (mean relative yields: C4 - 29%, C6 - 68%, C3 - 93%, and C-neg - 0%). All three tested conditions produced dominant fraction of more mature myeloid CD33+ cells (mean, 86-94%). Nevertheless, the C4 condition provided the highest proportion of CD34+ cells and produced the least mature CD14+ monocytes, compared to C6 and C3 (mean, CD34+ cell fraction of leukocytes: C4 - 31.7%, C6 - 6.8%, C3 - 4.5%; mean, CD14+ cell fraction of leukocytes: C4 - 6%, C6 - 21%, C3 - 9.6%). Conclusions: All tested culture conditions were capable of maintaining both primary AML and CML cells from all samples, during the 2-week culture. The highest in vitro expansion was achieved with conditions using the late-acting cytokines which however induced the highest cell differentiation as well. The C3 condition reported in previous studies also provided insufficient conservation of the original phenotypes. In this setup, the best preservation of original phenotypes and more primitive cells was achieved using the C4 "stem cell" condition containing early acting cytokines. Supported by Ministry of Health of the Czech Republic, grant nr. 17-30397A. All rights reserved. This report was written with the support of the Specific University Research (nr. MUNI/A/0968/2017) provided by MEYS. Disclosures Mayer: Affimed: Research Funding; Eisai: Research Funding; Johnson & Johnson: Research Funding; Roche: Research Funding; Novartis: Research Funding.

scholarly journals Loss of primitive hematopoietic progenitors in patients with human immunodeficiency virus infection

Blood ◽  
1996 ◽  
Vol 88 (12) ◽  
pp. 4568-4578 ◽  
Author(s):  
A Marandin ◽  
A Katz ◽  
E Oksenhendler ◽  
M Tulliez ◽  
F Picard ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Human Immunodeficiency Virus ◽  
Long Term Culture ◽  
Cd34 Cells ◽  
Immunodeficiency Virus ◽  
Cell Fractions ◽  
Cd38 Antigen ◽  
Hiv 1

A number of hematologic abnormalities, including cytopenias, have been observed in patients with human immunodeficiency virus (HIV) infection. To elucidate their mechanisms, primitive cells from bone marrow aspirates of 21 patients with HIV-1 infection were quantitated by flow cytometry. The mean percentage of CD34+ cells is not significantly altered in HIV-1-infected patients in comparison with HIV-1- seronegative controls. In contrast, two- and three-color immunofluorescence analysis showed that in all HIV-1 samples, most CD34+ cells coexpressed the CD38 antigen. The proportion of HIV-1- derived CD34+ cells that did not express the CD38 antigen was significantly lower (HIV-1+: mean, 1.73%; controls: mean, 14%; P < .0005) than in controls. Moreover, of Thy-1+ cells, the proportion of CD34+ cells was twofold lower in HIV-1-infected patients (HIV-1+: mean, 12%; controls, 25%, P < .0005), which suggests that phenotypically primitive cells are depleted in HIV-1 infection. In vitro functional analysis in long-term cultures of sorted CD34+ cells from seven HIV-1 patients showed that CD34+ cells from HIV-1 patients generated much fewer colonies both in the nonadherent and adherent layers than CD34+ cells from controls after 5 weeks of culture (10-fold and four-fold less, respectively). Precise long-term culture initiating cell (LTC-IC) frequency in the CD34+ cell population was determined in three patients by limiting dilution and was markedly decreased in comparison to that of normal controls (from twofold to > sevenfold decreased). To determine if primitive cells were infected by HIV-1, both methylcellulose colonies generated from long-term culture of CD34+ cells and various CD34+ cell fractions purified by flow cytometry were evaluated for the presence of HIV-1 by polymerase chain reaction (PCR). Progeny from long-term culture was HIV-1-negative in three samples. In addition, using a sensitive PCR technique, the HIV-1 genome could not be detected in CD34+, CD34+/CD38-, and CD34+/CD4+ cells. These data show that hematologic disorders in HIV disease may be the consequence of a deficit of primitive cells. However, direct infection of these cells by HIV-1 does not seem to be responsible for this defect.

HUMAN ENDOTHELIAL CELLS MODIFICATIONS DURING LONG TERM CULTURE

1987 ◽  
Author(s):  
M P Wautier ◽  
J L Wautier
Keyword(s):  
Endothelial Cells ◽  
Doubling Time ◽  
Umbilical Vein ◽  
Light And Electron Microscopy ◽  
Major Change ◽  
Culture Conditions ◽  
Human Endothelial Cells ◽  
Long Term Culture

The culture of human endothelial cells is largely used for vascular research. The possibility of developping long term culture of human endothelial cells (EC) raised the question regarding the identity after several passages. To further investigate this aspect we have cultured human umbilical vein EC until the 12th passage on fibronectin coated dishes supplemented with ECGF. We have studied the EC morphology by light and electron microscopy, the reactivity with 51Cr labelled platelets, and prostacyclin synthesis. Until the 6th passage no major change could be noted, except the occurence of rare large EC and a reduction in the doubling time between 2nd and 5th passage. After the 7th passage up to the 10th EC became more elongated and did not grow in strict monolayer. The number of vacuoles and mitochondria increased as well as the doubling time. After the 12th passage the EC were still viable but proliferated very slowly. The adhesion of radiolabelled platelets dramatically increased (150%) and PGI2 production significantly decreased (6 Keto PGF1α : 1st passage 13±2.5 ng; 6th passage 0.33±0.27 ng/106 EC). In our culture conditions EC kept most of their original characteristics up to the 6th passage but then lost some of them. At any passage EC contained Weibel Palade bodies and von Willebrand factor. We can conclude that after the 7th passage EC in culture are different from the original cells and could possibly represent an in vitro model of EC ageing.

scholarly journals Activation of the receptor tyrosine kinase RET improves long-term hematopoietic stem cell outgrowth and potency

Blood ◽  
2020 ◽  
Vol 136 (22) ◽  
pp. 2535-2547 ◽  
Author(s):  
W. Grey ◽  
R. Chauhan ◽  
M. Piganeau ◽  
H. Huerga Encabo ◽  
M. Garcia-Albornoz ◽  
...  
Keyword(s):  
Intracellular Signaling ◽  
Culture Conditions ◽  
Cellular Growth ◽  
Great Promise ◽  
Bone Marrow Niche ◽  
Hematopoietic Stem ◽  
Intracellular Signaling Pathway ◽  
Wide Range

Abstract Expansion of human hematopoietic stem cells (HSCs) is a rapidly advancing field showing great promise for clinical applications. Recent evidence has implicated the nervous system and glial family ligands (GFLs) as potential drivers of hematopoietic survival and self-renewal in the bone marrow niche; how to apply this process to HSC maintenance and expansion has yet to be explored. We show a role for the GFL receptor, RET, at the cell surface of HSCs in mediating sustained cellular growth, resistance to stress, and improved cell survival throughout in vitro expansion. HSCs treated with the key RET ligand/coreceptor complex, glial-derived neurotrophic factor and its coreceptor, exhibit improved progenitor function at primary transplantation and improved long-term HSC function at secondary transplantation. Finally, we show that RET drives a multifaceted intracellular signaling pathway, including key signaling intermediates protein kinase B, extracellular signal-regulated kinase 1/2, NF-κB, and p53, responsible for a wide range of cellular and genetic responses that improve cell growth and survival under culture conditions.

Structure of vegetative organs in essential oil rose under standard culture conditions and long-term conservation in vitro

2021 ◽  
pp. 185-190
Author(s):  
I.V. Mitrofanova ◽  
V.A. Brailko ◽  
N.P. Lesnikova-Sedoshenko ◽  
N.N. Ivanova ◽  
O.V. Mitrofanova
Keyword(s):  
Essential Oil ◽  
Culture Conditions ◽  
Vegetative Organs ◽  
Standard Culture

scholarly journals Long-Term Experience with Large Granular Lymphocytic Leukemia Evolving after Solid Organ and Hematopoietic Stem Cell Transplantation

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 1226-1226
Author(s):  
Hassan Awada ◽  
Reda Z. Mahfouz ◽  
Jibran Durrani ◽  
Ashwin Kishtagari ◽  
Deepa Jagadeesh ◽  
...  
Keyword(s):  
Board Of Directors ◽  
Research Funding ◽  
Viral Infections ◽  
De Novo ◽  
Post Transplantation ◽  
Advisory Committees ◽  
Hematopoietic Stem ◽  
Post Transplant ◽  
Stat3 Mutations

T-cell large granular lymphocyte leukemia (T-LGLL) is a clonal proliferation of cytotoxic T lymphocytes (CTL). T-LGLL mainly manifest in elderly and is associated with autoimmune diseases including rheumatoid arthritis (RA), B cell dyscrasias, non-hematologic cancers and immunodeficiency (e.g., hypogammaglobulinemia). LGL manifestations often resemble reactive immune processes leading to the dilemmas that LGLs act like CTL expansion during viral infections (for example EBV associated infectious mononucleosis). While studying a cohort of 246 adult patients with T-LGLL seen at Cleveland Clinic over the past 10 years, we encountered 15 cases of overt T-LGLL following transplantation of solid organs (SOT; n=8) and hematopoietic stem cell transplantation (HSCT; n=7). Although early studies reported on the occurrence of LGL post-transplant, these studies focused on the analysis of oligoclonality skewed reactive CTL responses rather than frank T-LGLL. We aimed to characterize post-transplantation T-LGLL in SOT and HSCT simultaneously and compare them to a control group of 231 de novo T-LGLL (cases with no history of SOT or HSCT). To characterize an unambiguous "WHO-defined T-LGLL" we applied stringent and uniform criteria. All cases were diagnosed if 3 out of 4 criteria were fulfilled, including: 1) LGL count >500/µL in blood for more than 6 months; 2) abnormal CTLs expressing CD3, CD8 and CD57 by flow cytometry; 3) preferential usage of a TCR Vβ family by flow cytometry; 4) TCR gene rearrangement by PCR. In addition, targeted deep sequencing for STAT3 mutations was performed and charts of bone marrow biopsies were reviewed to exclude other possible conditions. Diagnosis was made 0.2-27 yrs post-transplantation (median: 4 yrs). At the time of T-LGLL diagnosis, relative lymphocytosis (15-91%), T lymphocytosis (49-99%) and elevated absolute LGL counts (>500 /µL; 93%) were also seen. Post-transplantation T-LGLL were significantly younger than de novo T-LGLL, (median age: 48 vs. 61 yr; P<.0001). Sixty% of post-transplantation T-LGLL patients were males. Fifteen% of patients had more cytogenetic abnormalities compared to de novo T-LGLL, had a lower absolute LGL count (median: 4.5 vs. 8.5 k/µL) and had less frequent neutropenia, thrombocytopenia and anemia (27 vs. 43%, 33 vs. 35% and 20% vs. 55%; P=.01). TCR Vb analysis identified clonal expansion of ≥1 of the Vb proteins in 60% (n=9) of the patients; the remaining 40% (n=6) of the cases had either a clonal process involving a Vb protein not tested in the panel (20%; n=3) or no clear expansion (20%; n=3). Signs of rejection were observed in 20% (n=3/15) and GvHD in 13% (n=2/15) of the patients. Post-transplantation, 27% of cases presented with neutropenia (absolute neutrophil count <1.5 x109/L; n=4), 33% with thrombocytopenia (platelet count <150 x109/L; n=5) and 25% with anemia (hemoglobin <10 g/dL; n=3). T-LGLL evolved in 10 patients (67%; 10/15) despite IST including cyclosporine (n=5), tacrolimus (n=4), mycophenolate mofetil (n=5), cyclophosphamide (n=1), anti-thymocyte globulin (n=1), and corticosteroids (n=6). Lymphadenopathy and splenomegaly were seen in 13% (n=2) and 33% (n=5) of the patients. Other conditions observed were MGUS (20%; n=3) and RA (7%; n=1). Conventional cytogenetic showed normal karyotype in 89% (n=11, tested individuals 13/15). Somatic STAT3 mutations were identified in 2 patients. Sixty% of cases (n=9) were seropositive for EBV when tested at different time points after transplant. Similarly, 53% (n=8) were seropositive for CMV, of which, 5 were positive post-transplantation and 3 pre-/post-transplantation. The complexity of T-LGLL expansion post-transplantation might be due to several mechanisms including active viral infections, latent oncogenic viral reactivation and graft allo-antigenic stimulation. However, in our cohort graft rejection or GvHD was encountered in a few patients (2 allo-HSCT recipients). Autoimmune conditions were present in 50% of SOT recipients (n=4/ 8, including RA, ulcerative colitis, systemic lupus erythematosus). Some of our patients also had low immunoglobulin levels. Overt EBV (post-transplant lymphoproliferative disorder) and CMV reactivation was diagnosed in only 27% (4/15) of the patients. In sum we report the long term follow up of a cohort of T-LGLL and emphasize the expansion of T-LGLL post-transplant highlighting the difficulty in assigning one unique origin of LGLL. Disclosures Hill: Genentech: Consultancy, Research Funding; Takeda: Research Funding; Celegene: Consultancy, Honoraria, Research Funding; Kite: Consultancy, Honoraria; Abbvie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Seattle Genetics: Consultancy, Honoraria; Amgen: Research Funding; Pharmacyclics: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Gilead: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; TG therapeutics: Research Funding; AstraZeneca: Consultancy, Honoraria. Majhail:Atara Bio: Consultancy; Mallinckrodt: Honoraria; Nkarta: Consultancy; Anthem, Inc.: Consultancy; Incyte: Consultancy. Sekeres:Syros: Membership on an entity's Board of Directors or advisory committees; Millenium: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees. Maciejewski:Alexion: Consultancy; Novartis: Consultancy.

scholarly journals Cycle initiation and colony formation in culture by murine marrow cells with long-term reconstituting potential in vivo

Blood ◽  
1996 ◽  
Vol 88 (11) ◽  
pp. 4149-4158 ◽  
Author(s):  
M Trevisan ◽  
XQ Yan ◽  
NN Iscove
Keyword(s):  
Colony Formation ◽  
Interleukin 1 ◽  
Methyl Cellulose ◽  
Culture Conditions ◽  
Liquid Suspension ◽  
Almost All ◽  
Marrow Cells

Abstract This investigation was directed at separating long-term reconstituting (LTR) stem cells in normal murine marrow from hematopoietic precursors detectable in short-term assays in vitro and in vivo, and then at determining whether purified LTR cells could themselves form colonies in culture. To do so, it was first necessary to identify culture conditions that would induce their growth while preserving their long- term reconstituting capacity. Marrow was cultured with various cytokines in liquid suspension for 4 days, after which the surviving LTR activity was quantitated in a competitive in vivo assay. Activity was preserved near input levels with combined murine c-kit ligand (KL), interleukin-1 (IL-1), IL-6, and IL-11. When the cultures also included tritiated or unlabeled thymidine, LTR potential was eliminated, indicating that essentially all LTR cells were induced into cell cycle with these cytokines. To purify them, marrow was sorted on the basis of Ly6A expression and Rhodamine 123 retention. The Ly6AhiRh123ls fraction contained 85% of total recovered LTR activity but only 1% of the recovered cells measured by multilineage colony formation in spleens or in vitro. This fraction was cultured in methyl cellulose with KL, IL-1, IL-6, and IL-11 for 4 to 6 days, after which colonies were isolated and injected into mice. High levels of permanent reconstitution were achievable in sublethally irradiated W41/W41 mice after the injection of a single reconstituting unit, and limiting dilution analysis estimated the frequency of multilineage LTR at 1 in 11,200 unpurified adult marrow cells. In either lethally irradiated normal or sublethally irradiated W41/W41 mice, 1-year lymphomyeloid reconstitutions were obtained from 1 in 65 to 84 colonies of 2 to 16 dispersed cells, but not from larger colonies or those with clumped cells. The results establish that resting marrow LTR cells can be separated from almost all of the more advanced clonogenic cells that are still pluripotential, can be induced to cycle in culture by defined cytokines with preservation of their reconstituting potential, and can be manipulated and assayed efficiently at single-cell and colony levels.

scholarly journals Primitive human hematopoietic cells displaying differential efflux of the rhodamine 123 dye have distinct biological activities

Blood ◽  
1996 ◽  
Vol 88 (4) ◽  
pp. 1297-1305 ◽  
Author(s):  
N Uchida ◽  
J Combs ◽  
S Chen ◽  
E Zanjani ◽  
R Hoffman ◽  
...  
Keyword(s):  
Stromal Cell ◽  
Biological Activities ◽  
Single Cells ◽  
Hematopoietic Cells ◽  
In Utero ◽  
Rhodamine 123 ◽  
Differentiation Potential ◽  
Cd34 Cells

Human bone marrow (BM) CD34+ cells were stained with the vital dye, rhodamine 123 (Rh123), and analyzed for their biological properties based on the level of dye retention. Heterogeneous rhodamine staining is seen within the CD34+ population, and the staining patterns differ dramatically between fetal BM (FBM), adult BM (ABM) and mobilized peripheral blood (MPB). Kinetic analysis of the efflux of Rh123 from ABM CD34+ cells showed that efflux of Rh123 was most rapid from the most primitive Thy-1+ subset. The efflux of Rh123 could be inhibited by verapamil, suggesting that rhodamine efflux from primitive hematopoietic cells is primarily due to the P-glycoprotein (P-gp) pump or another intracellular transport system affected by verapamil. When four CD34+ subpopulations were plated onto SyS1 BM stromal cell cocultures after 1 to 2 weeks, only wells plated with CD34+ Thy- 1+Rh123lo (low-level Rh123 retention) or CD34+Thy-1+Rh123mid (mid-level Rh123 retention) cells maintained greater than 50% of cells in an uncommitted CD34+33- stage. CD34+Lin- (lineage-negative) cells were fractionated based on Rh123 dye staining into Rh123hi (high-level Rh123 retention), Rh123mid, and Rh123lo and deposited as single cells into long-term SyS1 BM stromal cell cultures. The Rh123mid fraction had immense early proliferative activity in vitro, but lost the ability to form cobblestone areas after 5 to 6 weeks in culture. In contrast, the Rh123lo fraction proliferated more slowly but sustained long-term in vitro hematopoiesis as evidenced by continued cobblestone area-forming cells (CAFC) activity for at least 6 weeks. The Rh123hi fraction showed a plating efficiency similar to that of the Rh123lo or Rh1123mid fractions but did not extensively proliferative in vitro and did not show evidence of CAFC activity. We predicted from these in vitro results that the Rh123lo subsets possesses long-term engrafting potential. Indeed, on transplantation into the SCID-hu bone assay, all long-term engrafting potential and multilineage differentiation potential resided within the Rh123lo-mid but not Rh123hi subset. Furthermore, human marrow subpopulations derived from chimeric sheep after in utero transplantation with CD34+Thy-1+Lin- cells were reisolated based on Rh123 staining. Again, CD34+Lin- subsets showing Rh123lo-mid had long-term growth in culture, whereas Rh123hiCD34+Lin- cells did not. These results show that, after injection of CD34+Thy- 1+Lin- cells into an in utero microenvironment, primitive CD34+ cells maintain a Rh123 phenotype that correlates with their in vitro CAFC activity. Thus, Rh123 staining is an effective way to define functional subsets of primitive hematopoietic cell populations.

Stromal Derived Factor-1–Induced Chemokinesis of Cord Blood CD34+ Cells (Long-Term Culture-Initiating Cells) Through Endothelial Cells Is Mediated by E-Selectin

Blood ◽  
1999 ◽  
Vol 94 (12) ◽  
pp. 4011-4019 ◽  
Author(s):  
Afzal J. Naiyer ◽  
Deog-Yeon Jo ◽  
Jongcheol Ahn ◽  
Robert Mohle ◽  
Mario Peichev ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Adhesion Molecules ◽  
Constitutive Expression ◽  
Transendothelial Migration ◽  
Hematopoietic Stem ◽  
Long Term Culture ◽  
Migration System ◽  
Cd34 Cells

Abstract Homing of hematopoietic stem cells to the bone marrow (BM) involves sequential interaction with adhesion molecules expressed on BM endothelium (BMEC) and chemokine stromal derived factor-1 (SDF-1). However, the mechanism whereby adhesion molecules regulate the SDF-1–induced transendothelial migration process is not known. E-selectin is an endothelial-specific selectin that is constitutively expressed by the BMEC in vivo. Hence, we hypothesized that E-selectin may mediate SDF-1–induced transendothelial migration of CD34+ cells. We show that CD34+ cells express both E-selectin ligand and fucosyltransferase-VII (FucT-VII). Soluble E-selectin–IgG chimera binds avidly to 75% ± 10% of CD34+ cells composed mostly of progenitors and cells with long-term culture-initiating cell (LTC-IC) potential. To assess the functional capacity of E-selectin to mediate CD34+ cell migration in a transendothelial migration system, CD34+ cells were placed on transwell plates coated with interleukin-1β–activated BMEC. In the absence of SDF-1, there was spontaneous migration of 7.0% ± 1.4% of CD34+ cells and 14.1% ± 2.2% of LTC-IC. SDF-1 induced migration of an additional 23.0% ± 4.4% of CD34+cells and 17.6% ± 3.6% of LTC-IC. Blocking MoAb to E-selectin inhibited SDF-1–induced migration of CD34+ cells by 42.0% ± 2.5% and LTC-IC by 90.9% ± 16.6%. To define the mechanism of constitutive expression of E-selectin by the BMEC in vivo, we have found that vascular endothelial growth factor (VEGF165) induces E-selectin expression by cultured endothelial cells. VEGF-stimulated endothelial cells support transendothelial migration of CD34+ cells that could be blocked by MoAb to E-selectin. These results suggest that trafficking of subsets of CD34+ cells with LTC-IC potential is determined in part by sequential interactions with E-selectin and SDF-1.

scholarly journals Stromal cells in myeloid and lymphoid long-term bone marrow cultures can support multiple hemopoietic lineages and modulate their production of hemopoietic growth factors

Blood ◽  
1986 ◽  
Vol 68 (6) ◽  
pp. 1348-1354 ◽  
Author(s):  
A Johnson ◽  
K Dorshkind
Keyword(s):  
Bone Marrow ◽  
Stromal Cells ◽  
Stromal Cell ◽  
Culture Conditions ◽  
B Lymphopoiesis ◽  
Bone Marrow Cultures ◽  
Factor Secretion ◽  
Marrow Cultures

Abstract Hemopoiesis in long-term bone marrow cultures (LTBMC) is dependent on adherent stromal cells that form an in vitro hemopoietic microenvironment. Myeloid bone marrow cultures (MBMC) are optimal for myelopoiesis, while lymphoid bone marrow cultures (LBMC) only support B lymphopoiesis. The experiments reported here have made a comparative analysis of the two cultures to determine whether the stromal cells that establish in vitro are restricted to the support of myelopoiesis or lymphopoiesis, respectively, and to examine how the different culture conditions affect stromal cell physiology. In order to facilitate this analysis, purified populations of MBMC and LBMC stroma were prepared by treating the LTBMC with the antibiotic mycophenolic acid; this results in the elimination of hemopoietic cells while retaining purified populations of functional stroma. Stromal cell cultures prepared and maintained under MBMC conditions secreted myeloid growth factors that stimulated the growth of granulocyte-macrophage colonies, while no such activity was detected from purified LBMC stromal cultures. However, this was not due to the inability of LBMC stroma to mediate this function. Transfer of LBMC stromal cultures to MBMC conditions resulted in an induction of myeloid growth factor secretion. When seeded under these conditions with stromal cell- depleted populations of hemopoietic cells, obtained by passing marrow through nylon wool columns, the LBMC stromal cells could support long- term myelopoiesis. Conversely, transfer of MBMC stroma to LBMC conditions resulted in a cessation of myeloid growth factor secretion; on seeding these cultures with nylon wool-passed marrow, B lymphopoiesis, but not myelopoiesis, initiated. These findings indicate that the stroma in the different LTBMC are not restricted in their hemopoietic support capacity but are sensitive to culture conditions in a manner that may affect the type of microenvironment formed.

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