Faculty Opinions recommendation of Leukemia inhibitory factor extends the lifespan of injured photoreceptors in vivo.

Attempts to maintain or expand primitive hematopoietic stem cells in vitro without the concomitant loss of their differentiative and proliferative potential in vivo have largely been unsuccessful. To investigate this problem, we compared the ability of three cloned bone marrow (BM) stromal cell lines to support the growth of primitive Thy- 1lo Sca-1+H-2Khi cells isolated by fluorescence-activated cell sorting from the BM of Ly-5.2 mice treated 1 day previously with 5-fluo- rouracil. Sorted cells were highly enriched in cobblestone area-forming cells (CAFC), but their frequency was dependent on the stromal cell lines used in this assay (1 per 45 cells on SyS-1; 1 per 97 cells on PA6). In the presence of recombinant leukemia inhibitory factor (LIF), CAFC cloning efficiency was increased to 1 per 8 cells on SyS-1 and 1 per 11 cells on PA6, thus showing the high clonogenicity of this primitive stem cell population. More primitive stem cells with competitive repopulating potential were measured by injecting the sorted cells into lethally irradiated Ly-5.1 mice together with 10(5) radioprotective Ly-5.1 BM cells whose long-term repopulating ability has been “compromised” by two previous cycles of marrow transplantation and regeneration. Donor-derived lymphocytes and granulocytes were detected in 66% of animals injected with 50 sorted cells. To quantitate the maintenance of competitive repopulating units (CRU) by stromal cells, sorted cells were transplanted at limiting dilution before and after being cultured for 2 weeks on adherent layers of SyS-1, PA6, or S17 cells. CRU represented 1 per 55 freshly sorted cells. CRU could be recovered from cocultures supported by all three stromal cell lines, but their numbers were approximately-sevenfold less than on day 0. In contrast, the addition of LIF to stromal cultures improved CRU survival by 2.5-fold on S17 and PA6 cells (approximately two-fold to threefold decline), and enabled their maintenance on SyS-1. LIF appeared to act indirectly, because alone it did not support the proliferation of Thy- 1lo Sca-1+H-2Khi cells in stroma-free cultures. Polymerase chain reaction (RT-PCR) analysis revealed that Interleukin-1beta (IL-1 beta) IL-2, IL-6, granulocyte-colony stimulating factor, granulocyte macrophage-colony stimulating factor, transforming growth factors, LIF, and Steel Factor (SLF) mRNAs were upregulated in SyS-1 within 1 to 6 hours of LIF-stimulation. To determine if increased expression of SLF by LIF-stimulated SyS-1 cells could account for their capacity to support stem cells, sorted calls were cocultured on simian CV-E cells that were transfected with an expression vector encoding membrane-bound SLF, or supplemented with soluble SLF. In both cases, SLF synergized with IL-6 produced endogenously by CV-E cells enabling CAFC growth equivalent to that on LIF-stimulated SyS-1. CAFC development on LIF- stimulated SyS-1 could also be completely abrogated by an anti-SLF antibody. These data provide evidence for a role of LIF in the support of long-term repopulating stem cells by indirectly promoting cytokine expression by BM stroma. Furthermore, we have used quantitative assays to show a maintenance of CRU numbers, with retention of in vivo function following ex vivo culture.

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Leukemia Inhibitory Factor Extends the Lifespan of Injured Photoreceptors In Vivo

Journal of Neuroscience ◽

10.1523/jneurosci.5114-08.2008 ◽

2008 ◽

Vol 28 (51) ◽

pp. 13765-13774 ◽

Cited By ~ 83

Author(s):

S. Joly ◽

C. Lange ◽

M. Thiersch ◽

M. Samardzija ◽

C. Grimm

Keyword(s):

Leukemia Inhibitory Factor ◽

Inhibitory Factor

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227.An inhibitor of leukemia inhibitory factor signalling blocks embryo implantation in the mouse

Reproduction Fertility and Development ◽

10.1071/srb04abs227 ◽

2004 ◽

Vol 16 (9) ◽

pp. 227

Author(s):

E. Dimitriadis ◽

C. Stoikos ◽

M. Baca ◽

W. Fairlie ◽

A. D. Uboldi ◽

...

Keyword(s):

Early Pregnancy ◽

Leukemia Inhibitory Factor ◽

Embryo Implantation ◽

Uterine Horn ◽

Inhibitory Factor ◽

Luminal Epithelium ◽

Pregnant Uterus ◽

Implantation Sites ◽

Post Implantation

Embryo implantation is a critical step in the establishment of pregnancy. Endometrial leukemia inhibitory factor (LIF) is essential for embryo implantation in the mouse (1). Uterine LIF is expressed in the luminal epithelium on Day 3 of pregnancy (D3) (D0�=�day of plug detection) and signals via activation of signal transducer and activator of transcription (Stat) 3 (2). We examined the effect of a novel LIF signalling inhibitor on the phosphorylation (p) of Stat3 during early pregnancy and on embryo implantation in the mouse. We injected LIF inhibitor into one uterine horn and PBS into the other uterine horn of the mouse at D3 and examined the effect on pStat3 immunostaining in the luminal epithelium between 30 and 360�min later. We found no immunoreactive pStat3 in luminal epithelium following treatment with LIF inhibitor at 60 and 90�min but variable staining at other time points. The PBS-treated uterine horn showed intense immunostaining at all times. LIF inhibitor (1mg/kg body weight per day) or PBS was administered to mice (a) subcutaneously, (b) intraperitoneally, at 8-hourly intervals for 3�days from D2, or (c) continuously into the peritoneal cavity via Alzet pumps from D2. No effect was seen on implantation at D6. When LIF antagonist (3.5mg/kg/day) or PBS were administered by Alzet pumps from D2 together with ip injections, 4-hourly from D3 for 36�h, there were no implantation sites in the uteri of treated mice (n�=�5) while the control mice (n�=�4) had 3.6��0.5�sites (P�<�0.001). Histologically, the uteri of the treated mice resembled non-pregnant uterus, while the control uterus resembled post-implantation uterus. The results demonstrate that treatment of mice during early pregnancy with a novel LIF inhibitor blocks LIF action in vivo and embryo implantation. This knowledge is important for development of novel contraceptives. (1) Stewart, C. L., Kaspar, P., Brunet, L. J., Bhatt, H., Gadi, I., Kontgen, F., Abbondanzo, S. J. (1992) Nature 359, 76–79. (2) Cheng, J. G., Chen, J. R., Hernandez, L., Alvord, W. G., Stewart, C. L. (2001) Proc. Natl Acad. Sci. USA 98, 8680–8685.

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Non-neuronal cells inhibit catecholaminergic differentiation of primary sensory neurons: role of leukemia inhibitory factor

Development ◽

10.1242/dev.118.1.83 ◽

1993 ◽

Vol 118 (1) ◽

pp. 83-93 ◽

Cited By ~ 2

Author(s):

G. Fan ◽

D.M. Katz

Keyword(s):

Sensory Neurons ◽

Leukemia Inhibitory Factor ◽

Single Cells ◽

Neuronal Cells ◽

Neuronal Cell ◽

Fold Increase ◽

Inhibitory Effect ◽

Inhibitory Factor ◽

Density Dependent

Although some sensory ganglion cells in mature animals are catecholaminergic, most mammalian sensory neurons that express the catecholamine-synthesizing enzyme tyrosine hydroxylase (TH) do so only transiently during early gangliogenesis in vivo. The lack of TH expression at later stages appears to be due to modulation of this catecholaminergic potential. A previous study showed that the phenotype reappears, for example, when E16.5 and older sensory ganglia are dissociated in culture into single cells, suggesting that extracellular influences can modulate TH expression. Moreover, TH expression in dissociate cultures is cell-density dependent, as a four-fold increase in plating density led to a 30% decrease in the percentage of TH neurons. The present study demonstrates that inhibition of TH expression in high density cultures is mediated by ganglionic non-neuronal cells (NNC), as removal of NNC abolished density-dependent inhibition. Moreover, plating E16.5 trigeminal neurons at low density on top of NNC monolayers resulted in an 85% decrease in the percentage of TH neurons. Treatment of cultures with non-neuronal cell conditioned medium (NNC-CM) reproduced the effect of coculture with NNC, suggesting that diffusible factors from NNC were involved in the inhibition of TH. The inhibitory effect of NNC-CM was mimicked by treatment of dissociate cultures with ciliary neurotrophic factor (CNTF) and leukemia inhibitory factor (LIF). However, immunoprecipitation of NNC-CM with antibodies against LIF or CNTF showed that only anti-LIF antibodies were able partially to remove the TH inhibitory activity of NNC-CM. Therefore, LIF is one, but not the only, factor mediating NNC inhibition of TH expression in cultured sensory neurons. In summary, these data indicate that ganglionic NNC can regulate sensory transmitter phenotype in culture by inhibiting expression of specific molecular traits. The finding that LIF can partially account for the inhibitory effect of ganglionic NNC on TH expression suggests a novel role for this cytokine in regulating differentiation of catecholaminergic properties in sensory neurons.

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Cholinergic Neuronal Differentiation Factor (CDF)/Leukemia Inhibitory Factor (LIF) Binds to Specific Regions of the Developing Nervous System in Vivo

Developmental Biology ◽

10.1006/dbio.1994.1167 ◽

1994 ◽

Vol 163 (2) ◽

pp. 516-520 ◽

Cited By ~ 18

Author(s):

Liequn Qiu ◽

Paulette Bernd ◽

Keiko Fukada

Keyword(s):

Nervous System ◽

Neuronal Differentiation ◽

Leukemia Inhibitory Factor ◽

Inhibitory Factor ◽

Differentiation Factor ◽

Developing Nervous System

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An In Vitro and In Vivo Evidence That Downregulation of Leukemia Inhibitory Factor (LIF) Receptor (LIF-R) Decreases the Metastatic Potential of Human Rhabdomyosarcoma (RMS) Cells.

Blood ◽

10.1182/blood.v108.11.2561.2561 ◽

2006 ◽

Vol 108 (11) ◽

pp. 2561-2561

Author(s):

Marcin Wysoczynski ◽

Katarzyna Miekus ◽

Anna Marcinkowska ◽

Anna Janowska-Wieczorek ◽

Mariusz Z. Ratajczak

Keyword(s):

Skeletal Muscle ◽

Bone Marrow ◽

Cell Line ◽

Cell Lines ◽

Leukemia Inhibitory Factor ◽

Biological Significance ◽

Human Cells ◽

Inhibitory Factor

Abstract Rhabdomyosarcoma (RMS) and skeletal muscle-derived tumors frequently infiltrate bone marrow (BM). We have demonstrated that the stromal-derived factor (SDF)-1-CXCR4 receptor (Blood2002;100:2597) and hepatocyte growth factor (HGF)-c-Met receptor (Cancer Res. 2003;63:7926) play an important role in RMS metastasis to BM. Leukemia inhibitory factor (LIF) is a well known factor that plays an important role in skeletal muscle development/regeneration and similarly as SDF-1 and HGF is secreted by BM stroma. This prompted us to examine whether the LIF-LIF receptor (LIF-R) axis affects the biology/metastasis of RMS cells. We employed in our studies, human established RMS cell lines, as well as RMS samples isolated from patients and noticed that LIF-R was expressed not only on established human RMS cell lines (7/7) but more importantly, it was also detectable in patient samples (23/23). We also found that in RMS cells LIF stimulatesphosphorylation of MAPKp42/44, AKT and STAT3,chemotaxis and adhesion andincreases resistance to cytostatics (e.g., etoposide). These LIF-mediated effects were inhibited after downregulating the LIF-R by siRNA. To learn more on the biological significance of the LIF-LIF-R axis in vivo we employed two models. First, human RMS cells (RH-30) were exposed or not exposed to LIF-R siRNA and subsequently injected into SCID™-Beige immunodeficient mice. To estimate the number of RMS cells that seed to BM and liver in these animals, we isolated DNA and using real- time RT-PCR, amplified human a-satellite sequences and murine b-actin. The number of human cells present in murine organs was subsequently calculated from a standard curve derived from mixing varying numbers of human cells with a constant number of murine cells. We noticed that downregulation of LIF-R by siRNA significantly decreased the number of human RMS cells in murine BM and liver (x4 and x2 respectively). In a second model, the RH30 cell line was selected by repetitive chemotaxis for cells that are highly responsive to LIF (RH-30 L) and subsequently the cells from parental RH-30 cell line and RH-30 L cells were injected intramuscularly. Six weeks after tumour inoculation, we detected more metastasis in bone marrow and lungs in mice injected with RH-30L cells as compared to parental RH-30 clone (x6 and x3 respectively). In conclusion, we present evidence for the first time that the inhibition of LIF-LIF-R axis may decrease the invasive potential of human RMS both in vitro and in vivo. Hence, molecular targeting of LIF-LIF-R axis could possibly become a more effective new strategy to control the progression and metastasis of RMS.

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