Granulocyte Colony-stimulating Factor Gene Research Articles

Molecular and functional characterization of two granulocyte colony stimulating factors in goldfish (Carassius auratus L.).

Granulocyte colony-stimulating factor (GCSF) is a member of the hematopoietic growth factor family that acts primarily on neutrophils and neutrophilic precursors to promote cell proliferation and differentiation. Although multiple GCSF genes have been found in teleosts, knowledge of their functions during fish hematopoietic development is still limited. Here, we report for the first time the molecular and functional characterization of two goldfish GCSFs (gfGCSF-a and gfGCSF-b). The open reading frame (ORF) of the gfGCSF-a and gfGCSF-b cDNA transcript consisted respectively of 624bp and 678bp with its ORF encoding 207 and 225 amino acids (aa), with a 17 aa signal peptide for each gene and a conserved domain of the IL-6 superfamily. Treatment of goldfish head kidney leukocytes (HKLs) with LPS increased gfGCSF-a and gfGCSF-b mRNA expression levels, also exposure of HKLs to either heat-killed or live A. hydrophila, induced transcriptional upregulation of gfGCSF-a and gfGCSF-b levels. Recombinant gfGCSF-a and gfGCSF-b protein (rgGCSF-a and rgGCSF-b) induced a dose-dependent production of TNFα and IL-1β from goldfish neutrophils. In vitro experiments showed rgGCSF-a and rgGCSF-b differentially promoted the proliferation and differentiation of leukocytes in goldfish. Furthermore, treatment of HKLs with rgGCSF-a showed significant upregulation of mRNA levels of the hematopoietic transcription factor GATA2, Runx1, MafB, and cMyb, while gfGCSF-b induces not only all four transcriptional factors mentioned above but also CEBPα. Our results indicate that goldfish GCSF-a and GCSF-b are important regulators of neutrophil proliferation and differentiation, which could stimulate different stages and lineages of hematopoiesis.

TAMI-52. G-CSF SECRETED BY EPIGENETICALLY REPROGRAMMED MUTANT IDH1 GLIOMA STEM CELLS, REVERSES THE MYELOID CELLS’-MEDIATED IMMUNOSUPPRESSIVE TUMOR MICROENVIRONMENT

Abstract Mutation in isocitrate dehydrogenase (mIDH) is the main genetic lesion that defines clinical glioma subtypes and prognosis. This gain of function mutation is associated with the production of the oncometabolite, R-2-hydroxyglutarate, that inhibits α-ketoglutarate dependent enzymes such as TET2 and the Jumonji-C domain containing demethylases. The resultant epigenetic modifications elicit profound effects on the tumor biology and on the glioma-infiltrating immune cells. Here, we report that in genetically engineered mouse glioma models(1), IDH1 mutation caused an expansion of tumor infiltration granulocytes. Upon phenotypic and functional characterization, we uncovered that granulocytes in mIDH1 glioma express low level of immunosuppressive molecules and did not inhibit T-cell function. Single-cell sequencing revealed that these granulocytes are heterogeneous and composed of three distinct populations; neutrophils, pre-neutrophils, and a small fraction of immunosuppressive PMN-MDSCs. Moreover, primary human gliomas showed a higher cellular fraction exhibiting the PMN-MDSCs gene signature in wtIDH1 tumors than the mIDH1 tumors. The mechanism by which mIDH1 mediates non-immune suppressive granulocytes expansion involves epigenetic reprogramming which leads to enhanced expression of granulocyte colony-stimulating factor (G-CSF) in stem-like cells. High G-CSF gene expression is correlated with favorable patient outcome solely in LGG-astrocytoma with mIDH1. Thus, G-CSF represents a potential therapeutic that can be harnessed to improve immunotherapeutic responses in wild type IDH1 glioma patients.

Comparative Analysis of the Biosimilar and Innovative G-CSF Modulated Pathways on Umbilical Cord Blood-Derived Mononuclear Cells.

Biosimilars of granulocyte colony-stimulating factor (G-CSF) have been routinely introduced into clinical practice. However, not functional genomics characterization has been performed yet in comparison with the innovator G-CSF. This study aimed to evaluate the transcriptomic changes in an in vitro model of umbilical cord blood cells (UBC) exposed to G-CSF for the identification of their modulated pathways. Umbilical cord blood cells–derived mononuclear cells (MNCs) were treated with biosimilar and innovator G-CSF for further gene expression profiling analysis using a microarray-based platform. Comparative analysis of biosimilar and innovator G-CSF gene expression signatures allowed us to identify the most commonly modulated pathways by both drugs. In brief, we observed predominantly upmodulation of transcripts related to PI3K-Akt, NF-kappaB, and tumor necrosis factor (TNF) signaling pathways as well as transcripts related to negative regulation of apoptotic process among others. In addition, hematopoietic colony-forming cell assays corroborate the G-CSF phenotypic effects over UBC-derived MNCs. In conclusion, our study suggests that G-CSF impacts UBC-derived cells through the modulation of several signaling pathways associated with cell survival, migration, and proliferation. The concordance observed between biosimilar and innovator G-CSF emphasizes their similarity in regards to their specificity and biological responses.

Muscle-secreted granulocyte colony-stimulating factor functions as metabolic niche factor ameliorating loss of muscle stem cells in aged mice.

The function and number of muscle stem cells (satellite cells, SCs) decline with muscle aging. Although SCs are heterogeneous and different subpopulations have been identified, it remains unknown whether a specific subpopulation of muscle SCs selectively decreases during aging. Here, we find that the number of SCs expressing high level of transcription factor Pax7 (Pax7Hi ) is dramatically reduced in aged mice. Myofiber-secreted granulocyte colony-stimulating factor (G-CSF) regulates age-dependent loss of Pax7Hi cells, as the Pax7Hi SCs are replenished by exercise-induced G-CSF in aged mice. Mechanistically, we show that transcription of G-CSF (Csf3) gene in myofibers is regulated by MyoD in a metabolism-dependent manner. Furthermore, myofiber-secreted G-CSF acts as a metabolic niche factor required for establishing and maintaining the Pax7Hi SC subpopulation in adult and physiological aged mice by promoting the asymmetric division of Pax7Hi and Pax7Mi SCs. Together, our findings uncover that muscles provide a metabolic niche regulating Pax7 SC heterogeneity in mice.

Functional Secretion of Granulocyte Colony Stimulating Factor in Bacillus subtilis and Its Thermogenic Activity in Brown Adipocytes

Granulocyte colony-stimulating factor (G-CSF) is involved in generation of colonies hematopoietic cells by stimulation of bone marrow cells, resulting in the survival, proliferation, differentiation, and function of neutrophil precursors and mature neutrophils. To express and secrete G-CSF in Bacillus system, the G-CSF gene was amplified using gene-specific primers and template DNA (pUNO1-hGCSFb). As a result, the PCR product of 530 bp was obtained, sequenced, and analyzed using the BLAST program. The open reading frame encoded a 204-amino acid polypeptide precursor consisting of the 30-residue signal sequence and a 174-residue mature polypeptide. Recombinant secretion vector (pRBAS-CSF3, 6.96 kb) was constructed using pRBAS vector which contains promoter (0.45 kb) and signal sequence (87 bp) of alkaline protease gene (aprE), ribosome binding site (GGAGAGGG) and transferred to Bacillus subtilis LKS. G-CSF protein was secreted and optimized to increase the productivity (19% of total secreted proteins, 0.12 mg/ml). The culture broth was harvested and followed by metal chelating, ethanol precipitation, and gel chromatography. The purified G-CSF was tested for thermogenic activity in cultured brown adipocytes. G-CSF activated HIB1B brown adipocytes by increasing expression levels of brown fat-specific marker proteins (UCP1 and PRDM16) and genes (Lhx8, Ppargc1, Prdm16, Ucp1, and Zic1) in HIB1B brown adipocytes. This result suggests that G-CSF per se or G-CSF-containing foodstuff can be used to treat obesity.

An in vitro assessment for evaluating the efficiency of β-d-mannuronic acid (M2000) in myelodysplastic syndrome.

β-d-Mannuronic acid (M2000), a novel non-steroidal anti-inflammatory drug (NSAID) with immunosuppressive properties, has been previously shown to exhibit potential therapeutic effects on autoimmune diseases. Immunosuppression therapy has been a standard approach for myelodysplastic syndrome (MDS) for many years. We evaluated the effect of M2000 on isolated peripheral blood mononuclear cells (PBMCs) from patients with MDS. The PBMCs were isolated from 13 patients with MDS and 13 normal donors. The cells were then treated with low, moderate, and high doses of M2000 and diclofenac as a control group. The level of interleukin (IL)-6, tumor necrosis factor alpha (TNF-α), IL-3, granulocyte colony-stimulating factor (G-CSF) gene expression and the serum level of IL-6 and TNF-α production were evaluated by real-time polymerase chain reaction and enzyme-linked immunosorbent assay methods, respectively. Our findings indicated a significant reduction in the production of IL-6 and TNF-α as inflammatory cytokines. Furthermore, the level of G-CSF gene expression was significantly increased. In conclusion, M2000, a newly designed NSAID, has a remarkable effect on isolated PBMC in patients with MDS, which might bring a potential hope for its oral administrations in these patients.

Protease-activated receptor 2 (PAR2) upregulates granulocyte colony stimulating factor (G-CSF) expression in breast cancer cells

Protease-activated receptor 2 (PAR2) is a G-protein coupled receptor which is activated upon cleavage of its N-terminal region. PAR2 has been associated with many aspects regarding tumor progression, such as the production of pro-tumoral cytokines. Granulocyte colony-stimulating factor (G-CSF) is a cytokine essential to neutrophil production and maturation, and it is often overexpressed in tumors. In this study, we evaluated the ability of PAR2 to modulate G-CSF expression. PAR2 and G-CSF were significantly more expressed in metastatic (4T1 and MDA-MB-231) as compared to non-metastatic (67NR and MCF7) breast cancer cell lines. In addition, PAR2 stimulation by a synthetic agonist peptide significantly increased G-CSF gene expression in the metastatic cell lines. Knockdown of PAR2 in 4T1 cells decreased G-CSF expression and secretion. In addition, treatment of 4T1 with the commercial PAR2 antagonist, ENMD-1068, significantly decreased G-CSF expression. cBioPortal analyses of the TCGA database showed a significant co-occurrence of G-CSF and PAR2 gene overexpression in breast cancer samples. In conclusion, our data suggest that PAR2 contributes to G-CSF expression in breast cancer cells, possibly favoring tumor progression.

Granulocyte colony-stimulating factor gene rs1042658 variant and susceptibility to idiopathic recurrent pregnancy loss: A case-control study

Granulocyte colony-in stimulating factor (G-CSF) gene can be a potential candidate gene implicated recurrent pregnancy loss (RPL), a common complication of pregnancy with the prevalence of 1-5% among women of reproductive age. To investigate the association between rs1042658 polymorphism in the 3' untranslated region (3'UTR) of G-CSF gene and the risk of unexplained RPL among Iranian women. In total, 122 women with unexplained RPL and 140 healthy postmenopausal women as a control group were enrolled in this case-control study. Tetra-primer amplification refractory mutation system-polymerase chain reaction was performed to determine the rs1042658 genotypes in all subjects. Statistically significant differences were detected between the distribution frequencies of both heterozygote CT, and carriage of T allele (TT+CT) genotypes of the rs1042658 between case and control groups. Allelic association was not observed with RPL. Regarding the results of the present study, G-CSF rs1042658 gene polymorphism could be considered as a probable risk factor for unexplained RPL among Iranian women.

Altered Expression of Hematopoiesis Regulatory Genes in the Bone Marrow Mesenchymal Stem Cells of Patients of Aplastic Anemia

Mesenchymal stem cells (MSC) are an important component of the hematopoietic niche in the bone marrow (BM) and regulate hematopoiesis by producing a variety of cytokines and growth factors. In aplastic anemia (AA), most of the studies have attributed the reduced hematopoiesis to a defect in hematopoietic stem cells (HSC) and limited data is available on the role of BM-MSC in AA. Therefore, the objective of the present study was to evaluate the expression of hematopoiesis regulatory genes, viz. granulocyte colony stimulating factor (G-CSF), stromal cell derived factor (SDF-1), stem cell factor (SCF), tumor necrosis factor-alpha (TNF-α) macrophage inflammatory protein-1 alpha (MIP-1α) and transforming growth factor-beta (TGF-β) in BM-MSC of patients with AA and compare it with BM-MSC of control group.Twenty patients of idiopathic acquired AA with a median age of 25.5 years (range: 12-64 years) were included in the study. The control group consisted of 10 healthy volunteers and 10 patients with iron deficiency anemia or immune thrombocytopenic purpura. The median age of the control group was 20 years (range: 11-62 years). The BM-MSC were isolated and cultured as per protocol standardized and previously published by us. Third passage cells were used in the study. The MSC were characterized both by their phenotypic markers and by their ability to differentiate into adipogenic and osteogenic lineages. The expression of hematopoiesis regulatory genes was studied by real-time quantitative polymerase chain reaction (qRT-PCR). The GAPDH was used as the housekeeping gene to normalize the transcript levels and the fold change in the gene expression was calculated by 2-ΔΔCtmethod.The BM-MSC of AA patients and controls had similar morphology and expression of mesenchymal markers CD73, CD105, CD90 and CD166, absence of expression of hematopoietic markers CD13, CD34 and CD45 and of HLA-DR. However, the BM-MSC of AA patients exhibited a higher adipogenic and a lower osteogenic differentiation in comparison to those of controls. Further, the BM-MSC of AA patients in comparison to those of control group, had a higher expression of G-CSF (fold increase: 1.99; p<0.0001), SDF-1 (fold increase: 1.37; p<0.01) and TNF-α (fold increase: 10.68; p<0.0001) and a very low expression of MIP-1α (fold decease: 50.0; p<0.0001) transcripts. The expression of SCF and TGF-β transcripts were comparable in the BM-MSC of both the groups (p>0.05).Though AA patients have been shown to have elevated levels of G-CSF in the peripheral blood and BM but there is only one previous report on G-CSF gene expression in BM-MSC of AA, in which a higher expression was observed and thus corroborates with our data. There is no data available on SDF-1 levels in the peripheral blood and bone marrow of AA patients. We have observed higher gene expression of SDF-1 in BM-MSC of AA patients. The higher expression of G-CSF and SDF-1, pro-hematopoietic factors, in AA may be due to a compensatory response of the BM stroma to boost the hematopoiesis. Our observation of higher TNF-α gene expression in BM-MSC corroborates with previous reports on higher levels of this anti-hematopoietic cytokine in the BM plasma of patients with AA and indicates that MSC could contribute to the increase in the TNF-α level in the BM of AA patients. A conspicuous observation of our study was a markedly decreased expression of MIP-1α gene in BM-MSC of AA and to the best of our knowledge this is the first report on MIP-1α in AA. MIP-1α is a chemokine which has been shown to inhibit proliferation of HSC in vitro and thus may help to maintain HSC in an undifferentiated state. Furthermore, MIP-1α has also been reported to mediate interaction of HSC with stromal cells in BM and may have a role in supporting hematopoiesis. Its precise role in AA needs to be studied further. We are currently studying the levels of these cytokines/growth factors in the BM plasma of the same cohort of AA patients and controls and the data will be presented.Our study thus shows that BM-MSC of AA patients have altered expression of hematopoiesis regulatory genes which may contribute to the pathobiology of the disease. DisclosuresNityanand:Sanjay Gandhi Post Graduate Institute of Medical Sciences: Employment, Research Funding. Tripathy:Sanjay Gandhi Post Graduate Institute of Medical Sciences: Employment. Chaturvedi:Dept of Biotechnology, Govt of India: Employment. Minocha:Dept of Science and Technology, Govt of India: Other: PhD scholarship. Sharma:Sanjay Gandhi Post Graduate Institute of Medical Sciences: Employment. Rahman:SGPGI, Lucknow , India: Employment, Research Funding.

DEVELOPMENT OF AUTONOMOUSLY REPLICATING VIRAL RNA TO EXPRESS THE RECOMBINANT HUMAN GRANULOCYTE COLONY-STIMULATING FACTOR

Recombinant human granulocyte colony-stimulating factor (G-CSF) produced in cultured mammalian cells undergoes proper posttranslational modifications and, thereby, possesses better pharmacological properties in comparison with the homologous protein expressed in bacteria. Biopharmaceuticals derived from cell culture tend to be expensive because of lower yields compared to bacterially expressed competitors and numerous issues with the scalability of production. Particular limitation of scalability pertains to delivery of expression vectors to the cell culture. Natural and efficient way to deliver foreign DNA or RNA to cell is a viral infection. We intended to develop the viral genome capable of G-CSF expression.Objectives: To develop autonomously replicating viral RNA capable of heterologous expression of the G-CSF in cultured mammalian cells.Methods: Genetic engineering, cell culture, and virology.Results: Viable genome of the Venezuelan equine encephalomyelitis virus (VEE) was constructed. The G-CSF gene was synthesized de novo. Gene cassette GFP-2A-G-CSF was constructed for simultaneous expression of the fluorescent marker of viral replication (GFP) and the product of interest. Recombinant viral genome VEE/GFP-2A-G-CSF was assembled; its viability was confirmed upon transfection to the BHK-21 cells.Conclusion: Genetic engineering of the cDNA copies of the genomes of RNA viruses provides excessive opportunities to develop mammalian expression systems. We achieved production of recombinant proteins in cultured mammalian cells transfected with the VEE viral RNA carrying the inserted genes of marker protein and G-CSF.

Yam storage protein dioscorins modulate cytokine gene expression in BALB/c and C57BL/6 lymphocytes

This study aimed to evaluate the effects of dioscorins isolated from 2 yam species, Dioscorea alata (Da-dioscorins) and Dioscorea japonica (Dj-dioscorins), on mouse immune activities. Results from cytokine array indicated that Dj-dioscorins increased the production of tumor necrosis factor (TNF)-α, interleukin (IL)-2, IL-3, IL-6, IL-10, IL-12p40, IL-13, monocyte chemoattractant protein (MCP)-1, regulated on activation, normal T cell expressed and secreted (RANTES), and granulocyte colony-stimulating factor (GCSF) in the spleen cells of BALB/c mice. In RAW264.7 macrophage, Da-dioscorins upregulated the expression of TNF-α, IL-1β, IL-6, IL-10, RANTES, MCP-1, and GCSF genes to a greater extent than Dj-dioscorins did. TNF-α, IL-1β, IL-6, IL-10, and RANTES gene expression was higher in spleen cells than in bone marrow and thymus cells in Da-dioscorin- or Dj-dioscorin-treated BALB/c and C57BL/6. Overall, our results suggest that dioscorins exert distinct immunomodulatory effects on mouse immune cells, and that different mouse strains respond differently to dioscorins.

Macrophage depletion disrupts immune balance and energy homeostasis.

Increased macrophage infiltration in tissues including white adipose tissue and skeletal muscle has been recognized as a pro-inflammatory factor that impairs insulin sensitivity in obesity. However, the relationship between tissue macrophages and energy metabolism under non-obese physiological conditions is not clear. To study a homeostatic role of macrophages in energy homeostasis, we depleted tissue macrophages in adult mice through conditional expression of diphtheria toxin (DT) receptor and DT-induced apoptosis. Macrophage depletion robustly reduced body fat mass due to reduced energy intake. These phenotypes were reversed after macrophage recovery. As a potential mechanism, severe hypothalamic and systemic inflammation was induced by neutrophil (NE) infiltration in the absence of macrophages. In addition, macrophage depletion dramatically increased circulating granulocyte colony-stimulating factor (G-CSF) which is indispensable for NE production and tissue infiltration. Our in vitro study further revealed that macrophages directly suppress G-CSF gene expression. Therefore, our study indicates that macrophages may play a critical role in integrating immune balance and energy homeostasis under physiological conditions.

Inducible deletion of the Blimp-1 gene in adult epidermis causes granulocyte-dominated chronic skin inflammation in mice

B lymphocyte-induced maturation protein-1 (Blimp-1) is a transcriptional repressor important for the differentiation and function of several types of immune cells. Because skin serves as a physical barrier and acts as an immune sentinel, we investigated whether Blimp-1 is involved in epidermal immune function. We show that Blimp-1 expression is reduced in skin lesions of some human eczema samples and in stimulated primary keratinocytes. Epidermal-specific deletion of PR domain containing 1, with ZNF domain (Prdm1), the gene encoding Blimp-1, in adult mice caused spontaneously inflamed skin characterized by massive dermal infiltration of neutrophils/macrophages and development of chronic inflammation associated with higher levels of cytokines/chemokines, including granulocyte colony-stimulating factor (G-CSF), and enhanced myelopoiesis in bone marrow. Deletion of Prdm1 in the epidermis of adult mice also led to stronger inflammatory reactions in a tape-stripping test and in a disease model of contact dermatitis. The elevated G-CSF produced by keratinocytes after deletion of Prdm1 in vitro was mediated by the transcriptional activation of FBJ osteosarcoma oncogene (Fos) and fos-like antigen 1 (Fosl1). Systemic increases in G-CSF contributed to the inflammatory responses, because deletion of the G-CSF gene [colony stimulating factor 3, (Csf3)] prevented neutrophilia and partially ameliorated the inflamed skin in Prdm1-deficient mice. Our findings indicate a previously unreported function for Blimp-1 in restraining steady-state epidermal barrier immunity.

Double gene therapy with granulocyte colony-stimulating factor and vascular endothelial growth factor acts synergistically to improve nerve regeneration and functional outcome after sciatic nerve injury in mice

Peripheral-nerve injuries are a common clinical problem and often result in long-term functional deficits. Reconstruction of peripheral-nerve defects is currently undertaken with nerve autografts. However, there is a limited availability of nerves that can be sacrificed and the functional recovery is never 100% satisfactory. We have previously shown that gene therapy with vascular endothelial growth factor (VEGF) significantly improved nerve regeneration, neuronal survival, and muscle activity. Our hypothesis is that granulocyte colony-stimulating factor (G-CSF) synergizes with VEGF to improve the functional outcome after sciatic nerve transection. The left sciatic nerves and the adjacent muscle groups of adult mice were exposed, and 50 or 100μg (in 50μl PBS) of VEGF and/or G-CSF genes was injected locally, just below the sciatic nerve, and transferred by electroporation. The sciatic nerves were transected and placed in an empty polycaprolactone (PCL) nerve guide, leaving a 3-mm gap to challenge nerve regeneration. After 6weeks, the mice were perfused and the sciatic nerve, the dorsal root ganglion (DRG), the spinal cord and the gastrocnemius muscle were processed for light and transmission electron microscopy. Treated animals showed significant improvement in functional and histological analyses compared with the control group. However, the best results were obtained with the G-CSF+VEGF-treated animals: quantitative analysis of regenerated nerves showed a significant increase in the number of myelinated fibers and blood vessels, and the number of neurons in the DRG and motoneurons in the spinal cord was significantly higher. Motor function also showed that functional recovery occurred earlier in animals receiving G-CSF+VEGF-treatment. The gastrocnemius muscle showed an increase in weight and in the levels of creatine phosphokinase, suggesting an improvement of reinnervation and muscle activity. These results suggest that these two factors acted synergistically and optimized the nerve repair potential, improving regeneration after a transection lesion.

A 3,387 bp 5′-flanking sequence of the goat alpha-S1-casein gene provides correct tissue-specific expression of human granulocyte colony-stimulating factor (hG-CSF) in the mammary gland of transgenic mice

A new expression vector containing the 1,944 bp 5'-flanking regulatory region together with exon 1 and intron 1 of the goat alpha-S1-casein gene (CSN1S1), the full-sized human granulocyte colony-stimulating factor gene (hGCSF) and the 3'-flanking sequence of the bovine CSN1S1, was created. The vector DNA was used for generation of four mouse transgenic lines. The transgene was integrated into chromosomes 8 and 12 of two founders as 2 and 5 copies, respectively. Tissue-specific secretion of hG-CSF into the milk of transgenic mice was in the range of 19-40 μg/ml. RT-PCR analysis of various tissues of the transgenic mice demonstrated that expression of hGCSF was detected in only the mammary gland in the progeny of all founders. Moreover, cells were shown to be positive for hG-CSF by immunofluorescent analysis in the mammary glands but not in any other tissues. There were no signs of mosaic expression in the mammary gland. Trace amounts of hG-CSF were detected in the serum of females of two transgenic lines during lactation only. However, no transgenic mice showed any changes in hematopoiesis based on the number of granulocytes in blood. Immunoblotting of hG-CSF in the milk of transgenic mice revealed two forms, presumably the glycosylated and non-glycosylated forms. The hematopoietic activity of hG-CSF in the milk of transgenic females is comparable to that of recombinant G-CSF. In general, the data obtained in this study show that the new expression vector is able to provide correct tissue-specific expression of hG-CSF with high biological activity in transgenic mice.

누에세포를 이용한 인간 G-CSF의 발현 및 생산

조혈촉진 cytokine인 Granulocyte colony stimulating factor (G-CSF)는 골수세포를 자극하여 granulocyte로 증식, 분화시키는 기능을 가지며, 현재 아주 고가의 치료제로 사용되고 있다. 인간 G-CSF (hG-CSF)를 아직 시도되지 않은 누에 유래 세포주인 BM5 세포에서 발현시키고 생산 효율을 높이기 위해 hG-CSF cDNA를 변형하였다. hG-CSF의 cDNA의 endoplasmic reticulum (ER) signal sequence 부분을 누에의 소포체에서 분비되는 단백질인 prophenoloxidase (PPAE), protein disulfide isomerase (PDI)와 bombyxin (BX)에서 유래한 누에특이 ER signal sequence로 대체한 hG-CSF의 cDNA 함유 벡터를 구축하였다. 이들 벡터를 사용하여 형질전환한 BM5 세포의 배양액에 분비된 G-CSF 단백질을 western blot으로 분석하여 발현을 확인하였다. 누에특이 ER signal sequence들로 대체된 hG-CSF cDNA를 포함하는 벡터에 의한 hG-CSF 단백질 생산이 인간 G-CSF cDNA가 든 벡터에 의한 hG-CSF의 생산보다 월등히 효율적이었다. 또한, PPAE-signal sequence를 포함하는 hG-CSF 단백질은 배양배지에서 형질전환 4일 후에 최고에 달하였고, 7 일째까지 비슷한 양이 배지 내에서 검출되었다. 이상의 결과는 인간유래 유전자가 곤충세포 내에서 발현 될 때 인간유래 유전자 보다는 곤충 유전자발현 시스템에 맞게 변형했을 경우 더 효율적인 단백질 발현을 얻을 수 있음을 보여 준다. Granulocyte colony stimulating factor (G-CSF) is a hematopoietic cytokine that stimulates bone marrow cells to proliferate and differentiate into granulocytes. G-CSF is approved and used for therapeutic purposes. The endoplasmic reticulum (ER) signal peptide of hG-CSF was replaced with silkworm-specific signal peptides to express and efficiently secrete recombinant hG-CSF by silkworm cells. Plasmids that contain cDNAs for hG-CSF and hG-CSF fused with silkworm- specific signal peptides of prophenoloxidase activating enzyme (PPAE), protein disulfide isomerase (PDI), and bombyxin (BX) were constructed. The G-CSF protein was expressed in insect cell line BM5 and was detected by western blot analysis. The cells transfected with plasmids containing rhG-CSF genes with silkworm-specific signal sequences released mature rhG-CSF protein more efficiently than the cells transfected with pG-CSF, the plasmid containing human G-CSF gene, including its own signal sequence. The production of hG-CSF reached maximal level at four days post-transfection and remained at a high level until 7 days post-transfection. These data demonstrate that the modification of the human G-CSF mimic to insect proteins synthesized in ER greatly improves the production of the protein.

Abstract 5196: Granulocyte-colony stimulating factor (G-CSF) plays a causative role for H-Ras-mediated invasion and migration of human breast epithelial cells

Abstract The whole human genome microarray on normal MCF10A, N-Ras-transformed, non-invasive MCF10A and H-Ras-transformed invasive MCF10A human breast epithelial cells revealed that the granulocyte-colony stimulating factor (G-CSF) was most highly upregulated in an H-Ras-specific manner. The present study investigated whether G-CSF plays a causative role for H-Ras-mediated MCF10A cell invasion and migration. Importantly, siRNA-mediated knockdown of G-CSF expression significantly reduced H-Ras-induced matrix metalloproteinase(MMP)-2 expression as well as invasion/migration. Activations of Rac1, MKK3/6 and p38 MAPK were inhibited by siRNA-knockdown of G-CSF. The induction of G-CSF expression conferred the invasive/migratory phenotype to parental MCF10A cells. Expression of MMP-2 and activation of signaling molecules Rac1, MKK3/6 and p38 MAPK were increased by G-CSF induction. Taken together, this study revealed G-CSF gene as a candidate marker for metastatic potential of breast epithelial cells. Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5196.

Synergistic effect of vascular endothelial growth factor and granulocyte colony‐stimulating factor double gene therapy in mouse limb ischemia

Vascular endothelial growth factor (VEGF) has mostly been tested to treat ischemic diseases, although the outcomes obtained are not satisfactory. Our hypothesis is that the local transient expression of VEGF and stem cell mobilizer granulocyte colony-stimulating factor (G-CSF) genes in ischemic limbs can complement their activities and be more efficient for limb recovery. Limb ischemia was surgically induced in mice and 50 microg of VEGF and/or G-CSF genes were locally transferred by electroporation. After 3-4 weeks, evidence of necrosis by visual inspection, capillary density, muscle mass, muscle force and hematopoietic cell mobilization were evaluated. After 4 weeks, 70% and 90% of the animals of the ischemic group (IG) and VEGF-treated group (VG), respectively, presented limb necrosis, in contrast to only 10% observed in the group of mice treated with both VEGF and G-CSF genes (VGG). Recovery of muscle mass and muscle force was higher than 60% in the VGG compared to the non-ischemic group. The mobilization of Sca1+ cells and neutrophils was also higher in the VGG, which may explain the lower level of necrosis observed in this group (22%, in contrast to 70% in the IG). Capillary density and degree of fibrosis were determined in weeks 3 and 4, and also showed a clear benefit as a result of the use of the G-CSF and VEGF genes together. Gene therapy using VEGF and G-CSF demonstrated a synergistic effect promoting vessel and tissue repair in mouse hind limb ischemia.

Molecular cloning and expression of cDNAs for two distinct granulocyte colony stimulating factor genes from black rockfish Sebastes schlegelii

Granulocyte-colony stimulating factor (G-CSF) is a cytokine that stimulates the proliferation and differentiation of hematopoietic progenitor cells committed to the neutrophil/granulocyte lineage. Here, we report the two distinct granulocyte colony stimulating factor homologues from black rockfish Sebastes schlegelii. The G-CSF homologue cDNAs were isolated from the black rockfish LPS or Con A/PMA stimulated leukocyte cDNA libraries. The cDNA for the Black rockfish G-CSF-1 homologue predicts a peptide of 202 amino acids that is the closest to the Bastard halibut ( Paralichthys olivaceus) G-CSF, whereas the cDNA of the Black rockfish G-CSF-2 homologue predicts a peptide of 212 amino acids that is the closest to the Fugu ( Takifugu rubripes). In a healthy fish, the mRNAs of both G-CSF homologues were predominantly expressed in leukocytes, spleen, and gill. Expression of the black rockfish G-CSF-1 homologue was induced in peripheral blood leukocytes (PBLs) after stimulation with LPS, Con A/PMA, or Poly I:C, and G-CSF-2 homologue was strongly induced in PBLs after stimulation with Con A/PMA for 24 h only.

Hochuekkito, a Kampo (Traditional Japanese Herbal) Medicine, and its Polysaccharide Portion Stimulate G-CSF Secretion from Intestinal Epithelial Cells

Kampo (traditional Japanese herbal) medicines are taken orally due to which the gastric mucosal immune system may act as one of the major targets for the expression of pharmacological activity. The inner surface of the intestinal tract possesses a large area of mucosal membranes, and the intestinal epithelial cells sit at the interface between a lumen and a lymphocyte-rich lamina propria. The cross talk that occurs between these compartments serves to maintain intestinal homeostasis, and the cytokine network plays an important role in the cross talk. In this study, the effect of Hochuekkito (HET), one of Kampo medicines, on cytokine secretion of intestinal epithelial cells was investigated. When murine normal colonic epithelial cell-line MCE301 cells were stimulated with HET, the contents of granulocyte colony-stimulating factor (G-CSF) in the conditioned medium were significantly increased in dose- and time-dependent manners. The enhanced G-CSF gene transcription in MCE301 cells by the stimulation of HET was observed by RT-PCR. The enhanced G-CSF secretion by HET was also observed in C3H/HeJ mice-derived primary cultured colonic epithelial cells. When the HET was fractionated, only the polysaccharide fraction (F-5) enhanced the G-CSF secretion of MCE301 cells, and the activity of F-5 lost after the treatment of periodate that can degrade the carbohydrate moiety. These results suggest that HET enhances secretion of G-CSF from colonic epithelial cells and the polysaccharide is one of the active ingredients of HET. The enhanced G-CSF secretion by HET may partly contribute to the clinically observed various pharmacological activities of HET including immunomodulating activity.