Granulocyte-macrophage colony-stimulating factor （GM-CSF） and T-cell responses： what we do and don＇t know

Granulocyte-macrophage colony-stimulating factor （GM-CSF） is an important hematopoietic growth factor and immune modulator. GM-CSF also has profound effects on the functional activities of various circulating leukocytes. It is produced by a variety of cell types including T cells, macrophages, endothelial cells and fibroblasts upon receiving immune stimuli. Although GM-CSF is produced locally, it can act in a paracrine fashion to recruit circulating neutrophils, monocytes and lymphocytes to enhance their functions in host defense. Recent intensive investigations are centered on the application of GM-CSF as an immune adjuvant for its ability to increase dendritic cell （DC） maturation and function as well as macrophage activity. It is used clinically to treat neutropenia in cancer patients undergoing chemotherapy, in AIDS patients during therapy, and in patients after bone marrow transplantation. Interestingly, the hematopoietic system of GM-CSF-deficient mice appears to be normal; the most significant changes are in some specific T cell responses. Although molecular cloning of GM-CSF was carried out using cDNA library oft cells and it is well known that the T cells produce GM-CSF after activation, there is a lack of systematic investigation of this cytokine in production by T cells and its effect on T cell function. In this article, we will focus mainly on the immunobiology of GM-CSF in T cells.

Granulocyte-macrophage colony-stimulating factor protects mice against hepatocellular carcinoma by ameliorating intestinal dysbiosis and attenuating inflammation

BACKGROUND Hepatocellular carcinoma(HCC)is the third leading cause of cancer mortality worldwide.The gut microbiota can help maintain healthy metabolism and immunity.Granulocyte-macrophage colony-stimulating factor(GM-CSF)is a critical factor in promoting health and homeostasis;it promotes intestinal immunity,stimulates bone marrow precursors to generate macrophage colonies,and enhances the antibacterial and antitumor activity of circulating monocytes.As such,GM-CSF may protect against HCC development by regulating immunity as well as intestinal microecology.AIM To investigate the impact of GM-CSF on the gut microbiome and metabolic characteristics of HCC.METHODS Thirty-six male BALB/c nude mice were divided into three groups:Control(n=10),HCC(n=13),and HCC+GM-CSF(GM-CSF overexpression,n=13).We utilized HCC cells to establish orthotopic transplantation tumor models of HCC with normal and over-expressing GM-CSF.Liver injury,immune inflammatory function and intestinal barrier function were evaluated.The fecal microbiome and metabolome were studied using 16S rRNA absolute quantification sequencing and gas chromatography-mass spectrometry.RESULTS GM-CSF overexpression significantly affected the gut microbiome of mice with HCC and resulted in a high abundance of organisms of the genera Roseburia,Blautia and Butyricimonass,along with a significant reduction in Prevotella,Parabacteroides,Anaerotruncus,Streptococcus,Clostridium,and Mucispirillum.Likewise,GM-CSF overexpression resulted in a substantial increase in fecal biotin and oleic acid levels,along with a prominent decrease in the fecal succinic acid,adenosine,fumaric acid,lipoic acid,and maleic acid levels.Correlation analysis revealed that the intestinal microbiota and fecal metabolites induced by GM-CSF were primarily involved in pathways related to reducing the inflammatory response,biotin metabolism,and intestinal barrier dysfunction.CONCLUSION GM-CSF can protect against HCC development by regulating immunity and modulating the abundance of specific intestinal microorganisms and their metabolites.This study provides new insights into the therapeutic approaches for HCC.

Granulocyte-macrophage colony-stimulating factor-transfected bone marrow stromal cells for the treatment of ischemic stroke

Adult, male, Sprague-Dawley rats were injected with granulocyte-macrophage colony-stimulating factor-transfected bone marrow stromal cells （GM-CSF-BMSCs） into the ischemic boundary zone at 24 hours after onset of middle cerebral artery occlusion. Results showed reduced infarct volume, decreased number of apoptotic cells, improved neurological functions, increased angiogenic factor expression, and increased vascular density in the ischemic boundary zone in rats that underwent GM-CSF-BMSCs transplantation compared with the BMSCs group. Experimental findings suggested that GM-CSF-BMSCs could serve as a potential therapeutic strategy for ischemic stroke and are superior to BMSCs alone.

CONSTRUCTION OF EUKARYOTIC EXPRESSION VECTOR WITH GRANULOCYTE-MACROPHAGE COLONY-STIMULATING FACTOR GENE

Objective: To construct the eukaryotic expression vector that express human granulocyte-macrophage colony-stimulating factor (hGM-CSF) gene for making highly express in mammalian cells. Methods: Extract totally RNA from the induced human fetal lung (HFL) cell line. HGM-CSF cDNA was obtained by reverse transcription-polymerase chain reaction (RT-PCR), and then directionally subcloned into the HindIII and EcoRI site on the pcDNA3.1 plasmid, which was controlled by the CMV promoter, to form the recombinant expressing vector pcDNA3.1-GM-CSF. Results: The PCR amplification was identified and the sequence was analyzed, the results showed that hGM-CSF was properly inserted into the vector and the sequence was correct.

Granulocyte-macrophage colony stimulating factor improves cardiac function in rabbits following myocardial infarction

Objective: To investigate the therapeutic potency of recombinant human Granulocyte-Macrophage Colony-Stimulating Factor (GM-CSF) in a rabbit myocardial infarction model. Methods: A myocardial infarction was created by the ligation of the major ventricular branch of the left coronary artery in rabbits. After myocardial infarction, the animals were randomly assigned to GM-CSF treatment group, untreated groups and sham-operated group. The rabbits of the treated group were injected into GM-CSF by subcutaneous administration, 10 μg/kg/day, once a day for 5 days. The untreated and sham-operated group received a equal saline in the same manner as treated group. Six weeks later echocardiography and haemodynamic assessment were undertaken to assesse cardiac function. The size of the infarct region of the heart were also studied. Results: The untreated group exhibited significant higher left ventricle end-diastolic pressure, higher central venous pressure, and with significant lower mean blood pressure, lower peak first derivative of left ventricle pressure (dP/dt) than the sham group. Also, Rabbits in untreated group display significant systolic dysfunction shown by the decreased ejection fraction, diastolic dysfunction shown by increasing in the ratio of E wave to A wave (E/A), and display left ventricle enlargement. However, GS-CSF singnificantly prevented heart dysfunction, left ventricle enlargement, and reduced infarct size in treatment group. Conclusion: Administration GM-CSF after cardiac infarction can improve heart function. These findings indicate the technique may be a novel and simple therapeutic method for ischemic myocardium.

EFFECTS OF GRANULOCYTE-MACROPHAGE COLONY STIMULATING FACTOR GENE ENCODED VACCINIA VIRUS VECTOR ON MURINE PULMONARY METASTATIC MELANOMA

A recombinant vaccinia virus expressing murine granulocyte-macrophage colony-stimulating factor (VVGM-CSF) was tested for its antitumor activity.Murine pulmonary metastasis was established by injecting 20×10~5 B16F10 melanoma cells into the tail vein of C57BL/6 mice. Three days after B16F10 inoculation,WGM-CSF or VVTK, a thymidine kinase gene deficient control vaccinia virus, were injected intraperitoneally twice weekly for 2 weeks. Two weeks later, the mice were sacrificed and pulmonary metastasis fool counted.The results demonstrated that VVGM-CSF treatment significantly decreased the number of pulmonary metastasis and prolonged the survival time of tumorbearing mice. Cytotoxic and phagocytic activities of the peritoncal macrophages were found to be markedly elevated in mice treated with WGM-CSF. Nitric oxide released from the macrophages was also found to be increased. These data, together with our other results,strongly demonstrated that continuous secretion of GMCSF and activation of macrophages might pal-tially explain the therapeutic effects of VVGM-CSF on murine pulmonary metastasis.

Granulocyte-macrophage colony-stimulating factor and interleukin 4 induce the malignant transformation of the bone marrow- derived human adult mesenchymal stem cells

Background The purpose of the study was to examine the effects of granulocyte-macrophage colony-stimulating factor （GM-CSF） and interleukin 4 （IL-4） on the bone-marrow-derived human adult mesenchymal stem cells （hMSCs）. Methods The hMSCs were isolated and cultured with GM-CSF and IL-4 for a period of one month. A single colony of transformed cells was then isoloated and their phenotype was characterized by morphology, surface marker expression, and in vivo tumorigenesis.Results After one month culture, the transformed mesenchymal cells exhibited the morphology and phenotype similar to those of tumor cells, and also caused multiple fast growing lung deposits when it was injected into immunodeficient mice.Conclusion Cytokines-driven malignant transformation of hMSCs may be a useful model for studying signaling pathways initiating malignant transformation of hMSC.

Clinical Study of Recombinant Human Granulocyte-Macrophage Colony-Stimulating Factor on Chemotherapy-Induced Leukopenia.

We have studied the efficacy and safery of recombinant human granulocyte-macrophate colony-stimulating factor

Serum profiles of circulating granulocyte-macrophage colony-stimulating factor in acute myocardial infarction and relation with post-infarction left ventricular function

Accumulating evidence indicates that inflammation plays an important role in cardiac repairing and remodeling after acute myocardial infarction （AMI）, process of which is mediated by a cytokine reaction cascade. 1 Granulocytemacrophage colony-stimulating factor （GM-CSF） is a cytokine, which belongs to the family of haemopoietic cell colony-stimulating factor and regulates the proliferation and differentiation of myeloid progenitor cells. In addition to its growthpromoting effects, this pro-inflammation cytokine stimulates the function of mature neutrophils, monocytes and eosinophils, including regulation of leukocyte adhesion, augmentation of surface antigen expression, superoxide anion generation, enhancement or induction of other cytokine production.

Stem cells as an option for the treatment of COVID-19

The application of stem cells is among the many strategies currently available for the treatment of multiple diseases.Stem cells are characterized as undifferentiated cells that have the ability to differentiate towards multiple lineages and selfrenewal,among other attributes.Since the first umbilical cord stem cell transplant for the treatment of Fanconi anemia,the use of stem cells for the treatment of multiple diseases,including coronavirus disease 2019,has increased,showing promising results that require evaluation through research studies that include a longer follow-up time.Therefore,the main objective of this Letter is to provide an update on the use of stem cells in the treatment of severe acute respiratory syndrome coronavirus 2,as well as identify the main challenges and limitations presented by this type of therapy.

An open-label multiyear study of sargramostim-treated Parkinson’s disease patients examining drug safety,tolerability,and immune biomarkers from limited case numbers

Background The clinical utility and safety of sargramostim has previously been reported in cancer,acute radiation syndrome,autoimmune disease,inflammatory conditions,and Alzheimer’s disease.The safety,tolerability,and mecha-nisms of action in Parkinson’s disease(PD)during extended use has not been evaluated.Methods As a primary goal,safety and tolerability was assessed in five PD patients treated with sargramostim(Leukine®,granulocyte-macrophage colony-stimulating factor)for 33 months.Secondary goals included numbers of CD4+T cells and monocytes and motor functions.Hematologic,metabolic,immune,and neurological evaluations were assessed during a 5-day on,2-day off therapeutic regimen given at 3μg/kg.After 2 years,drug use was discon-tinued for 3 months.This was then followed by an additional 6 months of treatment.Results Sargramostim-associated adverse events included injection-site reactions,elevated total white cell counts,and bone pain.On drug,blood analyses and metabolic panels revealed no untoward side effects linked to long-term treatment.Unified Parkinson’s Disease Rating Scale scores remained stable throughout the study while regulatory T cell number and function were increased.In the initial 6 months of treatment,transcriptomic and proteomic mono-cyte tests demonstrated autophagy and sirtuin signaling.This finding paralleled anti-inflammatory and antioxidant activities within both the adaptive and innate immune profile arms.Conclusions Taken together,the data affirmed long-term safety as well as immune and anti-inflammatory responses reflecting clinical stability in PD under the sargramostim treatment.Confirmation in larger patient populations is planned in a future phase II evaluation.

Analysis of the GM-CSF and GM-CSF/IL-3/IL-5 receptor common beta chain in a patient with pulmonary alveolar proteinosis

Objective To investigate the expression of the granulocyte-macrophage colony-stimulating factor (GM-CSF) and GM-CSF/IL-3/IL-5 receptor common beta chain (βc receptor) in an adult patient with idiopathic pulmonary alveolar proteinosis (PAP), so as to demonstrate the possible association of the GM-CSF and βc receptor with the pathogenesis of human PAP.Methods The GM-CSF levels were measured with a commercial ELISA kit (sensitivity 5?pg/ml) and the βc receptor expression on the cell surface was detected by flow cytometry analysis. Reverse transcription-polymerase chain reaction (RT-PCR) analysis was employed to detect the expression of the GM-CSF mRNA and the βc receptor mRNA in peripheral blood mononuclear cells and alveolar macrophages. The entire coding regions of the GM-CSF cDNA and the βc receptor cDNA were sequenced by the Sanger dideoxy-mediated chain termination method to detect possible mutations.Results The patient with PAP failed to release the GM-CSF protein either from circulating mononuclear cells or from alveolar macrophages. The expression of the GM-CSF mRNA was normal after the stimulation of lipopolysaccharide, whereas a point mutation at position 382 of the GM-CSF cDNA from 'T' to 'C' was revealed by cDNA sequencing, which caused a change in amino acid 117 of the protein from isoleucine to threonine. The βc receptor expression on the cell surface was normal, and the βc receptor mRNA expression and the sequence of the entire coding region of the βc receptor were also normal.Conclusions The decreased GM-CSF production is associated with the pathogenesis of human PAP. A point mutation of the GM-CSF cDNA may contribute to the decreased GM-CSF production in our adult PAP patient. The mutation of the βc receptor in some of paediatric patients with PAP may not be a common problem in adult patients.