Granulocyte-macrophage Stimulating Factor Research Articles

The role of TGF-β in the differentiation and lung specification of murine type 1 conventional dendritic cells.

Abstract Lung-resident type 1 conventional dendritic cells (cDC1s) are critical for initiating immune responses against foreign respiratory viruses and endogenous assaults like cancer cells. Importantly, the cDCs of each tissue display unique phenotypes and functions dictated by the environment they populate. However, our understanding of the factors that regulate cDC1 development and function in the lung is minimal. The cytokines, FMS-like tyrosine kinase 3 ligand (FLT3L), and granulocyte-macrophage stimulating factor (GM-CSF) are essential for the development of tissue-resident cDC1, but in in vitro systems, these factors are insufficient to generate cDC1s with a lung-specific phenotype. RNAseq analysis of lung cDC1 identified a clear enrichment in genes associated with transforming growth factor beta (TGF-β) signaling, a factor also known to be enriched in the airspaces of the lung. TGF-β has been previously reported to maintain DC quiescence in the lung, however, our data suggested it may also play a role in differentiation and lung specification of these cells. Based on this, I hypothesized that adding TGF-β to in vitro bone marrow (BM) cultures alongside established cytokines FLT3L and GM-CSF would generate cDC1s phenotypically and functionally similar to in vivo lung cDC1s. The addition of TGF-β, but not GM-CSF, to optimized FLT3L-BMDC cultures resulted in development of cDC1 which highly resemble lung cDC1. The development of a high throughput in vitro system that differentiates functional lung cDC1s will not only inform the in vivo factors required for development of these cells but also provides a useful platform for interrogation of lung cDC1 function and a stepping-off point to begin models for human lung cDC1 production and study Supported by grants from the University of Washington PREP program NIH (R25) and the Fred Hutchinson Cancer Center Diversity, Equity, and Inclusion Student Fellowship

Neutrophil-dependent Mitochondrial DNA Release Associated With Extracellular Trap Formation in Inflammatory Bowel Disease.

Inflammatory bowel disease (IBD) is associated with increased circulating damage-associated molecular patterns, in particular, the highly pro-inflammatory mitochondrial DNA (mtDNA). Here, we study the importance of blood neutrophils in mtDNA release via neutrophil extracellular trap (NET) formation and mitochondrial NETosis, where neutrophils specifically expulse mtDNA as potential targetable biological pathways. We investigated the roles of A23187 (a known NET stimulant), granulocyte macrophage stimulating factor, lipopolysaccharide (LPS), and human IBD plasma in their ability to induce NET formation, mitochondrial NETosis, mtDNA, and total DNA release from human blood neutrophils; and the evidence for increased NET formation in IBD. We demonstrated that NET formation resulted in significant DNA (P < .0001) and mtDNA release (P < .0001) with long DNA fragments (>1000 base pairs) with NETs containing high levels of mtDNA. Using previously described invitro conditions for mitochondrial NETosis, granulocyte macrophage stimulating factor+ LPS triggered neutrophil mtDNA release at lower levels but not NETosis. LPS alone can trigger neutrophilic DNA release without NET formation. Heterologous coculture with plasma from patients with active IBD (vs remission [n= 6/group]) were not associated with significantly higher levels of NETs and mtDNA release. During coculture with active IBD plasma (vs remission), citrullinated histone 3 (CitH3) (a NETs biomarker) levels were significantly lower (P < .001). Similarly, CitH3 levels were lower in stool supernatants of patients with active IBD vs remission (n= 19/12, P= .0001). Stool CitH3 negatively correlates with stool calprotectin, a biomarker for gut inflammation (r=-0.47, P= .03). Hence, although blood neutrophils remain an important source of circulating mtDNA with defined mechanisms for release via NET formation and during neutrophil activation, our data do not support excessive systemic NET formation as a dominant underpinning pathobiological process in IBD.

Soluble CD163 is produced by monocyte-derived and alveolar macrophages, and is not associated with the severity of idiopathic pulmonary fibrosis.

The soluble form of the membrane hemoglobin scavenger receptor CD163 (sCD163), released by shedding, is a strong marker for macrophage activation. Serum sCD163 levels rise in several acute inflammatory states and some fibrosing diseases. Monocyte-derived macrophages (MoDM) differentiated by macrophage colony-stimulating factor (M-MoDM) contribute to the pathophysiology of idiopathic pulmonary fibrosis (IPF), an irreversible and rapidly fatal interstitial lung disease. Since M-MoDM express high membrane CD163 levels, we thus postulated that sCD163 could be a relevant biomarker for macrophage activation in IPF. We found that M-MoDM constitutively released higher amounts of sCD163 (49.5 ± 24.5 ng/ml) than monocytes (0.45 ± 0.32 ng/ml) or MoDM differentiated with granulocyte macrophage-stimulating factor (2.24 ± 0.98 ng/ml). The basal production of sCD163 by M-MoDM was increased following stimulation with lipopolysaccharide (123.4 ± 54.9 ng/ml) or ATP (168.9 ± 41.8 ng/ml). The sCD163 release was controlled by metalloproteases but not through ADAM17 activation. Moreover, CD163-positive macrophages and sCD163 were detected in pulmonary tissues and alveolar fluids of Caucasian patients with IPF, respectively. IPF alveolar macrophages constitutively secreted sCD163 amounts (67.6 ± 44.6 ng/µg RNA) which were significantly higher than those released by alveolar macrophages isolated from controls (19.2 ± 7.6 ng/µg RNA) or patients with other interstitial lung disease (31.5 ± 16.6 ng/µg RNA). However, the concentrations of sCD163 in blood serum collected from 155 patients with IPF did not correlate with the severity of their disease. In conclusion, our results show that M-MoDM constituted a pertinent model to study the regulation of sCD163 production. Yet, serum sCD163 values could not provide a prognostic biomarker for IPF in our cohort.

Abstract 2219: OnxoVEXmGM-CSF promotes systemic response to PD-L1 /PD-1 blockade in multiple mouse syngeneic tumor models

Abstract Inhibition of the immune-checkpoint axis that involves PD-L1/PD-1 has improved responses and outcomes for certain cancer patients, but there remains unmet need as only a fraction of patients respond to these therapies. Talimogene laherparepvec (T-VEC) is an FDA-approved, first-in-class oncolytic immunotherapy based on a modified herpes simplex virus type 1 (HSV-1) designed to selectively replicate in tumors and produce granulocyte-macrophage stimulating factor (GM-CSF) to enhance a tumor-antigen specific adaptive immune response. Intratumoral treatment with T-VEC has been shown to promote an inflammatory tumor microenvironment both preclinically and clinically. Combining T-VEC with immune checkpoint inhibitors is of high interest to potentially broaden and deepen the clinical responses in checkpoint-resistant tumors. In the current study, we evaluated the efficacy of OncoVEXmGM-CSF (an HSV modified like T-VEC, except that it produces murine GM-CSF) in combination with anti-PD-1/PD-L1 treatment in multiple syngeneic mouse tumor models. Bilateral tumor models were used, where only one tumor was treated with OncoVEXmGM-CSF (representing the local oncolytic effect), allowing the evaluation of systemic abscopal effect in the uninjected contralateral tumors. OncoVEXmGM-CSF in combination with anti-PD-L1/PD-1 enhanced tumor growth inhibition in both treated and contralateral tumors in the A20 and MC38 syngeneic models and overcame anti-PD-L1 resistance in the CT26 model. The combination treatment also led to a significant increase in median overall survival compared to either agent as a monotherapy. In addition, tumor antigen epitopes were identified by combining exome sequencing and MHC/HLA-binding prediction algorithms. Antigen-specific T cell response was measured in an IFN-γ ELISPOT assay using splenocytes from treated mice. OncoVEXmGM-CSF induced and /or enhanced systemic T cell responses directed against both tumor neoantigens and tumor-associated antigens. Together, these data reveal that OncoVEXmGM-CSF treatment can cause direct tumor lysis along with the potentiation of an adaptive, systemic T cell-mediated anti-tumor immune response that can be enhanced by the addition of PD-L1/PD-1. Our study provides a strong rationale for the ongoing clinical evaluation of the combination of T-VEC and PD1-/PD-L1-targeted therapy in cancer patients. Citation Format: Keegan Cooke, Juan Estrada, Petia Mitchell, Jinghiu Zhan, Pedro J. Beltran, Jing Qing, Jude Canon. OnxoVEXmGM-CSF promotes systemic response to PD-L1 /PD-1 blockade in multiple mouse syngeneic tumor models [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 2219.

Evaluation of soluble expression of recombinant granulocyte macrophage stimulating factor (rGM-CSF) by three different E. coli strains.

Background and purpose:Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a cytokine with a wide range of therapeutic applications although expression of GM-CSF in Escherichia coli (E. coli) usually leads to formation of insoluble aggregates mostly lack biological activity. The aim of this study was to compare the soluble expression level of GM-CSF in three E. coli strains, BL21 (DE3), SHuffle® T7 and Origami™ 2 (DE3).Experimental approach:The effect of different temperatures and inducer concentrations on soluble expression of GM-CSF was evaluated. The soluble GM-CSF was subjected to endotoxin removal and purification using nickel-nitrilotriacetic acid (Ni-NTA) affinity chromatography, ultrafiltration. The biological activity of produced GM-CSF was evaluated based on its growth promotion effect on TF-1 cell lines by MTT assay method.Findings / Results:A significant improvement of the soluble yield of GM-CSF (about 30% of GM-CSF was expressed as soluble proteins) was observed when protein expression was induced at 30 °C with 0.5 mM isopropyl β- d-1-thiogalactopyranoside (IPTG) in E. coli Shuffle T7. The soluble GM-CSF with a high purity up to 95 % and specific activity of 1.25 × 104 IU/μg was obtained.Conclusion and implications:The proposed strategy here can be used to improve the soluble expression of other hard-to-express proteins with similar structural properties (i.e., containing disulfide binds or cysteine).

The antidepressant effects of GM-CSF are mediated by the reduction of TLR4/NF-\u0138B-induced IDO expression

BackgroundIndoleamine 2, 3-dioxygenase 1 (IDO) is responsible for the progression of the kynurenine pathway. This pathway has been implicated in the pathophysiology of inflammation-induced depression in which conventional antidepressants are not effective. It has been reported that granulocyte-macrophage stimulating factor (GM-CSF) could interfere with the induction of IDO in septic patients. We hypothesized that GM-CSF could exert antidepressant effects through IDO downregulation in a model for acute inflammation-induced depression.MethodsTo produce the model, lipopolysaccharide (LPS) (0.83 mg/kg) was administered intraperitoneally to mice. It has been well documented that LPS mediates IDO overexpression through TLR4/NF-ĸB signaling. In the treatment group, mice received GM-CSF (30 μg/kg, i.p.) thirty minutes prior to LPS injection. A validated selective serotonin reuptake inhibitor, fluoxetine (30 mg/kg i.p.), was also administered to an experimental group 30 min prior to LPS. Depressive-like behaviors were evaluated based on the duration of immobility in the forced swim test. To confirm that GM-CSF interferes with IDO induction in LPS treated mice, real-time PCR was used to quantify IDO mRNA expression. Furthermore, in order to study whether GM-CSF inhibits the TLR4/NF-ĸB signaling pathway, we measured levels ofpNF-ĸB and TLR4 by western blotting.ResultsGM-CSF demonstrated significant antidepressant activity in the presence of LPS on immobility (p < .001) and latency (p = .010) times in the forced swim test. In contrast, fluoxetine did not show any antidepressant activity on either immobility (p = .918) or latency (p = .566) times. Furthermore, GM-CSF inhibited the increase in IDO mRNA (p = .032) and protein (p = .016) expression as a result of LPS administration. A similar trend was observed for TLR4 (p = .042) and pNF-ĸB (p = .026) expression as both proteins showed reduced expression levels in the GM-CSF-pretreated group compared to the untreated (LPS) group.ConclusionOur results propose a promising antidepressant effect for GM-CSF possibly through the downregulation of IDO expression. This remedying effect of GM-CSF could be attributed to decreased amounts of TLR4 and active NF-ĸB in the treated mice.

Elevated inflammatory cytokines in aqueous cytokine profile in HIV-1 infected patients with cataracts in Uganda

BackgroundCataracts occur earlier among HIV-infected adults and this is attributed to various intraocular inflammatory processes that result in early degeneration. In this study we purposed to investigate whether HIV infected individuals with cataracts develop heightened intraocular inflammatory processes compared to their HIV negative counterparts by determining the concentration of 8 cytokines in the aqueous humour of HIV-positive adults with cataracts and their HIV-negative counterparts.MethodsA cross-sectional study was conducted among consecutive adults with cataracts that were operated in an ophthalmology surgical camp in western Uganda. We determined levels of Granulocyte macrophage stimulating factor (GM-CSF), interleukin 6 (IL-6), interleukin 8 (IL-8), tumour necrotic factor alpha (TNF-a), interferon gamma (IFN-g), interleukin 4 (IL-4), interleukin 2 (IL-2), and interleukin (IL-10) in the aqueous fluid using a multiplexed cytokine analysis.Data was entered in the SPSS version 10 and analyzed using STATA statistical software version 7.0. Categorical and continuous variables were compared using the χ2 test, Fisher’s exact test and the Student’s t-test. Bonferroni correction was used to cater for multiple comparison of p values for the various cytokines.ResultsThe 50 adults that underwent cataract surgery were outdoor peasants with similar exposure hours to UV radiation. The HIV-positive patients were younger {median age 43 years (SD 11.741)} compared to the HIV -negative patients {median age 66.5 years (SD 21.4)}. The mean CD4+ T cell count of the HIV-positive patients was 161 cells /mm3, and 12(48%) had started anti-retroviral therapy (ART). Pro inflammatory cytokines, GM-CSF, IL-8 and IL-10 were significantly higher among HIV-positive individuals (p = 0.001, 0.030, < 0.001 respectively). HIV-positive individuals on ART also showed significantly higher levels of GM-CSF, IL-8 and IL − 10 (p = 0.002, 0.021, < 0.001 respectively). TNF-a and IL-4 were significantly higher among those with a CD4+ T cell count greater than 200cells/mm3 compared to those with CD4+ T cell count less than 200 cells/mm3 (p = 0.022, 0.032 respectively).ConclusionCataracts among HIV-positive adults were associated with higher intraocular inflammation relative to the healthy elderly individuals with cataracts. There is need to explore the potential role of intra-ocular anti-inflammatory agents in the management of cataracts among HIV positive patients.

High yield primary microglial cultures using granulocyte macrophage-colony stimulating factor from embryonic murine cerebral cortical tissue

BackgroundMicroglia play vital roles in neurotrophic support and modulating immune or inflammatory responses to pathogens or damage/stressors during disease. This study describes the ability to establish large numbers of microglia from embryonic tissues with the addition of granulocyte-macrophage stimulating factor (GM-CSF) and characterizes their similarities to adult microglia examined ex vivo as well as their responses to inflammatory mediators. MethodMicroglia were seeded from a primary embryonic mixed cortical suspension with the addition of GM-CSF. Microglial expression of CD45, CD11b, CD11c, MHC class I and II, CD40, CD80, and CD86 was analyzed by flow cytometry and compared to those isolated using different culture methods and to the BV-2 cell line. GM-CSF microglia immunoreactivity and cytokine production was examined in response to lipopolysaccharide (LPS) and interferon-γ (IFN-γ). ResultsOur results demonstrate GM-CSF addition during microglial culture yields higher cell numbers with greater purity than conventionally cultured primary microglia. We found that the expression of immune markers by GM-CSF microglia more closely resemble adult microglia than other methods or an immortalized BV-2 cell line. Primary differences amongst the different groups were reflected in their levels of CD39, CD86 and MHC class I expression. GM-CSF microglia produce CCL2, tumor necrosis factor-α, IL-6 and IL-10 following exposure to LPS and alter costimulatory marker expression in response to LPS or IFN-γ. Notably, GM-CSF microglia were often more responsive than the commonly used BV-2 cell line which produced negligible IL-10. ConclusionGM-CSF cultured microglia closely model the phenotype of adult microglia examined ex vivo. GM-CSF microglia are robust in their responses to inflammatory stimuli, altering immune markers including Iba-1 and expressing an array of cytokines characteristic of both pro-inflammatory and reparative processes. Consequently, the addition of GM-CSF for the culturing of primary microglia serves as a valuable method to increase the potential for studying microglial function ex vivo.

Erratum to: Granulocyte-macrophage stimulating factor (GM-CSF) increases circulating dendritic cells but does not abrogate suppression of adaptive cellular immunity in patients with metastatic colorectal cancer receiving chemotherapy

Advanced cancer and chemotherapy are both associated with immune system suppression. We initiated a clinical trial in patients receiving chemotherapy for metastatic colorectal cancer to determine if administration of GM-CSF in this setting was immunostimulatory.Between June, 2003 and January, 2007, 20 patients were enrolled in a clinical trial (NCT00257322) in which they received 500 ug GM-CSF daily for 4 days starting 24 hours after each chemotherapy cycle. There were no toxicities or adverse events reported. Blood was obtained before chemotherapy/GM-CSF administration and 24 hours following the final dose of GM-CSF and evaluated for circulating dendritic cells and adaptive immune cellular subsets by flow cytometry. Peripheral blood mononuclear cell (PBMC) expression of γ-interferon and T-bet transcription factor (Tbx21) by quantitative real-time PCR was performed as a measure of Th1 adaptive cellular immunity. Pre- and post-treatment (i.e., chemotherapy and GM-CSF) samples were evaluable for 16 patients, ranging from 1 to 5 cycles (median 3 cycles, 6 biologic sample time points). Dendritic cells were defined as lineage (-) and MHC class II high (+).73% of patients had significant increases in circulating dendritic cells of ~3x for the overall group (5.8% to 13.6%, p = 0.02) and ~5x excluding non-responders (3.2% to 14.5%, p < 0.001). This effect was sustained over multiple cycles for approximately half of the responders, but tachyphylaxis over subsequent chemotherapy cycles was noted for the remainder. Treatment also led to a significant reduction in the proportion of circulating regulatory T-cells (Treg; p = 0.0042). PBMC Tbx21 levels declined by 75% following each chemotherapy cycle despite administration of GM-CSF (p = 0.02). PBMC γ-interferon expression, however was unchanged.This clinical trial confirms the suppressive effects of chemotherapy on Th1 cellular immunity in patients with metastatic colorectal cancer but demonstrates that mid-cycle administration of GM-CSF can significantly increase the proportion of circulating dendritic cells. As the role of dendritic cells in anti-tumor immunity becomes better defined, GM-CSF administration may provide a non-toxic intervention to augment this arm of the immune system for cancer patients receiving cytotoxic therapy.ClinicalTrials.gov: NCT00257322.

Mosquitocidal Immune Response in BALB/c Mice Is Enhanced When Anopheles gambiae Mucin-1 cDNA Is Co-Administered with Interleukin-12 cDNA

The midgut of the malaria - transmitting mosquito, Anopheles gambiae, can be targeted by vaccine-induced host immune factors that kill the mosquito after it ingests immunized host blood. The An. gambiae mucin 1 protein (AgMuc1) is expressed on the mosquito midgut where it likely functions in protecting the midgut epithelium from its own secreted digestive enzymes, toxic substances and pathogenic microbes taken in with the blood meal. Immunization of mice with plasmid containing the AgMuc1 gene has been shown to induce mosquitocidal immune responses. In this paper, we co-immunized mice with AgMuc1 cDNA and plasmid containing Murine granulocyte-macrophage stimulating factor (GM-CSF) or Interleukin 12 (IL-12) cytokine cDNA in order to further potentiate the mosquitocidal immune response and better define the nature of this mosquitocidal immunity. While co-immunization with GM-CSF cDNA failed to increase anti-mosquito immunity (Chisq = 3.3 on 1 degree of freedom, p = 0.068), a significantly enhanced mosquitocidal effect was observed from mice co-immunized with AgMuc1 and IL-12 cDNA (Chisq = 39.1 on I degree of freedom, p = 4.06e-10). Furthermore, the cumulative survival of the blood fed mosquitoes surviving to day 7 in the AgMuc1/IL-12 co-immunized group highly correlated negatively with the anti-mucin IgG1 antibody subtype levels (Pearson correlation coefficient r = -0.782) suggesting that the mosquitocidal immunity induced by AgMuc1 cDNA immunization could be IgG1 antibody subtype mediated.

Smoke exposure of human macrophages reduces HDAC3 activity, resulting in enhanced inflammatory cytokine production

Chronic obstructive pulmonary disease (COPD) is a debilitating condition resulting from exposure to pollutants such as cigarette smoke. Pulmonary macrophages secrete a plethora of inflammatory mediators that are increased in the lungs of COPD patients, but whether this phenotype results directly from smoke exposure remains unknown. Using an in vitro model for alveolar macrophages (AM) derived from human peripheral blood monocytes with granulocyte-macrophage stimulating factor (GM-MØ), we analyzed the mechanistic connection between cigarette smoke exposure and histone deacetylase (HDAC) regulation, hypothesized to be a contributing factor in COPD pathophysiology. Here we show that acute smoke exposure inhibits HDAC enzymatic activity in GM-MØ. Analysis of mRNA and total cellular proteins for expression of class I (1, 2, 3 and 8), class II (4, 5, 6, 7, 9, 10), and class IV (11) HDAC revealed no effect of smoke exposure, whereas nuclear HDAC3 protein content was reduced. To better understand the physiological significance of reduced HDAC3 activity, we utilized siRNA to knockdown HDAC1, 2 and 3 individually. Interestingly, siRNA-mediated reduction of HDAC3 resulted in increased production of IL8 and IL1β in response to LPS stimulation, while HDAC2 knockdown had no effect on either cytokine. Lower nuclear content of HDAC3 in the context of equivalent total HDAC protein levels following smoke exposure may reflect increased nuclear export of HDAC3, allowing increased nuclear factor kappa b (NF-κB ) driven cytokine expression that can contribute to inflammation.

Granulocyte-macrophage stimulating factor (GM-CSF) increases circulating dendritic cells but does not abrogate suppression of adaptive cellular immunity in patients with metastatic colorectal cancer receiving chemotherapy

BackgroundAdvanced cancer and chemotherapy are both associated with immune system suppression. We initiated a clinical trial in patients receiving chemotherapy for metastatic colorectal cancer to determine if administration of GM-CSF in this setting was immunostimulatory.MethodsBetween June, 2003 and January, 2007, 20 patients were enrolled in a clinical trial (NCT00257322) in which they received 500 ug GM-CSF daily for 4 days starting 24 hours after each chemotherapy cycle. There were no toxicities or adverse events reported. Blood was obtained before chemotherapy/GM-CSF administration and 24 hours following the final dose of GM-CSF and evaluated for circulating dendritic cells and adaptive immune cellular subsets by flow cytometry. Peripheral blood mononuclear cell (PBMC) expression of γ-interferon and T-bet transcription factor (Tbx21) by quantitative real-time PCR was performed as a measure of Th1 adaptive cellular immunity. Pre- and post-treatment (i.e., chemotherapy and GM-CSF) samples were evaluable for 16 patients, ranging from 1 to 5 cycles (median 3 cycles, 6 biologic sample time points). Dendritic cells were defined as lineage (-) and MHC class II high (+).Results73% of patients had significant increases in circulating dendritic cells of ~3x for the overall group (5.8% to 13.6%, p = 0.02) and ~5x excluding non-responders (3.2% to 14.5%, p < 0.001). This effect was sustained over multiple cycles for approximately half of the responders, but tachyphylaxis over subsequent chemotherapy cycles was noted for the remainder. Treatment also led to a significant reduction in the proportion of circulating regulatory T-cells (Treg; p = 0.0042). PBMC Tbx21 levels declined by 75% following each chemotherapy cycle despite administration of GM-CSF (p = 0.02). PBMC γ-interferon expression, however was unchanged.ConclusionsThis clinical trial confirms the suppressive effects of chemotherapy on Th1 cellular immunity in patients with metastatic colorectal cancer but demonstrates that mid-cycle administration of GM-CSF can significantly increase the proportion of circulating dendritic cells. As the role of dendritic cells in anti-tumor immunity becomes better defined, GM-CSF administration may provide a non-toxic intervention to augment this arm of the immune system for cancer patients receiving cytotoxic therapy.Trial RegistrationClinicalTrials.gov: NCT00257322

Cytokine Profiles in Asthma Families Depend on Age and Phenotype

BackgroundCirculating cytokine patterns may be relevant for the diagnosis of asthma, for the discrimination of certain phenotypes, and prognostic factors for exacerbation of disease.Methodology/Principal FindingsIn this study we investigated serum samples from 944 individuals of 218 asthma-affected families by a multiplex, microsphere based system detecting at high sensitivity eleven asthma associated mediators: eotaxin (CCL11), granulocyte macrophage stimulating factor (GM-CSF), interferon gamma (IFNγ), interleukin-4 (IL-4), IL-5, IL-8, IL-10, IL-12 (p40), IL-13, IL-17 and tumor necrosis factor alpha (TNFα). Single cytokine levels were largely similar between asthmatic and healthy individuals when analysing asthma as single disease entity. Regulatory differences between parental and pediatric asthma were reflected by six of the eleven mediators analyzed (eotaxin, IL-4, IL-5, IL-10, IL-12, TNFα). IL-12 (p40) and IL-5 were the best predictor for extrinsic asthma in children with an increased odds ratio of 2.85 and 1.96 per log pg/ml increase (IL-12 (p40): 1.2–6.8, p = 0.019, and IL-5: 1.2–2.5, p = 0.025). Frequent asthma attacks in children are associated with elevated IL-5 serum levels (p = 0.013). Cytokine patterns seem to be individually balanced in both, healthy and diseased adults and children, with various cytokines correlating among each other (IL-17 and IFNγ (rs = 0.67), IL-4 and IL-5 (rs = 0.55), IFNγ and GM-CSF (rs = 0.54)).Conclusion/SignificanceOur data support mainly an age- but also an asthma phenotype-dependent systemic immune regulation.

Interleukin-17 Is Required for T Helper 1 Cell Immunity and Host Resistance to the Intracellular Pathogen Francisella tularensis

The importance of T helper type 1 (Th1) cell immunity in host resistance to the intracellular bacterium Francisella tularensis is well established. However, the relative roles of interleukin (IL)-12-Th1 and IL-23-Th17 cell responses in immunity to F. tularensis have not been studied. The IL-23-Th17 cell pathway is critical for protective immunity against extracellular bacterial infections. In contrast, the IL-23-Th17 cell pathway is dispensable for protection against intracellular pathogens such as Mycobacteria. Here we show that the IL-23-Th17 pathway regulates the IL-12-Th1 cell pathway and was required for protective immunity against F.tularensis live vaccine strain. We show that IL-17A, but not IL-17F or IL-22, induced IL-12 production in dendritic cells and mediated Th1 responses. Furthermore, we show that IL-17A also induced IL-12 and interferon-gamma production in macrophages and mediated bacterial killing. Together, these findings illustrate a biological function for IL-17A in regulating IL-12-Th1 cell immunity and host responses to an intracellular pathogen.

Myeloid-derived suppressor cells in mammary tumor progression in FVB Neu transgenic mice.

Female mice transgenic for the rat proto-oncogene c-erb-B2, under control of the mouse mammary tumor virus (MMTV) promoter (neuN), spontaneously develop metastatic mammary carcinomas. The development of these mammary tumors is associated with increased number of GR-1(+)CD11b(+) myeloid derived suppressor cells (MDSCs) in the peripheral blood (PB), spleen and tumor. We report a complex relationship between tumor growth, MDSCs and immune regulatory molecules in non-mutated neu transgenic mice on a FVB background (FVB-neuN). The first and second tumors in FVB-neuN mice develop at a median of 265 (147-579) and 329 (161-523) days, respectively, resulting in a median survival time (MST) of 432 (201 to >500) days. During tumor growth, significantly increased number of MDSCs is observed in the PB and spleen, as well as, in infiltrating the mammary tumors. Our results demonstrate a direct correlation between tumor size and the number of MDSCs infiltrating the tumor and an inverse relationship between the frequency of CD4(+) T-cells and MDSCs in the spleen. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) assessment of enzyme and cytokine transcript levels in the spleen, tumor, tumor-infiltrating non-parenchymal cells (NPCs) and mammary glands revealed a significant increase in transcript levels from grossly normal mammary glands and tumor-infiltrating NPCs during tumor progression. Tumor NPCs, as compared to spleen cells from wild-type (w/t) mice, expressed significantly higher levels of arginase-1 (ARG-1), nitric oxide synthase (NOS-2), vascular endothelial growth factor (VEGF-A) and significantly lower levels of interferon (IFN)-gamma, interleukin (IL)-2 and fms-like tyrosine kinase-3 ligand (Flt3L) transcript levels. Transcript levels in the spleens of tumor-bearing (TB) mice also differed from normal mice, although to a lesser extent than transcript levels from tumor-infiltrating NPCs. Furthermore, both spleen cells and NPCs from TB mice, but not control mice, suppressed alloantigen responses by syngeneic control spleen cells. Correlative studies revealed that the number of MDSCs in the spleen was directly associated with granulocyte colony stimulating factor (G-CSF) transcript levels in the spleen; while the number of MDSCs in the tumors was directly correlated with splenic granulocyte macrophage stimulating factor (GM-CSF) transcript levels, tumor volume and tumor cell number. Together our results support a role for MDSCs in tumor initiation and progressive, T-cell depression and loss of function provide evidence which support multiple mechanisms of MDSC expansion in a site-dependent manner.

Chemotherapy with Granulocyte Colony Stimulating Factor (G-CSF) Alone Versus Granulocyte Colony Stimulating Factor (G-CSF) Plus Granulocyte-Macrophage Stimulating Factor (GM-CSF) for Hematopoietic Progenitor Cell Mobilization in Patients with Relapsed Non-Hodgkin's Lymphomas (NHLs).

Both G-CSF and GM-CSF (alone or in combination) may be used for mobilization of hematopoietic progenitor cells in patients undergoing autologous stem cell transplantation (ASCT). It has been suggested that GM-CSF use during mobilization may impact graft composition and therefore clinical outcomes.METHODS: We prospectively evaluated patients ≤ 70 years old with relapsed CD20+ NHL who were candidates for ASCT. Additional eligibility criteria included adequate marrow and organ function. Patients with history of pelvic radiation, > 3 prior chemoregimens or > 6 cycles of fludarabine chemotherapy were excluded. Patients recieved chemotherapy with ifosfamide 3.33 g/m2 daily × 3 days, etoposide 150 mg/m2 × 6 doses and rituximab (375 mg/m2 on day 1 and 1 g/m2 on day 8). Using a Bayesian adaptive randomization based on treatment outcomes, patient's were randomized to receive G-CSF 12 μg/kg/d (Group G) or G-CSF 12 μg/kg/d plus GM-CSF 500 μg/d (Group G/GM). We assumed that the success rate for each treatment arm had a β prior distribution with mean 0.90 and variance 0.03. Cytokines started 24 hours after completion of chemotherapy and continued until completion of apheresis.RESULTS: Forty-three patients were randomized to Group G and 41 patients to Group G/GM. In each arm 1 patient withdrew consent after randomization. Baseline characteristics were similar in the 2 groups (Table 1). Both regimens were equally well tolerated. Data are presented as intent to treat analysis. Thirty-nine patients (90.7%) in Group G and 35 patients (85.4%) in Group G/GM collected ≥ 4 × 106 CD34+ cells/kg. The probability that Group G has a higher success rate than Group G/GM is 0.778. The median CD34+ cell dose collected was 10.3 × 106/kg (range, 0.1–59) and 7.5 × 106/kg (range, 0.7–73) in Groups G and G/GM respectively (P=NS). A median of 2 apheresis procedures were required in both arms. Seventy-three patients have undergone ASCT. After a median follow up time of 14.5 months (range, 0.6–38.5) in Group G and 14.0 months (range, 1.1–39.9) in Group G/GM, the 3 year PFS is 75% (95% CI 57.9–99.4) and 77% (95% CI 65–91.5) respectively (P=0.41).CONCLUSION: Our study does not support the hypothesis that using G-CSF plus GM-CSF versus G-CSF alone for progenitor cell mobilization alters graft composition in a way that impacts clinical outcomes after ASCT for NHLs.Baseline Patient CharacteristicsG-CSF, N (%)G-CSF + GM-CSF, N (%)43 (51)41 (49)AGE<394 (9.3)3 (7.3)40–5929 (57.4)26 (63.5)>5910 (23.2)12 (29.3)GENDER (Male/Female)29/14 (67.4/32.6)24/17 (58.5/41.5)HISTOLOGYLow grade4 (9.3)7 (17.1)Intermediate grade39 (90.7)34 (82.9)ANN ARBOR STAGE >I18 (41.9)18 (43.9)LDH>Normal*15 (34.9)11 (27.5)*Missing data 1 patient [Display omitted]

Overlapping human leukocyte antigen class I/II binding peptide vaccine for the treatment of patients with stage IV melanoma

MPS160 (GRAMLGTHTMEVTV) is a glycoprotein 100-derived melanoma peptide that contains overlapping human leukemic antigen A2-, DR53-, and DQw6-restricted T-cell epitopes. In preclinical testing, MPS160 demonstrated superior immunization and antitumor activity. In this report, the authors present the results from a clinical trial that evaluated the safety and immunologic efficacy of the MPS160 vaccine in patients with metastatic melanoma. Patients with stage IV melanoma were randomized to 1 of 3 treatment arms: 1) MPS160 in incomplete Freund adjuvant (Montanide ISA-51); 2) MPS160 in Montanide ISA-51 with 75 microg of granulocyte-macrophage-stimulating factor (GM-CSF); or 3) MPS160 in Montanide ISA-51 with 100 microg of GM-CSF. Vaccines were administered every 3 weeks until patients developed disease progression or severe toxicity. Patients were aged >or=18 years with metastatic melanoma and a good performance status. Exclusion criteria included pregnancy/nursing, brain metastases, and ongoing chemotherapy. Immunologic efficacy was ascertained by using tetramer and functional analysis of peripheral blood lymphocytes. None of the 28 patients exhibited objective tumor responses or severe toxicities. Four patients remained progression free for >or=100 days. Immunologic analysis was available for 21 patients. Laboratory data demonstrated 1) increased frequency of vaccine-specific, nonfunctional cytotoxic T lymphocytes in 10 patients; 2) no differences in immunization efficacy among the treatment arms; and 3) evidence of systemic cytokine/immune dysfunction. Clinically, the MPS160 vaccine was ineffective. Phenotypic (tetramer) evidence of immunization was ineffective functionally and most likely was caused by global immune dysfunction, as illustrated by abnormal cytokine profiles in peripheral blood. In this report, the authors discuss possible implications of the current results on future cancer vaccine studies.

Interleukin-2 (IL-2) and granulocyte-macrophage stimulating factor (GM-CSF) for treatment of relapse after allogeneic stem cell transplant (ASCT)

Interleukin-2 (IL-2) and granulocyte-macrophage stimulating factor (GM-CSF) for treatment of relapse after allogeneic stem cell transplant (ASCT)

Phenotypic and functional characteristics of dendritic cells derived from human peripheral blood monocytes

This study is aimed at developing a simple and easy way to generate dendritic cells (DCs) from human peripheral blood monocytes (PBMCs) in vitro. PBMCs were isolated directly from white blood cell rather than whole blood and purified by patching methods (collecting the attached cell and removing the suspension cell). DCs were then generated by culturing PBMCs for six days with 30 ng/ml recombinant human granulocyte-macrophage stimulating factor (rhGM-CSF) and 20 ng/ml recombinant human interleukin-4 (rhIL-4) in vitro. On the sixth day, TNF-alpha (TNFalpha) 30 ng/ml was added into some DC cultures, which were then incubated for two additional days. The morphology was monitored by light microscopy and transmission electronic microscopy, and the phenotypes were determined by flow cytometry. Autologous mixed leukocyte reactions (MLR) were used to characterize DC function after TNFalpha or lipopolysaccharide (LPS) stimulations for 24 h. After six days of culture, the monocytes developed significant dendritic morphology and a portion of cells expressed CD1a, CD80 and CD86, features of DCs. TNFalpha treatment induced DCs maturation and up-regulation of CD80, CD86 and CD83. Autologous MLR demonstrated that these DCs possess potent T-cell stimulatory capacity. This study developed a simple and easy way to generate DCs from PBMCs exposed to rhGM-CSF and rhIL-4. The DCs produced by this method acquired morphologic and antigenic characteristics of DCs.

The rationale behind a vaccine based on multiple HIV antigens

The viral diversity of HIV-1 is likely to require a vaccine strategy that induces broad cellular and humoral anti-HIV-1 immunity. Our strategy is based on multiple HIV-1 DNA immunogens together with adjuvant recombinant granulocyte-macrophage stimulating factor. This article describes pre-clinical and clinical work preceding the initiation of clinical HIV-1 phase I/II trials.