Release Of Colony-stimulating Factor Research Articles

Inhaled Macrophage Apoptotic Bodies-Engineered Microparticle Enabling Construction of Pro-Regenerative Microenvironment to Fight Hypoxic Lung Injury in Mice.

Oxygen therapy cannot rescue local lung hypoxia in patients with severe respiratory failure. Here, an inhalable platform is reported for overcoming the aberrant hypoxia-induced immune changes and alveolar damage using camouflaged poly(lactic-co-glycolic) acid (PLGA) microparticles with macrophage apoptotic body membrane (cMAB). cMABs are preloaded with mitochondria-targeting superoxide dismutase/catalase nanocomplexes (NCs) and modified with pathology-responsive macrophage growth factor colony-stimulating factor (CSF) chains, which form a core-shell platform called C-cMAB/NC with efficient deposition in deeper alveoli and high affinity to alveolar epithelial cells (AECs) after CSF chains are cleaved by matrix metalloproteinase 9. Therefore, NCs can be effectively transported into mitochondria to inhibit inflammasome-mediated AECs damage in mouse models of hypoxic acute lung injury. Additionally, the at-site CSF release is sufficient to rescue circulating monocytes and macrophages and alter their phenotypes, maximizing synergetic effects of NCs on creating a pro-regenerative microenvironment that enables resolution of lung injury and inflammation. This inhalable platform may have applications to numerous inflammatory lung diseases.

Tumor-intrinsic NLRP3-HSP70-TLR4 axis drives premetastatic niche development and hyperprogression during anti-PD-1 immunotherapy.

The tumor-intrinsic NOD-, LRR- and pyrin domain-containing protein-3 (NLRP3) inflammasome-heat shock protein 70 (HSP70) signaling axis is triggered by CD8+ T cell cytotoxicity and contributes to the development of adaptive resistance to anti-programmed cell death protein 1 (PD-1) immunotherapy by recruiting granulocytic polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs) into the tumor microenvironment. Here, we demonstrate that the tumor NLRP3-HSP70 axis also drives the accumulation of PMN-MDSCs into distant lung tissues in a manner that depends on lung epithelial cell Toll-like receptor 4 (TLR4) signaling, establishing a premetastatic niche that supports disease hyperprogression in response to anti-PD-1 immunotherapy. Lung epithelial HSP70-TLR4 signaling induces the downstream Wnt5a-dependent release of granulocyte colony-stimulating factor (G-CSF) and C-X-C motif chemokine ligand 5 (CXCL5), thus promoting myeloid granulopoiesis and recruitment of PMN-MDSCs into pulmonary tissues. Treatment with anti-PD-1 immunotherapy enhanced the activation of this pathway through immunologic pressure and drove disease progression in the setting of Nlrp3 amplification. Genetic and pharmacologic inhibition of NLRP3 and HSP70 blocked PMN-MDSC accumulation in the lung in response to anti-PD-1 therapy and suppressed metastatic progression in preclinical models of melanoma and breast cancer. Elevated baseline concentrations of plasma HSP70 and evidence of NLRP3 signaling activity in tumor tissue specimens correlated with the development of disease hyperprogression and inferior survival in patients with stage IV melanoma undergoing anti-PD-1 immunotherapy. Together, this work describes a pathogenic mechanism underlying the phenomenon of disease hyperprogression in melanoma and offers candidate targets and markers capable of improving the management of patients with melanoma.

Regulatory T-cells inhibit microglia-induced pain hypersensitivity in female mice.

Peripheral nerve injury-induced neuropathic pain is a chronic and debilitating condition characterized by mechanical hypersensitivity. We previously identified microglial activation via release of colony-stimulating factor 1 (CSF1) from injured sensory neurons as a mechanism contributing to nerve injury-induced pain. Here, we show that intrathecal administration of CSF1, even in the absence of injury, is sufficient to induce pain behavior, but only in male mice. Transcriptional profiling and morphologic analyses after intrathecal CSF1 showed robust immune activation in male but not female microglia. CSF1 also induced marked expansion of lymphocytes within the spinal cord meninges, with preferential expansion of regulatory T-cells (Tregs) in female mice. Consistent with the hypothesis that Tregs actively suppress microglial activation in females, Treg deficient (Foxp3DTR) female mice showed increased CSF1-induced microglial activation and pain hypersensitivity equivalent to males. We conclude that sexual dimorphism in the contribution of microglia to pain results from Treg-mediated suppression of microglial activation and pain hypersensitivity in female mice.

MLKL promotes cellular differentiation in myeloid leukemia by facilitating the release of G-CSF

The blockade of cellular differentiation represents a hallmark of acute myeloid leukemia (AML), which is largely attributed to the dysfunction of lineage-specific transcription factors controlling cellular differentiation. However, alternative mechanisms of cellular differentiation programs in AML remain largely unexplored. Here we report that mixed lineage kinase domain-like protein (MLKL) contributes to the cellular differentiation of transformed hematopoietic progenitor cells in AML. Using gene-targeted mice, we show that MLKL facilitates the release of granulocyte colony-stimulating factor (G-CSF) by controlling membrane permeabilization in leukemic cells. Mlkl−/− hematopoietic stem and progenitor cells released reduced amounts of G-CSF while retaining their capacity for CSF3 (G-CSF) mRNA expression, G-CSF protein translation, and G-CSF receptor signaling. MLKL associates with early endosomes and controls G-CSF release from intracellular storage by plasma membrane pore formation, whereas cell death remained unaffected by loss of MLKL. Of note, MLKL expression was significantly reduced in AML patients, specifically in those with a poor-risk AML subtype. Our data provide evidence that MLKL controls myeloid differentiation in AML by controlling the release of G-CSF from leukemic progenitor cells.

Effectiveness of Mavrilimumab in Viral Infections Including SARS-CoV-2 Infection - A Brief Review.

Hyperinflammation and cytokine storm has been noted as a poor prognostic factor in patients with severe pneumonia related to coronavirus disease 2019 (COVID-19). In COVID-19, pathogenic myeloid cell overactivation is found to be a vital mediator of damage to tissues, hypercoagulability, and the cytokine storm. These cytokines unselectively infiltrate various tissues, such as the lungs and heart, and nervous system. This cytokine storm can hence cause multi-organ dysfunction and life-threatening complications. Mavrilimumab is a monoclonal antibody (mAb) that may be helpful in some cases with COVID-19. During an inflammation, Granulocyte-macrophage colony-stimulating factor (GM-CSF) release is crucial to driving both innate and adaptive immune responses. The GM-CSF immune response is triggered when an antigen attaches to the host cell and induces the signaling pathway. Mavrilimumab antagonizes the action of GM-CSF and decreases the hyperinflammation associated with pneumonia in COVID-19, therefore strengthening the rationale that mavrilimumab when added to the standard protocol of treatment could improve the clinical outcomes in COVID-19 patients, specifically those patients with pneumonia. With this review paper, we aim to demonstrate the inhibitory effect of mavrilimumab on cytokine storms in patients with COVID-19 by reviewing published clinical trials and emphasize the importance of extensive future trials.

Phenotypic differences in early outgrowth angiogenic cells based on in vitro cultivation.

Bone marrow-derived early outgrowth cells play an important role in endothelial repair. In vitro isolation techniques have identified two distinct morphological early outgrowth cell populations, but it is still unknown whether they present some functional phenotypic differences. Accordingly, the aim of the present study was to determine whether there are phenotypic differences in cellular function between two putative early outgrowth cells in culture. Peripheral blood samples were collected from 18 healthy adults. Thereafter, mononuclear cells were isolated by Ficoll density-gradient centrifugation and plated on 6-well plates coated with human fibronectin. After 2 and 7days, respectively, non-adherent cells (NAC) and adherent cells (AC) underwent functional assays in order to measure the migratory capacity (Boyden chamber), angiogenic growth factor release (ELISA) and apoptosis (TUNEL). Migration to both VEGF (517 ± 74 vs. 273 ± 74AU) and SDF-1 (517 ± 68 vs. 232 ± 68AU) were approximately twofold higher (P < 0.05) in the NAC when compared to AC. Release of angiogenic factors, granulocyte colony-stimulating and hepatocyte growth factor, were not different between cell types. Apoptotic response to staurosporine was significantly lower in NAC (20 ± 32 vs. 125 ± 32%). In summary, NAC and AC demonstrated functional phenotypic differences in migratory capacity and apoptotic susceptibility, which makes it difficult to compare these two early outgrowth cell populations in literature.

Cortisol limits selected actions of synthetic glucocorticoids in the airway epithelium.

Cortisol, a physiologic glucocorticoid (GC), is essential for growth and differentiation of the airway epithelium. Epithelial function influences inflammation in chronic respiratory diseases. Synthetic GCs, including inhaled corticosteroids, exert anti-inflammatory effects in airway epithelium by transactivation of genes and by inhibition of proinflammatory cytokine release. We examined the effect of cortisol on the actions of synthetic GCs in the airway epithelium, demonstrating that cortisol acts like a partial agonist at the GC receptor (GR), limiting GC-induced GR-dependent transcription in the BEAS-2B human bronchial epithelial cell line. Cortisol also limited the inhibition of granulocyte macrophage colony-stimulating factor release by synthetic GCs in TNF-α-activated BEAS-2B cells. The relevance of these findings is supported by observations on tracheal epithelium obtained from mice treated for 5 d with systemic GC, showing limitations in selected GC effects, including inhibition of IL-6. Moreover, gene transactivation by synthetic GCs was compromised by standard air-liquid interface (ALI) growth medium cortisol concentration (1.4 μM) in the ALI-differentiated organotypic culture of primary human airway epithelial cells. These findings suggest that endogenous corticosteroids may limit certain actions of synthetic pharmacological GCs and contribute to GC insensitivity, particularly when corticosteroid levels are elevated by stress.-Prodanovic, D., Keenan, C. R., Langenbach, S., Li, M., Chen, Q., Lew, M. J., Stewart, A. G. Cortisol limits selected actions of synthetic glucocorticoids in the airway epithelium.

Altered expression and signalling of EP2 receptor in nasal polyps of AERD patients: role in inflammation and remodelling

Down-regulation of the E-prostanoid (EP)2 receptor has been reported in aspirin exacerbated respiratory disease (AERD). We aimed to evaluate the expression and activation of EP receptors in AERD and their role in prostaglandin (PG) E2 signalling. Samples were obtained from nasal mucosa of control subjects (NM-C, n=7) and from nasal polyps of AERD patients (NP-AERD, n=7). Expression of EP1-4 was assessed at baseline. Fibroblasts were stimulated with receptor agonists to measure cAMP levels, cell proliferation and granulocyte-macrophage colony-stimulating factor (GM-CSF) release. NM-C and NP-AERD samples and fibroblasts expressed EP2, EP3 and EP4 at baseline. Lower expression of EP2 and higher expression of EP4 was observed in NP-AERD compared with NM-C. Stimulation with PGE2 and butaprost caused a higher increase in cAMP in NM-C than in NP-AERD. On the contrary, CAY10598 produced a higher production of cAMP in NP-AERD compared with NM-C. The anti-proliferative effect of PGE2 and butaprost was lower in NP-AERD than in NM-C fibroblasts. Similarly, the capacity of PGE2 and butaprost to inhibit GM-CSF release was lower in NP-AERD than in NM-C. The altered expression of EP2 in AERD may contribute to reduce the capacity of PGE2 to mediate anti-proliferative and anti-inflammatory effects.

Altered expression and signalling of EP2 receptor in nasal polyps of AERD patients: role in inflammation and remodelling.

Down-regulation of the E-prostanoid (EP)2 receptor has been reported in aspirin exacerbated respiratory disease (AERD). We aimed to evaluate the expression and activation of EP receptors in AERD and their role in prostaglandin (PG) E2 signalling. Samples were obtained from nasal mucosa of control subjects (NM-C, n=7) and from nasal polyps of AERD patients (NP-AERD, n=7). Expression of EP1-4 was assessed at baseline. Fibroblasts were stimulated with receptor agonists to measure cAMP levels, cell proliferation and granulocyte-macrophage colony-stimulating factor (GM-CSF) release. NM-C and NP-AERD samples and fibroblasts expressed EP2, EP3 and EP4 at baseline. Lower expression of EP2 and higher expression of EP4 was observed in NP-AERD compared with NM-C. Stimulation with PGE2 and butaprost caused a higher increase in cAMP in NM-C than in NP-AERD. On the contrary, CAY10598 produced a higher production of cAMP in NP-AERD compared with NM-C. The anti-proliferative effect of PGE2 and butaprost was lower in NP-AERD than in NM-C fibroblasts. Similarly, the capacity of PGE2 and butaprost to inhibit GM-CSF release was lower in NP-AERD than in NM-C. The altered expression of EP2 in AERD may contribute to reduce the capacity of PGE2 to mediate anti-proliferative and anti-inflammatory effects.

House Dust Mite Allergens and the Induction of Monocyte Interleukin 1β Production That Triggers an IκBζ-Dependent Granulocyte Macrophage Colony-Stimulating Factor Release from Human Lung Epithelial Cells.

Asthma is a chronic lung disease characterized by inflammation centered upon bronchial epithelium. House dust mite is one of the most common respiratory allergens that trigger exacerbations of asthma. IκBζ (gene NFKBIZ) is a recently recognized member of the NF-κB family that can be induced in mononuclear phagocytes and lung epithelial cells and has been shown to play a prominent role in epithelial cell function. We therefore analyzed the role of IκBζ in regulating lung epithelial cell cytokine responses to house dust mite mix (HDM). We found that human bronchial epithelial cells express IκBζ and release IL-6 and granulocyte macrophage colony-stimulating factor (GMCSF) when cocultured with human monocytes and HDM. This response is blocked in the presence of IL-1 receptor antagonist (IL-1Ra), indicating that it is IL-1 mediated. Neither HDM-stimulated macrophages nor dendritic cells release IL-1β and subsequently induce cytokine release from the bronchial epithelial cells. Rhodobacter sphaeroides LPS (RS-LPS), a TLR4 antagonist, blocks the ability of HDM to induce IκBζ and release GMCSF from epithelial cells cocultured with monocytes. Additionally, human bronchial epithelial cells show no induction of IκBζ or cytokine responses to direct HDM stimulation. Finally, NFKBIZ small interfering RNA-mediated knockdown in the bronchial epithelial cells suppresses the release of IL-1-induced IL-6 and GMCSF. Our findings indicate a possible role for monocyte recruitment and lung epithelial cell IκBζ in mediating asthma associated inflammation. Thus, IκBζ, IL-1Ra, and RS-LPS deserve future study as potential modulators of house dust mite-induced asthma.

Controlled Release of Granulocyte Colony-Stimulating Factor Enhances Osteoconductive and Biodegradable Properties of Beta-Tricalcium Phosphate in a Rat Calvarial Defect Model

Autologous bone grafts remain the gold standard for the treatment of congenital craniofacial disorders; however, there are potential problems including donor site morbidity and limitations to the amount of bone that can be harvested. Recent studies suggest that granulocyte colony-stimulating factor (G-CSF) promotes fracture healing or osteogenesis. The purpose of the present study was to investigate whether topically applied G-CSF can stimulate the osteoconductive properties of beta-tricalcium phosphate (β-TCP) in a rat calvarial defect model. A total of 27 calvarial defects 5 mm in diameter were randomly divided into nine groups, which were treated with various combinations of a β-TCP disc and G-CSF in solution form or controlled release system using gelatin hydrogel. Histologic and histomorphometric analyses were performed at eight weeks postoperatively. The controlled release of low-dose (1 μg and 5 μg) G-CSF significantly enhanced new bone formation when combined with a β-TCP disc. Moreover, administration of 5 μg G-CSF using a controlled release system significantly promoted the biodegradable properties of β-TCP. In conclusion, the controlled release of 5 μg G-CSF significantly enhanced the osteoconductive and biodegradable properties of β-TCP. The combination of G-CSF slow-release and β-TCP is a novel and promising approach for treating pediatric craniofacial bone defects.

Thioredoxin-1 Protects against Neutrophilic Inflammation and Emphysema Progression in a Mouse Model of Chronic Obstructive Pulmonary Disease Exacerbation

BackgroundExacerbations of chronic obstructive pulmonary disease (COPD) are characterized by acute enhancement of airway neutrophilic inflammation under oxidative stress and can be involved in emphysema progression. However, pharmacotherapy against the neutrophilic inflammation and emphysema progression associated with exacerbation has not been established. Thioredoxin-1 has anti-oxidative and anti-inflammatory properties and it can ameliorate neutrophilic inflammation through anti-chemotactic effects and prevent cigarette smoke (CS)-induced emphysema. We aimed to determine whether thioredoxin-1 can suppress neutrophilic inflammation and emphysema progression in a mouse model of COPD exacerbation and if so, to reveal the underlying mechanisms.ResultsMice were exposed to CS and then challenged with polyinosine-polycytidylic acid [poly(I:C)], an agonist for virus-induced innate immunity. Airway neutrophilic inflammation, oxidative stress and lung apoptosis were enhanced in smoke-sensitive C57Bl/6, but not in smoke-resistant NZW mice. Exposure to CS and poly(I:C) challenge accelerated emphysema progression in C57Bl/6 mice. Thioredoxin-1 suppressed neutrophilic inflammation and emphysema progression. Poly(I:C) caused early neutrophilic inflammation through keratinocyte-derived chemokine and granulocyte-macrophage colony-stimulating factor (GM-CSF) release in the lung exposed to CS. Late neutrophilic inflammation was caused by persistent GM-CSF release, which thioredoxin-1 ameliorated. Thioredoxin-1 enhanced pulmonary mRNA expression of MAP kinase phosphatase 1 (MKP-1), and the suppressive effects of thioredoxin-1 on prolonged GM-CSF release and late neutrophilic inflammation disappeared by inhibiting MKP-1.ConclusionUsing a mouse model of COPD exacerbation, we demonstrated that thioredoxin-1 ameliorated neutrophilic inflammation by suppressing GM-CSF release, which prevented emphysema progression. Our findings deepen understanding of the mechanisms underlying the regulation of neutrophilic inflammation by thioredoxin-1 and indicate that thioredoxin-1 could have potential as a drug to counteract COPD exacerbation.

Tissue-engineered oral mucosa to study radiotherapy-induced oral mucositis

Purpose: Oral mucositis is a severe and often dose-limiting side-effect of cancer therapy that occurs in patients receiving radiotherapy for head and neck cancers. Although radiation-induced effects on keratinocytes have been studied, little is known about its effect on fibroblasts or endothelial cells or, more importantly, when all these cells are combined in an engineered oral mucosal model.Materials and methods: Monolayer cultures of normal oral keratinocytes, normal oral fibroblasts, human dermal microvascular endothelial cells or tissue-engineered oral mucosa (TEOM) were exposed to 20 Gy irradiation. Cell damage and cytokine release was measured for 72 h for monolayer cultures and for up to 21 d for TEOM.Results: Compared to non-irradiated cells, the viability of all monolayer and co-cultures was significantly reduced 72 h post-irradiation while levels of secreted interleukin IL-6 and CXCL8 were increased. The viability of irradiated TEOM models was significantly reduced compared to controls at all time-points. Histologically, irradiated TEOM displayed thinner epithelium, increased apoptosis and more extensive damage than non-irradiated models. IL-6, CXCL8 and granulocyte macrophage colony-stimulating factor release was reduced whereas IL-1α levels were increased in irradiated TEOM models compared to controls.Conclusions: TEOM models comprising of mixed cell populations may prove useful in examining the pathobiology of radiation-induced mucositis.

Cellular response within the periodontal ligament on application of orthodontic forces

During application of controlled orthodontic force on teeth, remodeling of the periodontal ligament (PDL) and the alveolar bone takes place. Orthodontic forces induce a multifaceted bone remodeling response. Osteoclasts responsible for bone resorption are mainly derived from the macrophages and osteoblasts are produced by proliferations of the cells of the periodontal ligament. Orthodontic force produces local alterations in vascularity, as well as cellular and extracellular matrix reorganization, leading to the synthesis and release of various neurotransmitters, cytokines, growth factors, colony-stimulating factors, and metabolites of arachidonic acid. Although many studies have been reported in the orthodontic and related scientific literature, research is constantly being done in this field resulting in numerous current updates in the biology of tooth movement, in response to orthodontic force. Therefore, the aim of this review is to describe the mechanical and biological processes taking place at the cellular level during orthodontic tooth movement.

Mouse Precision-Cut Liver Slices as an ex Vivo Model To Study Idiosyncratic Drug-Induced Liver Injury

Idiosyncratic drug-induced liver injury (IDILI) has been the top reason for withdrawing drugs from the market or for black box warnings. IDILI may arise from the interaction of a drug's reactive metabolite with a mild inflammation that renders the liver more sensitive to injury resulting in increased toxicity (inflammatory stress hypothesis). Aiming to develop a robust ex vivo screening method to study inflammatory stress-related IDILI mechanisms and to find biomarkers that can detect or predict IDILI, mouse precision-cut liver slices (mPCLS) were coincubated for 24 h with IDILI-related drugs and lipopolysaccharide. Lipopolysaccharide exacerbated ketoconazole (15 μM) and clozapine (45 μM) toxicity but not their non-IDILI-related comparators, voriconazole (1500 μM) and olanzapine (45 μM). However, the other IDILI-related drugs tested [diclofenac (200 μM), carbamazepine (400 μM), and troglitazone (30 μM)] did not cause synergistic toxicity with lipopolysaccharide after 24 h of incubation. Lipopolysaccharide further decreased the reduced glutathione levels caused by ketoconazole or clozapine in mPCLS after 24 h of incubation, which was not the case for the other drugs. Lipopolysaccharide significantly increased nitric oxide (NO), cytokine, and chemokine release into the mPCLS media, while the treatment with the drugs alone did not cause any substantial change. All seven drugs drastically reduced lipopolysaccharide-induced NO production. Interestingly, only ketoconazole and clozapine increased the lipopolysaccharide-induced granulocyte colony-stimulating factor (G-CSF) and granulocyte-macrophage colony-stimulating factor (GM-CSF) release. Pilot experiments showed that diclofenac and troglitazone, but not carbamazepine, demonstrated synergistic toxicity with lipopolysaccharide after a longer incubation of 48 h in mPCLS. In conclusion, we have developed an ex vivo model to detect inflammatory stress-related liver toxicity and identified ketoconazole, clozapine, troglitazone, and diclofenac as drugs that showed synergistic toxicity with lipopolysaccharide. Reduced glutathione, G-CSF, and GM-CSF were identified to be potential biomarkers for IDILI-inducing drugs mediated by inflammatory stress, and mPCLS appear to be a promising screening tool to further unravel the mechanism of IDILI.

Orally bioavailable small-molecule inhibitor of transcription factor Stat3 regresses human breast and lung cancer xenografts

Computer-aided lead optimization derives a unique, orally bioavailable inhibitor of the signal transducer and activator of transcription (Stat)3 Src homology 2 domain. BP-1-102 binds Stat3 with an affinity (K(D)) of 504 nM, blocks Stat3-phospho-tyrosine (pTyr) peptide interactions and Stat3 activation at 4-6.8 μM, and selectively inhibits growth, survival, migration, and invasion of Stat3-dependent tumor cells. BP-1-102-mediated inhibition of aberrantly active Stat3 in tumor cells suppresses the expression of c-Myc, Cyclin D1, Bcl-xL, Survivin, VEGF, and Krüppel-like factor 8, which is identified as a Stat3 target gene that promotes Stat3-mediated breast tumor cell migration and invasion. Treatment of breast cancer cells with BP-1-102 further blocks Stat3-NF-κB cross-talk, the release of granulocyte colony-stimulating factor, soluble intercellular adhesion molecule 1, macrophage migration-inhibitory factor/glycosylation-inhibiting factor, interleukin 1 receptor antagonist, and serine protease inhibitor protein 1, and the phosphorylation of focal adhesion kinase and paxillin, while enhancing E-cadherin expression. Intravenous or oral gavage delivery of BP-1-102 furnishes micromolar or microgram levels in tumor tissues and inhibits growth of human breast and lung tumor xenografts.

Novel supramolecular hydrogel/micelle composite for co-delivery of anticancer drug and growth factor

Novel supramolecular hydrogel/micelle composites were designed for the co-encapsulation and prolonged release of camptothecin (CPT) and granulocyte colony-stimulating factor (G-CSF). For this purpose, heparin-conjugated Pluronic F-127 (Hep-F-127) was synthesized by a click reaction and then used to self-assemble the micelles with their hydrophobic cores loaded with CPT and hydrophilic shells complexed with G-CSF. By mixing α-cyclodextrin (α-CD) and CPT-loaded Hep-F-127 micelle/G-CSF complexes in an aqueous system, the supramolecular hydrogel/micelle composite with good injectability could be formed under mild conditions. For the co-encapsulated CPT and G-CSF, they could maintain their biological activity and exhibit a more prolonged release when compared to CPT-loaded Hep-F-127 micelles/G-CSF complexes. Moreover, the gelation properties and drug release profiles could by tuned by α-CD amount.

Biological response at the cellular level within the periodontal ligament on application of orthodontic force - An update.

Orthodontic force elicits a biological response in the tissues surrounding the teeth, resulting in remodeling of the periodontal ligament and the alveolar bone. The force-induced tissue strain result in reorganization of both cellular and extracellular matrix, besides producing changes in the local vascularity. This in turn leads to the synthesis and release of various neurotransmitters, arachidonic acid, growth factors, metabolites, cytokines, colony-stimulating factors, and enzymes like cathepsin K, matrix metalloproteinases, and aspartate aminotransferase. Despite the availability of many studies in the orthodontic and related scientific literature, a concise integration of all data is still lacking. Such a consolidation of the rapidly accumulating scientific information should help in understanding the biological processes that underlie the phenomenon of tooth movement in response to mechanical loading. Therefore, the aim of this review was to describe the biological processes taking place at the molecular level on application of orthodontic force and to provide an update of the current literature.

Lipopolysaccharide-enhanced transcellular transport of HIV-1 across the blood-brain barrier is mediated by luminal microvessel IL-6 and GM-CSF

Elevated levels of cytokines/chemokines contribute to increased neuroinvasion of human immunodeficiency virus type 1 (HIV-1). Previous work showed that lipopolysaccharide (LPS), which is present in the plasma of patients with HIV-1, enhanced transcellular transport of HIV-1 across the blood-brain barrier (BBB) through the activation of p38 mitogen-activated protein kinase (MAPK) signaling in brain microvascular endothelial cells (BMECs). Here, we found that LPS (100 μg/mL, 4 hr) selectively increased interleukin (IL)-6 and granulocyte-macrophage colony-stimulating factor (GM-CSF) release from BMECs. The enhancement of HIV-1 transport induced by luminal LPS was neutralized by treatment with luminal, but not with abluminal, antibodies to IL-6 and GM-CSF without affecting paracellular permeability as measured by transendothelial electrical resistance (TEER). Luminal, but not abluminal, IL-6 or GM-CSF also increased HIV-1 transport. U0126 (MAPK kinase (MEK)1/2 inhibitor) and SB203580 (p38 MAPK inhibitor) decreased the LPS-enhanced release of IL-6 and GM-CSF. These results show that p44/42 and p38 MAPK signaling pathways mediate the LPS-enhanced release of IL-6 and GM-CSF. These cytokines, in turn, act at the luminal surface of the BMEC to enhance the transcellular transport of HIV-1 independently of actions on paracellular permeability.

Preparation and characterisation of PLGA microspheres for sustained release of recombinant human granulocyte colony-stimulating factor

The purpose of this research was to develop a sustained micosphere for recombinant human granulocyte colony-stimulating factor (RHG-CSF). RHG-CSF was first incorporated into glassy sodium hyaluronate (HA) particle according to the freezing-induced phase separation method previously reported by the authors&apos; group. Once G-CSF was incorporated in the glassy HA particles, it gained resistance to organic solvents. The glassy HA particle containing G-CSF was subsequently encapsulated into polylactic-co-glycolic acid (PLGA) matrix to get HA-PLGA composite microspheres by the solid-in-oil-in-water multiple emulsion technique. The novel glassy HA particle and composite microsphere were characterised by scanning electron microscopy, particle and size distribution, size-exclusion HPLC. The in vitro release data indicate that continuous and sustained release profile was achieved for more than 30 days compared with microspheres prepared by the traditional water-in-oil-in-water method. Also the bioassay was assessed by proliferative ability of NSF-60 cell line and the result suggests that the bioactivity was preserved well in the process of formulation steps and in vitro release.