A simple method for human peripheral blood monocyte isolation

TRPV4 is expressed by enteric glia and muscularis macrophages of the colon but does not play a prominent role in colonic motility

Background

Mechanosensation is an important trigger of physiological processes in the gastrointestinal tract. Aberrant responses to mechanical input are associated with digestive disorders, including visceral hypersensitivity. Transient Receptor Potential Vanilloid 4 (TRPV4) is a mechanosensory ion channel with proposed roles in visceral afferent signaling, intestinal inflammation, and gut motility. While TRPV4 is a potential therapeutic target for digestive disease, current mechanistic understanding of how TRPV4 may influence gut function is limited by inconsistent reports of TRPV4 expression and distribution.

Methods

In this study we profiled functional expression of TRPV4 using Ca2+ imaging of wholemount preparations of the mouse, monkey, and human intestine in combination with immunofluorescent labeling for established cellular markers. The involvement of TRPV4 in colonic motility was assessed in vitro using videomapping and contraction assays.

Results

The TRPV4 agonist GSK1016790A evoked Ca2+ signaling in muscularis macrophages, enteric glia, and endothelial cells. TRPV4 specificity was confirmed using TRPV4 KO mouse tissue or antagonist pre-treatment. Calcium responses were not detected in other cell types required for neuromuscular signaling including enteric neurons, interstitial cells of Cajal, PDGFRα+ cells, and intestinal smooth muscle. TRPV4 activation led to rapid Ca2+ responses by a subpopulation of glial cells, followed by sustained Ca2+ signaling throughout the enteric glial network. Propagation of these waves was suppressed by inhibition of gap junctions or Ca2+ release from intracellular stores. Coordinated glial signaling in response to GSK1016790A was also disrupted in acute TNBS colitis. The involvement of TRPV4 in the initiation and propagation of colonic motility patterns was examined in vitro.

Conclusions

We reveal a previously unappreciated role for TRPV4 in the initiation of distension-evoked colonic motility. These observations provide new insights into the functional role of TRPV4 activation in the gut, with important implications for how TRPV4 may influence critical processes including inflammatory signaling and motility.

Cellular models in autoinflammatory disease research

Systemic autoinflammatory diseases are a heterogeneous group of rare genetic disorders caused by dysregulation of the innate immune system. Understanding the complex mechanisms underlying these conditions is critical for developing effective treatments. Cellular models are essential for identifying new conditions and studying their pathogenesis. Traditionally, these studies have used primary cells and cell lines of disease-relevant cell types, although newer induced pluripotent stem cell (iPSC)-based models might have unique advantages. In this review, we discuss the three cellular models used in autoinflammatory disease research, their strengths and weaknesses, and their applications to inform future research in the field.

Accelerated blood clearance of PEGylated nanoparticles induced by PEG-based pharmaceutical excipients

PEGylated nanomedicines have been extensively developed and applied to cancer therapy. However, the antitumor efficacy of these nanoparticles is hampered by the accelerated blood clearance (ABC) effect caused by anti-PEG antibodies in vivo. There is still limited understanding about the cause of pre-existing anti-PEG antibodies in the human body. Herein, we discovered that PEG-based pharmaceutical excipients, commonly used in clinical and daily settings, could induce anti-PEG antibodies in vivo and lead to considerable potential clinical impacts on pharmacokinetics and pharmacodynamics of PEGylated nanoparticles. Specifically, we investigated the ability of poloxamer 188 (F68) and poloxamer 407 (F127), the two most frequently used PEG-based pharmaceutical excipients, to elicit the production of anti-PEG antibodies and influence the pharmacokinetics of PEGylated nanoparticles, with PEGylated liposome nanoparticles (L-NPs) as a model. Anti-PEG IgG and IgM levels were significantly boosted 3.8- and 32.2-fold, respectively, after pre-injection with F68, leading to rapid clearance of subsequently injected L-NPs from circulation due to the capture by neutrophils and monocytes. However, pre-injection of F127 did not induce the production of anti-PEG IgG, although there was a 7.7-fold increase in IgM level, which resulted in minimal effect on circulation time of L-NPs. Furthermore, the potential clinical impacts of F68 and F127 were further inspected for PEGylated liposomal doxorubicin (PLD). It was found that administering F68 prior to treatment led to over a one-third decrease in the antitumor effectiveness of PLD, while F127 had a negligible impact. Our study elucidates the mechanism by which PEG-based pharmaceutical excipients influence the effectiveness of PEGylated nanomedicines. It also highlights the significance of considering the potential for an ABC effect induced by PEG-based pharmaceutical excipients in patients.

Synthesis of Silver Oxide Nanoparticles: A Novel Approach for Antimicrobial Properties and Biomedical Performance, Featuring Nodularia haraviana from the Cholistan Desert

Nanoparticles have emerged as a prominent area of research in recent times, and silver nanoparticles (AgNPs) synthesized via phyco-technology have gained significant attention due to their potential therapeutic applications. Nodularia haraviana, a unique and lesser-explored cyanobacterial strain, holds substantial promise as a novel candidate for synthesizing nanoparticles. This noticeable research gap underscores the novelty and untapped potential of Nodularia haraviana in applied nanotechnology. A range of analytical techniques, including UV-vis spectral analysis, dynamic light scattering spectroscopy, scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray powder diffraction, were used to investigate and characterize the AgNPs. Successful synthesis of AgNPs was confirmed through UV-visible spectroscopy, which showed a surface plasmon resonance peak at 428 nm. The crystalline size of AgNPs was 24.1 nm. Dynamic light scattering analysis revealed that silver oxide nanoparticles had 179.3 nm diameters and a negative surface charge of -18 mV. Comprehensive in vitro pharmacogenetic properties revealed that AgNPs have significant therapeutic potential. The antimicrobial properties of AgNPs were evaluated by determining the minimum inhibitory concentration against various microbial strains. Dose-dependent cytotoxicity assays were performed on Leishmanial promastigotes (IC50: 18.71 μgmL-1), amastigotes (IC50: 38.6 μgmL-1), and brine shrimps (IC50: 134.1 μg mL-1) using various concentrations of AgNPs. The findings of this study revealed that AgNPs had significant antioxidant results (DPPH: 57.5%, TRP: 55.4%, TAC: 61%) and enzyme inhibition potential against protein kinase (ZOI: 17.11 mm) and alpha-amylase (25.3%). Furthermore, biocompatibility tests were performed against macrophages (IC50: >395 μg mL-1) and human RBCs (IC50: 2124 μg mL-1). This study showed that phyco-synthesized AgNPs were less toxic and could be used in multiple biological applications, including drug design and in the pharmaceutical and biomedical industries. This study offers valuable insights and paves the way for further advancements in AgNPs research.

High-Throughput CAMP Assay (HiTCA): A Novel Tool for Evaluating the Vitamin D-Dependent Antimicrobial Response

Vitamin D is known to modulate human immune responses, and vitamin D deficiency is associated with increased susceptibility to infection. However, what constitutes sufficient levels or whether vitamin D is useful as an adjuvant therapeutic is debated, much in part because of inadequate elucidation of mechanisms underlying vitamin D's immune modulatory function. Cathelicidin antimicrobial peptide (CAMP) has potent broad-spectrum activity, and the CAMP gene is regulated in human innate immune cells by active 1,25(OH)2D3, a product of hydroxylation of inactive 25(OH)D3 by CYP27B1-hydroxylase. We developed a CRISPR/Cas9-edited human monocyte-macrophage cell line containing the mCherry fluorescent reporter gene at the 3' end of the endogenous CAMP gene. The High Throughput CAMP Assay (HiTCA) developed here is a novel tool for evaluating CAMP expression in a stable cell line that is scalable for a high-throughput workflow. Application of HiTCA to serum samples from a small number of human donors (n = 10) showed individual differences in CAMP induction that were not fully accounted for by the serum vitamin D metabolite status of the host. As such, HiTCA may be a useful tool that can advance our understanding of the human vitamin D-dependent antimicrobial response, which is being increasingly appreciated for its complexity.

Green Synthesis of Zinc Oxide Nanoparticles Using Nostoc sp. and Their Multiple Biomedical Properties

Zinc oxide nanoparticles (ZnONPs) are the top candidate in the field of biological applications because of their high surface area and excellent catalytic activities. In the present study, the cyanobacteria-mediated biosynthesis of zinc oxide NPs using Nostoc sp. extract as a stabilizing, chelating, and reducing agent is reported. ZnONPs were biologically synthesized using an eco-friendly and simple technique with a minimal reaction time and calcination temperature. Various methods, including X-ray diffraction (XRD), ultraviolet spectroscopy (UV), Fourier transform infrared (FTIR), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX) were used to characterize the biosynthesized zinc oxide NPs. XRD analysis depicted the crystalline form of zinc oxide NPs, and the Scherrer equation determined a mean crystalline size of ~28.21 nm. The SEM results reveal the spherical shape of the biosynthesized nanoparticles. Various functional groups were involved in the capping and stabilization of the zinc oxide NPs, which were confirmed by FTIR analysis. The zinc oxide NPs showed strong UV-vis absorption at 340 nm. Multiple in vitro biological applications showed significant therapeutic potential for zinc oxide NPs. Potential antimicrobial assays were reported for zinc oxide NPs via the disc-diffusion method and food poisoning method, respectively. All other activities mentioned below are described with the concentration and IC50 values. Biocompatibility with human erythrocytes and macrophages (IC50: 433 µg/mL, IC50 > 323 µg/mL) and cytotoxic properties using brine shrimps (IC50: 11.15 µg/mL) and Leishmania tropics (Amastigotes IC50: 43.14 µg mL−1 and Promastigotes IC50: 14.02 µg mL−1) were determined. Enzyme inhibition assays (protein kinase and alpha amylase) were performed and showed strong potential. Free radical scavenging tests showed strong antioxidant capacities. These results indicate that zinc oxide NPs synthesized by Nostoc sp. have strong biological applications and are promising candidates for clinical development.

Transmigration of macrophages through primary adult rat Sertoli cells

The blood testis barrier (BTB) is often studied with isolated immature Sertoli cells (SCs), transepithelial resistance (TER) measurements and FITC dextran diffusion assays. Recently, it was found that even in the absence of SCs, only few immune cells enter the seminiferous tubules. Thus, in this study, we evaluated the testicular immunological barrier (TIB) in vitro by transmigration of macrophages through SCs with and without peritubular cells (PCs) and with or without matrigel (MG). Primary PCs were isolated from adult rat testis and kept in mono- or co-cultures with the conditionally reprogrammed primary adult Sertoli cell line (PASC1) from rat that has been recently generated by our group. Rat monocytes isolated from fresh blood were differentiated into M0 macrophages, and after polarization to M1 or M2 macrophages characterized by gene expression of CXCL11 and TNF-α for M1, or CCL17 and CCL22 for M2. Transmigration of LeukoTracker-labeled M0, M1, and M2 macrophages through mono- and co-cultures of PCs/SCs with and without MG demonstrated that SCs are the main constituent of the TIB in vitro with only a negligible contribution of PCs or MG. Moreover, M2 macrophages showed less migration activity compared to M0 or M1. Treatment of SCs with testosterone (T) showed positive effects on the barrier in contrast to negative effects by interleukin-6 (IL-6) or tumor necrosis factor-α (TNF-α). The new transmigration model is suitable to evaluate transmigration of macrophages through a barrier consisting of testicular cells and can be applied to study the integrity of testicular barriers with respect to immunological aspects.

Trained immunity - basic concepts and contributions to immunopathology

Trained immunity is a functional state of the innate immune response and is characterized by long-term epigenetic reprogramming of innate immune cells. This concept originated in the field of infectious diseases - training of innate immune cells, such as monocytes, macrophages and/or natural killer cells, by infection or vaccination enhances immune responses against microbial pathogens after restimulation. Although initially reported in circulating monocytes and tissue macrophages (termed peripheral trained immunity), subsequent findings indicate that immune progenitor cells in the bone marrow can also be trained (that is, central trained immunity), which explains the long-term innate immunity-mediated protective effects of vaccination against heterologous infections. Although trained immunity is beneficial against infections, its inappropriate induction by endogenous stimuli can also lead to aberrant inflammation. For example, in systemic lupus erythematosus and systemic sclerosis, trained immunity might contribute to inflammatory activity, which promotes disease progression. In organ transplantation, trained immunity has been associated with acute rejection and suppression of trained immunity prolonged allograft survival. This novel concept provides a better understanding of the involvement of the innate immune response in different pathological conditions, and provides a new framework for the development of therapies and treatment strategies that target epigenetic and metabolic pathways of the innate immune system.

The pyrin inflammasome aggravates inflammatory cell migration in patients with familial Mediterranean fever

BACKGROUND

Familial Mediterranean fever (FMF) is an autoinflammatory disease caused by pathogenic variants of the MEFV gene, which encodes pyrin. Leukocyte migration to serosal sites is a key event during inflammation in FMF. The pyrin inflammasome is a multiprotein complex involved in inflammation. Here, we aimed to determine the relationship between inflammatory cell migration and the pyrin inflammasome in FMF patients.

METHODS

Monocytes were isolated from blood samples collected from patients with FMF, healthy controls, and a patient with cryopyrin-associated periodic syndrome (CAPS), which served as a disease control. Inflammasome proteins were analyzed under inflammasome activation and inhibition by western blotting. Cell migration assays were performed with the isolated primary monocytes as well as THP-1 monocytes and THP-1-derived macrophages.

RESULTS

When the pyrin inflammasome was suppressed, migration of monocytes from FMF patients was significantly decreased compared to the migration of monocytes from the CAPS patient and healthy controls. Cell line experiments showed a relationship between pyrin inflammasome activation and cell migration.

CONCLUSIONS

These findings suggest that the increased cell migration in FMF is due to the presence of more active pyrin inflammasome. This study contributes to our understanding of the role of pyrin in inflammatory cell migration through inflammasome formation.

IMPACT

The pyrin inflammasome may play a role in inflammatory cell migration. FMF patients show a pyrin inflammasome-dependent increase in inflammatory cell migration. Correlations between the pyrin inflammasome and cell migration were observed in both THP-1 monocytes and THP-1-derived macrophages.

Effect of human peripheral blood mononuclear cells (hPBMCs) on mouse endometrial cell proliferation: a potential therapeutics for endometrial regeneration

OBJECTIVES

The persistently thin endometrium is a major cause of repeated implantation failure; however, there is no definite treatment for it yet. This study aimed to confirm the potential of human peripheral blood mononuclear cells (hPBMCs) as a therapeutic agent for endometrial regeneration.

DESIGN

Experimental study Participants/Materials, Setting, Methods: To assess the in vitro effect of hPBMC, the human primary endometrial epithelial cell lines SNU-685 and SNU-1077 were co cultured with or without 1×10^5 hPBMCs for 24 hours. To evaluate the in vivo effect, either 1×10^5 hPBMCs in PBS or PBS alone were injected into the left uterine horn of NOD-SCID mice, and the right untreated uterine horn was used as control.

RESULTS

Co-culture with hPBMCs stimulated significant proliferation in both SNU-685 and SNU-1077 cell lines (p=0.002 and 0.044, respectively). Moreover, treatment with hPBMCs significantly increased the thickness in all parts of the endometrium compared with that in the untreated control uterine horn (proximal: 1.69±0.19 vs. 1.00±0.10, p=0.009; middle: 1.51±0.14 vs. 1.00±0.12, p=0.010; distal: 1.72±0.22 vs. 1.00±0.12, p=0.003, respectively). Compared with the PBS injection group, the hPBMC injection group had significantly thickened endometrium in the middle (P=0.036) and distal segments (P=0.002) of the uterine horn. Immunohistochemical analysis revealed the presence of exogenously injected hPBMCs in the uterus of recipient mice. hPBMC-recipient mice had cyclic uterus with normal histology in the endometrium.

LIMITATIONS

hPBMCs were not applied directly to a mouse model with thin endometrium, so further study is needed.

CONCLUSION

The beneficial effect of hPBMCs on endometrium may suggest their clinical feasibility for the safe treatment of infertile patients with persistently thin endometrium.

Macrophage MerTK promotes profibrogenic cross-talk with hepatic stellate cells via soluble mediators

Background & Aims

Activation of Kupffer cells and recruitment of monocytes are key events in fibrogenesis. These cells release soluble mediators which induce the activation of hepatic stellate cells (HSCs), the main fibrogenic cell type within the liver. Mer tyrosine kinase (MerTK) signaling regulates multiple processes in macrophages and has been implicated in the pathogenesis of non-alcoholic steatohepatitis-related fibrosis. In this study, we explored if MerTK activation in macrophages influences the profibrogenic phenotype of HSCs.

Methods

Macrophages were derived from THP-1 cells or differentiated from peripheral blood monocytes towards MerTK⁺/CD206⁺/CD163⁺/CD209^- macrophages. The role of MerTK was assessed by pharmacologic and genetic inhibition. HSC migration was determined in Boyden chambers, viability was measured by the MTT assay, and proliferation was evaluated by the BrdU incorporation assay.

Results

Gas-6 induced MerTK phosphorylation and Akt activation in macrophages, and these effects were inhibited by UNC569. During polarization, MerTK⁺/CD206⁺/CD163⁺/CD209^- macrophages exhibited activation of STAT3, ERK1/2, p38 and increased expression of VEGF-A. Activation of MerTK in THP-1 macrophages induced a secretome which promoted a significant increase in migration, proliferation, viability and expression of profibrogenic factors in HSCs. Similarly, conditioned medium from MerTK⁺ macrophages induced a significant increase in cell migration, proliferation, STAT3 and p38 phosphorylation and upregulation of IL-8 expression in HSCs. Moreover, conditioned medium from Gas-6-stimulated Kupffer cells induced a significant increase in HSC proliferation. These effects were specifically related to MerTK expression and activity in macrophages, as indicated by pharmacologic inhibition and knockdown experiments.

Conclusions

MerTK activation in macrophages modifies the secretome to promote profibrogenic features in HSCs, implicating this receptor in the pathogenesis of hepatic fibrosis.

Lay summary

Fibrosis represents the process of scarring occurring in patients with chronic liver diseases. This process depends on production of scar tissue components by a specific cell type, named hepatic stellate cells, and is regulated by interaction with other cells. Herein, we show that activation of MerTK, a receptor present in a population of macrophages, causes the production of factors that act on hepatic stellate cells, increasing their ability to produce scar tissue.

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MerTK, a member of the TAM family of proteins, is highly expressed in MerTK⁺/CD206⁺/CD163⁺/CD209^- macrophages.

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In these macrophages, activation of MerTK induces phosphorylation of Akt, STAT3, ERK1/2, p38 and increased expression of VEGF-A.

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MerTK activation in macrophages modulates the secretome to promote the profibrogenic phenotype of human HSCs.

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Profibrogenic effects of macrophages expressing high levels of MerTK were blocked by knockdown or inhibition of MerTK.

Optimized simple and affordable procedure for differentiation of monocyte-derived dendritic cells from LRF: An accessible and valid alternative biological source

Dendritic cells are one of the most popular immune cells, which plays a remarkable role in both immunotherapy and tolerance induction. Due to unwanted side effects of leukocyte presence in donated blood, the policy of blood service is the pre-storage reduction of leukocytes, which today, filtration is the most common method for this purpose. The filtration method has led to diminished access to Buffy coat as a generally used conventional source of biological cells. We developed a simple, affordable, and reproducible method for dendritic cell differentiation from filter-derived monocytes and, the results of the filter study were compared with differentiated DCs from the conventional buffy coat-derived monocytes. The Monocytes were recovered from leukoreduction filter using an optimized protocol with supplemented PBS buffer. Following the adhesion method, CD14⁺ Monocyte-enriched population with the purity of 94 % was obtained. After cytokine stimulation over a 6-day period and maturation induction by LPS, differentiated DCs were evaluated for morphology, surface markers (CD86, CD40, CD83 and, HLA-DR), antigen uptake potency and IL-12 secretion. Analysis and comparison of the results represented no significant difference between the two groups. Accordingly, we conclude that leukoreduction filters could be introduced as a reliable and research-grade source of monocyte for DC generation in biological research.

Molybdenum derived from nanomaterials incorporates into molybdenum enzymes and affects their activities in vivo

Many nanoscale biomaterials fail to reach the clinical trial stage due to a poor understanding of the fundamental principles of their in vivo behaviour. Here we describe the transport, transformation and bioavailability of MoS2 nanomaterials through a combination of in vivo experiments and molecular dynamics simulations. We show that after intravenous injection molybdenum is significantly enriched in liver sinusoid and splenic red pulp. This biodistribution is mediated by protein coronas that spontaneously form in the blood, principally with apolipoprotein E. The biotransformation of MoS2 leads to incorporation of molybdenum into molybdenum enzymes, which increases their specific activities in the liver, affecting its metabolism. Our findings reveal that nanomaterials undergo a protein corona-bridged transport-transformation-bioavailability chain in vivo, and suggest that nanomaterials consisting of essential trace elements may be converted into active biological molecules that organisms can exploit. Our results also indicate that the long-term biotransformation of nanomaterials may have an impact on liver metabolism.

BG-flow, a new flow cytometry tool for G-quadruplex quantification in fixed cells

BACKGROUND

Nucleic acids can fold into non-canonical secondary structures named G-quadruplexes (G4s), which consist of guanine-rich sequences stacked into guanine tetrads stabilized by Hoogsteen hydrogen bonding, π-π interactions, and monovalent cations. G4 structure formation and properties are well established in vitro, but potential in vivo functions remain controversial. G4s are evolutionarily enriched at distinct, functional genomic loci, and both genetic and molecular findings indicate that G4s are involved in multiple aspects of cellular homeostasis. In order to gain a deeper understanding of the function of G4 structures and the trigger signals for their formation, robust biochemical methods are needed to detect and quantify G4 structures in living cells. Currently available methods mostly rely on fluorescence microscopy or deep sequencing of immunoprecipitated DNA or RNA using G4-specific antibodies. These methods provide a clear picture of the cellular or genomic localization of G4 structures but are very time-consuming. Here, we assembled a novel protocol that uses the G4-specific antibody BG4 to quantify G4 structures by flow cytometry (BG-flow).

RESULTS

We describe and validate a flow cytometry-based protocol for quantifying G4 levels by using the G4-specific antibody BG4 to label standard cultured cells (Hela and THP-1) as well as primary cells obtained from human blood (peripheral blood mononuclear cells (PBMCs)). We additionally determined changes in G4 levels during the cell cycle in immortalized MCF-7 cells, and validated changes previously observed in G4 levels by treating mouse macrophages with the G4-stabilizing agent pyridostatin (PDS).

CONCLUSION

We provide mechanistic proof that BG-flow is working in different kinds of cells ranging from mouse to humans. We propose that BG-flow can be combined with additional antibodies for cell surface markers to determine G4 structures in subpopulations of cells, which will be beneficial to address the relevance and consequences of G4 structures in mixed cell populations. This will support ongoing research that discusses G4 structures as a novel diagnostic tool.

Laser Responsive Cisplatin-Gold Nano-Assembly Synergizes the Effect of Cisplatin With Compliance

Cisplatin therapy faces low bioavailability and clastogenic potential limitations. Early payload leakage of nanocarriers may impair adequate therapeutic efficacy. We propose encapsulation of cisplatin in such nanocarrier that can be externally stimulated for high payload release and enhanced toxicity at site of action. Cisplatin conjugated gold nanorods (Pt-AuNRs) have been synthesized and characterized through UV visible spectroscopy, dynamic light scattering and transmission electron microscopy. Physico-chemical characterization through X-ray photon spectrometry confirms the covalent linkage between linker and aquated cisplatin with AuNRs. Laser exposure (850 nm, CW) enabled ~15-fold payload release from Pt-AuNRs nano-assembly, which is quite high (P < 0.0001) compared to non-stimulated conditions. The median growth inhibitory concentration (GI₅₀) after laser exposure of Pt-AuNRs was ~11- and 13-fold low compared to corresponding Pt-AuNRs without laser exposure and cisplatin respectively, in sarcoma cells. Synergistic therapeutic difference is more significant (P < 0.01), at lower concentrations of Pt-AuNRs (0.5-10 μg/mL). Pt-AuNRs photothermal therapy indicates a convincible association of over-production of reactive oxygen species (P < 0.0001) and synergistic therapeutic efficacy. Clastogenic potential is found non-significant for Pt-AuNRs (10 μg/mL). Cisplatin nanoconjugate shows biocompatibility against blood cells. In conclusion, laser-stimulated Pt-AuNRs appear a promising drug delivery with synergistic toxic potential against cancer while attenuating cisplatin toxicity.

Recent Advances in Good Manufacturing Practice-Grade Generation of Dendritic Cells

Dendritic cells (DCs) are pivotal regulators of immune responses, specialized in antigen presentation and bridging the gap between the innate and adaptive immune system. Due to these key features, DCs have become a pillar of the continuously growing field of cellular therapies. Here we review recent advances in good manufacturing practice strategies and their individual specificities in relation to DC production for clinical applications. These take into account both small-scale experimental approaches as well as automated systems for patient care.

Isolation, characterisation and phagocytic function of human macrophages from human peripheral blood

Macrophages are among the most important cells of the immune system. Among other functions, they take part in almost all defense actions against foreign bodies and bacteria, being particularly important in infections, wound healing, and foreign body reactions. Considering their importance for the health of the human body, as well as their important role in several diseases, the in vitro studies based on these cells, are a crucial research field. Taking all mentioned into account, this study describes a simple isolation method of human macrophages (MFUM-HMP-001 and MFUM-HMP-002 cell lines) from peripheral blood. For this purpose, the morphology, the viability, and the phagocytotic activity of the isolated cells were tested. The Immunostaining of MFUM-HMP-001 and MFUM-HMP-002 cells confirmed the macrophage cell markers CD68, CD80, and CD163/M130. The phagocytotic activity was marked in both MFUM-HMP-001 and MFUM-HMP-002 cells, as was the phagocytosis of the pHrodo green Escherichia coli bioparticles conjugates, which was enhanced with the addition of lipopolysaccharide. The cells were stable and exhibited good growth. According to our results, both cell lines are useful for the development of novel macrophage cell-based in vitro models.

Interleukin-35 sensitizes monocytes from patients with asthma to glucocorticoid therapy by regulating p38 MAPK

The activation of monocytes and macrophages is associated with steroid-resistant (SR) asthma. Interleukin-35 (IL-35) is an important anti-inflammatory cytokine, but its regulatory effects on monocytes in patients with SR asthma is not fully understood. Based on clinical response to oral prednisolone, 34 patients with steroid-sensitive (SS) asthma and 20 patients with SR asthma were enrolled in the present study. Serum IL-35 levels were analyzed using the Luminex 200 platform. Monocytes from patients with asthma were pretreated with IL-35 followed by dexamethasone (DEX) and lipopolysaccharide (LPS), then corticosteroid sensitivity was evaluated according to the half-maximal inhibitory concentration of DEX with respect to LPS-induced IL-6 maximal production in monocytes (DEX-IC₅₀). The percentage of maximal inhibition of IL-6 by DEX was presented as E_max. Phosphorylated-P38 mitogen activated kinase (p-p38 MAPK) and mitogen-activated protein kinase phosphatase-1 (MKP-1) were examined by flow cytometry and reverse transcription-quantitative PCR analysis, respectively. Glucocorticoid receptor (GR) binding to the glucocorticoid response element (GRE) was assessed by chromatin immunoprecipitation. Compared with patients with SS asthma, patients with SR asthma had lower IL-35 expression levels (P<0.05). Correlation analysis results demonstrated that the expression levels of IL-35 showed a weak negative correlation with log DEX-IC₅₀ (r=-0.351; P<0.01) and a moderate positive correlation with E_max value (r=0.4501; P<0.01) in all patients with asthma. Moreover, IL-35 enhanced DEX-suppressed IL-6 production and the DEX-induced upregulation of the MKP-1 mRNA expression level in monocytes from both patient groups (P<0.01). In addition, IL-35 inhibited p-p38 MAPK expression in monocytes, and these effects were mediated via an increase in DEX-induced GR binding to GRE. Therefore, IL-35 may be involved in the corticosteroid enhancing effects in monocytes of patients with SR and SS asthma, suggesting potential benefits of IL-35 supplementation in asthmatics with DEX.

Bioactivities of Geranium wallichianum Leaf Extracts Conjugated with Zinc Oxide Nanoparticles

This study attempts to obtain and test the bioactivities of leaf extracts from a medicinal plant, Geranium wallichianum (GW), when conjugated with zinc oxide nanoparticles (ZnONPs). The integrity of leaf extract-conjugated ZnONPs (GW-ZnONPs) was confirmed using various techniques, including Ultraviolet-visible spectroscopy, X-Ray Diffraction, Fourier Transform Infrared Spectroscopy, energy-dispersive spectra (EDS), scanning electron microscopy, transmission electron microscopy, and Raman spectroscopy. The size of ZnONPs was approximately 18 nm, which was determined by TEM analysis. Additionally, the energy-dispersive spectra (EDS) revealed that NPs have zinc in its pure form. Bioactivities of GW-ZnONPs including antimicrobial potentials, cytotoxicity, antioxidative capacities, inhibition potentials against α-amylase, and protein kinases, as well as biocompatibility were intensively tested and confirmed. Altogether, the results revealed that GW-ZnONPs are non-toxic, biocompatible, and have considerable potential in biological applications.

Isolation of Human Peripheral Blood T-Lymphocytes

Peripheral blood is the most common source of T-lymphocytes for in vitro culture. Here, we present a simple and standardized method for small- or large-scale isolation of viable T-lymphocytes and other mononuclear cells from fresh peripheral blood or buffy coat blood samples using the density gradient centrifugation. T-cells obtained using the protocol described here can be used for a variety of downstream analysis, including cellular, molecular, and functional assays.

Extracellular vesicles from early stage Plasmodium falciparum-infected red blood cells contain PfEMP1 and induce transcriptional changes in human monocytes

Pathogens can release extracellular vesicles (EVs) for cell-cell communication and host modulation. EVs from Plasmodium falciparum, the deadliest malaria parasite species, can transfer drug resistance genes between parasites. EVs from late-stage parasite-infected RBC (iRBC-EVs) are immunostimulatory and affect endothelial cell permeability, but little is known about EVs from early stage iRBC. We detected the parasite virulence factor PfEMP1, which is responsible for iRBC adherence and a major contributor to disease severity, in EVs, only up to 12-hr post-RBC invasion. Furthermore, using PfEMP1 transport knockout parasites, we determined that EVs originated from inside the iRBC rather than the iRBC surface. Proteomic analysis detected 101 parasite and 178 human proteins in iRBC-EVs. Primary human monocytes stimulated with iRBC-EVs released low levels of inflammatory cytokines and showed transcriptomic changes. Stimulation with iRBC-EVs from PfEMP1 knockout parasites induced more gene expression changes and affected pathways involved in defence response, stress response, and response to cytokines, suggesting a novel function of PfEMP1 when present in EVs. We show for the first time the presence of PfEMP1 in early stage P. falciparum iRBC-EVs and the effects of these EVs on primary human monocytes, uncovering a new mechanism of potential parasite pathogenesis and host interaction.

Conditional Knockdown of Gene Expression in Cancer Cell Lines to Study the Recruitment of Monocytes/Macrophages to the Tumor Microenvironment

siRNA and shRNA-mediated knock down (KD) methods of regulating gene expression are invaluable tools for understanding gene and protein function. However, in the case that the KD of the protein of interest has a lethal effect on cells or the anticipated effect of the KD is time-dependent, unconditional KD methods are not appropriate. Conditional systems are more suitable in these cases and have been the subject of much interest. These include Ecdysone-inducible overexpression systems, Cytochrome P-450 induction system¹, and the tetracycline regulated gene expression systems. The tetracycline regulated gene expression system enables reversible control over protein expression by induction of shRNA expression in the presence of tetracycline. In this protocol, we present an experimental design using functional Tet-ON system in human cancer cell lines for conditional regulation of gene expression. We then demonstrate the use of this system in the study of tumor cell-monocyte interaction.

Cell to rodent: toxicological profiling of folate grafted thiomer enveloped nanoliposomes

Polymeric nanomaterials, hybridized with lipid components, e.g. phosphocholine or fatty acids, are currently being explored for efficient nano-platforms for hydrophobic drugs. However, their toxicology and toxicokinetics need to be established before enabling their clinical potential. The aim of this study was to investigate the toxicological profile of thiomer enveloped hybrid nanoliposomes (ENLs) and bare nanoliposomes (NLs), loaded with docetaxel (DTX) hydrophobic drug, biocompatible nano-carriers for therapeutic cargo. The in vitro toxicity of hybrid ENLs and NLs was evaluated towards the HCT-116 colon cancer cell line. Biocompatibility was explored against macrophages and acute oral toxicity was examined in mice for 14 days. The anticancer IC50 for ENLs was 0.148 μg ml-1 compared with 2.38 μg ml-1 for pure docetaxel (DTX). The human macrophage viability remained above 65% and demonstrated a high level of biocompatibility and safety of ENLs. In vivo acute oral toxicity showed slight changes in serum biochemistry and haematology but no significant toxicities were observed referring to the safety of DTX loaded hybrid ENLs. On histological examination, no lesions were determined on the liver, heart and kidney. These studies showed that hybrid ENLs can serve as a safe and biocompatible platform for oral delivery of hydrophobic drugs.

Sageretia thea (Osbeck.) mediated synthesis of zinc oxide nanoparticles and its biological applications

Aim: To investigate the physical and biological properties of bioinspired zinc oxide (ZnO) nanoparticles via aqueous leaf extracts of Sageretia thea. Experimental: Nanoparticles of size approximately 12.4 nm were extensively characterized. In vitro antimicrobial, cytotoxic, biocompatible and enzyme inhibition assays were performed. Results: Significant antimicrobial activities with and without UV illumination are reported. Bioinspired ZnO nanoparticles were found effective against fungal strains. MTT assay was performed to check the leishmanicidal activity against promastigotes (IC50: 6.2 μg/ml) and amastigotes (IC50: 10.87 μg/ml) of Leishmania tropica. Brine shrimp lethality was also indicated by bioinspired ZnO nanoparticles (IC50: 21.29 μg/ml). Conclusion: Hemocompatible nature of bioinspired nanoparticles was revealed. Furthermore, the antioxidant activities were performed. In addition, significant protein kinase while insignificant alpha amylase inhibition were recorded.

An investigation of virulence factors of Legionella pneumophila environmental isolates

Nine Legionella pneumophila strains isolated from cooling towers and a standard strain (L. pneumophila serogroup 1, ATCC 33152, Philadelphia 1) were analyzed and compared in terms of motility, flagella structure, ability to form biofilms, enzymatic activities (hemolysin, nucleases, protease, phospholipase A, phospholipase C, acid phosphatase, alkaline phosphatase and lipase), hemagglutination capabilities, and pathogenicity in various host cells (Acanthamoeba castellanii ATCC 30234, mouse peritoneal macrophages and human peripheral monocytes). All the isolates of bacteria appeared to be motile and polar-flagellated and possessed the type-IV fimbria. Upon the evaluation of virulence factors, isolate 4 was found to be the most pathogenic strain, while 6 out of the 9 isolates (the isolates 1, 2, 3, 4, 5, and 7) were more virulent than the ATCC 33152 strain. The different bacterial strains exhibited differences in properties such as adhesion, penetration and reproduction in the hosts, and preferred host type. To our knowledge, this is the first study to compare the virulence of environmental L. pneumophila strains isolated in Turkey, and it provides important information relevant for understanding the epidemiology of L. pneumophila.

Analysis of Mitochondrial Transfer in Direct Co-cultures of Human Monocyte-derived Macrophages (MDM) and Mesenchymal Stem Cells (MSC)

Mesenchymal stem/stromal cells (MSC) are adult stem cells which have been shown to improve survival, enhance bacterial clearance and alleviate inflammation in pre-clinical models of acute respiratory distress syndrome (ARDS) and sepsis. These diseases are characterised by uncontrolled inflammation often underpinned by bacterial infection. The mechanisms of MSC immunomodulatory effects are not fully understood yet. We sought to investigate MSC cell contact-dependent communication with alveolar macrophages (AM), professional phagocytes which play an important role in the lung inflammatory responses and anti-bacterial defence. With the use of a basic direct co-culture system, confocal microscopy and flow cytometry we visualised and effectively quantified MSC mitochondrial transfer to AM through tunnelling nanotubes (TNT). To model the human AM, primary monocytes were isolated from human donor blood and differentiated into macrophages (monocyte derived macrophages, MDM) in the presence of granulocyte macrophage colony-stimulating factor (GM-CSF), thus allowing adaptation of an AM-like phenotype (de Almeida et al., 2000; Guilliams et al., 2013). Human bone-marrow derived MSC, were labelled with mitochondria-specific fluorescent stain, washed extensively, seeded into the tissue culture plate with MDMs at the ratio of 1:20 (MSC/MDM) and co-cultured for 24 h. TNT formation and mitochondrial transfer were visualised by confocal microscopy and semi-quantified by flow cytometry. By using the method we described here we established that MSC use TNTs as the means to transfer mitochondria to macrophages. Further studies demonstrated that mitochondrial transfer enhances macrophage oxidative phosphorylation and phagocytosis. When TNT formation was blocked by cytochalasin B, MSC effect on macrophage phagocytosis was completely abrogated. This is the first study to demonstrate TNT-mediated mitochondrial transfer from MSC to innate immune cells.

Preparation of CD4+ T Cells for Analysis of GD3 and GD2 Ganglioside Membrane Expression by Microscopy

The methods described herein for activation of naïve CD4⁺ T cells in suspension and their adherence in coverslips for confocal microscopy analysis allow the spatial localization and visualization of gangliosides involved in CD4⁺ T cell activation, that complement expression profiling experiments such as flow cytometry, western blotting or real-time PCR. The quantification of ganglioside expression through flow cytometry and their cellular localization through microscopy can be obtained by the use of anti-ganglioside antibodies with high affinity and specificity. Nonetheless, an adequate handling of cells in suspension involves the treatment of culture plates to promote the necessary adherence required for fluorescence or confocal microscopy acquisition. In this work, we describe a protocol for determining GD3 and GD2 ganglioside expression and colocalization with the TCR during naïve CD4⁺ T cell activation. Also, real-time PCR experiments using <40,000 cells are described for the determination of the GD3 and GM2/GD2 synthase genes, demonstrating that gene analysis experiments can be performed with a low number of cells and without the need of additional low input RNA kits.

Comparison of cellular effects of starch-coated SPIONs and poly(lactic-co-glycolic acid) matrix nanoparticles on human monocytes

Within the last years, progress has been made in the knowledge of the properties of medically used nanoparticles and their toxic effects, but still, little is known about their influence on cellular processes of immune cells. The aim of our comparative study was to present the influence of two different nanoparticle types on subcellular processes of primary monocytes and the leukemic monocyte cell line MM6. We used core-shell starch-coated superparamagnetic iron oxide nanoparticles (SPIONs) and matrix poly(lactic-co-glycolic acid) (PLGA) nanoparticles for our experiments. In addition to typical biocompatibility testing like the detection of necrosis or secretion of interleukins (ILs), we investigated the impact of these nanoparticles on the actin cytoskeleton and the two voltage-gated potassium channels Kv1.3 and Kv7.1. Induction of necrosis was not seen for PLGA nanoparticles and SPIONs in primary monocytes and MM6 cells. Likewise, no alteration in secretion of IL-1β and IL-10 was detected under the same experimental conditions. In contrast, IL-6 secretion was exclusively downregulated in primary monocytes after contact with both nanoparticles. Two-electrode voltage clamp experiments revealed that both nanoparticles reduce currents of the aforementioned potassium channels. The two nanoparticles differed significantly in their impact on the actin cytoskeleton, demonstrated via atomic force microscopy elasticity measurement and phalloidin staining. While SPIONs led to the disruption of the respective cytoskeleton, PLGA did not show any influence in both experimental setups. The difference in the effects on ion channels and the actin cytoskeleton suggests that nanoparticles affect these subcellular components via different pathways. Our data indicate that the alteration of the cytoskeleton and the effect on ion channels are new parameters that describe the influence of nanoparticles on cells. The results are highly relevant for medical application and further evaluation of nanomaterial biosafety.

Preparation of purified perikaryal and synaptosomal mitochondrial fractions from relatively small hypothalamic brain samples

In order to measure the activity of neuronal mitochondria, a representative proof of neuronal processes, physiologically relevant mitochondrial samples need to be gained as simply as possible. Existing methods are, however, either for tissue samples of large size and/or homogenous microstructures only, or are not tested for mitochondrial function measurements. In the present article we describe a gradient fractionation method to isolate viable and well-coupled mitochondria from relatively heterogeneous histological microstructures such as the hypothalamus. With this new method, we are able to isolate a sufficient amount of functional mitochondria for determination of respiratory activity, in a short period of time, using affordable equipment. •Verified by electron microscopy, our method separates highly enriched and well-preserved perikaryal and synaptosomal mitochondria. Both fractions contain minimal cell debris and no myelin. Respiratory measurements (carried out by Clark-type electrode) confirmed undisturbed mitochondrial function providing well-evaluable records. The demonstrated protocol yields highly viable mitochondrial subfractions within 3 h from small brain areas for high-precision examinations. Using this procedure, brain regions with relatively heterogeneous histological microstructure (hypothalamus) can also be efficiently sampled.•Up to our present knowledge, our method is the shortest available procedure with the lowest sample size to gain debris-free, fully-viable mitochondria.

Hemin Preconditioning Upregulates Heme Oxygenase-1 in Deceased Donor Renal Transplant Recipients: A Randomized, Controlled, Phase IIB Trial

BACKGROUND

The enzyme heme oxygenase-1 (HO-1) degrades heme and protects against ischemia-reperfusion injury. Monocytes/macrophages are the major source of HO-1 and higher levels improve renal transplant outcomes. Heme arginate (HA) safely induces HO-1 in humans.

METHODS

The Heme Oxygenase-1 in renal Transplantation study was a randomized, placebo-controlled, IIb trial to evaluate HA effect on HO-1 upregulation after deceased donor kidney transplantation. 40 recipients were randomized to either 3 mg kg HA or placebo (0.9% NaCl), given preoperatively (day 0) and again on day 2. Recipient blood and urine were collected daily. Graft biopsies were taken preoperatively and on day 5. Primary outcome was HO-1 upregulation in peripheral blood mononuclear cells (PBMCs). Secondary outcomes were graft HO-1 upregulation and injury, urinary biomarkers, and renal function.

RESULTS

The HA upregulated PBMC HO-1 protein more than placebo at 24 hours: HA 11.1 ng/mL versus placebo 0.14 ng/mL (P = < 0.0001). The PBMC HO-1 messenger RNA also increased: HA 2.73-fold versus placebo 1.41-fold (P = 0.02). Heme arginate increased day 5 tissue HO-1 protein immunopositivity compared with placebo: HA 0.21 versus placebo -0.03 (P = 0.02) and % HO-1-positive renal macrophage also increased: HA 50.8 cells per high power field versus placebo 22.3 (P = 0.012). Urinary biomarkers were reduced after HA but not significantly. Histological injury and renal function were similar but the study was not powered for this. Adverse events were equivalent between groups.

CONCLUSIONS

The primary outcome was achieved and demonstrated for the first time that HA safely induces HO-1 in transplant recipients. Planned larger studies will determine the impact of HO-1 upregulation on clinical outcomes and evaluate the benefit to patients at risk of ischemia-reperfusion injury.

The Effect of Bacteriophage Preparations on Intracellular Killing of Bacteria by Phagocytes

Intracellular killing of bacteria is one of the fundamental mechanisms against invading pathogens. Impaired intracellular killing of bacteria by phagocytes may be the reason of chronic infections and may be caused by antibiotics or substances that can be produced by some bacteria. Therefore, it was of great practical importance to examine whether phage preparations may influence the process of phagocyte intracellular killing of bacteria. It may be important especially in the case of patients qualified for experimental phage therapy (approximately half of the patients with chronic bacterial infections have their immunity impaired). Our analysis included 51 patients with chronic Gram-negative and Gram-positive bacterial infections treated with phage preparations at the Phage Therapy Unit in Wroclaw. The aim of the study was to investigate the effect of experimental phage therapy on intracellular killing of bacteria by patients' peripheral blood monocytes and polymorphonuclear neutrophils. We observed that phage therapy does not reduce patients' phagocytes' ability to kill bacteria, and it does not affect the activity of phagocytes in patients with initially reduced ability to kill bacteria intracellularly. Our results suggest that experimental phage therapy has no significant adverse effects on the bactericidal properties of phagocytes, which confirms the safety of the therapy.

Arsenic Exposure Increases Monocyte Adhesion to the Vascular Endothelium, a Pro-Atherogenic Mechanism

Epidemiological studies have shown that arsenic exposure increases atherosclerosis, but the mechanisms underlying this relationship are unknown. Monocytes, macrophages and platelets play an important role in the initiation of atherosclerosis. Circulating monocytes and macrophages bind to the activated vascular endothelium and migrate into the sub-endothelium, where they become lipid-laden foam cells. This process can be facilitated by platelets, which favour monocyte recruitment to the lesion. Thus, we assessed the effects of low-to-moderate arsenic exposure on monocyte adhesion to endothelial cells, platelet activation and platelet-monocyte interactions. We observed that arsenic induces human monocyte adhesion to endothelial cells in vitro. These findings were confirmed ex vivo using a murine organ culture system at concentrations as low as 10 ppb. We found that both cell types need to be exposed to arsenic to maximize monocyte adhesion to the endothelium. This adhesion process is specific to monocyte/endothelium interactions. Hence, no effect of arsenic on platelet activation or platelet/leukocyte interaction was observed. We found that arsenic increases adhesion of mononuclear cells via increased CD29 binding to VCAM-1, an adhesion molecule found on activated endothelial cells. Similar results were observed in vivo, where arsenic-exposed mice exhibit increased VCAM-1 expression on endothelial cells and increased CD29 on circulating monocytes. Interestingly, expression of adhesion molecules and increased binding can be inhibited by antioxidants in vitro and in vivo. Together, these data suggest that arsenic might enhance atherosclerosis by increasing monocyte adhesion to endothelial cells, a process that is inhibited by antioxidants.

Extracellular signal-regulated kinase 5 promotes acute cellular and systemic inflammation

Inflammatory critical illness is a syndrome that is characterized by acute inflammation and organ injury, and it is triggered by infections and noninfectious tissue injury, both of which activate innate immune receptors and pathways. Although reports suggest an anti-inflammatory role for the mitogen-activated protein kinase (MAPK) extracellular signal-regulated kinase 5 (ERK5), we previously found that ERK5 mediates proinflammatory responses in primary human cells in response to stimulation of Toll-like receptor 2 (TLR2). We inhibited the kinase activities and reduced the abundances of ERK5 and MEK5, a MAPK kinase directly upstream of ERK5, in primary human vascular endothelial cells and monocytes, and found that ERK5 promoted inflammation induced by a broad range of microbial TLR agonists and by the proinflammatory cytokines interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α). Furthermore, we found that inhibitors of MEK5 or ERK5 reduced the plasma concentrations of proinflammatory cytokines in mice challenged with TLR ligands or heat-killed Staphylococcus aureus, as well as in mice that underwent sterile lung ischemia-reperfusion injury. Finally, we found that inhibition of ERK5 protected endotoxemic mice from death. Together, our studies support a proinflammatory role for ERK5 in primary human endothelial cells and monocytes, and suggest that ERK5 is a potential therapeutic target in diverse disorders that cause inflammatory critical illness.

Leishmania infection modulates beta-1 integrin activation and alters the kinetics of monocyte spreading over fibronectin

Contact with Leishmania leads to a decreases in mononuclear phagocyte adherence to connective tissue. In this work, we studied the early stages of bond formation between VLA4 and fibronectin, measured the kinetics of membrane alignment and the monocyte cytoplasm spreading area over a fibronectin-coated surface, and studied the expression of high affinity integrin epitope in uninfected and Leishmania-infected human monocytes. Our results show that the initial VLA4-mediated interaction of Leishmania-infected monocyte with a fibronectin-coated surface is preserved, however, the later stage, leukocyte spreading over the substrate is abrogated in Leishmania-infected cells. The median of spreading area was 72 [55–89] μm² for uninfected and 41 [34–51] μm² for Leishmania-infected monocyte. This cytoplasm spread was inhibited using an anti-VLA4 blocking antibody. After the initial contact with the fibronectrin-coated surface, uninfected monocyte quickly spread the cytoplasm at a 15 μm² s⁻¹ ratio whilst Leishmania-infected monocytes only made small contacts at a 5.5 μm² s⁻¹ ratio. The expression of high affinity epitope by VLA4 (from 39 ± 21% to 14 ± 3%); and LFA1 (from 37 ± 32% to 18 ± 16%) molecules was reduced in Leishmania-infected monocytes. These changes in phagocyte function may be important for parasite dissemination and distribution of lesions in leishmaniasis.

Expression of adenosine receptors in monocytes from patients with bronchial asthma

Adenosine is generated from adenosine triphosphate, which is released by stressed and damaged cells. Adenosine levels are significantly increased in patients with bronchial asthma (BA) and mediate mast cell degranulation and bronchoconstriction. Over the last decade, increasing evidence has shown that adenosine can modulate the innate immune response during monocytes differentiation towards mature myeloid cells. These adenosine-differentiated myeloid cells, characterized by co-expression of monocytes/macrophages and dendritic cell markers such as CD14 and CD209, produce high levels of pro-inflammatory cytokines, thus contributing to the pathogenesis of BA and chronic obstructive pulmonary disease. We found that expression of ADORA2A and ADORA2B are increased in monocytes obtained from patients with BA, and are associated with the generation of CD14(pos)CD209(pos) pro-inflammatory cells. A positive correlation between expression of ADORA2B and IL-6 was identified in human monocytes and may explain the increased expression of IL-6 mRNA in asthmatics. Taken together, our results suggest that monocyte-specific expression of A2 adenosine receptors plays an important role in pro-inflammatory activation of human monocytes, thus contributing to the progression of asthma.

Role of diallyl disulfide-mediated cleavage of c-Myc and Sp-1 in the regulation of telomerase activity in human lymphoma cell line U937

OBJECTIVE

Garlic (Allium sativum) has been considered a wonder herb for years with a reputation of disease prevention. Telomerase, a ribonucleoprotein enzyme responsible for telomere integrity, is strongly up-regulated in different types of cancers. The aim of this study was to reveal the role of diallyl disulfide (DADS), an organosulfur component of garlic, on telomerase activity in human lymphoma with an emphasis on key transcription factors c-Myc and Sp-1.

METHODS

Human lymphoma cell line U937 was used as model cell line. Telomerase activity was measured by telomerase repeat amplification protocol assay, levels of related proteins and mRNAs were measured by Western blot and reverse transcriptase polymerase chain reaction, respectively. Moreover, in vitro binding assay was performed using radiolabeled double-stranded DNA having specific sequences to detect involvement of transcription factors in DADS-dependent modulation of telomerase activity.

RESULTS

The present study demonstrated DADS-mediated decrease in telomerase activity in U937 cells with concomitant transcriptional down-regulation of human telomerase reverse transcriptase (hTERT) that is caused by reduced binding of c-Myc and Sp-1 to their respective binding sites on hTERT promoter. Lowering of DNA-binding activity of c-Myc and Sp-1 due to DADS treatment is caused by the deactivation of these transcription factors due to cleavage. Additionally, Mad1-the repressor protein of hTERT expression-is also overexpressed in DADS-treated U937 cells.

CONCLUSIONS

These findings strongly suggest that DADS down-regulate telomerase activity through c-Myc-, Sp-1-, and Mad1-dependent transcriptional down-regulation of hTERT.

Improving the methods for isolation of monocyte and establishing macrophage cell culture in caprine model

Monocytes are widely used for immunological research, especially in the study of innate immune system. Although methods for isolation of human monocytes have been established, the procedure for non-human monocyte has not been well developed. This paper describes an improved method for isolation of monocyte and the subsequent macrophage cultivation from caprine blood. Monocytes were isolated from 16 ml of heparinized caprine blood using double density methods; the Ficoll and Percoll. The number of monocytes obtained was 5.12 ± 0.89 × 10(7) cells/ml at 70 % purity. The isolated monocytes were maintained in 10 % fetal bovine serum-enriched Dulbecco's Modified Eagle Medium for maturation to form macrophage cell culture. At the end of the experiment, the harvested macrophage was 2.48 ± 0.33 × 10(6) cells/ml.