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KMRC011 is a novel Toll‐like receptor 5 agonist under development as a treatment for acute radiation syndrome (ARS). The aim of this first‐in‐human study was to investigate the tolerability, pharmacokinetics, and pharmacodynamics of a single intramuscular dose of KMRC011 in healthy subjects. A randomized, single‐blind, placebo‐controlled, single dose‐escalation study was conducted with the starting dose of 5 μg. Eight (4 only for 5 μg cohort) subjects per cohort were randomly assigned to KMRC011 or placebo in a 3:1 ratio. Dose‐limiting toxicity (DLT) was assessed throughout the study. Serum concentrations of KMRC011, granulocyte colony‐stimulating factor (G‐CSF), and interleukin‐6 (IL‐6) were measured up to 48 h postdose. Based on safety review, the dose of KMRC011 escalated up to 20 μg, and consequently, a total of 4 dose levels (5, 10, 15, and 20 μg) were explored. The most common adverse event was injection site reaction, showing no dose‐related trend. Three DLTs (2 cases of hepatic enzyme increased and 1 of pyrexia) were observed; 1 in the 15 μg cohort and 2 in the 20 μg cohort. A developed method could not detect any KMRC011 in serum. KMRC011 15 μg and 20 μg showed significant increases of G‐CSF, IL‐6, and absolute neutrophil counts, compared with the placebo. A single intramuscular administration of KMRC011 ranging from 5 to 15 μg was tolerated in healthy subjects. Doses of KMRC011 equal to or greater than 15 μg exerted TLR5 agonist‐like activities by increasing serum G‐CSF and IL‐6. It suggests that KMRC011 has the potential for a treatment for ARS.

BACKGROUND: Human adipose tissue-derived stem cells (ADSCs) are attractive multipotent stem cell sources with therapeutic potential in various fields requiring repair and regeneration, such as acute and chronically damaged tissues. ADSC is suitable for cell-based therapy, but its use has been hampered due to poor survival after administration. Potential therapeutic use of ADSC requires mass production of cells through in vitro expansion. Many studies have consistently observed the tendency of senescence by mesenchymal stem cell (MSC) proliferation upon expansion. Hypoxia has been reported to improve stem cell proliferation and survival. METHODS: We investigated the effects of hypoxia pretreatment on ADCS proliferation, migration capacity, differentiation potential and cytokine production. We also analyzed the effects of vascular endothelial growth factor (VEGF) on osteogenic and chondrogenic differentiation of ADSCs by hypoxia pretreatment. RESULTS: Hypoxia pretreatment increased the proliferation of ADSCs by increasing VEGF levels. Interestingly, hypoxia pretreatment significantly increased chondrogenic differentiation but decreased osteogenic differentiation compared to normoxia. The osteogenic differentiation of ADSC was decreased by the addition of VEGF but increased by the depletion of VEGF. We have shown that hypoxia pretreatment increases the chondrogenic differentiation of ADSCs while reducing osteogenic differentiation in a VEGF-dependent manner. CONCLUSION: These results show that hypoxia pretreatment can provide useful information for studies that require selective inhibition of osteogenic differentiation, such as cartilage regeneration. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s13770-020-00265-5) contains supplementary material, which is available to authorized users.

We have synthesized and characterized photophysical properties of a novel contrast agent based on switchable near-infrared (NIR) fluorescent nanoprobes that enables optical imaging with a higher sensitivity than conventional contrast agents allow. The high sensitivity was a result not only of the intrinsically high signal-to-background ratio that could be obtained in the NIR spectral region, but also from the increased signal intensity that was provided by using activatable nanoprobes. The NIR fluorescent nanoprobes were synthesized by encapsulating indocyanine green (ICG) into pH-responsive polymer nanoparticles. The intensity of the NIR fluorescence signal from the nanoparticles increased about 11-fold in acidic solution, due to the release of ICG molecules from the nanoparticles. The efficacy of fluorescence recovery from the quenched state to the de-quenched state could be modulated by controlling the relative concentrations between pH-responsive polymer and ICG. The fluorescence recovery properties of switchable NIR nanoprobes were also evaluated by cellular uptake experiments. Our experimental results support the use of pH-responsive nanoparticles with incorporated contrast agents as activatable molecular imaging nanoprobes.

Sun-Hee Cho,1,* Ji Hyeon Hong,2,* Young-Woock Noh,1 Eunji Lee,2 Chang-Soo Lee,3 Yong Taik Lim1 1SKKU Advanced Institute of Nanotechnology, School of Chemical Engineering, Sungkyunkwan University, Suwon, Gyeonggi-do, 2Graduate School of Analytical Science and Technology, Chungnam National University, 3Hazards Monitoring Bionano Research Center, Korea Research Institute of Bioscience and Biotechnology, Yuseong-gu, Daejeon, Republic of Korea *These authors contributed equally tothis work Abstract: In this research, we synthesized bioderived poly(amino acid) hydrogel particles that showed pH-dependent membrane-disrupting properties and controlled cytosolic delivery of antitumor drugs. Poly(γ-glutamic acid) (γ-PGA) that has been produced extensively using bacteria, especially those of Bacillus subtilis species, was modified with cholesterol (γ-PGA/Chol), and the γ-PGA/Chol conjugates were used to form polymeric nanoparticles the size of 21.0±1.1nm in aqueous solution. When the polymeric nanoparticles were mixed with doxorubicin (Dox), raspberry-like hydrogel particles (RBHPs) were formed by the electrostatic interaction between the cationically charged Dox and the anionically charged nanoparticles. The average size and surface charge of the RBHPs in aqueous solution were 444.9±122.5nm and -56.44mV, respectively. The loaded amount of Dox was approximately 63.9µg/mg of RBHPs. The RBHPs showed controlled drug release behavior in both in vitro and ex vivo cell-based experiments. Through fluorescence microscopy and fluorescence-activated cell sorting, the cellular uptake of RBHPs into human cervical cancer cells (HeLa) was analyzed. The cytotoxic effect, evaluated by the methyl tetrazolium salt assay, was dependent on both the concentration of RBHPs and the treatment time. The pH-dependent membrane-disrupting properties of the RBHPs and the subsequent cytosolic delivery of Dox were evaluated using a standard hemolysis assay. Upon an increase in hydrophobicity at the lysosomal acidic pH, RBHPs could easily interact, penetrate cell membranes, and destabilize them. Taken together, the data suggested that RBHPs could be used as drug delivery carriers after loading with other therapeutic drugs, such as proteins or small interfering RNA for cancer therapy. Keywords: hydrogel particles, controlled release, endosomal escape, antitumor

Seasonal emerging infectious diseases such as influenza A impose substantial risk and need new translational strategies to achieve active immunomodulation. Here, a novel injectable pathogen-mimicking hydrogel (iPMH) that can enhance both cellular and humoral immune responses is suggested. By the help of poly(γ-glutamic acid) that has abundant carboxylate groups and dispersion helper function, hydrophobic immunostimulatory 3-O-desacyl-4'-monophosphoryl lipid A (MPLA) molecules and viral antigens (PR8, W150) can be successfully combined as pathogen-mimicking adjuvants. Polyelectrolyte complex between the poly(γ-glutamic acid)-based adjuvants and collagens generate in situ gel-forming hydrogel at physiological temperature. When the iPMH are immunized, they act as a pathogen-mimicking (MPLA, H1N1, H5N1) immune priming center and a depot for continuous stimulation of immune system, resulting in the induction of high levels (8.5 times higher) of antigen-specific IgG titers in the sera of mice and the increased number of IFN-γ-producing cells (7.3 times higher) compared with those in the groups immunized with antigen plus clinically used aluminum gels. Following the intranasal infection of the mouse adapted virus (emerging infectious 2009 H1N1 and highly pathogenic 2006 H5N1) at 50 times the 50% lethal dose, the mice immunized with viral antigens plus iPMH exhibit 100% protective immunity against lethal virus challenge.

Double-strand breaks (DSBs) are repaired through two major pathways, homology-directed recombination (HDR) and non-homologous end joining (NHEJ). The choice between these two pathways is largely influenced by cell cycle phases. HDR can occur only in S/G2 when sister chromatid can provide homologous templates, whereas NHEJ can take place in all phases of the cell cycle except mitosis. Central to NHEJ repair is the Ku70/80 heterodimer which forms a ring structure that binds DSB ends and serves as a platform to recruit factors involved in NHEJ. Upon completion of NHEJ repair, DNA double strand-encircling Ku dimers have to be removed. The removal depends on ubiquitylation and proteasomal degradation of Ku80 by the ubiquitin E3 ligases RNF8. Here we report that RNF8 is a substrate of APC(Cdh1) and the latter keeps RNF8 level in check at DSBs to prevent premature turnover of Ku80.

Double-strand breaks (DSBs) are repaired through two major pathways, homology-directed recombination (HDR) and non-homologous end joining (NHEJ). The choice between these two pathways is largely influenced by cell cycle phases. HDR can occur only in S/G2 when sister chromatid can provide homologous templates, whereas NHEJ can take place in all phases of the cell cycle except mitosis. Central to NHEJ repair is the Ku70/80 heterodimer which forms a ring structure that binds DSB ends and serves as a platform to recruit factors involved in NHEJ. Upon completion of NHEJ repair, DNA double strand-encircling Ku dimers have to be removed. The removal depends on ubiquitylation and proteasomal degradation of Ku80 by the ubiquitin E3 ligases RNF8. Here we report that RNF8 is a substrate of APCCdh1 and the latter keeps RNF8 level in check at DSBs to prevent premature turnover of Ku80.

Here, monophosphoryl lipid A (MPLA) and aluminum salt (Alum) were introduced into a hyaluronic acid (HA)-based combination vaccine adjuvant for hepatitis B vaccine (HBV). Although Alum is a well-known hepatitis B vaccine adjuvant that induces an enhanced humoral immune response, it cannot induce the cellular immune responses. On the other hand, MPLA has been generally reported to promote IFN-γ production via antigen-specific CD4(+) T cells, but it is not water soluble as a result of its long hydrophobic alkyl chains. To this end, water insoluble MPLA could be solubilized in an aqueous solution with the help of HA, which contains many carboxyl and hydroxyl groups that can be used to attach to the hydroxyl head groups of MPLA via hydrogen bonds. Three groups of mice were treated with either hepatitis B surface antigen (HBsAg) alone, HBsAg_Alum complex, or HBsAg_Alum_MPLA/HA complex. The group immunized with the HBsAg_Alum_MPLA/HA complex exhibited a high increase in cellular immune response as well as in humoral immune response relative to the other two groups. The antibody, cytokine and T cell levels were most elevated in the group of mice immunized with HBsAg_Alum_MPLA/HA complex, even at a 1μg/mice dose, and the magnitude was still maintained even after 8 weeks. Specifically, the antibody value was 120 times larger in mice vaccinated with HBsAg_Alum_MPLA/HA complex than in mice vaccinated with HBsAg_Alum complex designed similar to commercially available hepatitis B vaccine, Engerix B. The cytokine and T cell proliferation levels were 2 times and 6 times larger in mice adjuvanted with HBsAg_Alum_MPLA/HA complex than in those vaccinated with HBsAg_Alum. The results therefore indicate that incorporating MPLA and Alum with HA can be a potent strategy to increase both the magnitude and the persistence of HBsAg-specific immune responses to protect hosts against hepatitis B virus infection.

This study aimed to examine tracers designed to overcome the disadvantages of indocyanine green (ICG), which disperses quickly to multiple lymph nodes, using a near-infrared (NIR) imaging system in animal models. Diluted ICG, ICG/poly-γ-glutamic acid (PGA) complex, and IRDye900-conjugated pullulan-cholesterol nanoprobe “near-infrared polynagogel” (NIR-PNG) were injected into the stomachs of dogs and pigs, and the patterns of dispersion were observed using an NIR imaging system. To compare retention times, fluorescence signals were evaluated in the stomach and small bowel of animals 1 week after injection. A diluted concentration (~0.1 mg/ml) of ICG was optimal for NIR imaging compared with the conventional concentration (5 mg/ml) for visual inspection. When injected into the stomach, the signals of ICG and ICG/PGA complex were relatively large at the injection site, and signals were detected at multiple sentinel nodes and lymph nodes beyond them. The NIR-PNG signal intensity was relatively small at the injection site and limited to only one sentinel node with no additional node. When evaluated 1 week after injection, only the NIR-PNG signal was detected in the canine stomach, and the signal intensity at the lymph nodes of the porcine small bowel was the highest with NIR-PNG, followed by ICG/PGA complex and finally ICG. NIR-PNG showed the best characteristics of less dispersion and longer retention in the sentinel nodes, and ICG/PGA complex remained longer than diluted ICG. These tracers could potentially be used as optimal tracers for sentinel node navigation surgery in gastric cancer.

Micelles for mucosal immunity: A mucosal vaccine system based on γ-PGA nanomicelles and viral antigens was synthesized. The intranasal administration of the vaccine system induces a high immune response both in the humoral and cellular immunity (see picture).

Purpose We determined whether poly(lactic-co-glycolic acid) nanoparticles would be a useful reagent for the successful monitoring of isolated islets by magnetic resonance imaging and optical imaging systems, without clinically relevant toxicity in vitro or in vivo. Methods We used iron oxide for MR imaging and a cyanide dye approved by the Food and Drug Administration (indocyanine green) for optical imaging and estimated the in vivo detection of transplanted pancreatic islets. Results The poly(lactic-co-glycolic acid) nanoparticles were associated with the islets in vitro and were successfully detected by 4.7 T (MR) and optical imaging, without other toxic effects. When labeled islets were transplanted under the mouse kidney capsule, in vivo T2/ -weighted scans with 4.7 T MR detected as few as 300 labeled islets by 4 weeks. Optical in vivo imaging revealed indocyanine green fluorescence by 2 and 4 days after transplantation of islets containing 250 and 500 µg/mL poly(lactic-co-glycolic acid) nanoparticles, respectively. These results were further supported by the immunohistochemical results for insulin and iron in the recipient mouse kidney and pancreas. Conclusions Taken together, these data indicate that poly(lactic-co-glycolic acid) nanoparticles may be used to label transplanted islets and may be imaged with in vivo MR and optical imaging systems. Magn Reson Med 71:1054–1063, 2014. © 2013 Wiley Periodicals, Inc.

In this study, synthetic vaccine nanoparticles (SVNPs) that efficiently targeted lymph nodes, where immune responses against foreign antigens are primed, were developed to enhance antitumor immunity. The size (20–70 nm) and surface character (amination) of poly(γ-glutamic acid)-based SVNPs were selected for effective loading and delivery ( i.e ., migration and retention) of model tumor antigen (OVA) and toll-like receptor 3 agonist (poly (I:C)) to immune cells in lymph nodes. Antigen-presenting cells treated with SVNP-OVA and SVNP-IC showed higher uptake of OVA and poly (I:C) and higher secretion of inflammatory cytokines (TNF-α, IL-6) and type I interferon (IFN-α, IFN-β) than those treated with OVA and poly (I:C) alone. In vivo analysis revealed higher levels of activation markers, inflammatory cytokines, and type I IFNs in the lymph nodes of mice immunized with SVNP-IC compared to those of mice in other groups. SVNP-IC-treated mice showed significantly greater in vivo natural killer cell expansion/activation (NK1.1 + cells) and CD8 + T cell response (CD8 + INF-γ + cells) in innate and adaptive immunity, respectively. Both preventive and therapeutic vaccination of EG7-OVA tumor-bearing mice using the simultaneous injection of both SVNP-OVA and SVNP-IC induced higher antitumor immunity and inhibited tumor growth.

In this study, we developed electrostatically self-assembled ternary nanocomplexes as a safe and effective non-viral vector for the delivery of plasmid DNA (pDNA) into human adipose-derived stem cells (hASCs). Although polyethylenimine (PEI) polymers initially showed excellent performance as gene delivery carriers, their broad use has been limited by cytotoxicity resulting from their strong positive charge. To reduce the cytotoxicity, we utilized anionic hyaluronic acid (HA) as a corona layer material for pDNA/PEI binary nanocomplexes. HA was also introduced to increase the targeting efficiency of pDNA/PEI nanocomplexes because HA has can bind CD44 that is highly expressed on the surface of hASCs. We confirmed that the addition of HA changed the surface charge of pDNA/PEI nanocomplexes from positive to negative. The pDNA/PEI/HA ternary nanocomplexes showed high transfection efficiency and low cytotoxicity compared with commercially available products. When hASCs were pretreated with HA to passivate CD44, the transfection efficiency of pDNA/PEI/HA nanocomplexes was significantly reduced. These results suggest that HA that can act as a targeting ligand to CD44 contributed to the improved transfection of pDNA into hASCs. Our novel pDNA/PEI/HA nanocomplexes may be used as an effective non-viral pDNA delivery system for hASCs.

A novel powder-form combination adjuvant system containing two immunostimulatory compounds was firstly developed and evaluated as a therapeutic intervention for cancer immunotherapy. With the help of hyaluronic acid (HA), water insoluble monophosphoryl lipid A (MPL), QS21 and imiquimod (R837), could be easily dispersed in aqueous solution and lyophilized as powder-form, which have an advantage in room-temperature storage stability compared with those conventional liquid formulation that requires cold storage. Two kinds of HA-based combination vaccine adjuvants (HA/MPL/QS21, HMQ and HA/MPL/R837, HMR) contributed to the increase of both humoral and cellular immunity, which is very important for efficient cancer immunotherapy. Through the challenge experiments in EG7-OVA (mouse lymphoma-expressing OVA) tumor-bearing mice model, we found out that the immunostimulatory effects of HMQ and HMR were successful in the inhibition of tumor proliferation. Taken together, both HA-based powder-form combination adjuvant systems are expected to be used as potent prophylactic and therapeutic cancer vaccine.

Chanyoung Song,* Young-Woock Noh,* Yong Taik Lim SKKU Advanced Institute of Nanotechnology (SAINT), School of Chemical Engineering, Sungkyunkwan University, Suwon, South Korea *These authors contributed equally tothis work Abstract: Effective induction of an antigen-specific cytotoxic T lymphocyte (CTL) immune response is one of the key goals of cancer immunotherapy. We report the design and fabrication of polyethylenimine (PEI)-coated polymer nanoparticles (NPs) as efficient antigen-delivery carriers that can induce antigen cross-presentation and a strong CTL response. After synthesis of poly(d,l-lactide-co-glycolide) (PLGA) NPs containing ovalbumin (OVA) by the double-emulsion solvent-evaporation method, cationic-charged PLGA NPs were generated by coating them with PEI. In a methyl tetrazolium salt assay, no discernible cytotoxic effect of PEI-coated PLGA (OVA) NPs was observed. The capacity and mechanism of PEI-coated PLGA (OVA) NPs for antigen delivery and cross-presentation on dendritic cells (DCs) were determined by fluorescence microscopy and flow cytometry. PEI-coated PLGA (OVA) NPs were internalized efficiently via phagocytosis or macropinocytosis in DCs and induced efficient cross-presentation of the antigen on MHC class I molecules via both endosome escape and a lysosomal processing mechanism. The DCs treated with PEI-coated PLGA (OVA) NPs induced a release of IL-2 cytokine from OVA-specific CD8-OVA1.3 T cells more efficiently than DCs treated with PLGA (OVA) NPs. Therefore, the PEI-coated PLGA (OVA) NPs can induce antigen cross-presentation and are expected to be used for induction of a strong CTL immune response and for efficient anticancer immunotherapy. Keywords: antigen delivery, dendritic cells, polymer NPs, vaccine, cross-presentation

Old chemistry for novel materials: Self-fluorescent high-relaxivity T(2)-weighted magnetic resonance imaging (MRI) contrast agents are produced. They are a novel type of MR/optical dual-modality in vivo imaging nanoprobe using glutaraldehyde crosslinking chemistry, and they are used to label and monitor therapeutic cells both in vitro and in vivo.

The microstructural properties of AlN layers grown on a Si(1 1 1) substrate were studied in detail using transmission electron microscope techniques to determine phase transition behaviors. AlN layers were grown in the wurtzite (WZ) and zinc-blende (ZB) polytypes. The dominant phase of AlN was transformed from a ZB structure to a WZ structure as the substrate temperature increased. Many protrusions were observed on the surfaces of AlN layers, and their density was decreased with an increase in the substrate temperature; these protrusions originated from the WZ structure of AlN and not the ZB structure. In our experiment, WZ-AlN grains were frequently observed at the edge and/or on the surface of the ZB-AlN grains at relatively low substrate temperatures. The preferred crystallographic orientation relationships of the {111} ZB-AlN ‖{111} Si and ZB-AlN ‖ Si between the ZB-AlN and the Si substrate and the (0001) WZ–AlN ‖(111) Si and [1210] WZ-AlN //[11()0] Si between WZ-AlN and the Si substrate were identified in our experiment.

An easy but robust strategy for the synthesis of bioderived polyelectrolyte nanogels for protein antigen loading and vaccine adjuvant systems that can improve both humoral (Th2) and cellular immunity (Th1) is presented. The synthesized polyelectrolyte nanogels promote the uptake of antigens into antigen-presenting cells and strongly induce ovalbumin-specific INF-γ producing cells, cytotoxic T cell activity, and antibody production.

Sentinel lymph node (SLN) biopsy techniques have been widely used in the diagnosis of cancer metastasis because lymph node metastasis is one of the most important prognostic signs. Indocyanine green (ICG) has potential application as a molecular imaging probe for SLN mapping due to its fluorescent properties emitting in the near-infrared (NIR) region, where light transmission through biological tissue is maximized. However, its low photostability in an aqueous solution at the physiological temperature and its rapid diffusion behavior through SLN into the second lymph node have limited its wide use in real clinical fields. In this study, we developed a new NIR imaging contrast system consisting of ICG and poly (γ-glutamic acid) (γ-PGA) polymers for efficient sentinel lymph node mapping. By a combination of clinically used ICG and the biocompatible anionic polyelectrolyte, γ-PGA, the photostabilities of aqueous ICG solutions at room and body temperatures were drastically enhanced. When the ICG/γ-PGA complex was injected subcutaneously into the front paw of a mouse, it entered the lymphatics and migrated to the axillary sentinel lymph node (SLN) within 2 min. Furthermore, the NIR fluorescent signal intensity and retention time of ICG/γ-PGA complex in lymph node were superior to those of ICG only. In addition, a histofluorescentstudy of the SLN resected under NIR imaging revealed that ICG and γ-PGA were co-localized in the lymph node.Taken together, the experimental results on the enhanced photostability and retention time of the ICG/γ-PGA complex provide strong evidence that it has promising potential for improved sentinel lymph node mapping.

Effective tracking of immunotherapeutic cells is essential for monitoring the migration of injected cells to the target tissue. Here we report the use of near-infrared (NIR) -emitting fluorescent semiconductor nanocrystals, called quantum dots (QDs), for noninvasive in vivo tracking of dendritic cell (DC) migration into lymph nodes. The effect of QDs on DC viability and maturation was systematically investigated using MTT assays and FACS analysis. We found that the labeling of DCs with QDs had no effect on DC phenotype or maturation potential. Cytokine and migration assays revealed that there were no significant changes in either cytokine production or chemokine-dependent migration of QD-labeled DCs relative to unlabeled cells; in both labeled and unlabeled cells, cytokine production and migratory capacity was increased by stimulation with lipopolysaccharide. Furthermore, QDs did not influence allogenic naive T cell activation or uptake of exogenous antigens. Notably, we also demonstrated that it was possible to track QD-labeled DCs injected into the footpad into popliteal and inguinal lymph nodes using NIR fluorescence. Taken together, our protocols establish the potential of noninvasive in vivo imaging of NIR-emitting QDs for tracking immunotherapeutic cells.

The design and synthesis of nanoparticles mimicking the key features in size, shape, and surface molecular organization of biological objects that provide danger-signals are essential in the formulation of effective vaccine. Here, multifaceted immunomodulatory nanoliposomes (denoted as “tumosomes”) that can turn tumors into vaccines and induce enhanced antitumor immune response are suggested. Multifaceted tumosomes are synthesized by assembling tumor cell membrane proteins as tumor-associated antigens with two lipid-based adjuvants as pathogen characters (i.e., monophosphoryl lipid A as a danger signal, dimethyldioctadecylammonium as a cell-invasion moiety). The enhanced antitumor immunity of tumosomes afforded by the improved antigenicity and antigen uptake efficiency is also evaluated in a tumor challenge experiment after their image-guided intralymph node injection. Tumosomes are able to provide tumor antigens and molecular adjuvants for the priming of a long-term adaptive immune response in tumor draining lymph nodes, as well as in the spleen. Tumosome injection leads to an inhibition of tumor growth, and the survival rate of mice treated with the tumosomes is higher than those of other groups. Taken together, the tumosomes are expected to be used for the reshaping the immune response in the lymph node and enhanced antitumor immunity.

The ability to manipulate small fluid droplets, colloidal particles and single cells with the precision and parallelization of modern-day computer hardware has profound applications for biochemical detection, gene sequencing, chemical synthesis and highly parallel analysis of single cells. Drawing inspiration from general circuit theory and magnetic bubble technology, here we demonstrate a class of integrated circuits for executing sequential and parallel, timed operations on an ensemble of single particles and cells. The integrated circuits are constructed from lithographically defined, overlaid patterns of magnetic film and current lines. The magnetic patterns passively control particles similar to electrical conductors, diodes and capacitors. The current lines actively switch particles between different tracks similar to gated electrical transistors. When combined into arrays and driven by a rotating magnetic field clock, these integrated circuits have general multiplexing properties and enable the precise control of magnetizable objects.

Honokiol (HK), a novel plant-derived natural product, is a physiologically activated compound with polyphenolic structure, and has been identified to function as an anticancer agent. It has been widely used in several diseases as a traditional medicine for a long time. We investigated whether HK could show anticancer effects on two oral squamous cell lines (OSCCs), HN-22 and HSC-4. We demonstrated that HK-treated cells showed dramatic reduction in cell growth and apoptotic cell morphologies. Intriguingly, the transcription factor specificity protein 1 (Sp1) was significantly inhibited by HK in a dose-dependent manner. Furthermore, we checked changes in cell cycle regulatory proteins and anti-apoptotic proteins at the molecular level, which are known as Sp1 target genes. The important key regulators in the cell cycle such as p27 and p21 were up-regulated by HK-mediated down-regulation of Sp1, whereas anti-apoptotic proteins including Mcl-1 and survivin were decreased, resulting in caspase-dependent apoptosis. Taken together, results from this study suggest that HK could modulate Sp1 transactivation and induce apoptotic cell death through the regulation of cell cycle and suppression of anti‑apoptotic proteins. In addition, HK may be used in cancer prevention and therapies to improve the clinical outcome as an anticancer drug.

A uridine-quantum dot conjugate, a contrast agent for multimodal imaging, was synthesized. Its T(1) relaxivity was 655 and 571.2 mM(-1) s(-1) per particle at 36 °C in phosphate buffered saline at 60 and 200 MHz, respectively. In vitro multimodal images confirmed its uptake by RAW 264.7 cells.

pH-stimuli-responsive near-infrared optical imaging nanoprobes are designed and synthesized in this study in a facile one-step synthesis process based on the use of the biocompatible and biodegradable polymer poly(γ-glutamic acid) (γ-PGA)/poly(β-amino ester) (PBAE). PBAE has good transfection efficiency and promotes degradation properties under acidic conditions. This pH-responsive degradability can be used for the effective release of encapsulating materials after cellular uptake. As an optical imaging probe, indocyanine green (ICG) is an FDA-approved near-infrared fluorescent dye with a quenching property at a high concentration. In this regard, we focus here on the rapid degradation of PBAE in an acidic environment, in which the nanoparticles are disassembled. This allows the ICG dyes to show enhanced fluorescence signals after being releasing from the particles. We demonstrated this principle in cellular uptake experiments. We expect that the developed pH-stimuli-responsive smart nanoprobes can be applied in intracellular delivery signaling applications.

We report the fabrication of a one-pot antigen system that delivers antigen to dendritic cells (DCs) and tracks their in vivo migration after injection. Multifunctional polymer nanoparticles containing ovalbumin protein, magnetic resonance imaging contrast agents (iron oxide nanoparticles), and near-infrared fluorophores (indocyanine green, ICG), MPN-OVA, were prepared using a double emulsion method. The MPN-OVA was efficiently taken up by the dendritic cells and subsequently localized in the lysosome. Flow cytometry analysis revealed an increase in the uptake of OVA antigen by MPN-OVA at 37 °C, when compared with soluble OVA protein. We found that MPN-OVA had no effect on DC surface expression of MHC class I, costimulatory (CD80, CD86) or adhesion (CD54) molecules or the ability of DCs to mature in response to LPS. Following the uptake of MPN-OVA, exogenous OVA antigen was delivered to the cytoplasm, and OVA peptides were presented on MHC class I molecules, which enhanced OVA antigen-specific cross-presentation to OT-1 T cells and CD8OVA1.3 T cell hybridoma in vitro. The immunization of mice with MPN-OVA-treated DCs induced OVA-specific CTL activity in draining lymph nodes. The presence of MPN allowed us to monitor the migration of DCs via lymphatic drainage using NIR fluorescence imaging, and the homing of DCs into the lymph nodes was imaged using MRI. This system has potential for use as a delivery system to induce T cell priming and to image DC-based immunotherapies.

Multimodal imaging contrast agents with unique magnetic resonance (MR) and optical imaging capabilities have great potentials in the diagnosis and therapy of disease. Using a rational materials design approach, the bimodal imaging contrast agent, perfluorodecalin (PFD)/[InGaP/ZnS quantum dots (QDs)] composite nanoemulsions is developed in this study. 19 F molecules in the PFD/[InGaP/ZnS QDs] nanoemulsions provide a 19 F-based MR imaging capability, while fluorescent QDs dispersed in PFD nanodroplets provide an optical imaging modality. This study also demonstrates that these bimodal imaging contrast agents can be delivered easily into both phagocytic and nonphagocytic immune cells. Internalization of multifunctional PFD/[InGaP/ZnS QDs] nanoemulsions into immunotherapeutic cells permits the labeled cells to be imaged by both magnetic resonance and fluorescence imaging with little effect on cell viability and function. The results of our study highlight the potential of PFD/[InGaP/ZnS QDs] nanoemulsion as a bimodal imaging nanoprobe for molecular imaging in immune cell-based cancer therapies.

Here, we describe the fabrication of multispectrally encoded nanoprobes, perfluorocarbon (PFC)/quantum dots (QDs) nanocomposite emulsions, which could provide both multispectral MR and multicolor optical imaging modalities. Our strategy exploited the combination of the multispectral MR properties of four different PFC materials and the multicolor emission properties of three different colored CdSe/ZnS QDs. The PFC/QDs nanocomposite emulsions were fabricated by exchanging hydrophobic ligands coated onto CdSe/ZnS QDs using 1H,1H,2H,2H-perfluorooctanethiol, which renders the QDs to be dispersible in the PFC liquids. To provide biocompatibility, the PFC liquids containing QDs were emulsified into aqueous solutions with the aid of phospholipids. The distinct (19)F-based MR images of PFC/QDs nanocomposite emulsions were obtained by selective excitation of the nanocomposite emulsions with magnetic resonance frequency of each PFC, while a specific fluorescence image of them could be selected using appropriate optical filters. The uptake of PFC/QDs nanocomposite emulsions was high in phagocytic cells such as macrophages (90.55%) and dendritic cells (85.34%), while it was low in nonphagocytic T cells (33%). We have also shown that the nanocomposite emulsions were successfully applied to differentially visualize immunotherapeutic cells (macrophages, dendritic cells, and T cells) in vivo. The PFC/QDs nanocomposite emulsions are expected to be a promising multimodality nanoprobe for the multiplexed detection and imaging of therapeutic cells both in vitro and in vivo.

This study describes the development of near-infrared optical imaging technology for the monitoring of immunotherapeutic cell-based cancer therapy using natural killer (NK) cells labeled with fluorescent nanocrystals. Although NK cell-based immunotherapeutic strategies have drawn interest as potent preclinical or clinical methods of cancer therapy, there are few reports documenting the molecular imaging of NK cell-based cancer therapy, primarily due to the difficulty of labeling of NK cells with imaging probes. Human natural killer cells (NK92MI) were labeled with anti-human CD56 antibody-coated quantum dots (QD705) for fluorescence imaging. FACS analysis showed that the NK92MI cells labeled with anti-human CD56 antibody-coated QD705 have no effect on the cell viability. The effect of anti-human CD56 antibody-coated QD705 labeling on the NK92MI cell function was investigated by measuring interferon gamma (IFN-gamma) production and cytolytic activity. Finally, the NK92MI cells labeled with anti-human CD56 antibody-coated QD705 showed a therapeutic effect similar to that of unlabeled NK92MI cells. Images of intratumorally injected NK92MI cells labeled with anti-human CD56 antibody-coated could be acquired using near-infrared optical imaging both in vivo and in vitro. This result demonstrates that the immunotherapeutic cells labeled with fluorescent nanocrystals can be a versatile platform for the effective tracking of injected therapeutic cells using optical imaging technology, which is very important in cell-based cancer therapies.

Several myeloid leukemia-derived cells have been reported to possess the ability to differentiate into dendritic cells (DC). MUTZ-3, a myeloid leukemia cell line, responds to GM-CSF, IL-4 and TNF-alpha, and acquires a phenotype similar to immature monocyte-derived DC (MoDC). In the present study, MUTZ-3-derived DC (MuDC) showed high level expression of HLA class II molecules, CD80 and CD86, and were able to function as potent antigen presenting cells as previously reported. Interestingly, MuDC maturation was induced by CD40- mediated stimulation, but not by LPS stimulation. We analyzed CCR1, CCR7 and Toll-like receptor (TLR) expressions in MuDC, and measured IL-10 and IL-12 production after maturation stimuli. Although MuDC expressed the mRNA for TLR4, a major component of the LPS receptor system, they did not show an enhanced level of CCR7 or cytokine production after LPS stimulation. In contrast, they responded to CD40 stimulation, which resulted in increased levels of CD83, CD86 and CCR7. Moreover, while LPS- stimulated MoDC could potently stimulate NK cells in a DC-NK cell co-culture, LPS-stimulated MuDC failed to stimulate primary NK cells. Taken together, our findings suggest that, although MuDC express TLR4, unlike TNF-alpha and IL-1beta, LPS does not stimulate MuDC to acquire mature phenotypes, and they may have impaired activity to initiate innate immune response.

Immunization with dendritic cells (DCs) pulsed with tumor antigen can activate tumor-specific cytotoxic T lymphocytes (CTL), which is responsible for tumor protection and regression. In this study, we examined whether DCs pulsed with necrotic tumor lysates can efficiently prevent malignant melanoma tumor cell metastasis to the lung. DCs derived from mouse bone marrow were found to produce remarkably elevated levels of IL-12 after being pulsed with the tumor lysates. Moreover, immunization with these DCs induced CTL activation and protected mice from metastasis development by intravenously inoculated tumor cells. In addition, these DCs activated NK cells in vitro in a contact-dependent manner, and induced NK activities in vivo. Furthermore, NK cell depletion before DC vaccination significantly reduced the tumor-specific CTL activity, IFN-gamma production, and IFN-gamma- inducible gene expression, and eventually interfered with the antitumor effect of tumor-pulsed DCs. Finally, similar findings with respect to NK cell dependency were obtained in the C57BL/ 6J-bg/bg mice, which have severe deficiency in cytolytic activity of NK cells. These data suggest that the antitumor effect elicited by DC vaccination, at least in a B16 melanoma model, requires the participation of both cytolytic NK and CD8(+) T cells. The findings of this study would provide important data for the effective design of DC vaccines for cancer immunotherapy.

Immunotherapy is regarded as a method of attractive treatment for cancer. Especially, dendritic cells (DCs) represent important targets for cell-mediated immunotherapy in cancer because they can capture tumor antigens that are released from tumor cells and migrate to the tumor-draining lymph nodes, where they present the antigens to T cells and secrete the pro-inflammatory cytokines that enhance T cell activation. However, immunosuppressive factors, such as signal transducer and activator of transcription-3 (STAT3), represent a major limitation for DCs-based cancer therapies. In this study, we have designed and synthesized an immunomodulatory hybrid nanoconjugates (HNC) system based on polymer nanocomposites containing quantum dots (QDs; as imaging tracers) that are decorated with CpG ODNs (as a TLR9 ligand) and STAT3 siRNAs (as an immunosuppressive gene silencer) for the efficient immunotherapeutic cancer therapy. These HNC efficiently targeted immune cells, induced TLR activation, and silenced immunosuppressive genes. Simultaneous in vivo delivery of STAT3 siRNA and CpG ODN to DCs in the tumor microenvironment induced both the inhibition of STAT3 and activation of DCs by CpG ODNs, and synergistically elicited anti-tumor effects. By using NIR-emitting QDs, the migration of in vivo DCs to lymph nodes was also tracked by real-time NIR fluorescence imaging. In the future, these studies are expected to facilitate the development of immune cell-based cancer therapy.

Although dendritic cells have important roles in cancer immunotherapy, their therapeutic efficiencies were limited due to the presence of immunosuppressive factors. Here, we report the fabrication and use of polymer nanoparticles for the simultaneous delivery of antigens and small interference RNA (siRNA) of immune suppressor genes into dendritic cells. The polymer nanoparticles containing ovalbumin (OVA, as a model antigen) and siRNA of suppressor of cytokine signaling 1 (SOCS1) were fabricated by double emulsion solvent evaporation method. The encapsulation of siRNA was about 57.6 % when OVA was present during the preparation, while that was only 2 % without the OVA. The polymer nanoparticles containing OVA and siRNA of SOCS1 were efficiently taken up by the dendritic cells and showed no detectable toxicity. The knockdown of SOCS1 genes in dendritic cells induced pro-inflammatory and anti-inflammatory cytokine expression. The polymer nanoparticles are expected to be potent nanotechnology platform for targeted delivery of siRNA and antigens into dendritic cells, and use as CD8+ T cells-based cancer immunotherapy.

A novel type of bimodal imaging nanoprobe based on (19)F-based magnetic resonance imaging and near-infrared optical imaging has been synthesized and applied for the labeling and imaging of dendritic cells both in vitro and in vivo.

We describe the development of hollow-type gold nanoparticles (NPs) for the photonic-based imaging and therapy of macrophage cells. The strong light-absorption and light-scattering properties of gold NPs render them to be useful as molecular imaging agents as well as therapeutic moieties. By controlling the geometry of the gold NPs, the optical resonance peak was shifted to around the near-infrared (NIR) region, where light transmission through biological tissue is known to be fairly high. Hollow-type gold NPs modified with dextran were phagocytosed by macrophage cells. Using dark-field microscopy, it was possible to image macrophage cells targeted with NPs. After NIR irradiation, macrophages labeled with NPs were selectively destroyed by the photothermal effect. FACS analysis revealed that the photothermal effect caused principally late apoptosis-related cell death or secondary necrosis. The experimental results showed that hollow-type gold NPs conjugated with dextran could be used not only as optical imaging contrast agents but also as a component of a novel anti-macrophage therapeutic strategy.

Dendritic cells (DC) are professional antigen-presenting cells in the immune system and can induce T cell response against virus infections, microbial pathogens, and tumors. Therefore, immunization using DC loaded with tumor-associated antigens (TAAs) is a powerful method of inducing anti-tumor immunity. For induction of effective anti-tumor immunity, antigens should be efficiently introduced into DC and presented on MHC class I molecules at high levels to activate antigen-specific CD8 + T cells. We have been exploring methods for loading exogenous antigens into APC with high efficiency of Ag presentation. In this study, we tested the effect of the cationic liposome (Lipofectin) for transferring and loading exogenous model antigen (OVA protein) into BM-DC. Methods: Bone marrow-derived DC (EM-DC) were incubated with OVA-Lipofectin complexes and then co-cultured with B3Z cells. B3Z activation, which is expressed as the amount of β-galactosidase induced by TCR stimulation, was determined by an enzymatic assay using β-gal assay system. C57BL/6 mice were immunized with OVA-pulsed DC to monitor the in vivo vaccination effect. After vaccination, mice were inoculated with EG7-OVA tumor cells. Results: BM-DC pulsed with OVA-Lipofectin complexes showed more efficient presentation of OVA-peptide on MHC class I molecules than soluble OVA-pulsed DC. OVA-Lipofectin complexes-pulsed DC pretreated with an inhibitor of MHC class I-mediated antigen presentation, brefeldin A, showed reduced ability in presenting OVA peptide on their surface MHC class I molecules. Finally, immunization of OVA-Lipofectin complexes-pulsed DC protected mice against subsequent tumor challenge. Conclusion: Our data provide evidence that antigen-loading into DC using Lipofectin can promote MHC class I- restricted antigen presentation. Therefore, antigen-loading into DC using Lipofectin can be one of several useful tools for achieving efficient induction of antigen-specific immunity in DC-based immunotherapy.