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1.
Immune Netw ; 24(3): e19, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38974213

ABSTRACT

The influenza virus poses a global health burden. Currently, an annual vaccine is used to reduce influenza virus-associated morbidity and mortality. Most influenza vaccines have been developed to elicit neutralizing Abs against influenza virus. These Abs primarily target immunodominant epitopes derived from hemagglutinin (HA) or neuraminidase (NA) of the influenza virus incorporated in vaccines. However, HA and NA are highly variable proteins that are prone to antigenic changes, which can reduce vaccine efficacy. Therefore, it is essential to develop universal vaccines that target immunodominant epitopes derived from conserved regions of the influenza virus, enabling cross-protection among different virus variants. The internal proteins of the influenza virus serve as ideal targets for universal vaccines. These internal proteins are presented by MHC class I molecules on Ag-presenting cells, such as dendritic cells, and recognized by CD8 T cells, which elicit CD8 T cell responses, reducing the likelihood of disease and influenza viral spread by inducing virus-infected cell apoptosis. In this review, we highlight the importance of CD8 T cell-mediated immunity against influenza viruses and that of viral epitopes for developing CD8 T cell-based influenza vaccines.

2.
Public Health Nurs ; 41(4): 723-735, 2024.
Article in English | MEDLINE | ID: mdl-38588062

ABSTRACT

OBJECTIVE: To analyze duties, tasks, and task elements of health workers in charge of vaccination at public health centers in South Korea. DESIGN: Descriptive study using a survey. SAMPLE: Health workers in charge of vaccination for more than 1 year at 254 public health centers in South Korea. Of 631 health workers, 401 responded to the questionnaire, and 379 responses were included in the analysis after excluding 22 incomplete responses. MEASUREMENTS: The Developing A Curriculum (DACUM) workshop was conducted to identify the frequency, importance, and difficulty of duties, tasks, and task elements. RESULTS: Four duties (vaccination promotion, vaccination administration and symptom management, execution of vaccination, and vaccination education), 18 tasks, and 81 task elements were identified. "Execution of vaccination" exhibited the highest determinant coefficient. "Implementing the budget" exhibited the highest determinant coefficient among tasks, and "dealing with an emergency in the case of adverse events" exhibited the highest determinant coefficient among task elements. CONCLUSIONS: Duty, task, and task elements with high determinant coefficients have high educational needs. Education demands was higher for administrative work than for direct vaccination. Developing an educational curriculum based on DACUM results could contribute to the professional education of vaccine workers.


Subject(s)
Vaccination , Humans , Republic of Korea , Vaccination/statistics & numerical data , Surveys and Questionnaires , Male , Female , Adult , Curriculum , Health Personnel , Task Performance and Analysis , Middle Aged , Job Description
4.
Front Public Health ; 11: 1249736, 2023.
Article in English | MEDLINE | ID: mdl-38089018

ABSTRACT

Background: The risk of disasters and infectious diseases continues to persist in modern times. Children are a vulnerable group in disaster prevention and management due to their limited ability to cope on their own. Hence, the role and disaster preparedness capacity of early childhood teachers (ECTs) is vital for children's protection. Objectives: This study aims to explore how ECTs can improve their personal resilience to adapt to and overcome disasters as part of early childhood education and care (ECEC). To this end, this study examined the effects of ECTs' self-efficacy, resilience, disaster awareness, COVID-19 stress, and work-related stress on their disaster preparedness. Results: According to the outcomes of disaster preparedness of ECTs based on their general and job characteristics, full-time employees and principals scored significantly higher in work-related disaster preparedness (WrDP) compared to part-time workers and general and assistant teachers, respectively. Resilience and WrDP were identified as influencing factors of general disaster preparedness (GdP), with an explanatory power of 26.4%. GdP and self-efficacy were identified as influencing factors of WrDP, with an explanatory power of 25.7%. Discussion: According to the findings, ECTs' self-efficacy and GdP must be improved, followed by developing strategies to strengthen their resilience and WrDP. Doing so would ensure the safety and disaster preparedness of ECTs and infants who have low self-care capacity.


Subject(s)
Disaster Planning , Disasters , Child , Infant , Humans , Child, Preschool , Self Efficacy , Employment , Students
5.
Microbiol Resour Announc ; 12(6): e0018023, 2023 Jun 20.
Article in English | MEDLINE | ID: mdl-37255459

ABSTRACT

Bacillus sp. strain KICET-1, a bacterium isolated from traditional Korean soybean paste (Doenjang) at Osong, has one 4,099,652-bp DNA chromosome. The G+C content is 46.1%, and KICET-1 shares 99.64% similarity with Bacillus velezensis CR-502T (AY603658), according to phylogenetic classification based on 16S rRNA gene sequences.

6.
Mar Pollut Bull ; 189: 114734, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36842279

ABSTRACT

Microplastics (MPs) are found in every ocean and are frequently ingested by marine animals. This study analyzed MPs in the stomachs and intestines of 12 large marine animals comprising one fin whale (Balaenoptera physalus), seven finless porpoises (Neophocaena asiaeorientalis), two loggerhead turtles (Caretta caretta), one Indo-Pacific bottlenose dolphin (Tursiops aduncus), and one common dolphin (Delphinus delphis) that were stranded off the Republic of Korea between 2019 and 2021. MPs were detected with a mean abundance of 3.42 ± 3.2 items/g and were predominantly of transparent-white, fragment-shaped polypropylene smaller than 200 µm. The abundance of MPs found did not correlate with the biological information (maturity, body length) of the finless porpoises and there were no significant differences in the abundance of MPs between the stomachs and intestines. These results cannot accurately assess the impact of MPs on large marine animals, so further studies are necessary to understand how MPs can potentially affect them.


Subject(s)
Bottle-Nosed Dolphin , Common Dolphins , Porpoises , Animals , Microplastics , Plastics
7.
Immune Netw ; 22(5): e42, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36381958

ABSTRACT

Vaccination with tumor peptide epitopes associated with MHC class I molecules is an attractive approach directed at inducing tumor-specific CTLs. However, challenges remain in improving the therapeutic efficacy of peptide epitope vaccines, including the low immunogenicity of peptide epitopes and insufficient stimulation of innate immune components in vivo. To overcome this, we aimed to develop and test an innovative strategy that elicits potent CTL responses against tumor epitopes. The essential feature of this strategy is vaccination using tumor epitope-loaded nanoparticles (NPs) in combination with polyinosinic-polycytidylic acid (poly-IC) and anti-PD1 mAb. Carboxylated NPs were prepared using poly(lactic-co-glycolic acid) and poly(ethylene/maleic anhydride), covalently conjugated with anti-H-2Kb mAbs, and then attached to H-2Kb molecules isolated from the tumor mass (H-2b). Native peptides associated with the H-2Kb molecules of H-2Kb-attached NPs were exchanged with tumor peptide epitopes. Tumor peptide epitope-loaded NPs efficiently induced tumor-specific CTLs when used to immunize tumor-bearing mice as well as normal mice. This activity of the NPs significantly was increased when co-administered with poly-IC. Accordingly, the NPs exerted significant anti-tumor effects in mice implanted with EG7-OVA thymoma or B16-F10 melanoma, and the anti-tumor activity of the NPs was significantly increased when applied in combination with poly-IC. The most potent anti-tumor activity was observed when the NPs were co-administered with both poly-IC and anti-PD1 mAb. Immunization with tumor epitope-loaded NPs in combination with poly-IC and anti-PD1 mAb in tumor-bearing mice can be a powerful means to induce tumor-specific CTLs with therapeutic anti-tumor activity.

8.
Pharmaceutics ; 14(3)2022 Feb 26.
Article in English | MEDLINE | ID: mdl-35335897

ABSTRACT

The excessive production of reactive oxygen species (ROS) causes harmful effects, including biomolecular damage and inflammation. ROS due to ultraviolet rays, blue light, and fine dust harm the skin, causing urban-related aging. Therefore, a strong antioxidant that relieves oxidative stress in the skin and removes ROS is required. Idebenone (IB) is a powerful antioxidant but is poorly soluble and thus has low solubility in water, resulting in low bioavailability. In this study, IB-loaded nanoparticles (IB@NPs) were synthesized by loading IB without an organic solvent into nanoparticles that can provide high loading efficiency and stability for solubilization. Indeed, the synthesized IB@NPs exhibited long-term stability through dynamic light scattering, methylene blue staining, and redispersion assays, and IB@NPs prepared with a 5 wt% IB loading content were found to be optimal. The antioxidant activity of IB@NPs evaluated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay was significantly higher than that of unloaded IB. In addition, IB@NPs showed excellent biocompatibility, inhibited oxidative damage to mouse NIH-3T3 fibroblasts, and reduced intracellular ROS generation according to an in vitro DPPH antioxidant assay. Most notably, IB@NPs significantly promoted wound healing in vitro, as demonstrated by scratch assays. Therefore, as carriers with excellent stability, IB@NPs have potential cosmetic and pharmaceutical applications.

9.
BMC Microbiol ; 21(1): 76, 2021 03 08.
Article in English | MEDLINE | ID: mdl-33685392

ABSTRACT

BACKGROUND: Anthrax and smallpox are high-risk infectious diseases, and considered as potential agents for bioterrorism. To develop an effective countermeasure for these diseases, we constructed a bivalent vaccine against both anthrax and smallpox by integrating a gene encoding protective antigen (PA) of Bacillus anthracis to the genome of the attenuated vaccinia virus strain, KVAC103. RESULTS: Immunization with this bivalent vaccine induced antibodies against both PA and vaccinia virus in a mouse model. We also observed that the efficacy of this vaccine can be enhanced by combined immunization with immunoadjuvant-expressing KVAC103. Mouse groups co-immunized with PA-expressing KVAC103 and either interleukin-15 (IL-15) or cholera toxin subunit A (CTA1)-expressing KVAC103 showed increased anti-PA IgG titer and survival rate against B. anthracis spore challenge compared to the group immunized with PA-expressing KVAC103 alone. CONCLUSIONS: We demonstrated that the attenuated smallpox vaccine KVAC103 is an available platform for a multivalent vaccine and co-immunization of immunoadjuvants can improve vaccine performance.


Subject(s)
Anthrax/prevention & control , Smallpox/prevention & control , Vaccines, Combined/immunology , Vaccinia virus/immunology , Adjuvants, Immunologic , Animals , Antibodies, Bacterial/blood , Antibodies, Viral/blood , Bacillus anthracis/genetics , Mice , Vaccines, Attenuated/genetics , Vaccines, Attenuated/immunology , Vaccines, Combined/standards , Vaccines, Synthetic/immunology , Vaccinia virus/genetics
10.
Immune Netw ; 21(6): e44, 2021 Dec.
Article in English | MEDLINE | ID: mdl-35036031

ABSTRACT

Tumor peptides associated with MHC class I molecules or their synthetic variants have attracted great attention for their potential use as vaccines to induce tumor-specific CTLs. However, the outcome of clinical trials of peptide-based tumor vaccines has been disappointing. There are various reasons for this lack of success, such as difficulties in delivering the peptides specifically to professional Ag-presenting cells, short peptide half-life in vivo, and limited peptide immunogenicity. We report here a novel peptide vaccination strategy that efficiently induces peptide-specific CTLs. Nanoparticles (NPs) were fabricated from a biodegradable polymer, poly(D,L-lactic-co-glycolic acid), attached to H-2Kb molecules, and then the natural peptide epitopes associated with the H-2Kb molecules were exchanged with a model tumor peptide, SIINFEKL (OVA257-268). These NPs were efficiently phagocytosed by immature dendritic cells (DCs), inducing DC maturation and activation. In addition, the DCs that phagocytosed SIINFEKL-pulsed NPs potently activated SIINFEKL-H-2Kb complex-specific CD8+ T cells via cross-presentation of SIINFEKL. In vivo studies showed that intravenous administration of SIINFEKL-pulsed NPs effectively generated SIINFEKL-specific CD8+ T cells in both normal and tumor-bearing mice. Furthermore, intravenous administration of SIINFEKL-pulsed NPs into EG7.OVA tumor-bearing mice almost completely inhibited the tumor growth. These results demonstrate that vaccination with polymeric NPs coated with tumor peptide-MHC-I complexes is a novel strategy for efficient induction of tumor-specific CTLs.

11.
Mar Pollut Bull ; 159: 111514, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32768675

ABSTRACT

Marine pollution caused by plastic litter can threaten the survival and health of marine organisms. In 2019, a juvenile fin whale (Balaenoptera physalus, length: 13.02 m, weight 12,000 kg) was found dead floating on the sea near Jeju Island, Republic of Korea. During the dissection, 45 plastic particles were found in the body of the whale, including fishing lines, plastic filaments, pieces of fishing nets, and Styrofoam particles. The largest item found was a piece of fishing line (1180 mm in length and 1.15 mm in thickness). Filaments, both bundled and separated, were more frequent. Some of the filaments found were entangled with the baleen plate bristles. These observations suggest that plastic pollution is a potential risk for baleen whale species. This is the first record of plastic ingestion by a vulnerable baleen whale species in the sea off East Asia.


Subject(s)
Fin Whale , Animals , Asia , Asia, Eastern , Plastics , Republic of Korea
12.
Sci Rep ; 10(1): 10576, 2020 06 29.
Article in English | MEDLINE | ID: mdl-32601412

ABSTRACT

The global burden of bone-related diseases is increasing in the aging society; thus, improved bone targeted imaging for their early identification and treatment are needed. In this study, we screened novel peptide ligands for hydroxyapatite, a major inorganic component of teeth and bones, and identified a peptide enabling in vivo bone targeting and real-time fluorescence bone detection. To isolate peptides highly specific for hydroxyapatite, we used negative and positive selection from a randomized 8-mer peptide phage library and identified hydroxyapatite-specific peptides (HA-pep2, HA-pep3, and HA-pep7). Among these three peptides, HA-pep3 showed the highest binding capacity and superior dissociation constant towards hydroxyapatite surfaces over time (~ 88.3% retained on hydroxyapatite after two weeks). Furthermore, HA-pep3 was highly specific for hydroxyapatite compared to other calcium salt-based materials. Using this superior specificity, HA-pep3 showed higher accumulation in skull, spine, and joints in comparison with scrambled control peptide during real-time whole-body imaging. Ex vivo analysis of the major organs and bone from mice demonstrated that the fluorescence intensity in bone was about 3.32 folds higher in the case of HA-pep3 than the one exhibited by the scrambled control peptide. Our study identified a novel approach for targeting ligands for bone specific imaging and can be useful for drug delivery applications.


Subject(s)
Bone and Bones/diagnostic imaging , Bone and Bones/metabolism , Durapatite/chemistry , Amino Acid Sequence/genetics , Animals , Drug Delivery Systems , Durapatite/metabolism , Male , Mice , Mice, Inbred BALB C , Optical Imaging/methods , Peptide Library , Peptides/genetics , Peptides/metabolism , Tomography, X-Ray Computed/methods
13.
Chin J Nat Med ; 15(3): 192-201, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28411687

ABSTRACT

Red ginseng is a well-known alternative medicine with anti-inflammatory activity. It exerts pharmacological effects through the transformation of saponin into metabolites by intestinal microbiota. Given that intestinal microflora vary among individuals, the pharmacological effects of red ginseng likely vary among individuals. In order to produce homogeneously effective red ginseng, we prepared probiotic-fermented red ginseng and evaluated its activity using a dextran sulfate sodium (DSS)-induced colitis model in mice. Initial analysis of intestinal damage indicated that the administration of probiotic-fermented red ginseng significantly decreased the severity of colitis, compared with the control and the activity was higher than that induced by oral administration of ginseng powder or probiotics only. Subsequent analysis of the levels of serum IL-6 and TNF-α, inflammatory biomarkers that are increased at the initiation stage of colitis, were significantly decreased in probiotic-fermented red ginseng-treated groups in comparison to the control group. The levels of inflammatory cytokines and mRNAs for inflammatory factors in colorectal tissues were also significantly decreased in probiotic-fermented red ginseng-treated groups. Collectively, oral administration of probiotic-fermented red ginseng reduced the severity of colitis in a mouse model, suggesting that it can be used as a uniformly effective red ginseng product.


Subject(s)
Colitis/drug therapy , Lactobacillus plantarum/metabolism , Panax/microbiology , Plant Extracts/administration & dosage , Probiotics/metabolism , Administration, Oral , Animals , Colitis/chemically induced , Colitis/immunology , Colon/drug effects , Colon/immunology , Dextran Sulfate/adverse effects , Disease Models, Animal , Female , Fermentation , Humans , Interleukin-6/immunology , Mice , Mice, Inbred BALB C , Panax/chemistry , Panax/metabolism , Plant Extracts/chemistry , Plant Extracts/metabolism , Powders/administration & dosage , Powders/metabolism , Tumor Necrosis Factor-alpha/immunology
14.
Pharm Biol ; 55(1): 317-323, 2017 Dec.
Article in English | MEDLINE | ID: mdl-27927080

ABSTRACT

CONTEXT: Red ginseng (heat-processed Panax ginseng) is a well-known alternative medicine with pharmacological antidiabetic activity. It exerts pharmacological effects through the transformation of saponin into metabolites by the intestinal microbiota. Given that intestinal conditions and intestinal microflora vary among individuals, the pharmacological effects of orally administered red ginseng likely may vary among individuals. OBJECTIVE: To overcome this variation and produce homogeneously effective red ginseng, we evaluated the antidiabetic effects of probiotic-fermented red ginseng in a mouse model. MATERIALS AND METHODS: The antidiabetic efficacy of orally administered probiotic-fermented red ginseng was assessed in ICR mice after induction of diabetes using streptozotocin (170 mg/kg body weight). Samples were given orally for 8 weeks, and indicators involved in diabetic disorders such as body weight change, water intake, blood glucose, glucose tolerance and various biochemical parameters were determined. RESULTS: Oral administration of probiotic-fermented red ginseng significantly decreased the level of blood glucose of about 62.5% in the fasting state and induced a significant increase in glucose tolerance of about 10.2% compared to the control diabetic mice. Additionally, various indicators of diabetes and biochemical data (e.g., blood glycosylated haemoglobin level, serum concentrations of insulin, and α-amylase activity) showed a significant improvement in the diabetic conditions of the mice treated with probiotic-fermented red ginseng in comparison with those of control diabetic mice. DISCUSSION AND CONCLUSION: Our results demonstrate the antidiabetic effects of probiotic-fermented red ginseng in the streptozotocin-induced mouse diabetes model and suggest that probiotic-fermented red ginseng may be a uniformly effective red ginseng product.


Subject(s)
Blood Glucose/drug effects , Diabetes Mellitus, Experimental/drug therapy , Fermentation , Hypoglycemic Agents/pharmacology , Panax/metabolism , Plant Extracts/metabolism , Plant Extracts/pharmacology , Probiotics , Streptozocin , Administration, Oral , Animals , Biomarkers/blood , Blood Glucose/metabolism , Diabetes Mellitus, Experimental/blood , Diabetes Mellitus, Experimental/chemically induced , Glycated Hemoglobin/metabolism , Hypoglycemic Agents/administration & dosage , Hypoglycemic Agents/metabolism , Insulin/blood , Male , Mice, Inbred ICR , Phytotherapy , Plant Extracts/administration & dosage , Plants, Medicinal , Powders , Time Factors , alpha-Amylases/metabolism
15.
Dermatol Surg ; 42(7): 883-92, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27286415

ABSTRACT

BACKGROUND: In East Asian countries, hair transplantation is a quite common procedure for treating pattern hair loss, cosmetically correcting the hairline, and correcting eyebrow and pubic hair defects. Although there are general guidelines concerning hair transplantation, certain factors need to be addressed to make the guidelines more specific and suitable to East Asian requirements. OBJECTIVE: To provide guidelines for hairline design, donor harvesting, graft preparation and placement, and medical treatment that are appropriate for hair transplantation in East Asian patients. METHODS: Recommendations are based on the experience of the authors, surgeons who perform hair transplantation, and a comprehensive review of the available literature on hair transplantation in East Asians. RESULTS: Data on hair thickness and graft density, hairline design, and graft creation and placement techniques have been collaboratively evaluated and used to establish overall guidelines. CONCLUSION: The use of the proposed guidelines by surgeons will hopefully enhance outcomes and bring greater consistency to hair transplantation procedures for East Asian patients.


Subject(s)
Asian People , Cosmetic Techniques/standards , Hair/transplantation , Tissue and Organ Harvesting/methods , Dermatologic Agents/therapeutic use , Eyebrows/transplantation , Asia, Eastern , Female , Finasteride/therapeutic use , Humans , Male , Minoxidil/therapeutic use , Practice Guidelines as Topic , Transplantation/methods
16.
Angle Orthod ; 86(5): 804-9, 2016 Sep.
Article in English | MEDLINE | ID: mdl-26756375

ABSTRACT

OBJECTIVE: To ascertain the dimensional accuracies of some commonly used ceramic self-ligation brackets and the amount of torsional play in various bracket-archwire combinations. MATERIALS AND METHODS: Four types of 0.022-inch slot ceramic self-ligating brackets (upper right central incisor), three types of 0.018-inch ceramic self-ligating brackets (upper right central incisor), and three types of rectangular archwires (0.016 × 0.022-inch beta-titanium [TMA] (Ormco, Orange, Calif), 0.016 × 0.022-inch stainless steel [SS] (Ortho Technology, Tampa, Fla), and 0.019 × 0.025-inch SS (Ortho Technology)) were measured using a stereomicroscope to determine slot widths and wire cross-sectional dimensions. The mean acquired dimensions of the brackets and wires were applied to an equation devised by Meling to estimate torsional play angle (γ). RESULTS: In all bracket systems, the slot tops were significantly wider than the slot bases (P < .001), yielding a divergent slot profile. Clarity-SLs (3M Unitek, Monrovia, Calif) showed the greatest divergence among the 0.022-inch brackets, and Clippy-Cs (Tomy, Futaba, Fukushima, Japan) among the 0.018-inch brackets. The Damon Clear (Ormco) bracket had the smallest dimensional error (0.542%), whereas the 0.022-inch Empower Clear (American Orthodontics, Sheboygan, Wis) bracket had the largest (3.585%). CONCLUSIONS: The largest amount of theoretical play is observed using the Empower Clear (American Orthodontics) 0.022-inch bracket combined with the 0.016 × 0.022-inch TMA wire (Ormco), whereas the least amount occurs using the 0.018 Clippy-C (Tomy) combined with 0.016 × 0.022-inch SS wire (Ortho Technology).


Subject(s)
Dental Alloys , Orthodontic Appliance Design , Orthodontic Brackets , Orthodontic Wires , Ceramics , Cross-Sectional Studies , Dental Stress Analysis , Friction , Humans , Japan , Materials Testing , Stainless Steel
17.
Biosens Bioelectron ; 64: 69-73, 2015 Feb 15.
Article in English | MEDLINE | ID: mdl-25194798

ABSTRACT

Francisella (F.) tularensis causes the zoonotic disease tularemia and categorized as one of the highest-priority biological agents. The sensing approaches utilized by conventional detection methods, including enzyme-linked immunosorbent assay (ELISA), are not sensitive enough to identify an infectious dose of this high-risk pathogen due to its low infective dose. As an attempt to detect F. tularensis with high sensitivity, we utilized the highly sensitive immunoassay system named gold nanoparticle-based oligonucleotide-linked immunosorbent assay (GNP-OLISA) which uses antibody-gold nanoparticles conjugated with DNA strands as a signal generator and RNA oligonucleotides appended with a fluorophore as a quencher for signal amplification. We modified the GNP-OLISA for the detection F. tularensis to utilize one antibody for both the capture of the target and for signal generation instead of using two different antibodies, which are usually employed to construct the antibody sandwich in the ELISA. The GNP-OLISA showed 37-fold higher sensitivity compared with ELISA and generated very consistent detection results in the sera. In addition, the detection specificity was not affected by the presence of non-target bacteria, suggesting that GNP-OLISA can be used as a sensitive detection platform for monitoring high-risk pathogens thereby overcoming the limit of the conventional assay system.


Subject(s)
Francisella tularensis/isolation & purification , Gold/chemistry , Immobilized Nucleic Acids/chemistry , Immunoassay/methods , Immunosorbents/chemistry , Metal Nanoparticles/chemistry , Tularemia/diagnosis , Antibodies, Immobilized/chemistry , Biosensing Techniques/methods , Enzyme-Linked Immunosorbent Assay , Humans , Sensitivity and Specificity , Tularemia/microbiology
18.
Int Immunopharmacol ; 21(2): 487-93, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24957690

ABSTRACT

Myeloid-derived suppressor cells (MDSCs) mediate tumor-associated immune suppression in both cancer patients and tumor-bearing animals. Reduction or elimination of MDSCs reduces the rate of tumor progression and improves cancer therapies that employ mechanisms of immunity. Here we show that baccatin III, which is the precursor for the semisynthesis of paclitaxel, exerts anti-tumor immunomodulatory activity in very low doses (0.05-0.5mg/kg), although it is regarded as an inactive derivative of paclitaxel. Oral administration of baccatin III significantly reduced the growth of tumors induced by engrafting BALB/c mice with either 4 T1 mammary carcinoma or CT26 colon cancer cells. Baccatin III (0.5mg/kg) did not exert anti-tumor activity in athymic nude mice. Baccatin III decreased the accumulation of MDSCs in the spleens of the tumor-bearing mice. Furthermore, MDSCs isolated from baccatin III-treated mice, compared with those isolated from vehicle-treated mice, had a significantly reduced suppressive effect on T cells treated with the anti-CD3 and anti-CD28 monoclonal antibodies. Moreover, these cells produced significantly reduced amounts of reactive oxygen species and nitric oxide. These results suggest that baccatin III reduced tumor progression by inhibiting the accumulation and suppressive function of MDSCs.


Subject(s)
Alkaloids/pharmacology , Myeloid Cells/drug effects , Paclitaxel/pharmacology , Taxoids/pharmacology , Animals , Antibodies, Monoclonal/pharmacology , Antineoplastic Agents/pharmacology , Cell Line, Tumor , Colonic Neoplasms/drug therapy , Colonic Neoplasms/metabolism , Female , Male , Mammary Neoplasms, Animal/drug therapy , Mammary Neoplasms, Animal/metabolism , Mice , Mice, Inbred BALB C , Mice, Nude , Myeloid Cells/metabolism , Reactive Oxygen Species/metabolism , T-Lymphocytes/drug effects , T-Lymphocytes/metabolism
19.
Arch Pharm Res ; 37(9): 1234-40, 2014.
Article in English | MEDLINE | ID: mdl-24748512

ABSTRACT

Myeloid-derived suppressor cells (MDSCs) accumulate in cancer patients and tumor-bearing mice, subsequently suppressing the host immune system. MDSCs represent a group of immature myeloid cells expressing CD11b and Gr-1. Here, we show that a Toll-like receptor (TLR) agonist, resiquimod, which binds to TLR7 and TLR8, induces the differentiation of MDSCs into mature myeloid cells. MDSCs were isolated from mice bearing mammary carcinoma 4T1 cells, and the purified MDSCs were cultured in the presence of resiquimod for 5 days. Phenotypic analysis showed that the resiquimod-treated MDSCs differentiated into F4/80⁺ macrophages and CD11c⁺/I-A(d⁺) dendritic cells. Functional analysis showed that the MDSCs also lost their suppressive activity on T cells. Resiquimod-treated MDSCs significantly enhanced the proliferation of T cells that were treated with anti-CD3 and anti-CD28 monoclonal antibodies. These results show that resiquimod induces the differentiation of MDSCs into macrophages and dendritic cells, and also suggest that resiquimod may improve cancer immunotherapy by reducing immunosuppressive MDSCs.


Subject(s)
Antineoplastic Agents/pharmacology , Dendritic Cells/drug effects , Imidazoles/pharmacology , Immunologic Factors/pharmacology , Macrophages/drug effects , Toll-Like Receptor 7/antagonists & inhibitors , Toll-Like Receptor 8/antagonists & inhibitors , Animals , Antigens, Differentiation/metabolism , Carcinoma/immunology , Carcinoma/metabolism , Carcinoma/pathology , Cell Differentiation/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Cells, Cultured , Dendritic Cells/immunology , Dendritic Cells/metabolism , Dendritic Cells/pathology , Macrophages/immunology , Macrophages/metabolism , Macrophages/pathology , Male , Mammary Neoplasms, Experimental/immunology , Mammary Neoplasms, Experimental/metabolism , Mammary Neoplasms, Experimental/pathology , Mice, Inbred BALB C , Myeloid Progenitor Cells/drug effects , Myeloid Progenitor Cells/immunology , Myeloid Progenitor Cells/metabolism , Myeloid Progenitor Cells/pathology , Specific Pathogen-Free Organisms , Spleen/immunology , Spleen/pathology
20.
Clin Cancer Res ; 20(5): 1223-34, 2014 Mar 01.
Article in English | MEDLINE | ID: mdl-24389326

ABSTRACT

PURPOSE: Epitope-based cancer vaccines capable of inducing CD8 T-cell responses to tumor-associated antigens (TAA) expressed by tumor cells have been considered as attractive alternatives for the treatment of some types of cancer. However, reliable TAAs have not been identified for most malignant diseases, limiting the development of epitope-based vaccines. Herein, we report that the combinatorial therapy of polyinosinic-polycytidylic acid (poly-IC) and antiprogrammed death-ligand 1 (PD-L1) monoclonal antibody (mAb) can be implemented with good results for tumors where no known TAAs have been identified. EXPERIMENTAL DESIGN: Three cancer mouse models (melanoma, lung, and colon) were used to evaluate therapeutic efficacy and examine the immunologic mechanisms of the poly-IC/anti-PD-L1 mAb therapy. RESULTS: The combined administration of poly-IC and anti-PD-L1 mAb into tumor-bearing mice generated potent immune responses resulting in the complete eradication or remarkable reduction of tumor growth. In some instances, the poly-IC/anti-PD-L1 mAb therapy induced long-lasting protection against tumor rechallenges. The results indicate that CD8 T cells but not CD4 T cells or NK cells mediated the therapeutic efficacy of this combinatorial therapy. Experiments using genetically deficient mice indicate that the therapeutic efficacy of this combinatorial therapy depended in part by the participation of type-I IFN, whereas IFN-γ did not seem to play a major role. CONCLUSIONS: The overall results suggest that immunotherapy consisting of the combination of poly-IC/anti-PD-L1 mAb could be a promising new approach for treating patients with cancer, especially those instances where no reliable TAAs are available as a therapeutic vaccine.


Subject(s)
Antibodies, Monoclonal/pharmacology , B7-H1 Antigen/antagonists & inhibitors , B7-H1 Antigen/metabolism , CD8-Positive T-Lymphocytes/immunology , Neoplasms/immunology , Neoplasms/metabolism , Poly I-C/pharmacology , Animals , CD8-Positive T-Lymphocytes/metabolism , Disease Models, Animal , Female , Humans , Immunotherapy , Interferon Type I/metabolism , Interferon-gamma/metabolism , Melanoma, Experimental , Mice , Mice, Knockout , Neoplasms/drug therapy , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/metabolism
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