Optimal Growth Conditions of Microorganisms Isolated from the Buyeo Royal Tomb No. 1 and Their Effects on Painting Layers

The Buyeo Royal Tomb No. 1 is an ancient tomb built in the late 6th and early 7th century. The four walls of the main room have murals of four guardian deities, and the ceiling has murals of lotus and cloud patterns. This study assessed the optimal growth conditions of two fungal (Fusarium oxysporum, Mortierella sp.) and four bacterial (Bacillus cereus, Cupriavidus campinensis, Streptomyces avidinii, Streptomyces cirratus) strains isolated from the Tomb No. 1, along with their effects on the painting layer. The two fungi showed optimal growth at 20°C - 30°C under both nutrient and non-nutrient conditions. These strains did not decompose or discolor the three pigments (cinnabar, hematite, oyster shell white);however, M. sp. showed slight decomposition of the media (starch paste, sea weed). The four bacterial strains showed the most active growth at 20°C - 25°C under nutrient conditions and did not grow under non-nutrient conditions. These bacteria commonly degraded animal glue and sea weed components. In addition, S. cirratus degraded starch. The genus Streptomyces discolored the pigment medium to brown and black, suggesting a possible risk of discoloration of the murals. The current environment in Tomb No. 1 was sufficient for microorganism growth, and the presence of strains such as soil bacteria and actinomycetes on the mural surface may damage the murals. The findings of this study could be helpful for preserving mural tombs against biological damage caused by microorganisms that are already present or may be present in the tombs in the future. These findings also provide guidelines for comprehensive conservation management.

Optimal culture conditions for the generation of natural killer cell-induced dendritic cells for cancer immunotherapy

Dendritic cell(DC)-based vaccines continue to be considered an attractive tool for cancer immunotherapy.DCs require an additional signal from the environment or other immune cells to polarize the development of immune responses toward T helper 1(Th1)or Th2 responses.DCs play a role in natural killer(NK)cell activation,and NK cells are also able to activate and induce the maturation of DCs.We investigated the types of NK cells that can induce the maturation and enhanced function of DCs and the conditions under which these interactions occur.DCs that were activated by resting NK cells in the presence of inflammatory cytokines exhibited increased expression of several costimulatory molecules and an enhanced ability to produce IL-12p70.NK cell-stimulated DCs potently induced Th1 polarization and exhibited the ability to generate tumor antigen-specific cytotoxic T lymphocyte responses.Our data demonstrate that functional DCs can be generated by coculturing immature DCs with freshly isolated resting NK cells in the presence of Toll-like receptor agonists and proinflammatory cytokines and that the resulting DCs effectively present antigens to induce tumor-specific T-cell responses,which suggests that these cells may be useful for cancer immunotherapy.

Effect of gadolinium incorporation on optical characteristics of YNbO_4:Eu^(3+) phosphors for lamp applications

Eu3＋-doped （Y,Gd）NbO4 phosphor was synthesized by solid-state reaction for possible application in cold cathode fluorescent lamps. A broad absorption band with peak maximum at 272 nm was observed which was due to the charge transfer between Eu3＋ ions and neighboring oxygen anions. A deep red emission at the peak wavelength of 612 nm was observed which could be attributed to the 5D0→7F2 transition in Eu3＋ ions. The highest luminance for Y1-x-yGdyNbO4：Eux3＋ under 254 nm excitation was achieved at Eu3＋ concentration of 18 mol.% （x=0.18） and Gd3＋ concentration of 8.2 mol.% （y=0.082）. The luminance of Y0.738Gd0.082NbO4：Eu3＋0.18 was higher than that of a typical commercial phosphor Y2O3：Eu3＋ and the CIE chromaticity coordinate was （0.6490, 0.3506）, which was deeper than that of Y2O3：Eu3＋. The particle size of the synthesized phosphors was controlled by the NaCl flux and particle size as high as 8 μm with uniform size distribution of particles was obtained.

Identification of novel HLA-A 0201-restricted epitopes from anterior gradient-2 as a tumor-associated antigen against colorectal cancer

Anterior gradient-2 （AGR2） promotes tumor growth, cell migration and cellular transformation and its enhanced expression is almost completely restricted to malignant tissues, thus making AGR2 an interesting target for the development of immunotherapeutic strategies. We investigated whether the AGR2 molecule comprises human leukocyte antigen （HLA）-A 0201-binding epitopes recognized by human cytotoxic T lymphocytes （CTLs）, which could be targeted in dendritic cell （DC）-based cancer immunotherapy against colorectal cancer （CRC）. We reviewed the sequence of AGR2 for peptides that could potentially bind to HLA-A 0201 with the aid of a computer-based program. Five candidate peptides with different binding scores were synthesized and tested. These peptides were then assessed for their immunogenicity to elicit specific immune responses mediated by CTLs in vitro by means of enzyme-linked immunospot assays and CTL assays. AGR2 was highly expressed in several CRC cell lines, including DK01, DLD1, KM 12C, HCT-8 and HT-29. DCs pulsed with AGR2-P2 （aa 11-19; LLVALSYTL） or AGR2-P4 （aa 127-135; RIMFVDPSL） generated potent CTLs that could lyse T2 cells pulsed with AGR2-P2 or AGR2-P4 and HLA-A0201＋ AGR2-positive CRC cell lines in a strong dose-dependent and HLA-A 0201-restricted manner. In conclusion, these novel epitopes derived from AGR2 protein may be attractive candidates for DC-based immunotherapy for CRC.

Type I and II interferons enhance dendritic cell maturation and migration capacity by regulating CD38 and CD74 that have synergistic effects with TLR agonists

The major limitation for the maturation of dendritic cells(DCs)using Toll-like receptor(TLR)agonists is their decreased ability to migrate into lymph nodes compared with conventional DCs.CD38 can be used as a multifunctional marker to modulate migration,survival and Th1 responses of DCs.CD74 has been shown to negatively regulate DC migration.The goal of this study was to investigate the combinations of TLR agonists and interferons(IFNs)that most effectively regulate CD38 and CD74 expression on DCs.Synergistic TLR agonist stimulation in combination with IFN-a and IFN-c was the best method for regulating CD38 and CD74 expression and inducing the highest secretion of IL-12p70.An in vitro migration assay showed that DCs treated with this combination had significantly enhanced migratory ability,similar to that observed in cells expressing CD38,CD74 and CCR7.The results of this study suggest that an alternative maturation protocol in which two TLR ligands are combined with type I and II IFNs generates potent DCs that have both a high migratory capacity and high IL-12p70 production.