Risedronate Inhibition of Matrix Metalloproteinase-2 Expression in Osteosarcoma Cell Line

Background and objective Osteosarcoma is a high-malignant bone tumor and is the most frequent malignant bone tumor in children and adolescents. Significant proportions of the

Ovalicin attenuates atopic dermatitis symptoms by inhibiting IL-31 signaling and intracellular calcium influx

Atopic dermatitis(AD)is a common skin disorder difficult to be treated with medication.This study investigated the potential of ovalicin extracted from Cordyceps militaris for the treatment of AD using in vitro and in vivo models.We found that,in canine macrophage cell line DH82,lipopolysaccharide(LPS)upregulated the expression of genes associated with inflammation and pruritic responses through activating calcium and interleukin-31(IL-31)signaling,and the upregulation could be suppressed by ovalicin,with an effect significantly stronger than dexamethasone.Ovalicin also reduced the expression of IL-31 downstream genes,including JAK2(Janus kinase 2),TRPV1(transient receptor potential vanilloid receptor-1),and HRH2(histamine receptor H2).Ovalicin significantly alleviated the allergic symptoms in the AD mouse model.Histologically,the number of macrophages and mast cells infiltrated in the dermis was significantly reduced by ovalicin treatment.In the skin tissue of AD mice,reduction of IL-31 receptor was observed in the ovalicin treated group compared to the group without ovalicin treatment.To our knowledge,this is the first study to elucidate the anti-atopic mechanism of ovalicin,which could be an alternative to steroidal drugs commonly used for AD treatment.

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.

Dendritic cell-based immunotherapy for colon cancer using an HLA-A＊0201-restricted cytotoxic T-lymphocyte epitope from tumor-associated antigen 90K

Tumor-associated antigen 90K is implicated in cell-cell and cell-extracellular matrix adhesion through its interaction with galectin-3 and integrin-β 1 and is highly expressed in malignant tissues, making it a novel target for the development of new immunotherapies. We investigated a potential immunotherapy treatment for colon cancer using 90K-specific cytotoxic T lymphocytes induced by autologous dendritic cells and pulsed with 90K peptides. We selected three peptides （90K3s1, 90K5 and 90K523） that bind to HLA-A＊0201 molecules on the basis of their binding affinity, as determined by a peptide-T2 binding assay. Dendritic cells pulsed with 90K peptides resulted in the efficient generation of mature dendritic cells and exhibited enhanced T-cell stimulation and polarization of naive T cells toward Thl. Dendritic cells pulsed with 90K peptides generated potent cytotoxic T-lymphocytes that lysed T2 cells loaded with each 90K peptide, and 90K＋/HLA-A2＋ colon cancer cell lines, including HCT116 and SW480, in a dose-dependent and HLA-A＊O2Ol-restricted manner. No killing was observed in 90K＋/HLA-A2- DLD1 or 90K-/HLA-A2- K562 cells. Therefore, we believe that cytotoxic T-lymphocytes stimulated by 90K peptide-pulsed dendritic cells naturally recognize the 90K peptide presented by colon cancer cells in the context of HLA-A2, and kill 90K-positive tumor cells. Dendritic cells pulsed with 90K peptides led to the induction of granzyme B and perforin positive CD8＋ T cells against HCT116 and SW480 cells, but not DLD1 cells. In conclusion, 90K-specific cytotoxic T lymphocytes, generated by stimulating T cells with 90K peptide-pulsed dendritic cells, could be useful effector cells for the immunotherapv treatment of colon cancer.

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.