Background: 4-1BB (CD137) is a co-stimulatory receptor highly expressed on tumor reactive effector T cells and NK cells, which upon stimulation prolongs persistence of tumor reactive effector T and NK cells within the tumor and induces long-lived memory T cells. 4-1BB agonistic antibodies have been shown to induce strong anti-tumor effects that synergize with immune checkpoint inhibitors. The first generation of 4-1BB agonists was, however, hampered by dose-limiting toxicities resulting in suboptimal dose levels or poor agonistic activity.
View Article and Find Full Text PDF4-1BB (CD137) is an activation-induced costimulatory receptor that regulates immune responses of activated CD8 T and natural killer cells, by enhancing proliferation, survival, cytolytic activity, and IFNγ production. The ability to induce potent antitumor activity by stimulating 4-1BB on tumor-specific cytotoxic T cells makes 4-1BB an attractive target for designing novel immuno-oncology therapeutics. To minimize systemic immune toxicities and enhance activity at the tumor site, we have developed a novel bispecific antibody that stimulates 4-1BB function when co-engaged with the tumor-associated antigen 5T4.
View Article and Find Full Text PDFBackground: Indications with poor T-cell infiltration or deficiencies in T-cell priming and associated unresponsiveness to established immunotherapies represent an unmet medical need in oncology. CD40-targeting therapies designed to enhance antigen presentation, generate new tumor-specific T cells, and activate tumor-infiltrating myeloid cells to remodel the tumor microenvironment, represent a promising opportunity to meet this need. In this study, we present the first in vivo data supporting a role for tumor-associated antigen (TAA)-mediated uptake and cross-presentation of tumor antigens to enhance tumor-specific T-cell priming using CD40×TAA bispecific antibodies, a concept we named Neo-X-Prime.
View Article and Find Full Text PDFCervical cancer is a global public health problem and human papillomavirus (HPV) 16 accounts for approximately 50% of cases worldwide. Although there are several types of HPV therapeutic vaccines in clinical research, there are currently not approved for use in humans. We developed the fusion protein LALF-E7 (hereafter denominated CIGB550-E7) defined by a cell-penetrating peptide linked to an E7 mutein for the treatment of HPV16-associated tumors.
View Article and Find Full Text PDFOne important goal of cancer immunotherapy is to prevent and treat tumor metastasis. We have previously reported the significant antitumor effect induced by the immunization with our human papillomavirus therapeutic protein-based vaccine (LALF-E7) without adjuvant and admixed with clinically relevant adjuvants in the subcutaneous TC-1 tumor challenge model. In the present study, we evaluated the efficacy of the above mentioned vaccine formulations in controlling the hematogenous spread of TC-1 tumor cells using a more tumourigenic clone named TC-1* and other intravenous injection site less stressful than the tail vein.
View Article and Find Full Text PDFThe Drosophila cadherin-related protein Dachsous (Ds) plays a prominent role in planar cell polarity (PCP) and growth. The regulation of these two processes is based on the interaction between Ds and Fat proteins, generating an intracellular response required for tissue polarization and modulation of Hippo pathway activity. Here we have performed a comprehensive molecular study of the ds gene during larval development that has shown an unexpected complexity in its transcriptional regulation and revealed the expression of hitherto unsuspected transcripts.
View Article and Find Full Text PDFFEMS Yeast Res
November 2011
Pichia pastoris is a highly successful system for the large-scale expression of heterologous proteins, with the added capability of performing most eukaryotic post-translational modifications. However, this system has one significant disadvantage - frequent proteolytic degradation by P. pastoris proteases of heterologously expressed proteins.
View Article and Find Full Text PDFMesenchymal stem cells (MSCs) are multipotent cells that have the capacity to differentiate into various different cell lineages and can generate bone, cartilage and adipose tissue. MSCs are presently characterized using a broad range of different cell-surface markers that are not exclusive to MSCs and not sensitive to culture conditions or differentiation capacity. We show that the integrin subunits alpha10 and alpha11 of the collagen binding integrins alpha10beta1 and alpha11beta1 are expressed by human MSCs in monolayer cultures.
View Article and Find Full Text PDFDevelopment of heterologous systems to produce useful HCV vaccine candidates is an important part of HCV research. In this study different HCV structural region variants were designed to express the first 120 aa, 176 aa, 339 aa, and 650 aa of HCV polyprotein, and aa 384 to 521, or aa 384-605 or aa 384-746 of HCV E2 protein fused to the leader sequence of sucrose invertase 2 allowing the secretion of recombinant E2 proteins. Low expression levels were observed for HCV core protein (HCcAg) variants expressing the first 120 aa and 176 aa (HCcAg.
View Article and Find Full Text PDFWe have found a direct relationship between protein production in Pichia pastoris and the number of introduced synthetic genes of miniproinsulin (MPI), fused to the Saccharomyces cerevisiae pre-pro alpha factor used as secretion signal, and inserted between the alcohol oxidase 1 (AOX1) promoter and terminator sequences. Two consecutive approaches were followed to increase the number of integrated cassettes: the head-to-tail expression cassette multimerization procedure and re-transformation with a dominant selection marker. This increased expression from 19 to 250 mg l(-1) when about 11 copies have been integrated.
View Article and Find Full Text PDFA preformed gelatin matrix containing adherent rat colon carcinoma cells was transplanted subcutaneously into rats to analyze the outgrowth of the tumor and the inflammatory response. The gelatin matrix simplifies the precise localization of the tumor cells early after implantation and allows the gelatin piece with a growing tumor to be dissected for analysis in vitro, after various times in vivo. The immortalized mesenchymal progenitor cell line MPC1cE was cocultured with rat colon carcinoma cells in vivo in gelatin matrix.
View Article and Find Full Text PDFAn unstructured model based on mass balance equations for a recombinant methylotrophic yeast Pichia pastoris MutS (Methanol Utilization Slow) strain expressing the mini-proinsulin (MPI), was successfully established in quasi-steady state fed-batch fermentations with varying total quantity of biomass in a 7 l fermenter. The model describes the relationships between the total biomass and induction time, both in the batch and fed-batch phases. In addition, good correlations were obtained when the total quantity of MPI was correlated with the total biomass, demonstrating that the product of interest is associated with growth in the methanol phase.
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