University of Siena

About: University of Siena is a education organization based out in Siena, Italy. It is known for research contribution in the topics: Population & Cancer. The organization has 12179 authors who have published 33334 publications receiving 1008287 citations. The organization is also known as: Università degli studi di Siena & Universita degli studi di Siena.

Chemotherapy-induced antitumor immunity requires formyl peptide receptor 1

Abstract: Antitumor immunity driven by intratumoral dendritic cells contributes to the efficacy of anthracycline-based chemotherapy in cancer. We identified a loss-of-function allele of the gene coding for formyl peptide receptor 1 (FPR1) that was associated with poor metastasis-free and overall survival in breast and colorectal cancer patients receiving adjuvant chemotherapy. The therapeutic effects of anthracyclines were abrogated in tumor-bearing Fpr1(-/-) mice due to impaired antitumor immunity. Fpr1-deficient dendritic cells failed to approach dying cancer cells and, as a result, could not elicit antitumor T cell immunity. Experiments performed in a microfluidic device confirmed that FPR1 and its ligand, annexin-1, promoted stable interactions between dying cancer cells and human or murine leukocytes. Altogether, these results highlight the importance of FPR1 in chemotherapy-induced anticancer immune responses.

Metasurfing: Addressing Waves on Impenetrable Metasurfaces

Abstract: Metasurfaces constitute a class of thin metamaterials, which are used from microwave to optical frequencies to create new antennas and microwave devices. Here, we propose the use of variable-impedance metasurfaces for transforming surface or guided waves into different wavefield configurations with desirable properties. We will shortly refer to this metasurface-driven wavefield transformation as “metasurfing.” Metasurfing can be obtained by an appropriate synthesis of inhomogeneous metasurface reactance that allows a local modification of the dispersion equation and, at constant operating frequency, of the local wave vector. The general effects of metasurface modulation are similar to those obtained in solid (volumetric) inhomogeneous metamaterial as predicted by the transformation optics-namely, readdressing the propagation path of an incident wave. However, significant technological simplicity is gained. Several examples are shown as a proof of concept.

Targeting by affinity-matured recombinant antibody fragments of an angiogenesis associated fibronectin isoform.

Abstract: The oncofetal fibronectin (B-FN) isoform is present in vessels of neoplastic tissues during angiogenesis but not in mature vessels. B-FN could therefore provide a target for diagnostic imaging and therapy of cancer. Phage display libraries have been used to isolate human antibody fragments with pan-species recognition of this isoform. We describe the use of these fragments in nude mice to target an aggressive tumor (grafted F9 murine teratocarcinoma). Imaging in real time was done by infrared photodetection of a chemically coupled fluorophore. The targeting was improved by use of affinity-matured fragments with low kinetic dissociation rates (koff = 1.5 x 10(-4) s-1) and also by engineering dimeric fragments via a C-terminal amphipathic helix.

Oral probiotic administration induces interleukin-10 production and prevents spontaneous autoimmune diabetes in the non-obese diabetic mouse

Abstract: Aims/hypothesis Recent observations suggest the involvement of the gastrointestinal tract in the pathogenesis of islet autoimmunity. Thus, the modulation of gut-associated lymphoid tissue may represent a means to affect the natural history of the disease. Oral administration of probiotic bacteria can modulate local and systemic immune responses; consequently, we investigated the effects of oral administration of the probiotic compound VSL#3 on the occurrence of diabetes in non-obese diabetic (NOD) mice.