A Novel Therapy for Melanoma Developed in Mice: Transformation of Melanoma into Dendritic Cells with Listeria monocytogenes

Listeria monocytogenes is a gram-positive bacteria and human pathogen widely used in cancer immunotherapy because of its capacity to induce a specific cytotoxic T cell response in tumours. This bacterial pathogen strongly induces innate and specific immunity with the potential to overcome tumour induced tolerance and weak immunogenicity. Here, we propose a Listeria based vaccination for melanoma based in its tropism for these tumour cells and its ability to transform in vitro and in vivo melanoma cells into matured and activated dendritic cells with competent microbicidal and antigen processing abilities. This Listeria based vaccination using low doses of the pathogen caused melanoma regression by apoptosis as well as bacterial clearance. Vaccination efficacy is LLO dependent and implies the reduction of LLO-specific CD4+ T cell responses, strong stimulation of innate pro-inflammatory immune cells and a prevalence of LLO-specific CD8+ T cells involved in tumour regression and Listeria elimination. These results support the use of low doses of pathogenic Listeria as safe melanoma therapeutic vaccines that do not require antibiotics for bacterial removal

Predator-prey relationships between Molva macrophthalma and Gadiculus argenteus: the role of prey size, ontogenetic and bathymetric variations

Molva macrophthalma (Osteichthyes, Class Actinopterygii) is a demersal species restricted to the northeastern Atlantic Ocean, from the southern Bay of Biscay south to the Mediterranean Sea, whose diet is based on crustaceans and other fishes. Silvery pout (Gadiculus argenteus) is a bentho-pelagic species considered to be a forage fish, with broad geographic distribution and high abundance. Data come from the demersal trawl surveys carried out by the Instituto Español de Oceanografía (IEO) each autumn since 1983 across the southern Bay of Biscay. Total biomass, abundance and size structure of both species were recorded by haul. Stomach contents of Molva macrophthalma were also collected from 1992 to 2015. Size structure of G. argenteus was recorded both in the ecosystem and in the stomachs. More than 90 % of Molva macrophthalma diet was composed by Gadiculus argenteus showing a clear dependence on this food resource. Most of the variations in M. macrophthalma feeding behaviour were a function of prey availability and were dependent on the density of G. argenteus in the ecosystem

Spatial distribution patterns and population structure of the bluemouth Helicolenus dactylopterus (Delaroche, 1809) in the southern Bay of Biscay

Spatial distribution patterns of the bluemouth Helicolenus dactylopterus were analysed, using a spatial and temporal approach. H. dactylopterus is a worldwide distributed demersal fish with traditionally low commercial value in the study area. However, its economic importance has increased during the last 15 years in the north of Spain. Data come from Demersales Surveys (IBTS) carried out by IEO every autumn since 1983. A stratified sampling scheme was used with 5 geographical sectors and 3 depth strata (70-120 m, 121-200 m, 201-500 m). From each haul, number of specimens and total biomass were collected. Length structure was also recorded. Center of gravity analyses (CoG) showed significant geographic and bathymetric variations. An increasing temporal trend (in number and total biomass) was detected along the historical series. In the first 15 years the highest percentage of biomass and number was found in the westernmost part of the study area. During the past decade, an increasing frequency of occurrence was found in the Cantabrian Sea suggesting an expansion of its spatial distribution towards inner Bay of Biscay. An increased number of individuals and biomass captured in the Bay of Biscay corroborated these results. Throughout the study area, the larger abundance and biomass was detected in the deepest depth strata (201-500 m). It seems therefore, that changes observed spatially in the last decade were due to both a longitudinal expansion and a bathymetric one. Population structure and spatial distribution of juveniles have also been analyzed in order to find nursery areas