Report of in vitro antileishmanial properties of Iberian macroalgae.

Here is reported the anti Leishmania infantum activity of 48 hexane, CH2Cl2 and MeOH extracts from 16 macroalgae collected on the Iberian Coast. Seven hexane and CH2Cl2 Cystoseira baccata, Cystoseira barbata, Cystoseira tamariscifolia, Cystoseira usneoides, Dictyota spiralis and Plocamium cartilagineum extracts were active towards promastigotes (IC50 29.8-101.8 µg/mL) inducing strong morphological alterations in the parasites. Hexane extracts of C. baccata and C. barbata were also active against intracellular amastigotes (IC50 5.1 and 6.8 µg/mL, respectively). Fatty acids, triacylglycerols, carotenoids, steroids and meroterpenoids were detected by nuclear magnetic resonance (NMR), and gas chromatography in the Cystoseira extracts. These results suggest that Cystoseira macroalgae contain compounds with antileishmanial activity, which could be explored as scaffolds to the development of novel sources of antiparasitic derivatives.

An alternative renewable source of squalene for use in emulsion adjuvants.

Emulsions have been used to boost immunogenicity of antigens since the discovery of complete Freunds adjuvant. Optimization to reduce reactogenicity of emulsion adjuvants lead to the development of oil in water emulsions based on squalene. MF59 is an oil-in-water emulsion that is a component of an approved influenza product in Europe. Currently MF59 is manufactured from squalene derived from an animal source. Recently a high purity plant-derived squalene source has become available at an appropriate purity for a vaccine adjuvant. The purpose of this study was to evaluate and compare animal-derived squalene and plant-derived squalene for equivalency. Nanoemulsions were prepared and analyzed for size and viscosity prepared from each source. The two emulsions were administered in two separate animal studies, one focusing on Neisseria meningitidis B, and one focusing on influenza. Readouts were ELISA titers for each antigen and serum bactericidal activity for N. meningitidis B, and hemagglutinin inhibition for influenza to see the functionality of the antibodies produced. Results indicate that there are no differences between the antibodies elicited after immunization from an emulsion made with oil derived from either an animal or plant-source.

Comparative pre-clinical evaluation of receptor tyrosine kinase inhibitors for the treatment of multiple myeloma.

BACKGROUND: Fibroblast growth factor receptor 3 (FGFR3) is up-regulated as a result of the t(4;14)(p16;q32) translocation that occurs in up to 20% of multiple myeloma (MM) patients. Recent studies have demonstrated that up-regulation of FGFR3 promotes cell survival, growth and drug resistance in malignant plasma cells, both in vitro and in vivo. Therefore, inhibition of FGFR3 signalling is potential target for the chemotherapeutic intervention in t(4;14) MM. METHODS: Small molecule receptor tyrosine kinase inhibitors (PD173074, sunitinib (SU-11248), vandetanib (ZD6474) and vatalanib (PTK-787)) with varying degrees of inhibitory activity and selectivity against FGFR, were assessed in Ba/f3 cells expressing ZNF198-FGFR1 and MM cell lines. Cell viability, FGFR3 and ZNF198-FGFR1 phosphorylation and apoptosis were evaluated by growth inhibition assays, immunoblotting and fluorescence-activated cell sorting analysis, respectively. An in vivo study was performed with sunitinib in t(4;14)-positive and t(4;14)-negative human MM tumour xenograft models. RESULTS: PD173074 and sunitinib differentially inhibited the growth of Ba/f3 cells expressing ZNF198-FGFR1 (GI(50)=10 nM and 730 nM, versus GI(50) >1 µM and 2.7 µM for parental cells; p<0.0001) and t(4;14) positive MM cell lines (GI(50)=4-10 µM and 1-3 µM, versus GI(50)=14-15 µM and 4-5 µM for t(4;14) negative MM cells; p≤0.002). In addition, both PD173074 and sunitinib inhibited the activation of FGFR3 in t(4;14)-positive MM cells. PD173074 and sunitinib induced an apoptotic response in a concentration and time-dependent manner in a t(4;14)-positive (PD174073 and sunitinib) but not a t(4;14)-negative MM cell line (sunitinib only); however, in in vivo tumours derived from the same cell lines, sunitinib was only active in the t(4;14)-negative model. CONCLUSIONS: These data demonstrate that PD173074 and sunitinib are inhibitors of FGFR3 in MM cell lines, and that sunitinib has in vivo activity in a human MM tumour xenograft model. However, caution should be exercised in using the t(4;14) translocation as a predictive biomarker for patient selection in clinical trials with sunitinib.

Acceptable levels of endotoxin in vaccine formulations during preclinical research.

This brief commentary reviews endotoxin levels of commercial vaccines and puts them into context for the preclinical researcher working in vaccines. Vaccines are not required to adhere to endotoxin levels as outlined in the United States Pharmacopoeia. Vaccine manufacturers have to show that the vaccine is safe and efficacious in clinical trials. Endotoxin limits are typically lot release specifications for most vaccines, but these values are not available to most researchers designing preclinical experiments. The limits outlined are calculated from endotoxin levels found in a variety of vaccine types such as gene vectors, recombinant subunits, polysaccharide, live attenuated, inactivated and toxoid vaccines. It is clear that certain families of vaccines such as toxoids contain much higher levels of endotoxin, where others such as purified recombinant subunits and gene vectors may contain very low levels.