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31 p.-4 fig.-2 tab.-1 graph. abst., Leishmaniasis is a term that encompasses a compendium of neglected tropical diseases caused by dimorphic and digenetic protozoan parasites from the genus Leishmania (Kinetoplastida: Trypanosomatidae). The clinical manifestations of neotropical cutaneous leishmaniasis (NCL) caused by Leishmania pifanoi and other species of the “Leishmania mexicana complex” mainly correspond to anergic diffuse cutaneous leishmaniasis (ADCL), which is the origin of considerable morbidity. Despite the outstanding advances in the characterization of the trypanosomatid genomes and proteomes, the biology of this species has been scarcely explored. However, the close relation of L. pifanoi to the sequenced species L. mexicana and others included in the “L. mexicana complex” allowed us to perform a two-dimension electrophoresis (2DE) approach to the promastigote proteome at the differential expression level. Protein identifications were performed by matrix-assisted laser desorption-ionization tandem time-of-flight mass spectrometry (MALDI-TOF/TOF). This insight has revealed similarities and differences between L. pifanoi and other species responsible for cutaneous and visceral leishmaniasis. Interestingly, certain proteins that were previously described as immunostimulatory (elongation factor 1β, trypanothione peroxidase, heat shock protein 70, enolase, GDP-forming succinyl-CoA and aldehyde dehydrogenase) are more abundant in the final growth stages of promastigotes (late-logarithmic and/or stationary phase) in the case of L. pifanoi., This work has been funded with project AGL2010-21806-C02-01 (Spanish Ministry of Economy and Competitiveness, formerly Spanish Ministry of Science and Innovation) and contract 050204100014, OTT code 20100338 (Ramón Areces Foundation).

A quantitative real-time PCR system (Q-PCR) for the detection and quantification of wheat DNA in food for celiacs has been developed and optimised. The DNA was extracted with a new procedure, based on the SDS/Guanidine–HCl/Proteinase K method, but faster, with a higher yield and enough purity to avoid an additional purification step. This is the first report that compares the information provided by a Q-PCR technique with the prolamin levels determined with the most frequently used commercially available ELISA, based on the R5 monoclonal antibody. With the exception of some hydrolysed and highly processed food samples (such as beers, syrups, malt extracts, breakfast cereals…), the rest of the food with prolamin levels above the R5 ELISA quantification limit (1.5 mg/kg) have given positive signals with the Q-PCR system. Moreover, some food samples with prolamin levels below 1.5 mg/kg have also given positive signals with the Q-PCR system, indicating a better sensitivity of the DNA technique. Therefore, the developed Q-PCR system can be used as a non-immunological tool in order to confirm, by the “DNA pathway”, the presence of wheat in food not only for celiacs but also for individuals with wheat allergy.

The gluten content in various glucose syrups was determined by two sandwich ELISA methods and one competitive ELISA. Different extraction solutions were used for ELISA methods. MALDI-TOF mass spectrometry and SDS-PAGE were also carried out as a complementary technique to ELISA methods. The analysis proved that glucose syrups analyzed in this work and used in many food products and gluten-free food products are safe for patients suffering from celiac disease. Four food products containing glucose syrup were analyzed with satisfactory results as well. One sample of chocolate bar has gluten content lower than the current limit for gluten-free foods. Gluten content above this limit was found in this chocolate bar after cocktail-gelatine extraction. This product is not labelled as gluten-free food. This fact shows that the analyses of gluten-free products are not simple and need more work and attention.