Association between Plasma Antibody Response and Protection in Rainbow Trout Oncorhynchus mykiss Immersion Vaccinated against Yersinia ruckeri

A key hallmark of the vertebrate adaptive immune system is the generation of antigen-specific antibodies from B cells. Fish are the most primitive gnathostomes (jawed vertebrates) possessing an adaptive immune system. Vaccination of rainbow trout against enteric redmouth disease (ERM) by immersion in Yersinia ruckeri bacterin confers a high degree of protection to the fish. The immune mechanisms responsible for protection may comprise both cellular and humoral elements but the role of specific immunoglobulins in this system has been questioned and not previously described. The present study demonstrates significant increase in plasma antibody titers following immersion vaccination and significantly reduced mortality during Y. ruckeri challenge

Evidence of an Antimicrobial-Immunomodulatory Role of Atlantic Salmon Cathelicidins during Infection with Yersinia ruckeri

Cathelicidins are a family of antimicrobial peptides that act as effector molecules of the innate immune system with broad-spectrum antimicrobial properties. These evolutionary conserved cationic host-defence peptides are integral components of the immune response of fish, which are generally believed to rely heavily on innate immune defences to invading pathogens. In this study we showed that Atlantic salmon cathelicidin 1 and 2 (asCATH1 and asCATH2) stimulated peripheral blood leukocytes increasing the transcription of the chemokine interleukin-8. Further, functional differences were identified between the two cathelicidins. In the presence of serum, asCATH1 displayed greatly diminished host haemolytic activity, while the constitutively expressed asCATH2 had no haemolytic activity with or without serum. These findings support our hypothesis that fish cathelicidins exert their primary antimicrobial action at the site of pathogen invasion such as epithelial surfaces. Further, we hypothesise that like their mammalian counterparts in the presence of serum they act as mediators of the innate and adaptive immune response via the release of cytokines thus indirectly protecting against a variety of pathogens. We highlight the importance of this immunomodulatory role from the involvement of asCATHs during an infection with the fish pathogen Yersinia ruckeri. While we were able to demonstrate in vitro that asCATH1 and 2, possessed direct microbicidal activity against the fish pathogen, Vibrio anguillarum, and a common gram negative bacterium, Escherichia coli, little or no bactericidal activity was found against Y. ruckeri. The contribution of either asCATH in the immune response or as a potential virulence factor during yersiniosis is highlighted from the increased expression of asCATH1 and 2 mRNA during an in vivo challenge with Y. ruckeri . We propose that Atlantic salmon cathelicidins participate in the interplay between the innate and adaptive immune systems via the release of cytokines enabling a more effective response to invading pathogens

Scientific Opinion on the safety of ferrous ammonium phosphate as a source of iron added for nutritional purposes to foods for the general population (including food supplements) and to foods for particular nutritional uses

The Panel on Food Additives and Nutrient Sources added to Food provides a scientific opinion on the safety of Ferrous Ammonium Phosphate (FAP) when added for nutritional purposes in foodstuffs for particular nutritional uses (PARNUTS) and foods intended for the general population (including food supplements) as a source of iron and on the bioavailability of iron from this source. FAP is stable at neutral pH in formulated foods. The bioavailability of iron from FAP was shown to be within the range of that from other iron salts used for fortification purposes, and specifically, less than that from ferrous sulphate and greater than that from ferric pyrophosphate. In intended food categories, FAP provides between 0.7 to 14 mg of iron per serving, which corresponds to 5 to 100% of the RDA for iron in adults. Studies evaluating the toxicity of FAP in experimental animals have not been conducted. FAP dissociates under the low pH conditions of the stomach in its components, thus releasing ferrous, ammonium and phosphate ions. Given the previous evaluations of ferrous, ammonium and phosphate salts as food additives and as nutrient sources by the SCF, EFSA and JECFA and that the available information on their toxicity did not identify toxicological effects, the Panel considers that additional toxicological data on FAP are not required. The Panel concludes that the use of FAP as a source of iron in PARNUTS and in foods intended for the general population (including food supplements), at the proposed use levels, is not of safety concern provided that established upper safety limits for iron are not exceeded

Scientific Opinion on the safety of Glycerol Esters of Tall Oil Rosin for the proposed uses as a food additive

The Panel on Food Additives and Nutrient Sources added to Food provides a scientific opinion evaluating the safety of glycerol esters of tall oil rosin (GETOR) for the proposed use as a stabilising and emulsifying food additive in certain beverages up to a maximum level of 100 mg/l. In view of the limited toxicity studies for GETOR, analytical data were submitted to demonstrate that GETOR are chemically equivalent to glycerol esters of wood rosin (GEWR) which have already been authorised as a food additive by Directive 95/2/EC. The Joint FAO/WHO Expert Committee on Food Additives decided that it could not evaluate GETOR without additional information on its composition, in order to clarify the extent and significance of any differences relative to other glycerol esters of rosins. GETOR are obtained by esterification of tall oil rosin and are described as a complex mixture of mono-, di- and tri-glycerol esters of resin acids (fraction (a)). Besides these esters, free resin acids (fraction (b)) and other saponifiable and unsaponifiable substances (fraction (c)) including sulphur compounds are present in GETOR. Conclusive analytical data on the proportions of fractions (a), (b), and (c) are not provided and also data on the identity and quantity of their individual components are absent. The results of two acute oral toxicity studies are the only toxicological data available for GETOR. Overall the Panel concluded that the chemical and toxicological characterisation of GETOR is not adequate. The Panel also could not conclude that GETOR is chemically equivalent to GEWR thus the toxicological data obtained with GEWR could not be used for read across. Therefore, the Panel concluded that the available data are too limited to conclude on the safety of GETOR as a food additive at the proposed uses and use level

Scientific Opinion on the re-evaluation of Amaranth (E 123) as a food additive

The Panel on Food Additives and Nutrient Sources added to Food provides a scientific opinion re-evaluating the safety of Amaranth (E 123). Amaranth has been previously evaluated by JECFA in 1972, 1975, 1978 and 1984, and the SCF in 1976, 1979 and 1983. In 1984 the SCF set an ADI for Amaranth of 0-0.8 mg/kg bw/day based on results from a 90-day rat study. In contrast, in 1984 JECFA allocated an ADI of 0-0.5 mg/kg bw/day Amaranth based on a long-term carcinogenicity study in rats. In evaluating the overall toxicological database on Amaranth, the Panel concludes that the point of departure for establishing an ADI for Amaranth can be defined as 15 mg/kg bw/day, taking both the results from the 2-year study and the reproductive and developmental toxicity studies into account. Therefore using an uncertainty factor of 100, the Panel establishes an ADI for Amaranth of 0.15 mg/kg bw/day. The Panel concludes that at the maximum permitted level of use and/or reported use levels of Amaranth (Tier 2), estimates of anticipated exposure for children (1-14 years old) are around 30 times lower than the ADI of 0.15 mg/kg bw/day at the high percentiles (95th/97.5th). However, for adults the anticipated exposure to Amaranth at the 97.5th percentile can be up to 6 times higher than the ADI. The Panel also notes that main contributors to total anticipated exposure to Amaranth for adults were from aperitif wine drinks and Americano. The Panel notes that anticipated exposure to these uses have been made with the maximum permitted levels of use for Americano although no usage value for this beverage was provided by industry, and with the maximum reported levels of use for aperitif wine drinks, which were reported by Industry to be at the same level as the maximum permitted level