Interleukin 7 from Maternal Milk Crosses the Intestinal Barrier and Modulates T- Cell Development in Offspring

Background Breastfeeding protects against illnesses and death in hazardous environments, an effect partly mediated by improved immune function. One hypothesis suggests that factors within milk supplement the inadequate immune response of the offspring, but this has not been able to account for a series of observations showing that factors within maternally derived milk may supplement the development of the immune system through a direct effect on the primary lymphoid organs. In a previous human study we reported evidence suggesting a link between IL-7 in breast milk and the thymic output of infants. Here we report evidence in mice of direct action of maternally-derived IL-7 on T cell development in the offspring. Methods and Findings  We have used recombinant IL-7 labelled with a fluorescent dye to trace the movement in live mice of IL-7 from the stomach across the gut and into the lymphoid tissues. To validate the functional ability of maternally derived IL- 7 we cross fostered IL-7 knock-out mice onto normal wild type mothers. Subsets of thymocytes and populations of peripheral T cells were significantly higher than those found in knock-out mice receiving milk from IL-7 knock-out mothers. Conclusions/Significance Our study provides direct evidence that interleukin 7, a factor which is critical in the development of T lymphocytes, when maternally derived can transfer across the intestine of the offspring, increase T cell production in the thymus and support the survival of T cells in the peripheral secondary lymphoid tissue

A qualitative evaluation of a novel intervention using insight into tobacco industry tactics to prevent the uptake of smoking in school-aged children

Background: Evidence from the US Truth campaign suggests that interventions focusing on tobacco industry tactics can be effective in preventing smoking uptake by children. Operation Smoke Storm is the first school-based intervention based on this premise and comprises three classroom sessions in which students act as secret agents uncovering tobacco industry tactics through videos, quizzes, discussions, and presentations. We report a qualitative evaluation of its acceptability. Methods: We conducted eight focus groups with 79 students aged 11-12 who participated in Operation Smoke Storm at two UK schools in Autumn 2013, and 20 interviews with teachers who delivered the intervention. These were digitally audio-recorded, transcribed verbatim and analysed using the framework method. Results: Students enjoyed the secret agent scenario and reported acquiring new knowledge about smoking and the tobacco industry, which seemed to strengthen their aversion to smoking. Teachers felt confident delivering the ‘off the shelf’ resource, although they would have welcomed more background information about the topic and guidance on steering discussions. Teachers highlighted a need for the resource to be flexible and not dependent on lesson length, teacher confidence, or expertise. Students and teachers endorsed the idea of developing a booster component for older students and supported the development of printed information complementing the resource to encourage parents to support their child not to smoke. Conclusions: These findings demonstrate that Operation Smoke Storm can be delivered by teachers to raise awareness about smoking-related issues. The ideas and issues raised are now being used to improve and extend the resource for further evaluation

Controlling water deficit by osmolytes and enzymes: Enhancement of carbohydrate mobilization to overcome osmotic stress in wheat subjected to water deficit conditions

The present study demonstrates the effect of polyethylene glycol-6000 (PEG) induced water-deficit stress on growth, physiological and biochemical responses in six wheat (Triticum aestivum L.) cultivars viz. C 306, C 273, PBW 175 (drought tolerant), PBW 534, PBW 343 and PBW 550 (drought susceptibile) at seedling stage for six days. Stress caused short stature in shoot and elongated roots in all cultivars. Significant reduction in chlorophyll content and increase in membrane injury index and lipid peroxide content were observed in all the cultivars. Water stress accentuated sucrose synthase/phosphate synthase activities while sucrolytic enzymes namely; acid, neutral and sucrose synthase (cleavage) got repressed. Higher build up of sucrose and lower activity of amylase in root and shoot further decreased reducing sugar (glucose, fructose) content in stressed seedlings. Though the sugar supply (sucrose) under stress was not a limiting factor for germination but the poorer ‘metabolic conversion efficiency’ via sucrolytic enzymes in root and shoot resulted in their favoured utilization in amino acid, proline and glycine betaine. It may therefore be concluded that certain traits namely: membrane stability parameters, sugars, enzymes and osmolytes might help the cultivars to tolerate water deficit conditions.Keywords: Carbohydrates, chlorophyll, sucrose metabolism, membrane stability parameters, proline, protein, starch, Triticum aestivum, water-deficit.African Journal of Biotechnology, Vol 13(19), 2072-208

Modulation of proline metabolism under drought and salt stress conditions in wheat seedlings

114-124Drought and salinity are the major environmental constraints that limit plant growth and productivity. In the present investigation, shoots of seven day old plantlets of nineteen wheat genotypes (PBW621, PBW660, PBW175, HD3086, WH1105, HD2967, C306, C273, C518, C591, Type 11, Excalibar, Gladius, Drysdale, Babax, Krichauff, Kharchia, Krl 1-4 and Krl 19) were evaluated for proline metabolism and its cross-talk with various biochemical parameters under water deficit, water withholding and salinity stress conditions. Principle component analysis categorized the genotypes into four groups: i.e. drought tolerant (Excalibar, Krichauff, Babax, Drysdale, Gladius and C306), salt tolerant (Kharchia, Type11, Krl1-4 and Krl19), low stress tolerant (C273, C518 and C591) and susceptible (HD2967, PBW621, WH1105, HD3086, PBW660 and PBW175). Tolerant genotypes possessed increased proline content and 1,1 diphenyl-picryl hydrazyl (DPPH) radical scavenging activity along with the reduced magnitude of thiobarbituric acid reactive species in parallel with decreased H2O2 content. Proline accumulation in shoots of tolerant genotypes under stress conditions may be an adaptative strategy, as it supplies energy for growth and lowers the generation of free radicals and reduces the lipid peroxidation linked membrane damage resulting in their stabilization. Glutamate dehydrogenase might have played a dominant role in ammonium assimilation and glutamate biosynthesis, leading to an increased glutamate pool, which via pyrroline-5-carboxylate synthetase activity led to enhanced proline accumulation in tolerant genotypes under stress conditions. Water withholding condition induced the stimulation of proline synthesis via increased glutamate dehydrogenase (GDH), pyrroline-5-carboxylate synthetase (P5CS) and pyrroline-5-carboxylate reductase (P5CR) activities with inhibition of oxidation via reduced proline dehydrogenase activity to a large extent as compared to water deficit and salt stress conditions. Our results highlight that in certain genotypes, GDH under water deficit, P5CS and PDH under salt stress and P5CR under water withholding stress condition were responsible for stress tolerance and could be used as a selectable marker

Heat and drought stress responses alter grain characteristics by impeding starch precursors of wheat

565-572In semi-tropical regions, particularly in Punjab (India), drought and high temperature stress are serious constraints for wheat production. Understanding the key metabolic steps may help the breeders and biotechnologist to develop heat and drought tolerant genotypes. Six wheat cultivars, namely PBW 343, PBW 550, PBW 621, PBW 175, C 306 and HD 2967 were extensively characterized for transformation of sugars to starch under heat and drought stress conditions. Significant reduction in enzyme activities of ADP-Glucose pyrophosphorylase (AGPase), alkaline inorganic pyrophosphatase and phosphofructokinase (PFK) in conjunction with reduced starch content under heat and drought stress conditions was apparent. However, contents of reducing sugars and fructans were increased while amylose and amylopectin content decreased. Correlation analysis revealed positive correlation of amylose with alkaline inorganic pyrophosphatase and starch with AGPase and PFK. Role of PFK was evident from correlation between AGPase and PFK indicating its predominant role in providing substrate for AGPase activity. Significant effects of stress treatments (T), genotype (G) and genotype-by-treatment (G×T) interaction were observed for AGPase, alkaline inorganic pyrophosphatase and PFK, amylose, amylopectin, starch, total sugars, fructans, 1000 grain weight and plant height. Thousand grain weights decreased more under heat stress as compared to drought stress indicating higher severity of the former stress