Effectiveness of donor natural killer cell alloreactivity in mismatched hematopoietic transplants

T cells that accompany allogeneic hematopoietic grafts for treating leukemia enhance engraftment and mediate the graft-versus-leukemia effect. Unfortunately, alloreactive T cells also cause graft-versus-host disease (GVHD). T cell depletion prevents GVHD but increases the risk of graft rejection and leukemic relapse. In human transplants, we show that donor-versus-recipient natural killer (NK)-cell alloreactivity could eliminate leukemia relapse and graft rejection and protect patients against GVHD. In mice, the pretransplant infusion of alloreactive NK cells obviated the need for high-intensity conditioning and reduced GVHD. NK cell alloreactivity may thus provide a powerful tool for enhancing the efficacy and safety of allogeneic hematopoietic transplantation.     

Lethal and sublethal responses of <Emphasis Type="Italic">Sitophilus zeamais</Emphasis> populations to essential oils

The present study aimed to assess the lethal and sublethal responses of five populations of S. zeamais to the essential oils of Ocimum basilicum and Piper hispidinervum, through toxicity, locomotor behavior (flight and walking activities) and physiological (respiration rate and body mass) evaluations. The populations of S. zeamais were obtained from Machado—MG, Paracatu—MG, Piracicaba—SP, Recife—PE and Tunápolis—SC. To estimate the LC₅₀ of each oil for each population, fumigation tests were performed. The population from Recife exhibited the lowest instantaneous rate of increase (ri) as well the lowest consumption of grain mass. However, Piracicaba was considered the susceptibility pattern, presenting the lowest LC₅₀ for both essential oils, no statistical difference was observed among populations or treatments in the flight activity bioassays. The essential oils effect on walking activity and respiration rates varied among populations. The population from Recife presented the highest walked distance and walk speed, with the lowest resting time and number of stops, as well as the lowest respiration rate and body mass. The present study highlights the importance of the study on population responses, as the five populations of S. zeamais exhibited different patterns of toxic and behavioral effects when subjected to the essential oils of P. hispidinervum and O. basilicum.