Ontogenic Development of Th1 and Th2 Cytokine Capabilities in Random Bred Mice

Neonatal mouse Th1 capabilities mature by postnatal day 5. Neonatal T cells have been reported to exhibit a bias towards Th2 cytokine production when co-cultured with adult antigen presenting cells (APC). We studied mouse T cells co-cultured with contemporary APC to evaluate neonatal cytokine production capabilities. In response to allogeneic stimulation, T cells co-cultured with contemporary APC from day 5 pups produced 37-fold greater IFNγ and 1.4-fold greater IL-2 levels than day 20 weanling mice. After CD3 ligation, cells from day 5 pups produced 4- (IL-2) and 10-fold (IFNγ) greater levels than adults (day 45), and concentrations were 27- (IL-2) and 18-fold (IFNγ) higher than with allogeneic stimulation alone. On average, the percent difference in concentrations was 418 (IL-4), 286 (IL-2) and 1140% (IFNγ) higher in unseparated spleen cells than in isolated splenic CD4 cells and APC. These results demonstrate that, in response to allogeneic stimulation with or without CD3 ligation, lymphocytes of neonatal mice (day 5) have the capacity to produce equivalent or greater TcR-dependent Th1 cytokine (IL-2 and IFNγ) levels than adult mice. Findings also support the idea that the reported Th2 bias of neonatal T cells may be the result of in vitro manipulation and choice of mouse strain, not of an inherent bias

Maternal Modulation of Neonatal Immune System Development

Changes in programming of neonatal immune development were effected through maternal immune modulation (Leishmania major inoculation). In progeny of these dams, immune profiles in both blood and spleen were changed throughout the neonatal period and were pronounced after weaning. White blood cell (WBC) and lymphocyte counts in blood of 45-day-old progeny were two-fold less than control animals. In blood, proportions of B cells were greater, while T helpers, Tc/s and NK cells were less than in controls. In contrast, proportions of splenic B and NK cells were greater than controls. But, proportions of all T and Tc/s cells on d20 and 45 were lower than controls. In blood, absolute numbers of all T, Th naïve and Th memory cells were lower than in controls. In contrast, in the spleen, numbers of NK, T and Th naïve and memory cells were up to 200% greater than in control pups. Cytokine responses of splenic lymphocytes stimulated through CD3 ligation revealed no difference in IL-4 production. In contrast, IL-2 and IFNγ were lower on d45 and 5, respectively, in the experimental compared to control mice. These data support the hypothesis that maternal immune events during gestation can modulate the pattern of immune development in offspring

Maturation of Lymphocyte Immunophenotypes and Memory T Helper Cell Differentiation During Development in Mice

The goal of this study was to systematically investigate the ontogeny of lymphoid populations throughout postnatal development. In CD-1 mice, peak lymphocyte numbers occurred in blood on postnatal day 10 (dl0) including those for natural killers (NK1.1), B cells (CD19), T helper (CD3CD4), naïve T helper (CD4CD62L(pos)CD44(low)), memory T helper (CD4CD62L(neg)CD44(high)), and T cytotoxic (CD3CD8) cells. As percent of total lymphocytes, peaks were achieved by d10 for all T helper subtypes but not B cells which declined to a nadir. In spleen, lymphocyte numbers increased exponentially after d10. Proportionately, NK and T cells peaked on d10, declined by d20, and increased 2–3-fold by d45. Naive T cells constituted the majority of lymphocytes during development while memory cells gained to 2.2% (blood) and 12 % (spleen) by d20. C57BL/6 mice had similar profiles except that the B cell nadir and T cell subset peaks were at d5. Peripheralization of critical numbers of lymphocytes by d10, and importantly, development of a repertoire of memory cells by d20, may define immune response capabilities that close the period of immaturity for the neonate

Challenge of Xenotransplantation in Pediatric Heart Transplantation

Although surgical techniques have progressively improved in the field of congenital heart disease (CHD), even such as hypoplastic left heart syndrome, pediatric heart transplantation is the most effective surgical option for complex CHD and cardiomyopathy with severe heart failure. However, even now, donor heart availability has been poor in children. Although technologies for ventricular assist device (VAD) have been progressing even in children, VAD cannot grow as the pediatric recipient grows. Therefore, pediatric cardiac xenotransplantation has a great possibility to save and grow children with end-stage heart failure. In this chapter, I would like to introduce the first pediatric baboon-to-human heart transplantation and its basic animal experiments done by Bailey’s group and the following attempts for pediatric cardiac orthotopic xenotransplantation (rhesus monkey-to-baboon and pig-to-primate combination)

Validation of Procedures for Monitoring Crewmember Immune Function - Short Duration Biological Investigation

Validation of Procedures for Monitoring Crew Member Immune Function - Short Duration Biological Investigation (Integrated Immune-SDBI) will assess the clinical risks resulting from the adverse effects of space flight on the human immune system and will validate a flightcompatible immune monitoring strategy. Immune system changes will be monitored by collecting and analyzing blood, urine and saliva samples from crewmembers before, during and after space flight

Exercise and functional foods

Appropriate nutrition is an essential prerequisite for effective improvement of athletic performance, conditioning, recovery from fatigue after exercise, and avoidance of injury. Nutritional supplements containing carbohydrates, proteins, vitamins, and minerals have been widely used in various sporting fields to provide a boost to the recommended daily allowance. In addition, several natural food components have been found to show physiological effects, and some of them are considered to be useful for promoting exercise performance or for prevention of injury. However, these foods should only be used when there is clear scientific evidence and with understanding of the physiological changes caused by exercise. This article describes various "functional foods" that have been reported to be effective for improving exercise performance or health promotion, along with the relevant physiological changes that occur during exercise