The creation of an improved vaccine for global measles control will require an understanding of the immune mechanisms of measles virus containment. To assess the role of CD8 ؉ cytotoxic T lymphocytes in measles virus clearance, rhesus monkeys were depleted of CD8؉ lymphocytes by monoclonal anti-CD8 antibody infusion and challenged with wild-type measles virus. The CD8 ؉ lymphocyte-depleted animals exhibited a more extensive rash, higher viral loads at the peak of virus replication, and a longer duration of viremia than did the control antibody-treated animals. These findings indicate a central role for CD8؉ lymphocytes in the control of measles virus infections and the importance of eliciting a cell-mediated immune response in new measles vaccine strategies.Measles remains an important cause of morbidity and mortality in young children. Although a preventative live attenuated measles virus (MV) vaccine has long been available, its efficacy is incomplete. The immunogenicity of this vaccine has been limited in young infants by maternal antibody interference and immune system immaturity (6), leaving substantial numbers of vaccinated infants susceptible to disease. In fact, approximately 1 million deaths per year are still attributable to measles, with the majority of these deaths occurring in subSaharan Africa (1).Defining the immune mechanisms critical for the control of MV replication will be important in developing new measles vaccination strategies. It is well established that anti-MV antibodies play a central role in protection against MV infection. However, accruing data have implicated cell-mediated immune responses in the control of MV replication (10,16,17,23,34). MV-specific, CD8 ϩ cytotoxic T lymphocytes are known to be activated and expanded in the peripheral blood in temporal association with the onset of the measles rash (16,17,21,30). Soluble CD8 and ␤ 2 microglobulin are increased in the plasma during acute measles infection in children (12).A number of clinical observations have also implicated MVspecific cellular immune responses in the clearance of this virus. Children with cellular immune deficiencies have more severe clinical disease after MV infection than children who are hypogammaglobulinemic or who are immunologically intact (8,24), and the potency of the cell-mediated immune response has been correlated with the ability of infected individuals to recover from MV infection (3). Human immunodeficiency virus-infected children are more likely to have prolonged shedding of MV than those who are human immunodeficiency virus negative (26), presumably because of impaired MV-specific cellular immune responses. In a transgenic mouse model of MV infection (25), the T-lymphocytemediated immune response is required for clearance of neuronal infection (22). Nevertheless, these observations have all been correlative. The importance of cell-mediated immunity in MV clearance has not been directly demonstrated.Nonhuman primates can be infected with MV experimentally and provide the only available animal mod...

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ÃÃThe Korea Atomic Energy Research Institute (KAERI) has been developing the Direct Use of Spent Pressurized Water Reactor (PWR) Fuel in the CANada Deuterium Uranium (CANDU) Reactors (DUPIC) fuel fabrication technology since 1992, and the basic DUPIC fuel fabrication process was established in 2002. In order to demonstrate the robustness of the DUPIC fuel fabrication process through the irradiation test, it is important that a Quality Assurance (QA) program should be in place before a fabrication of the DUPIC fuel. Therefore, the Quality Assurance Manual (QM) for the DUPIC fuel was developed on the basis of the Canadian standard, CAN3-Z299.2-85. This manual describes the quality management system applicable to the activities performed for the DUPIC fuel fabrication at KAERI. In order to demonstrate the DUPIC fuel fabrication technology and produce qualified DUPIC fuel pellets, the process qualification tests were performed, which include three pre-qualification tests and three qualification tests. The characteristics of the DUPIC fuel pellets such as the sintered density, grain size, and surface roughness were measured and evaluated in accordance with the QA procedures. The optimum fabrication process of the DUPIC fuel pellet was also established based on the qualification results. Finally a production campaign was carried out to fabricate the DUPIC fuel pellets at a batch size of 1 kg following the QA program. As a result of the production campaign, qualified DUPIC fuel pellets were successfully produced and, therefore, the remote fuel fabrication technology of the DUPIC fuel pellet was demonstrated.