The Immunology Core will provide the immunological assays for all of the projects. These assays will result in data to be used along with health status data for staging and estimation of disease progression. The immunology data will provide the dependent variables for hypotheses related to immune function in the studies included in this program project. The selection of assays for this core was thus dictated by the questions put forward in the three studies. This core will produce the data set for the generalizability analyses to be conducted in the Biostatistical Core. This data set will be analyzed by the Biostatistical Core in order to determine, if possible, the contribution of gender and ethnicity to the variance in immunologic markers.