This proposal will explore flow cytometric analysis and cell sorting in a number of NIH funded grants and pilot projects that cannot be accommodated due to the inadequacies or the lack of available time on the extant EPICs 5 single laser flow cytometer and cell sorter in vitro. One aspect of this request involves the sequential monitoring of tumor cell and T immunoregulatory cell subset phenotype and function in human Non-Hodgkins lymphoma in the Balb C mouse. It will also allow expansion of studies in Mycosis Fungoides, a T cell lymphoproliferative malignancy. Where flow cytometric analysis of cell cycle events may predict which patients are at risk for relapse and/or progression to more aggressive stages of disease. Another aspect of this request is involved in performing similar sequential flow cytometric analysis of immunoregulatory T cell subset analysis in patients and in a monkey and rabbit model of hypersensitivity pneumonitis. This spectrum of environmentally caused inflammatory lung diseases is economically and occupationally important and may be caused by imbalances in immunoregulatory subset function and/or activation. The third and fourth aspect of this application involves performing similar sequential analysis in patients being treated with human lymphocyte interferon for CLL, a disease where immunoregulatory imbalances are known to correlate with disease activity to assess the effects of interferon on the tumor burden and immunoregulatory T cell subset phenotype and function and in the Acquired Immunodeficiency Syndrome in homosexuals and hemophiliacs. Many of these studies may afford important insights for diagnosis, prognosis, treatment and pathogenesis of a variety of human disease but all require state of the art flow cytometric and cell sorting equipment.