Preapheresis peripheral blood CD34+ mononuclear cell counts as predictors of progenitor cell yield.

Background: Peripheral blood progenitor cells, harvested by apheresis after mobilization, provide rapid hematologic recovery after high-dose chemotherapy. However, because harvesting these cells is expensive and time-consuming, there has been much interest in optimizing collection protocols. An investigation was made to determine whether, in this clinical setting, peripheral blood progenitor cell yields may be predicted from preapheresis progenitor cell counts, allowing the length of each procedure to be "fine tuned" to achieve specific target goals.

Complete blockade of B7 family-mediated costimulation is necessary to induce human alloantigen-specific anergy: a method to ameliorate graft-versus-host disease and extend the donor pool.

Graft-versus-host disease (GVHD) is initiated by adoptively transferred donor T cells that recognize host alloantigens. Whereas the absence of donor T-cell proliferation to host alloantigens in a mixed-leukocyte reaction does not predict freedom from GVHD, the frequency of alloreactive precursor helper T lymphocytes (pHTL) is predictive. Complete blockade of 87 family-mediated costimulation, but not of major histocompatibility complex recognition or adhesion, induces host alloantigenic-specific energy by reducing cytokine production below threshold levels necessary for common gamma chain signaling.

The collection and evaluation of peripheral blood progenitor cells sufficient for repetitive cycles of high-dose chemotherapy support.

Background: The development of an optimized peripheral blood progenitor cell (PBPC) harvest protocol to provide support for repetitive chemotherapy cycles is described.

Study Design And Methods: PBPCs mobilized by cyclophosphamide plus granulocyte-colony-stimulating factor (G-CSF) were studied in 163 leukapheresis harvests from 26 lymphoma patients. Harvested cells were transfused with two chemotherapy cycles and with an autologous bone marrow transplant.