Frederic I. Preffer, PhD
Massachusetts General Hospital
Associate Professor of Pathology
Harvard Medical School
"Elucidating the immunophenotype and functional capacity of stem cells capable of developing into various tissue lineages..." A stem cell has the unique capacity to both self-renew and to give rise to specialized cells. Until recently it was believed that only embryonic stem cells were pluripotent and only they could give rise to committed cells of various diff erent tissues with diff erent function.
Over the past few years, it has become apparent that stem cells derived from differentiated adult tissue may also develop into mature cell types of disparate tissue. Hematopoietic stem cells are characteristically quiescent, multipotent cells with both the capacity for self-renewal and differentiation. After development in the fetus, these cells reside in adult bone marrow and serve to replenish lymphoid, megakaryocytic, erythroid and myeloid hematopoietic lineages throughout the lifetime of the host. Early investigations in this laboratory discerned that cells obtained from adult blood within a CD3-7+ lymphocyte compartment could develop predominantly in vitro into mature gamma delta+ T cells. Later studies fi ne-tuned this compartment into CD7+/CD7- and CD16+/ CD16- divisions.
Of particular present interest are side populations [SP] cells, which are relatively rare cells found in both the circulation and bone marrow. These CD34 negative cells, when isolated from human blood, have been shown to be capable of developing into T, NK and possibly dendritic cells. Recently, 'cancer stem cells' have been a topic of study and these have been identified in murine models of ovarian cancer and from cells obtained from individuals with this disease.
Other interests in the research laboratory involve the study of patients administered HLA mismatched transplants, done in collaboration with the Transplantation Biology Research Center and Bone Marrow Transplantation Units. The goal of these studies is to establish a state of mixed chimerism in patients with hematologic malignancies, so as to provide a minimum of 'graft vs. host' and a maximum of 'graft vs. leukemia' effects.
The MGH/Boston research flow cytometry laboratory is located on Simches 3.434. This is a valuable hospital core resource, and will entertain research collaborations from throughout the university. The laboratory contains a state of- the-art 5-laser DiVa cell sorter and 7-laser LSR-2. The cell sorter has 11 photomultiplier tubes and is capable of 4-way high speed cell sorting. The numerous laser excitation lines and photomultiplier capacity provides a wide breadth of capability to both instruments, which are superbly operated by Mr. David Dombkowski. A new research laboratory has been recently opened on CNY6.307. This laboratory contains a SORP – FACSAria II and SORP - LSRII. The clinical flow cytometry laboratory is located on Warren 5 on the MGH campus in Boston. Four- and eight-color analytic instrumentation [FACSCalibur, FACSCanto-II] are available at that site.
Frederic I. Preffer, PhD