Biomedical subjects
Publications and source records attributed to S D Rowley.
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Twenty patients with poor prognosis non-Hodgkin's lymphoma received regimens which employed cyclophosphamide and total body irradiation followed by autologous bone marrow rescue. There were two toxic deaths. All 10 patients with residual disease prior to treatment achieved a complete remission. Ten patients survive disease free from 1.4 to 9.5 years and median survival exceeds 2.9 years. The actuarial 3-year disease-free survival is 50%. Treatment with cyclophosphamide and total body irradiation followed by autologous bone marrow infusion is an effective salvage regimen for poor prognosis lymphoma. Durable long-term remissions can be achieved.
The investigation of human hematopoiesis is limited by the lack of an in vitro assay for the most primitive hematopoietic stem cell. In this report, we describe the culture from normal human bone marrow of unique colonies of morphologically immature cells with scanty, agranular, cytoplasm and a primitive nucleus with nucleoli. These "blast" cells demonstrate a significant ability for the generation of secondary colonies of multiple lineages, including additional blast cell colonies. These colonies are detected at various times during the culture period of up to 28 days. Neither the time of appearance in primary culture nor any feature of the morphological appearance of the blast cells is correlated with replating ability or the differentiation pathway followed. The progenitor cell giving rise to these colonies may represent the earliest pluripotent hematopoietic stem cell yet grown in culture.
Cells from three different human neuroblastoma cell lines and normal human bone marrow cells were exposed to the lipophilic fluorescent dye, merocyanine 540 (MC 540), and white light. In vitro clonogenic tumor cells were inactivated up to 25,000 times more rapidly than multipotent hematopoietic progenitor cells (CFU-GEMM). It is conceivable that this pronounced difference in sensitivity to MC 540-mediated photolysis can be exploited for the selective killing of residual neuroblastoma cells in autologous remission marrow grafts.
The My-10 glycoprotein is an hematopoietic cell surface antigen expressed specifically by undifferentiated (blast) cells, constituting 1%-4% of normal adult bone marrow leukocytes. We used several immunological and in vitro culture methods to analyze the expression of this unique antigen on a variety of lymphohematopoietic progenitor cells. Colony-forming cells (CFC) for granulocyte-monocyte colonies (CFC-GM) and erythroid colonies (BFU-E) were predominantly My-10 positive. CFC with higher proliferative potential were more strongly My-10 positive than CFC with lower proliferative potential, and those for mixed-lineage and blast cell colonies were even more uniformly My-10 positive. Cells maintaining CFC-GM number in short-term marrow culture (pre-CFC) were found to be My-10 positive, as were lymphoid precursors defined by their content of intranuclear terminal deoxynucleotidyl transferase. More mature erythroid precursors (CFU-E) were heterogeneous for antigen expression and lost My-10 antigen progressively, in parallel with advancing maturational stage. The My-10 antigen permits rapid identification and purification of hematopoietic progenitor cells for further study or potential clinical application. The disappearance of the My-10 antigen, moreover, may be a probe for differentiation-linked cellular events.
This institution has documented consistent reconstitution of hematopoiesis in patients treated with marrow lethal chemoradiotherapy who are "rescued" by reinfusion of autologous cryopreserved marrow cells incubated with 4-hydroperoxycyclophosphamide (4-HC) for in vitro purging of occult tumor cells. After 4-HC incubation, the reinfusion marrow cells showed marked reduction in committed progenitor cell (BFU-E, CFU-GM) frequency, and often total absence of detectable progenitors, without significant loss of marrow reconstituting ability. Since BFU-E and CFU-GM assays did not predict marrow reconstituting ability after 4-HC incubation, we sought to determine whether multilineage progenitor cells (CFU-GEMM) might be more resistant to 4-HC incubation and therefore a more reliable predictive assay in this setting. We found that BFU-E, CFU-GM, and CFU-GEMM all show similar dose-related sensitivity to in vitro incubation with 4-HC and do not appear representative of the cell(s) responsible for marrow reconstitution.
Perforation of the esophagus is potentially the most lethal of any site in the gastrointestinal tract and is also the greatest therapeutic challenge. Although uncommon, esophageal perforation continues to occur even in the hands of very well-trained and experienced endoscopists. The literature reports the incidence of instrumental esophageal perforation to be between 0.25% and 1%. A review of 374 consecutive rigid esophagoscopies at the Naval Regional Medical Center, Oakland, CA, over a three-year period revealed three perforations for an overall incidence of 0.8%. This paper will review cases.
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The replication of the Bacillus subtilis bacteriophages SPP-1 and phi 105 is sensitive to 6-(p-hydroxyphenylazo)-uracil (HPUra), a selective inhibitor of replicative DNA synthesis of B. subtilis which acts specifically at the levels of a replication-specific polymerase, DNA polymerase III (pol III). The origin of the HPUra-sensitive polymerase required for phage replication was examined by comparison of the drug sensitivity of phage development in a normosensitive host with that in a host carrying azp-12, a polC mutation that specifies production of an HPUra-resistant pol III. azp-12 specified HPUra-resistant phage host pol III. The host polIII requirement for SPP-1 replication also was confirmed by the demonstration that phage development was temperature sensitive in a host mutant carrying the polC mutation mut-1 (ts). Examination of the pol III activity of crude and purified cell-free preparations derived from phage-infected cells did not indicate any detectable changes in the specific activity, purification behavior, or drug sensitivity of the enzyme.
In a series of 100 bone marrow harvests, the incidence of bacterial contamination of the bone marrow graft was 17 percent. Ex vivo manipulation of some of the grafts prior to infusion may have caused additional bacterial contamination. All isolated bacteria were common skin flora, and no serious sequelae were observed in the patients receiving the culture-positive bone marrow grafts. Samples of harvested bone marrows purposely contaminated with an isolate of Staphylococcus epidermidis demonstrated a bactericidal property that was maximal early after bone marrow collection. Bone marrow collection and ex vivo manipulation may result in considerable bacterial contamination. Procedures must be developed to assure that marrow collection and processing do not result in clinically significant contamination.
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BACKGROUND: Apheresis devices designed for the collection of mature blood elements are being used for the collection of peripheral blood progenitor cells (PBPCs). The collection of PBPCs differs from that of other cells in the rarity of the target cell and in the fact that donors may undergo several days of collection. A consequence of this process may be a depletion of blood cells such as platelets from the blood. The disposable set and operating software for an apheresis device (Spectra, COBE BCT) was modified by the manufacturer to automate the collection of PBPCs and reduce the collection of unwanted blood cells. STUDY DESIGN AND METHODS: A study was initiated to compare the collection of PBPCs with the new device, the AutoPBSC (version [V]6.0 with AutoPBSC tubing set), and that with the MNC (mononuclear cell) procedure (V4.7 with white cell tubing set), for patients and healthy donors. RESULTS: Patients whose blood was processed by either theV6.0 orV4.7 procedure achieved the target dose of 5 x 10(6) CD34+ cells per kg of patient weight in similar numbers of procedures, even though the calculated collection efficiency for CD34+ cells using the automated V6.0 procedure was significantly less than that with the V4.7 procedure for both allogeneic donors and patients donating PBPCs. The collection efficiency for platelets was lower with the V6.0 procedure, and components collected in this manner contained fewer platelets. Apheresis by the V6.0 procedure required 30 to 60 more minutes per procedure than apheresis by the V4.7 procedure. Review of engraftment kinetics after transplantation did not reveal any effect of the collection procedure on recipients of either allogeneic or autologous transplants. CONCLUSION: The collection efficiencies of the V6.0 procedure for both CD34+ cells and mature blood cells are lower than those of the V4.7 procedure. The lower collection efficiency for platelets results in a smaller drop in peripheral blood platelet count after the procedure. The automated features of the V6.0 procedure may simplify PBPC collection, but this procedure requires a longer apheresis.