Selective expression of CD45 isoforms on functional subpopulations of CD34+ hemopoietic cells from human bone marrow.

We have found that the small population of cells in human marrow that are characterized by their expression of CD34 can be readily subdivided into two apparently nonoverlapping subpopulations of approximate equal size, one expressing CD45RO and one CD45R. Functional studies of these subpopulations revealed that all of the primitive erythroid colony-forming cells (BFU-E) are CD34+ CD45RO+. Similarly, more primitive cells that give rise to both erythroid and granulopoietic colony-forming cells after being maintained for 5 wk on confluent irradiated long-term marrow culture feeder layers, also show this phenotype. In contrast, most granulopoietic colony-forming cells are CD34+ CD45RO- cells. The differential expression of CD45 isoforms on distinct functional subpopulations of hemopoietic cells is consistent with the concept that these molecules play an important role in the differentiation or activation of primitive, normally quiescent, hemopoietic cells. The presence of CD45RO and the lack of CD45R on human cells capable of initiating hemopoiesis in the long-term marrow culture system correspond to the reported lack of CD45R on transplantable hemopoietic stem cells in rodents and may be a useful addition to strategies for human stem cell purification, or for purging CD45R+ leukemic cells.

Retroviral gene transfer to primitive normal and leukemic hematopoietic cells using clinically applicable procedures.

Clinical uses of gene transfer to bone marrow transplants require the establishment of a reproducible method for infecting large numbers of very primitive hematopoietic cells at high efficiency using cell-free retrovirus-containing media. In this study we report the results of experiments with preparations of a high-titer (2-5 x 10(7)/ml) helper-free recombinant neo(r) retrovirus that indicate this goal can now be achieved based on measurements of gene transfer efficiencies to cells referred to as long-term culture initiating cells (LTC-IC) because they give rise to clonogenic cells after greater than or equal to 5 wk in long-term culture (LTC). Intermittent, repeated exposure of normal human marrow mononuclear cells to virus-containing supernatant over a 3-d period of cell maintenance on an IL-3/granulocyte colony-stimulating factor (G-CSF) producing stromal layer resulted in gene transfer efficiencies to LTC-IC of 41%; a level previously obtainable only using co-cultivation infection techniques. Marrow cells enriched greater than or equal to 500-fold for LTC-IC (1-2% pure) by flow cytometry showed gene transfer efficiencies of 27% when infected in a similar fashion over a shorter period (24 h), but in the presence of added soluble IL-3 and G-CSF without stromal feeders, and this increased to 61% when Steel factor was also present during the infection period. By using a less highly enriched population of LTC-IC obtained by a bulk immunoselection technique applicable to large-scale clinical marrow harvests, gene transfer efficiencies to LTC-IC of 40% were achieved and this was increased to 60% by short-term preselection in G418. Southern analysis of DNA from the nonadherent cells produced by these LTC over a 6-wk period provided evidence of clonal evolution of LTC-IC in vitro. Leukemic chronic myelogenous leukemia LTC-IC were also infected at high efficiency using the same supernatant infection strategy with growth factor supplementation. These data demonstrate the feasibility of using cell-free virus preparations for infecting clinical marrow samples suitable for transplantation, as well as for further analysis of human marrow stem cell dynamics in vitro.

Leukocyte count as a predictor of death during remission induction in acute myeloid leukemia.

Acute myeloid leukemia (AML) presenting with a high leukocyte count has been associated with an increase in induction mortality and poor results in a number of other survival measures. However, the level at which an elevated leukocyte count has prognostic significance in AML remains unclear. In this report on a series of 375 adult (non-M3) AML patients undergoing induction chemotherapy at a single institution, leukocyte count analyzed as a continuous variable is shown to be a better predictor of induction death (ID) and overall survival (OS) than a leukocyte count of > or = 100 x 10(9)/L, a value characteristically associated with "hyperleukocytosis" (HL). In this patient cohort, a presenting leukocyte count of > or = 30 x 10(9)/L had high sensitivity and specificity for predicting ID, and both performance status (PS) and leukocyte count more accurately predicted for ID than age. Considering these parameters in newly-diagnosed AML patients may facilitate the development of strategies for reducing induction mortality.

Myeloablative allografting for chronic lymphocytic leukemia: evidence for a potent graft-versus-leukemia effect associated with graft-versus-host disease.

In all, 30 patients with CLL proceeded to myeloablative allogeneic BMT using related (n=20, 67%) or unrelated (n=10) donors, at the Princess Margaret Hospital (Toronto) (n=20) or the Leukemia/BMT Program of BC (Vancouver) (n=10), from 1989 to 2001. Median (range) interval from diagnosis to BMT was 4.8 (0.3-13) years, median number of prior therapies was three and median age 48 years. The preparative regimen included total body irradiation in 15 (50%). In all, 14 of 30 patients (47%) are alive, with median (range) follow up of 4.3 (2.4-10.5) years. All are in complete remission, two following therapy for post-BMT progression. Actuarial overall (OS) and event-free survival (EFS) at 5 years is 39% (OS 48% for related donor and 20% for unrelated donor BMT); cumulative incidence of nonrelapse mortality (NRM) and relapse is 47 and 19%, respectively. Both acute (RR=0.008, P=0.01) and chronic (RR=0.006, P=0.02) Graft-versus-host disease (GVHD) were associated with markedly decreased risk of relapse. Patients receiving grafts from unrelated donors had increased NRM (RR=3.6, P=0.02) and decreased OS (RR of death=3.4, P=0.002). Allogeneic BMT has resulted in long-term EFS in approximately 40% of patients with CLL. There is evidence for a strong graft-versus-leukemia effect associated with acute and chronic GVHD, resulting in near complete protection from relapse.

Growth factor regulation of the maintenance and differentiation of human long-term culture-initiating cells (LTC-IC).

Current evidence suggests that the most primitive of hematopoietic progenitors detectable in adult human marrow are cells that can give rise to clonogenic cells for > 5 weeks in vitro when co-cultured with certain stromal cells. Procedures developed to isolate these so-called long-term culture-initiating cells (LTC-IC) in highly purified form allow their separation from most other hematopoietic cells as well as from stromal cells and their precursors also present in the marrow. We have used such procedures in conjunction with the LTC system to identify specific growth factors that support human LTC-IC maintenance and differentiation and to make comparisons with effects on later events in hematopoiesis. In some studies, soluble growth factors were added exogenously to the study cultures. In others, marrow-derived fibroblasts were genetically engineered to allow increased levels of specific human growth factors to be endogenously produced. In both of these ways, the influence of granulocyte--macrophage colony-stimulating factor (GM-CSF), G-CSF, Interleukin-3 (IL-3), IL-6, and Steel factor were investigated. Increased provision of GM-CSF alone (or in combination with other factors) enhanced terminal cell differentiation (production of granulocytes and macrophages), although the same conditions had no influence on LTC-IC differentiation (production of clonogenic cells) or on LTC-IC maintenance. In contrast, G-CSF, IL-3 and IL-6 alone (and more so when combined) in the presence of feeders effectively enhanced LTC-IC differentiation and was less active on later stages of granulopoiesis. Provision of additional exogenous Steel factor also enhanced LTC-IC differentiation, although Steel factor alone, without feeders or other growth factors, did not support either the initial differentiation of LTC-IC into clonogenic cells or their subsequent differentiation into mature granulocytes and macrophages. No combination of exogenously added growth factors was found that enhanced LTC-IC maintenance over that achieved with primary marrow feeders. However, some murine fibroblasts (including those of SI/SI origin), as well as certain exogenous growth factors (including Steel factor), were able to substitute for feeders in this regard. These observations highlight the likelihood of redundancy in factors that can elicit similar biological responses at the earliest as well as later stages of hematopoietic cell development. Nevertheless, it appears that the responses of hematopoietic cells at different stages of differentiation to any particular factor may differ markedly and that the nature of any particular response is not yet predictable from a knowledge of effects on earlier or later cell types.

Telomerase is limiting the growth of acute myeloid leukemia cells.

Telomeres play an important role in the proliferation and senescence of normal and malignant cells. To test the role of telomerase in acute myeloid leukemia (AML), we expressed the telomerase reverse transcriptase (hTERT) gene, a dominant-negative hTERT (DN-hTERT) (D868A, D869A) gene, or a gene encoding green fluorescence protein (GFP) in the leukemia cell line K562 and in primary AML cells from different patients, using retroviral vectors. Cells transduced with hTERT exhibited elevated levels of telomerase activity compared to GFP controls, whereas cells expressing DN-hTERT had decreased telomerase activity. K562 populations transduced with DN-hTERT showed reduced clonogenicity, telomere dysfunction and increased numbers of apoptotic cells compared to GFP- or hTERT-transduced cells. Two of four clones transduced with DN-hTERT died after 30 and 53 population doublings, respectively. Transduced AML cells were tested in primary colony-forming unit (CFU) and suspension culture assays. Relative to hTERT- and GFP-transduced controls, AML cells transfected with DN-hTERT produced fewer CFU and showed lower engraftment after transplantation into sublethally irradiated beta(2)-m(-/-) nonobese diabetic/severe combined immunodeficient mice. We conclude that telomerase is limiting the growth of the leukemic cell line K562 and primary AML progenitor cells. Our data warrant further studies of the therapeutic use of telomerase inhibitors in AML.

Expression of HOX genes, HOX cofactors, and MLL in phenotypically and functionally defined subpopulations of leukemic and normal human hematopoietic cells.

To explore the possibility that deregulated HOX gene expression might commonly occur during leukemic hematopoiesis, we compared the relative levels of expression of these and related genes in phenotypically and functionally defined subpopulations of AML blasts and normal hematopoietic cells. Initially, a semi-quantitative RT-PCR technique was used to amplify total cDNA from total leukemic blast cell populations from 20 AML patients and light density cells from four normal bone marrows. Expression of HOX genes (A9, A10, B3 and B4), MEIS1 and MLL was easily detected in the majority of AML samples with the exception of two samples from patients with AML subtype M3 (which expressed only MLL). Low levels of HOXA9 and A10 but not B3 or B4 were seen in normal marrow while MLL was easily detected. PBX1a was difficult to detect in any AML sample but was seen in three of four normal marrows. Cells from nine AML patients and five normal bone marrows were FACS-sorted into CD34+CD38-, CD34+CD38+ and CD34-subpopulations, analyzed for their functional properties in long-term culture (LTC) and colony assays, and for gene expression using RT-PCR. 93 +/- 14% of AML LTC-initiating cells, 92 +/- 14% AML colony-forming cells, and >99% of normal LTC-IC and CFC were CD34+. The relative level of expression of the four HOX genes in amplified cDNA from CD34- as compared to CD34+CD38- normal cells was reduced >10-fold. However, in AML samples this down-regulation in HOX expression in CD34- as compared to CD34+CD38- cells was not seen (P < 0.05 for comparison between AML and normal). A similar difference between normal and AML subpopulations was seen when the relative levels of expression of MEIS1, and to a lesser extent MLL, were compared in CD34+ and CD34- cells (P < 0.05). In contrast, while some evidence of down-regulation of PBX1a was found in comparing CD34- to CD34+ normal cells it was difficult to detect expression of this gene in any subpopulation from most AML samples. Thus, the down-regulation of HOX, MEIS1 and to some extent MLL which occurs with normal hematopoietic differentiation is not seen in AML cells with similar functional and phenotypic properties.

Primitive acute myeloid leukemia cells with long-term proliferative ability in vitro and in vivo lack surface expression of c-kit (CD117).

A hierarchy of progenitor cells is thought to exist in human acute myeloid leukemia (AML), with only the most primitive cells capable of proliferating to maintain the malignant clone. To further characterize this AML cell hierarchy, we evaluated the coexpression of CD34 and c-kit (CD117) on cells that are capable of long-term proliferation in vitro and in vivo.AML cells were sorted for coexpression of CD34 and c-kit (CD117) using two c-kit monoclonal antibodies (mAbs), clones 95C3 and 104D2. Sorted subfractions were evaluated for the ability to produce colony-forming units (CFU) for up to 8 weeks in suspension culture (SC) and for the capacity to repopulate NOD/SCID mice. When expression of c-kit on blood cells from 19 AML patients at diagnosis was compared using both mAbs, expression defined by 104D2 (34% +/- 6% c-kit(+)) was somewhat higher than that defined using 95C3 (18% +/- 4%). AML cells were sorted for coexpression of CD34 and c-kit using both c-kit mAbs, and the subfractions were assayed in vitro and in vivo. Whereas the majority of AML blast cells lacked expression of CD34, most AML cells capable of proliferating to produce CFU after 4 to 8 weeks in SC were CD34(+)/c-kit(-). Cultures of sorted CD34(+)/c-kit(-) cells, supplemented with steel factor, were composed of a large proportion (18% to 87%) of CD34(+)/c-kit(+) cells after 1 week, suggesting that either c-kit expression was upregulated or CD34(+)/c-kit(+) cells were produced. Moreover, the CD34(+)/c-kit(-) subfraction was found to be capable of responding to steel factor alone to produce CFU after 4 weeks in SC. In most AML patients tested (11/15), the only sorted subfraction capable of engrafting NOD/SCID mice was CD34(+)/c-kit(-). The CD34(+)/c-kit(+) subfraction from only 2 of the 15 patients and CD34(-) cells from 3 patients also engrafted the NOD/SCIDs. Only the CD34(+)/c-kit(+) subfraction of normal bone marrow engrafted. These studies suggest that primitive AML cells capable of long-term proliferation in vitro and NOD/SCID repopulation differ from primitive normal progenitor cells in their lack of surface expression of c-kit.

Separation of functionally distinct subpopulations of primitive human hematopoietic cells using rhodamine-123.

Normal human bone marrow (BM) contains a small population of cells that can give rise to clonogenic progenitors after 5 weeks in long-term culture (LTC). We have previously shown that these LTC-initiating cells (LTC-IC) differ from the majority of directly clonogenic cells with respect to both light-scattering properties and surface antigen expression. In this paper we show that virtually all LTC-IC (94%) are among the 3%-5% of light-density marrow cells that take up relatively low amounts of rhodamine-123 (Rh-123). In contrast, only 70% of erythroid burst-forming units (BFU-E) and 40% of granulocyte-macrophage colony-forming units (CFU-GM) are recovered in the Rh-123-dull fraction. In addition, we have found that double staining of marrow with Rh-123 and phycoerythrin-labeled anti-CD34 antibodies allows the CD34+ cells to be divided into two subpopulations, of which, on average, 35% are Rh-123-dull. Isolation of these CD34+ Rh-123-dull cells thus provides a single-step enrichment of approximately 240-fold in LTC-IC by comparison to the light-density (less than 1.077 g/cm3) fraction of normal BM. This represents an overall enrichment in LTC-IC of approximately 1000-fold. As expected from the results of staining with Rh-123 only, the majority of directly clonogenic cells are present in the CD34+ Rh-123-bright fraction, where they are enriched approximately 40-fold over their concentration in the light-density fraction. These results indicate marked differences in Rh-123 uptake between subsets of primitive human hematopoietic cells currently defined by different functional assays and suggest that RH-123 staining will be useful for the further purification and analysis of these cells.

The elusive peripheral blood hemopoietic stem cell.

Long-term culture initiating cells (LTC-IC) are primitive hemopoietic progenitors that give rise to clonogenic cells when provided with a supportive feeder layer of mesenchymal cells. These LTC-IC possess many of the characteristics expected of marrow-repopulating "stem cells" including high proliferative and multilineage-differentiative capacity and resistance to 4-hydroperoxy-cyclophosphamide (4-HC) killing. In addition, stem cells are known to persist and may proliferate in murine LTC, and human marrow grown in LTC has been successfully used as hemopoietic support for myeloablative therapy. LTC-IC, as well as clonogenic precursors, circulate in normal peripheral blood, and the concentration of both progenitor types can be increased by cytotoxic chemotherapy and/or growth factors. When mobilized peripheral blood cells are used as hemopoietic support for high-dose chemo/radiotherapy, engraftment has often been more rapid than that achieved with autologous marrow. Thus, primitive hemopoietic cells circulate in human blood, which can enable hemopoietic reconstitution following aggressive therapy for malignant disease.

Specific binding and release of cells from beads using cleavable tetrameric antibody complexes.

A two-step separation procedure is described for the positive selection of cells based on their reactivity with mouse monoclonal antibodies. In the first step cells are specifically cross-linked to hapten-modified glass beads using tetrameric monoclonal antibody complexes. In the second step bound cells are selectively eluted by reductive cleavage of the tetrameric antibody complexes. The latter are comprised of two mouse IgG1 monoclonal antibodies (one recognizing a cell surface antigen on target cells and the other a hapten coupled to the glass beads) bound together by two F(ab')2 fragments of rat anti-mouse IgG1 monoclonal antibody. The complexes provide a specific cleavable cross-link between cell and bead because the disulfide bonds between the two Fab' arms of the F(ab')2 fragments can be broken under relatively mild conditions using dithiothreitol. This specific cleavage of the cross-linker allows elution of the specifically absorbed cells without co-elution of non-specifically bound cells. This is shown in the purification of CD3+ T cells from human peripheral blood, where the removed fractions were over 90% pure and approximately 50% of the positive cells were recovered. Separation of cells labelled with limiting amounts of tetrameric antibody complexes demonstrated that this separation technique was also effective for the purification of cells expressing low amounts of antigens. This was confirmed by the purification of CD34-positive cells from human bone marrow. With this approach, colony-forming cells were enriched 15-24-fold over density separated marrow.

Measurement of the clinical status of patients with breast cancer: evidence for the validity of self assessment with linear analogue scales.

We have assessed the validity of a method of measurement for describing the clinical status of patients with breast cancer. One hundred and nine patients with breast cancer assigned numerical values to their own state of health using linear analogue scales. We have shown previously that this method of measurement is reliable and corresponds well with other methods of assessment. Validity was assessed in this study by examining the ability of measurements to distinguish between groups of patients who differed either in the presence of metastatic disease or in the treatments they were receiving. All patients completed the same set of 29 linear analogue scales that enquired about the severity of health related problems and symptoms. In general, patients with metastatic disease were clearly distinguished from patients without metastases by their scores on items related to physical function. Patients receiving chemotherapy were distinguished from those not receiving chemotherapy by their scores on treatment related toxicities. Measures of psychological and social health were similar in patients receiving chemotherapy regardless of disease status. These results provide further support for the validity of measurement of clinical status with linear analogue scales scored by patients.

Ratings of the importance of quality of life variables: therapeutic implications for patients with metastatic breast cancer.

Metastatic breast cancer cannot be cured with currently available therapeutic agents, and the objectives of treatment must, therefore, be directed towards other goals that include the relief of symptoms and the preservation or restoration of function. The main objective of the study reported here was to examine the relative importance of 28 items concerned with general health or with disease and treatment to a group of patients with metastatic breast cancer. All items concerned aspects of quality of life whose relevance and importance to patients with metastatic breast cancer had been shown in previous work. Patients rated items according to importance using two methods, a Q sort and a linear analogue rating. General health items, notably self-care, mobility, and physical activity, appetite, sleep, and family relationships were ranked in the upper quartile of the group of items rated. By contrast, items concerned directly with the common side-effects of chemotherapy were given lower rankings. The ratings were shown to be reproducible. These results emphasize the importance of including in clinical trials of therapy that are palliative in intent, endpoints that include those aspects of quality of life that are of greatest importance to patients.

The Cooperative Familial Registry for Breast Cancer Studies: design and first year recruitment rates in Ontario.

The Ontario Familial Breast Cancer Registry (OFBCR) is one of six international sites of the Cooperative Familial Registry for Breast Cancer Studies collecting family history, epidemiologic information, and blood samples from families (with various patterns of familial risk) for the purpose of studying the etiology of breast cancer. To invite 2361 female breast cancer patients residing in Ontario to take part in the Registry, a package was sent that included a Family History Questionnaire. Several variations of mailing and follow-up strategies were employed. Overall, the response rate was 67%. The best response (74%) was achieved by following up our introductory package of information with a postcard 10 days later and a telephone call several weeks thereafter. Given the design of the project, which involves a considerable commitment on the part of both patients and their family members, we are impressed by the positive response of these women.

Prolonged survival after intensive therapy and purged ABMT in patients with multiple myeloma.

Despite numerous strategies, the cure of multiple myeloma remains a difficult challenge. Recent approaches have involved dose-intensive therapy followed by stem cell transplantation, most often with autologous stem cells (ASCT). Although ASCT is of benefit, it is not considered curative. Between 1988 and 1995, we utilized an aggressive three-drug conditioning regimen followed by ABMT using marrow purged with either 4-hydroperoxycyclophosphamide (4-HC) or mafosphamide (MAF). Twenty-nine of 42 patients who had first received VAD (14 patients) or VAD followed by cyclophosphamide (7 g/m2 i.v.) + dexamethasone (40 mg/day p.o. x4) + GM-CSF (15 patients) met the eligibility criteria needed to undergo bone marrow harvest and ABMT, ie < or =10% marrow plasma cells and > or =50% decrease in paraprotein level. Alpha-interferon maintenance therapy was given post ABMT. Median follow-up is 7.5 years (range 5.0-11.25). Six early and two late non-relapse deaths occurred; 15 patients have relapsed. Seven patients remain in continuous CR (five) or PR (two), including three with stage IIIB disease at diagnosis. One patient developed a soft tissue sarcoma 8 years post ASCT. Although this protocol produced excessive toxicity compared with current approaches, the results demonstrate that dose-intensive therapy and ASCT can produce durable remission in this disease. Further development of dose-intensive strategies is warranted.

Treatment of myeloma using intensive therapy and allogeneic bone marrow transplantation.

Over a 5-year period we evaluated 65 myeloma patients aged < or = 55 years as potential candidates for intensive therapy and allogeneic BMT. Twenty six (40%) patients were transplanted; the median duration of disease was 4 months (range 2-58 months) and median number of prior regimens was 1 (range 1-5); all but five patients had chemosensitive disease. Conditioning regimens included combinations of BU+CY+MEL in 14 patients, BUCY2 in eight and CY+TBI in four. Donors were HLA-matched siblings in 19 cases, one antigen mismatched siblings in three and unrelated donors in four. All patients received CsA, plus either methylprednisolone (n = 5) or MTX with or without other agents (n = 19). Grade III or IV regimen-related toxicity (RRT) was relatively infrequent (3 patients) and was not seen in nine patients conditioned with BU (total dose 12 mg/kg) + MEL (100 mg/m2) + CY (90 mg/m2). Grade II-IV acute GVHD occurred in 20 patients, and was the cause of death in three. Chronic GVHD also caused three deaths. Thirteen of 21 evaluable patients (62%) achieved a CR and six achieved a PR. Actuarial progression-free survival (PFS) was 40% (95% confidence interval (CI) 19-61%) at a median follow-up of 14 months (range 3-56 months); the PFS was 52% (95% CI 24-74%) in chemoresponsive patients, compared with 0% in chemoresistant patients (P = 0.0066).(ABSTRACT TRUNCATED AT 250 WORDS)

Quantitation of primitive and lineage-committed progenitors in mobilized peripheral blood for prediction of platelet recovery post autologous transplant.

Leukapheresis collections obtained following one of four mobilization regimens from 90 cancer patients were analyzed for their content of various progenitor cell types including erythroid and granulopoietic colony-forming cells in methylcellulose (total CFC), CFC-megakaryocyte (CFC-Mk), CFC detected after 10, 35 and 56 days in long-term culture (LTC), and total CD34+ cells. The number of each of these progenitor cell types collected from individual patients varied over 1000-fold. Nevertheless, within an individual leukapheresis, there was a significant correlation between the number of CD34+ cells and each progenitor type (except day 56 LTC CFC) suggesting that all of them are mobilized by a common mechanism. Patients who had previously received extensive chemotherapy and/or radiotherapy mobilized fewer of all these cell types than those who had not. For the 65 patients who proceeded to autologous transplantation, the median times to an absolute neutrophil count (ANC) of > or =0.5 x 109/l and the last platelet transfusion post transplant were 13 and 11 days, respectively, with 14 (22%) of patients having platelet recovery delayed beyond day 21. There was no significant difference between patients who had or had not received extensive chemo/radiotherapy or among the different mobilization regimens for time to neutrophil or platelet recovery or the number of platelet or red blood cell transfusions received post transplant. Threshold doses of the different cell types transplanted (per kg of patient weight) which predicted rapid platelet recovery were 2 x 106 CD34+ cells, 5 x 105 total CFC and 2.5 x 104CFC-Mk. Corresponding thresholds for progenitor activity measured in LTC could not be established. These results further support the view that standard mobilization regimens yield progenitor numbers that are, in most cases, nonlimiting for generating neutrophil and platelet recoveries within 2 to 3 weeks after myeloablative therapy. Assessment of the CD34+ cell and/or CFC content of leukapheresis collections may identify patients in whom platelet recovery is likely to be significantly delayed although CFC-Mk enumeration does not appear to offer any unique predictive advantage.

Treatment of multiple myeloma with intensive chemotherapy followed by autologous BMT using marrow purged with 4-hydroperoxycyclophosphamide.

In August 1988 we began a program in which multiple myeloma patients achieving < or = 10% marrow plasma cells and > or = 50% reduction in paraprotein levels after the VAD (vincristine, doxorubicin, dexamethasone) regimen underwent bone marrow harvest, ex vivo marrow purging with 4-hydroperoxycyclophosphamide (4-HC) and marrow cryopreservation. Conditioning with a regimen of high-dose busulfan (total dose 16 mg/kg), cyclophosphamide (120 mg/kg) and melphalan (90 mg/m2) (BU + CY + MEL) followed by autologous BMT was then carried out. Seventeen of the 24 patients who received VAD (71%, 95% confidence interval [CI] 49 to 87%) were eligible for bone marrow harvest. One patient was not harvested because of non-medical reasons; two patients who underwent marrow harvest had gross plasmacytosis present in biopsies performed intraoperatively and did not undergo BMT. Fourteen patients (58%, 95% CI 37 to 78%) received BU + CY + MEL and 4-HC-purged autologous BMT. The median time to recovery of 0.5 x 10(9)/l neutrophils was 19 days (range 14 to 26) while the last platelet transfusion was given on a median of day 32 (range 10 to 46) post-BMT in the evaluable patients. The major non-hematologic toxicity was hepatic; two patients in complete remission died of hepatic veno-occlusive disease. Another patient succumbed to fungal infection despite neutrophil recovery. The remaining 11 patients achieved responses (complete in six and partial in five) associated with a normal performance status.(ABSTRACT TRUNCATED AT 250 WORDS)

Human hematopoietic stem cells in long-term culture: quantitation and manipulation.

These results suggest a potentially important role for the LTC system, not only in the development of a quantitative assay for hematopoietic cells, but also clinically as a procedure for manipulating autologous marrow in culture in a variety of ways for therapeutic advantage. These include strategies for immune modulation, gene marking and gene therapy, and perhaps eventually for stem cell amplification.

Quality of life following bone marrow transplantation: a comparison of patient reports with population norms.

All surviving patients who had received an allogeneic bone marrow transplant at the Princess Margaret Hospital were asked to participate in a health-related quality of life (HQL) study using the Medical Outcomes Survey-Short Form 36 (MOS SF-36), the Satisfaction with Life Domains Scale-Bone Marrow Transplantation (SLDS-BMT) and a current symptoms checklist. The main objective was to compare the health status of BMT survivors with age-adjusted population norms. Of the 251 patients contacted, 93% returned questionnaires. The median follow-up after BMT was 40 months, ranging from 1-253 months. On average, survivors had some diminished HQL relative to the health status of the population in general. Time since transplant had a significant influence on HQL; those less than 3 years from transplant experienced considerable impairment while those who had survived beyond this point were indistinguishable from the normal population in most domains and significantly better in certain psychosocial aspects of health. Many patients still reported symptoms months after BMT; some were mildly affected while others experienced more troublesome symptoms. However, 81% of patients were satisfied with the HQL outcome that they had achieved and 94% would recommend a transplant for someone in similar circumstances.