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Biomedical subjects

S D Rowley

Publications and source records attributed to S D Rowley.

At least 19 recordsLinked to original sources
PubMed1992

Hematopoietic stem cell processing and cryopreservation.

Either bone marrow or peripheral blood may be harvested to provide hematopoietic stem cells (HSC) for autologous transplantation. Both, however, comprise heterogeneous cell populations. The HSC necessary for successful engraftment constitute a very small fraction of the cells harvested. After collection, the harvested cells usually undergo several processing steps to reduce the product volume, remove cells (such as mature blood cells or tumor cells), or to cryopreserve the cells for later reinfusion. Granulocytes and red blood cells, for example, survive cryopreservation poorly using freezing techniques designed for HSC. Therefore, bone marrows being cryopreserved must be depleted of mature blood cells to avoid toxicity from infusion of damaged mature blood cells. Mature blood cells may also impede the variety of tumor cell purging techniques currently being studied. These processings are designed to minimize the loss of HSC while achieving an appropriate HSC product for the individual patient. A number of apheresis devices and cell washers simplify the enrichment of HSC in the harvested cell products. In contrast, tumor cell purging techniques are not standardized between the various transplant centers.

Blood Component Removal↗
PubMed1992

Low-temperature storage of bone marrow in nitrogen vapor-phase refrigerators: decreased temperature gradients with an aluminum racking system.

Large temperature gradients may exist in nitrogen vapor-phase refrigerators. Cryopreserved cells stored at higher levels may be considerably warmer than those stored closer to the liquid nitrogen reservoir. To decrease this temperature gradient, racking systems constructed of aluminum were placed in marrow storage refrigerators. The higher heat conductivity of aluminum resulted in a vapor-phase temperature gradient of only 5.9 degrees C at 22.5 inches above the liquid, as compared to the gradient of 86 degrees C seen with steel frames in a similar refrigerator. Temperature fluxes were minimal with lid opening or nitrogen filling. The thicker frame size and loss of the lowest storage level resulted in a storage capacity 63 percent of that achievable with steel frames and liquid immersion. Consumption of nitrogen was estimated to be 174 to 220 percent of the static usage in this model of refrigerator with 6 inches of nitrogen, but comparable to the consumption expected with full immersion of the racking system, regardless of frame construction. These data demonstrate the feasibility of achieving very low, stable, cryogenic temperatures in a vapor-phase refrigerator.

Aluminum↗
PubMed1992

Hematopoietic stem cell cryopreservation: a review of current techniques.

Hematopoietic stem cells (HSC) can be stored for prolonged periods at cryogenic temperatures. The techniques currently used were derived from the initial report in 1949 of cryopreservation of bovine sperm in glycerol. The addition of this penetrating cryoprotectant protected the cells from the injury associated with ice formation. Current cryopreservation techniques (with minor variations) suspend cells in an aqueous solution of salts, protein, and one or more cryoprotectants. Cells are frozen at slow rates and stored generally below -120 degrees C in mechanical freezers or nitrogen refrigerators. That these techniques are successful in maintaining HSC viability is evident from the engraftment of these cells in patients treated with marrow-lethal conditioning regimens. However, issues such as the composition of the cryoprotectant solution, cell concentration during freezing, cryoprotectant toxicity, and storage temperatures have not been adequately studied, primarily because of a lack of appropriate assays for HSC cryosurvival. HSC cryobiology will become an increasingly important subject as new HSC collection and processing techniques are developed. Improved cryosurvival of HSC using modified cryoprotectant solutions may improve engraftment kinetics and decrease the cost and morbidity of autologous transplantation.

Bone Marrow Cells↗
PubMed1991

Correlation of occult clonogenic leukemia drug sensitivity with relapse after autologous bone marrow transplantation.

Despite initial complete remission rates exceeding 70%, the majority of patients with acute myeloid leukemia (AML) and adults with acute lymphocytic leukemia (ALL) eventually relapse. Improving the therapeutic results in acute leukemia requires detecting, and understanding the biology of, the minimal residual leukemia remaining after therapy and responsible for relapse. To investigate the biologic relevance of an in vitro assay for clonogenic leukemia (leukemia colony-forming units [CFU-L]) as a measure of minimal residual leukemia, we studied 58 consecutive patients with acute leukemia in complete remission undergoing autologous bone marrow transplantation (BMT) with cyclophosphamide-based therapy. CFU-L were cultured from the pretransplant remission marrows in 45 of 58 patients: 35 of 43 patients with AML and 10 of 15 with ALL. Clonal rearrangements, identical to the patients' overt leukemia when available, were detected in the occult CFU-L from four of the eight patients with ALL in whom adequate DNA for analysis could be obtained from the CFU-L. None of the uncultured pretransplant remission marrows from the 15 ALL patients showed clonal gene rearrangements. We also determined the in vitro sensitivity of the occult CFU-L to 4-hydroperoxycyclophosphamide (4HC), and correlated these results with the outcome of the patients. The sensitivity of the occult CFU-L to 4HC was the only factor that predicted relapse following BMT. The actuarial probability of relapse was 18% in the 23 patients whose CFU-L were sensitive to 4HC compared with 77% in the 22 patients whose CFU-L were resistant (P less than .001). The only factor that influenced the CFU-L sensitivity to 4HC was the type of leukemia. The CFU-L from the AML patients were more sensitive to 4HC than the CFU-L from the ALL patients (P = .001). Occult CFU-L genetically and functionally represent occult leukemia. Therefore, the CFU-L assay should provide a means for studying the biology of minimal residual leukemia and improving the therapeutic results in patients with acute leukemia.

Adolescent↗
PubMed1991

High-dose chemotherapy with reinfusion of purged autologous bone marrow following dose-intense induction as initial therapy for metastatic breast cancer.

We assessed the toxicity and efficacy of high-dose chemotherapy consolidation with reinfusion of purged autologous bone marrow in women with metastatic breast cancer responding to a dose-intense outpatient regimen. Thirty women with hormone-unresponsive metastatic breast cancer, previously untreated with adjuvant doxorubicin or with any chemotherapy for metastatic disease, were treated with cyclophosphamide, methotrexate, doxorubicin, fluorouracil, vincristine, and leucovorin for 16 weeks. Twenty-four patients responded to therapy; 8 showed a complete response, and 16 showed a partial response. These patients proceeded to the next phase of the protocol, ie, marrow harvest and treatment with 6000 mg/m2 cyclophosphamide and 800 mg/m2 thiotepa given over 4 days. Harvested marrow was purged with 100 micrograms/mL 4-hydroperoxycyclophosphamide, and all patients engrafted satisfactorily. The predominant side effects were myelosuppressive and gastrointestinal, and there were no deaths from toxic effects. Three of the 16 patients who showed a partial response after the outpatient phase of treatment achieved a complete response after high-dose therapy. The partial response seen in two more patients converted to a complete response at all sites except bone. The median time to disease progression for all patients in this study was 13 months, and the median survival was 22 months. Four of the original 30 patients remained without disease progression a median of 27 months from entry into the study. This study indicates that this dose-intense regimen can be safely administered, even with the use of purged marrow, with an acceptable toxicity profile. This approach results in a high response rate in women with metastatic breast cancer and could form the basis for a regimen to be tested in the high-risk adjuvant setting.

Adult↗
PubMed1991

Selection of normal human hematopoietic stem cells for bone marrow transplantation using immunomagnetic microspheres and CD34 antibody.

Complete yet nontoxic removal of tumor cells from autologous marrow grafts has proved difficult. New methods for separating normal stem cells from tumor cells are needed. The CD34+ cells in bone marrow, 1-2% of the low-density leukocytes, include precursors of all lymphohematopoietic lineages and probably also the primitive cells responsible for engraftment. A nontoxic, inexpensive, reproducible, and clinically applicable method for positive selection of CD34+ cells was developed. Paramagnetic microspheres coated with goat anti-mouse IgG1 are used to partition the cells; brief incubation with chymopapain is used to release them from the beads. Chymopapain exposure does not injury colony-forming cells or delay engraftment in rodents. Clinical volumes of bone marrow can be processed rapidly. In pilot experiments, the resulting grafts have a purity of 85-99% CD34+ cells and 40% median recovery of the assayable colony-forming cells. These studies form the background for a Phase I trial of autologous BMT using CD34+ stem cells.

Animals↗
PubMed1991

Phase I study of combination drug purging for autologous bone marrow transplantation.

In a phase I clinical trial of autologous bone marrow transplantation, we determined the feasibility of ex vivo purging with high concentrations of pharmacologics in combination. Light-density cells isolated from the grafts of 26 patients with acute leukemia or lymphoblastic lymphoma were treated with 4-hydroperoxycyclophosphamide (4-HC; 30 to 60 micrograms/mL), vincristine (Vcr; 1.5 to 3.0 micrograms/mL), and methylprednisolone sodium succinate (MP; 5 mg/mL). All patients received marrow-lethal induction therapy followed by infusion of the treated grafts. Three patients died of transplant-related complications before achieving peripheral blood recovery of greater than 0.5 x 10(9) granulocytes per liter. All other patients achieved this parameter of engraftment at a median of 35 days after marrow infusion. The median time to last platelet transfusion was 45 days. These durations of aplasia were similar to those experienced by other patients receiving density-gradient separated grafts treated with 60 micrograms/mL of 4-HC as a single agent. No patient required infusion of untreated reserve marrow because of engraftment failure. The colony-forming unit-granulocyte macrophage (CFU-GM) content of the grafts after purging predicted these parameters of engraftment. Colony-forming unit-leukemia (CFU-L) cultured from the grafts of 12 of the patients treated for acute lymphoblastic leukemia (ALL) were considerably more sensitive to the combination regimen than to 4-HC alone; the sensitivity of CFU-GM from these patients did not differ between the two regimens. The results of this trial indicate the feasibility of treating autologous bone marrow grafts with high concentrations of pharmacologics in combination. The use of combinations may increase the efficacy of ex vivo purging without increasing the toxicity to normal hematopoietic cells.

Adolescent↗
PubMed1991

Analysis of factors predicting speed of hematologic recovery after transplantation with 4-hydroperoxycyclophosphamide-purged autologous bone marrow grafts.

We previously described the predictive value of graft colony-forming units granulocyte macrophage (CFU-GM) content after 4-hydroperoxycyclophosphamide (4-HC) purging for the duration of aplasia after autologous bone marrow transplantation. Despite the uniform 4-HC concentration, we observed heterogeneity in CFU-GM survival and the kinetics of engraftment. We have now analysed patient and graft characteristics for 154 patients undergoing autologous transplantation with 4-HC purged grafts to further define this heterogeneity. Patients transplanted for the treatment of malignant lymphoma reached a peripheral blood granulocyte count of greater than 0.5 x 10(9)/l (median, 20 versus 40 days; p less than 0.001) and platelet transfusion independence (median, 30 versus 70 days; p less than 0.001) significantly faster than patients transplanted for acute non-lymphoblastic leukemia. Other diagnostic groups were intermediate. These differences were independent of graft CFU-GM content. Multiple other patient and graft factors including patient age, peripheral blood counts on day of harvest, and amounts of other hematopoietic progenitors also predicted the kinetics of engraftment in univariate and multivariate analysis. Cytomegalovirus infection during the aplastic period predicted a delay in granulocyte (p = 0.024) but not platelet recovery (p = 0.174). This analysis demonstrates that multiple patient, graft, and post-transplant factors predict the engraftment capacity of autografts, and the kinetics of engraftment with 4-HC purged grafts. The multiple predictive factors explain a significant portion of the variability in engraftment kinetics observed after transplantation with 4-HC purged autografts.

Adolescent↗
PubMed1990

Bone marrow graft engineering by counterflow centrifugal elutriation: results of a phase I-II clinical trial.

In an attempt to reduce the incidence and severity of acute graft-versus-host disease (GVHD), we have decreased the number of bone marrow (BM) lymphocytes in the donor marrow graft before bone marrow transplantation (BMT) using counterflow centrifugal elutriation (CCE). In a phase I-II clinical trial, 23 patients received lymphocyte-depleted BM allografts from their HLA-identical, mixed lymphocyte culture (MLC)-nonreactive sibling donors. The patients entered in the study were deemed to be at high risk for treatment failure on the basis of age (greater than 30 years; median, 39 years) and the result of our skin explant assay predictive of acute GVHD. Patients predicted not to develop acute GVHD by this assay were excluded from this study. All patients received a standard lymphocyte dose of 0.5 x 10(6) morphologic lymphocytes per kilogram ideal body weight (IBW) in the marrow graft and were maintained on cyclosporine A (CsA) immunosuppression for 170 days after BMT. Prompt hematopoietic recovery occurred in 22 of 23 patients with a median time to an absolute neutrophil count (ANC) greater than or equal to 500/microL of 21 days. Donor cell engraftment was subsequently verified by cytogenetic and/or DNA analysis in all of 21 evaluable patients. No patient developed systemic acute GVHD. Only five (22%) developed cutaneous GVHD (clinical stage 1) that required steroid treatment, including one patient who failed to engraft. The median follow-up of the patients enrolled in this study is 14 months (range, 5 to 20 months). Actuarial survival 1 year after BMT is 83%. Thus, in two consecutive clinical trials using CCE to deplete donor BM of alloreactive lymphocytes (1.0 x 10(6) versus 0.5 x 10(6) lymphocytes/kg), we have demonstrated that the procedure does not interfere with BM engraftment and is effective in decreasing the incidence and severity of acute GVHD. Furthermore, comparison of these studies has revealed a differential dose response relationship between the number of graft lymphocytes, protection of engraftment, and induction of acute GVHD. Although there appears to be a modest relationship between lymphocyte dose and time to hematopoietic recovery, the 50% reduction in lymphocyte dose from that used in our previous trial resulted in a marked decrease in acute GVHD without compromising engraftment.

Adult↗
PubMed1990

Clinical toxicity of cryopreserved bone marrow graft infusion.

We prospectively evaluated infusion-related toxicities in 82 recipients of autologous bone marrow grafts. The grafts were cryopreserved in 10% dimethylsulfoxide and stored in liquid nitrogen. All grafts were concentrated and buffy-coat cells were collected. Forty-seven grafts were treated ex vivo with 4-hydroperoxycyclophosphamide (4-HC) at 100 micrograms/mL; 26 grafts were further processed using density-gradient separation and treated with 4-HC at 60 micrograms/mL. Nine buffy-coat concentrates were frozen without drug treatment. Before infusion, patients were medicated with mannitol, hydrocortisone, and diphenhydramine. Grafts were rapidly thawed and immediately infused without further manipulation. During the infusions, 33 (70%) recipients of treated buffy-coat, 5 (56%) recipients of untreated buffy-coat, and 6 (23%) recipients of density-gradient separated grafts experienced varying symptoms including nausea, abdominal cramping, and flushing. Forced vital capacities for 83% of the recipients of treated buffy-coat concentrates decreased after the graft infusion; six of these patients complained of dyspnea and one patient experienced an acute episode of respiratory decompensation. Decreased heart rates were observed in 98% of the recipients of treated buffy-coat cells with asymptomatic bradycardia occurring in 45%. Forty-five patients (96%) in this group experienced transient hypertension, with 18 (38%) requiring additional medications within 6 hours after the infusion for control of blood pressure. Similar cardiovascular changes were observed in the recipients of untreated buffy-coat concentrates. One recipient of an untreated buffy-coat concentrate had 2 degrees heart block after the graft infusion. Twenty-three (88%) recipients of density-gradient separated grafts had decreased heart rates and 21 (81%) had increased blood pressure. However, the degrees of change were less than those experienced by the recipients of treated buffy-coat cells (P less than .01). Forced vital capacities were not affected by the infusion of the density-gradient separated grafts. No renal failure or obvious hemolytic episodes occurred for any patient group. Minor to moderate toxicities were associated with cryopreserved graft infusions. Recipients of buffy-coat separated grafts, both treated and untreated, experienced more complications than the recipients of density-gradient separated grafts. These toxicities may relate to the volumes of cryoprotectant and cell lysis products infused, which were less for the more highly purified density-gradient separated grafts.

Blood Chemical Analysis↗
PubMed1990

Ex vivo chemopurging of autologous bone marrow with 4-hydroperoxycyclophosphamide to eliminate occult leukemic cells. Laboratory and clinical observations.

The application of autologous bone marrow transplantation (ABMT) in treating acute leukemias in children has been limited by the presence of residual occult viable leukemic cells in the marrow cell suspension. One approach to this problem is the ex vivo treatment ("purging") of the autograft to eradicate these tumor cells yet spare the normal lymphohematopoietic stem cells. Initial studies of acute myeloid leukemia (AML) in a rodent model demonstrated that incubation with 4-hydroperoxycyclophosphamide (4HC), a congener of cyclophosphamide and an active alkylating agent in aqueous solution, could effectively eliminate viable AML cells from marrow cell suspensions without apparent toxicity to normal stem cells. We have conducted clinical trials of ABMT with 4HC-treated marrow in children with acute leukemia in remission; marrow was collected, treated ex vivo with 4HC (100 micrograms/ml), and cryopreserved in liquid nitrogen until reinfusion. Children received pre-ABMT conditioning with either high-dose cyclophosphamide and total body irradiation (CY-TBI) for acute lymphocytic leukemia (ALL) or high-dose busulfan and cyclophosphamide (BU-CY) for AML. Of nine children who underwent ABMT with 4HC-treated marrow for ALL in second complete remission (CR2), all relapsed (eight in the marrow, one in the central nervous system) at a median of 5 months (range, 2-17) after ABMT and all have died with relapsed ALL or as a consequence of its treatment. Twenty-nine children with AML (five in CR1, 24 in CR2) received autografts with chemopurged marrow at a median remission duration of 3 months (range, 2-15). Three patients died from sepsis during aplasia; 10 children (one in CR1 and nine in CR2) relapsed with AML at a median of 7 months (range, 2-23) after ABMT, for an actuarial relapse rate of 47%. Sixteen patients with AML (four in CR1, 12 in CR2) are in unmaintained remission at a median of 16 months (range, 6-102) after ABMT, for an actuarial disease-free survival of 49%. Although ABMT with 4HC-treated marrow appears to have a limited role in the treatment of children with ALL who lack a suitable related donor, the results in AML are encouraging and compare favorably with both syngeneic and allogeneic BMT in similar groups of patients.

Actuarial Analysis↗
PubMed1990

High-dose cytotoxic therapy and bone marrow transplantation for relapsed Hodgkin's disease.

Patients with Hodgkin's disease who have failed two or more chemotherapy regimens or who have relapsed after an initial chemotherapy-induced remission of less than 12 months are seldom cured with conventional salvage therapies. We studied the effect of high-dose cytoreductive therapy followed by bone marrow transplantation in 50 such patients with relapsed Hodgkin's disease. Twenty-one patients with histocompatibility locus antigen (HLA)-matched donors had allogeneic marrow transplants, one patient received marrow from an identical twin, and 28 patients without a matched donor received autologous grafts purged with 4-hydroperoxycyclophosphamide. Busulfan plus cyclophosphamide was the preparative regimen for the 25 patients who had received extensive prior irradiation, and the other 25 patients received cyclophosphamide plus total body irradiation. The overall actuarial probability of event-free survival at 3 years was 30%, with a median follow-up of 26 months. The event-free survival following transplantation was influenced by the number of chemotherapy failures and the patient's response to conventional salvage therapy prior to transplant. The 16 patients who were transplanted at first relapse, while still responsive to standard therapy, had a 64% actuarial probability of event-free survival at 3 years. Age, presence of extranodal disease, preparative regimen, and type of graft (autologous v allogeneic) were not significant prognostic factors. The majority of transplant-related deaths were from interstitial pneumonitis; inadequate pulmonary function, multiple prior chemotherapy regimens, and prior chest irradiation all appeared to increase the transplant-related mortality. These results suggest a role for marrow transplantation in a subset of patients with relapsed Hodgkin's disease who are unlikely to be otherwise cured but are still responsive to conventional-dose cytoreductive therapy.

Actuarial Analysis↗
PubMed1990

Using elutriation to engineer bone marrow allografts.

We have used elutriation to deplete lymphocytes from the marrow allografts of 64 patients to date. The first phase I trial (1 x 10(6) lymphocytes/kg IBW) was designed to test the procedure for potential toxicities, most notably, graft failure. Study 2 (1 x 10(6) lymphocytes/kg, no CsA) was expected to reduce potential toxicity incurred from long term immunoprophylaxis while study 3 was aimed at reducing the incidence of GVHD by further reducing lymphocyte dose (5 x 10(5)/kg). Graft lymphocyte dose was based on morphologic determination and was subsequently confirmed by limiting dilution analysis and flow cytometry. Although grafts were standardized solely by lymphocyte dose, the product was more uniform than the original harvested BM with respect to other cell populations. Nearly all study I (n = 40) and study III (n = 20) patients engrafted with a median time to ANC greater than 500/ul of 19 days. Three of the 4 patients consecutively enrolled in study II failed to engraft, thus terminating the trial. While a moderate proportion of study I patients had AGVHD (44%) with attendant morbidity, only 20% of study III patients were found to have mild AGVHD (less than or equal to stage I). To date, this cohort has no organ or chronic GVHD and no GVHD-associated morbidity. Median follow-up times for patients in studies I and III are 27 and 11 months, respectively. Overall actuarial survival (n = 60) is 42% at 38 months (38% study I, 80% study III). Good prognosis study I patients experienced 45% actuarial survival versus 9% in the poor prognostic group. While lymphocyte depletion has been effective in reducing the incidence and severity of AGVHD, new strategies are needed to address the issue of disease relapse. As with other methods, lymphocyte depletion by elutriation caused an increased rate of leukemia relapse. The actuarial probability of remaining in remission for recipients of elutriated marrow containing 1 x 10(6) and 5 x 10(5) lymphocytes/kg, respectively, were 60% and 46% at 16 months. Elutriation provides a rapid, reproducible and flexible methodology for graft manipulation which has been effective in reducing the incidence and severity of AGVHD. However, if lymphocyte depletion is to fulfill its promise as a means of reducing the overall morbidity of allogeneic BMT, new strategies may be needed to address the issue of relapse. These may include changes in marrow ablative therapy and post-graft immunosuppression. Equally as important may be the ability to further manipulate accessory cells and lymphoid populations presently excluded from the graft.

Adult↗
PubMed1990

Density-gradient separation of autologous bone marrow grafts before ex vivo purging with 4-hydroperoxycyclophosphamide.

We found in previous studies that the cytotoxicity of 4-hydroperoxycyclophosphamide (4-HC) toward normal and malignant cells in autologous bone marrow grafts was modulated by the variable erythrocyte content of the incubation mixture. This affected both the kinetics of engraftment and the probability of leukemic relapse. To decrease this variability in 4-HC cytotoxicity, we initiated a trial of density-gradient separation of the autografts to remove erythrocytes and other mature blood cells before the 4-HC treatment. A series of 64 consecutive patients was studied. Light-density (sp. gr. much less than 1.077 g/ml) cells were isolated in a 2-step procedure by Ficoll-diatrizoate separation of previously isolated buffy-coat cells. Overall cell recovery after buffy-coat and gradient separations was 28.9 +/- 11.7% ( +/- SD). These cells were then treated with 60 micrograms/ml of 4-HC. The erythrocyte content of the incubation mixtures averaged 0.8%, and did not predict percent CFU-GM survival after the 4-HC incubation. The variability in CFU-GM survival after the purge was less than for previous patients who received buffy-coat cells (with erythrocyte contents ranging from 4-22%) treated with 100 micrograms/ml of 4-HC, indicating that a more uniform purge was achieved. Although the selected dose of 4-HC (60 micrograms/ml) yielded a lower CFU-GM survival, the kinetics of engraftment did not significantly differ between the recipients of light-density or buffy-coat cells. No patient required use of a 'backup' graft because of engraftment failure.

Adolescent↗
PubMed1990

Toxicity of autologous bone marrow graft infusion.

We prospectively evaluated infusion-related toxicities in 70 patients undergoing autologous bone marrow transplantation. We studied symptoms, vital signs, forced vital capacities, and serum chemistry changes associated with the infusion. The bone marrow grafts were cryopreserved in 10% dimethylsulfoxide (DMSO) and stored in liquid nitrogen. All grafts were concentrated by centrifugation and the buffy-coat cells collected. Additionally, 20 grafts had mononuclear cells collected using density-gradients. Before infusion, the patients were medicated with hydration, mannitol, hydrocortisone, and diphenhydramine. The grafts were rapidly thawed and immediately infused without further manipulation. The mean volume infused to patients who received buffy-coat grafts was 6.3 +/- 1.7 ml/kg containing 0.7 +/- 0.2 gm/kg of DMSO. Patients who received density-gradient separated grafts received a product with a volume of 2.9 +/- 1.3 ml/kg containing 0.3 +/- 0.1 gm/kg DMSO. Symptoms included nausea, abdominal cramping, and flushing; patients who received buffy-coat grafts had more complaints. These patients also had mild increases in AST, ALT, and total bilirubin. Forced vital capacities were decreased in this group after the graft infusion; this change was not associated with the infusion of the density-gradient separated products. There was a significant difference (p less than 0.01) in heart rate and blood pressure changes associated with the infusions. Patients who received the larger product had a minimum heart rate of 63.3 +/- 12.4 BPM as compared to 80.7 +/- 18.0 BPM for the other patients. We found minor to moderate toxicities associated with the graft infusions, which were more severe in patients who received buffy-coat grafts. This could have resulted from the greater amounts of DMSO, cell lysis products, or volumes infused.

Adolescent↗
PubMed1990

In vitro evaluation of combination drug purging for autologous bone marrow transplantation.

Using an in vitro model, we studied whether combining 4-hydroperoxycyclophosphamide (4HC) with other drugs could improve its effectiveness as an ex vivo purging agent for autologous bone marrow transplantation. 4HC was incubated simultaneously with vincristine and etoposide, and sequentially with methylprednisolone, in various combinations. Compared to 4HC alone, all drug combinations increased the kill of the leukemia cell lines K562 and CEM without increasing the kill of granulocyte-macrophage colony-forming units (CFU-GM). The combination of 4HC, vincristine and methylprednisolone was the most active, and this drug combination was also the only combination which showed improved selective cytotoxicity (compared to 4HC alone) toward REH cells. This combination inhibited at least 8 logs of clonogenic leukemia cells from all three cell lines at doses which spared 1% of CFU-GM. This was an increase of 1.7 to 6.6 logs of clonogenic leukemia cell kill over 4HC alone. This drug combination displayed similar differential activity between fresh clonogenic leukemia cells and CFU-GM cultured from the bone marrows of seven patients about to undergo autologous bone marrow transplantation for acute lymphocytic leukemia.

Antineoplastic Combined Chemotherapy Protocols↗