Autografting in chronic myeloid leukemia with cultured marrow: update of the Vancouver Study

When chronic myeloid leukemia (CML) marrow is set up in long-term culture (LTC), Philadelphia chromosome (Ph)-positive (Ph+) cells typically decline and Ph-negative (Ph-) hematopoietic cells often become detectable. In 1987, we initiated a study to evaluate the feasibility of using 10-day cultured marrow autografts to allow intensive treatment of CML. Patients were selected on the basis of a previous assessment of the frequencies of normal and leukemic LTC-initiating cells (LTC-IC) remaining in their marrow after 10 days of LTC. Of the 87 patients evaluated, 36 (41%) were considered eligible, and 22 (15 in first chronic phase [CP], Group 1; and 7 with more advanced disease, Group 2) were autografted with 10-day cultured marrow after intensive therapy. Satisfactory hematological recovery occurred in 16 patients, and of these, only Ph- cells were detected in 13 (nine in Group 1), with 76-94% Ph- cells in the other three (two in Group 1). Ph+ cells reappeared between 4 and 36 months post-autograft in all but one of the 13 patients in whom complete (morphological and cytogenetic) remission had been achieved; the remaining patient died in remission. Nine of these twelve patients were then treated with alpha-interferon (IFN-alpha) 1-3 x 10(6) units/m2, 3-7 days/week; four returned to complete remission, three developed increasing numbers of Ph+ cells, and two are still too early to evaluate. Fifteen patients (12 in Group 1) remain alive and well, nine in hematological remission (eight in Group 1), 9 to 64 months (median 28) post-autograft.(ABSTRACT TRUNCATED AT 250 WORDS)

Culture of normal and leukemic bone marrow in interleukin-2: analysis of cell activation, cell proliferation, and cytokine production

Transplantation of bone marrow autografts activated by culture in interleukin-2 (IL-2) followed by administration of IL-2 represents a novel approach in an attempt to combine ex vivo purging and post-transplant in vivo immunotherapy, and initial clinical results have suggested its feasibility. To further characterize the mechanism of the in vitro anti-leukemia effect, fresh bone marrow from normal donors and from patients with acute myelogenous leukemia (AML) in remission was cultured for 6 days in the absence or presence of IL-2 (1000 IU/ml). Proliferation of CD3, CD8, CD14, and CD56 cells was determined by direct immunofluorescence using flow cytometry. Predominantly T-lymphocytes (CD3+) and to a lesser extent CD56+ natural killer (NK) cells proliferate in 6-day marrow cultures in IL-2. Fresh bone marrow cells have no measurable NK activity when tested against K562 and Daudi target cell lines in a 4 h chromium-51 release assay, and it requires at least 6 days of culture in IL-2 to develop optimal cytotoxic activity. Cytokines released in the supernatants of these cultures were measured by immuno- and bioassays. Tumour necrosis factor alpha (TNF-alpha), interferon gamma (IFN-gamma), and IL-6 were found to be produced in significant amounts by marrow mononuclear cells during culture in IL-2. Even without IL-2 present, concentrations of these cytokines were increased in 6-day marrow cultures. In contrast, IL-3, IL-7, granulocyte and granulocyte-macrophage colony-stimulating factors (G-CSF and GM-CSF) were below the level of detection of the immunoassay, a result that could be confirmed for GM-CSF and IL-3 by bioassay. The data suggest that culture of marrow from normal donors as well as from patients with AML obtained in remission can generate anti-leukemia effector mechanisms which are non-crossreactive with chemo- and radiotherapy and may contribute to effective ex vivo purging of residual leukemic cells. The transplantation of such IL-2 'primed' marrow may also contribute to an in vivo graft-versus-leukemia effect.

High-dose chemotherapy and autologous bone marrow transplantation for patients with poor prognosis nonseminomatous germ cell tumours

Twenty-one patients with poor prognosis nonseminomatous germ cell tumours (six with extreme burden disease at presentation in whom partial remission had been achieved with initial induction therapy, and 15 with recurrent disease after induction therapy) were treated with high-dose chemotherapy and autologous bone marrow transplantation (BMT). The first six received etoposide 3.0 g m-2, ifosfamide 6.0 g m-2 and carboplatin 1.2 g m-2 (Regimen 1), and the subsequent 15 received etoposide 2.4 g m2 (continuous infusion), cyclophosphamide 7.2 g m-2 and carboplatin 0.8 g m-2 (Regimen 2) followed by infusion of previously stored autologous marrow. Regimen 1 was associated with considerable renal toxicity and mucositis, whereas Regimen 2 was relatively well tolerated. Two patients died as a consequence of the treatment: one of candidemia and one of interstitial pulmonary fibrosis. Only one of 17 patients who were autografted in or approaching marker remission subsequently developed disease progression (event-free survival 82%, 95% confidence interval [CI] 55% to 94%), whereas all four patients who had progressive disease at autografting subsequently developed further disease progression and died. Fourteen patients remain well and free of disease 0.5 to 6.5 years (median 3.3) post-BMT (event-free survival 67%, 95% CI 43% to 83%). A strategy of prompt reinduction followed by high-dose chemotherapy and autologous BMT at the first sign of failure of standard therapy may allow cure to be a realistic expectation.

Design and validation of a clinically applicable culture procedure for the generation of interleukin-2 activated natural killer cells in human bone marrow autografts

Previous studies in animal models have suggested that bone marrow-derived interleukin-2 (IL-2) activated natural killer (A-NK*) cells can be used to eliminate residual leukemic cells both in vivo and in vitro. As part of initial studies to develop a clinical protocol to exploit this phenomenon in combination with culture purging of leukemic cells, we examined a number of variables that might affect either IL-2 stimulation of natural killer (NK) cell activity or maintenance of primitive hematopoietic cells in cultures suitable for manipulating human marrow autografts. Cytotoxicity of IL-2 A-NK cells was determined using K562 and Daudi target cells in a standard 4-hour 51Cr release assay. Primitive hematopoietic cells were quantitated using both direct clonogenic progenitor assays and the long-term culture-initiating cell (LTC-IC) assay. The latter measures a very primitive cell type that gives rise to clonogenic cells after > 5 weeks of culture on pre-established marrow feeder layers. Light-density (< 1.070 g/cm3) human marrow cells cultured at 10(6) cells/mL for 7 days at 37 degrees C in the presence of 1000 U of either natural or recombinant human IL-2 showed a marked generation of A-NK cell function that was not seen if IL-2 was not added. The cytotoxicity was the same whether the cells had been maintained in standard fetal calf serum (FCS)-supplemented medium or in LTC medium (which also contains horse serum and 10(-6) M hydrocortisone) or whether adherence of cells during the culture period was promoted or prevented. The level of NK activity in IL-2-stimulated cultures of marrow cells from patients with acute myeloid leukemia (AML) in remission was not significantly different from that obtained with normal marrow. The initial numbers of clonogenic cells in these samples were close to normal values (60%). For both normal and AML patient samples, these declined slightly during the 7-day culture period, regardless of whether IL-2 was present. Starting values for LTC-IC in patient marrow samples were markedly reduced to approximately 7% of normal values, but as in normal cultures, did not decrease further in culture with or without IL-2. These results indicate that activation of bone marrow-derived NK cells can be obtained in 7-day cultures containing IL-2 under conditions that preserve the most primitive hematopoietic cells currently detectable.

Response of therapy-related myelodysplasia to low-dose interleukin-2

We report the case of a patient treated with interleukin-2 (IL-2) for refractory anemia with excess blasts (RAEB), which developed during third complete remission of acute lymphoblastic leukemia. IL-2 was given subcutaneously at 2.5 x 10(5) IU (= 10(5) BRMP units) twice daily for 30 days. During treatment spontaneous natural killer (NK) activity was enhanced, circulating lymphokine-activated killer effector cells became detectable and CD56+/CD3- NK cells in the blood doubled. The response in the bone marrow was a reduction in myeloid blast cells (from 7 to 0%), ringed sideroblasts (from > 15 to 0%) and dysplasia (from trilineage to minimal megakaryocytic), and a decrease in metaphases with the RAEB karyotype (from 43 to 2%). Toxicity of IL-2 was minimal. Thus a relatively low dose of IL-2 caused immune activation and resulted in significant hematologic and cytogenetic response in this case of therapy-related myelodysplasia.

Induction therapy for acute myelogenous leukemia in patients over 60 years with intermediate-dose cytosine arabinoside, mitoxantrone and etoposide

Twenty-three patients greater than age 60 years with acute myelogenous leukemia (AML) received induction therapy with continuous infusion cytosine arabinoside (1.5 g/m2/day, day 1-3), mitoxantrone (10 mg/m2/day, day 1-3) and etoposide (800 mg/m2, day 4). Patients entering complete remission (CR) were eligible to receive an identical consolidation cycle. Eighteen of the 23 patients (78%; 95% confidence interval 56% to 93%) entered CR. Twelve of these received consolidation therapy and 4 of these remain in remission at 3 to 20 months. Hematologic toxicity of the regimen was acceptable; only 1 patient died following therapy (having attained a CR). Non-hematologic toxicity was mostly mild (grade 2 or less) with one episode of grade 3 cerebellar toxicity. While this regimen induces a high CR rate in patients > age 60 years, relapses remain common and overall survival is too early to assess.

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)

Chemotherapy with high-dose cytosine arabinoside and mitoxantrone for poor-prognosis myeloid leukemias

Forty-seven patients with poor-prognosis myeloid leukemias received induction therapy with high-dose cytosine arabinoside (HDara-C), 1.5-3.0g/m2 for 8-10 doses, and mitoxantrone (DHAD), 12-15 mg/m2 for 3 doses. Complete remissions were achieved in 21 [45%, 95% confidence interval (CI) 30.2-59.9%] of the patients, including 11 of 14 with acute myelogenous leukemia (AML) in first relapse (79%, 95% CI 49.2-95.3%), 4 of 8 with refractory anemia with excess blasts in transformation (RAEBiT) (50%, 95% CI 15.4-84.6%), and 4 of 6 (67%, 95% CI 22.3-95.7%) previously untreated elderly AML patients. Patients with secondary AML and advanced chronic myelogenous leukemia had a very low response rate. The incidence of reversible toxicity was low and only 3 treatment-related deaths occurred. After reinduction, 8 of 9 AML patients < or = 60 years of age were ultimately able to undergo intensive therapy and either autologous 4-hydroperoxycyclophosphamide-purged bone marrow (7 patients) or peripheral blood stem cell (1 patient) transplantation with satisfactory hematological recovery. We conclude that HDara-C and DHAD is an effective antileukemic regimen in selected AML and RAEBiT patients, and that its use may allow subsequent successful autologous BMT in appropriate patients.

Trying to overcome residual disease after bone marrow transplantation for hematologic malignancies

Relapse after marrow transplantation occurs despite total body irradiation and high doses of chemotherapy used to prepare the recipient. Recurrence rate is particularly high after autologous transplantation. In order to eliminate minimal residual disease persistent after marrow grafting, immunotherapy is currently being explored as a treatment modality that is non-cross-reactive with radiation and chemotherapy. This review describes first clinical results on the use of interferons and interleukin-2 in marrow transplant recipients as well as attempts to induce graft-versus-leukemia effects.

Treatment of myelodysplastic syndrome with busulfan-cyclophosphamide conditioning followed by allogeneic BMT

Twenty-three consecutive patients undergoing related-donor BMT for myelodysplastic syndrome (MDS) were conditioned with a combination of busulfan (BU) and cyclophosphamide (CY). GVHD prophylaxis was with cyclosporine (CSP)/methotrexate (MTX) in 15 patients, CSP/methylprednisolone (MP) in six patients, and CSP/MP/MTX in two patients. The most frequent regimen-related toxicities were oral mucosal (87% of patients, 61% > or = grade II) and hepatic (82% of patients, 43% > or = grade II). The overall incidence of grade II-IV acute GVHD was 48% with eight patients dying of acute or chronic GVHD. There have been five relapses, with the cumulative risk of relapse being 35% (95% confidence interval [CI], 16%-66%). Eight patients remain alive and well (median follow-up 27 months, range 15-70 months), with an estimated 3-year event-free survival (EFS) of 35% (95% CI, 17%-54%). Univariate analysis of EFS by pretransplant variables indicated that only age < or = 35 years correlated with a favorable outcome (p = 0.04). BUCY is an effective, well-tolerated alternative conditioning regimen for MDS patients undergoing allogeneic BMT.

Anti-interleukin-2 receptor monoclonal antibody (BT 563) in the treatment of severe acute GVHD refractory to systemic corticosteroid therapy

Fourteen patients with corticosteroid-resistant acute GVHD were treated with a murine monoclonal antibody to the pp55 interleukin-2 (IL-2) receptor (MoAb BT 563). Nine of the 14 patients had also failed Xoma-Zyme-H65 as GVHD prophylaxis and/or treatment. Seven patients had received HLA-matched sibling donor bone marrow transplants, five had received HLA-matched transplants from unrelated volunteer donors, and two had received one-antigen mismatched transplants from unrelated volunteer donors. At the time of MoAb BT 563 therapy, the overall clinical grading of acute GVHD (Seattle grading system) was as follows: grade II--one patient, grade III--four patients, and grade IV--nine patients. MoAb BT 563 was administered as a short iv infusion of 5 mg daily for 10 doses, followed by 5 mg on alternate days for a further five doses. A complete response (CR) was observed in four patients (28%), and a partial response (PR) in four patients (28%). All four complete responders were treated within 28 days of first onset of grade > or = II acute GVHD. Four patients (three CR, one PR) remain alive. One complete responder subsequently died from chronic GVHD. MoAb BT 563 administration was well tolerated in all 14 patients; no significant toxicity was observed. We conclude that MoAb BT 563 directed against the IL-2 receptor on activated T lymphocytes may be useful in treating corticosteroid-resistant acute GVHD if given early, but that it is of limited value in attempting to rescue patients with far-advanced refractory acute GVHD.(ABSTRACT TRUNCATED AT 250 WORDS)

Regulation of tumor necrosis factor-alpha production and gene expression in monocytes

Tumor necrosis factor-alpha (TNF-alpha), produced predominantly by activated monocytes/macrophages, inhibits leukemic cell growth and may contribute to a graft-versus-leukemia effect after marrow transplantation. We examined the recombinant cytokines interferon (IFN)-alpha, IFN-gamma, granulocyte- macrophage colony-stimulating factor (GM-CSF), and macrophage colony-stimulating factor (M-CSF), alone or in combination, for their ability to induce monocytes from normal donors and patients after marrow grafting to express TNF-alpha mRNA and secrete TNF-alpha bioactivity. Monocytes were isolated from peripheral blood by Percoll separation of E-rosette-negative cells, and cultured with cytokines under non-adherent, endotoxin-free conditions. TNF-alpha transcripts were undetectable in freshly isolated monocytes from normal donors. Only the combination of IFN-gamma/GM-CSF was consistently capable of inducing substantial TNF-alpha mRNA transcript levels and protein secretion. Levels of TNF-alpha transcripts induced by IFN-gamma/GM-CSF were maintained for at least 36 h, in contrast to lipopolysaccharide (LPS) stimulation which caused TNF-alpha mRNA levels to peak after 2 h and decline rapidly thereafter. IFN-gamma/GM-CSF was also capable of inducing a prolonged (at least 48 h) secretion of TNF-alpha bioactivity. In contrast, greater than 80% of the total TNF-alpha bioactivity secreted by LPS-stimulated monocytes was secreted in the first 8 h. When monocytes were incubated with IFN-gamma alone ('priming'), washed and then exposed to GM-CSF, both TNF-alpha mRNA expression and TNF-alpha protein production occurred.(ABSTRACT TRUNCATED AT 250 WORDS)

Influence of post-methotrexate folinic acid rescue on regimen-related toxicity and graft-versus-host disease after allogeneic bone marrow transplantation

Thirty-two patients undergoing related-donor bone marrow transplantation (BMT) received cyclosporine (CSP) and methotrexate (MTX) with folinic acid rescue (FAR) as graft-versus-host disease (GVHD) prophylaxis. Fifty consecutive related-donor BMT patients given the CSP/MTX combination without FAR were utilized as historical controls. Patients receiving FAR experienced earlier engraftment, with absolute neutrophil count greater than 0.5 x 10(9)/l at a median of 17 days (vs 21 days in controls, p = 0.002). The day of last platelet transfusion was earlier in the FAR group (median of 14 days vs 17 days in controls, p = 0.01). Compared with the control group, patients receiving FAR had a lower incidence of grade II-IV stomatic (53% vs 78%, p = 0.04) and hepatic (25% vs 56%, p = 0.01) regimen-related toxicity. In the FAR group, 70% required total parenteral nutrition vs 92% of controls (p = 0.02). Broad-spectrum antibiotics were given to FAR patients for a median of 21 days (vs 23 days in controls, p = 0.09). The incidence of grade II-IV acute GVHD was similar in the FAR and control populations (45% and 35%, respectively, p = NS) as was the incidence of chronic GVHD (62% vs 55%, respectively, p = NS). Estimated event-free survival is 59% for FAR patients (median follow-up 64 weeks) and 58% for controls (median follow-up 109 weeks, p = NS). FAR reduces regimen-related toxicity in patients receiving CSP/MTX acute GVHD prophylaxis without significantly influencing GVHD incidence or event-free survival.

Treatment with recombinant interferon (alpha-2b) early after bone marrow transplantation in patients at high risk for relapse [corrected]

Relapse continues to be a problem after bone marrow transplantation (BMT) for hematologic malignancies, particularly in recipients of autologous or T-cell-depleted allogeneic grafts and in patients with advanced disease. Interferon (IFN) has shown antiproliferative activity in several malignant hematologic diseases and potentially may be of benefit when administered early after BMT when the number of residual cells is minimal. We tested in a phase I study the maximum tolerated daily dose of recombinant IFN alpha-2b in patients who had received a transplant for a disease at high risk for relapse (acute myeloid leukemia or non-Hodgkin's lymphoma beyond first remission, advanced myelodysplastic syndrome, acute lymphoblastic leukemia at any stage, chronic myeloid leukemia in accelerated or blast phase. Recombinant IFN alpha-2b was started at a dose of 0.5 x 10(6) IU/m2 and escalated by 0.5 x 10(6) IU/m2 in groups of three or four patients. The intention was to administer IFN as soon as stable engraftment after BMT was achieved (defined as an absolute neutrophil count of greater than 2.0 x 10(9)/L and platelet count greater than 100 x 10(9)/L for 5 consecutive days) and continued for 2 months. A total of 14 patients were enrolled after autologous (n = 3) or allogeneic (n = 11) BMT. Dose-limiting toxicity was myelosuppression. Significant (grade 2 to 4) neutropenia and thrombocytopenia led to discontinuation or dose reduction in five of eight patients receiving 1.5 x 10(6) or 2 x 10(6) IU/m2 IFN. Mild to moderate (grade 1 or 2) anorexia, weight loss, and fatigue occurred in the majority of patients independent of the IFN dose. De novo acute GVHD responsive to steroid treatment developed in 3 of 11 allograft recipients. Natural killer (NK) cell function was low before IFN treatment and was not improved with the cytokine. Conversely, interleukin-2-activated NK cells showed normal function even before starting IFN and no change was seen during IFN treatment. Clonogenic hematopoietic progenitor studies showed depression of all progenitor lines (colony-forming unit [CFU]-granulocyte, erythroid, monocyte, megakaryocyte, CFU granulocyte-macrophage, burst-forming unit-erythroid) by IFN at all dose levels except at 0.5 x 10(6) IU/m2. Considering this result and the incidence and severity of marrow depression seen at doses greater than 1.0 x 10(6) IU/m2, we would consider this the maximum dose safely tolerated if IFN alpha-2b is administered in this setting for a prolonged course on a daily basis.

Allogeneic bone marrow transplantation using unrelated donors: a pilot study of the Canadian Bone Marrow Transplant Group

Between February 1988 and January 1990, 35 patients underwent allogeneic bone marrow transplantation (BMT) from unrelated donors using measures routinely employed for matched related donors. Median patient age was 34 years (range 2-49). Thirty-two patients had hematologic malignancies, including chronic myelogenous leukemia (CML) in 16; three patients had severe aplastic anemia. Donor-patient pairs were matched at the HLA loci tested serologically (HLA-A, -B, -DR) in 29 cases; mixed leukocyte culture results were variable but often reactive. Five patients died prior to day +28 without evidence of myeloid engraftment, and one patient developed fatal graft failure several months after initial engraftment. Acute graft-versus-host disease (GVHD) occurred in 77% (95% confidence interval [CI] 60-90%) of all patients, and GVHD contributed to the death of 10 patients. Fatal regimen-related toxicity occurred in four patients and another died due to neurologic complications of a process that resembled the hemolytic-uremic syndrome. Two acute leukemia patients relapsed, and a CML patient was found to have a localized non-Hodgkin's lymphoma at necropsy. As of 1 June 1991, 14 patients are alive and in remission at a median follow-up of 1.9 years (range 1.5-3.3); all except one have normal performance scores. The 2-year actuarial event-free survival for all patients is 40% (95% CI 24-56%). Proportional hazards analysis revealed favorable significance for female patient sex, less advanced disease status and shorter interval from diagnosis to BMT. While unrelated-donor transplants need not necessarily duplicate the results of related-donor transplants to be of benefit, the event-free survival in this series was roughly similar to that expected in the related-donor situation, with the high transplant-related mortality somewhat offset by a low recurrence rate. Further studies using unrelated donors, employing new methods of preventing transplant-related complications, are indicated.

Neurologic complications in allogeneic bone marrow transplant patients receiving cyclosporin

Regimens using cyclosporin (CSP) and either methylprednisolone (MP) or methotrexate (MTX) have been useful in the prophylaxis of acute graft-versus-host disease (GVHD) after allogeneic bone marrow transplantation (BMT). However, CSP produces a number of side effects, including neurologic toxicity. A retrospective review of recipients of 239 BMTs given CSP-based prophylactic regimens revealed that 10 patients (4.2%, 95% confidence interval 0% to 10.4%) experienced a syndrome characterized by hypertension, severe visual disturbances, seizures and occipital lobe density changes on brain computed tomography (nine patients) or nuclear magnetic resonance imaging (one patient). Neurologic findings were reversible in all cases, usually after temporary discontinuation of CSP. Univariate analysis identified the following risk factors for neurotoxicity: use of unrelated or HLA-mismatched related donors, administration of etoposide (VP-16) or total body irradiation as part of conditioning, use of corticosteroids for prophylaxis or treatment of acute GVHD, or development of either acute GVHD or clinically significant microangiopathic hemolytic anemia (MAHA) post-BMT. In multivariate analysis, the most important predictors were the use of VP-16 (p = 0.008), the use of a continuous infusion CSP plus MP prophylactic regimen for GVHD (p = 0.003) and the development of MAHA after BMT (p less than 0.001). The strong association with MAHA suggests that endothelial damage is related to the development of this complication.

Involvement of fibronectin and its receptor in human lymphocyte proliferation

Adhesion between lymphocytes and antigen-presenting cells is necessary for the development of certain immune reactions. We have previously shown that fibronectin (FN) added to mixed lymphocyte cultures (MLC) can restore a decreased lymphocyte proliferation in immunocompromised individuals. Using highly purified cell populations from peripheral blood for depletion and adding back experiments we show here that exogenous FN enhanced proliferation only when allogeneic monocytes were co-cultured with responder lymphocytes. Although lymphocyte proliferation in MLC was augmented by FN, there was no preferential proliferation of any particular major lymphocyte subpopulation in cultures supplemented with FN as compared to control cultures lacking its addition. Antibody against the FN receptor (FN-R) of the beta 1 integrin family, as well as Arg-Gly-Asp containing peptide, could inhibit alloantigen-induced lymphocyte proliferation in a concentration-dependent manner. Anti-CD3-induced proliferation was inhibited by anti-FN-R antibody but not Arg-Gly-Asp peptide whereas no inhibition was seen with the phytohemagglutinin (PHA)-induced lymphocyte proliferation. This study presents further evidence that FN and its receptor (alpha 5 beta 1) are involved in the augmentation of T-cell responsiveness to proliferative stimuli.

Mesna versus hyperhydration for the prevention of cyclophosphamide-induced hemorrhagic cystitis in bone marrow transplantation

Hemorrhagic cystitis is a major complication of high-dose cyclophosphamide therapy used in preparation for allogeneic or autologous bone marrow transplantation. Although previous reports had suggested that the sulfhydryl-containing compound mesna might be superior to forced diuresis in preventing hemorrhagic cystitis, there were concerns about the effect of mesna on engraftment in these studies. To address these concerns, 100 patients were randomized to receive mesna or forced saline diuresis while undergoing bone marrow transplant conditioning with regimens that included high-dose cyclophosphamide. To try to minimize the likelihood of graft rejection, patients who were being transplanted with cyclophosphamide as a sole agent were excluded from the study. After randomization and administration of therapy, patients were monitored by microscopic and dip-stick urinalyses; they were also followed for effects of therapy on engraftment. The incidence of consistent or severe hematuria was 33% in the mesna arm and 20% in the hyperhydration arm (P = .31). Severe bleeding occurred in 12.5% of mesna patients and 7.5% of hyperhydration patients (P = .71). No unexpected toxicities were encountered, and engraftment times did not differ. Based on this randomized trial of 100 patients, we conclude that mesna and hyperhydration are equally effective in preventing cyclophosphamide-induced hemorrhagic cystitis in bone marrow transplantation patients.

Busulfan, cyclophosphamide, and melphalan conditioning for autologous bone marrow transplantation in hematologic malignancy

Sixteen patients with poor-prognosis acute myelogenous leukemia (AML), acute lymphoblastic leukemia (ALL), and non-Hodgkin's lymphoma (NHL) underwent conditioning with busulfan (16 mg/kg) and cyclophosphamide (120 mg/kg) (BUCY-2) plus melphalan (90 or 135 mg/m2) and autologous bone marrow transplantation (AuBMT) in a phase I study. At the melphalan dose of 90 mg/m2, grade greater than or equal to 3 regimen-related toxicity (RRT) was observed in five patients (31%; 95% confidence interval [CI], 11% to 59%), with hepatic (venoocclusive disease [VOD]) and urinary (hemorrhagic cystitis) RRT being the most frequent complications. Further escalation of the melphalan dose to 135 mg/m2 was deemed excessively toxic, as three of five patients had grade greater than or equal to 3 RRT. Following this experience, 21 patients with multiple myeloma (MM) and chronic myelogenous leukemia (CML) were treated with BUCY-2 plus melphalan 90 mg/m2 and AuBMT in separate studies. Three of these patients--all with extensively pretreated MM--had grade greater than or equal to 3 RRT (14%; 95% CI, 3% to 36%); no others had grade greater than or equal to 3 RRT. Therefore, a total of eight of the 37 patients (22%; 95% CI, 10% to 38%) who received BUCY-2 plus melphalan 90 mg/m2 conditioning developed grade greater than or equal to 3 RRT; three of these patients (8%; 95% CI, 3% to 25%) died of RRT. Although limited by the relatively small number of patients, our analysis of the patients receiving this regimen showed that the presence of parameters denoting the lymphoid diagnostic group (ie, ALL, NHL, and MM), more extensive pretreatment, and/or more advanced disease status were associated with a higher incidence of grade greater than or equal to 3 RRT. Response data on the AML, ALL, and NHL patients who received BUCY-2 plus melphalan 90 mg/m2 were analyzed: three patients (all with AML in first or second remission) are leukemia-free at 3.0, 2.8, and 1.4 years after AuBMT. The actuarial 2-year event-free survival in this group is 17% (95% CI, 5% to 54%). Response data on the MM and CML patients will be reported subsequently. BUCY-2 plus melphalan at a dose of 90 mg/m2 before AuBMT produces acceptable toxicity in patients who are not heavily pretreated. A full evaluation of the antineoplastic effects of this regimen requires further study.

Intensive chemotherapy with cyclophosphamide, carmustine, and etoposide followed by autologous bone marrow transplantation for relapsed Hodgkin's disease

Fifty-six consecutive patients with advanced Hodgkin's disease considered incurable with further conventional chemotherapy were entered into a protocol that included high-dose cyclophosphamide (7.2 g/m2), carmustine (BCNU; 0.6 g/m2), and etoposide (VP16-213; 2.4 g/m2) (CBV) followed by autologous bone marrow transplantation (BMT). Prior combination chemotherapy had failed in all the patients, and all but five had been previously treated with both mechlorethamine, vincristine, procarbazine, and prednisone (MOPP) and doxorubicin, bleomycin, and vinblastine with or without dacarbazine (ABV[D]). Thirty-four eligible patients received short-course conventional chemotherapy and/or involved-field radiotherapy before CBV. However, formal restaging was not performed after these conventional therapies; ie, the therapies were not used to select responding patients for transplantation, and all who received such therapy subsequently received CBV and autologous marrow grafts. Forty-four patients (80%; 95% confidence interval [CI], 69% to 91%) achieved a complete response after CBV and BMT. Performance status at protocol entry and the use of conventional cytoreduction therapy before CBV correlated with response. Median follow-up is now 3.5 years (range, 2.5 to 5.0 years). Kaplan-Meier estimates for overall and event-free survival 5 years after transplant are 53% (95% CI, 37% to 67%) and 47% (95% CI, 33% to 60%), respectively. In a univariate analysis, patients with a normal performance status and those without constitutional ("B") symptoms at protocol entry had an improved overall and event-free survival. In a multivariate analysis, only a normal performance status remained significant. Disease progression occurred in 17 patients at an actuarial rate of 39% (95% CI; 26% to 56%) and occurred at previous sites of active disease in all but one patient; our analysis did not identify prognostic factors for progression. Toxic deaths, caused by either neutropenic sepsis or interstitial pneumonitis (IP), occurred in 12 patients (21%; 95% CI, 10% to 32%). CBV with autologous marrow support can produce durable remissions in a substantial number of patients with Hodgkin's disease considered incurable with conventional measures. Regimen refinements may even further improve the therapeutic index of BMT in this malignancy.

Regulation of fibronectin receptor (alpha 5 beta 1) mRNA expression in human monocytes and monocyte-derived macrophages by activation/differentiation signals

Members of the beta 1 subfamily of integrins, a group of heterodimeric transmembrane adhesion receptors, mediate the attachment of monocytes and macrophages to cell matrix proteins such as fibronectin, collagen, and laminin. Such interactions are likely of considerable importance during inflammatory responses, when monocytes are recruited to, and retained in, extravascular sites. Because of the complexity of the interactions that befall monocytes during an inflammatory response, it seems likely that expression of adhesion receptors on monocytes would be precisely regulated. In the present study, we have examined the mRNA expression of alpha 5 and beta 1 subunits of the fibronectin receptor in purified human peripheral blood monocytes and monocyte-derived macrophages cultured in the absence or presence of various agents known to induce activation and/or differentiation. Incubation under nonadherent conditions for 6 h with interferon (IFN)-gamma or bacterial lipopolysaccharide (LPS) resulted in a decreased expression of both alpha 5 and beta 1 mRNAs in freshly isolated monocytes. In contrast, incubation with IFN-alpha did not result in a decreased expression of alpha 5 mRNA, although a moderate decrease in beta 1 mRNA was observed. Culture with granulocyte-macrophage colony-stimulating factor, macrophage colony-stimulating factor, phorbol myristic acetate, or plasma fibronectin (under nonadherent and adherent conditions) did not result in a change in levels of alpha 5 or beta 1 transcripts. In contrast to the results obtained with freshly isolated monocytes, incubation for 6 h with IFN-gamma or LPS did not alter the expression of alpha 5 or beta 1 mRNA in macrophages derived by culture of monocytes for 6 days in Teflon beakers. Our results indicate that IFN-gamma and LPS, both of which may be present in inflammatory sites, downregulate the mRNA expression of fibronectin receptor subunits in monocytes. Moreover, alpha 5 and beta 1 gene regulation by these agents is apparently dependent on the differentiation stage of the cells. This may provide a mechanism by which extravasating monocytes detach from extracellular matrix proteins, present in subendothelial basement membranes and deposited in sites of inflammation, in order to pursue other activities.

Immunotherapy after bone marrow transplantation

Residual disease after bone marrow transplantation (BMT) can either cause relapse or persist in a balanced state in which immune mechanisms keep control over malignant cell proliferation. After allogeneic BMT the latter mechanism [summarized as graft-versus-leukemia (GVL)] is probably supported by cellular (e.g. T lymphocytes, natural killer cells) and humoral (e.g. cytokines) effectors and often linked to clinical manifestations of GVHD. Preclinical and clinical studies are now emerging in which cytokines, such as interleukin-2 or interferons, are given after BMT to support cellular immune function particularly in situations in which GVL does not occur. We summarize here results from both pre-clinical and clinical studies that are relevant to the design of protocols seeking to improve elimination of residual malignant disease in BMT patients by modulation of the immune system.

Regimen-related toxicity of a busulfan-cyclophosphamide conditioning regimen in 70 patients undergoing allogeneic bone marrow transplantation

The regimen-related toxicity (RRT) of a busulfan (16 mg/kg) and cyclophosphamide (120 mg/kg) conditioning regimen (BuCy) was evaluated in 70 consecutive patients undergoing allogeneic bone marrow transplantation for hematologic malignancies. Patients were given toxicity gradings retrospectively in each of eight organ systems (cardiac, bladder, renal, pulmonary, hepatic, CNS, stomatic, and gastrointestinal) according to a recently developed RRT scale. A set of patient, disease, and treatment parameters (age, sex, diagnosis, Eastern Cooperative Oncology Group [ECOG] score, preconditioning liver function tests [LFT], prior chemotherapy exposure, disease status, graft-versus-host disease [GVHD] prophylaxis, antimicrobial agent use, hematologic recovery, and severity of acute GVHD) was statistically analyzed to determine significant predictors of RRT. The most common significant organ toxicities were stomatic (87% of patients; 63% grades II to IV) and hepatic (83% of patients; 44% grades II to IV). Renal and gastrointestinal toxicities were not uncommon (35% and 27%, respectively) but were rarely serious (9% and 1% grades II to IV, respectively). Twelve patients developed grade III toxicities of the following systems: hepatic (seven), pulmonary (two), bladder (two), and CNS (one). Females had more frequent stomatitis (P = .04) and hepatic RRT (P = .004). Patients receiving methotrexate in their GVHD prophylactic regimen experienced more grade II to IV stomatitis (P = .04) and hepatic RRT (P = .04). The use of amphotericin B (P = .01) or prolonged antibiotic courses (P = .04) was associated with more grades II to IV hepatic RRT. In a multivariate analysis, only amphotericin B administration predicted grades II to IV hepatic RRT (P = .01). The incidence of acute GVHD was 49%, with 31% having grades II to IV GVHD. The estimated 2-year event-free survival (EFS) for the entire study group was 44%. The estimated 2-year EFS was 63% for standard-risk patients (acute leukemia in first remission and chronic myelogenous leukemia [CML] in first stable phase) and 24% for all others (high-risk patients). High-risk patients were at increased risk of disease recurrence and RRT. BuCy is an efficacious bone marrow transplant conditioning regimen for standard-risk patients with leukemia but has significant associated hepatic RRT.

Fibronectin receptor subunit (alpha 5, alpha 4 and beta 1) mRNA and cell surface expression in human peripheral blood B lymphocytes

Members of the beta 1 family of heterodimeric adhesion molecules, e.g., the fibronectin receptors alpha 5 beta 1 and alpha 4 beta 1, mediate the binding of leukocytes to extracellular matrix proteins and may also support cell-cell interactions important for homing and localization of leukocytes at sites of immune and inflammatory reactions. In the present investigation, we have examined human peripheral blood B lymphocytes for mRNA and cell surface expression of fibronectin receptor subunits. B cells (CD 19-positive cells) expressed alpha 4 and beta 1, but not alpha 5, on their surface as determined by double immunofluorescence staining. Highly purified B cells, sorted on the basis of lymphocyte light scatter characteristics and the presence of surface IgM, expressed alpha 4, beta 1 and alpha 5 mRNAs. Expression of integrins, such as alpha 4 beta 1, on B lymphocytes may be important for cell-cell interactions that occur during immune responses.