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M R Raffo

Publications and source records attributed to M R Raffo.

At least 19 recordsLinked to original sources
PubMed1995

Influence of marrow CFU-GM content on engraftment and survival after allogeneic bone marrow transplantation.

The influence of the CFU-GM content of donor marrow on the outcome of allogeneic marrow transplantation (BMT) has been debated. We now report 38 patients (25 acute leukemias, 10 chronic myeloid leukemias, two myeloma; 24 in first CR/CP and 14 in more advanced phases of their disease) undergoing unmanipulated HLA-identical sibling BMT following conditioning with cyclophosphamide and total body irradiation (TBI). The median number of nucleated cells infused was 4.3 x 10(8)/kg (range 1.5-8.4); median CFU-GM numbers were 2.4 x 10(4)/kg (range 0.1-46). End-points of the study were (1) speed of neutrophil and platelet engraftment; (2) quality of engraftment beyond day +50 after BMT; and (3) transplant-related mortality in patients stratified according to whether they had received less than (n = 18) or more than (n = 20) 2.4 x 10(4)/kg CFU-GM. These two groups were comparable for diagnosis, disease status, donor sex, donor age, recipient sex, recipient age, CVHD prophylaxis, number of cells infused and CMV serology. Neutrophil counts were comparable at all time intervals. There was also no difference in platelet counts on days +7 to +50. However, patients who had received higher CFU-GM numbers had significantly higher platelet counts on day +80 (149 vs. 75 x 10(9)/L; P = 0.002), day +100 (153 vs. 77 x 10(9)/L; P = 0.0009) and day +150 (179 vs. 95 x 10(9)/L; P = 0.01). The 2-year actuarial transplant-related mortality was 5% vs. 53% (P = 0.007) in patients receiving high or low numbers of CFU-GM.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

In vitro effect of stem cell factor on colony growth from acquired severe aplastic anemia.

In this study we review our present understanding of the effect of stem cell factor (SCF) on the in vitro growth of hemopoietic progenitors from patients with acquired severe aplastic anemia (SAA). We have run three separate sets of experiments. First, we have tested the expression of receptor mRNAs for granulocyte-macrophage colony stimulating factor/interleukin 3 (GM-CSF/IL-3) and for c-kit protein on bone marrow (BM) cells from SAA patients. Molecular analysis revealed the presence of normal transcripts for alpha and beta chains of GM-CSF/IL-3 receptor and for c-kit protein by Northern blot analysis. Second, we have tested the in vitro response to SCF of BM cells derived from 11 SAA patients: SCF induced a significant enhancement of erythroid burst forming unit (BFU-E) growth (8 to 29, p = 0.01) and allowed the formation of granulocyte/erythroid/macrophage/megakaryocyte (GEMM) colonies which were not scored in baseline culture conditions (0 to 8, p = 0.01). Granulocyte-macrophage colony forming unit (CFU-GM) growth was also enhanced (4 to 20, p = 0.3). This was true for patients both at diagnosis and after antilymphocyte globulin (ALG) treatment. We concluded that SCF can promote the in vitro growth of hemopoietic progenitors in patients with acquired SAA. Third, we have tested the response to SCF of peripheral blood (PB) hemopoietic progenitors collected from patients receiving in vivo long-term treatment with granulocyte CSF (G-CSF). When PB cells were plated directly in the presence of GM-CSF there was no colony formation.(ABSTRACT TRUNCATED AT 250 WORDS)

Anemia, Aplastic↗
PubMed1993

Selective overshoot of Ph-negative blood hemopoietic cells after intensive idarubicin-containing regimen and their repopulating capacity after reinfusion.

Twenty-seven patients with chronic myelogenous leukemia (CML)--17 in the chronic phase and 10 in the accelerated phase--were treated with an intensive chemotherapy regimen consisting of idarubicin, arabinosylcytosine, and etoposide. All patients were ineligible for bone marrow transplantation (BMT) and showed little or no cytogenetic response to interferon alpha (IFN-alpha). Blood hemopoietic cells (BHC) were collected by leukapheresis in all patients during early recovery from chemotherapy-induced aplasia. In 13/27 patients (48%), all metaphases were Ph-negative (Ph-); in another five patients, the percentage of Ph-positive (Ph+) metaphases decreased to less than 50%. Complete Ph+ disappearance was found in 66% of the patients treated within two years of diagnosis and in only 30% of those treated later. The collected Ph- cells have been used as autotransplants in nine patients: seven have shown sustained engraftment, and five are alive and well, with Ph- at 3+, 4+, 7+, 11+, and 19+ months after transplant. It is remarkable that one patient, now Ph- at 19 months after transplant, is also PCR negative. These results suggest that it is possible to collect Ph- hemopoietic cells even years after diagnosis and to perform autologous transplants with these cells.

Adult↗
PubMed1993

Mobilization of cytogenetically 'normal' blood progenitors cells by intensive conventional chemotherapy for chronic myeloid and acute lymphoblastic leukemia.

Various lines of evidence suggest that substantial numbers of very primitive normal hematopoietic cells persist in the marrow of most patients with CML, despite the presence of an expanded Philadelphia-Chromosome (Ph) positive population, and that normal clones might, in certain circumstances, have a proliferative advantage over leukemic populations. We have recently demonstrated in 5/8 CML patients with blastic phase (BP) that the blood progenitor cells/(BPC) harvested during early recovery from marrow aplasia were Ph-negative on cytogenetic analysis, suggesting that leukapheresis may provide a useful source of 'normal' progenitors for subsequent reinfusions. We report here an update on 40 patients with Ph + CML and 9 patients with ALL in first or subsequent relapses with associated cytogenetic translocations including t(8;14) t(4;8) t(4;11) and t(9;22). All these patients received intensive conventional chemotherapy and during early recovery from marrow aplasia, when the WBC reached 0.5-2.0 x 10(9)/L, BPC were collected by 4-8 leukapheresis and tested for the persistence of the marker translocations and, when possible, for the presence of the hybrid bcr/abl transcripts by polymerase chain reaction (PCR). In seven out of 10 patients with chronic phase CML, BPC were Ph-negative and in 5 PCR negative. In both accelerated phase patients, BPC were Ph-negative but PCR-positive and in eight out of 28 blastic CML patients, BPC were Ph-negative and in two cases also PCR-negative. Six out of 9 ALL patients, lost the cytogenic translocations. After complete recovery, 16 patients were subsequently given high-dose therapy followed by reinfusion of 'normal' BPC.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

Collection of 'normal' blood repopulating cells during early hemopoietic recovery after intensive conventional chemotherapy in chronic myelogenous leukemia.

Twenty-five patients with CML (chronic phase (CP): 15 patients; accelerated phase (AP): 10 patients) at a median of 40 months after diagnosis and ineligible for allogeneic BMT, received an intensive chemotherapy regimen consisting of idarubicin, intermediate-dose ara-C and etoposide (ICE protocol). All patients had previously received alpha-interferon and only two patients had had partial cytogenetic response. During recovery from chemotherapy-induced aplasia, blood progenitors cells (BPC) were harvested by leukapheresis. All metaphases were found to be Ph-negative in the collection of 12 of 25 (48%) patients (CP: 9 of 15 (60%), AP: 3 of 10 (30%)) and a decrease of < 50% Ph-positive metaphases was seen in an additional five (CP: 4 patients; AP: 1 patient). The percentage of complete Ph-disappearance was 66% in patients receiving this procedure within the first 2 years of diagnosis and 30% in those treated after the second year of diagnosis. So far, the Ph-negative collections have been used in 9 patients (CP: 8 patients; AP: 1 patient) as autograft after conditioning with total body irradiation/etoposide/CY. Seven of 9 patients engrafted and 5 are alive and well, Ph-negative at 2+, 3+, 6+, 10+ and 18+ months.

Adult↗
PubMed1992

Intensive conventional chemotherapy can lead to a precocious overshoot of cytogenetically normal blood stem cells (BSC) in chronic myeloid leukemia and acute lymphoblastic leukemia.

Forty patients with Ph-positive blastic phase (BP) (28 patients) or chronic phase (CP)-CML (3 patients) and relapsed adult acute lymphoblastic leukemia (ALL) (9 patients) with cytogenetical translocations [t(8;14):2 patients; t(4;8):2 patients; t(4;11):3 patients; t(9;22):2 patients], received an intensive conventional chemotherapy. During early recovery from marrow aplasia, when WBC reached 0.3-1.5 x 10--9/L, peripheral blood stem cells (BSC) were collected by 4-8 leukapheresis consecutively. BSC collected from the 2/3 patients with CP-CML resulted Ph-negative and PCR negative. In 8 out of 26 BP-CML patients, BSC resulted Ph-negative and in two cases PCR negative. Of the nine ALL patients, 6 patients lost the cytogenetic translocations, one patient died during aplasia, two patients did not have cytogenetic modifications and died in few weeks of leukemia and one patient out of six responding patients relapsed before transplant. After complete recovery, 15 patients (BP-CML:8 patients; CP-CML:2 patients; ALL:5 patients) were subsequently given high-dose therapy (VP-16 +/- Cy+TBI in single dose) followed by reinfusion of "normal" BSC. Both the patients in CP-CML and 5/5 patients with ALL maintain clinical and cytogenetic remission; all the patients transplanted in BP-CML relapsed 5-18 months post-transplant. It is concluded that intensive conventional chemotherapy employed in CML and ALL can lead to a precocious overshoot of cytogenetically normal BSC.

Adolescent↗
PubMed1991

Therapy of acute phase chronic myelogenous leukemia with intensive chemotherapy, blood cell autotransplant and cyclosporine A.

The expansion of the Philadelphia (Ph) chromosome positive clone in chronic myeloid leukemia (CML) may depend on its capacity to suppress the proliferation of Ph-negative stem cells, but this proliferative advantage might, in certain circumstances, be reversible. Various lines of evidence suggest that Ph-negative cells, albeit in a suppressed state, must still be present. As recently suggested, the expansion of 'putative' normal Ph-negative hemopoietic stem cells might have, in certain circumstances, a proliferative advantage over the Ph clone in CML. This suggests that the treatment of CML with intensive chemotherapy might allow the collection of Ph-negative hemopoietic cells in the early phase of recovery. Eight patients with acute phase chronic myelogenous leukemia (AP-CML) were treated with idarubicin, intermediate dose cytarabine and etoposide. During recovery from bone marrow aplasia, when the white blood cell count reached 0.3-1 x 10(-9), blood cells were collected with 2-5 (median 3) consecutive leukapheresis. In 5/8 patients, these peripheral cells were Ph-negative at the cytogenetic analysis. Moreover, in one case the polymerase chain reaction analysis performed to detect the presence of minimal residual disease in the cells collected by leukapheresis was negative, further confirming that this approach may induce a very high degree of suppression of the Ph-positive clones. After complete recovery, these five patients were subsequently treated with high-dose etoposide, cyclophosphamide and total body radiation (10 Gy, single dose) followed by reinfusion of Ph-negative peripheral blood stem cells. All these patients received cyclosporine A post-autotransplant in an attempt to induce acute graft-versus-host-disease. Three of 5 patients remain in clinical and cytogenetic remission 5-15 months post-transplant. It is concluded that Ph-negative peripheral blood stem cells can be recovered from patients with AP-CML and used successfully to restore Ph-negative hemopoiesis after high dose therapy.

Adult↗
PubMed1990

Clinical use of GM-CSF in autologous bone marrow transplantation.

Over the last decade, the key role of specific glycoproteins (hematopoietic growth factors) in the proliferation and maturation of hematopoietic cells (in conjunction with some of their particular functional activities) has been demonstrated through in vitro and in vivo studies. These glycoproteins have been evaluated for their potential application in reducing the duration of myelosuppression following conventional chemotherapy and autologous bone marrow transplantation. Preliminary results using granulocyte-macrophage colony-stimulating factor to restore neutrophil competence seem to be encouraging.

Agranulocytosis↗
PubMed1990

Mixed chimerism after allogeneic marrow transplantation for leukaemia: correlation with dose of total body irradiation and graft-versus-host disease.

Fifty-four patients allografted for leukaemia were evaluated at various intervals after bone marrow transplantation for the presence of host haemopoiesis using red blood cell and cytogenetic markers. Out of 40 patients in remission, 10 showed functional host and donor haemopoiesis (mixed chimerism), whereas in the other 30 (complete chimerism) host haemopoiesis was never detected. Seven of the 14 evaluable patients who relapsed showed the reappearance of host haemopoiesis at the time of relapse. Analysis of the dose of total body irradiation (TBI) indicated that patients who achieved mixed chimerism, whether or not they relapsed, had received significantly lower doses than those with complete chimerism. However, some patients with complete chimerism had received a TBI dose equivalent to the dose received by those with mixed chimerism, suggesting that the TBI dose is not the only factor determining the reappearance of host haemopoiesis. The data on chimerism and relapse suggest that there is heterogeneity in radiosensitivity between normal marrow cells and leukaemic cells, and also within the different types of leukaemia. The incidence/severity of acute and chronic graft-versus-host-disease (GVHD) was significantly higher in patients with complete chimerism than in mixed chimeras, suggesting that mixed chimerism may play a role in the development of tolerance. Alternatively the absence of GVHD (i.e. tolerance) may be responsible for the persistence of host haemopoietic cells.

Bone Marrow Transplantation↗
PubMed1986

Competitive survival/proliferation of normal and Ph1-positive haemopoietic cells.

Bone marrow (BM) cells from 10 patients with Ph1-positive chronic granulocytic leukaemia (CGL) were placed in long-term cultures in the presence of fetal calf serum (FCS) and horse serum (HoS), or in the presence of human AB serum. The long-term cultures were started with three different cell combinations: (1) CGL BM cells (four cases), (2) CGL BM cells + normal BM cells (1:1 ratio) from an HLA identical sex-matched sibling (five cases), (3) CGL BM cells + normal BM cells (1:1 ratio) from an HLA identical sex mismatched sibling (five cases). Cytogenetic studies were performed at weeks 0, 3, 4 and 5 of culture. The results of this study can be summarized as follows: (a) Ph1-positive cells could be detected at any time of culture in all three of the described cell combinations; (b) a population of Ph1-negative cells of patient origin could be detected after 3-5 weeks of culture; (c) there was a trend for a better survival of Ph1-negative cells in cultures supplemented with FCS + HoS and, conversely, of Ph1-positive cells in cultures containing human serum. These results warrant further studies on the possibility of manipulating survival and proliferation of normal and leukaemic cells by varying the culture conditions.

Bone Marrow↗
PubMed1985

Cyclosporin A in marrow transplantation for leukemia and aplastic anemia.

A total of 29 consecutive patients with leukemia or aplastic anemia who received an HLA-identical marrow graft were given cyclosporin A (CyA) to prevent graft-versus-host disease (GvHD). These patients were compared with an historic group of 25 similar patients with leukemia or AA given methotrexate (MTX) for GvHD prophylaxis at this institution. Engraftment was faster in patients given CyA when compared with MTX patients, with less days of granulocytopenia (P = 0.04), a shorter interval before reaching a platelet count of 70 X 10(9)/l (P = 0.04), fewer major infections (P = 0.01), and fewer days on intravenous antibiotics (P = 0.02). There were no graft failures in CyA patients compared with four of 25 in MTX patients (P = 0.01). Early mortality was lower in CyA patients but not significantly (P = 0.06). The incidence of pulmonary complications was comparable, five of 29 and seven of 25 in CyA and MTX patients, respectively, but the clinical features of such complications differed. Interstitial pneumonia developing after day 30 was seen in MTX patients, whereas an acute respiratory distress syndrome developing between day +8 and day +18 was seen in CyA patients. Acute GvHD was less severe in CyA patients (P = 0.04), but chronic GvHD was comparable (P = 0.3). The actual one-year survival is currently 72% and 52% in CyA and MTX patients, respectively (P = 0.1). Although our initial experience with CyA is encouraging with regard to engraftment and acute GvHD, optimization of CyA protocols will probably be needed for it to be proven as having a definite advantage over MTX.

Adolescent↗
PubMed1984

Cyclosporin A serum and blood levels in marrow graft recipients: correlation with administered dose, serum creatinine and graft-versus-host disease.

23 patients undergoing marrow transplantation for leukemia or aplastic anemia were given cyclosporin A (CyA) for graft-versus-host disease (GvHD) prophylaxis. A radioimmunoassay was used to monitor CyA serum levels in 13 patients and whole blood levels in 10. Serum creatinine levels were recorded daily until day 30 and then weekly. The severity of acute GvHD was recorded daily for a total of 1,738 patient days. CyA dose was then correlated with CyA serum or blood levels, serum creatinine levels and severity of acute GvHD. The daily dose of administered CyA correlated with serum CyA levels (p = 0.001) but not with whole-blood CyA levels. The cumulative CyA dose correlated with serum creatinine. There was an inverse correlation between the daily CyA dose and the severity of acute GvHD (p = 0.05). On the other hand the total amount of CyA given within 10 days after bone marrow transplantation had no influence on the severity of acute GvHD developing after day 10. Serum and whole-blood levels did not correlate with severity of GvHD nor with creatinine levels. The results of this study point out the nephrotoxicity of CyA, and a low GvHD score with high doses of administered CyA, at least on a daily basis. Serum but not blood levels reflect the dose of CyA given, but are not correlated with nephrotoxicity or GvHD.

Bone Marrow Transplantation↗
PubMed1983

Generation of CFU-c suppressor T cells. VI. Effect of cyclosporin A.

CFU-c suppressor T cells were generated in vitro by culturing overnight peripheral blood T cells from healthy donors with pokeweed mitogen (PWM), or T cells from patients with severe aplastic anemia (SAA) in remission, with culture medium (RPMI). The supernatants were removed the next morning, the cells harvested and washed, and both tested for CFU-c suppression on normal marrow cells. Cyclosporin A (CyA) was added to this system to test whether it could abrogate or prevent the generation of suppressor cells. CyA was incubated with T cells, at a concentration of 0.1 microgram/ml, for 30 min at 37 degrees C and then washed away, in two different assays: (a) before T cells were incubated overnight in culture medium with or without PWM, or (b) after T cells had been kept overnight in culture. The results of this study indicate that CyA can prevent the generation of CFU-c suppressor T cells if preincubated with both normal or SAA T cells prior to in vitro priming, whereas it cannot abrogate the suppressor activity of primed T cells.

Anemia, Aplastic↗
PubMed1982

Generation of CFU-C suppressor T cells in vitro. V. A multistep process.

Different cell fractions obtained from five patients with immune severe aplastic anaemia (SAA) in complete autologous haematologic reconstitution were tested for CFT-c suppression. Bone marrow mononuclear cells (BMMC), but not peripheral blood mononuclear cells (PBMC), showed definite CFU-c inhibitory activity. On the contrary, both peripheral blood and marrow E rosetting cells (E+) suppressed CFU-c growth. The suppressor activity of PBE+ cells could not be rescued by adding back PBE- cells and/or PB adherent cells (AC). In addition, unfractionated PBMC exposed to sheep red blood cells (SRBC) suppressed CFU-c growth. PBMC from normal donors exposed to SRBC had no suppressor activity. This study suggests that CFU-c suppressor T cells in the peripheral blood of SAA patients are in different activation state as compared to BM cells from the same patients, and also differ from normal PB cells. The identification of T cells with different requirements for in vitro activation in order to exhibit a suppressor activity, suggests that generation of suppressor cells is a multistep process, and this may have practical implications for in vitro assays designed to test for immune suppression of haematopoiesis.

Anemia, Aplastic↗