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M Sessarego

Publications and source records attributed to M Sessarego.

At least 73 records · Page 4Linked to original sources
PubMed1992

Characterization of EBV-positive lymphoblastoid cell lines obtained from HIV seropositive patients with or without lymphomas.

Epstein-Barr-virus- (EBV-) positive lymphoblastoid cell lines (LCLs) spontaneously arising in vitro were obtained from the peripheral blood of six HIV-seropositive patients and from the peripheral blood and the bone marrow of one patient (LAM) with AIDS and lymphoma. The LCLs from HIV-seropositive patients had phenotypic, cytogenetic, and biological characteristics indistinguishable from those of normal LCLs obtained by infecting B cells with EBV in vitro. The LCLs from LAM patient comprised composite cell populations. Cloning analysis and cell fractionation procedures showed that, beside normal EBV-infected cells, these lines contained a malignant subset population characterized by c-myc rearrangement, abnormal karyotype, and a surface phenotype similar to that of Burkitt's lymphoma cells. Analyses of Ig heavy chain and c-myc oncogene loci showed that these malignant cells were the progeny of a single precursor. Nevertheless, these cells had heterogeneous EBV-fused termini, a finding which indicates that EBV infection followed c-myc rearrangement.

Blotting, Southern↗
PubMed1992

Minimal residual disease status in transplanted chronic myelogenous leukemia patients: low incidence of polymerase chain reaction positive cases among 48 long disease-free subjects who received unmanipulated allogeneic bone marrow transplants.

Forty-eight long-term disease-free chronic myelogenous leukemia (CML) patients, who had received unmanipulated allogeneic bone marrow transplants (BMT) for eradication of the Philadelphia (Ph1)-positive clone were studied by polymerase chain reaction (PCR), using a very sensitive PCR procedure and very stringent criteria for preventing and revealing contamination. Nine patients (18%) were positive at the first PCR examination, but only one patient remained PCR positive four years after. However, a second PCR analysis performed on new bone marrow samples obtained at a median interval of 14 months (range 6-16) after the first specimen collection from six of nine originally positive cases, and from 16 of 39 originally negative cases, showed that only one of the six positive cases remained positive, whereas negativity was confirmed in all the originally negative patients. These data are evidence that the Ph1-positive clone is apparently completely eradicated in the majority of CML patients who survive disease-free long-term after an unmanipulated allogeneic BMT and that only sporadic cases remain PCR-positive four years post-BMT. The data also show that at least two sequential bone marrow samples for each patient must be analyzed before drawing conclusions regarding the stable persistence of BCR/ABL transcripts and the minimal residual disease status.

Adolescent↗
PubMed1992

Cytogenetic analysis of hemopoietic peripheral blood cells collected by leukapheresis after intensive chemotherapy in advanced phase Philadelphia-positive chronic myelogenous leukemia.

Peripheral hemopoietic blood cells previously collected by leukapheresis were reinfused in advanced phase Philadelphia (Ph)-positive chronic myelogenous leukemic patients to promote the recovery of bone marrow function after intensive radiochemotherapy. Cytogenetic analysis was performed on these cells, induced to proliferate and to be mobilized by a first administration of marrow toxic drugs and collected when the white blood cell count was very low. In five patients only Ph-negative apparently normal cells were found. In five cases different proportions of Ph+/Ph- cells were observed and in the remaining five cases only Ph+ cells were present. Chromosomal abnormalities other than Ph, not detected in the cytogenetic analysis performed on bone marrow cells before chemotherapy treatment, were found in five cases. These findings confirm that Ph- cells can persist in the marrow of Ph+ patients in the advanced phase of disease and indicate that a high percentage of leukemic cells retain karyotype evolution not detectable using standard drawing and culture techniques.

Antineoplastic Agents↗
PubMed1991

Emergence of a B-cell lymphoblastic lymphoma in a patient with B-cell chronic lymphocytic leukemia: evidence for the single-cell origin of the two tumors.

A patient is described who presented with a chronic lymphocytic leukemia (CLL) and later developed a lymphoblastic lymphoma. The cells from the CLL were typical mature B lymphocytes as could be assessed by morphologic, cytochemical, and surface marker analyses. The cells from the lymphoblastic lymphoma were immature B cells that expressed CD10, CD20, and HLA-DR markers, but not surface Ig or cytoplasmic mu chains, and were negative for terminal deoxynucleotidyl transferase (TdT). The cells of two continuous cell lines, obtained from the bone marrow and the peripheral blood of the patient, had the same phenotype as the lymphoblastic lymphoma cells, did not contain the Epstein-Barr virus genome, and displayed malignant features in vitro, including the capacity to form colonies in agar. The two cell lines also shared identical chromosomal abnormalities, a finding which suggests that they derived from the same malignant cell already present in vivo. Such chromosomal abnormalities were not seen in the karyotype of the peripheral blood cells at the onset of the disease. Analysis of the Ig heavy chain genes using a DJ-specific probe showed the very same monoclonal rearrangement in the cells from the B-CLL, the lymphoblastic lymphoma and the two cell lines, thus demonstrating their common clonal origin. By contrast, a monoclonal rearrangement of the lambda chain gene locus was found in the B-CLL cells only, a finding consistent with their exclusive capacity to express surface IgM lambda. This patient represents a rare case in whom a chronic lymphoproliferative disorder with mature malignant cells transforms into a lymphoblastic lymphoma characterized by cells frozen at a very early maturational stage. The possible mechanisms leading to such transformation within the same cell clone are discussed.

Adult↗
PubMed1991

Involvement of the short arm of the derivative chromosome 9 in Philadelphia-positive acute lymphoblastic leukemia.

Three Philadelphia chromosome (Ph)-positive acute lymphoblastic leukemia (ALL) patients showed rearrangement of the short arm of the chromosome 9 involved in Ph formation. At diagnosis, blast cells were morphologically L2 and phenotypically B-cell precursors, as shown by common ALL antigen (CALLA), B1, B4 and HLA-DR positivity. Cytogenetically, they had in common the presence of cells with normal karyotypes, the Ph, involvement of band 9p13----p21, and loss of region 9p13----9pter. In our experience, involvement of the p arm of the derivative chromosome 9 in Ph+ leukemias is a very rare event found in ALLs only.

Adult↗
PubMed1991

Karyotype evolution of Ph positive chronic myelogenous leukemia patients relapsed in advanced phases of the disease after allogeneic bone marrow transplantation.

Sixty-eight patients affected by Philadelphia chromosome (Ph) positive chronic myelogenous leukemia (CML) underwent allogeneic bone marrow transplantation (BMT) and were successfully studied from a cytogenetic point of view, before and after the BMT. Nineteen had evidence of cytogenetic and clinical relapse. Cytogenetic analyses of 14 patients who, after the relapse, showed progression to the accelerated or blastic phase of the disease, are presented. Five of these cases had only the Ph chromosome without karyotype evolution; in one case Ph duplication without other anomalies was detected, while in the remaining eight cases cytogenetic analysis showed apparently random clonal structural abnormalities (translocations, inversions, deletions, and marker formations). Therefore, the classical "non-random" abnormalities (+8, i(17q), +Ph, +19, +21) were not as common as in conventionally treated Ph+ CML. From our data, karyotype evolution during advanced phases in Ph+ CML patients after BMT differs from the evolution seen in conventionally treated patients, by the presence of numerous structural unusual abnormalities, possibly related to radiochemotherapy conditioning to BMT. Therefore, BMT treatment is not always able to eradicate the Ph+ clone but can reduce the incidence of the formation and/or expansion of Ph+ clones with additional non-random abnormalities.

Bone Marrow Transplantation↗
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↗
PubMed1991

An assessment of chimeric transcript detection in CML patients after bone marrow transplantation.

The Polymerase Chain Reaction (PCR) was used to evaluate minimal residual disease in 21 Ph+ CML patients at various intervals after allogeneic bone-marrow transplantation (ABMT) by amplification of bcr-abl cDNA. All patients were cytogenetically Ph- at the moment of molecular analysis. Of these 76% were PCR negative, 24% positive for bcr-abl transcripts. 100% of the Cyclosporine A/Methotrexate treated patients (7/7) were negative. Severe chronic GvHD was twice as frequent in PCR positive patients (60%) than in negative ones (31%). The only patient who relapsed during follow up was PCR positive. The two longest survivors were PCR negative. These data are still insufficient for assessing the predictive value of PCR analysis in CML. Patients. 25 patients with Ph+ CML at diagnosis were enrolled in this study. Two died soon after BMT because of infection for failure of engraftment/early relapse, two were Ph chromosome positive and PCR+, and were therefore dismissed from this study. All remaining 21 patients were cytogenetically Ph- at the time of molecular analysis and underwent ABMT from matched donors. All patients were conditioned with cyclophosphamide and TBI: 330 cGy the three days prior to transplantation (990 cGy total, treatment B), or 200 cGy two times daily for three days (1200 cGy total, treatment A). In 3 cases the marrow was treated for GvHD prophilaxis with Campath alone or Campath plus BT 5/9 monoclonal antibodies (1). All patients were treated with Cyclosporin A (CS) 5 mg/kg i.v. from the day prior to transplantation until 25-30 days after; 9 of these were treated with CS plus Methotrexate (MTX).

Biomarkers, Tumor↗
PubMed1990

Late-appearing Philadelphia chromosome in acute lymphoblastic leukemia.

We describe the cytogenetic analysis of a patient affected by a common acute lymphoblastic leukemia, L2 type. At diagnosis and first relapse, the karyotype was normal, whereas at the second relapse more than 60% of the examined cells showed a Philadelphia chromosome, without any change in the morphological and immunophenotypical picture. This case confirms the observation that leukemic cells are susceptible to developing a Ph, considered a primary chromosomal abnormality, during the course of the disease.

Chromosome Banding↗
PubMed1990

Secondary acute promyelocytic leukemia with t(8;21) and t(9;22) at onset and loss of the Philadelphia chromosome at relapse.

The translocation (8;21) is a typical marker of the M2 subtype of acute nonlymphocytic leukemia, whereas the Philadelphia (Ph) chromosome is predominantly associated with chronic myelogenous leukemia, and seldom with immature acute leukemias, either lymphoblastic or nonlymphoblastic. Furthermore, the association between t(8;21) and a Ph in the same cell is extremely rare. We present a case of secondary acute promyelocytic leukemia with a karyotype 46,XY,t(8;21), t(9;22) at onset. At relapse the patient lost the Ph, while maintaining the t(8;21). This apparently paradoxical pattern of cytogenetic features and evolution is discussed.

Bone Marrow↗
PubMed1990

Establishment of an EBV-positive lymphoblastoid cell line that grows as a lymphoma in nude mice and expresses membrane CD2 molecules.

We describe a human lymphoblastoid cell line (LCL), called ZS, that originated spontaneously from the cultures of gamma-irradiated (50 Gy) peripheral-blood mononuclear cells of a normal donor. When injected subcutaneously in sublethally irradiated, splenectomized and anti-asialo-GM1-treated nude mice, ZS cells invaded the lymph nodes, that appeared 10 to 50-fold enlarged in all of the mice tested. Furthermore, ZS cells expressed a typical T-cell surface structure, the CD2 molecule, detectable by a variety of different anti-CD2 monoclonal antibodies (MAbs). However, other T-cell markers were not found, with the possible exception of a truncated messenger of the beta chain of the T-cell receptor and ZS cells could be identified as B cells since they (i) expressed a battery of markers of the resting and activated B cells, (ii) displayed a monoclonal rearrangement of the IgH chain locus and (iii) synthesized IgM K molecules. The Epstein-Barr virus (EBV) genome was detected in ZS cells in approximately ten copies per cell by DNA hybridization techniques. Furthermore, the cells were positive for EBV nuclear antigens (EBNA). Western blotting analysis of EBV encoded antigens demonstrated clear differences with those present in the B 95.8 virus-producer cell line, indicating that ZS cells were not infected by EBV in vitro and that they already harbored the virus in vivo. ZS cells formed colonies in vitro with a high cloning efficiency and displayed chromosomal abnormalities in all of the mitoses (karyotype 47, xy, +13, -14, 8p+, 21p+, +m). In spite of these malignant features, ZS cells expressed the full range of EBV latent proteins as usually do "normal" LCSs and did not have any of the chromosomal abnormalities that juxtapose the c-myc oncogene to one of the genes coding for immunoglobulin molecules.

Animals↗
PubMed1990

Assessment of the potential malignancy of Epstein-Barr virus (EBV)-infected B cells in AIDS-related disorders.

Spontaneous lymphoblastoid cell lines (LCLs) were established from the peripheral blood of ten human immunodeficiency virus (HIV)-seropositive patients in order to investigate whether or not a progression of the cells toward a malignant state could be traced. The LCLs studied displayed no differences in their surface phenotype, karyotype, or tumorigenicity in nude mice when compared with a wide panel of control LCLs. However, four of the ten LCLs derived from HIV-seropositive patients formed colonies in agar with a cloning efficiency (0.1 to 0.9%) that was much lower than that of a control neoplastic B cell line (50%). Some sublines that were derived form the agar colonies expressed new activation markers (CD10 and Bac-1) but did not produce tumors in nude mice or display chromosomal abnormalities. These sublines might comprise cells that have progressed toward a more transformed state.

Animals↗
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↗
PubMed1990

Early and long term follow-up with minisatellite probes in bone marrow transplanted patients.

Twenty-five patients who received bone marrow transplantation (BMT) for chronic granulocytic leukemia (CGL), acute leukemia and severe aplastic anemia were studied before and after BMT in order to document and characterize the events following transplantation. DNA analysis was performed using minisatellite probes, which give rise to extremely polymorphic Southern blot band patterns specific to each individual and are regarded as "genetic fingerprint." Sensitivity studies using a mixture of donor and recipient cells could distinguish the presence of 1% of cells from one individual. Blood specimens were obtained from donor recipient before BMT and at days 10, 30, 90, and 270 after BMT. Karyotype analysis was also performed in CGL patients at the same time of DNA analysis. Engraftment was identified by DNA analysis as early as 10 days posttransplant and correlated with cytogenetic findings. This confirmed that a single hybridization filter is informative in 100% of patients and is easily applicable for early and long term studies of chimerism in BM transplanted patients.

Adolescent↗