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A R Zander

Publications and source records attributed to A R Zander.

At least 91 records · Page 5Linked to original sources
PubMed1999

Graft engineering of G-CSF-mobilized allogeneic leukapheresis products by counterflow centrifugal elutriation after CD34 column adsorption.

A major hindrance to the use of PBSC in allogeneic transplantation is the high rate of contamination with T lymphocytes, resulting in a considerable risk of GvHD. Natural killer (NK) cells are active against tumor cells but do not contribute to the development of GvHD. After adsorption of CD34+ cells of mobilized allogeneic leukapheresis products on a Ceprate column, we studied the separation of CD34 unadsorbed cells by counterflow centrifugal elutriation (CCE). Up to 1.0 x 10(10) cells were clearly separated into lymphocytes (fractions 110 and 140 ml/min), monocytes, and polymorphonuclear cells (fraction rotor off). Characterized by flow cytometry, T cells were distributed nearly equal to fractions 110 and 140. NK cells were concentrated 3.4-fold in fraction 140 as compared with the unseparated cells. The ratio of NK cells/T cells was improved by 33%. These results indicate that CCE is an effective method to enrich NK cells and to reduce T cells in stem cell separation products. Therefore, it is an option for adoptive therapy of cancer patients after transplantations (e.g., CML in relapse).

Antigens, CD34↗
PubMed1999

Expression of the adhesion molecules CD49d and CD49e on G-CSF-mobilized CD34+ cells of patients with solid tumors or non-Hodgkin's and Hodgkin's lymphoma and of healthy donors is inversely correlated with the amount of mobilized CD34+ cells.

The yield of CD34+ PBPC and colony-forming units-granulocyte-macrophage (CFU-GM) in leukapheresis products and the expression of the adhesion molecules CD11a, CD31, CD49d, CD49e, CD54, CD58, CD62L, c-kit (CD117), Thy-1 (CD90), CD33, CD38, and HLA-DR on CD34+ PBPC were analyzed in patients with cancer of the testis (n = 10), breast cancer (n = 10), Hodgkin's disease (n = 20), high-grade (n = 20) and low-grade (n = 20) non-Hodgkin's lymphoma, and healthy donors (n = 20) undergoing G-CSF (filgrastim)-stimulated PBPC mobilization. For each disease entity, G-CSF was administered in two different doses, 10 microg G-CSF/kg body weight (BW)/day s.c. vs. 24 microg G-CSF/kg BW s.c./day in steady-state condition. Data were compared for each dose group separately. Patients with cancer of the testis and breast cancer mobilized significantly more CD34+ cells than patients with high-grade and low-grade non-Hodgkin's lymphoma and Hodgkin's disease (p<0.05). Correspondingly, expression of CD49d on CD34+ PBPC was significantly lower in the same patients with cancer of the testis compared with high-grade and low-grade non-Hodgkin's lymphoma and Hodgkins' disease and in patients with breast cancer compared with high-grade and low-grade non-Hodgkin's lymphoma, Hodgkins's disease, and healthy donors. Similar results were obtained for CD49e. These data suggest that the expression of the adhesion molecules CD49d and CD49e on G-CSF-mobilized CD34+ cells of patients with solid tumors, non-Hodgkin's lymphoma, Hodgkin's disease, and healthy donors is inversely correlated with the amount of mobilized CD34+ cells.

Adolescent↗
PubMed1998

Difference between expression of adhesion molecules on CD34+ cells from bone marrow and G-CSF-stimulated peripheral blood.

Three-color immunofluorescence cytometry was used to quantify the expression of different adhesion molecules on CD34+ cells of steady-state bone marrow (BM) and peripheral blood stem cells (PBSC) after mobilizing with G-CSF (10 micrograms/kg/body weight) in nine cancer patients undergoing high-dose chemotherapy with subsequent autologous blood stem cell rescue. The expression rate of each adhesion molecule on CD34+ cells showed great inter-individual variations. High expression (> 50%) on CD34+ cells from PBSC and BM was found for CD58 (leukocyte function-associated antigen-3), CD31 (platelet-endothelial cell adhesion molecule-1), CD11a (leukocyte function-associated antigen-1) and CD49d (very late activation antigen-4); a moderate expression (20%-40%) was seen for CD49e (very late activation antigen-5), CD62L (leukocyte-endothelial cell adhesion molecule), CD54 (ICAM-1) and CD117 (c-kit). c-kit, CD58, CD62L and CD49d were less expressed on CD34+ cells of PBSC than of BM, the difference being statistically significant for CD49d (p < 0.05). CD49e and CD37 were expressed more in PBSC than BM without being statistically significant. The mean fluorescence intensity for all adhesion molecules on CD34+ cells did not differ significantly between PBSC and BM. The significantly lower expression of CD49d on G-CSF-mobilized PBSCs might suggest that downregulation of this molecule may be involved in the process of peripheral stem cell mobilization.

Adult↗
PubMed1998

Successful mobilization of peripheral blood stem cells in heavily pretreated myeloma patients with G-CSF alone.

We investigated the feasibility of mobilizing peripheral blood stem cells (PBSC) with G-CSF alone in 24 patients with multiple myeloma. The median age was 53 years (range 33-62). All patients had stage II/III disease and responded to standard first-line (n = 6) or salvage chemotherapy (n = 18). The median number of previous chemotherapy cycles was 7 (4-18) and the median number of prior melphalan-cycles was 6 (0-14). Nine (35%) patients had experienced prior radiation therapy. The patients received either 10 microg/kg G-CSF (n = 18) or 24 microg/kg G-CSF (n = 7, including one patient with previous 10 microg/kg G-CSF stimulation) daily s.c. for 5 or more consecutive days until completion of harvesting, starting apheresis on the fifth day. G-CSF treatment was well tolerated, with only slight bone pain in half of the patients (51%). After a median of three (range 1-7) apheresis procedures, medians of 3.8 (0.3-17) x 10(6) CD34+ cells/kg, 8.5 (4.5-24) x 10(8) MNC/kg, 2.9 (0.6-39.4) x 10(4) CFU-GM/kg, and 5.6 (0.9-49) x 10(4) BFU-E/kg were harvested. Three patients (12%) with extensive melphalan pretreatment failed the target collection of at least 2.0 x 10(6) CD34+ cell/kg. Pretreatment with six or more cycles of melphalan yielded a smaller number of CD34+ cells than pretreatment with fewer than six cycles (2.5 vs 5.3 x 10(6)/kg; p = 0.001). Nineteen patients underwent high-dose chemotherapy consisting of either total marrow irradiation (9 Gy)/busulfan (12 mg/kg) and cyclophosphamide (120 mg/kg) (n = 10), or busulfan (14 mg/kg)/cyclophosphamide (120 mg/kg) (n = 5), or tandem melphalan (200 mg/m2). The median time for granulocyte (> 1.0/nl) and platelet (> 50/nl) recovery was 10 and 14 days (ranges 7-12 and 8-40), respectively. G-CSF alone is a safe, alternative approach to mobilizing sufficient PBSC in patients with multiple myeloma and allows an exact prediction of harvest time. G-CSF-mobilized PBSCs ensure rapid engraftment after myeloablative therapy. Melphalan treatment should be avoided in patients who are candidates for high-dose chemotherapy.

Adult↗
PubMed1998

Specificity of reverse transcriptase polymerase chain reaction assays designed for the detection of circulating cancer cells is influenced by cytokines in vivo and in vitro.

Several reverse transcriptase polymerase chain reaction (RT-PCR) assays have been described for the detection of circulating tumour cells in blood and bone marrow. Target mRNA sequences for this purpose are the cytokeratins (CK) 19 and 20, the carcinoembryonic antigen (CEA), and the prostate-specific antigen messages. In this study, we investigated biological factors influencing the specificity of the CK19 and CEA RT-PCR assays. Bone marrow, granulocyte colony-stimulating factor (G-CSF)-mobilized blood stem cells and peripheral blood samples obtained from healthy volunteers (n = 15; CEA n = 7), from patients with epithelial (n = 29) and haematological (n = 23) cancer and from patients with chronic inflammatory diseases (n = 16) were examined. Neither CEA nor cytokeratin 19 messages could be amplified from bone marrow samples from healthy subjects and from patients with haematological malignancies. In contrast, specimens from patients with inflammatory diseases scored positive up to 60%. To investigate the influence of inflammation on target mRNA expression, haemopoietic cells were cultured with and without cytokine stimulation in vitro. CK19 messages could be easily detected in cultured marrow cells without further stimulation, CEA messages only after gamma-interferon (gamma-INF) stimulation. In contrast, G-CSF-mobilized peripheral blood stem cells were positive for CK19 messages only after stem cell factor (SCF) or interleukin stimulation. We conclude that transcription of so-called tissue-specific genes is inductible in haemopoietic tissues under certain conditions. These factors have to be considered in future applications of RT-PCR for the detection of minimal residual disease.

Abdominal Neoplasms↗
PubMed1998

Long-term disease-free survival of patients with advanced mantle-cell lymphoma following high-dose chemotherapy.

In advanced stage mantle cell lymphoma, conventional chemotherapy yields a complete remission rate below 40%, and the median survival rate is only about 3 years. Between 1991 and 1996 we treated nine such patients (six male; three female) with high-dose chemotherapy (six of these also with 12 Gy fractionated total body irradiation (TBI)) and peripheral stem cell support (n = 8) or allogeneic bone marrow transplantation (n = 1). The median age was 47 years (range, 28-61). At the time of high-dose chemotherapy, five patients were in first complete remission (CR), two in first partial remission (PR) and two in second remission (CR = 1; PR = 1). High-dose chemotherapy included TBI (12 Gy), etoposide and cyclophosphamide (patients 1-5), TBI and cyclophosphamide (patient 7), busulfan, etoposide and cyclophosphamide (patients 6 and 9), cyclophosphamide and busulfan (patient 8). The patterns of toxicity according to the Bearman score were usually mild (mucositis grade 2, n = 7; renal grade I, n = 2) with no therapy-related fatality. Only one patient developed hepatic toxicity grade III (veno-occlusive disease) but recovered completely. The median time to neutrophil engraftment was 10 days (range, 8-15). After high-dose chemotherapy all patients achieved complete remission. After a median follow-up of 22 months (range, 9.4-64) all patients remain in continuous complete remission. These encouraging results suggest that high-dose chemotherapy can be applied safely and leads to long-term disease-free survival in otherwise incurable disease.

Adult↗
PubMed1998

Soluble interleukin-2 receptor serum levels after allogeneic bone marrow transplantations as a marker for GVHD.

Acute GVHD (aGVHD) is one of the major problems after allogeneic BMT. The diagnosis of aGVHD is difficult to establish, relying mainly on clinical evaluations and symptoms of aGVHD, often resembling those of organ toxicity, infection or drug rash. In 21 patients after BMT several serum cytokine levels (soluble interleukin-2 receptor (sIL-2R), sTNF-R, SCF, IL-6, IL-8, G-SCF and ICAM-1) were determined in order to evaluate their value as an indicator for aGVHD. The maximum levels of sIL-2R (and none of the other evaluated cytokines) correlated significantly (r = 0.8, P = 0.008) with the severity of aGVHD. We also found a significant correlation between the day of engraftment (neutrophil count >0.5 x 10(9)/l) and the severity of aGVHD (r = 0.5, P = 0.03): engraftment was earlier in patients without aGVHD (median of day 11) than in those with aGVHD (median of day 18). No correlation between sIL-2R and fever or organ toxicity could be found. Our data suggest that the sIL-2R level might be an indicator for aGVHD, reflecting the severity of the disease. In patients with late engraftment the risk of aGVHD seems to be increased, therefore these patients especially should be monitored closely, possibly using sIL-2R levels.

Adolescent↗
PubMed1998

Purging and haemopoietic progenitor cell selection by CD34+ cell separation.

Tumour cell contamination of autologous peripheral blood stem cell samples (PBSC) and bone marrow (BM) is frequent. Enrichment of CD34+ stem cells is a promising approach to purging tumour cells from autografts without damaging progenitor cells. Breast cancer cells were seeded (10(-3)-10(-7)) into mononuclear cells from G-CSF-mobilised PBSC and BM harvests from patients without breast cancer. CD34+ cells were enriched from mixtures either by immunomagnetic separation (Isolex-50, and MiniMACS) or by biotin-streptavidin immunoaffinity columns (Ceprate-LC). CD34+ cell fractions were determined by FACS, cancer cells were detected immunocytochemically with an anti-pancytokeratin antibody. The CD34+ cells were enriched with a median purity of 92.2% (43.5-96.1) (n = 17) (Isolex-50), 96.5% (66.6-99.2) (n = 17) (MiniMACS) and 77.9% (31.4-93.6) (n = 15) (Ceprate-LC) from PBSC and BM harvests. The percentages of median recovery of CD34+ cells were 30.8% (18.6-71.8) (Isolex-50), 69.9% (39.1-100) (MiniMACS) and 42.9% (23.7-100) (Ceprate-LC). The median tumour cell reductions in log steps were 3.7 (2.9-4.3) (n = 13) (Isolex-50), 3.5 (2.6-4.3) (n = 13) (MiniMACS) and 1.5 (0.9-2.9) (n = 17) (Ceprate-LC). Results were compared statistically by univariate analysis. Purity was significantly (P < 0.05) better after MiniMACS selection. Recovery rates were significantly different between all devices tested. Tumour cell purging was superior after immunomagnetic separation (P < 0.001). Tumour cell purging is a main objective of CD34+ selection in the autologous setting. Our in vitro data clearly indicate that immunomagnetic separation is more efficient in the prevention of accidental reinfusion of contaminating tumour cells compared to immunoaffinity. However, it is not yet known if the same results can be obtained with fresh contaminating tumour cells.

Antigens, CD34↗
PubMed1998

Busulfan, cyclophosphamide and etoposide as high-dose conditioning therapy in patients with malignant lymphoma and prior dose-limiting radiation therapy.

Relapse after transplant for malignant lymphomas remains the main cause of treatment failure. Most conditioning regimens contain total body irradiation (TBI). We investigated the toxicity and efficacy of an intensified chemotherapy conditioning regimen without TBI in patients with relapsed or high-risk malignant lymphoma who had received prior radiation therapy and were therefore not eligible for TBI. Twenty patients with a median age of 38 (18-56) and relapsed or high-risk malignant non-Hodgkin's lymphoma (NHL, n = 16) or Hodgkin's disease (HD, n = 4) underwent high-dose chemotherapy consisting of busulfan (16 mg/kg), cyclophosphamide (120 mg/kg) and etoposide 30 mg/kg (n = 8) or 45 mg/kg (n = 12) followed by peripheral stem cell support (n = 14), autologous bone marrow (n = 3), allogeneic (n = 2) or syngeneic (n = 1) transplantation. All but two had chemosensitive disease before high-dose chemotherapy. The main toxicity -- according to the Bearman score -- was mucositis II in 18 (90%) patients; five patients (25%) suffered a grade I hepatic toxicity. GI toxicity I occurred in three (15%) and renal toxicity I in two patients (10%). Sixty percent of the patients developed transient dermatitis with erythema and three of them (15%) had skin desquamation; one patient experienced asymptomatic pancreatitis. Toxicity was slightly higher in patients treated with 45 mg/kg etoposide. One patient (5%) died of treatment-related venoocclusive disease. After a median follow-up of 50 months (24-84) the disease-free and overall survival were 50% and 55%. One of the nine relapsing patients developed secondary AML 18 months after transplant. High-dose busulfan, cyclophosphamide and etoposide is an effective regimen resulting in long-term disease-free survival in 50% of patients with relapsed malignant lymphoma and prior radiation therapy. The toxicity is moderate with a low treatment-related mortality (5%).

Adolescent↗
PubMed1998

Intensified conditioning regimen in bone marrow transplantation for Philadelphia chromosome-positive acute lymphoblastic leukemia.

We investigated an intensified conditioning regimen including fractionated total body irradiation (12 Gy), etoposide (30-45 mg/kg) and cyclophosphamide (120 mg/kg), followed by autologous (n = 5), allo-related (n = 13) or allo-unrelated (n = 6) bone marrow (n = 22) or peripheral stem cell (n = 2) transplantation in patients with Philadelphia chromosome-positive acute lymphoblastic leukemia. One patient received busulfan (16 mg/kg) instead of TBI. Nineteen patients were transplanted in 1CR, two in 2CR, one in 1PR and two in relapse. Major toxicity was mucositis grade II according to the Bearman scale in all patients. The treatment-related mortality was 25%, mainly due to infection or GVHD after allogeneic transplantation. After a median follow-up of 45 months (range 2-93), nine patients (37.5%) remain alive in CR. Nine patients (37.5%) relapsed and eight (33.3%) of these subsequently died. After autologous transplantation, four of five patients (80%) relapsed and died. Late relapse was seen after allogeneic, as well as autologous transplantation, at 33 and 59 months, respectively. The Kaplan-Meier estimate of leukemia-free survival for all patients is 38% at 3 years (95% CI: 18-58%) and 35% at 5 years (95% CI: 15-55%). For allogeneic transplants in first CR (n = 15) the estimate of disease-free survival was 46% at 3 years (95% CI: 19-73%) and 34% at 5 years (95% CI: 17-51%). Patients aged below 30 years had a better estimated overall survival at 3 years (61% vs 11%, P < 0.001). The bcr-abl fusion transcript (p210 vs p190 vs p210/190) did not affect disease-free or overall survival. In our experience, an intensified conditioning regimen seems to improve the results of bone marrow transplantation in patients with Ph+ acute lymphoblastic leukemia. However, the high relapse rate warrants novel approaches to enhance anti-leukemic efficacy.

Adolescent↗
PubMed1998

Highly-efficient gene transfer with retroviral vectors into human T lymphocytes on fibronectin.

Genetically modified lymphocytes have been successfully used for correction of ADA deficiency in children and in controlling graft-versus-host disease (GvHD) after allogeneic bone marrow transplantation. Low transduction efficiencies are, however, limiting for gene therapeutic strategies based on lymphocytes. In this study we compared protocols for highly efficient gene transfer into human T cells using retroviral vector-containing supernatant. We showed that infection of both human primary T cells and CD4+ Jurkat cells is most efficient on the matrix component fibronectin. Transduction was carried out with a retroviral vector encoding both the human intracytoplasmatically truncated low-affinity nerve growth factor receptor (deltaLNGFR) as a gene transfer marker and the Herpes simplex virus thymidine kinase for negative selection. Based on LNGFR expression genetically modified cells were enriched to near purity by magnetic cell sorting (MACS). Enriched cells could be shown to be highly sensitive to ganciclovir.

Anti-Allergic Agents↗
PubMed1998

Mobilizing peripheral blood stem cells with high-dose G-CSF alone is as effective as with Dexa-BEAM plus G-CSF in lymphoma patients.

We compared retrospectively the efficacy of granulocyte colony stimulating factor (G-CSF) alone with chemotherapy plus G-CSF in mobilizing CD34-positive cells in patients with malignant lymphoma. 35 patients underwent peripheral blood stem cell (PBSC) collection following mobilization either with 24 microg/kg G-CSF for 4 consecutive days (n = 18) or Dexa-BEAM chemotherapy plus 5 microg/kg G-CSF (n = 17). High-dose G-CSF was well tolerated with only slight bone pain and/or myalgia. The Dexa-BEAM therapy required hospitalization with a median duration of 21 d. The median number of apheresis procedures in both groups was two (range two to four), resulting in a median of 5.3 and 5.1 x 10(6) CD34+ cells/kg. No patients in the G-CSF group, but one in the Dexa-BEAM group, failed to reach the target of collecting >2.0 x 10(6) CD34+ cells/kg. The number of CFU-GM (10.4 v 6.0 x 10(5)/kg) and of BFU-E (10.6 v 4.5 x 10(5)/kg; P = 0.04) was higher in the G-CSF group than in the Dexa-BEAM group. A subset analysis of CD34+ cells was performed in 16 patients showing a higher mean of Thy-1 (CD90w) coexpression in the G-CSF than in the Dexa-BEAM group (4.8 v 1.8%, P = 0.12). Additionally the percentage of CD34+/CD38- cells was higher in the G-CSF group (10.66% v 8.8%). However, these differences were not statistically significant. The median time to leucocyte and platelet engraftment after high-dose chemotherapy was slightly shorter in the G-CSF than in the Dexa-BEAM group (9 v 10 and 12 v 13.5 d, respectively). These results demonstrate that high-dose G-CSF is as effective as Dexa-BEAM plus G-CSF in mobilizing peripheral blood stem cells and produces prompt engraftment. The major advantages of G-CSF mobilization were the safe outpatient self-application and the fixed-day apheresis.

Adolescent↗
PubMed1998

Treatment of mycotic infections after haemopoietic progenitor cell transplantation with liposomal amphotericin-B.

115 patients undergoing allogeneic or autologous bone marrow or peripheral blood stem cell transplantation were treated empirically or for documented fungal infection with liposomal amphotericin-B in doses up to 10mg/kg bodyweight for a duration up to 61 days. The therapy was excellent tolerated and clinical side effects occurred in only eight patients. The drug had to be withdrawn in one episode. A significant influence of liposomal amphotericin-B on laboratory parameters was not observed. Creatinine increased under therapy from a median base point of 1,0 (0,2-3,5) mg/dl to the upper normal value of 1,4 (0,4-4,2) mg/dl. Heavy increases of creatinine as well as of bilirubin, OT and PT were mostly associated with GvHD or regimen related toxicity. Considering the high-risk state of the patients the overall response rate was favourable with 62,9%. However, despite administration of liposomal amphotericin-B culture-proven mycoses were associated with a high morbidity (93,3%). Only one of fourteen patients was cured from Candida lambica septicaemia. We conclude that the antimycotic therapy with liposomal amphotericin-B has a low incidence of side effects. This should, considering the high mortality of fungal infections in BMT recipients, encourage investigators to perform dose escalating studies against the conventional formulation.

Adolescent↗
PubMed1997

Selective immunoaffinity-based enrichment of CD34+ cells transduced with retroviral vectors containing an intracytoplasmatically truncated version of the human low-affinity nerve growth factor receptor (deltaLNGFR) gene.

Human hematopoietic stem cells remain one of the most promising target cells for gene therapeutic approaches to treat malignant and nonmalignant diseases. To rapidly characterize transduced cells and to isolate these from residual nontransduced, but biologically equivalent, cells, we have used a Moloney murine leukemia virus (Mo-MuLV)-based retroviral vector containing the intracytoplasmatically truncated human low-affinity nerve growth factor receptor (deltaLNGFR) cDNA as a marker gene. Supernatant transduction of CD34+ cells (mean purity 97%) in fibronectin-coated tissue culture flasks resulted in 5.5-45% (mean 26%) transduced cells expressing deltaLNGFR (LNGFR+ cells). After transduction, more than 65% of the transduced cells remained CD34+. Compared with control (mock- and nontransduced) CD34+ cells, transduction did not decrease the cloning efficiency of CD34+ cells. Immunomagnetic selection of the transduced cells with a monoclonal anti-LNGFR antibody resulted in >90% LNGFR+ cells. Further phenotypic characterization of these highly enriched LNGFR+ cells indicated that the majority co-expressed the CD34 and CD38 antigens. These results show that transduced cells expressing an ectopic cell-surface protein can be rapidly and conveniently quantitated and characterized by fluorescence-activated cell sorting (FACS) analysis and fast and efficiently enriched by immunoadhesion using magnetic beads. The use of cell-surface reporters should facilitate optimization of methods of gene transfer into more primitive hematopoietic progenitors.

Animals↗