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Donor Chimerism (donor + chimerism)
Kinds of Donor Chimerism Selected AbstractsFISH detection of chimerism in pediatric hematopoietic stem cell transplantationINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 3 2007F. AYDIN Summary Allogeneic hematopoietic stem cell transplantation (HSCT) is a well-established curative therapy for various malignant and non-malignant diseases. Successful outcome after allogeneic HSCT has been associated with donor chimerism (DC). However, the detection of residual host cells or mixed hemopoietic chimerism (MC) has indicated that donor chimerism is not obligatory following HSCT. More recently, fluorescence in situ hybridization (FISH) analysis has been applied to engraftment studies for the identification of polymorphic or sex chromosomes. In this study, chimerism status was evaluated in 48 sex-mismatched HSCT pediatric patients (17 women/31 men, mean age: 9.02 ± 3.95 years, range: 2,19) by FISH and the effect of DC or MC on outcome and long-term disease-free survival was documented. The stem cell source was bone marrow in all cases. All of the donors were human leucocyte antigen-identical siblings. FISH was performed on 156 specimens between days +13 and +1878. Donor chimerism was found in 47.9% (23/48) and MC was found in 52.1% (25/48) of the patients. Fifteen of 48 (31.25%) patients died, of whom 12 (80%) were MC and three patients (20%) were DC. The difference in chimerism status (MC or DC) was statistically significant between those patients who died and those still alive (,2 = 6.813; P = 0.009). [source] Kinetics of stem cell engraftment and clearance of leukaemia cells after allogeneic stem cell transplantation with reduced intensity conditioning in chronic myeloid leukaemiaEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 1 2002Karl-Anton Kreuzer Abstract: It is hypothesised that an effective graft-vs.-leukaemia reaction contributes substantially to the therapeutic effect of reduced intensity conditioning stem cell transplantation in chronic myeloid leukaemia. However, kinetic data on eradication of leukaemia cells and stem cell engraftement which could support this assumption are lacking . Thus, we investigated bcr/abl fusion transcripts and haematopoietic chimerism in 14 patients undergoing such a transplantation protocol. Ten of them obtained a complete molecular remission, and two patients achieved haematologic remissions but remained bcr/abl positive. Weekly determinations of bcr/abl transcript numbers by qualitative and quantitative polymerase chain reaction and donor chimerism revealed that 10 responders cleared bcr/abl positive cells from the peripheral blood within a median of 9 wk (range 3,22 wk). The close relation (P = 0.0075) between the firstoccurrence of graft-vs.-host disease and the complete clearance ofbcr/abl positive blood cells argues in favour of an effective graft-vs.-leukaemia reaction. [source] FISH detection of chimerism in pediatric hematopoietic stem cell transplantationINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 3 2007F. AYDIN Summary Allogeneic hematopoietic stem cell transplantation (HSCT) is a well-established curative therapy for various malignant and non-malignant diseases. Successful outcome after allogeneic HSCT has been associated with donor chimerism (DC). However, the detection of residual host cells or mixed hemopoietic chimerism (MC) has indicated that donor chimerism is not obligatory following HSCT. More recently, fluorescence in situ hybridization (FISH) analysis has been applied to engraftment studies for the identification of polymorphic or sex chromosomes. In this study, chimerism status was evaluated in 48 sex-mismatched HSCT pediatric patients (17 women/31 men, mean age: 9.02 ± 3.95 years, range: 2,19) by FISH and the effect of DC or MC on outcome and long-term disease-free survival was documented. The stem cell source was bone marrow in all cases. All of the donors were human leucocyte antigen-identical siblings. FISH was performed on 156 specimens between days +13 and +1878. Donor chimerism was found in 47.9% (23/48) and MC was found in 52.1% (25/48) of the patients. Fifteen of 48 (31.25%) patients died, of whom 12 (80%) were MC and three patients (20%) were DC. The difference in chimerism status (MC or DC) was statistically significant between those patients who died and those still alive (,2 = 6.813; P = 0.009). [source] Analysis of chimerism during the early period after allogeneic peripheral stem cell transplantationINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 6 2001B. Gleissner As there are few reports on early evaluation of chimerism, we assessed fluorescence short tandem repeats (STR) by polymerase chain reaction (PCR) assays to analyse donor and recipient characteristics at early time points after peripheral stem cell transplantation (PBSCT). Peripheral blood of 13 patients was analysed in 1- to 2-day intervals starting from the day of PBSCT. Donor and recipient allelic patterns were determined by a commercially available multiplex STR assay that simultaneously evaluates four or five gene loci. Mixed chimerism appeared in all patients during days 1,9 after transplantation and preceded haematologic engraftment for 3,12 days. Even patients without myeloablative conditioning therapy (n=4) revealed donor allelic patterns within 1,5 days. Nine patients changed during the following days to a complete donor allelic pattern and had an uncomplicated post-transplant disease course. Four patients did not consistently retain complete donor chimerism; two of them relapsed within the next 3 months, one died from septicemia within 7 days, and the fourth, transplanted for aplastic anaemia, is still in complete remission. Overall, STR analysis using a simple and comparatively cheap multiplex system permits the detection of chimerism very early after transplantation and may provide relevant information that correlates with the clinical follow-up. [source] Unrelated cord blood transplantation in children with severe congenital neutropeniaPEDIATRIC TRANSPLANTATION, Issue 6 2009M. Akif Yesilipek Abstract:, SCN is an inherited hematological disorder with severe neutropenia and recurrent infections. Although there are some reports that recombinant rhG-CSF improves clinical outcome, allogeneic HSCT appears to be the only curative treatment for these patients. We report here two children with SCN successfully treated by CBT from unrelated donors. They were refractory to rhG-CSF treatment and have no identical family donor. Bu + CY were given as conditioning. Case 1 and Case 2 received 6/6 and 5/6 HLA-matched unrelated umbilical cord blood, respectively. The number of infused nucleated cells was 6, 18 × 107/kg and CD34+ cell number was 3, 74 × 105/kg in Case 1. Those cell numbers were 8, 8 × 107/kg and 5, 34 × 105/kg for Case 2, respectively. Neutrophil/platelet engraftments were 45/49 days in Case 1 and 24/36 days in Case 2. Grade II cutaneous acute GVHD was seen in Case 2 that was treated successfully with prednisolone. Both patients are well with normal hematological findings and full donor chimerism for post-transplant 20 and 24 months, respectively. We conclude that UCB can be considered as a safe source of stem cell in patients with SCN who need urgent HSCT. [source] Successful cell-mediated cytokine-activated immunotherapy for relapsed acute myeloid leukemia after hematopoietic stem cell transplantationAMERICAN JOURNAL OF HEMATOLOGY, Issue 3 2009Benjamin Gesundheit Acute myeloid leukemia (AML) is an extremely aggressive disease with a high relapse rate even after allogeneic hematopoietic stem cell transplantation (HSCT). We report the successful outcome of cell-mediated cytokine-activated immunotherapy in a high-risk pediatric AML patient who relapsed shortly after allogeneic HSCT. Donor lymphocyte infusion along with interferon induced a graft-versus-leukemia effect, presenting as a reversible episode of graft-versus-host disease, which led to stable complete donor chimerism and total eradication of AML for over 24 months, at the time of this report. The curative potential of immunotherapy in hematological malignancies is discussed. Am. J. Hematol., 2009. © 2008 Wiley-Liss, Inc. [source] Polyclonal anti-T-cell globulin as part of the preparative regimen for pediatric allogeneic stem-cell transplantationPEDIATRIC TRANSPLANTATION, Issue 4 2001Mats Remberger Abstract: To prevent graft rejection and graft-versus-host disease (GvHD) after allogeneic stem-cell transplantation (ASCT), 56 children were given polyclonal anti-T-cell globulin (ATG) as part of the conditioning regimen. Of the 56 children in the cohort, 27 had a non-malignant disease and 29 had different hematological malignancies. Eight were in first remission of leukemia and the remainder in later stages. Donors were in 16 cases a human leucocyte antigen (HLA)-identical sibling and in 40 a matched unrelated donor (MUD). The control group comprised 16 patients with an HLA-identical donor; the children in this group were not treated with ATG. Side-effects related to the ATG treatment occured in 63% of the patients and included fever, chills, headache, dyspnoea, nausea/vomiting, body pain, fall in blood pressure, and transient respiratory arrest. Engraftment occured in 55 (98%) of the ATG-treated patients at a median of 17 (11,27) days after ASCT. One rejection occured at 23 days post-SCT. The probabilities of acute graft-versus-host disease (GvHD) of grades II,IV were 6% for patients with an HLA-identical donor, 12% for controls, and 26% for the MUD group. Chronic GvHD occured in 20%, 50%, and 50% of patients in the three groups, respectively. Transplant-related mortality rates at 100 days were 6%, 6%, and 7%, respectively. The 5-yr survival rate was 94% and 81% using sibling donors, with and without ATG respectively, and 53% using unrelated donors (p =,0.002). Disregarding donor type, among the ATG-treated patients 5-yr survival rates were 46% in patients with a malignant disease and 77% in non-malignant disorders. Relapse and relapse-free survival rates were 42% and 46%, respectively. Five out of 12 patients who showed an early full donor chimerism in the T-cell lineage developed acute GvHD of grades II,IV, compared to none out of 13 patients being mixed chimeras (p =,0.01). Hence, the use of polyclonal ATG as part of conditioning prior to ASCT in children is safe and the survival rate encouraging. [source] Graft rejection after hematopoietic cell transplantation with nonmyeloablative conditioningAMERICAN JOURNAL OF HEMATOLOGY, Issue 7 2008Tania N. Masmas Graft rejection after hematopoietic cell transplantation (HCT) with nonmyeloablative conditioning is a rare but serious clinical problem. Graft rejection and salvage therapy in eight patients in a retrospective analysis of 124 consecutive patients is reported. The patients were conditioned with low-dose fludarabine and total body irradiation (TBI). The association of pretransplantation risk factors with rejection and the effect of chimerism and graft-versus-host disease on rejection were analyzed. Overall survival (OS) and progression free survival (PFS) were compared between patients with and without rejection. Retransplantation was performed with increased TBI conditioning for all patients, and with increased mycophenolate mofetil doses for recipients with HLA-identical sibling donors. No known pretransplantation risk factors were confirmed in this study. Rejection episodes were unevenly distributed over time. The storage temperature of the apheresis products was identified as a risk factor for rejection. Storage of the apheresis products at 5°C diminished the risk of rejection. Low donor T cell chimerism at Day +14 significantly increased the risk of rejection. Seven patients were retransplanted. All but one engrafted successfully, but with decreased OS and PFS. Two patients received pentostatin infusion prior to donor lymphocyte infusions in unsuccessful attempts at reversing rejection. Storage temperature and donor chimerism had a significant effect on rejection. Following rejection, patients are at greater risk of dying from infections and progression/relapse of their malignancy. Retransplantation is feasible and well tolerated after HCT with nonmyeloablative conditioning and should be performed without delay in patients with imminent and manifest graft rejection. Am. J. Hematol. 2008. © 2008 Wiley-Liss, Inc. [source] Mixed chimerism and graft failure following conditioning with the fludarabine and cyclophosphamide nonablative regimen; Conversion to full donor chimerismAMERICAN JOURNAL OF HEMATOLOGY, Issue 6 2007Anand P. Jillella Abstract Twenty-one patients with hematologic malignancies were treated with the fludarabine (120,125 mg/m2) and cyclophosphamide (120 mg/kg) nonmyeloablative conditioning regimen. Graft versus host disease (GVHD) and graft rejection prophylaxis was with tacrolimus and mycophenolate mofetil. Thirteen of the 21 patients (62%) had mixed chimerism (,,90% donor cells) at day 60 and 11 (52%) of these patients had mixed chimerism which persisted until day 100. Immunosuppression was discontinued in 12 of 13 patients and two of them converted to full chimerism by day 100. Eight patients received a donor lymphocyte infusion (DLI) and five of them converted to full donor chimerism with DLI alone. Two patients were given GM-CSF in addition to a DLI with conversion to full donor chimerism. Three patients (14%) had graft failure requiring a second transplant using fludarabine (125 mg/m2) and melphalan (140 mg/m2). With a median followup of 2.8 years, 15 patients are alive,one with disease and 14 with no disease. Two patients died of acute GVHD, one of chronic GVHD, and three due to progressive disease. We conclude that the nonmyeloablative fludarabine/cyclophosphamide regimen results in a significant incidence of mixed chimerism and graft rejection but is well tolerated. We suggest a more intense regimen, such as fludarabine and melphalan, be used in patients with a high risk of early disease progression to establish early engraftment and graft versus tumor effect. Am. J. Hematol., 2007. © 2007 Wiley-Liss, Inc. [source] Double cord blood transplantation in patients with high risk bone marrow failure syndromesBRITISH JOURNAL OF HAEMATOLOGY, Issue 3 2008A. Ruggeri Summary Patients with bone marrow failure syndromes (BMFS) who reject a first allogeneic transplant or fail immunosuppressive therapy (IST) have an especially grim prognosis. We report 14 patients (eight adults, six children) transplanted with double cord blood transplantation (dUCBT) for BMFS. Neutrophil recovery was observed in eight patients, with full donor chimerism of one unit, and acute GVHD in 10. With a median follow-up of 23 months, the estimated 2 years overall survival was 80 ± 17% and 33 ± 16% for patients with acquired and inherited BMFS, respectively. Transplantation of two partially HLA-matched UCB thus enables salvage treatment of high-risk patients with BMFS. [source] Capillary electrophoresis for chimerism monitoring by PCR amplification of microsatellite markers after allogeneic hematopoietic cell transplantationCLINICAL TRANSPLANTATION, Issue 3 2005Alexandros Spyridonidis Abstract:, Background:, Hematopoietic chimerism has been demonstrated to be relevant for donor cell engraftment and detection of minimal residual disease after allogeneic hematopoietic cell transplantation (aHCT). In the light of increasing numbers of non-myeloablative aHCT as a treatment modality sensitive, rapid, and accurate chimerism monitoring techniques acquire novel relevance. Methods:, We evaluated the informativeness of five microsatellite markers in 376 donor/recipient pairs and evaluated the ability of capillary electrophoresis to detect mixed chimerism after aHCT. The sensitivity for capillary electrophoresis with respect to different markers was determined by limiting dilution assays with mixed chimerism samples containing defined amounts of cells or DNA. Furthermore, capillary electrophoresis was applied in 17 retrospectively selected patients with a mixed chimerism detected previously by gel electrophoresis, having undergone aHCT for different hematologic diseases and initially achieving a complete donor chimerism. Results:, In 163 of 165 (98%) of all related and 210 of 211 (99%) unrelated transplants the microsatellites identified informative alleles. The sensitivity and accuracy was higher with capillary electrophoresis when compared with gel electrophoresis with three of five microsatellites. Potential pitfalls with the application of capillary electrophoresis was preferential amplification and the occurrence of stutter peaks in the representative area. Investigation of the selected patient samples demonstrated that detection of a mixed chimerism was earlier with capillary electrophoresis when compared with gel electrophoresis. The detected recipient genotype by capillary electrophoresis examination, despite a negative gel electrophoresis result, ranged from 0.7 to 7.1%. Conclusions:, We conclude that chimerism assessment with our five microsatellites identified informative alleles in 99% of all donor/recipient pairs and may therefore be of use when establishing an institutional chimerism testing procedure. Capillary electrophoresis displayed a high sensitivity and accuracy for detecting a mixed chimerism in vitro and in vivo. [source] |