Effects of the intensity and timing of asbestos exposure on lung cancer risk at two mining areas in Quebec

BACKGROUND: Bone marrow transplantation (BMT) has been limited in the past by the availability of matched donors for patients. Over the past decade, the use of umbilical cord blood (UCB) as a source of hematopoietic stem cells has revolutionized the field of BMT, providing a source of hematopoietic stem cells for an increasing number of patients in need of a transplant. RESULTS: Umbilical cord blood transplantation (UCBT) appears to result in sustained engraftment of donor hematopoiesis similar to results achieved with marrow and peripheral blood hematopoietic stem cells. Early results indicate that UCBT is associated with a lower incidence and less severity of graft-versus-host disease than other sources of stem cells, potentially decreasing the morbidity and mortality of BMT. As the potential of UCBT has been realized, cord blood storage facilities have been established to provide UCB. The rapid emergence of UCBT has transformed a waste product of birth into a life-saving resource. Its use, however; has raised numerous ethical and medical concerns unique to this alternative source of stem cells. CONCLUSIONS: Umbilical cord blood transplantation represents a major advance in providing another stem cell source to patients in need of allogeneic hematopoietic stem cell transplantation. As with all new technologies, UCBT will have to be carefully studied over the next several years to determine its safety, efficacy, and precise indications in comparison with other sources of hematopoietic stem cells. The ethics of UCBT must properly respect the rights and needs of both donors and recipients.     

Chimerism analysis in long-term survivor patients after bone marrow transplantation for severe aplastic anemia

BACKGROUND AND OBJECTIVE: Allogeneic bone marrow transplantation (BMT) is the most common treatment for young patients with severe aplastic anemia (SAA). Late graft failure represents one of the possible unfavorable outcomes in this setting. Mixed chimerism might represent a risk factor for late graft failure. We examined this relationship by studying chimerism in long-term survivor SAA patients after allogeneic BMT. METHODS: We analyzed long-term hematopoietic chimerism in 15 patients who received BMTs for SAA: 9 with an irradiation-based conditioning regimen and 6 with ATG. We used a PCR method targeting VNTR loci. Sensitivity of the technique ranged between 0.5 and 1.5%. RESULTS: All patients conditioned with radiation-based schemes showed complete donor chimerism. Conversely, out of six patients who received cyclophosphamide and ATG as a conditioning regimen, only one of them had late graft failure (day +168). In this patient, durable mixed chimera status was first detected two months after BMT. INTERPRETATION AND CONCLUSIONS: Our results suggest that in long-term survivors of SAA after BMT there is almost always complete donor chimerism in both irradiated and ATG-conditioned recipients. Mixed chimerism might predict graft failure in these patients.     

Re: Mental health treatment in Ontario

A 2.5-year-old girl with neurogenic Gaucher's disease was transplanted with donor bone marrow from her HLA-compatible 12-year-old brother whose marrow was harvested 30 min post-mortem, after he suffered a severe head and neck injury. The marrow was stored in liquid nitrogen for 30 days prior to infusion. The post-transplantation period was uneventful with good engraftment and no signs of graft-versus-host disease. Currently, 6 months post-allogeneic bone marrow transplantation (alloBMT), analysis of both bone marrow and blood samples by PCR documented only cells of donor origin. This case demonstrates the feasibility of cadaveric marrow as a source of donor cells. To our knowledge, this patient is the only survivor of alloBMT from a cadaveric donor.     

DNA polymorphism, allogenic bone marrow transplantation and peripheral cell chimerism

BACKGROUND: Bone marrow transplantation or transplantation of peripheral stem cells is an effective treatment of a number of diseases. Its increasing success and expanding use in associated with the development of molecular diagnostic methods which enable to follow up the graft from its engraftment in a recipient and then during the whole posttransplantation period at the level extremely small numbers of cells. METHODS AND RESULTS: In peripheral blood of patients, genotypes of the following loci were examined by polymerase chain reaction (PCR): APOB, COL2A1, D17S20, D1S80, HVR/1G, SRY and AMXY. Technique of restriction analysis was used for loci DXYS20 and DXYS75. 1. The first signs of donor bone marrow activity were observed in 50% of patients already at the beginning of the second week after transplantation, while in the second half of patients increasing number of donor cells in peripheral blood was noticed in the second and third week. 2. Engraftment with full and permanent substitution of own bone marrow without presence of recipients cells in peripheral blood--complete chimerism--was achieved only in a part of patients (cca 50%). 3. Peripheral blood of other patients did not contain only donor cells but also recipients cells--mixed chimerism. With regard to its onset, the authors have divided mixed chimerism into early and late, taking into account that some patients can develop both types. In patients under study, early chimerism was found more frequently, which apparently resulted from a shorter period of observation of lately transplanted patients. 4. In cases of oncohaematologic patients, which allowed to study specifically the presence of a pathologic clone, the follow-up of chimerism enabled to distinguish between relapse of the original disease and "biologic" recovery--resurrection of original disease-free haematopoiesis. 5. Regression of mixed chimerism was supposed to be the result of treatment focused at the original disease (CML), in some patients, however, it was a spontaneous process. CONCLUSIONS: Follow-up of cellular chimerism in transplanted patients by means of molecular genetic methods provides substantial information about patient's shape which can be utilized it is necessary to decide on treatment procedures. For this reason it is desirable that examination of chimerism by molecular methods should form integral part of care of these patients.     

Treatment of chronic myeloid leukemia in relapse after umbilical cord blood transplantation

Umbilical cord blood (UCB) is increasingly used as a source of hematopoietic progenitor cells for allotransplantation. Donor-derived buffy coat cells are considered optimal treatment for leukemia relapses after transplantation of allogeneic bone marrow. Experience with relapses after UCB transplants are sparse. Here we report a girl who received an UCB transplant for chronic myeloid leukemia, relapsed after three years, failed to respond to donor buffy coat cells, but achieved a complete hematologic, cytogenetic, and molecular remission on interferon-alpha.     

Proliferative activity and loss of function of tumour suppressor genes as ''biomarkers'' in diagnosis and prognosis of benign and preneoplastic oral lesions and oral squamous cell carcinoma

Patients with hematologic malignancy or severe aplastic anemia after myeloablative chemo- and radiotherapy were given granulocyte colony-stimulating factor (G-CSF)-mobilized, cryopreserved allogeneic peripheral blood stem cells (PBSCs) from 15 healthy donors who were either human leukocyte antigen (HLA)-matched siblings (n = 13) or haploidentical offspring (2). Polymerase chain reaction-amplified short tandem repeat genotyping was used for early confirmation of donor engraftment after PBSC transplantation (PBSCT). A standard cyclosporine A/methotrexate combination was used to prevent acute graft-versus-host disease (GVHD). All donors, including one in the third trimester of pregnancy, tolerated G-CSF administration and 3-day PBSC harvesting procedures well. Engraftment was prompt for all patients; it was verified using a panel of 12 human polymorphic short tandem repeat loci from bone marrow as early as 7 days posttransplantation. This status was maintained until relapse, when mixed chimerism was detected using the polymerase chain reaction. A minimum resurgence of recipient cells to 1% of the population was required to detect chimerism. The median times to recovery of the absolute neutrophil count to greater than 0.5 x 10(9)/L and the sustained platelet count to greater than 20 x 10(9)/L without transfusion were 10 and 12 days after PBSCT, respectively. Six patients experienced acute GVHD, Grade I in two patients and Grade II in four, including two HLA-haploidentical recipients. Chronic GVHD was noticed in three of the 11 patients who were followed for at least 100 days after PBSCT. Ten patients were still alive at the latest follow-up and have been disease free for a median of 278 days (range 60-671). Five patients died from causes other than graft failure: three from leukemia relapse and two from transplant-related complications. The results confirm that G-CSF can be safely administered to healthy donors and that engraftment after allogeneic PBSCT is fast and durable. Complete chimerism can be detected early by genomic analysis. PBSCT may offer an alternative to bone marrow transplantation.     

Engraftment of HLA-matched sibling hematopoietic stem cells after immunosuppressive conditioning regimen in patients with hematologic neoplasias

BACKGROUND AND OBJECTIVE: The main objective of this pilot study was to assess the possibility of achieving engraftment of HLA-matched sibling donor mobilized hematopoietic stem cells after immunosuppressive non-myeloablative therapy. The second objective was to verify whether high-dose therapy with autologous stem cells rescue followed by allografting conditioned by only an immunosuppressive regimen, can be combined in order to achieve the reduction of tumor burden after autografting and the control of residual disease with immune-mediated effects after allografting. DESIGN AND METHODS: To enter the pilot study the patients had to fulfil the following criteria: advanced resistant disease, presence of an HLA matched sibling donor, no general contraindications to stem cell transplantation. Our data refers to 9 patients: Hodgkin's disease (n = 4), non-Hodgkin's lymphoma (n = 2), advanced chronic myelogenous leukemia (n = 2) (one patient with accelerated phase Ph-negative but p190 BCR-ABL gene positive by RT-PCR and one with Ph-positive blastic phase), refractory anemia with excess of blasts t(1;3) (p36;q21) (n = 1). All patients but one received the combined approach. At a median of 40 days (range 30-96), after high-dose therapy and autologous stem cell engraftment, the patients were treated with immunosuppressive therapy consisting of fludarabine and cyclophosphamide (Flu-Cy protocol) and then HLA matched donor mobilized stem cells were infused into the patients. GvHD prophylaxis consisted of cyclosporin and methotrexate. RESULTS: To date, with a median observation period of 4 months (range, 2-10), complete chimerism (100% donor cells) has been achieved in 6 patients. Three patients did not achieve complete chimerism: one patient died of progressive Hodgkin's disease when he reached 55% of donor cells, another patient is now in increasing phase of donor cell engraftment and the last patient (blastic phase-CML) was the only case who appears to have had autologous recovery. Two of the Hodgkin's disease patients, who were in partial remission after autografting, achieved complete remission after allografting and both are disease free 2 and 6 months after. Another Hodgkin's disease patient is alive at 10 months but she has progressive disease. One of the two patients with non-Hodgkin's lymphoma, who achieved partial remission after autografting, obtained complete remission and he is disease free 2 months after allografting. The other patient maintains partial remission obtained after autografting. The accelerated phase-CML patient obtained hematologic and molecular remission; the RAEB patient achieved hematologic and cytogenetic remission. In two patients severe aGVHD (grade II-III) was the single major complication but neither patient died of it. Mild aGVHD was seen in another patient. In only one patient did the ANC decrease to below 1 x 10(9)/L and in no case did platelets decrease below 20 x 10(9)/L. No patients required a sterile room or any red cell or platelet transfusions. INTERPRETATION AND CONCLUSIONS: Immunosuppressive therapy with a Flu-Cy protocol allowed engraftment of HLA-matched sibling donor stem cells without procedure-related deaths; moreover, we have demonstrated that this combined procedure can be pursued in safety in a serious ill population and some of these patients achieved a complete remission. This procedure is not likely to be curative, but a fascinating step along the path to curing these diseases. Of course, the follow-up is too short to document the incidence of cGvHD.     

Radiation dose-fractionation and dose-rate relationships for long-term repopulating hemopoietic stem cells in a murine bone marrow transplant model

Fractionated and low-dose-rate total-body irradiation (TBI) were compared with single-dose high-dose-rate TBI for induction of long-term hemopoietic chimerism in a murine syngeneic bone marrow transplantation model. At 5 months after TBI and bone marrow transplantation, the degree of stable blood chimerism was determined from the proportion of stem cell-derived donor (B6-Gpi-1a) and host (B6-Gpi-1b) blood erythrocytes. This end point was used to construct radiation dose-response curves for long-term donor marrow engraftment corresponding to ablation of primitive bone marrow stem cells of the host. Increasing dose fractionation and decreasing dose rate had the effect of restoring host hemopoiesis and required higher TBI doses for equal donor engraftment. Most of the dose recovery occurred within the first 6 h between fractions, consistent with the kinetics of sublethal damage repair. The late chimerism data were fitted to the linear-quadratic model using indirect and direct analysis for a fixed threshold response. Both analyses gave relatively low alpha/beta ratios (below 2 Gy), within the range normally seen in late-responding tissues. The dose-rate data gave a repair half-time of 2 h as estimated by the incomplete-repair model. These estimates contrast with the much higher alpha/beta values and lower repair half-times derived from acute hemopoietic failure as indicated by LD50/30, with the implication that separate target cell populations with differing radiosensitivities are involved in these two bone marrow end points.     

非血缘脐血造血干细胞移植的现状

脐血是骨髓和外周血干细胞以外的新的干细胞主要来源,脐血移植特别是非血缘脐血移植( UCBT)的数量逐年增加。UCBT存在的主要问题在于脐血的造血干/祖细胞(HSC/HPC)数量少,可能导致植入延迟或植入失败。临床上采用多种方法来提高脐血HSC/HPC的数量,包括双份脐血输注、减低强度的预处理、体内体外扩增脐血细胞、同时输注单倍体血缘供者CD34+细胞或间充质干细胞( MSC)、或将脐血细胞直接注入骨髓等,取得了良好的疗效。UCBT将会成为更多患者的治疗选择。     

Role of rHuEpo on blood transfusions in preterm infants after the fifteenth day of life

Ex vivo T cell depletion of allogeneic grafts is associated with a high (up to 80%) rate of mixed chimerism (MC) posttransplantation. The number of transplanted progenitor cells is an important factor in achieving complete donor chimerism in the T cell depletion setting. Use of granulocyte colony-stimulating factor (G-CSF) peripheral blood allografts allows the administration of large numbers of CD34+ cells. We studied the chimeric status of 13 patients who received allogeneic CD34+-selected peripheral blood progenitor cell transplants (allo-PBPCTs/CD34+) from HLA-identical sibling donors. Patients were conditioned with cyclophosphamide (120 mg/kg) and total-body irradiation (13 Gy in four fractions). Apheresis products were T cell-depleted by the immunoadsorption avidin-biotin method. The median number of CD34+ and CD3+ cells infused was 2.8x10(6)/kg (range 1.9-8.6x10(6)/kg) and 0.4x10(6)/kg (range 0.3-1x10(6)/kg), respectively. Molecular analysis of the engraftment was performed using polymerase chain reaction (PCR) amplification of highly polymorphic short tandem repeat (PCR-STR) sequences in peripheral blood samples. MC was detected in two (15%) of 13 patients. These two patients relapsed at 8 and 10 months after transplant, respectively. The remaining 11 patients showed complete donor chimerism and were in clinical remission after a maximum follow-up period of 24 months (range 6-24 months). These results were compared with those obtained in 10 patients who were treated with T cell-depleted bone marrow transplantation by means of elutriation and who received the same conditioning treatment and similar amounts of CD3+ cells (median 0.45x10(6)/kg; not significant) but a lower number of CD34+ cells (median 0.8x10(6)/kg; p = 0.001). MC was documented in six of 10 patients (60%), which was significantly higher than in the allo-PBPCT/CD34+ group (p = 0.04). We conclude that a high frequency of complete donor chimerism is achieved in patients receiving allo-PBPCT/CD34+ and that this is most likely due to the high number of progenitor cells administered.     

Engraftment of allogeneic hematopoietic progenitor cells with purine analog-containing chemotherapy: harnessing graft-versus-leukemia without myeloablative therapy

The immune-mediated graft-versus-leukemia effect is important to prevent relapse after allogeneic progenitor cell transplantation. This process requires engraftment of donor immuno-competent cells. The objective of this study was to assess the feasibility of achieving engraftment of allogeneic peripheral blood or bone marrow progenitor cell after purine analog containing nonmyeloablative chemotherapy. Patients with advanced leukemia or myelodysplastic syndromes (MDS) who were not candidates for a conventional myeloablative therapy because of older age or organ dysfunction were eligible. All patients had an HLA-identical or one-antigen-mismatched related donor. Fifteen patients were treated (13 with acute myeloid leukemia and 2 with MDS). The median age was 59 years (range, 27 to 71 years). Twelve patients were either refractory to therapy or beyond first relapse. Eight patients received fludarabine at 30 mg/m2/d for 4 days with idarubicin at 12 mg/m2/d for 3 days and ara-c at 2 g/m2/d for 4 days (n = 7) or melphalan at 140 mg/m2/d (n = 1). Seven patients received 2-chloro-deoxyadenosine at 12 mg/m2/d for 5 days and ara-C 1 at g/m2/d for 5 days. Thirteen patients received allogeneic peripheral blood stem cells and 1 received bone marrow after chemotherapy. Graft-versus-host disease (GVHD) prophylaxis consisted of cyclosporine and methyl-prednisolone. Treatment was generally well tolerated, with only 1 death from multiorgan failure before receiving stem cells. Thirteen patients achieved a neutrophil count of greater than 0.5 x 10(9)/L a median of 10 days postinfusion (range, 8 to 17 days). Ten patients achieved platelet counts of 20 x 10(9)/L a median of 13 days after progenitor cell infusion (range, 7 to 78 days). Eight patients achieved complete remissions (bone marrow blasts were < 5% with neutrophil recovery and platelet transfusion independence) that lasted a median of 60 days posttransplantation (range, 34 to 170+ days). Acute GVHD grade > or = 2 occurred in 3 patients. Chimerism analysis of bone marrow cells in 6 of 8 patients achieving remission showed > or = 90% donor cells between 14 and 30 days postinfusion, and 3 of 4 patients remaining in remission between 60 and 90 days continued to have > or = 80% donor cells. We conclude that purine analog-containing nonmyeloablative regimens allow engraftment of HLA-compatible hematopoietic progenitor cells. This approach permits us to explore the graft-versus-leukemia effect without the toxicity of myeloablative therapy and warrants further study in patients with leukemia who are ineligible for conventional transplantation with myeloablative regimens either because of age or concurrent medical conditions.     

Specific tolerance induction and transplantation: a single-day protocol

Bone marrow transfusion is a well-established method for induction of mixed hematopoietic chimerism and donor-specific tolerance in animal models. This procedure, however, is inapplicable in clinical transplantation using cadaveric donors due to the interval (1 week to 7 months) between tolerance induction and organ transplantation. For clinical use, it is essential that allografts be placed at the time of bone marrow transfusion. In the present study, we performed skin transplantation within 1 hour after a nonlethal conditioning regimen. Recipient mice were treated with anti-CD3, anti-CD4, low-dose total body irradiation (3 to 6 Gy TBI) and fully mismatched or haploidentical donor bone marrow cells. Stable multilineage chimerism and specific T-cell nonresponsiveness developed. Donor skin grafts were permanently accepted. These results suggest that this single day protocol has clear potential for application in both cadaveric and living-related organ transplantation.     

Prevention of graft-versus-host disease in rat small bowel transplantation by recipient pretreatment with UV-B-modulated bone marrow cells

UV-B irradiation (700 J/m2) of bone marrow cells (BMC) before transplantation into lethally irradiated (1050R) allogeneic rats prevents graft-versus-host disease (GVHD) and results in stable chimerism. This study examined whether UV-B modulation of BMT is useful in the subsequent induction of tolerance to small bowel transplant (SBT) and avoids the danger of GVHD, which remains the major obstacle to successful SBT. Lethally irradiated Lewis recipients of UV-B irradiated (700 J/m2) BMT (10(8) BMC admixed with 5 x 10(6) splenic leukocytes) either from ACI or Wistar-Furth (WF) rats developed stable chimerism without any evidence of GVHD for > 360 days. Lewis recipients of UV-B ACI BMC expressed 95 +/- 6% ACI lymphoid cells at 50 and 150 days after BMT using complement-dependent cytotoxicity assay. Unmodified Lewis recipients of orthotopic ACI SBT rejected their grafts and died in 7-9 days, whereas Lewis chimeras accepted permanently (> 200 days) bone marrow donor (ACI) SBT without any evidence of GVHD when the SBT was performed at 60 or 150 days after BMT. In contrast, when SBT was performed, only 30 days after induction of chimerism with UV-B ACI BMT, the recipients developed severe GVHD and died between 17 and 21 days. The Lewis chimeras rejected third part (WF) SBT acutely and died in 7-9 days, thus demonstrating the specificity of the induction of tolerance in this model. That this immunologic unresponsiveness is not restricted by the recipient-donor rat strain combination was shown by the permanent acceptance of WF SBT without GVHD by Lewis/WF chimeric recipients. Furthermore, the Lewis chimeras that were made diabetic with STZ 28 days after BMT permanently accepted (> 300 days) BM donor-type (WF) and recipient-type (Lewis) islet cells and became normoglycemic, thus indicating tolerance to both donor and recipient Ags. The diabetic Lewis chimeras that became normoglycemic permanently accepted (> 200 days) WF SBT without any evidence of GVHD after donor-type SBT 110 days after WF islet transplantation. The apparent lack of organ-specific unresponsiveness in this model confirmed our previous observation with combined islet and heart transplants. In vitro MLR studies showed that the chimeric animals were specifically unreactive to donor- and recipient-type alloantigens. Our results demonstrate that UV-B irradiation of BMT is a promising approach to the induction of tolerance to SBT.     

Dominant selection system for use in Cryptococcus neoformans

BACKGROUND: Approximately one-fourth of patients who could benefit from bone marrow transplantation (BMT) are served by a genotypically identical sibling donor. When patients do not have an HLA-matched donor, alternative marrow sources should be explored. The way to allow survival in some patients is to perform two- or three loci HLA mismatched BMT. Preliminary results with BMT in partially-matched, related donors performed at Veterans General Hospital-Taipei are reported. METHODS: Between 1985 and 1994, a total of 121 patients were enrolled in this study. Ten patients received BMT with HLA partially-matched, related donor, including 2 acute nonlymphocytic leukemia (ANLL), 5 chronic myelocytic leukemia (CML) and 3 severe aplastic anemia (SAA). Three and four hematologically malignant patients received cyclophosphamide (Cy) + radiotherapy (RT) and Cy + Busulfan(Bu) preconditioning regimens, respectively; three SAA patients received standard Cy + RT regimen. Additional prophylaxis against graft-versus-host disease (GVHD) consisted of methotrexate (MTX) and cyclosporin-A (CSA). The median follow up was 36 months. Seven were 2-loci disparate and 3 were 3-loci. RESULTS: Engraftment developed with a mean of 20.9 days after transplant. Nonengraftment rate was 1/10 (10%), delayed graft failure 2/10(20%) and venoocculsive disease (VOD) 1/10(10%). The percentage of patients who developed grade II to IV acute GVHD was low (13.6% of those mismatched at 0 locus, 31.6% mismatched at 1 loci and 14.3% at > or = 2 loci. p = 0.181). Extensive chronic GVHD occurred in 16.7% (34.1% of those mismatched at 0 locus, 41.2% mismatched at 1 loci and 16.7% at 2 loci. p = 0.492). There were five deaths. The other 5 still survived at 36 months of follow-up. Log-rank analysis revealed no statistical significance between those mismatched at > or = 2 vs at 1 (p = 0.146) but the difference between those mismatched at > or = 2 and at 0 (p = 0.0359) was statistically significant. CONCLUSIONS: When patients requiring BMT without an HLA identical sibling donor, an alternative transplant from haploidentical family members remains a viable option, especially when a patient has CML, SAA or other refractory hematologic malignancies.     

Nonmyeloablative stem cell transplantation and cell therapy as an alternative to conventional bone marrow transplantation with lethal cytoreduction for the treatment of malignant and nonmalignant hematologic diseases

Myeloablative conditioning associated with hazardous immediate and late complications is considered as a mandatory first step in preparation for allogeneic blood or marrow transplantation (allogeneic BMT) for the treatment of malignant hematologic disorders and genetic diseases. Immune-mediated graft-versus-leukemia (GVL) effects constitute the major benefit of allogeneic BMT. Therefore, we have introduced the use of relatively nonmyeloablative conditioning before allogeneic BMT aiming for establishing host-versus-graft tolerance for engraftment of donor immunohematopoietic cells for induction of GVL effects to displace residual malignant or genetically abnormal host cells. Our preliminary data in 26 patients with standard indications for allogeneic BMT, including acute leukemia (n = 10); chronic leukemia (n = 8), non-Hodgkin's lymphoma (n = 2), myelodysplastic syndrome (n = 1), multiple myeloma (n = 1), and genetic diseases (n = 4) suggest that nonmyeloablative conditioning including fludarabine, anti-T-lymphocyte globulin, and low-dose busulfan (8 mg/kg) is extremely well tolerated, with no severe procedure-related toxicity. Granulocyte colony-stimulating factor mobilized blood stem cell transplantation with standard dose of cyclosporin A as the sole anti-graft-versus-host disease (GVHD) prophylaxis resulted in stable partial (n = 9) or complete (n = 17) chimerism. In 9 patients absolute neutrophil count (ANC) did not decrease to below 0.1 x 10(9)/L whereas 2 patients never experienced ANC < 0.5 x 10(9)/L. ANC > or = 0.5 x 10(9)/L was accomplished within 10 to 32 (median, 15) days. Platelet counts did not decrease to below 20 x 10(9)/L in 4 patients requiring no platelet support at all; overall platelet counts > 20 x 10(9)/L were achieved within 0 to 35 (median 12) days. Fourteen patients experienced no GVHD at all; severe GVHD (grades 3 and 4) was the single major complication and the cause of death in 4 patients, occurring after early discontinuation of cyclosporine A. Relapse was reversed by allogeneic cell therapy in 2/3 cases, currently with no residual host DNA (male) by cytogenetic analysis and polymerase chain reaction. To date, with an observation period extending over 1 year (median 8 months), 22 of 26 patients (85%) treated by allogeneic nonmyeloablative stem cell transplantation are alive, and 21 (81%) are disease-free. The actuarial probability of disease-free survival at 14 months is 77.5% (95% confidence interval, 53% to 90%). Successful eradication of malignant and genetically abnormal host hematopoietic cells by allogeneic nonmyeloablative stem cell transplantation represents a potential new approach for safer treatment of a large variety of clinical syndromes with an indication for allogeneic BMT. Transient mixed chimerism which may protect the host from severe acute GVHD may be successfully reversed postallogeneic BMT with graded increments of donor lymphocyte infusions, thus resulting in eradication of malignant or genetically abnormal progenitor cells of host origin.     

Giant cell fibroblastoma associated with dermatofibrosarcoma protuberans: a case report

Umbilical cord blood (UCB) was disclosed to possess the proliferative capacity containing hematopoietic progenitors and has recently been applied for allogeneic transplantation as an attractive alternative to bone marrow or peripheral blood stem cells. UCB contains similar and higher proportions of immature hematopoietic progenitors, compared to bone marrow stem cells, although the number of collectable cells is limited. The yield of collectable UCB volume ranges from 70 to 150 ml. The colony formation of CFU-Mix of UCB was higher, but that of CFU-GM and CFU-E was lower, compared to those of bone marrow. The analyses of expression of differentiation antigens and adhesion molecules on CD34+ cells of UCB by flow cytometer, revealed that the coexpression rates of CD38 and CD44 on CD34+ cells were almost the same, but the mean fluorescence intensity of those was low compared to adult bone marrow. These results indicate that UCB contains more primitive hematopoietic progenitors. UCB transplantation has greater advantages of lower incidences of graft versus host disease, and unlimited number of donors compared with other allogeneic transplantation would widen the indication of transplantation by technical and methodological development.     

Association between pretransplant interferon-alpha and outcome after unrelated donor marrow transplantation for chronic myelogenous leukemia in chronic phase

Treatment options for patients diagnosed with chronic myelogenous leukemia (CML) in chronic phase (CP) who lack a suitable related donor for marrow transplantation include hydroxyurea, interferon-alpha (IFN-alpha), or transplantation from an unrelated donor (URD). Most studies support the view that treatment with IFN-alpha results in prolonged survival compared with hydroxyurea therapy. Some patients are offered URD transplantation as a second-line treatment; however, the impact of pretransplant IFN-alpha on the outcome of URD transplantation is uncertain. To address this question, we evaluated the effect of pretransplant IFN-alpha therapy in 184 patients undergoing URD transplantation for CML in CP at a single center. Of the 184 patients, 114 did not receive IFN-alpha, whereas 22, 23, and 25 patients received IFN-alpha for, respectively, 1 to 5, 6 to 12, and more than 12 months before transplant. Pretransplant IFN-alpha therapy administered for > or = 6 months was associated with an increased risk of severe (grades III-IV) acute graft-versus-host disease (GVHD; relative risk [RR], 3.0; 95% confidence interval [CI], 1.4 to 6.2; P = .004) and mortality (RR, 2. 1; 95% CI, 1.3 to 3.5; P = .003) relative to less than 6 months or no IFN-alpha therapy. Increased mortality occurred between 100 and 365 days after transplant (P = .005), was limited to patients with severe acute GVHD, and was due to chronic GVHD refractory to immunosuppressive therapy. Other variables associated with mortality included HLA-DRB1 or DQB1 (but not HLA-A or B) mismatched donors, age greater than 50 years, weight > or = 110% of ideal body weight, and the absence of cytomegalovirus (CMV) or fungal prophylaxis. For patients treated with IFN-alpha for less than 6 months before transplant, who were < or = 50 years of age, received a HLA-A, B, DRB1, and DQB1 matched URD transplant, and received CMV and fungal prophylaxis after transplant (n = 48), survival was 87% +/- 5% at 5 years. These data provide a rationale for immediate transplantation in preference to extended treatment with IFN-alpha when the patient is < or = 50 years of age and has an HLA-compatible unrelated volunteer donor.     

Assessment of donor cell and matrix survival in fresh articular cartilage allografts in a goat model

The long-term survival of allografts of articular cartilage has been proposed to be dependent on the survival of the cells that maintain the unique structural and material properties of the allograft. In this study, we assessed cell survival in 24 fresh articular cartilage allografts of the medial plateau in a Spanish-goat model. A DNA-probe technique was used to distinguish clearly between DNA from donor (allograft) and host cells. The intraarticular survival of viable allograft chondrocytes in the transplanted articular cartilage started to diminish as early as 3 weeks after transplantation; however, there was considerable variation in the amount of donor cell DNA detected in the allografts at 6 and 12 months following transplantation. This contrasts with our experience with fresh allografts of ligament, tendon, and meniscus, in which no donor DNA was detected 4 weeks after transplantation. DNA from host cells was present in all articular cartilage allografts, as evidenced by detectable unique host DNA patterns. Histological and histochemical assays showed that none of the transplants demonstrated normal structure and composition at 1 year after transplantation. The grafts in which large quantities of donor DNA were present appeared grossly superior to those with no or reduced remaining demonstrable donor DNA.     

A single course of remission reinduction chemotherapy for acute myelogenous leukemia relapsing after allogeneic bone marrow transplantation is complicated by graft-versus-host disease and followed by sustained complete remission

Graft-versus-host disease (GVHD) remains a major immunological complication after allogeneic bone marrow transplantation (allo-BMT), but also favors development of the beneficial graft-versus-leukemia (GVL) effect. A patient with AML-M4 (inv (16)) is described, who was given non-myeloablative remission reinduction therapy for leukemic relapse (inv (16), trisomy 8) diagnosed on day 184 after HLA-compatible sibling BMT. On day 236, ie about 6 weeks after completion of this course, a clinical syndrome suggestive of acute GVHD grade 3 had developed. Skin biopsy confirmed the clinical diagnosis of GVHD, with a compatible liver biopsy. Transfusion-associated GVHD was ruled out by analysis of short tandem repeat (STR) alleles in the skin biopsy, revealing alleles from donor and recipient but not from third party origin. Cyclosporin A (CsA) therapy, which had been tapered between days 150 and 175, was resumed, resulting in a favorable response and gradual transition to limited chronic GVHD. The patient has since remained in complete remission with an excellent performance status for more than 40 months, without further chemotherapy. Thus this biopsy proven case of GVHD was induced by marrow donor lymphocytes more than 200 days after transplantation and apparently triggered by remission reinduction chemotherapy. The case indicates that intensive non-myeloablative chemotherapy can cure AML relapsing after allo-BMT. The therapeutic effect in this case probably involved a direct pharmacological suppression of the leukemic clone followed by a GVL effect initiated by donor-derived alloreactive T lymphocytes.