As unrelated allogeneic umbilical cord blood transplantation (UCBT) has been developed for 20 years already since 1988, more than ten thousands cases have cumulatively undergone UCBT over the world. A huge number of clinical data confirmed that UCBT had unique characters with low rate of severe GVHD. The efficacy and data on TRM, relapse and EFS of allogeneic UCBT with HLA 0-1 mismatched are similar to those in HLA matched BMT. UCBT has become the optimal choice for source of hematopoietic stem cells for allogeneic stem cell transplant especially when HLA-matched or haploidentical donors are not available in time. In most developed countries, unrelated allogeneic UCBT developed successively, and in recent years HLA mismatched UCBT with double units performed in adults increased even more rapidly than in children. Another recent trend of UCBT has been extending to treat some non-malignant but refractory diseases in pediatrics, such as severe combined immunodeficiency, thalassemia major, bone marrow failure syndrome and metabolic disorders. The clinical successful practice of double units for cord blood transplantation inspires to ponder over questions remaining mystery. What is the conflict like between two mismatched donor cells in vivo, which does not spoil the whole transplantation but enable the patient to be engrafted successfully without any increment of the dosage by the sum of two doses together? How can they both be taken at the same time firstly by the recipient, but why does only one predominate later? What are the factors enable the donor cells of the winner to sustain? With the references of the international experiences, how to solve the clinical encountered problems, perspective of unrelated allogeneic UCBT and proper strategies to be enacted are reviewed.
Cord Blood Stem Cell Transplantation ; adverse effects ; methods ; Humans ; Tissue Donors ; Transplantation, Homologous

Aim of this study was to compare the outcomes of transplantation by donor source and to help select the best alternative donor in children with leukemia. Donor sources included matched related donor (MRD, n = 35), allele-matched unrelated donor (M-UD, n = 10) or -mismatched (MM)-UD (n = 13) or unrelated umbilical cord blood (UCB, n = 11). UCB group had a significantly higher incidence of grade II-IV acute graft versus host disease (MRD, 11.8%; M-UD, 30.0%; MM-UD, 15.4%, UCB, 54.4%, P = 0.004) but there was no difference in incidence of chronic graft versus host disease between 4 groups. The 5-yr leukemia-free survival (LFS) was 76.7%, 60.0%, 69.2%, and 45.5%, respectively (P = 0.128). MRD group showed higher LFS rate than UCB group (P = 0.022). However, LFS of M-UD and MM-UD together (65.2%) was not different from that of MRD group (76.7%, P = 0.325), or from that of UCB (45.5%, P = 0.190). The relapse incidence at 5 yr was 17.1%, 20.0%, 15.4%, and 0%, respectively (P = 0.460). The 100-day treatment-related mortality was 2.9%, 20.0%, 7.7%, and 36.4%, respectively (P = 0.011). Despite the limitations of small number of patients, unrelated donor transplants including even allele-mismatched ones, seem to be as effective in children with leukemia lacking suitable relative donors. Also, UCB transplant may serve as another possible option in urgent transplants.
Adolescent ; Child ; Child, Preschool ; *Cord Blood Stem Cell Transplantation/adverse effects/methods ; Disease-Free Survival ; Female ; Fetal Blood/transplantation ; Graft vs Leukemia Effect ; *Hematopoietic Stem Cell Transplantation/adverse effects/methods/mortality ; Histocompatibility Testing ; Humans ; Infant ; Leukemia/mortality/*therapy ; Male ; Transplantation, Homologous ; Treatment Outcome ; Unrelated Donors

Allogeneic hematopoietic stem cell transplantation is the only curative therapy for severe beta-thalassemia. This time, the experience of utilizing HLA 2-loci mismatched sibling cord blood transplantation (CBT) in a child with severe beta-thalassemia was firstly reported in our country. A 3-year-male patient had been diagnosed with severe beta-thalassemia at 6 months of age (HbF 86.6%, HbA1 1.7%, HbA2 1.7%, beta globin gene mutation CD17, A-->T/IVS-II-654, C-->T). The patient's HLA typing was A 24,11, B 58,35 and DRB1 03,15. During a subsequent maternal pregnancy. The prenatal diagnosis for thalassemia and prenatal HLA typing analysis were performed on 18 weeks of pregnancy. The results indicated that the male fetus was a heterozygote (beta globin gene mutation N/CD17, A-->T), HLA typing was A 24,11, B 58,51 and DRB1 03,12. 120 ml cord blood was collected at time of delivery, the total numbers of nucleated cells, CFU-GM and CD34(+) cells were 1.830 x 10(9), 16.653 x 10(5) and 3.11 x 10(6), respectively. A new conditioning regimen including: hypertransfusion, continuous i.v. desferrioxamine, busulfan, cyclophosphamide, antithymocyte globulin plus hydroxyurea and fludarabine. GVHD prophylaxis comprised cyclosporin A and mycophenolate mofetil. The viability of cord blood at the time infusion was 92%, The total numbers of nucleated cells, CFU-GM and CD34(+) cells in the transfused cord blood were 12.06 x 10(7)/kg, 1.098 x 10(5)/kg, and 2.04 x 10(6)/kg, respectively. Results showed that the patient's clinical course after cord blood transplantation was unremarkable. Acute GVHD grade I developed on day 15, methylprednisolone 2 mg/kg was given to cure. Neutrophil engraftment (ANC > 0.5 x 10(9)/L) on day 17, platelet engraftment (> 50 x 10(9)/L) on day 50. The patients became independent from red blood cell transfusion since day 80 (when his hemoglobin level kept > 12.5 g/L). His beta globin gene mutation and HLA typing were all the same as the donor's analyzed on day 60 and 200. There was also a switch in blood group from A pre-transplant to O post-transplant. It is concluded that the new conditioning and GVHD prophylaxis regimens allow a successful engraftment in this case. This observation may contribute in developing UCBT as an alternative when matched sibling donors are not available.
Child, Preschool ; Cord Blood Stem Cell Transplantation ; adverse effects ; Globins ; genetics ; Graft vs Host Disease ; etiology ; HLA Antigens ; immunology ; Histocompatibility ; genetics ; immunology ; Histocompatibility Testing ; methods ; Humans ; Male ; Mutation ; Siblings ; Transplantation Tolerance ; immunology ; Transplantation, Homologous ; beta-Thalassemia ; therapy

Blood Donors ; Child ; Cord Blood Stem Cell Transplantation ; adverse effects ; methods ; Female ; Follow-Up Studies ; Graft vs Host Disease ; prevention & control ; Humans ; Infant, Newborn ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive ; surgery ; Transplantation, Homologous ; Treatment Outcome

OBJECTIVEFrom December 1998 to April 2004, 3960 umbilical cord blood units were stored in Guangzhou cord blood bank, which provided 100 umbilical cord blood units to 25 transplant center for 83 patients with malignant or non-malignant diseases. To study the related factors affecting unrelated umbilical cord blood stem cell transplantation, the authors analyzed retrospectively the results of transplantation of unrelated umbilical cord blood stem cells for 65 patients.

METHODSALL (acute lymphocytic leukemia) cord blood units were obtained from full term normal vaginal and cesarean deliveries in Guangzhou Women and Infants Hospital. The fractionation, cryopreservation and thawing of the cord blood were performed according to the regulations of New York umbilical cord blood bank and pertinent literature. The selection of cord blood was based on HLA typing and the number of nucleated cells. The sex and HLA antigens of donors were defined as the evidence of engraftment. Time to engraftment was recorded when the absolute number of neutrophil ANC (absolute neutrophil count) was higher than 5.0 x 10(8) for three days. Event-free survival and graft versus host disease (GVHD) were provided by transplant centers.

RESULTSOut of 65 patients who received unrelated cord blood stem cell transplant, 49 patients were diagnosed as having malignant diseases [including 23 with ALL, 16 with AML (acute myeloid leukemia), 7 with CML (chronic myelogenous leukemia), 3 with lymphoma and one with MDS (myelodysplastic syndrome)], 16 patients had non-malignant disease. The 65 transplanted patients (42 male, 23 female) had a median age of 10 years (range 1 - 33 years) and a median body weight of 27 kg (range 10 - 67 kg). The patients received cord blood stem cells from unrelated 0-locus (n = 9) or 1-locus (n = 43) or 2-locus (n = 13) HLA mismatched donor. The median dose of infused cells was: total neutrophil count (TNC) 5.7 x 10(7), CD(34)(+) 5.1 x 10(5), CFU-GM 3.8 x 10(4). Fifty of 65 (77%) patients had engraftment. GVHD occurred in 41 patients (63%), including acute grade I - II GVHD in 31 patients (76%), acute grade III - IV GVHD in 8 patients (20%) and chronic GVHD in 2 patients (5%). Fifty patients had engraftment (ANC > 5.0 x 10(8)) after a median time of 17 (range 7 to 44) days after transplant, while an autologous hematopoietic reconstitution was observed in 6 patients; 24 patients died of severe pneumonia (n = 8), acute GVHD (n = 4), or sepsis (n = 12) and the disease-free survival probability was 61%.

CONCLUSIONSUnrelated allogeneic umbilical cord blood transplantation may be a good substitution for unrelated allogeneic bone marrow transplantation with a good prospect.

Adolescent ; Adult ; Child ; Child, Preschool ; China ; Cord Blood Stem Cell Transplantation ; adverse effects ; methods ; Disease-Free Survival ; Female ; Graft vs Host Disease ; etiology ; mortality ; Humans ; Infant ; Leukemia ; mortality ; therapy ; Male ; Retrospective Studies ; Survival Rate ; Transplantation, Homologous ; Treatment Outcome ; Young Adult

Although mesenchymal stem cells (MSCs) are increasingly used to treat graft-versus-host disease (GVHD), their immune regulatory mechanism in the process is elusive. The present study aimed to investigate the curative effect of third-party umbilical cord blood-derived human MSCs (UCB-hMSCs) on GVHD patients after allogeneic hematopoietic stem cell transplantation (allo-HSCT) and their immune regulatory mechanism. Twenty-four refractory GVHD patients after allo-HSCT were treated with UCB-hMSCs. Immune cells including T lymphocyte subsets, NK cells, Treg cells and dendritic cells (DCs) and cytokines including interleukin-17 (IL-17) and tumor necrosis factor-alpha (TNF-α) were monitored before and after MSCs transfusion. The results showed that the symptoms of GVHD were alleviated significantly without increased relapse of primary disease and transplant-related complications after MSCs transfusion. The number of CD3(+), CD3(+)CD4(+) and CD3(+)CD8(+) cells decreased significantly, and that of NK cells remained unchanged, whereas the number of CD4(+) and CD8(+) Tregs increased and reached a peak at 4 weeks; the number of mature DCs, and the levels of TNF-α and IL-17 decreased and reached a trough at 2 weeks. It was concluded that MSCs ameliorate GVHD and spare GVL effect via immunoregulations.
Adolescent ; Adult ; Cord Blood Stem Cell Transplantation ; methods ; Cytokines ; metabolism ; Dendritic Cells ; metabolism ; Female ; Graft vs Host Disease ; immunology ; therapy ; Hematopoietic Stem Cell Transplantation ; adverse effects ; Humans ; Immunomodulation ; Killer Cells, Natural ; metabolism ; Male ; T-Lymphocyte Subsets ; metabolism ; Transplantation, Homologous ; adverse effects ; Young Adult

Anemia, Aplastic ; physiopathology ; therapy ; Child ; Child, Preschool ; China ; Cord Blood Stem Cell Transplantation ; adverse effects ; methods ; Female ; Graft Survival ; Graft vs Host Disease ; etiology ; immunology ; therapy ; HLA Antigens ; blood ; immunology ; Histocompatibility ; immunology ; Histocompatibility Testing ; Humans ; Male ; Treatment Outcome

BACKGROUNDWide application of umbilical cord blood transplantation (UCBT) in adult patients is limited by low cell-dose available in one umbilical cord blood (UCB) unit. The aim of this study was to investigate the safety and long-term outcomes of UCBT from unrelated donors in adult and adolescent patients with leukemia.

METHODSThirteen patients with leukemia received double-unit UCBT with human leukocyte antigen (HLA) mismatched at 0 - 2 loci. We analyzed the engraftment, graft-versus-host disease (GVHD) and survival.

RESULTSTwelve evaluable patients (92.3%) had neutrophil and platelet engraftment at a median of 21 days (range, 16-38 days) and 34 days (range, 25 - 51 days), respectively. At day 30, engraftment was derived from one donor in 8 patients (66.7%, 95%CI 40.0% - 93.4%), and from both donors in 4 patients (33.3%, 95%CI 6.7% - 60.0%) with 1 unit predominated. Unit with larger nucleated cell (NC) dose would predominate in engraftment (P = 0.039), whereas CD34(+) cell dose or HLA-match failed to demonstrate any relationship with unit predominance. Only one patient developed grade II acute graft-versus-host disease (aGVHD). Chronic GVHD (cGVHD) was observed in 2 of 11 patients who survived more than 100 days, and both were limited. The median follow-up after transplantation for the 13 patients was 45 months (range 1.5 - 121.0 months) and 72 months (range 41.0 - 121.0 months) for the 8 alive and with full donor chimerism. The 5-year cumulative disease free survival (DFS) was (61.5 ± 13.5)%. Of the 13 patients, 5 patients died in 1 year and 1-year transplantation related mortality (TRM) was 23.1% (95%CI 0.2% - 46.0%).

CONCLUSIONDouble-unit UCBT from unrelated donors with HLA-mismatched at 0-2 loci may overcome the cell-dose barrier and be feasible for adults and adolescents with leukemia.

Adolescent ; Adult ; Cord Blood Stem Cell Transplantation ; adverse effects ; methods ; Disease-Free Survival ; Female ; Graft vs Host Disease ; etiology ; Humans ; Leukemia ; immunology ; mortality ; therapy ; Male ; Treatment Outcome ; Young Adult

In order to research the related factors of umbilical cord blood transplantation, 54 cases of unrelated umbilical cord blood transplantation were analyzed retrospectively, which were performed from June 1998 to July 2003. All cord blood units were obtained from full term normal vaginal deliveries in Guangzhou Maternal-Neonatal Hospital. The fractionation, cryopreservation and thawing of cord blood have been done according to the regulation of New York umbilical cord blood bank and pertinent literature. The selection of cord blood is based on HLA typing and the number of nucleated cells. The results showed that from June 1998 to July 2003, 3 475 units of cord blood were collected in Guangzhou Umbilical Cord Blood Bank and 99 units were provided for therapy of 85 patients in 21 transplantation centers, including 11 sibling and 74 unrelated cord blood transplantations. 54 cases of unrelated cord blood transplantation were reported, including 43 malignant diseases and 11 non-malignant diseases. The median age of recipients was 9.5 (range 1.2 - 33) years, the median weight was 27 (range 10 - 60) kg, the median number of TNC was 6.82 x 10(7)/kg, 43 cord blood were implanted (ANC > 500/microl) at day 60 after transplantation (79.6%, median 17). The time of nuclear cell reconstitution after cord blood transplantation was statistically related with nucleated cells and the type of disease, not related with HLA matching. Acute GVHD was present in 8 patients (21.6%) and chronic GVHD occurred in 2 patients (5.4%), 6 patients suffered from graft failure (11.1%). The total survival rate was 42.6%. It is suggested that unrelated umbilical cord blood transplantation seems to be a good substitute for bone marrow transplantation and has good prospects especially in children.
Acute Disease ; Adolescent ; Child ; Child, Preschool ; China ; Cord Blood Stem Cell Transplantation ; adverse effects ; methods ; Female ; Graft vs Host Disease ; etiology ; mortality ; Humans ; Leukemia ; surgery ; Male ; Retrospective Studies ; Survival Rate

Despite the prophylaxis and preemptive strategies using potent antiviral agents, cytomegalovirus (CMV) remains a major infectious cause of morbidity and mortality in allogeneic stem cell transplantation (SCT) recipients. Delayed immune reconstitution after SCT, such as cord blood and T-cell depleted SCT with the use of alemtuzumab, has been associated with an increased frequency of CMV disease as well as CMV reactivation. CMV disease involving central nervous system is an unusual presentation in the setting of SCT. We report a case of CMV ventriculoencephalitis after unrelated double cord blood SCT with an alemtuzumab-containing preparative regimen for Philadelphia-positive acute lymphoblastic leukemia.
Antibodies, Monoclonal/pharmacology/*therapeutic use ; Antibodies, Monoclonal, Humanized ; Antibodies, Neoplasm/pharmacology/*therapeutic use ; Antineoplastic Agents/pharmacology/*therapeutic use ; Cord Blood Stem Cell Transplantation/*adverse effects ; Cytomegalovirus/drug effects ; Cytomegalovirus Infections/*drug therapy/*etiology/physiopathology ; *Encephalitis/etiology/pathology/virology ; Fatal Outcome ; Humans ; Male ; *Precursor Cell Lymphoblastic Leukemia-Lymphoma/complications/drug therapy/virology ; Transplantation Conditioning/methods