Isabel Sanjuan

Unrelated umbilical cord blood transplants in adults: Early recoveryof neutrophils by supportive co-transplantation of a low number of highlypurified peripheral blood CD34+ cells from an HLA-haploidentical donor

UNLABELLEDnOBJECTIVE, METHODS, AND RESULTS: To reduce the period of posttransplant neutropenia and related early morbidity and mortality of cord blood (CB) transplants, we assessed the feasibility of co-infusion of a low number of highly purified peripheral blood CD34+ cells from a related haploidentical donor with a CB graft. Between March 1999 and May 2002, 11 patients with high-risk hematologic malignancies were transplanted using this strategy. The seven patients who received a haploidentical peripheral blood graft and a CB graft from a sibling (6) or the father (1) had prompt recovery (9-17 days, median 10) of the absolute neutrophil count (ANC) to greater than 0.5 x 10(9)/L. Analysis of DNA polymorphisms showed initial predominance of the haploidentical genotype both in granulocytes and in mononuclear cells, and subsequent progressive replacement by cells of CB genotype until final complete CB chimerism was achieved by patients who survived for sufficient periods of time. The four patients who received maternal haploidentical cells had no significant contribution of these to blood leukocytes, although complete CB chimerism was achieved by three of them and two reached engraftment of the CB on days +20 and +36. Morbidity due to early bacterial or fungal infections was remarkably low in patients with prompt ANC recovery.nnnCONCLUSIONnOur data show that co-infusion of a CB unit and a low number of haploidentical CD34+ cells may result in a shortened period of posttransplant neutropenia. This is likely the result of prompt and transient engraftment of the haploidentical hematopoietic stem cells that may provide the patient antimicrobial protection until the later engraftment of the CB hematopoietic stem cells.

Results of a pilot study on the use of third-party donor mesenchymal stromal cells in cord blood transplantation in adults

BACKGROUND AIMSnCord blood (CB) transplants with co-infusion of third-party donor (TPD) mobilized hematopoietic stem cells (MHSC) have been shown to result in bridge engraftment with prompt neutrophil recovery and high final rates of CB engraftment and full chimerism. This strategy overcomes the limitation posed by low cellularity of CB units for unrelated transplants in adults. Enhancement of adaptive immunity reconstitution without increasing risks of graft-versus-host disease (GvHD) is required to optimize results further. Our objectives were to evaluate co-infusion of mesenchymal stromal cells (MSC) from the same TPD regarding tolerance, CB engraftment and effects on acute (a)GvHD, both preventive and therapeutic.nnnMETHODSnEx vivo-expanded bone marrow MSC were infused at the time of the transplant or the in case of refractory aGvHD.nnnRESULTSnNine patients received 1.04 - 2.15 x 10(6)/kg (median 1.20) MSC immediately after CB and TPD MHSC. Neither immediate adverse side-effects nor significant differences regarding CB engraftment or aGvHD development were observed. Four patients developed grade II aGvHD, refractory to steroids in two. These reached complete remission after therapeutic infusions of MSC.nnnCONCLUSIONSnIn recipients of dual CB/TPD MHSC transplants, MSC infusions were therapeutically effective for severe aGvHD but no significant differences in CB engraftment and incidence of severe aGvHD were observed following their prophylactic use. Although results of this study alone cannot conclusively determine the application of MSC in CB transplantation, we believe that, in this setting, the best use of MSC could be as pre-emptive treatment for aGvHD.

Cord blood transplants: early recovery of neutrophils from co-transplanted sibling haploidentical progenitor cells and lack of engraftment of cultured cord blood cells, as ascertained by analysis of DNA polymorphisms

The number of infused cells is a very important factor in cord blood transplant (CBT) engraftment. Prior ex vivo expansion of aliquots of transplanted cord blood (CB) units is being investigated as a procedure to increase engraftment potential, but results are difficult to evaluate due to a lack of markers for assessing the contribution of expanded cells. We transplanted five patients, infusing the best available CB unit and cells from a second donor simultaneously. In two patients, these cells were obtained from another frozen CB unit by CD34+positive selection and culture expansion; the other three patients received uncultured highly purified haploidentical CD34+ cells. The first two patients had DNA from the culture expanded CB cells detected only for a few days around day +11 when the absolute neutrophil count (ANC) was >200/μl; thereafter and when the ANC was <500/μl, only donor DNA from the uncultured CB was detected. For the other three patients, DNA analysis showed early and transient granulocyte engraftment of haploidentical cells, progressively replaced by the CB-derived granulocytes. We concluded that: (1) simultaneous infusion of lymphocyte-depleted HLA highly mismatched haematopoietic progenitor cells has not produced unfavourable effects for CBT; (2) the double transplant model is suitable for evaluating the engraftment potential of ex vivocultured CB cells in the clinical setting; (3) the culture conditions used did not result in early recovery of ANC; and (4) co-transplantation of purified uncultured HLA haploidentical CD34+ cells may reduce the time of neutropenia following CBT.Bone Marrow Transplantation (2001) 28, 355–363.

Chagas disease in a recipient of cord blood transplantation.

American trypanosomiasis, or Chagas disease, is caused by a protozoan, Trypanosoma cruzi. It is endemic in Latin America where it represents a major public health problem. Chagas disease also occurs in non-endemic areas where it can be acquired by blood transfusion, congenital transmission and organ transplantation. The disease can be fatal in immunosuppressed patients.1 We report a case of reactivation of Chagas disease (acute form) in a patient who underwent cord blood transplantation in a non-endemic European country.

Epstein-Barr virus associated B-cell lymphoma after autologous bone marrow transplantation for T-cell acute lymphoblastic leukaemia

Epstein‐Barr virus associated lymphoproliferative disease after autologous bone marrow transplantation (ABMT) has rarely been reported. We report a case of B‐cell lymphoma following ABMT for T‐acute lymphoblastic leukaemia; bone marrow was purged in vitro with monoclonal antibodies to remove T cells. Immunoglobulin and T‐cell receptor gene rearrangement studies were used to demonstrate clonality and to show that this patient developed a second neoplasm after ABMT. EBV proteins and genome (type A) were present in post‐transplantation lymphoma, suggesting a causative role in its development.

Diagnosis of transfusion‐associated graft‐versus‐host disease by polymerase chain reaction in fludarabine‐treated B‐chronic lymphocytic leukaemia

Summary. Transfusion‐associated graft‐versus‐host disease (TA‐GVHD), has rarely been reported associated with B‐chronic lymphocytic leukaemia (B‐CLL). We report a patient diagnosed with B‐CLL, previously treated with fludarabine, who developed TA‐GVHD after being transfused during surgery for splenectomy. Diagnosis was confirmed by polymerase chain reaction (PCR) detection of donor DNA in the patient, by amplification of Y‐chromosome sequence and analysis of minisatellite polymorphisms. B‐CLL patients treated with fludarabine appear to be at risk for TA‐GVHD and should be regarded as candidates for transfusions with irradiated blood products. This case illustrates that PCR is a rapid technique for the early diagnosis of TA‐GVHD.

Infusion of lymphocytes obtained from a donor immunised with the paraprotein idiotype as a treatment in a relapsed myeloma

A 48-year-old patient with IgA k multiple myeloma received a BMT from his HLA-matched sibling. After transplantation, the disease relapsed. Melphalan therapy followed by reinfusion of haemopoietic blood stem cells collected from the patient led to the improvement of the clinical status, although mixed chimerism and an elevated serum IgA persisted. Successful donor immunisation against an immunogenic preparation of the recipient monoclonal protein was performed before the infusion of donor T lymphocytes (DLI) into the patient. Ten weeks after the lymphocyte infusions, no monoclonal band was evidenced and donor complete chimerism was detected. The patient did not develop GVHD. Once complete remission was achieved, the idiotype vaccine was administered to the patient. Nineteen months after DLI, the patient remains in remission. Bone Marrow Transplantation (2000) 25, 1105–1108.

Management of thrombotic microangiopathy following allogeneic transplantation: what is the role of plasma exchange?

Thrombotic microangiopathy (TMA) is an infrequent but serious complication of allogeneic transplantation. The success rate of plasma exchange (PE) reported in the treatment of this entity is a controversial subject. We report the outcome of 10 patients with TMA post-allogeneic transplantation after treatment with PE. Two out of the 10 patients have not responded, five had a partial response, but died of acute GVHD or interstitial pneumonitis, and three have responded and recovered. Our study suggests that there are different degrees of TMA severity. Only mild multifactorial cases with no severe hemolysis (LDH activity <1000 u/l) may be fully resolved with pe.

Immune reconstitution after cord blood transplants supported by coinfusion of mobilized hematopoietic stem cells from a third party donor.

Low severity of GVHD, substantial graft vs tumor (GVT) and slow development of protective immunity are well-documented features of cord blood transplants (CBT). We have evaluated the immune reconstitution of adult recipients of single-unit CBT supported by the coinfusion of third party donor (TPD) mobilized hematopoietic stem cells (MHSC), a procedure—‘dual CB/TPD-MHSC transplant’—that results in early recovery of circulating granulocytes, high rates of CB engraftment and full chimerism. Cumulative recovery of natural killer and B cells at or above the median values of normal controls were 1.0 and 0.76 by the sixth and ninth months. Recovery of T cells was much slower, naive cells lagging behind those of memory and effector (committed) immunophenotypes. Serial analyses of signal joint TCR excision circles showed a general pattern of very low levels by the third month after CBT, followed by recovery to levels persistently similar or higher than those observed before transplantation and in normal controls. Our results are consistent with the clinical observations of substantial GVT effect together with low incidence of serious GVHD and slow development of protective immunity and suggest that thymic function contributes substantially to the recovery of T-cell populations in adults receiving dual CB/TPD-MHSC transplants.