The use of umbilical cord blood in mismatched related and unrelated hemopoietic stem cell transplantation

Over the past 6 years, umbilical cord blood has emerged as an efficacious alternative source of hematopoietic stem cells in related bone marrow transplantation. These encouraging results led us to extend this technology to the mismatched related and unrelated settings in three high-risk leukemic children lacking a matched-related donor for transplantation. Two of the three children also lacked identifiable donors through the National Marrow Donor Program, while the third was in relapse and did not have time to wait for completion of a search. The first child was transplanted with haploidentical umbilical cord blood-derived mononuclear cells from his sister, while the remaining two children were transplanted with partially mismatched, unseparated, unrelated umbilical cord blood banked through the Placental Blood Project at the New York Blood Center. All three children demonstrated trilineage engraftment with donor cells within 6 weeks of transplantation. The patient transplanted with haploidentical marrow developed grade 2 graft vs. host disease (GVHD), which was controlled with steroid and anti-thymocyte globulin (ATG) therapy. One of the two patients grafted with unrelated umbilical cord blood developed mild grade 1 GVHD of the skin, which rapidly cleared with steroid therapy. One patient remains alive, in good health and disease-free 12 months from transplantation.     

Fulminant, CMV-associated, haemophagocytic syndrome following unrelated bone marrow transplantation

We report a case of haemophagocytic syndrome (HPS) occurring after allogeneic bone marrow transplantation (BMT) for acute promyelocytic leukaemia (APL) in a patient in fourth complete remission (CR). Anti-cytomegalovirus (CMV) antibody (Ab) was negative in this patient before BMT. BMT was performed from an HLA-identical unrelated donor who was positive for CMV Ab. After bone marrow engraftment and haematological recovery, severe acute graft-versus-host disease (GVHD) developed. This patient was treated with methylprednisolone in addition to cyclosporin A (CsA). Acute GVHD showed partial improvement, but CMV antigenaemia was observed. Despite administration of gancyclovir and immunoglobulin, CMV antigenaemia showed no improvement and HPS developed. As no other infections or malignancies were observed, we suspect that CMV infection was the trigger for development of HPS.     

A study of the changes during heating of paracetamol

Fanconi anaemia (FA) is an accepted indication for treatment with allogeneic HLA-identical BMT. Most patients, however, lack a suitable HLA-identical donor. In our centre, six FA patients were transplanted with a matched unrelated donor. Due to hypersensitivity to DNA cross-linking agents, a low-dose cyclophosphamide (CY) and thoraco-abdominal irradiation (TAI) regimen is recommended for conditioning in FA. We added Ara-C upfront and anti-T cell antibodies to enhance engraftment and to prevent GVHD, in combination with T cell depletion in four out of six of the first transplants. One patient did not engraft. In three patients rejection was observed. In three of these four patients a second BMT, using full bone marrow grafts, resulted in successful engraftment. The other patient died before a second BMT could be performed. The incidence and severity of acute GVHD was low: only one patient with grade III acute GVHD was seen. Two out of four surviving patients suffered from chronic GVHD. Four patients survived (median survival time 43 months after BMT), three with good and one with acceptable quality of life. Two patients died, one patient due to adenoviral reactivation with multi-organ failure, and one due to sepsis complicated by ARDS. In conclusion, MUD BMT is feasible in FA patients with bone marrow failure in whom no HLA-identical sibling donor is available. In our study group, the major problem was graft rejection, despite the administration of a combination of graft enhancing anti-T cell antibodies. Multicentre studies are needed to determine a more intensive, but still tolerable, conditioning regimen.     

Hematopoietic stem cell transplantation for infantile osteopetrosis

Infantile osteopetrosis is a lethal disorder resulting from a severe defect in the ability of osteoclasts to resorb bone. The only therapy shown to be capable of providing lasting benefit is allogeneic hematopoietic stem cell transplantation (HCT). We report the outcome of 10 patients with infantile malignant osteopetrosis treated with HCT from an HLA A, B, DRB1 matched (n=6) or A or B locus mismatched (n=4) family member or unrelated donor at the University of Minnesota between 1978 and 1997. Eight of 10 patients achieved primary engraftment; secondary graft failure was seen in two patients. Five of 10 patients survive; three with full or partial donor chimerism and two with autologous hematological recovery. Transient or partial donor chimerism can be sufficient to correct the hematological manifestations of osteopetrosis. We recommend early referral for consideration of HCT with a related or unrelated donor as neurosensory manifestations of osteopetrosis are generally not reversible. Donor engraftment may be easier to achieve early in the course of the disease.     

The heart as a self-regulating system: integration of homeodynamic mechanisms

Soluble interleukin-2 receptor (sIL-2R) levels were analyzed in the sera from 27 patients who underwent allogeneic bone marrow transplantation (BMT) in order to to examine whether there was any correlation between sIL-2R levels and graft-versus-host disease (GVHD). The sIL-2R levels markedly increased at the engraftment period, mainly due to cytokine administration shortly after BMT. Although the sIL-2R levels increased at the onset of acute GVHD, the subsequent development of GVHD could not be predicted by the sIL-2R levels documented before acute GVHD. As acute GVHD improved, the sIL-2R levels decreased, thus showing that the sIL-2R levels correlated with the disease status. In patients without acute GVHD, the sIL-2R levels gradually decreased with time and returned to the pretransplant levels after about 12 weeks post BMT. The sIL-2R levels were higher in unrelated allogeneic BMT patients with acute GVHD when compared with related allogeneic BMT patients. There was a significant increase in the sIL-2R levels at the engraftment period and at the onset of acute GVHD. At the onset of chronic GVHD, the sIL-2R levels once again increased and then decreased as chronic GVHD improved. Prolonged increase in sIL-2R levels was followed by subsequent development of chronic GVHD. Patients with a poor prognosis had higher sIL-2R levels than those with a good prognosis. Therefore, it seems that sIL-2R is a useful marker for monitoring the disease status of acute and chronic GVHD.     

Centurion syndrome. Idiopathic anterior displacement of the medial canthus

Bone marrow transplantation (BMT) using HLA-partially matched family donors has produced disappointing results (25-30% of long-term survivors) in patients with severe aplastic anemia. We describe two children affected by severe aplastic anemia, not responsive to immunosuppressive therapy, who underwent allogeneic bone marrow transplantation using a HLA-partially matched family donor. Both cases presented 2 first class HLA-antigens (A and B) disparity between donor and recipient. The pretransplant conditioning regimen consisted of cyclophosphamide, thoracoabdominal irradiation, cytosine-arabinoside, and antilymphocyte globulin. As graft versus host disease (GVHD) prophylaxis, Cyclosporine-A was administered at usual dosages for 6 months. A full marrow engraftment was observed in both cases. Only grade I acute GVHD, promptly responsive to corticosteroid therapy, developed with no chronic GVHD. Five months after transplant, both children progressively developed hypertension, renal function impairment, thrombocytopenia, and severe normochromic anemia, with erythropoietin serum levels lower than expected for the haematocrit. After antihypertension treatment and supportive therapy, the clinical picture progressively improved, while treatment with recombinant human erythropoietin completely corrected the long-lasting anemia. The two children are alive and well 28 months after the transplant, with a Karnofsky score of 100% and a normal peripheral blood count. The authors suggest that, once immunosuppressive therapy has failed, BMT from donors other than HLA-identical sibling is a feasible approach in children affected by severe aplastic anemia, not having an HLA-identical donor.     

Engraftment of unrelated donor stem cells in children with familial amegakaryocytic thrombocytopenia

Congenital amegakaryocytic thrombocytopenia is an extremely rare disorder for which bone marrow transplantation offers the only possibility for cure. The pathophysiology is unclear. Two children with familial amegakaryocytic thrombocytopenia underwent unrelated donor transplantation (bone marrow in one, umbilical cord blood in the second) after a preparative regimen of cyclophosphamide and total body irradiation. Both patients failed initial engraftment, required further donor stem cell infusions and are currently well with sustained engraftment, 16 months and 7 months after transplantation, respectively. The difficulty in achieving engraftment of unrelated donor stem cells in these children suggests that in future cases additional measures to achieve engraftment may be necessary, for example, a more aggressive preparative regimen or an increased stem cell dose.     

Engraftment of severe combined immune deficient mice receiving allogeneic bone marrow via In utero or postnatal transfer

Although in utero transplantation (IUT) has been shown to be effective in treating human severe combined immune deficiency (SCID), the relative merit of IUT as compared with postnatal bone marrow transplantation (BMT) for SCID is unknown. Therefore, comparative studies were undertaken in mice to determine the engraftment outcome in these two settings. Because T-cell depletion (TCD) reduces graft-versus-host disease (GVHD) severity but compromises alloengraftment, studies were performed with TCD or non-TCD BM and GVHD risk was assessed using a tissue scoring system and by the adoptive transfer of splenocytes from engrafted mice into secondary recipients. Non-SCID recipients received pre-BMT irradiation to simulate those circumstances in which conditioning is required for alloengraftment. IUT recipients of non-TCD and especially TCD BM cells in general had higher levels of donor T-cell and myeloid peripheral blood (PB) engraftment than nonconditioned SCID recipients. Increased TCD or non-TCD BM cell numbers in adult SCID recipients resulted in similar levels of PB engraftment as IUT recipients. However, under these conditions, mean GVHD scores were higher than in IUT recipients. The majority of adoptive transfer recipients of splenocytes from IUT recipients were GVHD-free, consistent with the in vitro evidence of tolerance to host alloantigens. Total body irradiation (TBI)-treated mice that had the highest engraftment had evidence of thymic damage as denoted by a higher proportion of thymic and splenic T cells with a memory phenotype as compared with IUT recipients. IUT mice had vigorous thymic reconstitution by 3 weeks of age. Our data indicate that IUT has a number of advantages as compared with postnatal BMT. Future studies examining the fine specificity of immunoreconstitution in IUT versus postnatal BMT are indicated.     

In vivo infusion of anti-LFA-1 and anti-CD2 antibodies prevents graft failure after HLA partially incompatible bone marrow transplantation in children with high risk acute lymphoblastic leukaemia

Bone marrow transplantation (BMT) from matched sibling donors is the therapy of choice for children with high-risk acute lymphoblastic leukaemia in children. It is however not available to more than two-thirds of patients who lack a matched donor. Here, we review the outcome of 28 patients with high-risk ALL who were transplanted in France with alternative marrow sources such as HLA-phenoidentical unrelated volunteers and HLA-partially incompatible relatives. For these patients, we tested the possibility to prevent T-depleted marrow graft rejection by infusing in vivo two monoclonal antibodies directed against adhesion receptors i.e., LFA-1 and CD2. Two previous multicenter trials in children transplanted with partially incompatible bone marrow for inborn errors of metabolism showed their efficacy in this setting. Twenty eight patients were enrolled in this study and followed for a median of 4.4 years. Bone marrow engraftment occurred in 81% of the evaluable patients. Post-transplantation leukaemic relapse was the most frequent cause of death in this group of patients, and occurred in 39% of patients. The second most frequent complication was infectious disease, while an EBV-induced B-lymphocyte proliferative disorder occurred in four patients. In conclusion, T-cell-depletion combined with infusion of anti-LFA-1 and anti-CD2 antibodies is efficient in preventing graft failure and GVHD in this group of children with high-risk leukaemia undergoing partially incompatible BMT. The overall DFS is not improved in contrast to what has been previously observed in patients with immunodeficiencies transplanted with a similar rejection prophylaxis. Other approaches are therefore needed aiming either at preserving donor T-cell mediated immunity or accelerating immune reconstitution.     

Unrelated donor bone marrow transplantation for children with acute leukemia

PURPOSE: To test the use of unrelated donor bone marrow transplantation (URD BMT) to cure children with high-risk acute leukemias. PATIENTS AND METHODS: Between June 1985 and December 1994, 50 children with acute leukemia (15 acute myelogenous leukemia [AML], 35 acute lymphoblastic leukemia [ALL]; 22 greater than second complete remission [CR]) received BMT from a URD at the University of Minnesota. Ages ranged from 0.9 to 17.5 years (median, 8.8). Median follow-up is 2.1 years (range, 1 to 7.3). Thirty patients (60%) received bone marrow fully matched at HLA-A,B and DRB1; 20 (40%) received bone marrow with a major or minor mismatch at a single HLA-A or B locus. RESULTS: The median time to neutrophil engraftment was day 24 (range, 14 to 42 days) in those receiving matched and day 25 (range, 15 to 32 days) in those receiving mismatched marrow (P = .35). The incidence of grades III to IV graft-versus-host disease (GVHD) was 23% (95% confidence interval [CI], 7% to 39%) in matched and 32% (95% CI, 8% to 52%) in HLA-mismatched patients (P = .57). The incidence of chronic GVHD was 50% (95% CI, 28% to 72%) in matched and 57% (95% CI, 23% to 91%) in mismatched patients (P = .80). Disease-free survival for patients with ALL is 37% (95% CI, 21% to 53%) at 1 year and 30% (95% CI, 15% to 46%) at 2 years; for patients with AML, 53% (95% CI, 28% to 78%) at 1 year and 33% (95% CI, 6% to 60%) at 2 years. CONCLUSION: URD BMT is an effective treatment for children with poor-prognosis acute leukemia and should be considered for all high-risk patients. Early referral of patients is strongly recommended.     

Ethopharmacological analysis of naloxone-precipitated morphine withdrawal syndrome in rats: a newly-developed "etho-score"

We report a retrospective analysis of the experience of a single centre in treating severe aplastic anemia (SAA) with allogeneic bone marrow transplant (BMT). Between 1982 and 1992, we transplanted 21 patients with SAA (14 males, 7 females); median age at BMT was 15 y (range 2-40 y); median time from diagnosis of SAA to BMT was 29 d (range 6 d-5.5 y). Thirteen patients had received multiple transfusions before BMT. Patients were conditioned with cyclophosphamide 50 mg/kg for 4 d, +/- total body irradiation 300-500 cGy as a single fraction; 1 patient received total nodal irradiation (750 cGy) plus antithymocyte globulin. Sixteen patients received bone marrow from human leucocyte antigen (HLA)-identical siblings, 3 from haplo-identical parents, and 2 from unrelated volunteer donors; graft-versus-host disease (GVHD) prophylaxis was variable. Three patients failed to fully engraft following BMT; 2 achieved successful engraftment following a second BMT. Six of 20 evaluable patients (30%) developed grade II-IV acute GVHD, of whom 3 died; 3 patients developed limited and 5 patients (31%) developed extensive chronic GVHD, of whom 1 died. Fourteen patients (67%) are alive and well following BMT with a median follow-up of 6 y (range 2.1-11 y). Survival was superior in patients receiving sibling-donor BMT (75%) compared with those receiving parent- or unrelated-donor BMT (40%). We conclude that allogeneic BMT remains an important mode of treatment for SAA, but long-term survival remains limited by graft failure and GVHD.     

Stem cells from bone marrow, umbilical cord blood and peripheral blood for clinical application: current status and future application

Bone marrow transplantation (BMT) has progressed rapidly during the past two decades to that of a treatment of choice as a therapeutically effective modality for the treatment of selected patients with malignant disease and non-malignant hematological disorders. However, its use is limited by availability of human leukocyte antigens (HLA)-matched donor cells, engraftment and graft-versus-host disease (GVHD). Prevention of GVHD, improvement in the speed and quality of marrow reconstitution, and screening of new immunomodulating agents which improve engraftment and augment hemopoiesis are intense areas of investigation. To this end there has clearly been progress in purification and characterization of human stem cells from different tissue sources. Discussed in this review are: (a) stem cell purification, characterization and ex vivo expansion; (b) bone marrow stem cell transplantation; (c) cord blood stem cell transplantation; (d) peripheral blood stem cell transplantation; (e) fetal liver stem cell transplantation; (f) in utero stem cell transplantation; and (g) evaluation of the capacity of stem cells to serve as targets for gene therapy.     

Efficacy and costs of granulocyte colony-stimulating factor in allogeneic T-cell depleted bone marrow transplantation

Hematopoietic growth factors have shown clinical benefits in patients undergoing chemotherapy and stem cell transplantation, but few studies have been performed to assess whether the benefits are worth the costs. We reviewed 196 patients undergoing T-cell depleted related donor bone marrow transplantation (BMT) between 1990 and 1996 to assess the effect of growth factor use on time to engraftment and costs of hospitalization. Beginning in 1994, based on encouraging results in autologous transplantation, patients (n = 81) were treated with granulocyte colony-stimulating factor (G-CSF) starting at day +1 after marrow infusion until engraftment. Between January 1, 1990 and January 1, 1994, patients (n = 115) did not receive growth factor. CD6 depletion of donor marrow was the only form of prophylaxis against graft-versus-host disease (GVHD). Despite receiving a lower stem cell dose (P = .004), the group receiving G-CSF had a decreased time to engraftment (20 days v 12 days, P < .0001) and time from marrow infusion to discharge (23 days v 17 days, P < .0001). In multivariate modeling, the use of G-CSF was the most significant factor predicting time to engraftment and discharge. Incidence of grades II-IV GVHD, early mortality, percentage of patients who engrafted, and relapse rates did not differ between the groups. Inpatient charges during the first 50 days after marrow infusion (including readmissions) were available on 110 patients and were converted to costs using departmental ratios of costs of charges. Median costs were significantly lower in the group receiving G-CSF ($80,600 v $84,000, P = .0373). Thus, use of G-CSF in this setting allows earlier hospital discharge with lower costs.     

Host reactive donor T cells are associated with lung injury after experimental allogeneic bone marrow transplantation

Noninfectious lung injury is common after allogeneic bone marrow transplantation (BMT), but its association with acute graft-versus-host disease (GVHD) is unclear. Using a murine BMT system where donor and host differ by multiple minor histocompatibility (H) antigens, we investigated the nature of lung injury and its relationship both to systemic GVHD and host-reactive donor T cells. Lethally irradiated CBA hosts received syngeneic BMT or allogeneic (B10.BR) T-cell-depleted (TCD) bone marrow (BM) with and without the addition of T cells. Six weeks after BMT, significant pulmonary histopathology was observed in animals receiving allogeneic BMT compared with syngeneic controls. Lung damage was greater in mice that received allogeneic T cells and developed GVHD, but it was also detectable after TCD BMT when signs of clinical and histologic acute GVHD were absent. In each setting, lung injury was associated with significant alterations in pulmonary function. Mature, donor (Vbeta6(+) and Vbeta3(+)) T cells were significantly increased in the broncho-alveolar lavage (BAL) fluid of all allogeneic BMT recipients compared with syngeneic controls, and these cells proliferated and produced interferon-gamma (IFN-gamma) to host antigens in vitro. These in vitro responses correlated with increased IFN-gamma and tumor necrosis factor-alpha (TNF-alpha) in the BAL fluid. We conclude that alloreactive donor lymphocytes are associated with lung injury in this allogeneic BMT model. The expansion of these cells in the BAL fluid and their ability to respond to host antigens even when systemic tolerance has been established (ie, the absence of clinical GVHD) suggest that the lung may serve as a sanctuary site for these host reactive donor T cells. These findings may have important implications with regard to the evaluation and treatment of pulmonary dysfunction after allogeneic BMT even when clinical GVHD is absent.     

Bone marrow transplantation in primary immunodeficiency syndrome and in osteopetrosis

The designation primary immunodeficiency embraces a multiplicity of diseases of which only the more severe constitute indications for BMT (bone marrow transplantation)--e.g. severe combined immunodeficiency (SCID), Wiskott-Aldrich syndrome, familial haemophagocytic lymphohistiocytosis and malignant osteopetrosis. In cases of immunodeficiency, the outcome of BMT is strongly dependent on the patient's age, clinical status at transplantation and the type of immunodeficiency. In children with SCID who undergo BMT during the first few months of life, lasting cures can be obtained in almost 100 percent of the cases, whereas there is only a 15 percent probability of success if the child is older, infected, cannot undergo cytostatic preconditioning or cannot be given T-cell depleted bone marrow.     

Outcomes of recipients of both bone marrow and solid organ transplants. A review

In this review we examine the clinical outcomes of patients who have received both bone marrow transplantation (BMT) and solid organ transplantation (SOT) and discuss the possible immunologic consequences of the dual transplants. We collected cases through a comprehensive literature search (MEDLINE database, English literature only) covering the years 1990 through 1997 and correspondence with the International Bone Marrow Transplant Registry. Our study selected case reports of patients who have undergone both bone marrow and solid organ transplants; cases in which bone marrow transplantation was undertaken as an adjunct ot induce or augment donor-specific tolerance in a recipient to the transplanted organ were excluded. Clinical characteristics included patient's demographic information, underlying disorders for each transplant, source of donor organ or tissue, time between transplants, and immunosuppressive regimens used to prevent graft-versus-host disease (GVHD) or graft rejection. Clinical outcomes included patient survival, complications of transplantation, and donor-specific tolerance that was experienced in many cases. Twenty-one cases of SOT after BMT and 7 cases of BMT after SOT were reviewed. Solid organ transplantations included lung, liver, cardiac, and kidney for a variety of BMT-related complications including GVHD, hepatic veno-occlusive disease, chronic renal failure, end-stage pulmonary disease, and severe cardiomyopathy. Bone marrow transplants were performed following SOT for aplastic anemia and hematologic malignancies. Clinical outcomes for patients who received both BMT and SOT were variable and depended on transplant indication and degree of histocompatibility. Prior bone marrow transplantation may tolerize for a subsequent organ transplant from the same donor. Conversely, severe GVHD may follow BMT from human leukocyte antigen (HLA)-matched donors following SOT. The favorable survival in this high-risk group of patients may represent a literature review bias (that is, an undetermined number of unsuccessful cases may not have been reported). Nonetheless, dual transplantation is clearly feasible in selected cases.     

Relative risk and excess rate models in exposure-response analysis

To date, in utero bone marrow transplantation (BMT) has had limited success, largely because of poor donor engraftment. The poor engraftment is probably the result of performing the procedure late in gestation after significant fetal immunocompetence has developed and/or transplanting insufficient numbers of donor hematopoietic stem cells for competing successfully with ongoing fetal hematopoiesis. To overcome these problems, we performed in utero BMT on a fetus with globoid cell leukodystrophy during the first trimester of gestation using selected paternal bone marrow stem (CD34+) cells. CD34 selection allowed a substantially greater number of stem cells to be transplanted. Although the fetus died 7 weeks after the procedure (during the 20th week of gestation), full donor engraftment was established. Moreover, the cause of death appeared to be overwhelming donor engraftment and leukostasis with paternal myeloid cells infiltrating most tissues. The ability of in utero BMT to produce this degree of engraftment provides great promise for the use of this approach in the treatment of a variety of inherited disorders that can be diagnosed prenatally.     

Methylsulfonyl metabolites of PCBs and DDE in human tissues

More than 15 years passed since bone marrow transplantation (BMT) have first introduced to the field of treatment of pediatric cancer. During this period, technology and modality of BMT have been improved steadily and several kinds of hemopoietic stem cell transplantation, for instance, allogeneic BMT from related or unrelated donor, unpurged or purged autologous BMT by 4-hydroperoxycyclophosphamide (4-HC) or magnetic immuno-beads, allogeneic or autologous peripheral blood stem cell transplantation and cord blood stem cell transplantation became available. Now we can choose the most suitable transplantation method for each patient from our repertory according to the patient's condition. In this article, treatment result of allogeneic BMT and 4-HC purged autologous BMT for children with acute leukemia and several kinds of hematopoietic stem cell transplantation for children with solid tumors in my hospital were reported.     

Changes in lung and chest wall properties with abdominal insufflation of carbon dioxide are immediately reversible

There is increasing interest in blood cell transplants (BCT) from normal donors as an alternative to BMT. Ten patients with relapsed or persistent leukemia after BMT received intensive cytotoxic conditioning followed by allogeneic BCT. Three BCT were from single-antigen mismatched donors; two of the corresponding recipients had rejected a BMT from the same donor. Two patients received BCT from a different donor (one matched, one single-antigen mismatched). The other six BCT were from the same, fully matched, bone marrow donors. Donors were given G-CSF to mobilize progenitor cells which were collected by a single 2-4 h leukapheresis. Methotrexate, CsA and folinic acid were used for GVHD prophylaxis for all transplants but CsA was discontinued sooner after BCT than after BMT. One patient died without engraftment having rejected a BMT from the same single-antigen mismatched donor 4 years previously. Nine patients had granulocyte recovery at a median of 14 days, up to 6 days faster than with their previous BMT. Platelet recovery was also 2-6 days faster than with BMT in four previously engrafting patients. Four patients died without platelet recovery after BCT within a year of BMT, three of treatment-related toxicity and one of relapse. Two patients developed grade II acute GVHD. Of six patients given BCT more than a year from BMT, four, all with acute leukemia, survive 7, 14, 29 and 29 months after BCT and one relapsed at 7 months. All four survivors developed chronic GVHD. These results indicate that BCT may be useful therapy for relapse occurring more than a year after BMT.     

Donor lymphocyte infusion for the treatment of relapse after allogeneic hematopoietic stem cell transplantation

The results of donor lymphocyte infusion (DLI) for treatment of relapse after bone marrow transplantation (BMT) are reviewed. Durable complete remission can be achieved at the molecular level for a majority (more than 70%) of patients with CML, when treated at early relapse. Results are less favourable for acute leukemias, although useful responses have been reported. Data are scarce though promising for myelodysplastic syndromes and multiple myeloma. Major treatment-associated toxicities are GVHD and bone marrow aplasia. The latter complication can be predicted by evaluating the level of residual donor-derived hematopoiesis. Modification of infused cells (CD8 negative selection or transduction with a suicide gene), addition of peripheral blood stem cells, and early implementation of escalating doses may counteract the complications and increase the response rate. Response rate is variably influenced by the presence of chronic GVHD after initial BMT, T-cell depleted BMT, underlying disease and stage at relapse, and the level of mixed chimerism. DLI is a direct demonstration of the graft-versus-leukemia effect (GVL). Because GVL after BMT is sometimes the predominant cause of cure, it may be advisable in such situations to redirect the conditioning regimens for BMT towards engraftment and less immediate cytotoxicity.