Role of factor VIII on activated protein C resistance ratio in inflammatory diseases

Therapeutic options for treatment of recurrence of leukaemia after allogeneic bone marrow transplantation (BMT) are limited. A beneficial effect of donor lymphocyte infusions (DLI) has not previously been described in acute myeloid leukaemia (AML) relapse. We report a case of AML with t(8;21), relapsing 3 months after BMT, who received DLI without adjuvant chemotherapy or growth factors. The patient developed acute GVHD and achieved a rapid complete remission of his AML by both cytologic and molecular criteria of at least 14 months duration, thereby showing that DLI for AML in relapse after BMT is an alternative therapeutic option.     

Donor lymphocyte infusion for childhood acute lymphoblastic leukaemia relapsing after bone marrow transplantation

Four children with acute lymphoblastic leukaemia (ALL) who relapsed after allogeneic bone marrow transplantation (BMT) were treated with donor lymphocyte infusion (DLI) without prior conditioning. Three patients had previously received a non-T-cell-depleted matched sibling BMT and the fourth had a T-cell-depleted matched unrelated BMT. Two patients developed grade III–IV acute graft-versus-host-disease (GVHD) of the skin, which required intervention. Both are alive in complete haematological remission 7 and 10 months from DLI with chronic GVHD of the skin requiring immunosuppressive therapy. A third patient went into haematological remission 6 weeks after DLI, but with no clinical evidence of GVHD. His bone marrow remained in remission 11 months post-DLI despite the disease (ALL) relapsing in extramedullary sites. The fourth patient showed no clinical or haematological response to three consecutive doses of DLI given at 4-weekly intervals and died from progressive disease 11 months after relapse. These preliminary observations indicate that in constrast to experience in adult ALL, DLI may be effective in inducing sustained remission in children with ALL relapsing after BMT, and a response may occur even in the absence of clinical evidence of GVHD.     

Prophylactic donor lymphocyte infusions after moderately ablative chemotherapy and stem cell transplantation for hematological malignancies: high remission rate among poor prognosis patients at the expense of graft-versus-host disease

We investigated the use of 'prophylactic' donor lymphocyte infusions (DLI) containing 1 x 107 CD3+ cells, given at 30, 60 and 90 days post-allogeneic blood and marrow transplantation (BMT), following conditioning with fludarabine 30 mg/m(2)/4 days and melphalan 70 mg/m(2)/2 days. GVHD prophylaxis consisted of cyclosporin A (CsA) 2 mg/kg daily with early tapering by day 60. Our goals were the rapid achievement of chimerism and disease control, providing an immunological platform for DLIs to treat refractory patients with hematological malignancies. Twelve heavily pre-treated patients with life expectancy less than 6 months were studied; none were in remission. Diagnoses were AML (n = 4), MDS (n = 1), ALL (n = 3), CML (n = 3) and multiple myeloma (n = 1). Response rate was 75%. Three patients are alive at a median of 450 days (range, 450-540). Two patients are in remission of CML in blast crisis and AML for more than 14 months. Median survival is 116 days (range, 25-648). Six patients received 12 DLIs; three patients developed acute GVHD after the first infusion and were excluded from further DLIs, but no GVHD occurred among patients receiving subsequent DLIs. One patient with CML in blast crisis went into CR after the first DLI. The overall incidence of acute GVHD was 70%. Primary causes of death were infections (n = 3), acute GVHD (n = 3), chronic GVHD (n = 1) and disease relapse (n = 2). We observed high response and chimerism rates at the expense of an excessive incidence of GVHD. DLI given at day +30 post BMT caused GVHD in 50% of the patients, and its role in this setting remains unclear.     

Treatment of relapse after allogeneic bone marrow transplantation with reduced intensity conditioning (FLAG ± Ida) and second allogeneic stem cell transplant

Acute leukaemias in relapse after allogeneic stem cell transplantation (SCT) respond poorly to donor leucocyte infusions (DLI) compared with chronic myeloid leukaemia (CML), at least in part because of faster disease kinetics. Fludarabine-containing 'non-myeloablative' chemotherapy followed by further allo SCT may offer more rapid and effective disease control. We report 14 patients with relapse after allo SCT for acute leukaemia [seven acute myeloid leukaemia (AML), five acute lymphoblastic leukaemia (ALL)] or refractory anaemia with excess blasts in transformation (RAEB-t, n = 2) treated with fludarabine, high-dose cytosine arabinoside (ara-C) and granulocyte colony-simulating factor (G-CSF) with (n = 10) or without (n = 2) idarubicin (FLAG +/- Ida) or DaunoXome (FLAG-X) (n = 2) and second allo SCT from the original donor. Donors were fully human leucocyte antigen (HLA) -matched in 13 cases with a single class A mismatch in one. Actuarial overall survival was 60% and disease-free survival was 26% at 58 months. Remissions after the second SCT were longer than those after the first bone marrow transplantation (BMT) in eight of the 13 assessable patients to date. Haematopoietic recovery was rapid. Transplants were well tolerated with no treatment-related deaths. The major complication was graft-versus-host disease (GvHD, acute >/= grade II-2 cases, chronic - eight cases, two limited, six extensive) although there have been no deaths attributable to this. FLAG +/- Ida and second allo SCT is a safe and useful approach and may be more effective than DLI in the treatment of acute leukaemias relapsing after conventional allo SCT.     

Donor leukocyte infusion for Japanese patients with relapsed leukemia after allogeneic bone marrow transplantation: lower incidence of acute graft-versus-host disease and improved outcome

To clarify the role of donor leukocyte infusion (DLI) in the treatment of leukemia relapsing after allo-BMT, data from 100 patients were collected from 46 facilities in Japan and analyzed with respect to the efficacy and adverse effects of donor leukocyte infusion. Complete remission was achieved in 11 of 12 (91%) patients with relapsed chronic myelogenous leukemia (CML) in chronic phase, three of 11 (27%) with CML in the acute phase, eight of 21 (38%) with acute myelogenous leukemia (AML), six of 23 (25%) with acute lymphoblastic leukemia (ALL) and five of 11 (45%) with myelodysplastic syndrome (MDS). The probability of remaining in CR at 3 years was 82% in CML patients in the chronic phase, but 0% in those with CML in the acute phase, 7% in those with AML, 0% with ALL and 33% with MDS. Acute GVHD (>/=2) developed in 31 of 89 (34%) patients with HLA-identical related donors and was fatal for seven (7%). Cytopenia developed in 21 of 94 (22%) with no associated fatalities. When the outcome of patients with CML in CP and MDS was analyzed, development of GVHD, cytopenia, or both, was associated with a higher GVL effect (15 of 16, 93%) than in those without adverse affects (one of 6, 17%). A leukocyte dose of 5 x 107/kg of recipient body weight appeared to be optimal as an initial dose of DLI. Given the relatively low incidence of acute GVHD and the similar GVL effect, DLI may be more beneficial to patients in Japan with recurrent leukemia than to those in Western countries. Bone Marrow Transplantation (2000) 26, 769-774.     

AUTOTRANSPLANTS IN ACUTE LEUKAEMIA

The data we review indicate that in adults with ALL in first remission intensive chemotherapy and radiation given before a transplant is more effective in eradicating leukaemia than current chemotherapy. This is not so in adults with AML in first remission where more intensive therapy does not reduce the likelihood of relapse. Furthermore, leukaemia relapse because of re-infused leukaemia cells is an important issue in autotransplants for ALL. Whether re-infusing leukaemia cells would be important in AML were more effective pretransplant therapy developed is unknown. Presently, there appears to be little sense to test in vitro approaches to remove leukaemia cells in autotransplants for AML because efficacy cannot be evaluated. (A randomized trial is an exception but would not be expected to show a difference.) Another conclusion is that attempts to induce GVHD in autotransplant recipients, such as by using cyclosporine post-transplant (Jones et al, 1989), are more likely to succeed in AML than ALL since the impact of GVHD is substantially greater (Horowitz et al, 1990). However, the GVHD-related antileukaemia effect in AML is associated with chronic GVHD whereas cyclosporine treatment of autotransplant recipients results in acute GVHD. Also, attempts to separate clinical and antileukaemia effects of GVHD were unsuccessful (Sullivan et al, 1989). Another caution is that in AML we detected an immune antileukaemia effect distinct from GVHD (termed GVL) only after HLA-identical sibling transplants. Since GVL was absent in twins it is unlikely to operate after autotransplants. In summary, there is sense in studying autotransplants in adults with acute leukaemia in first remission. However, there are currently no convincing data that autotransplants are superior to current therapy. More intensive treatment seems effective in ALL; the focus should be on increasing the antileukaemia efficacy of pretransplant therapy and on attempts to remove leukaemia cells from the graft. In AML, there is no evidence that more intensive therapy is more effective. This problem needs resolution before evaluating attempts to remove leukaemia cells from the graft. The best place to test new pretransplant regimens is in twins and recipients of HLA-identical sibling transplants without GVHD. The data and ideas we review and discuss should be useful in planning clinical trials.     

Effect of induced GVHD in leukemia patients relapsing after allogeneic bone marrow transplantation: single-center experience of 33 adult patients.

In a retrospective single center study, we examined the outcome of induced GVHD in leukemia patients relapsing after allogeneic BMT. Thirty-three adult patients with leukemia (15 AML, 3 ALL, and 15 CML) persisting or relapsing 1-36 months (median, 6) after allogeneic BMT underwent various immune manipulations and consequently developed acute and/or chronic GVHD at our center. Immunotherapies to elicit GVHD comprised chemotherapy followed by PBSC (n = 18), non-myeloablative transplant (n = 2), PBL followed by IFN-alpha (n = 5), PBL alone (n = 3), abrupt cessation of CsA (n = 3), and CsA withdrawal combined with IFN-alpha (n = 2). Twenty-four (72.7%) patients obtained a remission including complete hematological or cytogenetic remission, respectively, for acute leukemias or CML. Overall survival of patients, estimated at 3 years using the Kaplan-Meier method, was 33.9% (95% CI, 20-52%). Twelve patients including two patients with ALL remain in complete hematological (n = 5) or cytogenetic remission (n = 7) 3-93 months (median 12) after achieving remission. Twelve (63.2%) of 19 dead patients died due to treatment-related toxicities; five patients from acute GVHD, three from GVHD followed by infections and four from infections. By multivariate Cox analysis, only chronic GVHD resulted in a higher probability of disease-free survival (P = 0.026). Eight patients who had both acute GVHD < or = grade I and chronic GVHD are all alive without leukemia. We conclude that acute GVHD is associated with considerable toxicity while chronic GVHD plays a role in retaining remission in leukemia relapsing after allogeneic BMT.     

Treatment of relapsed leukemia after unrelated donor marrow transplantation with unrelated donor leukocyte infusions

The efficacy and toxicity of donor leukocyte infusions (DLI) after unrelated donor bone marrow transplantation (BMT) is largely unknown. We identified 58 recipients of unrelated DLI (UDLI) for the treatment of relapsed disease from the National Marrow Donor Program database. A retrospective analysis was performed to determine response, toxicity, and survival after UDLI and to identify factors associated with successful therapy. UDLI was administered for relapsed chronic myelogenous leukemia (CML) (n = 25), acute myelogenous leukemia (AML) (n = 23), acute lymphoblastic leukemia (ALL) (n = 7), and other diseases (n = 3). Eight patients were in complete remission (CR) before UDLI, and 50 were evaluable for response. Forty-two percent (95% confidence interval [CI], 28%-56%) achieved CR, including 11 of 24 (46%; 95% CI, 26%-66%) with CML, 8 of 19 (42%; 95% CI, 20%-64%) with AML, and 2 of 4 (50%; 95% CI, 1%-99%) with ALL. The estimated probability of disease-free survival (DFS) at 1 year after CR was 65% (95% CI, 50%-79%) for CML, 23% (95% CI, 9%-38%) for AML, and 30% (95% CI, 6%-54%) for ALL. Acute graft-versus-host disease (GVHD) complicated UDLI in 37% of patients (grade II-IV, 25%). A total of 13 of 32 evaluable patients (41%) developed chronic GVHD. There was no association between cell dose administered and either response or toxicity. In a multivariable analysis, only a longer interval from BMT to relapse and BMT to UDLI was associated with improved survival and DFS, respectively. UDLI is an acceptable alternative to other treatment options for relapse after unrelated donor BMT. (Blood. 2000;95:1214-1221)     

Donor Leukocyte Infusion for Japanese Patients with Relapsed Leukemia After Allogeneic Bone Marrow Transplantation: Indications and Dose Escalation

Abstract: To clarify the role of dose escalation of donor leukocyte infusion (DLI) in the treatment of relapsed leukemia after allogeneic bone marrow transplant (BMT), data from 100 patients were collected from 46 facilities in Japan and analyzed with respect to indications and infused cell dose. Complete remission (CR) was achieved in 11 of 12 (91%) patients with relapsed chronic myelogenous leukemia (CML) in the chronic phase, 3 of 11 (27%) with CML in the acute phase, 8 of 21 (38%) with acute myelogenous leukemia (AML), 6 of 23 (25%) with acute lymphoblastic leukemia (ALL), and 5 of 11 (45%) with myelodysplastic syndrome (MDS). The probability of remaining in CR at 3 years was 82% in CML patients in the chronic phase, but 0% in those with CML in the acute phase, 7% in those with AML, 0% with ALL, and 33% with MDS. Acute graft‐versus‐host disease (GVHD) (≥2) developed in 31 of 89 (34%) patients with human leukocyte antigen identical related donors and was fatal for 7 (7%). A leukocyte dose of 1 × 10⁷/kg of recipient body weight with CML in the chronic phase, 3 × 10⁷/kg of recipient body weight with MDS, and 1 × 10⁸/kg of recipient body weight with acute leukemia appeared to be optimal as an initial dose of DLI. However, the minimal dose of leukocyte developing fatal GVHD was 7 × 10⁷/kg of recipient body weight. These suggest that a relatively small dose of DLI ranging from 1 × 10⁷/kg to 5 × 10⁷/kg of recipient body weight should be administered initially then the infused escalating dose 2 or 3 months later in patients with CML in the chronic phase and MDS. However, a large number of leukocytes around 1 × 10⁸/kg are needed to induce graft versus leukemia effects in patients with acute leukemia despite a 7% fatality in GVHD.     

Factors affecting the outcome of allogeneic bone marrow transplantation for adult patients with refractory or relapsed acute leukaemia

We evaluated the outcome of allogeneic bone marrow transplantation (BMT) for advanced acute myeloid leukaemia (AML) and acute lymphoblastic leukaemia (ALL) in 383 adult patients in nine Australian adult BMT centres between 1981 and 1997. The median overall survival for the group was 4.8 months, with an estimated 5-year survival of 18%. 28% of patients died of transplant-related toxicities within the first 100 d. Progressive disease was responsible for 48% of deaths. Multi-factor analysis demonstrated that AML (v ALL), disease status (second complete remission [CR2] v others), age (< 40 years) and duration of prior first complete remission (CR1) (> 6 months) were pre-transplant variables significantly associated with improved survival. Acute graft-versus-host disease (GVHD) of any grade reduced the rate of relapse in both AML and ALL, but only grades I-II were associated with improved survival. Both limited and extensive chronic GVHD were associated with increased survival. Only patients with AML in untreated first relapse or CR2, with a duration of CR1 > 6 months, or patients with T ALL, had a 5-year survival > 20%. Transplants for AML in induction failure or pre-B ALL in untreated first relapse or CR2 had an intermediate outcome, with 5-year survival of 10-20%. A 5-year survival of < 10% was observed for patients transplanted for ALL in induction failure or for pre-B ALL or AML in refractory first relapse or beyond CR2. These results suggest that for most adult patients with advanced acute leukaemia an allograft offers only a small chance of cure.     

Prospective Trial of High-Dose Chemotherapy Followed by Infusions of Peripheral Blood Stem Cells and Dose-Escalated Donor Lymphocytes for Relapsed Leukemia after Allogeneic Stem Cell Transplantation

To determine whether induction of graft-versus-host disease (GVHD) improves the outcome of acute relapsed leukemia after stem cell transplantation (SCT), we used high-dose cytarabine (ara-C) followed by infusions of donor-derived buffy coats containing peripheral blood stem cells to treat 12 patients with relapsed leukemia. Donor lymphocyte infusion (DLI) was repeated at least twice over a 5-week interval for patients in whom grade II to IV acute GVHD did not develop after the first DLI. Grade II to IV acute GVHD developed in 4 (33%) of the patients. Chronic GVHD developed in 3 patients, 2 of whom had not experienced acute GVHD. Four (67%) of the 6 patients who developed grade II to IV acute and/or chronic GVHD after DLI responded, but none of the other 6 patients responded. Four (33%) of the patients (2 with acute myelogenous leukemia [AML] and 2 with acute lymphoblastic leukemia [ALL]) achieved complete remission lasting longer than 4 months after the first DLI, but 3 of them had relapses in bone sites. Of these 4 patients, 1 patient with AML and 2 with ALL were alive 8 to 27 months after DLI. These findings indicate that high-dose ara-C combined with megadose DLI may produce durable remission of acute leukemia that has relapsed after SCT when GVHD is induced. The low induction rate of GVHD and extramedullary relapse after remission is achieved with DLI are problems yet to be solved.     

Donor lymphocyte infusion induced molecular remission in relapse of acute myeloid leukaemia after allogeneic bone marrow transplantation.

Donor lymphocyte infusion (DLI) has been used successfully to induce remissions in relapse of acute myeloid leukaemia (AML) after bone marrow transplantation (BMT), but molecular eradication of leukaemia has rarely been documented. A patient with AML-M4Eo relapsed after HLA-identical sibling BMT in first complete remission (CR). Cytogenetic and molecular genetic investigations confirmed inv(16) and CBFbeta/MYH11 fusion characteristic of M4Eo. A second remission was obtained with chemotherapy. Full donor chimerism was demonstrated by fluorescence in situ hybridisation. However, molecular evidence of minimal residual disease still persisted, and donor lymphocyte infusion (DLI) was administered. This resulted in molecular eradication, and the patient remained in clinical and molecular remission 16 months from DLI. Our observations showed that, for AML relapse after BMT, molecular leukaemia eradication could be achieved by DLI so that, in cases where genetic markers are available, molecular monitoring should be performed to assess the efficacy of treatment.     

Donor leukocyte infusions in acute lymphocytic leukemia

Donor leukocyte infusion (DLI) has well-documented activity in CML but the role of DLI in other diseases is less well defined. To evaluate the strategy in acute lymphocytic leukemia (ALL) we evaluated 44 ALL patients from 27 centers who were treated with DLI. Patients with persistent or recurrent disease received DLI from the original marrow donor (30 matched related, four mismatched family, and 10 matched unrelated). Chemotherapy was given before DLI to 28 patients. Of 15 patients who received no pre-DLI chemotherapy, two achieved complete remissions, lasting 1112 and 764+ days. In four patients who received DLI as consolidation of remission induced by chemotherapy or immunosuppression-withdrawal, duration of remission post DLI was 65, 99, 195 and 672+ days. Of 25 patients who received DLI in the nadir after chemotherapy, 13 survived > or =30 days post DLI but did not achieve remission, seven died within less than 30 days post DLI, and five entered remissions that lasted 42, 68, 83, 90, 193 days. Seven patients who did not respond to the initial DLI received a second DLI; none of these patients attained durable remission. Eighteen of 37 evaluable patients developed acute GVHD and five of 20 evaluable patients developed chronic GVHD. Overall actuarial survival is 13% at 3 years. In conclusion, DLI has limited benefit in ALL. New approaches are needed in this group of patients.     

Relapse after allogeneic bone marrow transplantation for acute leukaemia: a survey by the E.B.M.T. of 117 cases

A multi-centre retrospective analysis on 117 patients relapsing after bone marrow transplantation (BMT) for acute leukaemia was carried out by the Leukaemia Working Party of the European Group for Bone Marrow Transplantation (E.B.M.T.). Forty-one patients had acute myeloid leukaemia (AML) and 76 had acute lymphoblastic leukaemia (ALL). Relapse occurred between 3 and 30 months after BMT and where investigated the leukaemia was found to have relapsed in recipient cells. In 10 cases the relapse was associated with new cytogenetic abnormalities. 74 patients received further treatment for leukaemia. Of these 21 out of 50 with ALL and 11 out of 24 with AML achieved a complete remission and had a median survival of 12 months compared with a median survival of 4 months for untreated patients or patients not achieving complete remission (P less than 0.001). Factors predictive for successful remission induction were a long interval between bone marrow transplant and relapse in ALL patients; and isolated extramedullary relapse. Presenting blast count, karyotype and remission status and number at the time of BMT were not predictive. Donor bone marrow was shown to be responsible for haemopoietic recovery occurring in the 21 out of 31 patients tested who achieved remission using donor karyotype or red blood cell antigens as markers. Nine patients received a second bone marrow transplant but only one became a long-term survivor. The results show that chemotherapy can usually prolong survival in selected patients with acute leukaemia relapsing after BMT but further BMT has a poor outlook.     

Allogeneic bone marrow transplantation for acute leukaemia: comparative outcomes for adults and children

Advances in both allogeneic marrow transplantation and conventional therapy for acute leukaemia have complicated the choice between bone marrow transplantation (BMT) and other remission treatment options. Because older patients may be more susceptible to BMT-related complications, this study analysed the effect of age on clinical outcome for 149 patients with acute leukaemia in remission receiving allogeneic BMT. Overall projected relapse-free survival at 3 years post-transplant is equivalent for 48 adults (18 years or older) and 101 children (less than 18) at 45.4% (31.1-59.6; 95% confidence interval) and 39.9% (30.1-49.7; 95% C.I.), respectively. Among 73 patients with acute lymphocytic leukaemia (ALL) 35.3% of adults and 30.1% of children survive relapse-free at 3 years. Cox multiple regression analysis demonstrated that higher diagnostic white count, but not pre-transplant extramedullary leukaemia, remission number, or age, was important as an independent adverse clinical prognostic factor for patients with ALL. Overall outcome was better for 76 patients with acute myeloid leukaemia (AML) with 51.6% of adults and 52.9% of children surviving relapse-free at 3 years post-transplant. Cox multivariate regression analysis identified first remission status and lower white cell count, but not patient age, as independent predictors of improved relapse-free survival for AML patients. Adults had greater transplant morbidity, predominantly related to a higher incidence of acute graft-versus-host disease (GVHD), resulting in longer hospital stay. Survival at 100 d, long-term survival and clinical performance status were similar in both age groups. These data suggest that results of allogeneic BMT for adults with acute leukaemia compare favourably with those found in children and are superior to most reports of conventional chemotherapy. Allogeneic BMT remains a reasonable option for remission acute leukaemia patients up to the age of 45.     

Donor leukocyte infusions for multiple myeloma

Donor leukocyte infusion (DLI) has well-documented activity in CML, but the role of DLI in other diseases is less well defined. To evaluate the strategy in multiple myeloma (MM) we evaluated 25 MM patients from 15 centers who were treated with DLI. Patients with persistent or recurrent disease after allogeneic BMT received DLI from the original marrow donor (23 matched related, one mismatched family, and one matched unrelated). Chemotherapy was given before DLI in three patients. Two of 22 patients responded completely to DLI alone and three patients responded to the combination of DLI and chemotherapy. Nine patients who had not had sufficient disease control after DLI were given additional DLIs; five of these patients had either complete (two) or partial (three) responses. Thirteen of 25 evaluable patients developed acute GVHD and 11 of 21 evaluable patients developed chronic GVHD; all responders developed GVHD. No patients developed post-DLI pancytopenia. Four patients had responses which lasted >1 year after DLI, three patients had responses which lasted <1 year, and three patients had ongoing responses but with follow-up <1 year. In conclusion, DLI has anti-myeloma activity but the strategy is limited by no response or short duration of response in a significant percentage of patients and by significant GVHD in the majority of the responders.     

Clinical impact of graft-versus-host disease against leukemias not in remission at the time of allogeneic hematopoietic stem cell transplantation from related donors. The Japan Society for Hematopoietic Cell Transplantation Working Party

Acute graft-versus-host disease (GVHD) increases post-transplant mortality and morbidity, but exerts a potent graft-versus-leukemia (GVL) effect. To clarify the impact of GVHD on outcome after transplant in aggressive diseases, patients with acute myeloid or lymphoblastic leukemia (AML, n = 366 or ALL, n = 255) in nonremission states, or chronic myelogenous leukemia (CML, n = 180) in accelerated phase (AP) or blastic crisis (BC), who received allogeneic hematopoietic stem cell transplantation (HSCT) from a related donor between 1991 and 2000, were analyzed. Significant improvement in overall and disease-free survival (DFS) was detected with grade I acute GVHD in AML (P = 0.0002 for overall survival and 0.0009 for DFS, respectively) and in CML (P = 0.0256 and 0.0366, respectively), while the trend towards improved survival was observed in ALL. Relapse rate was lower in grade I acute GVHD than in grade II in all three diseases, suggesting that treatment for grade II GVHD may compromise the GVL effect associated with GVHD. Chronic GVHD was found to suppress relapse in CML and ALL, but not in AML, although no improvement in survival was observed in any disease category. Our results suggest that treatment for grade II acute GVHD may need to be attenuated in transplant for refractory leukemias.     

Association of natural killer cell immune recovery with a graft-versus-leukemia effect independent of graft-versus-host disease following allogeneic bone marrow transplantation

 There is good evidence that T lymphocytes play an important role in the graft-versus-leukemia (GVL) effect following allogeneic bone marrow transplantation (BMT) for hematologic malignancies. However, the role of natural killer (NK) cells in GVL is less clear. To further investigate a possible association of NK cells with GVL we studied 15 patients undergoing BMT for chronic myeloid leukemia (CML), correlating T-cell (CD4+ and CD8+) and NK-cell (CD16+56+) recovery with relapse and graft-versus-host disease (GVHD). Patients were studied on three occasions up to 9 months after BMT, for lymphocyte surface phenotype and for spontaneous and IL-2-stimulated (LAK cell) cytotoxic function. Circulating CD8+ and NK but not CD4+ cell numbers were significantly lower in five patients who relapsed compared with those remaining in remission after BMT (mean 0.03 vs 0.32×10⁹/l, p=0.002 for CD8+ cells; mean 0.03 vs 0.11×10⁹/l, p=0.002 for NK cells). There was no correlation of CD4+, CD8+, or NK cell numbers and development of grade-II or more acute GVHD. Spontaneous NK cytotoxic function rose to within the normal range in the first month after BMT. LAK function remained low during the study period. These results link NK cell recovery more closely with a GVL than with a GVH effect. Received: 1 May 1996/Accepted: 19 September 1996