Graft-versus-host disease following allogeneic transplantation from HLA-identical sibling with antithymocyte globulin-based reduced-intensity preparative regimen

Reduced-intensity conditioning (RIC) regimens are increasingly used for allogeneic stem cell transplantation (allo-SCT). RIC has been shown to allow engraftment with minimal early transplantation-related mortality (TRM). However, in the context of RIC, predictive factors for acute and chronic graft-versus-host disease (aGVHD and cGVHD, respectively) and their effect on outcome remain unknown. In this report, we analyzed the outcome of 101 high-risk patients (70 hematologic and 31 nonhematologic malignancies) who received an HLA-identical sibling allo-SCT after RIC, including fludarabine, busulfan, and antithymocyte globulin (ATG). The cumulative incidence of grade II-IV aGVHD was 36% (95% confidence interval [CI], 27%-45%), whereas the cumulative incidence of cGVHD at 2 years was 43% (95% CI, 33%-53%). In multivariate analysis, the incidence of aGVHD was significantly associated with the ATG dose infused during conditioning (P =.0005), whereas peripheral blood as stem cell source was the only predictive factor for the development of cGVHD (P =.0007). The 1-year cumulative incidences of disease progression or relapse in patients with (n = 69) and without (n = 31) GVHD (whatever its form or grade) were 30% (95% CI, 19%-41%) and 55% (95% CI, 37%-72%), respectively (P =.02), suggesting that a potent graft-versus-tumor (GVT) effect can be achieved in high-risk patients following RIC. Moreover, the GVT effect was closely associated with GVHD without an increased risk of TRM (cumulative incidence of TRM, 18% [95% CI, 10%-25%]). Collectively, these results provide a framework for the refinement of RIC approaches designed to enhance the GVT effect with an acceptable risk of GVHD.     

Strategies to reduce transplant-related mortality after allogeneic stem cell transplantation in elderly patients: Comparison of reduced-intensity conditioning and unmanipulated peripheral blood stem cells vs a myeloablative regimen and CD34+ cell selection

OBJECTIVES: The aim of this study was to compare two approaches used to reduce transplant-related mortality (TRM) after allogeneic peripheral blood stem cell transplantation (allo-PBSCT) in elderly patients. PATIENTS AND METHODS: Data from 50 patients, 45 years of age or older, consecutively treated with an HLA-identical sibling allo-PBSCT at the Hospital de Sant Pau were analyzed. We have compared the outcome of patients treated with conventional myeloablative regimens and CD34(+)-selected cells (CD34(+) group; n=23) with those receiving reduced-intensity conditioning regimens, consisting of fludarabine (150 mg/m(2)) plus an alkylating agent, followed by unmanipulated grafts (RIC group; n=27). Patient characteristics were well balanced between the two groups, although patients in the RIC group were slightly older. RESULTS: The incidence of acute graft-vs-host disease (GVHD) was similar in both groups. The 1-year cumulative incidence of extensive chronic GVHD was 38% in the RIC group and 17% in the CD34(+) group (p=0.2). After a median follow-up of 28 months, there were no differences in the relapse rate. Patients in the RIC group had a lower TRM, with a cumulative incidence of 7% vs 30% at 6 months and 15% vs 39% at 1 year (p=0.05). The Kaplan-Meier estimates of PFS at 2 years was 67% in the RIC group and 43% in the CD34(+) group (p=0.09) and the OS was 69% vs 43% (p=0.05), respectively. CONCLUSION: CD34(+) cell selection reduced the risk of extensive cGVHD but was associated with a higher TRM. Although the number of patients is limited, our study suggests that this approach should be restricted to relatively young patients, as better outcomes can be achieved in elderly patients using RIC strategies.     

Graft-versus-myeloma effect following antithymocyte globulin-based reduced intensity conditioning allogeneic stem cell transplantation

In all, 41 multiple myeloma (MM) patients received an antithymocyte globulin (ATG), fludarabine, and busulfan-based reduced intensity conditioning (RIC) for allogeneic stem cell transplantation (allo-SCT) from HLA-identical siblings. In total, 29 patients (70%) were in partial remission, one patient in complete remission, and 11 (27%) with progressive disease at the time of allo-SCT. Median time between diagnosis and allo-SCT was 24 months. The cumulative incidences of grade II-IV and grade III-IV acute graft-versus-host disease (GVHD) were 36% (95% CI, 21-51%) and 7% (95% CI, 2-20%), respectively. Overall, 10 patients developed limited chronic GVHD, whereas seven developed an extensive form (cumulative incidence, 41% (95% CI, 26-56%) at 2 years). With a median follow-up of 389 days, the overall cumulative incidence of transplant-related mortality (TRM) was 17% (95% CI, 6-28%). In all, 11 patients (27%) are in continuous complete remission, and the Kaplan-Meier estimates of overall survival (OS) and progression-free survival (PFS) at 2 years were 62% (95% CI, 47-76%) and 41% (95% CI, 23-62%), respectively. PFS and OS were significantly higher in patients with chronic GVHD as compared to patients without chronic GVHD (P=0.006 for PFS and P=0.01 for OS). Collectively, these data demonstrate that RIC allo-SCT can mediate a potentially curative graft-versus-myeloma effect with an acceptable incidence of toxicity and TRM.     

A randomized multicenter comparison of CD34(+)-selected progenitor cells from blood vs from bone marrow in recipients of HLA-identical allogeneic transplants for hematological malignancies

OBJECTIVE: Peripheral blood progenitor cells (PBPC) have been established as an alternative source of hematopoietic stem cells for allogeneic transplantation, but an increased incidence of both acute and chronic graft-vs-host disease (GVHD) has become apparent. We performed a prospective randomized trial comparing bone marrow transplantation (BMT) vs PBPC transplantation (PBPCT) using CD34(+) selection for T-cell depletion (TCD) in both study arms. PATIENTS AND METHODS: Between January 1996 and October 2000, 120 patients with a diagnosis of acute leukemia, myelodysplasia, multiple myeloma, or lymphoma were randomized to receive either filgrastim-mobilized PBPC or BM from HLA-identical sibling donors after standard high-dose chemoradiotherapy. Patient characteristics did not differ between study arms. RESULTS: Recipients of PBPC received more CD3(+) T cells (median: 3.0 vs 2.0 x 10(5)/kg, p<0.0001) and more CD34(+) cells (median: 3.6 vs 0.9 x 10(6)/kg, p<0.0001). Neutrophil and platelet recoveries occurred significantly faster after PBPCT. The cumulative incidence of acute GVHD grades II-IV was 37% after BMT vs 52% after PBPCT and was most significantly (p=0.007) affected by the number of CD3(+) T cells in the graft. Acute GVHD appeared strongly associated with increased treatment-related mortality (TRM) in a time-dependent analysis. Higher numbers of CD34(+) cells were associated with less TRM. With a median follow-up of 37 months (range: 12-75), overall survival at 4 years from transplantation was 60% after BMT and 34% for recipients of PBPCT (p=0.04), which difference was largely due to increased GVHD and TRM in PBPC recipients receiving T-cell dosages greater than 2 x 10(5)/kg. CONCLUSION: Outcome following T cell-depleted PBPCT critically depends on the number of CD3(+) T cells, whereby high T-cell numbers may blunt a favorable effect of higher CD34(+) cell numbers.     

Early matched sibling hematopoietic cell transplantation for adult AML in first remission using an age-adapted strategy: long-term results of a prospective GOELAMS study

The LAM2001 phase 3 trial, involving 832 patients with acute myeloid leukemia (AML; median: 46 years) proposed HLA-identical sibling allograft HSCT for all patients with an identified donor. The trial compared reduced-intensity conditioning (RIC) for patients older than 50 years of age (N = 47) and myeloablative conditioning for younger patients (N = 117). BM HSCT was performed in the younger patients, while the older ones received a consolidation course, followed by peripheral blood allo-HSCT using RIC. The incidence of grade II-IV acute GVHD, was 51.9% (95% confidence interval [CI]: 42.1-61.8) and 11.3% (1.6-21.2) after myeloablative or RIC, respectively (P < .0001) and that of chronic GVHD 45.8% (95% CI: 34.8-56.7) and 41.7% (24.7-58.6; NS). Cumulative incidence of nonrelapse mortality at 108 months was 15.8% (95% CI: 9.8-23.2) for myeloablative, and 6.5% (0.2-16.2) for RIC (NS). CI of relapse at 108 months was 21.7% (95% CI: 13.9-28.6) and 28.6% (16.5-43.4; NS). Overall survival at 108 months was 63.4% (95% CI: 54.6-72.2) and 65.8% (52.2-72.2), respectively, after myeloablative or RIC (NS). RIC peripheral blood stem cell allo-HSCT is prospectively feasible for patients between the ages of 51 and 60 years without excess of relapse or nonrelapse mortality, and compares favorably with myeloablative marrow allo-HSCT proposed to younger patients.     

Unrelated donor marrow transplantation for myelodysplastic syndromes: outcome analysis in 510 transplants facilitated by the National Marrow Donor Program

Between April 1988 and July 1998, 510 patients with myelodysplastic syndromes (MDS) underwent unrelated donor bone marrow transplantation (BMT) facilitated by the National Marrow Donor Program. Median age was 38 years (range, <1-62 years). Several conditioning regimens and graft-versus-host disease (GVHD) prophylaxis methods were used, and T-cell depletion was used in 121 patients. Donors were serologically matched for HLA-A, -B, and -DRB1 antigens for 74% of patients. Of 437 patients evaluable for engraftment, 24 (5% cumulative incidence, with 95% confidence interval [CI] of 3%-7%) failed to engraft, and an additional 33 (8% cumulative incidence; 95% CI, 6%-10%) had late graft failure. Grades II to IV GVHD developed in 47% of patients (95% CI, 43%-49%), and limited and extensive chronic GVHD developed at 2 years in 27% (95% CI, 24%-30%). The incidence of relapse at 2 years was 14% (95% CI, 11%-17%). Greater relapse was independently associated with advanced MDS subtype and no acute GVHD. The estimated probability of disease-free survival (DFS) at 2 years was 29% (95% CI, 25%-33%). Improved DFS was independently associated with less advanced MDS subtype, higher cell dose, recipient cytomegalovirus (CMV) seronegativity, shorter interval from diagnosis to transplantation, and transplantation in recent years. Common causes of death were treatment-related complications accounting for 82% of fatalities. The 2-year cumulative incidence of treatment-related mortality (TRM) was 54% (95% CI, 53%-61%). Sixty-nine percent of TRM occurred within the first 100 days, and 93% occurred within the first year of transplantation. Higher TRM was independently associated with older recipient and donor age, HLA mismatch, and recipient CMV seropositivity. This study demonstrates that unrelated donor BMT cures a significant proportion of patients with MDS. TRM is the major problem limiting the success of unrelated donor BMT in MDS. The observations made in this study should facilitate the design of prospective trials aimed at improving the results of unrelated donor stem cell transplantation for MDS.     

Predictors of prolonged survival after allogeneic hematopoietic stem cell transplantation for multiple myeloma

A total of 149 patients with multiple myeloma (MM) who received allogeneic hematopoietic stem cell transplantation (allo-HCT) with myeloablative (MAC; n = 38) or reduced-intensity conditioning (RIC; n = 110) regimens at MD Anderson Cancer Center were evaluated. Of the total, 120 (81%) patients had relapsed or had refractory disease. Median age of MM patients was 50 (28-70) years with a followup time of 28.5 (3-164) months. The 100-day and 5-year treatment related mortality (TRM) rates were 17% and 47%, respectively. TRM was significantly lower with RIC regimens (13%) vs. 29% for MAC at 100 days (P = 0.012). The cumulative incidence of Grade II-IV acute graft-versus-host disease (GVHD) was 35% and chronic GVHD was 46%. PFS and OS at 5 years were 15% and 21%, respectively. In multivariate analysis, allo-HCT for primary remission consolidation was associated with longer PFS (HR 0.35; 95% CI, 0.18-0.67) and OS (HR 0.29; 95% CI 0.15-0.55), while absence of high-risk cytogenetics was associated with longer PFS only (HR 0.59; 95% CI 0.37-0.95). We observe that TRM has decreased with the use of RIC regimens, and long-term disease control can be expected in a subset of MM patients undergoing allo-HCT. Further studies should be conducted in carefully designed clinical trials in this patient population.     

Clinical effect of reduced-intensity conditioning regimen containing antithymocyte globulin for hematopoietic cell transplantation from unrelated-donors

The impact of reduced-intensity conditioning (RIC) on the outcomes of hematopoietic cell transplantation (HCT) from unrelated -donors (UD) remains to be determined. We therefore assessed 128 patients, aged 16 to 66 years, with acute leukemia (n = 105) or myelodysplastic syndrome (n = 23) in a UD-HCT trial using RIC with busulfan, fludarabine, and antithymocyte globulin. Patients were transplanted with unmanipulated bone marrow (BM, n = 41) or mobilized peripheral blood mononuclear cells (M-PB, n = 87) and received cyclosporine and methotrexate for graft-versus-host disease (GVHD) prophylaxis. After a median follow-up of 26.7 months (range, 5.9-70.7 months) in surviving patients, 19 patients had died without progression/recurrence of underlying disease, giving a cumulative incidence of transplantation-related mortality (TRM) of 17% (95% confidence interval, 11%-27%; 1-year TRM, 14%). Graft failure (n = 7) and infections (n = 5) were the most common causes of TRM. Only three patients died due to GVHD (acute, one; chronic, two). Graft failure, which occurred in eight patients, showed a significant correlation with graft source (BM, 6/41 vs. M-PB, 2/87; P = 0.009). Donor-patient HLA-disparity did not correlate with GVHD, 1-year TRM, and graft failure. RIC containing antithymocyte globulin led to decreased GVHD-associated, as well as overall, TRM after UD-HCT.     

Nonmyeloablative allogeneic stem cell transplantation (NST) after truly nonmyeloablative and reduced intensity conditioning regimens

Nonmyeloablative allogeneic stem cell transplantation (NST) has been explored to overcome transplant-related mortality (TRM). From the review of 39 published reports, 50% of the 1484 treated patients had NSTs with truly nonmyeloablative conditioning (NMC) and 417 patients (29%) received an unrelated donor transplant (UDT). Median age was 49 years (range 17-59). A median dose of 4.74 x 10(6) CD34+ per kg (range 1.7-7.5) was administered. Hematological recovery was rapid with all the regimens used. Sustained engraftment was obtained in 1267/1355 assessable patients (94%, range 67-100%). Complete donor chimerism was observed in 707/948 assessable patients (75%, range 22-100%). Both were higher after reduced intensity conditioning (RIC) than after NMC regimens. Reject was more frequent after UDT and NMC regimens. Grades II-IV and III-IV acute graft versus host disease (GVHD) occurred in 580/1400 (41%; range 7-72%) and 188/1093 (17%; range 0-29%) assessable patients, respectively; grades II-IV and III-IV acute GVHD were more frequent after UDT and RIC regimens, respectively. Chronic GVHD occurred in 407/1046 assessable patients (39%; range 0-79%) and extensive chronic GVHD in 166/835 patients (20%; range 0-69%); they were more frequent after RIC regimens and less frequent after UDT. Transplant-related mortality (TRM) rate of 20.6%, without differences between RIC and NMC regimens, was observed; TRM was higher with UDTs. The most frequent causes of TRM were acute or chronic GVHD after RIC regimens and infections after NMC regimens and UDTs. Indolent lymphoid malignancies and some solid tumors appear sensitive to the graft versus malignancy (GVM) effect. NSTs could guarantee relatively low TRM and toxicity in patients not eligible for conventional allogeneic transplantation and could represent a platform for successive specific immunotherapy.     

Possibility of long-term remission in patients with advanced hematologic malignancies after reduced intensity conditioning regimen (RIC) and allogeneic stem cell transplantation

High-dose chemotherapy and radiation used as a preparative regimen for allogeneic stem cell transplantation (SCT) produces a considerable morbidity and mortality. An alternative strategy, developed to reduce transplant-related toxicity and to induce graft versus malignancy effect in the presence of full hematopoietic engraftment, includes the application of RIC that provide sufficient immunosuppression. We studied the efficacy and toxicity of RIC followed by allogeneic SCT in elderly patients or with relative contraindications to conventional SCT. In all, 22 patients with hematologic malignancies and HLA-identical sibling donors were included in this study. All patients were either refractory to therapy or beyond first complete remission (CR). The majority of patients received fludarabine 120 mg/m(2)+thiotepa 10 mg/kg as conditioning regimen and cyclosporine as graft versus host disease (GVHD) prophylaxis. Organ toxicity was acceptable and all evaluable patients achieved engraftment. Three patients (15%) showed grade >II aGVHD; extensive chronic GVHD occurred in three out of 15 evaluable patients (20%). With median follow-up of 63.5 months, survival was 31%, disease-free survival (DFS) was 23%. All the durable responses occurred in patients who developed GVHD. Transplant related mortality (TRM) at 100 days was 27.3%, 67% of that caused by infections, while 6-year cumulative incidence of TRM was 38%. Our data show that RIC: (1). allows the engraftment of HLA-matched hematopoietic stem cells (2). provide durable responses in patients not eligible for conventional SCT exploiting the graft-versus-malignancy effect and (3). is loaded by an high rate of fatal infections.     

Reduced-intensity preparative regimen and allogeneic stem cell transplantation for advanced solid tumors

In this prospective multicenter program, we investigated allogeneic stem cell transplantation (ASCT) from HLA-identical siblings following reduced-intensity conditioning (RIC) regimen for patients with refractory metastatic solid tumors (STs). Fifty-seven patients, of whom 39 had a progressive disease (PD) at time of ASCT, received an RIC ASCT combining fludarabine, antithymocyte globulin (ATG), and busulfan. Patients were analyzed in terms of engraftment, transplant-related mortality (TRM), disease response, and outcome. In this setting, RIC was associated with rapid engraftment and low overall TRM (9% [95% confidence interval (CI), 1%-16%]). The cumulative incidence of objective responses (ORs) reached 14% (95% CI, 6%-30%) with this being significantly higher in patients without PD (44% [95% CI, 21%-67%] versus 0; P <.0001) at time of ASCT. Achievement of OR translated into a significantly better overall survival (OS). In multivariate analysis, OS was significantly influenced by disease status at time of ASCT (odds ratio, 4.88; P <.001) and chronic graft-versus-host disease (GVHD) occurrence (odds ratio, 2.86; P <.01). Overall, these results showed that OR can occur after RIC ASCT for resistant ST with a relatively low TRM and potential benefit especially in patients with slowly progressive disease. Further studies are warranted in patients with less advanced ST.     

Risk factors for acute graft-versus-host disease after allogeneic blood stem cell transplantation.

We evaluated demographic characteristics and graft composition as risk factors for acute graft-versus-host disease (GVHD) in 160 adult recipients of HLA-identical allogeneic blood stem cell transplants. The patients received a median nucleated cell dose of 7.9 x 10(8)/kg and median C34(+) cell dose of 5.6 x 10(6)/kg. GVHD prophylaxis consisted of cyclosporine (CSA) and steroids, tacrolimus (FK506) and steroids, or FK506 and methotrexate. Grades 2 to 4 GVHD occurred in 31% (95% CI, 23% to 39%), and grades 3 to 4 GVHD in 14% (95% CI, 8% to 20%). In univariate analyses, GVHD prophylaxis with CSA and high CD34(+) cell doses were significant risk factors for grades 2 to 4 GVHD, but diagnosis, age, use of total body irradiation, donor sex, female donor for male recipient, donor parity, donor alloimmunization, viral serology, nucleated cell dose, CD3(+) cell dose, and CD56(+) cell dose did not alter the incidence of GVHD significantly. With a CD34(+) cell dose less than 8 x 10(6) CD34(+) cells/kg, the risk of grades 2 to 4 GVHD was significantly higher for those who received CSA (39%, 95% CI, 21% to 47%) in comparison with those on FK506 (18%, 95% CI, 10% to 26%) (P =.03), but GVHD prophylaxis regimen had less impact with a higher CD34(+) cell dose (overall grades 2 to 4 GVHD rate 52%, 95% CI, 37% to 67%). GVHD prophylaxis and CD34(+) cell dose are independent risk factors for acute GVHD after allogeneic blood stem cell transplantation.     

Conventional versus reduced-intensity conditioning regimen for allogeneic stem cell transplantation in patients with hematological malignancies

BACKGROUND: Allogeneic hematopoietic stem cell transplantation (HSCT) from human leukocyte antigen (HLA)-compatible sibling donors is a potential curative treatment for hematological and non-hematological malignancies. Nevertheless, high mortality rates may be associated with this therapy, especially in older patients, those with other comorbidities or who receive a second HSCT. PATIENTS AND METHODS: We analyzed the factors associated with transplant-related mortality (TRM) and overall survival in 157 consecutive adult patients (104 males and 53 females) who received a HSCT [29 bone marrow (BM) transplantation and 128 peripheral blood (PB) transplantation] from a HLA-identical sibling between January 1995 and March 2002 in our institution. One hundred patients received a standard conditioning prior to HSCT (STAND) and 57 patients received a reduced-intensity conditioning (RIC) HSCT. Fifty-eight patients were in an early phase at transplant and 99 in a non-early phase. Median age was 46 yr (16-66), and 90 patients (57%) were >45 yr of age. RESULTS: Patients in the RIC group were older than those in the STAND group, and had a higher proportion of non-early disease phases including a prior autologous HSCT in 39%. Median follow-up for survivors was 28 and 15 months in the STAND and RIC groups (P < 0,001), respectively. Cumulative incidence of TRM at 2 yr was 30% [95% confidence interval (CI) 22-41%] for the STAND group and 22% (95% CI 13-37%) for the RIC group [non-significant (NS)]. Factors associated with a higher TRM in multivariate analysis were: STAND vs. RIC conditioning regimen [relative risk (RR) 5.4; 95% CI 2.3-12.8; P < 0.001]; age > or =45 yr vs. <45 yr (RR 5; 95% CI 2.4-10.8, P < 0.001); second vs. first HSCT (RR 2.8, 95% CI 1.3-6.3, P = 0.01) and non-T-cell-depleted vs. T-cell-depleted graft (RR 2.7, 95% CI 1.3-5.8, P = 0.009). Overall survival (OS) at 2 yr was 52.5 +/- 10.4% for STAND group and 59 +/- 16.8% in RIC group. Factors associated with poorer OS in multivariate analysis were: STAND vs. RIC conditioning regimen (RR 3.4, 95% CI 1.7-6.9, P = 0.001); age > or =45 vs <45 yr (RR 2.5, 95% CI 1.4-4.5, P = 0.002) and diagnosis [other than chronic myeloid leukemia (CML) vs. CML] (RR 2.6, 95% CI 1.2-5.7 P = 0.02). CONCLUSIONS: Our results indicate that the introduction of RIC allogeneic HSCT for patients at high risk for TRM (advanced age, prior HSCT and non-T-cell depletion) leads to a reduction in the TRM and improvement in the OS.     

Absence of clinical GVHD and the in vivo induction of regulatory T cells after transplantation of facilitating cells

Graft-versus-host disease (GVHD) and failure of engraftment limit clinical bone marrow transplantation (BMT) to patients with closely matched donors. Engraftment failure of purified allogeneic hematopoietic stem cells (HSCs) has been decreased in various BMT models by including donor BM-derived CD8(+)/alphabetagammadeltaTCR(-) facilitating cells (FCs) or CD8(+)/alphabetaTCR(+) T cells in the BM inoculum. To aggressively investigate the GVHD potential of these donor CD8(+) populations, a purified cell model of lethal GVHD was established in a murine semiallogeneic parent --> F(1) combination. Lethally irradiated recipients were reconstituted with purified donor HSCs alone or in combination with splenic T cells (T(SP)), BM-derived T cells (T(BM)), or the FC population. In marked contrast to the lethal GVHD present in recipients of HSCs plus T(SP) or CD8(+) T(BM), recipients of donor HSC+FC inocula did not exhibit significant clinical or histologic evidence of GVHD. Instead, HSC+FC recipients were characterized by increased splenocyte expression of transforming growth factor-beta (TGF-beta) and the induction of the regulatory T-cell genes CTLA4, GITR, and FoxP3. These findings suggest that the FCs, which express a unique FCp33-TCRbeta heterodimer in place of alphabetaTCR, permits HSC alloengraftment and prevents GVHD through the novel approach of regulatory T-cell induction in vivo.     

Differential effects of donor T-cell cytokines on outcome with continuous bortezomib administration after allogeneic bone marrow transplantation

Dissociating graft-versus-tumor (GVT) effect from acute graft-versus-host disease (GVHD) still remains a great challenge in allogeneic bone marrow transplantation (allo-BMT). Bortezomib, a proteasome inhibitor, has shown impressive efficacy as a single agent in patients with hematologic malignancies but can result in toxicity when administered late after allogeneic transplantation in murine models of GVHD. In the current study, the effects of T-cell subsets and their associated cytokines on the efficacy of bortezomib in murine allogeneic BMT were investigated. Increased levels of serum tumor necrosis factor-alpha (TNFalpha) and interferon-gamma (IFNgamma) were observed after allo-BMT and continuous bortezomib administration. Bortezomib-induced GVHD-dependent mortality was preventable by depletion of CD4(+) but not CD8(+) T cells from the donor graft. The improved survival correlated with markedly reduced serum TNFalpha but not IFNgamma levels. Transfer of Tnf(-/-) T cells also protected recipients from bortezomib-induced GVHD-dependent toxicity. Importantly, prolonged administration of bortezomib after transplantation of purified CD8(+) T cells resulted in enhanced GVT response, which was dependent on donor CD8(+) T cell-derived IFNgamma. These results indicate that decreased toxicity and increased efficacy of bortezomib in murine allo-BMT can be achieved by removal of CD4(+) T cells from the graft or by inhibiting TNFalpha.     

Transplant dose of CD34+ and CD3+ cells predicts outcome in patients with haematological malignancies undergoing T cell-depleted peripheral blood stem cell transplants with delayed donor lymphocyte add-back

We sought to optimize and standardize stem cell and lymphocyte doses of T cell-depleted peripheral blood stem cell transplants (T-PBSCT), using delayed add-back of donor T cells (DLI) to prevent relapse and enhance donor immune recovery. Fifty-one patients with haematological malignancies received a T-PBSCT from an HLA-identical sibling, followed by DLI of 1 x 10(7) and 5 x 10(7) CD3(+) cells/kg on d +45 and +100 respectively. Twenty-four patients were designated as standard risk and twenty-seven patients with more advanced leukaemia were designated as high risk. Median recipient age was 38 years (range 10-56). Median (range) of CD34(+) and CD3(+) cell transplant doses were 4.6 (2.3-10.9) x 10(6)/kg and 0.83 (0.38-2) x 10(5)/kg respectively. The cumulative probability of acute GVHD was 39%. No patient died from GVHD or its consequences. The probability of developing chronic GVHD was 54% (18% extensive). The probability of relapse was 12% for the standard-risk patients and 66% for high-risk patients. In multivariate analysis, the risk factors for lower disease-free survival and overall survival were high-risk disease, CD34(+) dose < 4.6 x 10(6)/kg and CD3(+) dose < 0.83 x 10(5)/kg. Predictive factors for chronic GVHD were a T-cell dose at transplant > 0.83 x 10(5) CD3(+) cells/kg. These results further define the impact of CD34 and CD3 cell dose on transplant outcome and show that careful dosing of stem cells and lymphocytes may permit the control and optimization of transplant outcome.     

Risk factors for acute GVHD and survival after hematopoietic cell transplantation

Risk factors for acute GVHD (AGVHD), overall survival, and transplant-related mortality were evaluated in adults receiving allogeneic hematopoietic cell transplants (1999-2005) from HLA-identical sibling donors (SDs; n = 3191) or unrelated donors (URDs; n = 2370) and reported to the Center for International Blood and Marrow Transplant Research, Minneapolis, MN. To understand the impact of transplant regimen on AGVHD risk, 6 treatment categories were evaluated: (1) myeloablative conditioning (MA) with total body irradiation (TBI) + PBSCs, (2) MA + TBI + BM, (3) MA + nonTBI + PBSCs, (4) MA + nonTBI + BM, (5) reduced intensity conditioning (RIC) + PBSCs, and (6) RIC + BM. The cumulative incidences of grades B-D AGVHD were 39% (95% confidence interval [CI], 37%-41%) in the SD cohort and 59% (95% CI, 57%-61%) in the URD cohort. Patients receiving SD transplants with MA + nonTBI + BM and RIC + PBSCs had significantly lower risks of grades B-D AGVHD than patients in other treatment categories. Those receiving URD transplants with MA + TBI + BM, MA + nonTBI + BM, RIC + BM, or RIC + PBSCs had lower risks of grades B-D AGVHD than those in other treatment categories. The 5-year probabilities of survival were 46% (95% CI, 44%-49%) with SD transplants and 33% (95% CI, 31%-35%) with URD transplants. Conditioning intensity, TBI and graft source have a combined effect on risk of AGVHD that must be considered in deciding on a treatment strategy for individual patients.     

Donor CD4+ T-cell production of tumor necrosis factor alpha significantly contributes to the early proinflammatory events of graft-versus-host disease

OBJECTIVE: Tumor necrosis factor alpha (TNFalpha) is an old foe in allogeneic bone marrow transplantation (allo-BMT) promoting acute graft-versus-host disease (aGVHD). We investigated to what extent donor T cells contribute to TNFalpha production. METHODS: Lethally irradiated B6D2F1 mice were transplanted with bone marrow (BM) and T cells from syngeneic B6D2F1 or allogeneic B6 donors and assessed for cytokine production, aGVHD, and survival. RESULTS: Analysis of serum TNFalpha kinetics in recipients of allogeneic B6 wild-type BM and wild-type T cells revealed that TNFalpha levels peaked around day 7 after allo-BMT, whereas TNFalpha was undetectable in syngeneic controls. TNFalpha was produced by both host and donor cells. Further exploration showed that specifically donor CD4(+) but not CD8(+) T cells were the primary donor cell source of TNFalpha at this early time point; numbers of TNFalpha expressing splenic CD4(+) T cells were higher than CD8(+) T cells 7 days after allo-BMT, and maximal serum TNFalpha levels were detected following allo-BMT with only CD4(+) T cells compared to levels found in allogeneic recipients of only wild-type CD8(+) or to only CD4(+) TNFalpha(-/-) T cells. Concurrent with increased TNFalpha levels, early clinical aGVHD and mortality were more severe following allo-BMT with either wild-type CD4(+) and CD8(+) or CD4(+) T cells only. CONCLUSION: Our data demonstrate that in addition to residual host cells donor CD4(+) T cells significantly contribute to the proinflammatory cytokine milieu engendered early after allo-BMT through the production of TNFalpha. These findings support strategies focusing on TNFalpha neutralization as primary treatment for aGVHD.     

Haploidentical allogeneic hematopoietic cell transplantation in adults using CD3/CD19 depletion and reduced intensity conditioning: an update

Haploidentical hematopoietic cell transplantation (HHCT) after high dose conditioning with CD34-selected stem cells has been complicated by high regimen related toxicities, slow engraftment and delayed immune reconstitution leading to increased treatment related mortality (TRM). A new regimen using reduced intensity conditioning (RIC) and graft CD3/CD19 depletion with anti-CD3 and anti-CD19 coated microbeads on a CliniMACS device may allow HHCT with lower toxicity and faster engraftment. CD3/CD19 depleted grafts not only contain CD34+ stem cells but also CD34 negative progenitors, natural killer, graft facilitating and dendritic cells. RIC was performed with fludarabine (150-200 mg/m(2)), thiotepa (10 mg/kg), melphalan (120 mg/m(2)) and OKT-3 (5 mg/day, day -5 to +14) and no posttransplant immunosuppression. Twenty nine patients (median age=42 (range, 21-59) years) have been transplanted with this regimen. Diagnosis were AML (n=16), ALL (n=7), NHL (n=3), MM (n=2) and CML (n=1). Patients were "high risk" with refractory disease or relapse after preceding HCT. The CD3/CD19 depleted haploidentical grafts contained a median of 7.6x10(6) (range, 3.4-17x10(6)) CD34+ cells/kg, 4.4x10(4) (range, 0.006-44x10(4)) CD3+ T cells/kg and 7.2x10(7) (range, 0.02-37.3x10(7)) CD56+ cells/kg. Donor-recipient KIR-ligand-mismatch was found in 19 of 29 patients. The regimen was well tolerated with maximum acute toxicity being grade 2-3 mucositis. Because of severe neurotoxicity in 4 patients treated with 200 mg/m(2) fludarabine, the dose was reduced to 150 mg/m(2). Engraftment was rapid with a median time to >500 granulocytes/microL of 12 (range, 10-21) days, >20,000 platelets/microL of 11 (range, 7-38) days and full donor chimerism after 2-4 weeks in all patients. Incidence of grade II-IV degrees GVHD was 48% with grade II degrees =10, III degrees =2 and IV degrees =2. One patient, who received the highest T-cell dose, developed lethal grade IV GVHD. TRM in the first 100 days was 6/29 (20%) with deaths due to idiopathic pneumonia syndrome (n=1), mucormycosis (n=1), pneumonia (n=3) or GVHD (n=1). Overall survival is 9/29 patients (31%) with deaths due to infections (n=7), GVHD (n=1) and relapse (n=12) with a median follow-up of 241 days (range, 112-1271). In conclusion, this regimen is promising in high risk patients lacking a suitable donor, and a prospective phase I/II study is ongoing.     

Stem cell transplantation with reduced-intensity conditioning for hemophagocytic lymphohistiocytosis

Allogeneic stem cell transplantation (SCT) is curative for hemophagocytic lymphohistiocytosis (HLH). However, patients frequently have significant morbidity before transplantation and there is high transplant-related mortality (TRM). Because first-degree HLH is caused by immune dysregulation, a reduced-intensity conditioned (RIC) regimen might be sufficient for cure while decreasing the TRM. Twelve patients with HLH underwent RIC SCT from a matched family/unrelated or haploidentical donor. Eleven were conditioned with fludarabine/melphalan with additional busulphan for haploidentical grafts. One received fludarabine and 2-Gy total body irradiation (TBI). All patients showed engraftment at a median of 14 days. Nine of 12 (75%) are alive and in complete remission (CR) a median of 30 months (range, 9-73 months) after SCT. Two patients died from pneumonitis and one from hepatic rupture. Four patients developed acute graft-versus-host disease (GVHD) and 3 have chronic GVHD. Three of 9 survivors have mixed chimerism but remain free of disease. In summary, RIC compares favorably to conventional SCT with long-term disease control in surviving patients despite a significant incidence of mixed chimerism.