Metabolic syndrome and cardiovascular disease following hematopoietic cell transplantation: screening and preventive practice recommendations from CIBMTR and EBMT

Metabolic syndrome (MetS) is a constellation of cardiovascular risk factors that increases the risk of cardiovascular disease, diabetes mellitus and all cause mortality. Long-term survivors of hematopoietic cell transplantation (HCT) have a substantial risk of developing MetS and cardiovascular disease, with the estimated prevalence of MetS being 31-49% among HCT recipients. Although MetS has not yet been proven to impact cardiovascular risk after HCT, an understanding of the incidence and risk factors for MetS in HCT recipients can provide the foundation to evaluate screening guidelines and develop interventions that may mitigate cardiovascular-related mortality. A working group was established through the Center for International Blood and Marrow Transplant Research and the European Group for Blood and Marrow Transplantation with the goal of reviewing literature and recommend practices appropriate to HCT recipients. Here we deliver consensus recommendations to help clinicians provide screening and preventive care for MetS and cardiovascular disease among HCT recipients. All HCT survivors should be advised of the risks of MetS and encouraged to undergo recommended screening based on their predisposition and ongoing risk factors.

Alternative donors extend transplantation for patients with lymphoma who lack an HLA matched donor

Alternative donor transplantation is increasingly used for high risk lymphoma patients. We analyzed 1593 transplant recipients (2000 to 2010) and compared transplant outcomes in recipients of 8/8 allele human leukocyte antigen (HLA)-A, -B, -C, and DRB1 matched unrelated donors (MUD; n=1176), 7/8 allele HLA-matched unrelated donors (MMUD; n=275) and umbilical cord blood donors (1 or 2 units UCB; n=142). Adjusted 3-year non-relapse mortality of MMUD (44%) was higher as compared to MUD (35%; p=0.004), but similar to UCB recipients (37%; p=0.19), although UCB had lower rates of neutrophil and platelet recovery compared to unrelated donor groups. With a median follow-up of 55 months, 3-year adjusted cumulative incidence of relapse was lower after MMUD compared with MUD (25% vs 33%, p=0.003) but similar between UCB and MUD (30% vs 33%; p=0.48). In multivariate analysis UCB recipients had lower risks of acute and chronic graft versus host disease compared with adult donor groups (UCB vs MUD: HR=0.68, p=0.05; HR=0.35; p<0.001). Adjusted 3-year overall survival was comparable (43% MUD, 37% MMUD and 41% UCB). Data highlight that patients with lymphoma have acceptable survival after alternative donor transplantation. MMUD and UCB can expand the curative potential of allotransplant to patients who lack suitable HLA-matched sibling or MUD.

Physician perceptions and practice patterns regarding fertility preservation in hematopoietic cell transplant recipients

Physician practice variation may be a barrier to informing hematopoietic cell transplant (HCT) recipients about fertility preservation (FP) options. We surveyed HCT physicians in the United States to evaluate FP knowledge, practices, perceptions and barriers. Of the 1035 physicians invited, 185 completed a 29-item web-survey. Most respondents demonstrated knowledge of FP issues and discussed and felt comfortable discussing FP. However, only 55% referred patients to an infertility specialist. Most did not provide educational materials to patients and only 35% felt that available materials were relevant for HCT. Notable barriers to discussing FP included perception that patients were too ill to delay transplant (63%), patients were already infertile from prior therapy (92%) and time constraints (41%). Pediatric HCT physicians and physicians with access to an infertility specialist were more likely to discuss FP and to discuss FP even when prognosis was poor. On analyses that considered physician demographics, knowledge and perceptions as predictors of referral for FP, access to an infertility specialist and belief that patients were interested in FP were observed to be significant. We highlight variation in HCT physician perceptions and practices regarding FP. Physicians are generally interested in discussing fertility issues with their patients but lack educational materials.

Recommended screening and preventive practices for long-term survivors after hematopoietic cell transplantation

Advances in hematopoietic cell transplantation (HCT) technology and supportive care techniques have led to improvements in long-term survival after HCT. Emerging indications for transplantation, introduction of newer graft sources (eg, umbilical cord blood) and transplantation of older patients using less intense conditioning regimens have also contributed to an increase in the number of HCT survivors. These survivors are at risk for developing late complications secondary to pre-, peri-, and posttransplant exposures and risk factors. Guidelines for screening and preventive practices for HCT survivors were published in 2006. An international group of transplantation experts was convened in 2011 to review contemporary literature and update the recommendations while considering the changing practice of transplantation and international applicability of these guidelines. This review provides the updated recommendations for screening and preventive practices for pediatric and adult survivors of autologous and allogeneic HCT.

Screening, prevention and management of osteoporosis and bone loss in adult and pediatric hematopoietic cell transplant recipients

Long-term survivors of hematopoietic cell transplantation (HCT) are at risk for loss of bone mineral density (BMD) and subsequent osteoporosis. There is a lack of clear guidelines for the screening, prevention and treatment of bone loss after HCT. We reviewed the prevailing literature and provide guidelines developed by our center for the screening and management of this complication. Bone loss occurs predominantly within the first 6-12 months after autologous and allogeneic HCT. Recovery first occurs in the lumbar spine and is followed by a slower recovery of BMD in the femoral neck. BMD may not return to baseline levels in patients with continuing exposure to corticosteroids and calcineurin inhibitors. All HCT recipients should be advised general interventions to reduce fracture risk including adequate intake of calcium and vitamin D. We recommend screening all adult allogeneic and autologous HCT recipients with dual-energy X-ray absorptiometry 1 year after transplantation. Patients at high risk for bone loss (for example, patients receiving ≥ 5 mg of prednisone equivalent daily for > 3 months) can be screened earlier (for example, 3-6 months after HCT). Where indicated, bisphosphonates or other anti-resorptive agents (for example, calcitonin) can be used for prevention or treatment of osteoporosis in adult HCT recipients. Pediatric HCT recipients should be referred to a pediatric endocrinologist for evaluation and treatment of bone loss. There remain several areas of uncertainty that need further research in adult and pediatric HCT recipients, such as the optimal timing and frequency of screening for loss of bone mineral density, relationship of bone loss with risk of fractures, selection of appropriate patients for pharmacologic therapy, and optimal dosing schedule and duration of therapy with anti-resorptive agents.

Allogeneic hematopoietic cell transplant for multiple myeloma: Comparative results of planned therapy versus salvage therapy

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Background: Despite advances in therapy for multiple myeloma, the disease remains incurable using chemotherapy or immune-modulating agents alone. Several newer hematopoietic cell transplant (HCT) strategies including tandem HCT, and non- myeloablative (NMA) regimens have reported encouraging results. However, the appropriate timing for utilizing these strategies is not clear. Methods: We report outcomes in 51 patients with multiple myeloma who received an allogeneic HCT; either as salvage therapy (after failing a prior autologous HCT), n= 15 or as planned therapy, n= 36, between the years 1996 and 2008 at University of Minnesota. Results: Patients in salvage therapy group were significantly older than in planned therapy group (median age 58 versus 49 years) and had a longer interval from diagnosis to transplant (median 47 versus 10 months). Forty four patients received a HCT from a HLA-identical sibling. Five received umbilical cord blood (four in salvage therapy, one in planned therapy group) and two received unrelated donor HCT (one in each group). Thirteen patients in planned therapy group underwent a tandem transplant (planned autologous followed by NMA sibling HCT). All patients in salvage therapy group, and 50% in planned therapy group received NMA HCT. Patients in salvage therapy group were more heavily pre-treated, all having failed a prior autologous HCT. Complete response was seen in 34% versus 47% of recipients in the two groups, respectively. After a median follow-up of 24 and 41 months, similar relapse was seen, but transplant related mortality (TRM) was significantly higher in salvage therapy group, leading to significantly lower two year survival and disease free survival (DFS) in salvage group. Conclusions: Good overall survival and low transplant related mortality was seen in patients undergoing a planned allogeneic transplant. In heavily pre-treated patients, receiving allogeneic HCT as salvage therapy, despite lower relapse, the high TRM led to lower survival.

[Table: see text]

No significant financial relationships to disclose.

Difficult stem cell mobilization despite adequate CD34+ cell dose predicts shortened progression free and overall survival after autologous HSCT for lymphoma

Hematopoietic growth factors alone or in combination with myelosuppressive chemotherapy are used to mobilize peripheral blood stem cells for autologous transplantation. To identify characteristics of successful mobilization with granulocyte colony-stimulating factor (G-CSF) alone and to study the impact of immediate chemotherapy mobilization following G-CSF mobilization, we treated 175 chemotherapy sensitive lymphoma patients with G-CSF (G) mobilization and leukapheresis followed by chemotherapy plus G-CSF (CG) mobilization and leukapheresis and then autologous transplantation. Patients with stage I/II disease at diagnosis and < or =5 years from diagnosis were more likely to mobilize successfully with G-CSF alone (G). CG mobilization led to superior stem cell yields compared to the preceding mobilization with G (median 2.37 vs 1.37 ( x 10(6)CD34+ cells/kg); P<0.0001). Patients (n=58, 33%) with successful G-CSF mobilization (> or =2 x 10(6) CD34+ cells/kg) had quicker platelet recovery and improved progression free and overall survival compared to patients who had adequate collection only after chemotherapy mobilization or to those who failed to collect an adequate graft with either type of mobilization. The poor clinical outcome of patients with difficult mobilization using either method identifies them as a high-risk group who might benefit from alternative therapies.

Fludarabine vs cladribine plus busulfan and low-dose TBI as reduced intensity conditioning for allogeneic hematopoietic stem cell transplantation: a prospective randomized trial

Purine analogs are often used for conditioning preceding allogeneic hematopoietic stem cell transplantation (HCT). We prospectively tested fludarabine (Flu) 40 mg/m(2)/day x 5 days vs cladribine (Clad) 10 mg/m(2)/day x 5 days plus oral busulfan (1 mg/kg q6 h x 2 days) and total body irradiation 200 cGy in 32 recipients of matched sibling and unrelated donor (URD) HCT. Patients were similar in age (median 52 years), diagnosis, extensive pre-HCT therapy (56 vs 63%), and high-risk disease status (81 vs 93%). Neutrophil engraftment was prompt (median 11 vs 12 days), but early graft failure using Clad halted randomization. Platelet recovery was prompt (median Flu 18 vs Clad 24 days). Graft-versus-host disease (GVHD) after Flu vs Clad was similar; (acute grade II/IV 56 vs 69%, P=0.26; chronic 50 vs 31%, P=0.27). Nonrelapse mortality (Flu 25 vs Clad 38%, P=0.47) and progression-free survival at 3 years were similar as well. Multivariate analyses showed slightly, but not significantly lower relative risk (RR) of neutrophil engraftment with Clad (RR 0.6 (95% CI 0.2-1.3) P=0.16) and with URD RR 0.4 (0.2-1.0) P=0.04). Older patients with advanced hematologic malignancies achieve satisfactory outcomes using either of these reduced intensity conditioning regimens.

Recommended screening and preventive practices for long-term survivors after hematopoietic cell transplantation: joint recommendations of the European Group for Blood and Marrow Transplantation, Center for International Blood and Marrow Transplant Research, and the American Society for Blood and Marrow Transplantation (EBMT/CIBMTR/ASBMT)

More than 40,000 hematopoietic cell transplants (HCTs) are performed worldwide each year. With improvements in transplant technology, larger numbers of transplant recipients survive free of the disease for which they were transplanted. However, there are late complications that can cause substantial morbidity. Many survivors are no longer under the care of transplant centers and many community health-care providers may be unfamiliar with health matters relevant to HCT. The Center for International Blood and Marrow Transplant Research (CIBMTR), European Group for Blood and Marrow Transplantation (EBMT), and American Society for Blood and Marrow Transplantation (ASBMT) have developed these recommendations to offer care providers suggested screening and prevention practices for autologous and allogeneic HCT survivors.

Results of autologous and allogeneic hematopoietic cell transplant therapy for multiple myeloma

We compared the results of autologous and allogeneic peripheral blood hematopoietic cell transplant (HCT) in 87 patients with multiple myeloma using myeloablative preparative regimen. Autologous transplant (n=70) led to a lower 100-day transplant-related mortality (TRM) of 4% [0-9%] compared to 18% [0-36%] in allogeneic recipients (P=0.02). More frequent complete responses were seen in allogeneic recipients (64% [37-91%] vs 34% [23-45%] in autologous recipients, P=0.09). In autologous recipients, survival at 1 year was 86% [80-95%] and, it fell to 50% [47-75%] at 4 years, whereas in allogeneic recipients, survival at 1 and 4 years remained at 64% [40-87%]. In patients surviving more than one year, 4-year survival was superior in allogeneic (100%) vs autologous recipients (58% [41-75%], P=0.02). A trend toward higher relapse was seen in autologous transplant patients (73% [55-90%] vs 37% [11-63%] in allogeneic transplant patients, P=0.1). We observed good tolerance of myeloablative conditioning regimen followed by either autologous or allogeneic transplant. Although autologous HCT is associated with lower TRM, allogeneic HCT has acceptable TRM, and is more likely to provide a sustained response. Allogeneic HCT may be suitable in younger patients, soon after diagnosis, and in those with chemosensitive disease.

IL-2-based immunotherapy after autologous transplantation for lymphoma and breast cancer induces immune activation and cytokine release: a phase I/II trial

We determined the safety, immune activating effects, and potential efficacy of i.v. infusion of ex vivo interleukin-2 (IL-2) activated natural killer (NK) cells (part I) or IL-2 boluses (part II) during daily s.c. IL-2 administration following hematopoietic recovery from autologous transplantation. In all, 57 patients with relapsed lymphoma (n=29) or metastatic breast cancer (n=28) were enrolled. In part I of the study, 34 patients were enrolled at three dose levels of ex vivo IL-2-activated NK cells. Lymphaphereses were performed on days 28 and 42 of s.c. IL-2 administration. Following overnight ex vivo IL-2 activation of the pheresis product, the cells were reinfused the following day. In part II, 23 patients were enrolled at three dose levels of supplemental i.v. IL-2 bolus infusions, given on days 28 and 35 during s.c. IL-2 administration. Toxicities were generally mild, and no patient required hospitalization. Lytic function was markedly enhanced for fresh peripheral blood mononuclear cells (PBMNCs) obtained 1 day postinfusion of either IL-2-activated cells or IL-2 boluses. IL-2 boluses transiently increased the levels of IL-6, IFN-gamma, TNF-alpha and IL1-beta, with increases in IL-6 and IFN-gamma being dose dependent. A total of 37 patients (19 patients with lymphoma, 18 with breast cancer) treated with an optimum dose of post-transplant immunotherapy (defined as having received 1.75 x 10(6) IU/m(2)/day of s.c. IL-2 plus at least one of the planned ex vivo IL-2-activated cell infusions/IL-2 boluses) could be matched with controls from the Autologous Blood and Marrow Transplant Registry database. The matched-pairs analysis demonstrated no improvement in disease outcomes of survival and relapse. We conclude that IL-2-activated cells/IL-2 boluses can be safely administered, generate PBMNCs with enhanced cytotoxicity against NK-resistant targets, and increase cytokine levels. With this dose and schedule of administration of IL-2, no improvement in patient disease outcomes was noted. Alternative strategies will be needed to exploit the immunotherapeutic potential of IL-2-activated NK cells.

Transformed lymphoma: an Achilles' heel of non-Hodgkin's lymphoma

Transformed lymphoma has a reported incidence of 10-70% among patients with follicular lymphoma. Interpreting the wide-ranging estimates for incidence, survival, and effects of interventions from various studies is complicated by the use of different definitions of lymphoma transformation. Problems in defining histologic transformation will be addressed in this review. To date, there are no reliable markers of risk for transformation or factors predictive of survival. The prognosis for transformed lymphoma is generally poor, with most patients surviving only a few months, though some with limited disease that is chemosensitive may experience prolonged survival. Immunotherapy, particularly monoclonal antibodies and radioimmunoconjugates, holds promise but more experience is necessary. Approximately 200 patients are included in published series of autologous transplantation; of these, one-third remain disease free at 5 years, not dissimilar to reported outcomes for nontransformed disease. However, the treatment-related mortality is higher than in nontransformed disease, and there is a significant incidence of post-transplant myelodysplastic syndrome. The role of allogeneic transplant has yet to be pursued, but should be explored for its potential for a graft-versus-lymphoma effect. Advances in microarray gene analysis and biology may facilitate the understanding of mechanisms of transformation, development of a prognostic index and creation of tailored therapy.

Preclinical studies targeting normal and leukemic hematopoietic cells with Yttrium-90-labeled anti-CD45 antibody in vitro and in vivo in nude mice

A study was undertaken to investigate the suitability of using a high affinity (Kd = 1.1 nM) anti-CD45 monoclonal antibody for delivering the high energy beta-particle emitting isotope (90)Y to lymphohematopoietic target cells in vivo. The antibody, AHN-12, recognized the tyrosine phosphatase CD45 expressed on the surface of normal and malignant hematopoietic cells and studies showed that it reacted with both CD45-expressing normal peripheral blood cells and leukemia cells from patients. The antibody was readily labeled with (90)Y using the highly stable chelate 1B4M-DTPA and the radioimmunoconjugate was designated (90)Y-anti-CD45. The agent selectively bound to CD45(+) B cell line Daudi, but not CD45(-) control cells and significantly (p = 0.007) more bound to Daudi tumors growing in athymic nude mice than did a control non-reactive antibody. Moreover, biodistribution data correlated well to an anti-Daudi effect observed against established tumors in nude mice. The effect was dose dependent and irreversible with the best results in mice receiving a single dose of 137 microCi (90)Y-anti-CD45. These mice displayed a significantly (p < 0.0095) better anti-tumor effect than a control (90)Y-labeled antibody and survived over 135 days with no evidence of tumor. Histology studies showed no significant injury to kidney, liver, or small intestine even at 254 microCi, the highest dose tested. Because radiolabeled anti-CD45 antibody can be used to deliver radiation selectively to lymphohematopoietic tissue, these data indicate that this agent may be used to improve treatment of hematopoietic malignancies, particularly leukemia and lymphoma, when combined with hematopoietic stem cell transplantation in a future clinical trial.

Randomized clinical trial of ganciclovir vs acyclovir for prevention of cytomegalovirus antigenemia after allogeneic transplantation

Cytomegalovirus (CMV) disease remains a major cause of morbidity following allogeneic stem cell transplantation (SCT). In a prospective randomized trial, we tested prophylactic therapy with ganciclovir or acyclovir for patients at high risk of disease. Ninety-one CMV seropositive recipients of related (n = 53) and unrelated (n = 38) donor transplants were enrolled. All patients received intravenous (i.v.) ganciclovir 5 mg/kg every 12 h days -7 to -2, followed by acyclovir 10 mg/kg i.v. every 8 h from day -1 until neutrophil engraftment. Patients were then randomly assigned to either ganciclovir (n = 45) or acyclovir (n = 46) until day 100 post transplant. Any degree of antigenemia was treated with ganciclovir 5 mg/kg i.v. twice a day for 2 weeks, followed by 5 mg/kg i.v. each weekday for 6 weeks. At day 100, the cumulative incidence of antigenemia was 31% (95% CI 17-45%) for ganciclovir and 41% (95% CI 26-56%) (P = 0.22) for acyclovir prophylaxis, respectively. The assigned prophylaxis cohort did not predict for CMV antigenemia. The cumulative incidence of CMV disease at 12 months was 13% (95% CI 3-23%) and 17% (95% CI 6-28%) (P = 0.59) for the ganciclovir- and acyclovir-treated groups, respectively. An absolute neutrophil count (ANC) <or=1500 x 10(6)/l at randomization (P < 0.01) and grade II-IV acute graft-versus-host-disease (P = 0.01), but not the assigned prophylaxis cohort (P = 0.62), were independent risk factors for CMV disease. The incidence of fungal infections and renal insufficiency was similar across treatment groups; however, bacterial infections and secondary neutropenia occurred more frequently in the ganciclovir group. With our study powered to detect a 60% reduction in antigenemia with ganciclovir prophylaxis, we did not find a statistically significant difference between ganciclovir and acyclovir when used as part of an overall strategy for prevention of CMV antigenemia and disease in SCT, although fewer side-effects occurred with acyclovir treatment.

Autotransplants for Hodgkin's disease in first relapse or second remission: a report from the autologous blood and marrow transplant registry (ABMTR)

Although patients with relapsed Hodgkin's disease have a poor prognosis with conventional therapies, high-dose chemotherapy and autologous hematopoietic stem cell transplantation (autotransplantation) may provide long-term progression-free survival. We reviewed data from the Autologous Blood and Marrow Transplant Registry (ABMTR) to determine relapse, disease-free survival, overall survival, and prognostic factors in this group of patients. Detailed records from the ABMTR on 414 patients with Hodgkin's disease in first relapse (n = 295) or second complete remission (CR) (n = 119) receiving an autotransplant from 1989 to 1995 were reviewed. Median age was 29 (range, 7-64) years. Median time from diagnosis to relapse was 18 (range, 6-219) months; median time from relapse to transplant was 5 (range, <1-215) months. Most patients received high-dose chemotherapy without total body irradiation for conditioning (n = 370). The most frequently used high-dose regimen was cyclophosphamide, BCNU, VP-16 (CBV) (n = 240). The graft consisted of bone marrow (n = 246), blood stem cells (n = 112), or both (n = 56). Median follow-up was 46 (range, 5-96) months. One hundred-day mortality (95% confidence interval) was 7 (5-9)%. One hundred and sixty-five of 295 patients (56%) transplanted in relapse achieved CR after autotransplantation. Of these, 61 (37%) recurred. Twenty-four of 119 patients (20%) transplanted in CR recurred. The probability of disease-free survival at 3 years was 46 (40-52)% for transplants in first relapse and 64 (53-72)% for those in second remission (P < 0.001). Overall survival at 3 years was 58 (52-64)% after transplantation in first relapse and 75 (66-83)% after transplantation in second CR (P < 0.001). In multivariate analysis, Karnofsky performance score <90% at transplant, abnormal serum LDH at transplant, and chemotherapy resistance were adverse prognostic factors for outcome. Progression of Hodgkin's disease accounted for 69% of all deaths. Autotransplantation should be considered for patients with Hodgkin's disease in first relapse or second remission. Future investigations should focus on strategies designed to decrease relapse after autotransplantation, particularly in patients at high risk for relapse.

Matched-pair analysis of peripheral blood stem cells compared to marrow for allogeneic transplantation

We performed a case-control analysis of 42 patients with advanced leukemia or MDS comparing peripheral blood stem cell (PBSC) with marrow grafts (BMT) from HLA-matched sibling donors. PBSC were mobilized with G-CSF (7.5 microg/kg/day) and yielded a median of 6.7 x 10(6) CD34+ cells/kg (range, 1.6-15.0) and 2.7 x 10(8) CD3+ cells/kg (range, 1.1-7.1) vs marrow grafts with a median of 2.0 x 10(8) nucleated cells/kg (range, 1.8-2.2). Recovery was significantly faster after PBSCT compared to BMT, with a median of 17 (range, 12-26) vs 26 (range, 16-36) days, respectively, to neutrophils >0.5 x 10(9)/l (P < 0.01), and 22 (range, 12->60) vs 42 (range, 18->60) days, for platelet recovery (P < 0.01). Transplantation of >/=7 x 10(6) CD34+ cells/kg accelerated recovery to >20 x 10(9) l platelets; median 17 days (range, 12-19) vs 23 days (range, 17-36) for those receiving <7 x 10(6)/kg (P = 0.01). PBSC and marrow recipients had similar risks of grades II-IV or III-IV acute GVHD or extensive chronic GVHD (all P > 0.3). At 1 year after PBSCT and BMT, the risk of relapse was 41% and 32%, respectively (P = 0.47), and the probability of survival was 46% and 48%, respectively (P = 0.70). HLA-matched sibling PBSCT resulted in faster neutrophil and platelet engraftment compared to BMT, with no subsequent differences in acute or chronic GVHD, relapse or survival. A minimum of 7 x 10(6) CD34+ cells/kg in PBSC grafts may be required for very rapid platelet engraftment. Bone Marrow Transplantation (2000) 26, 723-728.

Human cytomegalovirus immediate early proteins upregulate endothelial p53 function

Infected endothelial cells are found to be resistant to apoptosis possibly mediated by p53 cytoplasmic sequestration. We explored whether the immediate early 84 kDa protein (IE84) of cytomegalovirus (CMV) is responsible for p53 cytoplasmic sequestration. The endothelial cells were transfected with plasmids containing IE1 and 2 coding regions which are known to synthesize IE84 and 72 proteins. Our study found that p53 expression was significantly elevated in endothelial cells transfected with IE1 and 2 plasmids. However, p53 was only found in the nucleus rather than sequestered in the cytoplasm. We have demonstrated that IE84 and 72 are not responsible for p53 dysfunction caused by CMV infection, rather they upregulate p53 function and promote endothelial apoptosis.

Enhancement of the anti-tumor activity of a peripheral blood progenitor cell graft by mobilization with interleukin 2 plus granulocyte colony-stimulating factor in patients with advanced breast cancer

OBJECTIVE

Autologous interleukin 2 (IL-2)-activated natural killer (NK) cells kill a broad spectrum of tumor targets, including breast cancer. We hypothesized that mobilization with IL-2 and granulocyte colony-stimulating factor (G-CSF) for collection of peripheral blood progenitor cells (PBPC) may enhance the anti-tumor activity of the graft in autograft recipients. We determined the dose-limiting toxicity and maximum tolerated dose of subcutaneous IL-2 given with G-CSF for PBPC mobilization, the ability of IL-2 + G-CSF mobilized stem cells to reconstitute hematopoiesis, and the in vitro immunologic function of the graft in patients with advanced breast cancer. MATERIALS AID METHODS: Forty-three women with stage IIIA/B or metastatic breast cancer underwent mobilization of PBPC with IL-2 administered subcutaneously for 14 days along with G-CSF for the latter 7 days. IL-2 was given in a dose-escalated manner, with the maximum tolerated dose determined to be 1.75 x 10(6) IU/m(2)/day. Fifteen women with stage IIIA/B or metastatic breast cancer underwent G-CSF mobilization alone and served as a control group.

RESULTS

[corrected] Fifty-two percent of the patients mobilized with 1L-2 at the maximum tolerated dose reached the target number of CD34(+) cells for transplantation with three aphereses compared to 93% of control patients who were mobilized with G-CSF alone. [corrected] There was no significant impact on time to engraftment of neutrophils or platelets using either mobilization regimen. The addition of subcutaneous IL-2 to mobilization increased the cytotoxicity of IL-2-activated mononuclear cells from the PBPC product against the breast cancer cell target, MCF-7, and increased the percentage of NK cells and activated T cells in the PBPC product. The enhanced NK cell number was sustained in the early posttransplant period.

CONCLUSIONS

[corrected] IL-2 + G-CSF mobilization is safe, may lead to a more immunologically functional graft without impairing hematologic recovery, and thus merits further exploration to evaluate the clinical anti-tumor efficacy of these immunocompetent grafts. [corrected] Limitations of this combined approach to stem cell mobilization include a decrease in the number of CD34(+) cells mobilized with the combined cytokines and the short duration of the increased number of anti-tumor effector cells after transplant.

Natural killer cell cytotoxicity of breast cancer targets is enhanced by two distinct mechanisms of antibody-dependent cellular cytotoxicity against LFA-3 and HER2/neu

Treatment of advanced breast cancer with autologous stem cell transplantation is limited by a high probability of disease relapse. In clinical trials, interleukin 2 (IL-2) alone can expand natural killer (NK) cells in vivo and increase their cytotoxic activity against breast cancer cell lines, but this increase is modest. Understanding the mechanisms that mediate NK cell lysis of breast cancer targets may lead to improvements of current immunotherapy strategies. NK cells from normal donors or patients receiving subcutaneous IL-2 were tested in cytotoxicity assays against five breast cancer cell lines. The role of adhesion molecules and antibodies that interact through Fc receptors on NK cells was explored. NK cell lysis of breast cancer targets is variable and is partially dependent on recognition through ICAM-1 and CD18. While blocking CD2 slightly decreased cytotoxicity, contrary to expectations, an antibody against CD58 (the ligand for CD2), failed to block killing and instead mediated an increased cytotoxicity that correlated with target density of CD58. The CD58 antibody-enhanced killing was dependent not only on FcRgammaIII but also on CD2 and ICAM-1/CD18. To further elucidate the mechanism of this CD58 antibody-dependent cellular cytotoxicity (ADCC), another antibody was tested. Trastuzumab (Herceptin), a humanized antibody against HER2/neu, mediated potent ADCC against all the HER2/neu positive breast cancer targets. Unlike CD58 antibody-mediated ADCC, Herceptin ADCC was minimally affected by blocking antibodies to CD2 or ICAM-1/CD18, which suggests a different mechanism of action. This study shows that multiple mechanisms are involved in NK cell lysis of breast cancer targets, that none of the targets are inherently resistant to killing, and that two distinct mechanisms of ADCC can target immunotherapy to breast cancer cells.

A novel four-drug ablative regimen with hemopoietic stem cell rescue for patients with breast cancer: a phase II study

High-dose chemotherapy and autologous hemopoietic stem cell transplantation (HSCT) may provide durable progression-free survival in some patients with stage IV breast cancer (S4Brca). We have studied a new four-drug intensive preparative regimen with HSCT in a group of 158 women with S4Brca to define the risk and potential benefit of this regimen in this patient population. From May 1988 through May 1997, 158 women with S4Brca at a single center were treated with cisplatin, etoposide, thiotepa, and cyclophosphamide (PETCy) plus autologous HSCT Eligible patients were also treated with posttransplant involved-field radiation therapy. Patients with estrogen-receptor positive tumors not previously treated with tamoxifen also received this therapy for 5 years following transplantation. All patients experienced significant toxicity requiring blood-product support and parenteral nutrition. Eighteen patients (11%) died of regimen-related toxic events. With a median follow-up of 540 days for surviving patients, a retrospective Kaplan-Meier analysis projects an overall survival of 38+/-8.5% (95% CI) at 890 days with a maximum follow-up of 8.8 years. For 52 patients in sensitive relapse, the median event-free survival time is 767 days, with 46.2+/-15.3% (95% CI) predicted to be alive at 884 days with a maximal follow-up of almost 9 years. Nearly one-half of patients in this study with S4Brca in sensitive relapse have experienced durable remissions following PETCy ablation and HSCT. Although toxicity is significant, the PETCy regimen produces a favorable balance between efficacy (event-free survival) and treatment failure (relapse + regimen-related toxic death) compared with published results. These data suggest that within the high-dose range for preparative therapy, a steep dose-response may exist for breast cancer. Trials comparing the dose intensity of preparative regimens are warranted.

Intercellular adhesion molecule-1 expression in endothelial cells is activated by cytomegalovirus immediate early proteins

BACKGROUND

Human cytomegalovirus (HCMV) infection is associated with allograft vasculopathy and rejection. One potential mechanism is vascular injury from immunologically mediated processes. HCMV infection has been shown to increase the constitutive expression of intercellular adhesion molecule-1 (ICAM-1). The objective of this study was to determine the molecular basis of HCMV enhanced ICAM-1 gene expression in endothelial cells using human umbilical vein endothelial cells (HUVECs) as a model.

METHODS

HUVECS were infected with HCMV virus and the level of ICAM-1 mRNA determined over time. HUVECS were then transiently transfected with plasmid constructs containing ICAM-1 and HCMV immediate early (IE) gene sequences and the effect of IE proteins on ICAM-1 promoter expression determined. Antibodies to cytokines known to be affected by HCMV IE proteins or to modulate ICAM-1 expression were added to determine if cytokines were mediating ICAM-1 expression.

RESULTS

Infection of HUVECs with HCMV resulted in a rapid rise in ICAM-1 mRNA levels, suggesting that the viral IE proteins were involved in gene activation. The HCMV IE1 and IE2 proteins synergistically activated both transfected and endogenous ICAM-1 gene expression. The addition of antibodies to interleukin-1, tumor necrosis factor-a, transforming growth factor-beta, or interleukin-6 had no effect on the IE protein-mediated increase in ICAM-1 expression. Deletion analysis of the ICAM-1 gene promoter revealed that a minimum of 370 base pairs of 5' flanking sequences was required for maximal transactivation by IE proteins; mutation analysis showed that an NFkappaB site at base pairs -187 to -178 was not required for promoter activation.

CONCLUSIONS

These results demonstrate that HCMV regulates the heterologous ICAM-1 gene promoter in endothelial cells not via cellular cytokine production, but rather by a direct effect of IE proteins, and supports a model in which HCMV IE gene products interact with ICAM-1 promoter elements to increase gene expression.

Therapy of patients with T-cell lymphomas and leukemias using an anti-CD7 monoclonal antibody-ricin A chain immunotoxin

Anti-CD7-dgA, DA7, consists of deglycosylated ricin A chain coupled to a mouse monoclonal anti-human CD7 antibody. This study determined the maximally tolerated dose (MTD) of this immunotoxin administered as a one hour infusion over five days to 11 patients with T-cell lymphoma (>30% CD7+ malignant cells). The MTD was 0.2 mg/kg/day or 1 mg/kg/120 hours (maximal toxicity grade 3) with vascular leak syndrome (VLS) as dose-limiting toxicity (DLT). Predictors of severe VLS included age and absence of circulating lymphoma cells. Two partial responses and one minimal response were seen. Patients with minimal lymphoma burden or T-cell large granular lymphocyte (LGL) leukemia showed the best responses. The mean maximal serum concentration of immunotoxin at the MTD was 2.5 ug/ml. The mean alpha-phase half-life was 1.5 hours and the mean beta-phase half-life was 8 hours. Repeated dosing had minimal effects on either peak serum immunotoxin concentrations or serum half-lives. While human antimouse antibodies were observed, they were low in concentration (<55 ng/ml). Human anti-ricin antibody was elevated in one patient (190 ng/ml). VLS presented with hypoalbuminemia, dyspnea, pulmonary edema, aphasia, and peripheral edema and cleared over a two week period. Serum fibronectin levels were measured in three patients and were very low in one patient who developed VLS. No specific binding of DA7 immunotoxin was seen with vascular endothelium in various human tissues.

Low dose subcutaneous interleukin-2 after autologous transplantation generates sustained in vivo natural killer cell activity

Autologous transplantation can induce extended remission in some patients with advanced breast cancer and lymphoma yet nearly 80% and 50%, respectively, will ultimately relapse. In vitro studies suggest that activated natural killer cells (NK) mediate lytic activity against breast cancer and lymphoma cell lines. Therefore, immunotherapy with interleukin-2 (IL-2, Amgen) to activate NK may improve long-term disease-free survival when administered in a post-transplant minimal residual disease setting. To determine the feasibility of administering IL-2 and activation of NK post-transplant, twelve patients (6 breast cancer, 6 lymphoma) were enrolled on a phase I dose escalation study after autologous transplantation (median day + 94, range 50-166). IL-2 was self administered at 0.25 x 10(6) (n = 6) or 0.5 x 10(6) (n = 6) U/m2/day subcutaneously for 84 consecutive days. The best tolerated dose was 0.25 x 10(6) U/m2/day (75% of planned doses given vs. 48% at the higher dose). Dose limiting toxicity occurred in 6 patients (n = 2 at 0.25 x 10(6) U/m2/day, n = 4 at 0.5 x 10(6) U/m2/day) consisting of decreased performance status (n = 2), thrombocytopenia (n = 3, 1 at the lower dose), and mild neutropenia (n = 1 at the lower dose). However, all symptoms resolved within a week following discontinuation of IL-2 and no patient required hospitalization. Circulating soluble IL-2 receptor levels were significantly increased in all patients receiving IL-2. Patients receiving at least 28 days of IL-2 exhibited a greater than 10-fold increment in circulating CD56+bright/CD3- NK. Furthermore, lytic function was increased against NK resistant targets, MCF-7 (breast cancer), and Raji (lymphoma). In vivo IL-2 primed NK cells obtained by lymphapheresis were activated in large-scale ex vivo incubation in high dose IL-2 (1,000 U/mL) at high cell density (10 x 10(6)/mL), in gas permeable bags, and using serum-free media. NK lytic function against MCF-7 and Raji targets was further enhanced. We conclude that low dose subcutaneous IL-2 based immunotherapy is feasible, relatively safe, can be administered in an outpatient setting and hypothesize that additional ex vivo incubation in IL-2 may be used to generate NK cells with potent antitumor effects in vivo.

Cytoplasmic sequestration of p53 in cytomegalovirus-infected human endothelial cells

Human umbilical vein endothelial cells were infected with human cytomegalovirus (HCMV) at a multiplicity of infection of 0.1 plaque-forming unit/cell and remained > 95% viable even after 10 days of infection. To induce apoptosis, control human umbilical vein endothelial cells and cells infected with HCMV for 3, 5, and 7 days were serum starved for 48 hours. Almost one-half of the uninfected cells lost viability after 48 hours of serum starvation whereas HCMV-infected cells were virtually unaffected (< 20% death, P < 0.05). Uninfected cells showed typical hallmarks of apoptosis, including unique morphological changes and DNA laddering. HCMV-infected cells, concomitant with their resistance to serum-starvation-induced death, displayed almost none of these characteristics. Active replication of HCMV was necessary for the anti-apoptotic effect, as cells treated with ultraviolet light-inactivated virus were not protected. p53, the G1/S phase cell cycle brake protein, was elevated in HCMV-infected cells. However, rather than accumulating in the nucleus, immunofluorescent and Western blot studies demonstrated remarkable and predominant cytoplasmic sequestration of p53 in HCMV-infected endothelial cells. Although HCMV proteins have already been shown to block apoptosis, we suggest that the aberrant subcellular pattern of p53 is the disturbed cellular mechanism that may be responsible for the anti-apototic properties of HCMV-infected cells. The selective resistance to apoptosis can be important during HCMV replication and may explain the oncogenic potential of HCMV as well as its pathogenic role in intimal-proliferation-mediated vascular diseases.

Laboratory preparation of a deglycosylated ricin toxin A chain containing immunotoxin directed against a CD7 T lineage differentiation antigen for phase I human clinical studies involving T cell malignancies

An immunotoxin consisting of a monoclonal antibody specific for CD7, a cell surface determinant expressed on T acute lymphocytic leukemia (T-ALL) blast cells, was linked to the potent plant toxin deglycosylated ricin toxin A chain (dgRTA) and is currently under evaluation in phase I clinical trials. Scale-up production of this immunotoxin, called DA7, was simplified using a two-step purification protocol that resulted in a highly purified immunotoxin meeting FDA criteria for IND approval. The anti-CD7 antibody, 3Ale, an IgG2b, was coupled to toxin using two different heterobifunctional cross-linkers, (1) N-succinimidyl-3-(2-pyridyl-dithiolproprionate) (SPDP), considered a standard croslinker and (2) 4-succinimidyloxycarbonyl-alpha-methyl-alpha-(2-pyridyldithio)tolu ene (SMPT), designed to hinder the in vivo breakdown of the toxin/antibody disulfide bond. Since experiments revealed that SPDP-DA7 had similar pharmacokinetics and biodistribution in mice and higher yields than DA7 made with a hindered cross-linker, SPDP-DA7 was scaled up for clinical study. Yield of SPDP-DA7 was 25% relative to starting material. Fractions were collected containing a toxin: antibody ratio of 1:1 to 4:1 rather than only a 1:1 ratio since studies showed that this heterogenous fraction was just as toxic to proliferating CD7-expressing leukemia cells as a homogeneous 1:1 fraction. In vitro, the concentration of heterogenous SPDP-DA7 selectively inhibiting 50% activity (IC50) of the CD7+ CEM cell line was 0.01 microgram/ml to 0.05 microgram/ml for inhibiting activated T cells or T cell lines. In vivo, SPDP-DA7 showed a significant anti-tumor effect against CEM cells administered to scid/scid mice, but even more importantly was effective against primary T cell leukemias taken from patients and injected into scid/scid mice.

Autologous stem cell transplantation for refractory and relapsed Hodgkin's disease: factors predictive of prolonged survival

We analyzed patient, disease, and treatment related factors associated with long-term disease-free survival (DFS) in 62 patients with refractory or recurrent Hodgkin's disease treated with high-dose cyclophosphamide (6000 mg/m2), carmustine (BCNU; 300 mg/m2), and etoposide (900 mg/m2) (CBV) followed by autologous stem cell transplantation. There were no deaths resulting from toxicity of the preparative regimen, and all patients survived the peritransplant period. At 28 days post-transplant, the complete response (CR) rate was 76%. Patients who achieved a CR had a 50% estimated 3-year DFS (95% CI, 35-64%). Twenty-three (37%) patients remain in continuous clinical remission 1.3 to 7.7 years (median 3.8 years) after transplantation. In a univariate analysis, factors significantly associated with improved DFS included absence of B symptoms (fever, night sweats and unexplained weight loss) at transplant, response to pre-transplant salvage chemotherapy, less tumor bulk at time of transplant, and fewer prior treatment regimens. Stepwise multivariate analysis showed that the absence of B symptoms at time of transplant was independently and significantly associated with improved DFS after transplantation. CBV with autologous stem cell support can produce durable remissions with acceptable toxicity in a substantial proportion of patients who are asymptomatic at time of transplant. Earlier application of transplantation or development of additional effective antineoplastic modalities will be required to improve the results of transplantation for patients with advanced Hodgkin's disease.

Extrapyramidal symptoms in a BMT recipient with hyperintense basal ganglia and elevated manganese

Neurologic syndromes attributed to conditioning or medications have been reported in BMT recipients. A patient is presented who developed extrapyramidal symptoms on day +56 after allogeneic BMT. Brain magnetic resonance images of this patient demonstrated hyperintense basal ganglia, which has been associated with manganese (Mn) toxicity. The patient had received total parenteral nutrition (TPN) with standard trace element supplementation and had been cholestatic. Serum Mn was elevated, and continued to be so 5 months after BMT, long after discontinuation of TPN. Cholestatic patients and those on long-term TPN have been found to have high blood or serum levels of Mn, but generally are asymptomatic. When other cholestatic BMT patients were reviewed, all had elevated serum Mn. Manganese supplementation in TPN requires evaluation for BMT recipients.

The human leukocyte antigen A2 interferon-stimulated response element consensus sequence binds a nuclear factor required for constitutive expression

Both constitutive and interferon-inducible enhancer-like elements have been identified previously in the promoter of human leukocyte antigen (HLA) class I genes. One of these sites is termed the interferon-stimulated response element (ISRE). We have tested the function of an ISRE consensus sequence in the human HLA class I gene HLA-A2 and confirmed previous studies that showed that the HLA-A2 ISRE consensus sequence does not mediate a response to interferons. However, deletion of the ISRE consensus sequence caused a several-fold reduction in the constitutive expression of the HLA-A2 gene in K562 and Jurkat cells. Mobility shift assays performed with the HLA-A2 ISRE revealed the presence of a constitutive binding protein (ISRE/CBP). This protein binds specifically to the HLA-A2 ISRE sequence, and binding is not efficiently competed by the ISRE sequences of the HLA-B7 or ISG54 genes. Substitution of the HLA-B7 or ISG54 ISRE sequences for the HLA-A2 ISRE sequence caused a severalfold reduction in the constitutive expression of the HLA-A2 gene. Mass determinations showed the ISRE/CBP to be 105 kDa, different than any previously characterized ISRE binding proteins. We propose that ISRE/CBP is a novel positive transcriptional regulatory factor for the HLA-A2 gene that may contribute to the differential expression of HLA-A versus HLA-B genes.

Only the HLA class I gene minimal promoter elements are required for transactivation by human cytomegalovirus immediate early genes

The immediate early (IE) genes of human cytomegalovirus (HCMV) are expressed in lymphocytes and are known to transactivate both viral and cellular promoters. The mechanism by which IE gene products of HCMV transactivate expression of the HLA A2 gene promoter in Jurkat cells, a T-lymphocyte cell line, was investigated. Transient expression assays were performed using plasmids containing the HLA A2 promoter-regulatory region linked to the bacterial chloramphenicol acetyltransferase (CAT) gene and a plasmid expressing the CMV IE genes. The upregulation of the HLA A2 promoter by HCVM IE gene products was shown not to be secondary to either interferon-gamma or -alpha. Previously described MHC class I regulatory or enhancer elements such as the interferon-stimulated response element (ISRE), NF-kappa B and H2TF1 binding sequences, and the interferon consensus sequence (ICS) were not required for transactivation of the A2 promoter. Rather, the only known regulatory elements in the HLA A2 promoter necessary for both basal expression and transactivation by HCVM IE gene products are the CCAAT box and TATA box motifs. These results support a model in which HCVM IE gene products act through the minimal HLA A2 promoter elements to increase gene expression.

Etoposide in combination as first-line chemotherapy for advanced Hodgkin disease. A Cancer and Leukemia Group B study

BACKGROUND

In a pilot study, Cancer and Leukemia Group B (CALGB) incorporated etoposide into primary combination therapy for advanced Hodgkin disease.

METHODS

Thirty-six evaluable patients were treated with two or three courses of methotrexate, vincristine, prednisone, leucovorin, etoposide, and cyclophosphamide (MOPLEC), and then treated with five to seven additional courses of a known "curative" regimen: nitrogen mustard, vinblastine, prednisone, and procarbazine (MVPP).

RESULTS

After treatment with MOPLEC, there were 16 complete responders (44%) and 18 partial responders (50%). One patient had progressive disease and one patient was taken off study after an anaphylactic reaction to etoposide. After completing the entire protocol, 32 patients achieved complete remission (CR) (89%) and 3 achieved partial remission (PR) (8%). Five CR patients have relapsed and three additional patients have died in CR without recurrence. At 36 months, the estimated failure-free survival is 61% and overall survival is 72%.

CONCLUSIONS

This combination, which includes etoposide, is active for the primary treatment of advanced Hodgkin disease.

Cytomegalovirus infection presenting as polyarticular arthritis following autologous BMT

A 39-year-old woman developed polyarticular arthritis secondary to cytomegalovirus (CMV) infection following an autologous BMT. Active CMV infection was documented by identification of CMV in cultures from synovial fluid and urine. Treatment with a combination of ganciclovir and intravenous immunoglobulin resulted in resolution of symptoms. CMV infection should be considered as a possible etiology of arthritis following transplantation.

BVAC ablative chemotherapy followed by autologous bone marrow transplantation for patients with advanced lymphoma

Forty-one consecutive patients with lymphoma resistant to conventional combination chemotherapy have been entered into a study in which chemo-ablative therapy and autologous marrow rescue were used with curative intent. The actuarial proportion of 20 patients with Hodgkin's lymphoma remaining alive and free of recurrent disease is 49%, while that for 21 patients with non-Hodgkin's lymphoma is 41%. Our clinical approach to these patients involved a strategy whereby lymphomatous nodes greater than 2 cm in diameter that persisted despite salvage chemotherapy were given boost radiation therapy immediately before chemo-ablation. However, patients with this variable had a significantly lower survival due to septic complications rather than recurrent disease. We conclude that the treatment strategy used in this study with some modification may improve further on the already high probability of long-term disease-free survival experienced by this group of patients.

Disseminated Fusarium infections in patients following bone marrow transplantation

Intensive immunosuppressive therapy and broad spectrum antibiotics predispose cancer patients to opportunistic fungal infections. Fusarium has rarely been reported as a pathogen in immunocompromised patients, but is almost uniformly fatal. Only six cases of disseminated Fusarium infection have been described in patients following bone marrow transplantation (BMT). We report here two additional cases. Fusarium infection initially presented with pyomyositis in one patient and with embolic skin lesions in another following T cell-depleted BMT. Both patients died with active Fusarium infection despite an extensive course of amphotericin B, rifampicin and granulocyte transfusions. From this experience and from a review of the literature, Fusarium infections appear to be increasing in prevalence as significant pathogens in immunocompromised hosts and are resistant to many conventional forms of therapy.

Butyrate induces selective transcriptional activation of a hypomethylated embryonic globin gene in adult erythroid cells

An animal model of hemoglobin switching has been developed in which anemic adult chickens are treated with 5-azacytidine and sodium butyrate or alpha-aminobutyric acid, thereby resulting in activation of the embryonic rho-globin gene in adult erythroid cells. In vitro nuclear runoff transcription assays using erythroid nuclei from treated birds show that the mechanism of activation of the rho-globin gene is transcriptional whereas no transcriptional activation of the embryonic epsilon-globin gene occurs. The action of 5-azacytidine appears to be as an inhibitor of DNA methylation because other S-phase active cytotoxic drugs, when substituted for 5-azacytidine, do not cause demethylation of the embryonic globin genes, nor do they allow transcriptional activation to occur. Embryonic rho-globin gene activation in this model is not due to selection of primitive erythroid cells since a subpopulation of primitive erythroid cells is not evident either morphologically or when cells are probed for embryonic and adult globin RNA by in situ hybridization. These studies show that demethylation by 5-azacytidine is a prerequisite but not sufficient cis-regulatory event for a high level of transcriptional activation of the embryonic rho-globin gene in adult erythroid cells in vivo. The possible basis for the selective transcriptional activation by sodium butyrate in this system is discussed.

Acute graft-versus-host disease resulting from normal donor blood transfusions

2 fatal cases of graft-versus-host disease (GvHD) occurred following blood product transfusions given to patients receiving standard chemotherapy for Hodgkin's disease. GvHD was established by HLA typing, clinical course, and compatible skin biopsy. 23 cases of GvHD following transfusion of blood products from normal donors are also reviewed. It should be suspected when fever or rash appear 1-2 weeks after transfusion of unirradiated blood products into a compromised host or when pancytopenia following chemotherapy is prolonged or unexpectedly severe. Prevention of GvHD by irradiation of granulocytes, platelets and packed red blood cells given to immunosuppressed patients is recommended to prevent this often fatal disease.