Effect of age on outcome of reduced-intensity hematopoietic cell transplantation for older patients with acute myeloid leukemia in first complete remission or with myelodysplastic syndrome

PURPOSE Acute myelogenous leukemia (AML) and myelodysplastic syndrome (MDS) primarily afflict older individuals. Hematopoietic cell transplantation (HCT) is generally not offered because of concerns of excess morbidity and mortality. Reduced-intensity conditioning (RIC) regimens allow increased use of allogeneic HCT for older patients. To define prognostic factors impacting long-term outcomes of RIC regimens in patients older than age 40 years with AML in first complete remission or MDS and to determine the impact of age, we analyzed data from the Center for International Blood and Marrow Transplant Research (CIBMTR). PATIENTS AND METHODS We reviewed data reported to the CIBMTR (1995 to 2005) on 1,080 patients undergoing RIC HCT. Outcomes analyzed included neutrophil recovery, incidence of acute or chronic graft-versus-host disease (GVHD), nonrelapse mortality (NRM), relapse, disease-free survival (DFS), and overall survival (OS). RESULTS Univariate analyses demonstrated no age group differences in NRM, grade 2 to 4 acute GVHD, chronic GVHD, or relapse. Patients age 40 to 54, 55 to 59, 60 to 64, and > or = 65 years had 2-year survival rates as follows: 44% (95% CI, 37% to 52%), 50% (95% CI, 41% to 59%), 34% (95% CI, 25% to 43%), and 36% (95% CI, 24% to 49%), respectively, for patients with AML (P = .06); and 42% (95% CI, 35% to 49%), 35% (95% CI, 27% to 43%), 45% (95% CI, 36% to 54%), and 38% (95% CI, 25% to 51%), respectively, for patients with MDS (P = .37). Multivariate analysis revealed no significant impact of age on NRM, relapse, DFS, or OS (all P > .3). Greater HLA disparity adversely affected 2-year NRM, DFS, and OS. Unfavorable cytogenetics adversely impacted relapse, DFS, and OS. Better pre-HCT performance status predicted improved 2-year OS. CONCLUSION With these similar outcomes observed in older patients, we conclude that older age alone should not be considered a contraindication to HCT.

Five-year follow-up of patients with advanced chronic lymphocytic leukemia treated with allogeneic hematopoietic cell transplantation after nonmyeloablative conditioning

PURPOSE

We reported encouraging early results of allogeneic hematopoietic cell transplantation (HCT) after nonmyeloablative conditioning in 64 patients who had advanced chronic lymphocytic leukemia (CLL). Here, we have extended the follow-up to a median of 5 years and have included data on an additional 18 patients.

PATIENTS AND METHODS

Eighty-two patients, age 42 to 72 years, who had fludarabine-refractory CLL were conditioned with 2 Gy total-body irradiation alone or combined with fludarabine followed by HCT from related (n = 52) or unrelated (n = 30) donors.

RESULTS

Complete remission (CR) and partial remission were achieved in 55% and 15% of patients, respectively. Higher CR rates were noted after unrelated HCT (67% v 48%). The 5-year incidences of nonrelapse mortality (NRM), progression/relapse, overall survival, and progression-free survival were 23%, 38%, 50%, and 39%, respectively. Among 25 patients initially reported in CR, 8% relapsed and 8% died as a result of NRM, whereas 84% have remained alive and in CR. Among 14 responding patients who were tested and who had molecular eradication of their disease, two died as a result of NRM, two relapsed, and 10 have remained negative. At 5 years, 76% of living patients were entirely well, whereas 24% continued to receive immunosuppression for chronic graft-versus-host disease; the median performance status in each group was 100% and 90%, respectively. Lymphadenopathy > or = 5 cm, but not cytogenetic abnormalities at HCT, predicted relapse. In a risk-stratification model, patients who had lymphadenopathy less than 5 cm and no comorbidities had a 5-year OS of 71%.

CONCLUSION

Nonmyeloablative HCT resulted in a median survival of 5 years for patients who had fludarabine-refractory CLL with sustained remissions and in the continued resolution of chronic graft-versus-host disease in surviving patients.

Final analysis of the phase II, randomized, double-blind, placebo-controlled trial of single dose velafermin (CG53135–05) for the prevention of oral mucositis

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Background: Oral mucositis (OM) is a commonly occurring side effect of high-dose chemotherapy (HDCT) in patients (pts) undergoing autologous hematopoietic stem cell transplant (AHSCT). Velafermin, recombinant human fibroblast growth factor 20, is being investigated for prevention of OM. Velafermin promotes epithelial and mesenchymal cell proliferation in vitro and in vivo. Methods: A phase II trial was conducted to evaluate safety, efficacy, and pharmacokinetics (PK) of velafermin. Inclusion criteria: pts undergoing HDCT and AHSCT with or without total body irradiation (TBI) were enrolled. Velafermin at 0.03, 0.1, or 0.2 mg/kg or placebo was administered as single dose IV at 24h after stem cell infusion. Safety and PK were assessed. Pts were scored daily for presence of OM using the WHO grading scale. The primary endpoint was the incidence of Grade 3/4 OM. Results: A total of 212 pts were randomized to either placebo (n=51) or velafermin at 0.03 (n=50), 0.1 (n=56), or 0.2 (n=55) mg/kg (intent-to-treat or ITT sample). 206 pts (97%) received study drug or placebo. Pt diagnoses included multiple myeloma (57%), non-Hodgkin’s (25%), or Hodgkin’s (11%) lymphoma and 13 pts (6%) received TBI as part of the conditioning regimen. The Grade 3/4 OM incidence rates (%) in the placebo or velafermin arms (0.03, 0.1, and 0.2 mg/kg) were 37, 18, 38, and 36, respectively. The primary analysis of dose dependent reduction of severe OM was not statistically significant (p = 0.549). However, velafermin at 0.03 mg/kg did reduce the incidence of Grade 3/4 OM when compared to placebo alone (p = 0.031). Duration of Grade 3/4 OM was reduced significantly in the 0.03 mg/kg when every pt was evaluated or in the 0.1 mg/kg dose when only pts with Grade 3/4 OM were included in the analysis (p = 0.037 and 0.014, respectively). A total of 5 related SAEs (3 in 0.1 mg/kg, 1 in 0.03 mg/kg, and 1 in placebo cohort) occurred within 4hr of study drug infusion. All symptoms were transient. Conclusion: Single dose velafermin at 0.03mg/kg is may be active in reducing CT induced severe OM in AHSCT pts. Safety profile supports continuing study to define the optimal dose for prevention of severe OM. A new Phase II study will be conducted to confirm velafermin activity at 0.03mg/kg dose.

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The effect of prior exposure to imatinib on transplant-related mortality

BACKGROUND AND OBJECTIVES

Imatinib is an effective treatment for chronic myeloid leukemia (CML) and Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL). However, relapse is common in patients with advanced or high risk disease. Such patients may be eligible for allogeneic stem cell transplantation (SCT), raising the question whether imatinib therapy may compromise the outcome of subsequent SCT.

DESIGN AND METHODS

We retrospectively analyzed 70 patients with CML and 21 with Ph+ ALL who had received imatinib prior to SCT. Data were retrieved by directly contacting centers. Multivariate analysis was used to define factors associated with major outcomes (engraftment, graft-versus-host disease, relapse, non-relapse mortality) in addition to descriptive statistics. For the CML patients major outcomes were compared with those of historical controls drawn from the EBMT registry.

RESULTS

At SCT, 44% of CML patients were in accelerated phase or blast crisis and 40% of ALL patients had active disease compared to 84% and 95% prior to imatinib. At 24 months, estimated transplant-related mortality was 44% and estimated relapse mortality 24%. Factors associated with shorter overall and progression-free survival were advanced disease at SCT and a female donor/male recipient pairing. No unusual organ toxicities were observed. Compared to historical controls, prior imatinib treatment did not influence overall survival, progression-free survival or non-relapse mortality, while there was a trend towards higher relapse mortality and significantly less chronic graft-versus-host disease.

INTERPRETATION AND CONCLUSIONS

Within the limits of a heterogeneous and relatively small cohort of patients, we found no evidence that imatinib negatively affects major outcomes after SCT, suggesting that imatinib prior to SCT is safe.

Autologous stem cell transplantation for Hodgkin's disease: busulfan, melphalan and thiotepa compared to a radiation-based regimen

We evaluated prognostic factors and treatment outcome of patients with relapsed/refractory Hodgkin's disease (HD) receiving autologous stem cell transplantation (ASCT). In total, 92 patients received total body irradiation, cyclophosphamide and etoposide (TBI/CY/E) (n=42) or busulfan, melphalan and thiotepa (Bu/Mel/T) (n=50) supported with ASCT. A total of 33 (66%) patients receiving the Bu/Mel/T regimen had a prior history of dose-limiting irradiation. Mucositis, hepatic and pulmonary toxicities were the main causes of morbidity and mortality, irrespective of the conditioning regimen. The transplant-related mortality was 15%. With a median follow-up of 6 years (range 2.5-11), the cumulative probabilities of survival, event-free survival (EFS) and relapse at 6 years were 55, 51 and 32%. The 6-year Kaplan-Meier (KM) probabilities of EFS for patients with less advanced disease (patients in first chemotherapy-responsive relapse or second remission (n=42)) and more advanced disease (all other patients (n=50)) were 60 and 44%. No differences in toxicities and efficacy between the conditioning regimens were found. ASCT is an effective treatment for patients with refractory/relapsed HD. Female patients and patients with less advanced disease at transplant had a better outcome. Patients with prior irradiation benefited from the Bu/Mel/T regimen.

Surgical complications of bone marrow transplantation

BACKGROUND

We wished to determine the type of diseases in patients who received bone marrow transplant (BMT) that potentially involve the general surgeon at our institution.

METHODS

The records of 542 patients who underwent bone marrow transplant at Oregon Health and Sciences University between January 1990 and December 2000 were retrospectively reviewed. Gastrointestinal complications included in the study were gastrointestinal bleeding, venoocclusive disease of the liver, intestinal graft versus host disease, pneumatosis intestinalis, necrotizing enteritis, as well as other more common surgical diseases (eg, appendicitis).

RESULTS

Gastrointestinal complications or surgical consultations were noted in 92 of 542 patients (17%). Of these, formal general surgical consultation was obtained in 48 patients (9%). The most common causes for surgical consult were cholecystitis (5), abdominal pain of unknown etiology (5), central line complications (5), small bowel obstruction (4), and appendicitis (4). Twenty-eight (58%) of these patients received an operation. Six patients (13%) died during the same hospitalization as their surgery consult. Forty-four patients with these gastrointestinal symptoms related to transplantation did not receive surgical consult. The mortality in this group was 45%.

CONCLUSIONS

The majority of gastrointestinal complications after bone marrow transplant do not require surgical intervention. However, these conditions may overlap the more common reasons for surgical consult and must be identifiable by the general surgeon. Of patients who did require surgical intervention, it was primarily for common surgical diseases.

A randomized placebo-controlled trial of lisofylline in HLA-identical, sibling-donor, allogeneic bone marrow transplant recipients. The Lisofylline Marrow Transplant Study Group

The purpose of the study was to evaluate the effect of lisofylline (LSF) on engraftment, regimen-related toxicities (RRT), and mortality in patients undergoing allogeneic bone marrow transplantation (BMT). We performed a multicenter, randomized placebo-controlled trial in 60 patients with hematologic malignancies receiving BMT from HLA-identical sibling donors. Patients were randomized to receive either placebo, 2 mg/kg LSF or 3 mg/kg LSF every 6 h, beginning before conditioning and continuing to day 21 or hospital discharge. Treatment groups were balanced with respect to conditioning regimen and disease stage. However, significantly more patients in the 2 mg/kg LSF group were at high risk for RRT due to performance status >/=1, age >/=40 years, and prior exposure to CMV. Nausea and vomiting were the only adverse events observed in a higher proportion of LSF-treated patients that led to study withdrawal in six of 42 patients (14%). The times to neutrophil recovery to >/=500/microl and platelet recovery (>20 000/microl) were not improved by LSF treatment. Nevertheless, no patient who received treatment with 3 mg/kg LSF developed a documented infection between day 0 and 35 or had a serious or fatal infection between day 0 and 100 (P = 0.003 vs placebo for both). The day-100 survival rate was also significantly improved in the 3 mg/kg LSF group (89%), compared with either the 2 mg/kg LSF (48%) or placebo (61%) groups (log-rank test, 3 mg/kg LSF vs placebo, P = 0. 026). We conclude that treatment with LSF 3 mg/kg reduced the incidence of infections and improved 100-day survival in patients receiving related-donor allogeneic bone marrow transplantation. Bone Marrow Transplantation (2000) 25, 283-291.

High dose chemotherapy--results of American studies

The role of high dose chemotherapy in the treatment of solid tumors is a subject of robust debate. Opinions range from the adoption of high dose chemotherapy with hematopoietic progenitor support as standard therapy for a number of solid tumors to the view that the application of such expensive and potentially toxic therapy is always experimental and should be the subject of clinical trials to define the role, if any. In germ cell tumors, the role of high dose chemotherapy is somewhat less contentious. In the US, high dose carboplatin and etoposide-based chemotherapy is routinely accepted as standard therapy for those patients failing prior standard dose regimens. There is increasing acceptance of the role of similar high dose therapy as a component of aggressive second line therapy and some initial acceptance of a potential role in primary treatment of poor risk disease. Formal study of these questions has been hampered by the rarity of the illness, the success of standard therapy and the smaller number of patients presenting with far advanced disease. This review will highlight the scientific underpinning of the role of high dose chemotherapy in multiply relapsed patients, as a component of initial salvage therapy and, finally as an attempt to improve outcome in patients with poor risk presenting features. As well, an attempt will be made to highlight where new prognostic information has influenced the design of current studies.

Outcomes of high-dose chemotherapy and autologous stem-cell transplantation in stage IIIB inflammatory breast cancer

PURPOSE

To evaluate the disease-free survival (DFS) and overall survival (OS), prognostic factors, and treatment-related mortality of women with stage IIIB inflammatory breast cancer (IBC) treated with combined modality therapy (CMT) and high-dose chemotherapy (HDCT) with autologous stem-cell transplantation.

PATIENTS AND METHODS

Between 1989 and 1997, 47 consecutive patients with stage IIIB IBC were treated with CMT and HDCT and were the subject of this retrospective analysis. Chemotherapy was administered to all patients before and/or after definitive surgery. Neoadjuvant and adjuvant chemotherapy was administered to 33 and 34 patients, respectively, and 20 patients received both. All patients received HDCT with autologous stem-cell transplantation, and 41 patients received locoregional radiation therapy. Tamoxifen was prescribed to patients with estrogen receptor (ER)-positive cancer.

RESULTS

The mean duration of follow-up from diagnosis was 30 months (range, 6 to 91 months) and from HDCT was 22 months (range, 0.5 to 82 months). At 30 months, the Kaplan-Meier estimates of DFS and OS from diagnosis were 57.7% and 59.1%, respectively. At 4 years, the Kaplan-Meier estimates of DFS and OS from diagnosis were 51.3% and 51.7%, respectively. In a multivariate analysis, the only factors associated with better survival were favorable response to neoadjuvant chemotherapy (P =.04) and receipt of tamoxifen (P =.06); however, the benefit of tamoxifen was only demonstrated in patients with ER-positive breast cancer. At last follow-up, 28 patients (59. 6%) were alive and disease-free. Seventeen patients (36.2%) developed recurrent breast cancer. Seventeen patients died: 15 from disease recurrence and two (4.2%) from treatment-related mortality due to HDCT.

CONCLUSION

In this analysis, the early results of treatment with CMT and HDCT compare favorably with other series of patients with stage IIIB IBC treated with CMT alone. These outcomes must be confirmed with longer follow-up and controlled studies.

High-dose busulfan, melphalan and thiotepa followed by autologous peripheral blood stem cell (PBSC) rescue in patients with advanced stage III/IV ovarian cancer

The purpose of this study was to evaluate the efficacy of high-dose chemotherapy (HDC) with busulfan, melphalan and thiotepa (BUMELTT) followed by autologous PBSC infusion in treating patients with advanced ovarian cancer. Thirty-one patients, 18 with stage III/IIIc and 13 with stage IV ovarian cancer, were treated with BU (12 mg/kg), MEL (100 mg/m2) and TT (500 mg/m2) and autologous PBSC rescue. Fifteen patients were in clinical complete remission (CR) at treatment; 11 had platinum-sensitive disease. Sixteen patients were not in CR; two had platinum-sensitive disease. The probabilities of overall survival (OS), event-free survival (EFS) and relapse (R) for all patients at 18 months were 0.57, 0.30 and 0.63; for patients in CR, the rates were 0.87, 0.44 and 0.49 and for patients not in CR, 0.38, 0.13 and 0.81. Two patients (6.5%) died of treatment-related causes. Among the 13 patients with platinum-sensitive disease, all are still alive, with seven having relapsed 129-1021 days after PBSC infusion. OS, EFS and R were 1.00, 0.52 and 0.48. Of the 18 patients with platinum-resistant disease, four remain alive (two in remission). Six patients did not respond and eight relapsed from days 104-429. The OS, EFS and R were 0.33, 0.11 and 0.78. We conclude that BUMELTT is well tolerated in patients with advanced ovarian cancer and results are equivalent to other published HDC regimens.

High-dose busulfan, melphalan, and thiotepa followed by autologous peripheral blood stem cell transplantation in patients with aggressive lymphoma or relapsed Hodgkin's disease

The purpose of this study was to evaluate the efficacy of high-dose chemotherapy with busulfan (Bu), melphalan (Mel), and thiotepa (TT), and of autologous peripheral blood stem cell (PBSC) infusion in patients with aggressive non-Hodgkin's lymphoma (NHL) or relapsed Hodgkin's disease (HD). Forty patients, 23 with intermediate (n= 18) or high-grade (n=5) NHL and 17 with HD received Bu (12 mg/kg), Mel (100 mg/kg), TT (450-500 mg/m2) [corrected], and autologous PBSC infusion. Of 27 patients with more advanced disease, 16 had primary refractory disease, 8 were in refractory relapse, and 3 were in third remission. Of 13 patients with less advanced disease, 7 were in untreated or responding first relapse and 3 were in second remission, whereas 3 with high-grade NHL were in first remission. Twenty-nine patients (73%) had received prior radiotherapy (RT) prohibiting a total-body irradiation (TBI)-based conditioning regimen. The projected 2-year probabilities of survival, event-free survival, and relapse for all patients were 0.60, 0.46, and 0.31 (0.85, 0.85, and 0.15 for patients with less advanced disease and 0.48, 0.30, and 0.37 for patients with more advanced disease). The probability of nonrelapse mortality in the first 100 days was 0.17. Severe idiopathic pneumonia syndrome was not observed in any patients with less advanced disease and in only one patient with more advanced disease. A regimen of BuMelTT is well tolerated in patients with aggressive NHL or relapsed HD, and results obtained to date are at least equivalent to other published regimens, including TBI-based regimens. This regimen appears to be a particularly attractive alternative for patients who have already received dose-limiting RT and should be evaluated further in prospective, randomized studies.

Inactivation of the Fanconi anemia group C gene augments interferon-gamma-induced apoptotic responses in hematopoietic cells

Hematopoietic progenitor cells (HPC) from mice nullizygous at the Fanconi anemia (FA) group C locus (FAC -/-) are hypersensitive to the mitotic inhibitory effects of interferon (IFN-gamma). We tested the hypothesis that HPC from the bone marrow of Fanconi group C children are similarly hypersensitive and that the fas pathway is involved in affecting programmed cell death in response to low doses of IFN-gamma. In normal human and murine HPC, IFN-gamma primed the fas pathway and induced both fas and interferon response factor-1 (IRF-1) gene expression. These IFN-gamma-induced apoptotic responses in HPC from the marrow of a child with FA of the C group (FA-C) and in FAC -/- mice occurred at significantly lower IFN doses (by an order of magnitude) than did the apoptotic responses of normal HPC. Treatment of FA-C CD34+ cells with low doses of recombinant IFN-gamma, inhibited growth of colony forming unit granulocyte-macrophage and burst-forming unit erythroid, while treatment with blocking antibodies to fas augmented clonal growth and abrogated the clonal inhibitory effect of IFN-gamma. Transfer of the normal FAC gene into FA-C B-cell lines prevented mitomycin C-induced apoptosis, but did not suppress fas expression or inhibit the primed fas pathway. However, the kinetics of Stat1-phosphate decay in IFN-gamma-treated cells was prolonged in mutant cells and was normalized by transduction of the normal FAC gene. Therefore, the normal FAC protein serves, in part, to modulate IFN-gamma signals. HPC bearing inactivating mutations of FAC fail to normally modulate IFN-gamma signals and, as a result, undergo apoptosis executed through the fas pathway.

High-dose busulfan, melphalan, thiotepa and peripheral blood stem cell infusion for the treatment of metastatic breast cancer

The purpose of this study was to determine the outcome of patients with metastatic breast cancer treated with high-dose busulfan (Bu), melphalan (Mel) and thiotepa (TT) followed by peripheral blood stem cell (PBSC) infusion. Fifty-one patients with chemotherapy refractory (n = 32) or responsive (n = 19) metastatic breast cancer received Bu (12 mg/kg), Mel (100 mg/m2) and TT (500 mg/m2) followed by PBSC collected after chemotherapy and growth factor (n = 43) or growth factor alone (n = 8). The 100 day treatment-related mortality was 8% including one death from cytomegalovirus pneumonia, one from aspiration pneumonia and two from regimen-related toxicity (RRT). Seven of 28 refractory (25%) and 5/7 (71%) responsive patients with evaluable disease achieved a complete response of all measurable disease or all soft tissue disease with at least improvement in bone lesions (PR*). Fifteen of 51 patients (29%) are alive and progression-free a median of 423 days (range 353-934) after treatment, 5/32 (16%) with refractory disease and 10/19 (53%) with responsive disease. The probabilities of progression-free survival (PFS) at 1.5 years for the patients with refractory (n = 32) and responsive (n = 19) disease were 0.24 and 0.53, respectively. These preliminary data suggest that high-dose Bu/Mel/TT has significant activity in patients with advanced breast cancer and may be superior to some previously published regimens.

Phase II study of high-dose busulfan, melphalan and thiotepa with autologous peripheral blood stem cell support in patients with malignant disease

The purpose of this study was to determine the toxicities and potential effectiveness of high-dose busulfan, melphalan and thiotepa (Bu/Mel/TT) followed by autologous peripheral blood stem cell (PBSC) infusion in patients with a variety of diseases. A phase II clinical trial of Bu (12 mg/kg), Mel (100 mg/m2) and TT (500 mg/m2) followed by PBSC infusion in 104 patients with breast cancer (n = 48), malignant lymphoma (n = 25), ovarian cancer (n = 13), multiple myeloma (n = 7) and other malignancies (n = 11) was performed. Sixty-two patients were treated in an academic medical center and 42 in a community cancer center. Grade 3-4 regimen-related toxicities occurred in 14% of patients, causing regimen-related mortality in six (6%) patients with an overall transplant-related mortality of 9%. Transplant-related deaths occurred in 6/62 patients (10%) treated in an academic medical center and in 3/42 (7%) treated in a community cancer center. Complete remissions (CR) were achieved in 1/17 (6%) patients with refractory stage IV breast cancer, 4/4 patients with responsive stage IV breast cancer, 6/13 (46%) with more-advanced lymphoma and 4/4 with less-advanced lymphoma. These patients are alive and disease-free a median of 712, 279, 461 and 404 days after transplant, respectively. Nineteen of 22 patients with stage II-III breast cancer remain alive and disease-free a median of 365 days after transplant. Complete remissions were also seen in 4/9 patients with ovarian cancer and 3/7 with multiple myeloma. The Bu/Mel/TT regimen followed by autologous PBSC infusion is associated with acceptable morbidity and mortality, appears to have significant activity in patients with breast cancer and is well tolerated in the adjuvant setting of stage II-III breast cancer. Bu/Mel/TT also appears to have significant activity in patients with lymphoma, multiple myeloma and possibly ovarian cancer. Further phase II-III studies are warranted in patients with these and other malignancies.

Selective depletion of myelin-reactive T cells with the anti-OX-40 antibody ameliorates autoimmune encephalomyelitis

The OX-40 protein was selectively upregulated on encephalitogenic myelin basic protein (MBP)-specific T cells at the site of inflammation during the onset of experimental autoimmune encephalomyelitis (EAE). An OX-40 immunotoxin was used to target and eliminate MBP-specific T cells within the central nervous system without affecting peripheral T cells. When injected in vivo, the OX-40 immunotoxin bound exclusively to myelin-reactive T cells isolated from the CNS, which resulted in amelioration of EAE. Expression of the human OX-40 antigen was also found in peripheral blood of patients with acute graft-versus-host disease and the synovia of patients with rheumatoid arthritis during active disease. The unique expression of the OX-40 molecule may provide a novel therapeutic strategy for eliminating autoreactive CD4+T cells that does not require prior knowledge of the pathogenic autoantigen.