Risk factors for moderate-to-severe chronic graft-versus-host disease after allogeneic hematopoietic stem cell transplantation.

Among 810 consecutive hematopoietic stem cell transplantation (HSCT) patients, 679 survived more than 3 months and were evaluated for chronic GVHD. The aim of this study was to find predisposing factors increasing the risk of development of moderate-to-severe chronic GVHD. Many of the donors were HLA-identical siblings or related (n = 435), 185 were HLA-matched unrelated, and 59 were mismatched related or unrelated donors. Most of the patients had a hematological malignancy (n = 568), but 111 patients with a nonmalignant disease were included. Two hundred twenty-three patients (33%) developed mild, 41 (6%) moderate, and 15 (2.2%) severe chronic GVHD. The 5-year probability of development of moderate-to-severe chronic GVHD was 10%. We analyzed 30 potential risk factors for chronic GVHD. In the multivariate analysis, acute GVHD) grades II to IV (relative hazard [RH], 2.30; 95% CI, 1.29-4.10; P = .005), CML diagnosis (RH, 2.37; CI, 1.38-4.08; P = .002) and transplantation from an immunized female donor to a male recipient (RH, 2.16; CI, 1.14-4.11; P = .02) were independent risk factors for moderate-to-severe chronic GVHD. Recipient age also was significant (RH, 2.42; CI, 1.23-4.77; P = .01) if CML was not included in the analysis. In patients with no risk factors, the 5-year probability of development of moderate-to-severe chronic GVHD was 5%. In patients with 1 risk factor, the probability was 13%; 2 risk factors, 23%; and 3 risk factors, 45%. Among patients who developed chronic GVHD (n = 279), acute GVHD grades II to IV (RH, 2.18; CI, 1.23-3.86; P < .01) was the only predictive factor for moderate-to-severe chronic GVHD versus mild disease. Patients with previous acute GVHD grades II to IV may benefit from more aggressive initial treatment. This possibility would have to be examined in clinical trials.     

Renal thrombotic microangiopathy associated with chronic graft-versus-host disease after allogeneic hematopoietic stem cell transplantation

Thrombotic microangiopathy (TMA) is a major complication after hematopoietic stem cell transplantation (HSCT). In this study, we examined the clinical and pathologic features of 2 patients and 5 autopsy cases with HSCT-associated renal TMA to clarify the association between graft-versus-host disease (GVHD) and renal TMA. The median interval between HSCT and renal biopsy or autopsy was 7 months (range 3-42 months). Clinically, acute and chronic GVHD occurred in 7 and 4 patients, respectively. Clinical evidence for TMA was detected in 2 patients, while chronic kidney disease developed in all patients. The main histopathological findings were diffuse endothelial injury in glomeruli, peritubular capillaries (PTCs), and small arteries. In addition, all cases showed glomerulitis, renal tubulitis, and peritubular capillaritis with infiltration of CD3+ T cells and TIA-1+ cytotoxic cells, suggesting that GVHD occurred during the development of TMA. Diffuse and patchy C4d deposition was noted in glomerular capillaries and PTCs, respectively, in 2 biopsy and 2 autopsy cases, suggesting the involvement of antibody-mediated renal endothelial injury in more than 50% of renal TMA cases. In conclusion, the kidney is a potential target of chronic GVHD that may induce the development of HSCT-associated TMA. Importantly, some cases are associated with chronic humoral GVHD.     

Oral chronic graft-versus-host disease in pediatric patients after hematopoietic stem cell transplantation.

Chronic graft-versus-host disease (cGVHD) is a serious and potentially life-threatening complication of hematopoietic stem cell transplantation. This study, which is the largest single-center series of oral disease in pediatric patients with cGVHD, describes the oral findings in 49 consecutive patients seen in a pediatric multidisciplinary cGVHD clinic. All consecutive patients seen at the multidisciplinary pediatric hematopoietic stem cell transplantation/cGVHD clinic at the Dana-Farber Cancer Institute (Boston, MA) from July 2001 through October 2003 were included in this study. Subjective and objective assessments of mucosal, salivary gland, and sclerotic pathology were performed for each patient, and specific therapy was initiated when indicated. Oral mucosal cGVHD was identified in 22 (45%) of 49 patients. Only 4 (8%) of 49 patients reported mouth pain, and all patients reported being able to eat well. All patients who required specific therapy for their oral mucosal cGVHD (45%) were already taking at least 1 immunomodulatory agent; however, efficacy of treatment was difficult to assess because of inconsistent follow-up periods. Subjective and objective salivary gland and sclerotic disease were observed far less often. Oral mucosal pathology is common in these patients, and appropriate diagnosis and management of oral lesions is critical to reduce patient morbidity and to improve quality of life. The apparent lack of salivary gland involvement was notable. Developing validated age-appropriate evaluation strategies and identifying effective treatment guidelines will be invaluable in the future management of these patients.     

TLR4 inactivation protects from graft-versus-host disease after allogeneic hematopoietic stem cell transplantation

Graft-versus-host disease (GVHD) is the most common complication after hematopoietic stem cell transplantation. To clarify the role of Toll-like receptor 4 (TLR4), which is a major receptor for bacterial lipopolysaccharides (LPS), in the development of acute GVHD, we used a TLR4-knockout (TLR4^−/−) mouse GVHD model and analyzed the underlying immunological mechanisms. When TLR4^−/− mice were used as bone marrow and splenocyte cell graft donors or recipients, GVHD symptom occurrence and mortality were delayed compared to wild-type (TLR4^+/+) mice. In addition, histopathological analyses revealed that in TLR4^−/−→BALB/c chimeras, liver and small intestine tissue damage was reduced with minimal lymphocytic infiltration. In contrast to TLR4^+/+, TLR4^−/− mice dendritic cells did not express CD80, CD86, CD40, MHC-II or IL-12 during LPS induction and remained in an immature state. Furthermore, the ability of TLR4^−/− mice spleen dendritic cells to promote allogeneic T-cell proliferation and, in particular, T-helper cell 1 (Th1) development was obviously attenuated compared with TLR4^+/+ mice dendritic cells, and the levels of interferon-γ (IFN-γ) and IL-10, Th2-cell specific cytokines, were significantly higher in the serum of TLR4^−/−→BALB/c than in TLR4^+/+→BALB/c chimeric mice. Overall, our data revealed that TLR4 may play a role in the pathogenesis of GVHD and that targeted TLR4 gene therapy might provide a new treatment approach to reduce the risk of GVHD.     

Mucositis after allogeneic hematopoietic stem cell transplantation: a cohort study of methotrexate- and non-methotrexate-containing graft-versus-host disease prophylaxis regimens.

Oral mucositis occurs in up to 75% of recipients of high-dose chemoradiotherapy conditioning regimens used for allogeneic hematopoietic stem cell transplantation (HSCT). As a result of mucositis, narcotic analgesia and total parenteral nutrition (TPN) are commonly required after HSCT. Methotrexate, an antiproliferative graft-versus-host disease (GVHD) prophylaxis agent, impairs mucosal regeneration and worsens and prolongs mucositis. We assessed the effect of substituting sirolimus for methotrexate as GVHD prophylaxis on outcomes associated with mucositis. Two patient cohorts undergoing allogeneic HLA-matched related donor peripheral blood stem cell transplantation with cyclophosphamide/total body irradiation conditioning were prospectively analyzed for mucositis severity and retrospectively reviewed for correlative outcomes. GVHD prophylaxis consisted of sirolimus/tacrolimus (ST) in the study group and tacrolimus/methotrexate (TM) in the control group. Thirty patients received ST and 24 patients received TM as GVHD prophylaxis between October 2000 and May 2003. Mild, moderate, and severe mucositis was noted in 37%, 57%, and 7% of the ST group and 8%, 42%, and 50% of the TM group (P = .0002). Less TPN was used in the ST group than the TM group (17% versus 43% of posttransplantation hospital days; P = .02). The total number of narcotic days was lower in the ST group in comparison with the TM group (median, 13.5 versus 17 days; P = .08). The time to first hospital discharge was shorter in the ST group compared with the TM group (median, 18 versus 22 days; P = .07). The substitution of sirolimus for methotrexate as GVHD prophylaxis is associated with a reduction in mucositis severity. As a result, TPN and narcotic use are reduced, and hospitalization duration is shortened. Less toxic GVHD prophylaxis regimens without methotrexate may have a significant effect on patient quality of life, patient outcomes, and economic outcomes associated with allogeneic stem cell transplantation.     

Iron overload manifesting as apparent exacerbation of hepatic graft-versus-host disease after allogeneic hematopoietic stem cell transplantation.

Iron overload presenting as exacerbation of hepatic graft-versus-host disease (GVHD) after allogeneic hematopoietic stem cell transplantation has not been previously described. We report 6 patients with established hepatic GVHD in whom iron overload (median serum ferritin, 7231 mug/dL; median transferrin saturation, 77%) resulting from a lifetime median of 20 units of packed red blood cell transfusions was manifested by worsening of liver function. Liver biopsies performed in 4 patients confirmed severe iron overload and also hepatic GVHD. Analysis for the C282Y and H63D hemochromatosis gene mutation was negative for the homozygous state in all 6 patients. Erythropoietin-assisted phlebotomy resulted in normalization of liver function at a median of 7 months and of serum ferritin at a median of 11 months. Immunosuppressive therapy was successfully tapered in all 4 patients who completed the phlebotomy program, and this supported the impression that iron overload, rather than GVHD, was the principal cause of liver dysfunction. At a median follow-up of 50 months (range, 18-76 months) from the transplantation and 25 months (range, 5-36 months) from ferritin normalization, all 4 patients require maintenance phlebotomy. We conclude that iron overload can mimic GVHD exacerbation, thus resulting in unnecessary continuation or intensification of immunosuppressive therapy for GVHD, and that maintenance phlebotomy is necessary after successful iron-reduction therapy.     

Autoantibodies in human chronic graft-versus-host disease after hematopoietic cell transplantation

Primary biliary cirrhosis (PBC) and graft-versus-host disease (GVHD) are thought to have common immunopathologic features and previous studies have reported that 5.2 to 81% of patients with chronic GVHD after allogeneic hematopoietic cell transplant have antimitochondrial antibodies (AMA). We studied a total of 89 patients with chronic GVHD and 60 controls for AMA reactivity by ELISA and immunoblotting using recombinant PDC-E2, BCOADC-E2, and OGDC-E2, immunoblotting of beef heart mitochondrial proteins, and reactivity to nuclei, smooth muscle (ASMA), ribonucleoprotein JO-1, extractable nuclear antigen, nuclear proteins SSA/ SSB, ribonucleic P proteinase III, cardiolipin (ACA), liver kidney microsomal, thyroid microsomal, myeloperoxidase, and the reactivity of rheumatoid factor. A subset of 60 chronic GVHD sera were tested for reactivity to gp210 and LBR. Finally, liver tissue from patients with chronic GVHD and PBC was studied by immunohistochemistry to determine whether there was comparable abnormal apical staining of biliary epithelial cells using PDC-E2-specific monoclonal antibodies. Surprisingly, there were no AMA found in the sera from the 89 patients with chronic GVHD. Review of published data on AMA in GVHD suggests that previous results were primarily false positives. In contrast, sera from the patients with GVHD did have a variety of other autoantibodies and, in particular, 20/89 (22.4%) positive ANA, 23/89 (25.8%) positive ASMA, and 9/89 (10.1%) positive ACA. The other autoantibodies assayed were not statistically different from controls. Finally, abnormal biliary epithelial luminal staining of bile ducts was found, as expected, in liver tissue of patients with PBC but was absent in chronic GVHD.     

Chronic kidney disease after myeloablative allogeneic hematopoietic stem cell transplantation.

Because survival of recipients of allogeneic hematopoietic stem cell transplantation (HSCT) has improved, long-term complications become more important. We studied the incidence and risk factors of chronic kidney disease in these patients and evaluated associated posttransplant complications and mortality. We performed a retrospective cohort study of 266 adults who received myeloablative allogeneic HSCT and who survived for >6 months in an 11-year period at a Dutch university medical center. Primary outcome was the incidence of chronic kidney disease defined as a glomerular filtration rate (GFR) of <60 mL/min/1.73 m(2). Chronic kidney disease developed in 61 (23%) of 266 patients, with a cumulative incidence rate of 27% at 10 years. Severe kidney disease (GFR of <30 mL/min/1.73 m(2)) developed in 3% of patients. Only 6 patients developed the thrombotic microangiopathic syndrome SCT nephropathy, and 2 of them needed dialysis. Pretransplant risk factors for chronic kidney disease were lower GFR at day 0 (P < .0001, odds ratio [OR] 0.95 95% confidence interval [CI] 0.93-0.97), female gender, and higher age (P = .001 and P < .0001, respectively). The occurrence of hypertension after transplantation was associated with chronic kidney disease (P < .0001, OR 0.34 95% CI 0.18-0.62). Mortality was 39% after a mean follow-up of 5.1 years. There was no significant difference in survival between patients with and without chronic kidney disease. Chronic kidney disease is a common late complication of myeloablative allogeneic HSCT. Because of the natural decline in renal function with time there is a risk of developing end-stage renal disease in the future. SCT nephropathy seems to be a specific cause of chronic kidney disease that is typically associated with severe kidney disease.     

Identification of gene microarray expression profiles in patients with chronic graft-versus-host disease following allogeneic hematopoietic cell transplantation

Chronic graft-versus-host disease (GVHD) results in significant morbidity and mortality, limiting the benefit of allogeneic hematopoietic cell transplantation (HCT). Peripheral blood gene expression profiling of the donor immune repertoire following HCT may provide associated genes and pathways thereby improving the pathophysiologic understanding of chronic GVHD. We profiled 70 patients and identified candidate genes that provided mechanistic insight in the biologic pathways that underlie chronic GVHD. Our data revealed that the dominant gene signature in patients with chronic GVHD represented compensatory responses that control inflammation and included the interleukin-1 decoy receptor, IL-1 receptor type II, and genes that were profibrotic and associated with the IL-4, IL-6 and IL-10 signaling pathways. In addition, we identified three genes that were important regulators of extracellular matrix. Validation of this discovery phase study will determine if the identified genes have diagnostic, prognostic or therapeutic implications.     

小鼠异基因造血干细胞移植后使用G-CSF对aGVHD的影响

 目的: 探讨小鼠异基因造血干细胞移植(allo-HSCT)后使用粒细胞集落刺激因子(G-CSF)对急性移植物抗宿主病(aGVHD)的影响及其可能的机制。方法: 以雄性C57BL/6小鼠(H-2^b)为异基因供鼠,雄性BALB/c小鼠(H-2^d)为同基因供鼠;以接受8 Gy[⁶⁰Co] γ射线全身照射(TBI)预处理雌性BALB/c小鼠为受鼠,并随机分为7组:单纯TBI组、同基因骨髓+脾细胞移植(Syn-BMST)组、异基因骨髓移植(allo-BMT)组、异基因骨髓+脾细胞移植(allo-BMST)组、Syn-BMST后G-CSF给药(Syn-BMST+G-CSF)组、allo-BMT后G-CSF给药(allo-BMT+G-CSF)组和allo-BMST后G-CSF给药(allo-BMST+G-CSF)组,各G-CSF给药组从移植后第1天(+1 d)开始皮下注射G-CSF 2 μg/d,观察至+60 d。比较各组生存时间、aGVHD发生情况和病理改变,流式细胞术检测骨髓H2-Kb⁺细胞百分率(异基因嵌合率),比较allo-BMST和allo-BMST+G-CSF组+10 d时血清细胞因子(IL-2、IL-4、IFN-γ和TNF-α)水平、脾总有核细胞数(SpTNC)和脾细胞免疫表型的差异。结果: 单纯TBI组小鼠于照射后9~15 d死于造血衰竭,其余各组+10 d时均100%获得造血重建,随机抽取2只异基因骨髓移植受鼠,+30 d供者细胞嵌合率分别为99.8%和99.4%,表明清髓性allo-HSCT模型建立成功。Syn-BMST、Syn-BMST+G-CSF、allo-BMT和allo-BMT+G-CSF组小鼠观察至+60 d均未发生aGVHD。与allo-BMST组相比,allo-BMST+G-CSF组受鼠出现aGVHD时间早、程度重、病理改变严重、存活时间明显缩短(P<0.05)、+10 d SpTNC明显增加(P<0.05)、脾脏NK细胞显著扩增 (P<0.01)、DC1/DC2比值减低(P<0.05),而2组血清IL-2、IL-4、IFN-γ和TNF-α水平差异无统计学意义。结论: 移植后使用G-CSF对小鼠异基因单纯骨髓移植后aGVHD无明显影响,但能显著加重allo-BMST后aGVHD的严重程度并缩短受鼠生存时间,该效应可能与G-CSF诱导供鼠NK细胞扩增有关,提示临床allo-HSCT后早期使用G-CSF可能触发或加重aGVHD的风险。     

Bone density loss after allogeneic hematopoietic stem cell transplantation: a prospective study.

The incidence and course of bone density abnormalities following hematopoietic stem cell transplantation are poorly understood and complicated by the impact of multiple factors. Hip, spine, and wrist bone mineral densities (BMDs) were measured in 104 adults (54 women, 54 men; mean age, 40 years [range, 18-64 years]) at 3 and 12 months after allogeneic transplantation. Clinical and laboratory variables were evaluated using univariate and multivariate analyses to determine risk factors for osteoporosis, fracture, and avascular necrosis. At 3 months posttransplantation, combined (male and female) hip, spine, and wrist z scores were -0.35, -0.42, and +0.04 standard deviations, respectively. At 12 months both men and women experienced significant loss of hip BMD (4.2%, P < .0001); changes in the spine and wrist were minimal. The cumulative dose and number of days of glucocorticoid therapy and the number of days of cyclosporine or tacrolimus therapy showed significant associations with loss of BMD; age, total body irradiation, diagnosis, and donor type did not. Nontraumatic fractures occurred in 10.6% of patients and avascular necrosis in 9.6% within 3 years posttransplantation. The decrease in height between pretransplantation and 12 months posttransplantation was significant (P = .0001). Results indicate that loss of BMD after allogeneic stem cell transplantation is common and accelerated by the length of immunosuppressive therapy and cumulative dose of glucocorticoid. An increased incidence of fracture and avascular necrosis may adversely impact long-term quality of life. Prevention of bone demineralization appears warranted after stem cell transplantation.     

Increasingly frequent diagnosis of acute gastrointestinal graft-versus-host disease after allogeneic hematopoietic cell transplantation.

The reported incidence of grades II to IV acute graft-versus-host disease (GVHD) after hematopoietic cell transplantation with HLA-identical sibling donors has increased considerably during the past 15 to 20 years at our center. The purpose of this study was to evaluate the potential reasons for this change. We reviewed organ stages and overall grades of GVHD for 2220 patients who received a first marrow or peripheral blood cell transplant from an HLA-identical sibling or an HLA-allele-matched unrelated donor with the use of a posttransplantation immunosuppressive regimen that included both methotrexate and cyclosporine between 1985 and 2001. The most striking change was an increased incidence of stage 1 gut involvement from 10% to 20% before 1992 to 50% to 60% since 1992, both with related and unrelated donors. This change increased the incidence of grade II GVHD with sibling donors, such that the overall incidence of grade II to IV GVHD is now 60% to 70%. Among patients with chronic myeloid leukemia in chronic phase, the increasingly frequent diagnosis of acute GVHD since 1992 has not been associated with decreased survival. A high diagnostic sensitivity and increased awareness that gut GVHD can occur without skin involvement account for the increased incidence of acute GVHD at our center.     

Interleukin 12 is associated with reduced relapse without increased incidence of graft-versus-host disease after allogeneic hematopoietic stem cell transplantation.

Interleukin (IL)-12 has antitumor effects in murine studies. To evaluate this clinically, we investigated whether high levels of circulating IL-12 in patients after allogeneic hematopoietic stem cell transplantation (HSCT) are associated with improved relapse-free survival. We prospectively studied 134 patients undergoing HSCT. Median follow-up was 1158 days (range, 70-1792 days). Plasma IL-12 levels were measured before transplantation and on days 0, +4, +7, and +14 after transplantation. The highest levels were seen on days +4 and +7 and were categorized by a cluster analysis of the logarithmically transformed IL-12 concentrations, which were then correlated with relapse-free survival. Forty-six patients had low levels of IL-12 (median, 2 pg/mL; range, 0-6.5 pg/mL), 49 patients had medium levels (median, 20.5 pg/mL; range, 7-75.5 pg/mL), and 25 patients had high levels (median, 181 pg/mL; range, 84-623 pg/mL). Patients with high IL-12 levels before transplantation had the highest increase after transplantation. With a multivariate Cox model for relapse onset, with the low IL-12 level as the reference, patients in the high-IL-12 group had an adjusted hazard ratio of 0.27 (95% confidence interval, 0.09-0.79), and medium group patients had a hazard ratio of 0.65 (95% confidence interval, 0.31-1.36). The incidences of relapse at 500 days by Kaplan-Meier analysis by IL-12 group were 23.0% (high group), 40.3% (medium group), and 48.8% (low group). There was no association between IL-12 levels and the risk of acute graft-versus-host disease (GVHD; P = .51) or chronic GVHD (P = .28). In conclusion, high IL-12 levels after HSCT are associated with improved relapse-free survival without increasing the risk for GVHD. Patients with high pretransplantation IL-12 levels have an increased likelihood of higher posttransplantation IL-12 levels, possibly because of a host-graft interaction, and this may predispose to better clinical outcomes.     

骨髓间质干细胞降低大鼠移植物抗宿主反应的实验研究

目的 探讨MSCs对GVHD的作用及其机制.方法 建立大鼠同种异体骨髓移植模型,同时输入供者的T淋巴细胞诱导出移植物抗宿主反应,联合或不联合移植供体来源的MSCs,观察受鼠的生存时间,同时利用RT-PCR法研究Th1/Th2淋巴细胞亚群的比例,用ELISA法检测移植后体内IL-4细胞因子的浓度.结果 GVHD组的平均生存时间为(17.30±2.33)天,实验组的平均生存时间为(24.10±2.36)天 , 与单独移植HSCs相比,MSCs与HSCs共移植明显延长的受鼠的生存时间.同时,GVHD组Th1/Th 2 细胞比值为1.29±0.06,IL-4因子的浓度平均为(14.84±2.59) pg/mL,实验组Th1/Th 2细胞比值为(0.77±0.14),IL-4因子的浓度平均为(40.09±13.99) pg/mL.MSCs与 HSCs 共移植降低了体内Th1/Th2淋巴细胞亚群的比例,提高了体内IL-4细胞因子的浓度.结论 MSCs与HSCs共移植能有效抑制HSCs移植后致死性GVHD的发生,延长生存时间,同时MSCs 可能通过作用于体内Th1/Th2淋巴细胞亚群的比例,促进体内IL-4细胞因子的分泌从而间接发挥了抑制GVHD的作用.     

Bone marrow-derived mesenchymal stem cells decrease acute graft-versus-host disease after allogeneic hematopoietic stem cells transplantation

Graft-versus-host disease is a major complication of allogeneic hematopoietic stem cells transplantation, leading to serious morbidity and mortality. Mesenchymal stem cells(MSC)from bone marrow cause immunoregulation in vitro and in vivo. They also have the potential to protect from lethal GVHD after both autologous and allogeneic Hematopoietic Stem Cells Transplantation (HSCT). In this study, we investigated the mechanisms responsible for GVHD in the allo-HSCT co-transplantation with MSC condition. The model of acute GVHD in Rats was established using allogeneic HSC with donor-derived T cells transplantation, with or without additional donor-derived MSC co-transplantation. The degrees of GVHD were compared, the differentiation of CD4⁺, CD8⁺, Th1/Th2 and CD4⁺CD25⁺ T cells in vivo were assessed by flow cytometry and RT-PCR analyses. We found that MSC inhibited lethal GVHD after allo-HSCT. The value of CD8⁺ and CD4⁺ T cells and the ratio of Th1/Th2 T cell subsets decreased, at the same time the proportion of CD4⁺CD25⁺ T cells increased both in spleen lymphocytes and thymocytes in vivo after allo-HSCT with MSC co-transplantation compared with conventional allo-HSCT. Our results strongly suggested that BM-derived MSC has the function of preventing lethal GVHD after allo-HSCT by means of homeostasis of T subsets in vivo.     

Acute and chronic graft-versus-host disease after ablative and nonmyeloablative conditioning for allogeneic hematopoietic transplantation.

In this study, we evaluated the influence of nonmyeloablative and ablative conditioning regimens on the occurrence of acute and chronic graft-versus-host disease (GVHD). One hundred thirty-seven patients undergoing matched-related sibling transplantations received the same GVHD prophylaxis. Myeloablative regimens included intravenous busulfan/cyclophosphamide (n=45) and fludarabine/melphalan (n=29). Patients in the nonmyeloablative group (n=63) received fludarabine/idarubicin/cytarabine, cisplatin/fludarabine/idarubicin, and fludarabine/cyclophosphamide. The actuarial rate of grade II to IV acute GVHD was significantly higher (hazard ratio, 3.6; 95% confidence interval, 1.5-8.8) in patients receiving ablative regimens (36%) compared with the nonmyeloablative group (12%). The cumulative incidence of chronic GVHD was higher in the ablative group (40%) compared with the nonmyeloablative group (14%). The rates were comparable within the first 200 days and were significantly higher in the ablative group beyond day 200 (hazard ratio, 5.2; 95% confidence interval, 1.2-23.2). Nonrelapse and GVHD-related mortality were relatively low in both groups. The use of the described nonmyeloablative preparative regimens was associated with a reduced incidence of grade II to IV acute GVHD and chronic GVHD compared with the busulfan/cyclophosphamide and fludarabine/melphalan transplant regimens. It is interesting to note that nonrelapse mortality with nonmyeloablative regimens in older and more debilitated patients was low (14%) and comparable to that achieved with standard high-dose regimens in younger patients.     

CD40L表达在异基因造血干细胞移植中GVHD发生的意义

目的：初步探讨在异基因造血干细胞移植（HSCT）中发生移植物抗宿主病（GVHD）患者DC40L表达的变化以及意义。方法：HSCT治疗重型β-地中海贫血（n=12）和遗传性溶血性贫血（n=1）成功植入的儿童患者，其中脐血移植（UCBT）8例，异基因外周血造血干细胞移植(allo-PBSCT)5例，在移植前、移植后发生GVHD时采用流式细胞仪检测和比较外周血中CD40L和CD40的表达。结果：3例UCBT无GVHD，其余均发生了Ⅰ-Ⅳ度急性GVHD。急性GVHD发生时CD4^ CD40L^ 和CD8^ CD40LT细胞表达明显升高，allo-PBSCT者更明显；慢性GVHD发生时患者的CD40L^ 、CD25^ 和CD69^ 在CD4^ 和CD8^ T细胞上的表达亦增加。CD19^ CD40^ B细胞的表达在UCBT和allo-PBSCT的3个月内则一直处于低于正常的水平。结论：CD40L高表达与GVHD的发生相关，提示CD40-CD40L共刺激途径在GVHD的发生中可能起着重要作用。     

Sirolimus and thrombotic microangiopathy after allogeneic hematopoietic stem cell transplantation.

Thrombotic microangiopathy (TMA) may occur after allogeneic hematopoietic stem cell transplantation (HSCT) and is related in part to calcineurin inhibitor toxicity. We observed a higher-than-expected rate of TMA when calcineurin inhibitors were combined with sirolimus. To determine the incidence of and risk factors for TMA after HSCT, we performed a retrospective cohort analysis of myeloablative allogeneic HSCT recipients between 1997 and 2003. TMA diagnosis required the simultaneous occurrence of (1) creatinine increase >2 mg/dL or >50% above baseline, (2) schistocytosis, (3) increased lactate dehydrogenase, and (4) no evidence of disseminated intravascular coagulopathy. A total of 111 sirolimus-exposed subjects were compared with 216 nonexposed subjects after HSCT. TMA occurred in 10.8% of the sirolimus group and 4.2% in the nonsirolimus group (odds ratio, 2.79; P=.03). Sirolimus exposure was associated with TMA earlier than in nonsirolimus patients (25 versus 58 days; P=.04). Only the use of sirolimus (exact odds ratio, 3.49; P=.02) and grade II to IV acute graft-versus-host disease (exact odds ratio, 6.60; P=.0002) were associated with TMA in regression analyses. Treatment of TMA varied among affected individuals. Renal recovery was complete in 92% of sirolimus-treated patients. Overall survival after TMA diagnosis was better for sirolimus subjects than for nonsirolimus subjects (58.3% versus 11.1%; P=.02). Sirolimus seems to potentiate the effects of calcineurin inhibitors on TMA after HSCT. TMA associated with sirolimus seems reversible and has a favorable prognosis when compared with TMA associated with calcineurin inhibitors alone. A careful monitoring strategy for TMA should be used with a sirolimus-containing graft-versus-host disease prophylaxis regimen.     

Preemptive cellular immunotherapy after T-cell-depleted allogeneic hematopoietic stem cell transplantation.

GVHD is a life-threatening complication of allogeneic hematopoietic stem cell transplantation (HSCT). GVHD is due to donor lymphocytes that are cotransplanted with donor stem cells. These donor lymphocytes are primed by histocompatibility differences between donors and recipients and activated by a cytokine storm caused by the conditioning regimen. The most efficient method for prevention of GVHD consists of T-cell depletion (TCD) of the graft. However, TCD usually leads to an increased risk of leukemia relapse because of the loss of the graft-versus-leukemia (GVL) effect. Several groups have studied the feasibility of preemptive donor lymphocyte infusion (DLI) to lessen the impact of TCD on leukemia relapse. Preemptive DLI is given several weeks to months after the transplantation, ie, after the cytokine storm and after the patient has recovered from conditioning-regimen-related toxicities. After briefly discussing various techniques of TCD of the graft and the efficacy of DLI, this article reviews the first clinical studies evaluating a strategy of TCD of the graft followed by preemptive DLI.     

Voriconazole and sirolimus coadministration after allogeneic hematopoietic stem cell transplantation.

Sirolimus is increasingly used in transplantation for prevention and treatment of graft-versus-host disease and organ rejection. Voriconazole is contraindicated when used concomitantly with sirolimus because of a substantial increase in sirolimus drug exposure with unadjusted dosing, but voriconazole is also considered the best initial treatment of invasive aspergillosis and other fungal infections. Patients who received voriconazole and sirolimus concomitantly were identified by a review of the medical records of all allogeneic hematopoietic stem cell recipients at our institution from September 1, 2002, to June 1, 2005. Data including baseline characteristics, indications for both drugs, and potential adverse effects were evaluated. Eleven patients received voriconazole and sirolimus concomitantly for a median of 33 days (range, 3-100 days). In 8 patients whose sirolimus dose was initially reduced by 90%, trough sirolimus levels were similar to those obtained before the administration of voriconazole; no obvious significant toxicity from either drug was observed during coadministration. Serious adverse events were observed in 2 patients in whom sirolimus dosing was not adjusted during voriconazole administration. Sirolimus and voriconazole may be safely coadministered if there is an empiric initial 90% sirolimus dose reduction combined with systematic monitoring of trough levels.