Evaluation of cytomegalovirus-specific T-cell reconstitution in patients after various allogeneic haematopoietic stem cell transplantation using interferon-gamma-enzyme-linked immunospot and human leucocyte antigen tetramer assays with an immunodominant T-cell epitope

Cytomegalovirus (CMV) infection is a major complication for patients who received allogeneic haematopoietic stem cell transplantation (HSCT). Accurate monitoring of CMV-specific T-cell reconstitution is required for appropriate decision on treatment, such as anti-viral drugs, which have adverse effects. Although human leucocyte antigen (HLA) tetramer and interferon-gamma-enzyme-linked immunospot (IFN-gamma-ELISPOT) assays have been used to measure CMV-specific T cells, detailed comparison of these assays and kinetics of anti-CMV T-cell reconstitution between reduced-intensity transplantation (RIST) and conventional HSCT has not yet been performed. In this study, we performed prospective comparative monitoring of CMV-specific T cells using HLA tetramer and IFN-gamma-ELISPOT assays with a single immunodominant CMV(495) peptide in 28 HLA-A*0201 and 9 HLA-A*0206 patients after various allogeneic HSCTs. The IFN-gamma-ELISPOT assay was more sensitive for evaluation of functional T cells than the HLA tetramer assay, and CMV-specific T cells were reconstituted earlier in patients who received RIST without anti-thymocyte globulin (ATG) than those receiving RIST with ATG or conventional HSCT. The threshold level for protection from CMV reactivation was estimated as over 1 x 10(6) cells/l peripheral blood with the IFN-gamma-ELISPOT assay. These results demonstrate that the IFN-gamma-ELISPOT assay with CMV(495) provides more accurate evaluation on CMV immunity in HLA-A*0201 and -A*0206 patients, and may be useful for determining timing of various treatments.     

Evaluation of the NucliSens CMV pp67 assay for detection and monitoring of human cytomegalovirus infection after allogeneic stem cell transplantation

Preemptive treatment based on the sensitive detection of CMV-DNA has helped to reduce HCMV-related mortality after allogeneic stem cell transplantation (SCT). Detection of active viral replication might help to better predict HCMV disease. In this study, 33 recipients at risk for HCMV infection after allogeneic SCT were prospectively monitored 1x/week for active HCMV infection by NASBA, whole blood DNA-PCR and virus culture assays. Preemptive antiviral therapy was initiated after the second positive PCR result, while NASBA results were not considered for clinical decision-making. Overall, a high agreement between PCR and NASBA on a per sample (85.3%) and per patient (87.9%) level was demonstrated. HCMV DNA titers in the blood were found to be higher in PCR(+)/NASBA(+) compared to PCR(+)/NASBA(-) samples (P < 0.01). None of the NASBA-negative patients developed HCMV disease. Sixteen of 18 patients receiving PCR-based preemptive therapy were also found NASBA positive. There was no difference between the assays for the time to the first positive test result. However, the time to the first negative test result upon initiation of antiviral therapy was significantly shorter for the NASBA assay (P = 0.002), indicating a high positive predictive value to assess the efficacy of antiviral therapy. Three patients developed late-onset HCMV disease, all of whom were found to be PCR and NASBA positive. In conclusion, the data presented clearly demonstrate the value of patient monitoring using the NASBA assay to early diagnose active HCMV infection and to assess the efficacy of antiviral therapy in high risk patients after allogeneic SCT. A prospective comparison of PCR-based vs NASBA-based preemptive therapy is ongoing.     

Detection of cytomegalovirus proteins by flow cytometry in the blood of patients undergoing hematopoietic stem cell transplantation

Cytomegalovirus (CMV) infection and associated diseases continue to be a major complication encountered by patients undergoing high-dose chemoradiotherapy and hematopoietic stem cell transplantation (HSCT). A number of studies revealed that identification of CMV in the blood of HSCT patients was a predictor of future CMV disease. The purpose of this study was to determine if CMV proteins detected by flow cytometry could be a rapid and more quantitative way to monitor CMV infections and CMV antigenemia in HSCT patients. Preliminary studies showed that CMV immediate early (IE), early (E), and late (L) tegument proteins were specifically identified in CMV-infected cell lines and not in uninfected cells. We evaluated CMV antigen detection by flow cytometry in blood samples collected before and after transplantation in 56 serially collected blood samples from 17 HSCT patients and CMV protein expression was compared to CMV isolation. CMV IE and E proteins were not detected in any of the samples analyzed. However, CMV L protein detection by flow cytometry correlated with virus isolation in serially collected blood samples. Samples from 14 patients were evaluated by both techniques, at the same time intervals. There was a 100% correlation (8/8) between the lack of CMV antigen detection by flow cytometry and the failure to isolate infectious virus. Moreover, 5 of 6 patients who were positive for CMV L antigen by flow cytometry also were positive by virus isolation techniques. When flow cytometry and virus isolation did not detect CMV antigen on the same day, CMV positivity was first detected by flow cytometry. Then, 1-2 weeks later, positive virus isolation was documented. This study indicates that flow cytometric identification of CMV antigenemia correlates with isolation of CMV in HSCT patients and may be a predictive test for the rapid detection of CMV in the blood.     

Ganciclovir预防异基因造血干细胞移植后巨细胞病毒感染

目的 :评价Ganciclovir在异基因造血干细胞移植 (allo HSCT)后预防巨细胞病毒 (CMV)感染的效果。方法 :观察allo HSCT患者 46例 ,全部病例均系移植前受者和 (或 )供者的CMV IgG阳性 ,分为预防组 2 4例 ,对照组 2 2例。allo HSCT后当患者血中性粒细胞 >1.0× 10 9/L时 ,预防组开始用GCV 10mg·kg-1·d-1,分两次静滴 ,连续 5d ;然后改为 5mg·kg-1·d-1,每周用 5d ,直至 +10 0d。对照组未预防性使用GCV。结果 :在 +10 0d内 ,预防组和对照组的CMV感染率分别为 8% (2 / 2 4)、32 % (7/ 2 2 ) ,P <0 .0 5 ;CMV病发病率分别为 0 %、18% (4 / 2 2 ) ,P <0 .0 5。两组患者在 +10 0d和 +180d内的死亡率分别为 4% (1/ 2 4)和 5 % (1/ 2 2 ) ,P >0 .0 5 ;12 .5 % (3/ 2 4)和 9% (2 / 2 2 ) ,P >0 .0 5。预防组的死因分别为并发细菌和真菌感染、CMV间质性肺炎或原发病复发 ;对照组的死因均是CMV间质性肺炎。结论 :allo HSCT后预防性使用GCV能明显抑制CMV感染 ,减少CMV病发病率。GCV的主要毒副作用是导致中性粒细胞减少 ,使患者继发感染甚至死亡的机率增加。GCV预防性使用的最佳剂量、用药方案及持续时间均有待进一步探讨     

Endoscopic diagnosis of cytomegalovirus gastritis after allogeneic hematopoietic stem cell transplantation

AIM:To clarify the endoscopic and clinical findings of cytomegalovirus(CMV) gastritis after allogeneic hematopoietic stem cell transplantation(allo-SCT).METHODS:Between 1999 and 2005,523 patients underwent allo-SCT at our hospital,and 115 of these patients with gastrointestinal symptoms underwent esophagogastroduodenoscopy.RESULTS:CMV gastritis was diagnosed pathologically in seven patients(1.3%) with the other 108 patients serving as controls.Six of the seven patients developed positive CMV antigenemia,and...     

Drug-resistant human cytomegalovirus infection in children after allogeneic stem cell transplantation may have different clinical outcomes

Three seropositive pediatric recipients of allogeneic stem cell transplantation out of a group of 42 patients receiving T-cell-depleted, unrelated transplants and 37 patients receiving T-cell-depleted, haploidentical transplants were monitored longitudinally for human cytomegalovirus (HCMV) infection and the emergence of antiviral drug resistance. Early in the posttransplant course, all 3 patients developed HCMV mutations conferring drug resistance to ganciclovir. One child additionally developed multidrug resistance to foscarnet and cidofovir, with mutations in the viral phosphotransferase gene (UL97) and the DNA-polymerase gene (UL54) being found. These data show that resistant HCMV infection does not necessarily correlate with a severe clinical outcome. The early detection of genotypic resistance up to 129 days before the emergence of phenotypic resistance and the dissociation of resistance patterns among different body sites emphasize the importance of genotypic analyses of different DNA specimens for an efficient antiviral therapy. T-cell-depleted children having transplantation might be at an increased risk for the development of drug resistance.     

Prognostic impact of minimal residual disease analysis by flow cytometry in patients with acute myeloid leukemia before and after allogeneic hemopoietic stem cell transplantation

Allogeneic stem cell transplantation (allo‐SCT) has become the treatment of choice in patients with intermediate‐risk and high‐risk acute myeloid leukemia (AML). The quality of response to treatment, assessed in terms of detection of minimal residual disease (MRD), has been consistently associated with prognosis and clinical outcome in patients with AML. The aim of the present study was to evaluate the prognostic impact of analyzing MRD in bone marrow using 4‐color multiparametric flow cytometry (MFC) in 29 patients with AML before and after allo‐SCT. Eighteen patients who were shown to be MRD‐negative [≤0.1% leukemia‐associated immunophenotypes (LAIPs)] by MFC at transplantation and underwent allo‐SCT had lower rates of relapse (15% vs. 66%, P = 0.045), better overall 1‐yr survival (83% vs. 52%, P = 0.021) and a lower cumulative incidence of relapse (P = 0.032) than patients who were MRD‐positive (>0.1%). All post‐transplant MRD‐positive patients underwent a therapeutic intervention after transplant (tapering of immunosuppression, donor lymphocyte infusion, or re‐transplant) with the intention of preventing relapse. Disease was controlled and MRD disappeared in five of these patients. Disease recurred in the other seven patients. We can conclude that follow‐up with MFC for the detection of MRD in AML before and after SCT is useful for predicting relapse. In the post‐transplant setting, monitoring of MRD by MFC could be a key preemptive intervention.     

Evaluation of the COBAS Amplicor HCMV Monitor for early detection and monitoring of human cytomegalovirus infection after allogeneic stem cell transplantation

Early diagnosis of human cytomegalovirus (HCMV) infection and the introduction of preemptive antiviral therapy have reduced HCMV-related mortality after allogeneic stem cell transplantation. A critical goal remains stratifying risk profiles and minimizing potential harm owing to antiviral overtreatment. We compared the commercially available standardized COBAS Amplicor CMV Monitor (CACM) to an in-house PCR assay, for the monitoring of HCMV infection. Seventy-two patients were surveyed by an in-house PCR of whole blood, quantitative viral load assessment by CACM and virus culture assays in a prospective and a retrospective study. A high concordance between CACM and PCR was documented. The viral load at onset correlated with the peak viral load (Spearman rank correlation R=0.634, P=0.0004). In patients developing HCMV disease, both viral loads were in trend higher (P=0.823, respectively P=0.053), and the viremic episodes longer (P=0.015), as compared to asymptomatically HCMV-infected patients. The serological pre-transplant status was the major risk factor for the development of HCMV disease, showing highest risk for seropositive patients receiving a seronegative graft, whereas donor type (related or unrelated) and graft type (bone marrow or peripheral blood mobilized stem cells) did not have an influence. HCMV infection proved to be a risk factor for the development of non-viral opportunistic infections (P=0.002).     

巨细胞病毒特异性细胞毒性T淋巴细胞治疗造血干细胞移植后难治复发性巨细胞病毒感染的临床分析

目的 探讨体外扩增的巨细胞病毒(CMV)特异性细胞毒性T淋巴细胞(CMV-CTL)在难治复发性巨细胞病毒感染患者中的疗效及安全性.方法 给予28例难治复发性CMV感染患者输注CMV-CTL,其中19例患者CMV-CTL来自造血干细胞移植原供者,9例来自第三方供者.第1疗程输注1～2次,观察疗效和副作用;第1疗程完全缓解(CR)后复发的患者给予第2疗程治疗,输注1～2次.结果 21例CMV血症患者和7例CMV病患者接受CMV-CTL治疗,首次输注CTL中位治疗时间为移植后76(39 ～321)d,CTL输注中位细胞数为1.0(0.5～10.0)×10 7.第1疗程后,21例CMV血症患者和4例CMV病患者获得CR,CMV血症CR率为100％,CMV病CR率为4/7;获得CR的中位时间分别为首次CTL输注后9(3～23)d和7(4～18)d.6例CMV血症患者和1例CMV病患者CR后复发而给予第2疗程治疗,其中4例CMV血症患者和1例CMV病患者获得CR.5例次患者输注后出现移植物抗宿主病,均为轻中度皮肤受累.随访中6例死于CMV感染,2例死于其他移植后并发症.结论 初步结果显示,体外扩增的CMV-CTL输注治疗难治复发性CMV感染安全有效,但输注方案有待进一步完善.     

Reconstitution of the Epstein-Barr virus-specific cytotoxic T-lymphocyte response following T-cell-depleted myeloablative and nonmyeloablative allogeneic stem cell transplantation

The recovery of circulating antigen-specific T-cell immunity to Epstein-Barr virus (EBV) was determined in ELIspot assays following allogeneic myeloablative or nonmyeloablative stem cell transplantation (MST/NST). In 8 of 12 MST patients receiving an alemtuzumab-treated graft, the frequency of the EBV-specific reactivities was similar to or greater than that seen in the healthy controls. A response was detectable in 3 of 6 and 6 of 9 patients by 3 and 6 months, respectively, and in all patients by one year following MST. In contrast, only 1 of 9 (95% confidence interval [CI], 0-2.8) patients made a detectable EBV-specific response by 6 months following NST conditioned with fludarabine, melphalan, and alemtuzumab. Responses were detected in 7 of 10 patients by 1 year after NST. Parallel surveillance demonstrated that other virus infections occurred more frequently and earlier after transplantation in NST patients. The use of alemtuzumab in vivo in the nonmyeloablative conditioning might have resulted in the delay in EBV-specific T-cell recovery and increased virus infections.     

Monitoring MRD with flow cytometry: an effective method to predict relapse for ALL patients after allogeneic hematopoietic stem cell transplantation

This study evaluated the prognostic value of minimal residual disease (MRD) monitoring by four-color flow cytometry (FCM) in patients with acute lymphoblastic leukemia (ALL) undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT). MRD was examined with four-color FCM at different time points in 139 patients (including pediatric and adult patients) with ALL after allo-HSCT. Real-time quantitative polymerase chain reaction (RQ-PCR) was applied to evaluate the MRD of Philadelphia chromosome-positive ALL (Ph+ ALL) patients. Patients who were FCM-positive (FCM+) after transplantation had a lower event-free survival (EFS) of 0.54 and a higher cumulative incidence of relapse (CIR) of 0.54 compared to an EFS of 0.80 and a CIR of 0.08 in FCM-negative (FCM−) patients (EFS, p < 0.001; CIR, p < 0.001). Similar results were obtained in high-risk patients and Ph+ ALL patients. Moreover, a FCM+ status after the second month post-HSCT (defined as MRD positive) proved to be a predictor of leukemia relapse. Multivariate analysis for EFS, OS and CIR showed that MRD status after transplantation was an independent prognostic factor (p < 0.001, p = 0.013, and p < 0.001, respectively). A good correlation was found between the MRD results of FCM and RQ-PCR (n = 126 pairs, Spearman r = 0.8139, p < 0.001). MRD monitoring by four-color FCM post-transplantation is an important tool for relapse prediction in ALL patients. Prompt and appropriate pre-emptive anti-leukemia treatment could be considered based on the status of MRD after HSCT.     

Clinical implication of minimal residue disease monitoring by WT1 gene detection and flow cytometry in myelodysplastic syndrome with allogeneic stem cell transplantation

<正>Objective To investigate the clinical significance ofminimal residual disease (MRD) monitoring by using WT1 gene and flow cytometry (FCM) in patients with myelodysplastic syndrome (MDS) receiving allogeneic stem cell transplantation (allo-HSCT). Methods WT1gene and MDS-related abnormal immunophenotype were examined by real-time quantitative polymerase chain reaction (RQ-PCR) and FCM,respectively. The bone     

应用血浆荧光定量聚合酶链反应诊断异基因造血干细胞移植受者巨细胞病毒感染

目的：探讨血浆荧光定量聚合酶链反应(Q—PCR)法对人巨细胞病毒(HCMV)活动性感染的诊断价值及对临床用药的指导意义。方法：收集15例患者共204份标本，应用荧光Q-PCR方法对其干细胞移植术后外周血浆HCMV-DNA进行动态监测。结果：血浆Q-PCR共检出8例患者共48份(23．52％)标本阳性；治疗有效者Q-PCR提示DNA拷贝迅速转阴，治疗耐药者Q-PCR提示DNA拷贝在停药后短期转阳或不转阴。结论：血浆Q-PCR是一种新的敏感、特异、快速的诊断方法，其HCMV-DNA的量化有助于早期诊断治疗，另对HCMV活化状态评估及药物疗效监测、减少药物滥用方面有重要的指导作用。     

Abortive human cytomegalovirus infection in patients after allogeneic bone marrow transplantation.

Infection with human cytomegalovirus (HCMV) after allogeneic bone marrow transplantation (BMT) was studied in 12 HCMV seronegative recipients of marrow from seropositive donors by weekly monitoring of cultures, expression of HCMV antigenemia (pp65) in granulocytes, polymerase chain reaction (PCR) on HCMV-DNA in granulocytes and IgM and IgG anti-HCMV antibodies. Eight patients remained negative in all tests as did 33 HCMV seronegative recipients of marrow from seronegative donors. In four patients, a transient expression of HCMV antigen pp65 in granulocytes from peripheral blood, together with a positive PCR on HCMV-DNA from the same samples were found without positive cultures, seroconversion or expression of other HCMV antigens in granulocytes. The data indicate the presence of an abortive HCMV infection in these four patients.     

更昔洛韦胶囊在造血干细胞移植患者巨细胞病毒血症中的应用

目的 探讨更昔洛韦(ganciclovir,DHPG)胶囊治疗造血干细胞移植(HSCT)后患者巨细胞病毒(CMV)血症的疗效和安全性.方法 选择2006年2月至5月在北京大学血液病研究所行HSCT的30例移植后CMV血症患者进行前瞻性研究.CMV感染预防采用更昔洛韦10 mg/(kg·d),分2次静脉滴注,移植前第9天至移植前第2天,连续8 d.移植后应用定量多聚酶链反应(PCR)定期进行病毒DNA检测,CMV-DNA定量＞6.0×102拷贝/mL或＜1×105拷贝/mL的患者应用更昔洛韦胶囊1 g每日3次治疗.结果 HSCT后发生CMV血症的中位时间为移植后42 d,诊断时CMV-DNA中位数4.626×103拷贝/mL.更昔洛韦胶囊治疗的总有效率为90%,14 d转阴率66.67%,转阴中位时间10 d.4例(13.3%)出现不良事件,程度为轻至中度,表现为血细胞计数减少3例,转氨酶升高1例.结论 更昔洛韦胶囊用于治疗HSCT后CMV血症患者安全有效.     

The immunosuppressive effect of human cytomegalovirus infection in recipients of allogeneic hematopoietic stem cell transplantation

In immune-competent individuals, human cytomegalovirus (HCMV) infection is associated with impairment of T-cell function. Our goal was to evaluate prospectively whether clinically asymptomatic HCMV infection in allogeneic hematopoietic stem cell transplantation (alloHSCT) recipients, treated pre emptively with ganciclovir, influences T-cell function as well. Mitogen-stimulated T-cell proliferative activity, together with cell surface markers, was tested in 49 patients on days + 30, + 45, + 60, and + 90 after alloHSCT and, additionally, in cases of positive HCMV pp65-antigenemia. HCMV infection was diagnosed in 19 patients. None of them developed HCMV disease. T-cell proliferative activity was significantly decreased on days when HCMV antigenemia was positive as compared to days without antigenemia. The number of pp65-positive cells negatively correlated with proliferative response. Comparison of patients who did experience HCMV infection with those who did not reveals significant decrease of T-cell proliferative activity observed on days + 30 and + 45, a time period when antigenemia was most frequently found to be positive, whereas no difference was detected on days + 60 and + 90. We conclude that, even clinically asymptomatic, HCMV infection has negative impact on T-cell proliferation capacity in alloHSCT recipients. However, pre emptive therapy with ganciclovir makes this immunosuppressive effect transient and restricted to the time of infection duration.     

Significance of qualitative PCR detection method for preemptive therapy of cytomegalovirus infection in patients after allogeneic hematopoietic stem cell transplantation -- single-centre experience

Both early cytomegalovirus (CMV) monitoring and prophylactic antiviral therapy can decrease clinical complications or can prevent them in patients after allogeneic hematopoietic stem cell transplantation (HSCT). Presented paper summarizes experiences with using regular monitoring of reactivation of CMV after allogeneic HSCT by qualitative polymerase chain reaction (PCR) method to prevent the development of symptomatic CMV disease. Samples of peripheral blood leukocytes (PBL) in 71 patients were monitored. Because of retransplantation in two patients, 73 transplantations, each followed by the monitoring, were performed. Patients were monitored weekly after the transplantation for CMV DNA-emia in PBL. An episode of CMV infection representing an indication for preemptive ganciclovir (GCV) or foscarnet (FOS) therapy was defined as two consecutive positive PCR results in 4-7 days. Median time of monitoring was 313 days. The CMV infection was found in 28/73 monitorings (38.4%) and always was followed by preemptive therapy. One recurrence of CMV infection was observed in 4/28 (14.3%) monitorings and two recurrences in 1/28 (3.6%) monitorings. Presented approach resulted in complete prevention of overt CMV disease and this study enable to show that qualitative PCR method for determination of incipient CMV infection followed by preemptive therapy is suitable for preventing patients after allogeneic transplantation from CMV disease.