Predictors for persistent cytomegalovirus reactivation after T-cell-depleted allogeneic hematopoietic stem cell transplantation

Cytomegalovirus (CMV) reactivation occurs in up to 60% of CMV-seropositive recipients after allogeneic hematopoietic stem cell transplantation (HSCT). The incidence of CMV disease among T-cell-depleted HSCT patients has been reported from 5-15%. The incidence of reactivation refractory to antivirals in this population is not well studied. METHODS: In this retrospective study we characterized the outcome of CMV reactivation in a cohort of 255 adult and pediatric patients who underwent T-cell-depleted HSCT at Memorial Sloan-Kettering Cancer Center from September 1999 through August 2004. CMV infection was monitored by the pp65 antigenemia assay (CMV Ag). Persistent reactivation was defined as antigenemia positivity >21 days on antiviral therapy. RESULTS: Of 118 CMV-seropositive recipients, 69 (58.4%) had reactivated CMV. Twenty of 69 (29%) developed persistent reactivation at first episode of reactivation, and 7 (10%) in subsequent episode. All patients with persistent reactivation received >/=2 antivirals and CMV hyperimmune globulin; 45% received combination antiviral therapy. The median duration of persistent reactivation was 98 days, range 31-256 days. In multivariate analysis, maximum CMV Ag >25 cells/slide was associated with persistent reactivation (odds ratio 16.2%, 95% confidence interval 4-64, P<0.0001). CMV disease occurred in 6/27 (22%) patients with persistent reactivation. Patients with persistent reactivation had lower CD4(+) and CD8(+) lymphocyte counts compared with those with non-persistent reactivation at day +90 post HSCT (P=0.01 and 0.02, respectively). CONCLUSIONS: Persistent reactivation occurred in 39% of T-cell-depleted HSCT despite treatment with currently available antivirals. Maximum CMV Ag >25 cells/slide was associated with persistent CMV reactivation. More effective treatment modalities are needed for this high-risk population to reduce CMV-associated morbidity and mortality.     

Favorable impact of natural killer cell reconstitution on chronic graft-versus-host disease and cytomegalovirus reactivation after allogeneic hematopoietic stem cell transplantation

Natural killer cells are the first lymphocyte subset to reconstitute, and play a major role in early immunity after allogeneic hematopoietic stem cell transplantation. Cells expressing the activating receptor NKG2C seem crucial in the resolution of cytomegalovirus episodes, even in the absence of T cells. We prospectively investigated natural killer-cell reconstitution in a cohort of 439 adult recipients who underwent non-T-cell-depleted allogeneic hematopoietic stem cell transplantation between 2005 and 2012. Freshly collected blood samples were analyzed 3, 6, 12 and 24 months after transplantation. Data were studied with respect to conditioning regimen, source of stem cells, underlying disease, occurrence of graft-versus-host disease, and profiles of cytomegalovirus reactivation. In multivariate analysis we found that the absolute numbers of CD56^bright natural killer cells at month 3 were significantly higher after myeloablative conditioning than after reduced intensity conditioning. Acute graft-versus-host disease impaired reconstitution of total and CD56^dim natural killer cells at month 3. In contrast, high natural killer cell count at month 3 was associated with a lower incidence of chronic graft-versus-host disease, independently of a previous episode of acute graft-versus-host disease and stem cell source. NKG2C⁺CD56^dim and total natural killer cell counts at month 3 were lower in patients with reactivation of cytomegalovirus between month 0 and month 3, but expanded greatly afterwards. These cells were also less numerous in patients who experienced later cytomegalovirus reactivation between month 3 and month 6. Our results advocate a direct role of NKG2C-expressing natural killer cells in the early control of cytomegalovirus reactivation after allogeneic hematopoietic stem cell transplantation.     

Risk factors associated with late cytomegalovirus reactivation after allogeneic stem cell transplantation for hematological malignancies

We analyzed the clinical factors associated with late cytomegalovirus (CMV) reactivation in a group of 269 consecutive recipients of allogeneic stem cell transplant (SCT) for hematological malignancies. Eighty-four subjects (31%) experienced late CMV reactivation, including 64 with prior early reactivation and 20 with isolated late reactivation. Multivariate analyses were conducted in patients with early CMV reactivation to identify factors associated with late recurrence. Important risk factors included lymphoid diagnosis, occurrence of graft-versus-host disease (GVHD), greater number of episodes of early reactivation, persistent day 100 lymphopenia and the use of a CMV-seronegative donor graft. We combined these risk factors in a predictive model to identify those at relatively low, intermediate and high risk. The low-risk group (15% cumulative incidence, CI) encompassed patients without early CMV reactivation, and subjects transplanted for a myeloid malignancy from a matched-related (MR) donor without subsequent acute GVHD. The high-risk patients (73% CI) met all of the following criteria: (1) received an MR graft but developed GVHD, or received a non-MR graft irrespective of GVHD; (2) had more than two episodes of early reactivation; and (3) received a CMV-seronegative graft and/or remained persistently lymphopenic at day 100 after SCT. The remaining patients had an intermediate incidence of 32%.     

Immune reconstitution and tolerance after allogeneic hematopoietic stem cell transplantation

We have evaluated recovery of CD56 positive and other cell types following allogeneic stem cell transplantation and have found that the recovery of CD56 positive cells was faster than other lymphoid cells after allogeneic stem cell transplantation, while the recovery of CD4 positive cells was markedly delayed. Chimerism analysis showed that mixed chimerism was often observed in younger (<30 years old) patients. Mixed chimerism in older (> or =30 years old) patients was associated with rejection and relapse, while this was not found in younger patients. Among the chimerism of various cell populations, donor-derived CD56-positive cells are important in early engraftment when determined in allogeneic nonmyeloablative stem cell transplantation (allo-NST), regardless of the proportion of donor-derived CD3-positive cells. Complementarity-determining region three (CDR3) size spectratyping in T-cell receptor (TCR) chain subfamilies (Vbeta) showed that high level of diversity in TCR Vbeta repertoire is important for a late rejection and skewed TCR Vbeta repertoire is correlated with the occurrence of graft-versus-host disease (GVHD) especially chronic GVHD. Expression of inhibitory natural killer (NK) cell receptors such as CD158b and CD94/NKG2A on peripheral CD3-negative and -positive cells were increased in parallel with GVHD. Interestingly, these cells appeared to control GVHD, while preserving graft-versus-leukemia (GVL) effect. Analysis of cytokine gene expression in peripheral blood mononuclear cells showed that type 1 helper T cells (Th1)-derived cytokines increased in severe GVHD, while Th2-derived cytokines such as IL-4, IL-10 and IL-13 increased in mild GVHD. These results indicate that Th2 cells suppress GVHD, although Th1 cells augment GVHD. Taken together, evaluation of immune reconstitution and tolerance in patients receiving allogeneic stem cell transplantation from the various viewpoints is essential and useful to obtain better clinical outcome.     

Cytomegalovirus shapes long-term immune reconstitution after allogeneic stem cell transplantation

Immune reconstitution after allogeneic stem cell transplantation is a dynamic and complex process depending on the recipient and donor characteristics, on the modalities of transplantation, and on the occurrence of graft-versus-host disease. Multivariate methods widely used for gene expression profiling can simultaneously analyze the patterns of a great number of biological variables on a heterogeneous set of patients. Here we use these methods on flow cytometry assessment of up to 25 lymphocyte populations to analyze the global pattern of long-term immune reconstitution after transplantation. Immune patterns were most distinct from healthy controls at six months, and had not yet fully recovered as long as two years after transplant. The two principal determinants of variability were linked to the balance of B and CD8⁺ T cells and of natural killer and B cells, respectively. Recipient’s cytomegalovirus serostatus, cytomegalovirus replication, and chronic graft-versus-host disease were the main factors shaping the immune pattern one year after transplant. We identified a complex signature of under- and over-representation of immune populations dictated by recipient’s cytomegalovirus seropositivity. Finally, we identified dimensions of variance in immune patterns as significant predictors of long-term non-relapse mortality, independently of chronic graft-versus-host disease.     

Immune reconstitution to cytomegalovirus after allogeneic hematopoietic stem cell transplantation: impact of host factors,drug therapy,and subclinical reactivation

Reconstitution of cellular immunity by 3 months after hematopoietic stem cell transplantation (HSCT) is a critical determinant of the long-term success of the transplantation. We analyzed the factors affecting recovery of cytomegalovirus (CMV)-specific CD4+ and CD8+ function at 3 months after HSCT by univariate and multivariable analyses including source of stem cells (bone marrow vs peripheral blood stem cells [PBSCs]), age, sex, graft-versus-host disease (GVHD), steroid use, conditioning regimens, ganciclovir use, HLA matching, circulating CMV antigenemia, absolute CD4+ and CD8+ counts, and donor CMV serology. High-dose steroids and CD4+ count less than 100 x 10(9)/L were significant predictors of impaired CD4+ functional recovery in the multivariable analysis. High-dose steroids, bone marrow as a source of stem cells, and CD8+ count less than 50 x 10(9)/L were associated with impaired CD8+ function in the multivariable analysis. Steroids were found to impair both CD4+ and CD8+ function in a dose-dependent manner. In the absence of high-dose steroids, low-level subclinical CMV antigenemia was found to stimulate both CD4+ and CD8+ functional recovery in recipients of ganciclovir prophylaxis. There was no difference in immune reconstitution between those who received prophylactic ganciclovir versus antigenemia-guided pre-emptive therapy. Thus, absolute CD4+ and CD8+ counts less than 100 x 10(9)/L and 50 x 10(9)/L, respectively; bone marrow as the source of stem cells; and high-dose steroid use all predict delayed recovery of functional T-cell immunity at 3 months after transplantation. Subclinical CMV reactivation while on ganciclovir appears to be a potent stimulator of T-cell function. These findings have implications for vaccination and adoptive-immunotherapy strategies in this population.     

Guillain–Barré syndrome associated with cytomegalovirus infection after allogeneic hematopoietic stem cell transplantation

The association between cytomegalovirus (CMV) infection and the development of Guillain-Barré syndrome (GBS) in the setting of allogeneic hematopoietic stem cell transplantation (alloSCT) has been reported only occasionally. We describe here a 23-year-old patient diagnosed with acute myelogenous leukemia who underwent a partially HLA-mismatched alloSCT and soon after developed GBS along with a CMV infection. Serum autoantibodies to several ganglioside antigens were concomitantly detected. Despite therapy with ganciclovir and plasma exchanges, the patient's clinical condition rapidly deteriorated, and he died 3 weeks later with persisting CMV antigenemia. Although a coincidental association cannot be excluded, it could be speculated that a pathogenetic link exists between the 2 disorders. In this sense, molecular mimicry between viral antigens and neural host tissues could be postulated as the hypothetical mechanism underlying the triggering of the autoimmune disease in the present case.     

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...     

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     

Tetramer monitoring to assess risk factors for recurrent cytomegalovirus reactivation and reconstitution of antiviral immunity post allogeneic hematopoietic stem cell transplantation

S. Borchers, S. Luther, U. Lips, N. Hahn, J. Kontsendorn, M. Stadler, S. Buchholz, H. Diedrich, M. Eder, U. Koehl, A. Ganser, E. Mischak‐ Weissinger. Tetramer monitoring to assess risk factors for recurrent cytomegalovirus reactivation and reconstitution of antiviral immunity post allogeneic hematopoietic stem cell transplantation.
Transpl Infect Dis 2011: 13: 222–236. All rights reserved Background. Reactivation of cytomegalovirus (CMV) is a major cause of morbidity after allogeneic hematopoietic stem cell transplantation (HSCT). In healthy individuals, virus‐specific T cells (CMV‐CTL) control the reactivation of latent CMV. The monitoring of virus‐epitope‐binding CD8⁺ T cells using major histocompatibility complex‐I‐peptide complexes (tetramers) has recently been established, allowing assessment of the reconstitution of CMV‐CTL post HSCT. Patients and methods. In order to study immune reconstitution and reactivation control through CMV‐CTL, we regularly monitored all patients undergoing allogeneic HSCT in our department for 2 years, who matched at least 1 of 6 commercially available tetramers for common human leukocyte antigen (HLA) types. To verify risk factors for CMV reactivations in our cohorts, clinical characteristics of all patients transplanted within the last 10 years were included in statistical analyses determining the relative risk for single and recurrent CMV reactivations. Results. As expected, CMV serostatus, HLA match, and donor source significantly influenced the risk of recurrent CMV reactivation. Applying CMV‐CTL tetramer monitoring for 2 years allowed the monitoring of 114 (85%) of 134 patients, by testing a set of tetramers representing 6 epitopes from 3 different CMV proteins. The presence of CMV‐CTL before day +50 and their expansion post reactivation seem to protect against recurrent CMV reactivations. The mean number of CMV‐CTL by day +100 was >5‐fold higher in the recipient CMV‐positive/donor‐positive (R+/D+) group (91/μL) compared with the R+/D? (13/μL) and the R?/D+(2/μL) group. Seventy‐nine percent of patients from the R+/D+ setting recovered >10 CMV‐CTL per μL by day +100, while almost 50% of the other groups failed to mount a CMV‐specific response by that time (R+/D?: 58%; R?/D+: 43%). Conclusion. Tetramer monitoring can help to predict (recurrent) CMV reactivation and is a useful approach to monitor individual patients with increased risk for recurrent reactivation post HSCT; thus, it could help to identify patients in need of adoptive transfer of CMV‐CTL or to optimize the use of antiviral drugs.     

Severe hypophosphatemia during hematopoietic reconstitution after allogeneic peripheral blood stem cell transplantation

A patient suffering from acute myeloid leukemia (FAB M5a) received a PBSC allograft from a matched, related donor. On day 13 after transplantation severe hypophosphatemia (0.21 mmol/l) was first noted which persisted irrespective of intravenous phosphate administration, and within 2 days reached concentrations below 0.13 mmol/l. After repeated phosphate substitution serum phosphate returned to 1.40 mmol/l on day 17. Phosphate in urine, and calcium in serum were recorded as unchanged throughout. Clinical signs and symptoms due to severe hypophosphatemia were not observed except for paresthesia in the lower extremities. The precipitous fall in serum phosphate coincided with hematopoietic reconstitution as reflected by a steep rise in leukocyte count from 0.08 x 109/l on day 10 to 5. 94 x 109/l on day 15 after transplantation. Thus, isolated hypophosphatemia was likely the result of excessive cellular phosphate uptake during hematopoietic reconstitution. Electrolyte monitoring after PBSCT should include serum phosphate to identify the hypophosphatemia associated with hematopoietic recovery.     

New tools in assessing immune reconstitution after hematopoietic stem cell transplantation

BACKGROUND AND OBJECTIVES: Immune functions are impaired after allogeneic stem cell transplantation for several months depending on the age of the recipient, initial pathology, degree of HLA and minor histocompatibility antigens mismatches, origin and manipulation of the graft (unmanipulated or T-cell depleted bone marrow transplantation, cord blood) and post-transplantation events (acute or chronic graft-versus-host disease, relapse and infectious complications). MATERIAL AND METHODS, RESULTS AND CONCLUSION: In addition to lymphocyte phenotyping and functional assays, new tools are now available to monitor specific aspects of the immune response in the follow-up of hematopoietic stem cell transplantation: reconstitution of T cell diversity (spectratyping or Immunoscope), thymic function (TREC or "T-cell receptor rearrangement excision DNA circles") and antigen-specific T cell responses (HLA tetramers).     

Sirolimus-based graft-versus-host disease prophylaxis protects against cytomegalovirus reactivation after allogeneic hematopoietic stem cell transplantation: a cohort analysis

Sirolimus-based immunosuppressive regimens in organ transplantation have been associated with a lower than expected incidence of cytomegalovirus (CMV) disease. Whether sirolimus has a similar effect on CMV reactivation after allogeneic hematopoietic stem cell transplantation (HSCT) is not known. We evaluated 606 patients who underwent HSCT between April 2000 and June 2004 to identify risk factors for CMV reactivation 100 days after transplantation. The cohort included 252 patients who received sirolimus-tacrolimus for graft-versus-host disease (GVHD) prophylaxis; the rest received non-sirolimus-based regimens. An initial positive CMV DNA hybrid capture assay was observed in 225 patients (37.1%) at a median 39 days after HSCT for an incidence rate of 0.50 cases/100 patient-days (95% confidence interval [CI], 0.44-0.57). Multivariable Cox modeling adjusting for CMV donor-recipient serostatus pairs, incident acute GVHD, as well as other important covariates, confirmed a significant reduction in CMV reactivation associated with sirolimus-tacrolimus-based GVHD prophylaxis, with an adjusted HR of 0.46 (95% CI, 0.27-0.78; P = .004). The adjusted HR was 0.22 (95% CI, 0.09-0.55; P = .001) when persistent CMV viremia was modeled. Tacrolimus use without sirolimus was not significantly protective in either model (adjusted HR, 0.66; P = .14 and P = .35, respectively). The protective effect of sirolimus-containing GVHD prophylaxis regimens on CMV reactivation should be confirmed in randomized trials.     

Long-term ultra-low-dose acyclovir against varicella-zoster virus reactivation after allogeneic hematopoietic stem cell transplantation

To evaluate the efficacy of long-term prophylaxis with ultra-low-dose acyclovir against varicella-zoster virus (VZV) reactivation, we analyzed the records of 242 Japanese adult patients who underwent allogeneic hematopoietic stem cell transplantation for the first time from 1995 to 2006 at our hospital. We started long-term oral acyclovir at 200 mg/day in July 2001. Acyclovir was continued until the end of immunosuppressive therapy and at least 1 year after transplantation. Sixty-six patients developed VZV reactivation at a median of 248 days after HSCT, with a cumulative incidence of 34.7%. Only one breakthrough reactivation occurred during long-term acyclovir, which responded well to therapeutic dose of valacyclovir. The use of long-term acyclovir was the only independent determinant that significantly decreased the overall incidence of VZV reactivation (20% vs. 50%, P < 0.0001). With this prophylaxis, visceral dissemination and serious complications other than post-herpetic neuralgia was completely eliminated, and thereby need for hospitalization was significantly reduced (21% vs. 71%, P = 0.0034). Fifteen of the 57 patients who discontinued acyclovir developed VZV reactivation, with a cumulative incidence of 32.1%. VZV reactivation following discontinuation tended to occur in patients who were receiving immunosuppressive therapy at the cessation of acyclovir. These findings suggested that long-term prophylaxis of ultra-low-dose acyclovir resulted in a successful prevention of severe VZV-related symptoms and death, with a significantly decreased overall incidence of VZV reactivation. Prolongation of prophylactic acyclovir on profound immunosuppression might be important for thorough suppression of VZV reactivation.     

Hepatitis B virus reactivation in patients with HBs antibodies after allogeneic hematopoietic stem cell transplantation

We retrospectively investigated the clinical characteristics of reactivation of hepatitis B (HB) virus after allogeneic hematopoietic stem cell transplantation (HSCT). Of 2002 patients who received transplantation between January 1994 and December 2004, seven patients who were anti-HB surface antibody (anti-HBs) positive and HB surface antigen (HBs-Ag) negative developed reactivation of the HB virus after allogeneic HSCT. The patients' median age was 49 years, and they consisted of 5 males and 2 females. Six of 7 recipients received hematopoietic stem cells from HLA-identical sibling donors. All donors were negative for HBs-Ag. Six donors were negative for anti-HBs and one donor was not investigated for anti-HBs. HB reactivation occurred 5 to 29 (median 15) months after HSCT. Chronic graft-versus-host-disease (GVHD) was observed in 5 cases. The peak value of GPT during HB reactivation varied from 83 to 1930 (median 318) IU/l. Lamivudine was given to 5 patients. One patient was treated with supportive therapy and other one patient was observed without treatment. Two patients developed fulminant hepatitis and died of hepatic dysfunction. Clinicians should consider the possibility of HB reactivation in anti-HBs-positive patients. The establishment of a preventive method for HB reactivation would be desirable.     

Influence of the hematopoietic stem cell source on early immunohematologic reconstitution after allogeneic transplantation

Several acute hemolysis episodes, sometimes lethal, have been recently described after transplantation of allogeneic peripheral blood hematopoietic stem cells (PBHSCs). Hemolysis resulted from the production of donor-derived antibodies (Abs) directed at ABO antigens (Ags) present on recipient red blood cells (RBCs). A multicenter randomized phase III clinical study comparing allogeneic PBHSC transplantation (PBHSCT) versus bone marrow hematopoietic stem cell transplantation (BMHSCT) has been conducted in France. In the course of this study, serum anti-A and/or anti-B Ab titers were compared before the conditioning regimen and on day +30 after transplantation in 49 consecutive evaluable PBHSCT (n = 21) or BMHSCT (n = 28) recipients. PBHSCT resulted in a higher frequency of increased anti-A and/or anti-B Ab titers 30 days after transplantation as compared to BMHSCT: 8 (38%) of 21 versus 3 (11%) of 28 (P =.04). In PBHSCT recipients, increased titers were observed mostly after receiving a minor ABO mismatch transplant: 5 of 7 versus 3 of 14 in the absence of any minor ABO mismatch (P =.05), whereas this was not the case after BMHSCT: 1 of 8 versus 2 of 20. Anti-A and/or anti-B serum Abs detectable at day +30 after PBHSCT were always directed against A and/or B Ags absent both on donor and recipient RBCs. Finally, 3 of 21 PBHSCT versus 0 of 28 BMHSCT recipients developed anti-allogeneic RBC Abs other than ABO (P =.07). Overall, the data strongly suggest that immunohematologic reconstitution differs significantly after granulocyte colony-stimulating factor-mobilized PBHSCT when compared to BMHSCT. Such a difference could contribute to the acute hemolysis described after PBHSCT as well as to distinct alloreactivity after PBHSCT.