Acellular allogeneic nerve grafting combined with bone marrow mesenchymal stem cell transplantation for the repair of long-segment sciatic nerve defects:biomechanics and validation of mathematical models

We hypothesized that a chemically extracted acellular allogeneic nerve graft used in combination with bone marrow mesenchymal stem cell transplantation would be an effective treatment for long-segment sciatic nerve defects.To test this,we established rabbit models of 30 mm sciatic nerve defects,and treated them using either an autograft or a chemically decellularized allogeneic nerve graft with or without simultaneous transplantation of bone marrow mesenchymal stem cells.We compared the tensile properties,electrophysiological function and morphology of the damaged nerve in each group.Sciatic nerves repaired by the allogeneic nerve graft combined with stem cell transplantation showed better recovery than those repaired by the acellular allogeneic nerve graft alone,and produced similar results to those observed with the autograft.These findings confirm that a chemically extracted acellular allogeneic nerve graft combined with transplantation of bone marrow mesenchymal stem cells is an effective method of repairing long-segment sciatic nerve defects.

Tolerance and chimerism and allogeneic bone marrow/stem cell transplantation in liver transplantation

The liver has particular tolerogenic properties that allow its spontaneous acceptance in some animal species.Liver structure is considered to favor a tolerogenic environment.The peripheral tolerance mechanisms also play a role in spontaneous tolerance to liver graft.In a clinical setting,the main challenge nowadays facing liver transplantation is minimization of immunosuppression with the goal of donor-specific tolerance.Mechanisms involved in tolerance to transplanted organs are complex and partly unknown.A significant mechanism in tolerance induction is chimerism.Chimerism can be induced through transplantation of allogeneic donor bone marrow/stem cells under appropriate host conditioning.This review focuses on the tolerance mechanisms in liver transplantation and highlights the role of chimerism and allogeneic bone marrow/stem cell transplantation in tolerance development.

Alpha-GalCer Administration after Allogeneic Bone Marrow Transplantation Improves Immune Reconstitution in Mice

Objective To explore the effect of α-galactosyleramide （α-GalCer） on immune reconstitution under acute graft-versus-host disease （aGVHD）. Methods BALB/c mice were transplanted with allogeneic C57BL/6 bone marrow cells and splenocytes （both 1 × 10^7） after receiving lethal total-body irradiation, α-GalCer （100 ug/kg） or vehicle （dimethyl- sulfoxide） was administered intraperitoneally immediately after transplantation. The effects of α-GalCer on immune reconstitufion, proliferation of T cells and B cells, hematopoiesis, and thymic microenvironment were assessed. Results The α-GalCer group exhibited higher percentages of CD3^＋, CD4^＋, CD8^＋, B220^＋, CD40＋, and CD86＋cells compared with the vehicle group. The number of colony forming unit per 1000 CD34^＋ cells in the et-GalCer group was higher than in the vehicle group （P=0.0012）. In vitro proliferation assays showed that the α-GalCer group had higher percentages of CD3^＋, CD4^＋, CD8^＋, and B220^＋ cells compared with the vehicle group. As for the results of in vivo proliferation assays, the numbers of CD3^＋, CD4^＋, CD8^＋, and B220^＋ cells were higher in the α-GalCer group than in the normal group, especially the number of B220^＋ cells （P=0.007）. Significant difference was not found in thymocyte count between the α-GalCer group and the vehicle group, nor in the percentages of CD3^＋, CD4^＋, and CD8^＋ cells. Conclusion Administration of tl-GalCer after allogeneic bone marrow transplantation may promote immune reconstitution in the presence of aGVHD.

EFFECTS OF INTERLEUKIN-4 ON GRANULOCYTE-MACROPHAGE-COLONY FORMATION FROM MURINE BONE MARROW CELLS AND HEMATOPOIETIC RECONSTITUTION FOLLOWING MURINE ALLOGENEIC BONE MARROW TRANSPLANTATION

We investigated the effects of mouse recombinant IL-4 on hematopoiesis in vitro and in vivo. IL-4 alone was found to be incapable of stimulating colony formation, but it inhibited both IL-3-and GM-CSF-induced colony formation by murine hematopoietic progenitor cells. In contrast, colony formation induced by G-CSF was enhanced in the presence of IL-4. We also studied the influence of IL-4 on hematopoietic reconstiution after allogeneic bone marrow transplantation in a murine medel, and found that IL-4 had significant inhibitory effects on neutrophil recovery and that neutrophil recovery accelerated by IL-3 and G-CSF was significantly suppressed by IL-4. The combination of IL-4 and GM-SF caused a significant decrease in the absolute number of neutrophils.

Haploidentical Allogeneic Hematopoietic Stem Cell Transplantation for Thymoma-associated Severe Aplastic Anemia: a Case Report

THYMOMA, a relatively rare epithelial neoplasm with unique clinical and pathologic features, is the most usual diagnosis for a mass located in the mediastinum. It is often associated withautoimmune disorders. The myastnema gravls ano pure red cell aplasia are the most common disorders, with the incidences of 40% and 5%, respectively, while the incidence of aplastic anemia is only about 0-1.4%. 1 Thymectomy is hard to perform on patients with severe aplastic anemia（SAA） due to severe pancytopenia.

WJSC 6^(th) Anniversary Special Issues(1):Hematopoietic stem cell transplantation Allogeneic hematopoietic cell transplant for acute myeloid leukemia:Current state in 2013 and future directions

Acute myeloid leukemia(AML)represents a heterogeneous group of high-grade myeloid neoplasms of the elderly with variable outcomes.Though remissioninduction is an important first step in the management of AML,additional treatment strategies are essential to ensure long-term disease-free survival.Recent pivotal advances in understanding the genetics and molecular biology of AML have allowed for a risk-adapted approach in its management based on relapse-risk.Allogeneic hematopoietic cell transplantation(allo-HCT)represents an effective therapeutic strategy in AML providing the possibility of cure with potent graft-versus-leukemia reactions,with a demonstrable survival advantage in younger patients with intermediate-or poor-risk cytogenetics.Herein we review the published data regarding the role of allo-HCT in adults with AML.We searched MEDLINE/PubMed and EMBASE/Ovid.In addition,we searched reference lists of relevant articles,conference proceedings and ongoing trial databases.We discuss the role of allo-HCT in AML patients stratified by cytogenetic-and molecular-risk in first complete remission,as well as allo-HCT as an option in relapsed/refractory AML.Besides the conventional sibling and unrelated donor allografts,we review the available data and recent advances for alternative donor sources such as haploidentical grafts and umbilical cord blood.We also discuss conditioning regimens,including reduced intensity conditioning which has broadened the applicability of allo-HCT.Finally we explore recent advances and future possibilities and directions of allo-HCT in AML.Practical therapeutic recommendations have been made where possible based on available data and expert opinion.

Decitabine for Relapsed Acute Lymphoblastic Leukemia after Allogeneic Hematopoietic Stem Cell Transplantation

Relapse after allogeneic hematopoietic stem cell transplantation（allo-HSCT） remains a main question on treatment failure. Current strategies for management that usually include salvage chemotherapy, donor lymphocytic infusion and second transplantation. Our study assessed the efficacy of decitabine（DAC） for treating patients with acute lymphoblastic leukemia（ALL） who relapsed after allogeneic hematopoietic stem cell transplantation（allo-HSCT）. We retrospectively analyzed the outcomes of 12 patients with relapsed ALL after allo-HSCT who received DAC therapy. Nine patients received DAC combined with chemotherapy and donor stem cell infusion, and 3 patients received single-agent DAC. Ten of the 12 patients achieved complete remission（CR）, 1 achieved a partial remission（PR）, and 1 had no response（NR） after treatment at the latest follow-up（LFU）, the median survival was 11.2 months（range, 3.8–34, 7 months）. The 1-and 2-year overall survival（OS） rates were 50%（6/12） and 25%（3/12）, respectively. Five patients were still alive; 4 had maintained CR and 1 was alive with disease. Patients with Philadelphia chromosome-positive ALL had higher survival rate than patients with Philadelphia chromosome-negative ALL（57.1% vs. 20%）. No aggravated flares of graft-versus-host disease（GVHD） were observed during DAC treatment. Therefore, DAC may be a promising therapeutic agent for ALL recurrence after allo-HSCT.

Gut microbiome in allogeneic hematopoietic stem cell transplantation and specific changes associated with acute graft vs host disease

Allogeneic hematopoietic stem cell transplantation(aHSCT)is a standard validated therapy for patients suffering from malignant and nonmalignant hematological diseases.However,aHSCT procedures are limited by potentially life-threatening complications,and one of the most serious complications is acute graft-versus-host disease(GVHD).During the last decades,DNA sequencing technologies were used to investigate relationship between composition or function of the gut microbiome and disease states.Even if it remains unclear whether these microbiome alterations are causative or secondary to the presence of the disease,they may be useful for diagnosis,prevention and therapy in aHSCT recipients.Here,we summarized the most recent findings of the association between human gut microbiome changes and acute GVHD in patients receiving aHSCT.

Lymphocyte recovery is an independent predictor of relapse in allogeneic hematopoietic cell transplantation recipients for acute leukemia

AIM To examine the optimal absolute lymphocyte count(ALC) cut-off utilizing receiver operator characteristics(ROC) in addition to graft characteristics associated with early ALC recovery.METHODS Patients who received T-cell replete peripheral hematopoietic cell transplantation(HCT) for acute leukemia were identified. ALC cut-off was established using ROC analysis and subsequently the cohort was stratified. Time to endpoint analysis and cox regression modelling was computed to analyze outcomes. RESULTS A total of 72 patients met the inclusion criteria andwere analyzed. Optimal ALC cut-off was established to be on day 14(D14) with ALC > 0.3 × 10~9/L. At 2 years, cumulative incidence of relapse was 16.9% vs 46.9%(P = 0.025) for early and delayed lymphocyte recovery cohorts, respectively. Chronic graft vs host disease was more prevalent in the early lymphocyte recovery(ELR) group at 70% vs 27%, respectively(P = 0.0006). On multivariable analysis for relapse, ELR retained its prognostic significance with HR = 0.27(0.05-0.94, P = 0.038).CONCLUSION ELR is an independent predictor for relapse in patients receiving allogeneic HCT for acute leukemia. ELR was influenced by graft characteristics particularly CD34 count.

Clinical Utility of Molecular Diagnosis of Blood Stream Infections in Allogeneic Hematopoietic Stem Cell Transplantation Recipients with Hematologic Malignancies

Blood stream infections (BSIs) are a serious problem in patients with hematologic malignancies receiving allogeneic hematopoietic stem cell transplantation (ASCT). We evaluated the clinical utility of molecular diagnosis for the management of BSIs in such patients. We prospectively performed a polymerase chain reaction (PCR) analysis of microbial DNA in blood samples from 10 consecutive patients with hematological malignancies at least once a week for one month after ASCT. In total, 51 and 54 samples were analyzed by bacterial and fungal PCR assays, respectively. Bacteria were detected in 24 samples from 8 patients by PCR, but in only 2 samples from one patient by blood culture. Notably, the bacteria detected in at least half of the 24 samples were considered to have originated from the oral cavity. Fungi were detected in 5 samples from 3 patients by PCR, but not by blood culture. Most cases with positive PCR results were manageable with empirical antimicrobial therapy without disclosure of DNA data. Our DNA analyses did not directly contribute to management of BSIs, but did provide valuable microbiological evidence for the patients. Additionally, oral management appears to require a critical re-evaluation to reduce the occurrence of BSIs in ASCT recipients.

A comparison of flow cytometry detection of minimal residual disease and chimerism kinetics in chronic lymphocytic leukemia patients after allogeneic hematopoietic stem cell transplantation

Determination of minimal residual disease (MRD) remains crucial for the follow-up after therapy in chronic lymphocytic leukemia (CLL) patients. Chimerism was assessed by short tandem repeat (STR)-PCR and single nucleotide polymorphisms (SNP)-PCR, and MRD by a multicolor flow cytometric approach in 12 consecutive patients with CLL after they received allogeneic stem cell transplantation (SCT). Overall, 11 patients achieved MRD flow negativity [10 had full donor chimerism (FDC) and one had mixed chimerism (MC)]. Only one patient remained with MRD flow positivity and displayed MC. Fifty-six samples were concomitantly studied by both chimerism and MRD flow. A significant correlation was observed between MRD flow data and chimerism in both PB and BM by using a mixed effect linear regression (p < 0.001). Flow cytometry approach of MRD can be easily combined with chimerism during the follow-up post-allogeneic SCT. Both techniques appeared complementary for guiding post-transplant immunomodulation.

Review of allogeneic hematopoietic stem cell transplantation with reduced intensity conditioning in solid tumors excluding breast cancer

Solid tumors in adults constitute a heterogeneous group of malignancy originating from various organ systems. Solid tumors are not completely curable by chemotherapy, even though some subgroups are very chemo-sensitive. Recently, oncologists have focused on the use of allogeneic hematopoietic stem cell transplantation(alloHSCT) with reduced intensity conditioning(RIC) for the treatment of some refractory solid tumors. After the demonstration of allogeneic graft-versus-leukemia effect in patients with hematological malignancies who received allo-HSCT, investigators evaluated this effect in patients with refractory metastatic solid tumors. According to data from experimental animal models and preliminary clinical trials, a graft-versus-tumor(GvT) effect may also be observed in the treatment of some solid tumors(e.g., renal cell cancer, colorectal cancer, etc.) after allo-HSCT with RIC. The use of RIC regimens offers an opportunity of achieving full-donor engraftment with GvT effect, as well as, a reduced transplant-related mortality. Current literature suggests that allo-HSCT with RIC might become a choice for elderly and medically fragile patients with refractory metastatic solid tumors.

Ruxolitinib add-on in corticosteroid-refractory graft-vs-host disease after allogeneic stem cell transplantation:Results from a retrospective study on 38 Chinese patients

BACKGROUND Graft-vs-host disease (GVHD) is a major cause of mortality after allogeneic hematopoietic stem cell transplantation.Some patients have steroid-refractory(SR) GVHD.AIM To evaluate the effect and safety of ruxolitinib add-on in the treatment of patients with SR acute (a) and chronic (c) GVHD.METHODS We retrospectively analyzed 38 patients administered ruxolitinib add-on to standard immunosuppressive therapy for SR-aGVHD or SR-cGVHD following allogeneic hematopoietic stem cell transplantation.Ruxolitinib was administered5-10 mg/d depending on disease severity,patient status,and the use of antifungal drugs.Overall response rate,time to best response,malignancy relapse rate,infection rate,and treatment-related adverse events were assessed.RESULTS The analysis included 10 patients with SR-aGVHD (gradeⅢ/Ⅳ,n=9) and 28patients with SR-cGVHD (moderate/severe,n=24).For the SR-aGVHD and SRcGVHD groups,respectively:Median number of previous GVHD therapies was 2(range:1-3) and 2 (1-4);median follow-up was 2.5 (1.5-4) and 5 (1.5-10) mo;median time to best response was 1 (0.5-2.5) and 3 (1-9.5) mo;and overall response rate was 100%(complete response:80%) and 82.1%(complete response:10.7%) with a response observed in all GVHD-affected organs.The malignancy relapse rates for the SR-aGVHD and SR-cGVHD groups were 10.0%and 10.7%,respectively.Reactivation rates for cytomegalovirus,Epstein-Barr virus,and varicella-zoster virus,respectively,were 30.0%,10.0%,and 0%for the SR-aGVHD group and 0%,14.3%,and 7.1%for the SR-cGVHD group.CONCLUSION Ruxolitinib add-on was effective and safe as salvage therapy for SR-GVHD.

Optimal stem cell source for allogeneic stem cell transplantation for hematological malignancies

Hematopoietic stem cell transplant(HSCT) is a standard treatment for many hematological malignancies.Three different sources of stem cells, namely bone marrow(BM), peripheral blood stem cells(PBSC) and cord blood(CB) can be used for HSCT, and each has its own advantages and disadvantages. Randomized controlled trials(RCTs) suggest that there is no significant survival advantage of PBSC over BM in Human Leukocyte Antigen-matched sibling transplant for adult patients with hematological malignancies. PBSC transplant probably results in lower risk of relapse and hence better disease-free survival, especially in patients with high risk disease at the expense of higher risks of both severe acute and chronic graft-versus-host disease(GVHD).In the unrelated donor setting, the only RCT available suggests that PBSC and BM result in comparable overall and disease-free survivals in patients with hematological malignancies; and PBSC transplant results in lower risk of graft failure and higher risk of chronic GVHD.High level evidence is not available for CB in comparison to BM or PBSC. The risks and benefits of different sources of stem cells likely change with different conditioning regimen, strategies for prophylaxis and treatment of GVHD and manipulation of grafts. The recent success and rapid advance of double CB transplant and haploidentical BM and PBSC transplants further complicate the selection of stem cell source. Optimal selection requires careful weighing of the risks and benefits of different stem cell source for each individual recipient and donor. Detailed counseling of patient and donor regarding risks and benefits in the specific context of the patient and transplant method is essential for informed decision making.

Low WT1 transcript levels at diagnosis predicted poor outcomes of acute myeloid leukemia patients with t(8;21) who received chemotherapy or allogeneic hematopoietic stem cell transplantation

Background:Acute myeloid leukemia(AML) with t(8;21) is a heterogeneous disease.Identifying AML patients with t(8;21) who have a poor prognosis despite achieving remission is important for determining the best subsequent therapy.This study aimed to evaluate the impact of Wilm tumor gene-1(WT1) transcript levels and cellular homolog of the viral oncogene v-KIT receptor tyrosine kinase(C-KIT) mutations at diagnosis,and RUNXTRUNX1T1 transcript levels after the second consolidation chemotherapy cycle on outcomes.Methods:Eighty-eight AML patients with t(8;21) who received chemotherapy only or allogeneic hematopoietic stem cell transplantation(allo-HSCT) were included.Patients who achieved remission,received two or more cycles of consolidation chemotherapy,and had a positive measureable residual disease(MRD) test result(defined as <3-log reduction in RUNX1-RUNX1T1 transcript levels compared to baseline) after 2-8 cycles of consolidation chemotherapy were recommended to receive allo-HSCT.Patients who had a negative MRD test result were recommended to receive further chemotherapy up to only 8 cycles.WT1 transcript levels and C-KIT mutations at diagnosis,and RUNX1-RUNX1T1 transcript levels after the second consolidation chemotherapy cycle were tested.Results:Patients who had a C-KIT mutation had significantly lower WTl transcript levels than patients who did not have a C-KIT mutation(6.7%± 10.6%vs.19.5%± 19.9%,P < 0.001).Low WTl transcript levels(<5.0%) but not C-KIT mutation at diagnosis,a positive MRD test result after the second cycle of consolidation chemotherapy,and receiving only chemotherapy were independently associated with high cumulative incidence of relapse in all patients(hazard ratio[HR]= 3.53,2.30,and 11.49;95%confidence interval[CI]1.64-7.62,1.82-7.56,and 4.43-29.82;P = 0.002,0.034,and <0.001,respectively);these conditions were also independently associated with low leukemia-free survival(HR =3.71,2.33,and 5.85;95%CI 1.82-7.56,1.17-4.64,and 2.75-12.44;P < 0.001,0.016,and <0.001,respectively) and overall survival(HR = 3.50,2.32,and 4.34;95%CI 1.56-7.82,1.09-4.97,and 1.98-9.53;P = 0.002,0.030,and <0.001,respectively) in all patients.Conclusions:Testing for WTl transcript levels at diagnosis in patients with AML and t(8;21) may predict outcomes in those who achieve remission.A randomized study is warranted to determine whether allo-HSCT can improve prognosis in these patients.

The use of allogeneic cancellous bone graft in bone cavity of jaw cyst

A new method for filling bone cavity with a graft of frozen-decalcified-defatted-driedallogeneic (FDDDA) cancellous bone was described.This method was used for the treatment of cavi-ties after the enucleation of jaw cysts in 10 patients from December 1985 to February 1990.Thewounds of 9 patients healed by first intension,but wound infection occurred in one case postopera-tively.The 9 patients,besides the patient who suffered from wound infection,were followed up for5 to 56 months,with an average of 41.1 months.Evidence of recurrence with jaw cyst.was not ob-served.

A HIGHER INCIDENCE OF RELAPSE FOR ACUTE LYMPHOCYTIC LEUKEMIA TREATED WITH ALLOGENEIC HEMATOPOIETIC STEM CELL TRANSPLANTATION CONDITIONED WITH BU-CY_2 REGIMEN

Objective: To analyze long-term outcome in sixty leukemia patients received allogeneic hematopoietic stem cell transplantation (allo-HSCT) following busulfan and cyclophosphamide (BU-CY2) between 1994 and 2000. Methods: BU-CY2 was used as the conditioning regimen and allo-HSCT was performed for all patients. All the patients were followed-up until August 2001 or death. The leukemia-free survival, relapse and transplant-related mortality were discussed. Results: All 60 patients had sustained engraftment. Acute GVHD occurred in 22 out of 60 patients (36.7%), and the incidence of acute GVHD was 48% in the patients with CML, 30% in AML and 26.7% in ALL. 38 patients are still alive in continuous remission with a median follow-up of 30 months (range 12–84) and 22 patients have died. The main causes of death were acute GVHD in 3 patients, CMV-IP in 7 patients and relapse in 11 patients, the remaining one died of pulmonary infection. Among 11 patients who died of relapse, 8 patients with ALL relapsed in the early stage post transplant (8/15, 53.3%), relapse was observed in the remaining 3 patients with AML, and however, no relapse was observed in CML. The probability of disease-free survival at 3 years for CML. AML and ALL patients was 80%, 70% and 26.7%, respectively. Conclusion: This results suggests that BU-CY2 is an effective conditioning regimen in patients with AML and CML, resulting in a low relapse rate and high long-term survival rate, but not as effective in patients with ALL, with a higher incidence of relapse and therefore, not recommended for ALL patients.

OMISSION OF DAY +11 METHOTREXATE DOES NOT APPEAR TO INFLUENCE INCIDENCE AND SEVERITY OF GRAFT-VERSUS- HOST DISEASE AFTER ALLOGENEIC HEMATOPOIETIC STEM CELL TRANSPLANTATION

Objective: To explore the influence of omission of the day +11 dose of methotrexate (MIX) on the incidence and severity of graft-versus-host disease (GVHD) after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Methods: From April 1997 to October 2002, 80 leukemia patients (46 men and 34 women aged from 12 to 56 years with a median age of 35) underwent allo-HSCT at our BMT unit. Among them, 58 patients received grafts from HLA-identical siblings, 8 from HLA one major antigen mismatched siblings and 14 from HLA-matched unrelated donors. All patients received a modified cyclosporine and short-course MTX regimen for GVHD prophylaxis, which included MTX 15 mg on day +1, and 10 mg on days +3 and +6 (MTX day +11 dose omitted) and cyclosporine given daily. Results: The overall incidence of grade I~IV acute GVHD was 57.5% (46/80 patients), with grade II~IV acute GVHD in 28 patients (35%) and grade III~IV acute GVHD in 7 patients (8.8%). Among 58 patients receiving grafts from HLA-identical siblings, 24 patients developed grade I~IV acute GVHD (41.4%), with grade II~IV acute GVHD in 13 patients (22.4%) and grade III~IV acute GVHD in 4 patients (6.9%). 2l out of 22 patients receiving grafts from HLA one major antigen mismatched siblings and HLA-matched unrelated donors developed grade I~IV acute GVHD (95.5%), with grade II~IV acute GVHD in 14 patients (63.6%) and grade III~IV acute GVHD in 3 patients (13.6%). Chronic GVHD occurred in 38 out of 56 evaluable patients (67.9%), with extensive form in 15 patients (26.8%) and limited form in 23 patients (41.1%). With a median follow-up of 960 days (range 180~1980 days), the probability of leukemia-free survival at 3 years was 61.3% for all patients. Conclusion: Our results suggest that the day +11 MTX can be omitted without a major deleterious effect on the incidence and severity of graft-versus-host disease after HLA-identical sibling transplantation as well as HLA one major antigen mismatched sibling and HLA-matched unrelated donor transplantation.

CYTOMEGALOVIRUS INTERSTITIAL PNEUMONITIS FOLLOWING ALLOGENEIC PERIPHERAL BLOOD STEM CELL TRANSPLANTATION

Objective： To explore the risk factors and prophylaxis and treatment of cytomegalovirus interstitial pneumonitis （CMV-IP） after allogeneic peripheral blood stem cell transplantation （allo-PBSCT）. Methods： 43 patients who received allo-PBSCT were allocated to either a Gancyclovir（GCV）-prophylaxis group （n=19） or a non-GCV prophylaxis group （n=24）. A comparison was made of the incidence of CMV-IP in patients given or not given prophylactic gancyclovir. Results： 9 patients in non-GCV prophylaxis group developed late CMV-IP （P〈0.05）. Graft-versus-host-disease （GVHD） may be associated with a high risk of CMV-IP. 5 cases of CMV-IP were successfully treated with GCV, but 3 cases died of CMV-IP. The most common adverse event of GCV was neutropenia, but was reversible. Conclusion： CMV infection was a major cause of interstitial pneumonitis after allo-PBSCT, which correlated strongly with the severity of GVHD. Gancyclovir was shown to be effective in both prophylaxis and treatment of CMV-IP.