COVID-19 impact in Crohn’s disease patients submitted to autologous hematopoietic stem cell transplantation

BACKGROUND Severe acute respiratory syndrome coronavirus 2 is the virus responsible for coronavirus disease 2019(COVID-19),a disease that has been blamed for inducing or exacerbating symptoms in patients with autoimmune diseases.Crohn's disease(CD)is an inflammatory bowel disease that affects genetically susceptible patients who develop an abnormal mucosal immune response to the intestinal microbiota.Patients who underwent hematopoietic stem cell transplantation(HSCT)are considered at risk for COVID-19.AIM To describe for the first time the impact of COVID-19 in CD patients who had undergone autologous,non-myeloablative HSCT.METHODS In this descriptive study a series of 19 patients were diagnosed with positive COVID-19.For two patients there were reports of the occurrence of two infectious episodes.Parameters related to HSCT,such as time elapsed since the procedure,vaccination status,CD status before and after infection,and clinical manifestations resulting from COVID-19,were evaluated.RESULTS Among the patients with COVID-19,three,who underwent Auto HSCT less than six months ago,relapsed and one,in addition to the CD symptoms,started to present thyroid impairment with positive anti-TPO.Only one of the patients required hospitalization for five days to treat COVID-19 and remained in CD clinical remission.Nine patients reported late symptoms that may be related to COVID-19.There were no deaths,and a statistical evaluation of the series of COVID-19 patients compared to those who did not present any infectious episode did not identify significant differences regarding the analyzed parameters.CONCLUSION Despite the change in CD status in three patients and the presence of nine patients with late symptoms,we can conclude that there was no significant adverse impact concerning COVID-19 in the evaluated patients who underwent HSCT to treat CD.

Allogeneic stem cell transplantation in the treatment of acute myeloid leukemia: An overview of obstacles and opportunities

As an important treatment for acute myeloid leukemia, allogeneic hematopoietic stem cell transplantation(allo-HSCT) plays an important role in reducing relapse and improving long-term survival. With rapid advancements in basic research in molecular biology and immunology and with deepening understanding of the biological characteristics of hematopoietic stem cells, allo-HSCT has been widely applied in clinical practice. During allo-HSCT, preconditioning, the donor, and the source of stem cells can be tailored to the patient’s conditions, greatly broadening the indications for HSCT, with clear survival benefits. However, the risks associated with allo-HSCT remain high, i.e. hematopoietic reconstitution failure, delayed immune reconstitution, graft-versus-host disease, and posttransplant relapse, which are bottlenecks for further improvements in allo-HSCT efficacy and have become hot topics in the field of HSCT. Other bottlenecks recognized in the current treatment of individuals diagnosed with acute myeloid leukemia and subjected to allo-HSCT include the selection of the most appropriate conditioning regimen and post-transplantation management. In this paper, we reviewed the progress of relevant research regarding these aspects.

Sarcopenia and gut microbiota alterations in patients with hematological diseases before and after hematopoietic stem cell transplantation

Objective: The aim of this study was to investigate the prevalence of sarcopenia(SP) and its relationship with gut microbiota alterations in patients with hematological diseases before and after hematopoietic stem cell transplantation(HSCT).Methods: A total of 108 patients with various hematological disorders were selected from Peking University People’s Hospital. SP was screened and diagnosed based on the 2019 Asian Sarcopenia Diagnosis Strategy. Physical measurements and fecal samples were collected, and 16S rRNA gene sequencing was conducted. Alpha and beta diversity analyses were performed to evaluate gut microbiota composition and diversity.Results: After HSCT, significant decreases in calf circumference and body mass index(BMI) were observed,accompanied by a decline in physical function. Gut microbiota analyses revealed significant differences in the relative abundance of Enterococcus, Bacteroides, Blautia and Dorea species before and after HSCT(P<0.05). Before HSCT, sarcopenic patients had lower Dorea levels and higher Phascolarctobacterium levels than non-sarcopenia patients(P<0.01). After HSCT, no significant differences in species abundance were observed. Alpha diversity analysis showed significant differences in species diversity among the groups, with the highest diversity in the postHSCT 90-day group and the lowest in the post-HSCT 30-day group. Beta diversity analysis revealed significant differences in species composition between pre-and post-HSCT time points but not between SP groups. Linear discriminant analysis effect size(LEfSe) identified Alistipes, Rikenellaceae, Alistipes putredinis, Prevotellaceae defectiva and Blautia coccoides as biomarkers for the pre-HSCT sarcopenia group. Functional predictions showed significant differences in anaerobic, biofilm-forming and oxidative stress-tolerant functions among the groups(P<0.05).Conclusions: This study demonstrated a significant decline in physical function after HSCT and identified potential gut microbiota biomarkers and functional alterations associated with SP in patients with hematological disorders. Further research is needed to explore the underlying mechanisms and potential therapeutic targets.

Ocular manifestations and quality of life in patients after hematopoietic stem cell transplantation

AIM:To explore the relationship between ocular and systemic conditions and the impact of ocular complications on the quality of life(QOL)in patients after allogeneic hematopoietic stem cell transplantation(ALLO-HSCT).METHODS:Forty-four patients with severe hematopoietic disease were enrolled after ALLO-HSCT at our center from July 2018 to October 2020.They completed two questionnaires:the Ocular Surface Disease Index(OSDI)and the quality-of-life scale for Chinese patients with visual impairment(SQOL-DV1).Ocular conditions and systemic conditions were also assessed.RESULTS:Eye damage was correlated with total bilirubin(P=0.005),and gamma-glutamyl transferase(GGT)(P=0.021).There was no significant correlation between the overall QOL score and OSDI(P=0.8226)or SQOLDV1(P=0.9526)scores.The OSDI and the overall QOL score were not correlated with ocular conditions,including best-corrected visual acuity(BCVA),intraocular pressure,Schirmer tear test II,sodium fluorescein staining,tear film breakup time,and tear meniscus height.SQOLDV1 was correlated with BCVA(P=0.0007),sodium fluorescein staining(P=0.007),and tear film breakup time(P=0.0146).CONCLUSION:In some patients,early ocular symptoms are not evident after ALLO-HSCT,while ocular surface complications can be observed after a comprehensive ophthalmological examination.Especially for those with elevated total bilirubin or GGT,regular ophthalmic follow-up visits are essential to diagnose and treat ocular graft versus host disease(o GVHD),especially for patients with elevated total bilirubin or GGT.

Hematopoietic stem cell transplantation of aplastic anemia by relative with mutations and normal telomere length: A case report

BACKGROUND Immunosuppressive therapy and matched sibling donor hematopoietic stem cell transplantation(MSD-HSCT)are the preferred treatments for aplastic anemia(AA).CASE SUMMARY In this report,we describe a 43-year-old male patient with severe AA who carried BRIP1(also known as FANCJ),TINF2,and TCIRG1 mutations.Screening of the family pedigree revealed the same TINF2 mutation in his mother and older brother,with his older brother also carrying the BRIP1 variant and demonstrating normal telomere length and hematopoietic function.The patient was successfully treated with oral cyclosporine A,eltrombopag,and acetylcysteine,achieving remission 4 years after receiving MSD-HSCT from his older brother.CONCLUSION This case provides a valuable clinical reference for individuals with suspected pathogenic gene mutations,normal telomere length,and hematopoietic function,highlighting them as potential donors for patients with AA.

Advantageous tactics with certain probiotics for the treatment of graft-versus-host-disease after hematopoietic stem cell transplantation

Hematopoietic stem cell transplantation(HSCT)becomes a standard form of cellular therapy for patients with malignant diseases.HSCT is the first-choice of immunotherapy,although HSCT can be associated with many complications such as graft-versus-host disease(GVHD)which is a major cause of morbidity and mortality after allogeneic HSCT.It has been shown that certain gut microbiota could exert protective and/or regenerative immunomodulatory effects by the production of short-chain fatty acids(SCFAs)such as butyrate in the experimental models of GVHD after allogeneic HSCT.Loss of gut commensal bacteria which can produce SCFAs may worsen dysbiosis,increasing the risk of GVHD.Expression of G-protein coupled receptors such as GPR41 seems to be upre-gulated in the presence of commensal bacteria,which might be associated with the biology of regulatory T cells(Tregs).Treg cells are a suppressive subset of CD4 positive T lymphocytes implicated in the prevention of GVHD after allogeneic HSCT.Here,we discuss the current findings of the relationship between the modification of gut microbiota and the GVHD-related immunity,which suggested that tactics with certain probiotics for the beneficial symbiosis in gut-immune axis might lead to the elevation of safety in the allogeneic HSCT.

Donor-Derived CD19-Targeted T Cell Infusion Eliminates B Cell Acute Lymphoblastic Leukemia Minimal Residual Disease with No Response to Donor Lymphocytes after Allogeneic Hematopoietic Stem Cell Transplantation

Leukemia relapse is still the leading cause of treatment failure after allogeneic hematopoietic stem cell transplantation (allo-HSCT) for B cell acute lymphoblastic leukemia (B-ALL). Relapsed patients with BALL after allo-HSCT have a very short median survival. Minimal residual disease (MRD) is predictive of forthcoming hematological relapse after hematopoietic stem cell transplantation (HSCT);furthermore, eliminating MRD effectively prevents relapse. Donor lymphoblastic infusion (DLI) is the main established approach to treat B-ALL with MRD after allo-HSCT. However, about one-third of patients with MRD are non-responsive to DLI and their prognosis worsens. Although donor-derived cluster of differentiation (CD)19-directed chimeric antigen receptor-modified (CAR) T cells (CART19s) can potentially cure leukemia, the efficiency and safety of infusions with these cells have not yet been investigated in patients with MRD after HSCT. Between September 2014 and February 2018, six patients each received one or more infusions of CART19s from HSCT donors. Five (83.33%) achieved MRD-negative remission, and one case was not responsive to the administration of CAR T cells. Three of the six patients are currently alive without leukemia. No patient developed acute graft-versus-host disease (aGVHD), and no patient died of cytokine release syndrome. Donor-derived CAR T cell infusions seem to be an effective and safe intervention for patients with MRD in B-ALL after allo-HSCT and for those who were not responsive to DLI.

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.

Umbilical Cord Blood-derived Mesenchymal Stem Cells Ameliorate Graft-Versus-Host Disease Following Allogeneic Hematopoietic Stem Cell Transplantation through Multiple Immunoregulations

Summary： Although mesenchymal stem cells （MSCs） are increasingly used to treat graft-versus-host disease （GVHD）, their immune regulatory mechanism in the process is elusive. The present study aimed to investigate the curative effect of third-party umbilical cord blood-derived human MSCs （UCB-hMSCs） on GVHD patients after allogeneic hematopoietic stem cell transplantation （allo-HSCT） and their immune regulatory mechanism. Twenty-four refractory GVHD patients after allo-HSCT were treated with UCB-hMSCs. Immune cells including T lymphocyte subsets, NK ceils, Treg cells and dendritic cells （DCs） and cytokines including interleukin-17 （IL-17） and tumor necrosis factor-alpha （TNF-α） were monitored before and after MSCs transfusion. The results showed that the symptoms of GVHD were alleviated significantly without increased relapse of primary disease and transplant-related complications after MSCs transfusion. The number of CD3^＋, CD3＋CD4^＋ and CD3＋CD8^＋ cells decreased significantly, and that of NK cells remained unchanged, whereas the number of CD4^＋ and CD8^＋ Tregs increased and reached a peak at 4 weeks; the number of mature DCs, and the levels of TNF-α and IL-17 decreased and reached a trough at 2 weeks. It was concluded that MSCs ameliorate GVHD and spare GVL effect via immunoregulations.

Prophylactic antiviral therapy in allogeneic hematopoietic stem cell transplantation in hepatitis B virus patients

AIM: To investigate the timing, safety and efficacy of prophylactic antiviral therapy in patients with hepatitis B virus(HBV) infection undergoing allogeneic hematopoietic stem cell transplantation(allo-HSCT).METHODS: This prospective study recruited a total of 57 patients diagnosed with malignant hematological diseases and HBV infection at the First Affiliated Hospital of Sun Yat-sen University between 2006 and 2013.The patients were classified as hepatitis B surface antigen(HBs Ag)-positive or HBs Ag-negative/ anti HBcpositive.Patients were treated with chemotherapy followed by antiviral therapy with nucleoside analogues.Patients underwent allo-HSCT when serum HBV DNA was < 103 IU/mL.Following allo-HSCT, antiviral therapy was continued for 1 year after the discontinuation of immunosuppressive therapy.A total of 105 patients who underwent allo-HSCT and had no HBV infection were recruited as controls.The three groups were compared for incidence of graft-vs-host disease(GVHD), drug-induced liver injury, hepatic veno-occlusive disease, death and survival time.RESULTS: A total of 29 of the 41 subjects with chronic GVHD exhibited extensive involvement and 12 exhibited focal involvement.Ten of the 13 subjects with chronic GVHD in the HBs Ag(-)/hepatitis B core antibody(+) group exhibited extensive involvement and 3 exhibited focal involvement.Five of the 10 subjects with chronic GVHD in the HBs Ag(+) group exhibited extensive involvement and 5 exhibited focal involvement.The non HBV-infected group did not differ significantly from the HBs Ag-negative/anti HBc-positive and the HBs Ag-positive groups which were treated with nucleoside analogues in the incidence of graft-vs-host disease(acute GVHD; 37.1%, 46.9% and 40%, respectively; P = 0.614; chronic GVHD; 39%, 40.6% and 40%, respectively; P = 0.98), drug-induced liver injury(25.7%, 18.7% and 28%, respectively; P = 0.7),death(37.1%, 40.6% and 52%, respectively; P = 0.4) and survival times(P = 0.516).One patient developed HBV reactivation(HBs Ag-positivity) due to early discontinuation of antiviral therapy.CONCLUSION: Suppression of HBV DNA to < 103 IU/m L before transplantation, continued antiviral therapy and close monitoring of immune markers and HBV DNA after transplantation may assure the safety of alloHSCT.

Allogeneic Peripheral Blood Hematopoietic Stem Cell Transplantation for Patients with Hematologic Malignancies

To investigate the therapeutic effects and associated complications of allogeneic peripheral blood stem cell transplantation （allo-PBSCT）, 40 patients with various malignant hematopoietic diseases received allo-PBSCT. The preparative regimens were based on BUCY2 or modified BUCY2, The acute graft-versus host disease （aGVHD） was prevented by cyclosporin A and shortterm MTX regimen in all patients. Two patients from donors with one fully mismatched HLA on DRB1 locus and 4 from unrelated donor also administered Zenapox （CD25 MAb） at dosage of 1 rag/ kg every day on the day before transplantation and day 4 after transplantation. These 6 patients were also treated with mycophenolate mofetil （MMF）. Transfusion of the donor cells： The median of the transfused nucleated cells was 5.38×10^8/kg and that of the CD34^＋ cells was 7.8×10^6/kg respectively. All the patients gained hematopoietic reconstruction except one who died of infection before engraftment. Seven patients got Ⅱ°-Ⅳ° aGVHD and the incidence was 17.5 %. Fourteen patients got cGVHD and the incidence was 53.8 % in the patients who survived over 6 months. Twenty-eight patients had fever or other characteristics of infection. The median follow-up time was 13.8 months. The incidence of transplantation related mortality （TRM） was 17.5 %and 2 patients relapsed （5.0 %）. It was concluded that allo-PBSCT can reconstruct hematopoiesis quickly and is a favorable therapeutic method for leukemia.

Allogeneic hematopoietic stem cell transplantation for patients with acute leukemia

Objective： The purposes of this study were to assess the efficacy of allogeneic hematopoietic stem cell transplantation （HSCT） for acute leukemia （AL） and analyze the factors affecting the prognosis of these patients. Methods： The clinical and follow-up data of 93 AL patients （median age, 30 years） undergoing allogeneic HSCT in Xiangya Hospital over the past 12 years were collected, and the potential factors affecting the efficacy and prognosis of allogeneic HSCT patients were determined. Results： Hematopoietic reconstitution was achieved in 90 patients. At the last follow-up, the incidences of severe acute graft versus host disease （aGvHD） and extensive chronic GvHD （cGvHD） were 14.0% and 20.0%, the 3-year cumulative incidence of transplantation related mortality （TRM） and relapse rate were 16.8%±6.1% and 21.3%±6.7%, and the estimated 3-year overall survival （OS） and disease-free survival （DFS） of the patients were 64.6%±5.4% and 56.5%±5.5%, respectively. Univariate analysis indicated that age older than 40 years, HLA mismatch, and severe lung infection within the first 100 days after transplantation were risk factors for severe aGvHD, age older than 40 years, HLA mismatch, severe lung infection within the first 100 days after transplantation, and severe aGvHD were risk factors for TRM, high-risk AL and lack of cGvHD were risk factors for relapse （all P〈0.05）. Survival estimation showed that HLA mismatch, severe lung infection occurring within the first 100 days post-transplantation, high-risk AL severe aGvHD and lack of cGvHD were risk factors associated with poor prognosis （all P〈0.05）. Further multivariate analyses revealed that severe lung infection within the first 100 days post-transplantation, severe aGvHD and lack of cGvHD were independent risk factors for unfavorable outcomes （all P〈0.05）. Conclusions： Allogeneic HSCT can improve the DFS of AL patients, and severe lung infection within the first 100 days post-transplantation, severe aGvHD and lack of cGvHD are independent risk factors affecting the prognosis.

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.

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.

Analysis of Seizure Risk Factors after Allogeneic Hematopoietic Stem Cell Transplantation: A 8 Case Report and Literature Review

The clinical characteristics of patients with seizures after allogeneic hematopoietic stem cell transplantation （allo-HSCT） were analyzed. A total of 8 cases of seizures after allo-HSCT were investi- gated. Clinical data of these cases were studied retrospectively. Of 159 cases subjected to allo-HSCT, seizure occurred in 8 cases during 29-760 days after transplantation, median survival time was 46 days, and there were 6 cases of tonic-clonic seizure. The incidence of seizure after matched unrelated HSCT was higher than that after related HSCT （P=-O.O17）. Of 7 cases treated with cyclosporine A （CsA）, 4 cases obtained high blood levels of CsA. In addition, hyponatremia was diagnosed in 5 cases. Abnormal electroencephalogram and brain MRI findings were found in some cases. During 20 days after seizure, 2 cases died due to infection and graft-versus-host disease （GVHD）, respectively. It was suggested that multiple factors are associated with seizures after aUo-HSCT. Rapid identification and correction of the causative factors are very important to prevent permanent central nervous system damage and reduce the mortality.

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.

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.

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.

An addition of medium-dose ATG to conditioning regimens favours the long-term survival of patients with allogeneic hematopoietic stem cell transplantation

Long-term survival of 116 leukemia/MDS patients received allo-SCT conditioned by a regimen with ATG-F or without ATG-F was analysed, together with the impact of ATG-F on the long-term survival, GVHD and disease relapse. Seventy patients received an ATG-F containing conditioning regimen FBCA, and 46 patients received a non-ATG-F FBC regimen. The FBCA regimen was associated with a 5-year survival of 65.4% in the complete HLA-matched group and 39.3% in the HLA-mismatched group. The difference between the two groups was significant (P = 0.012). For the FBC conditioning regimen, the 5-year overall survival of HLA-matched patients and the HLA-mismatched patients was 34.2% and 24.2% respectively (P = 0.216). The incidence of cGVHD was 32.9% and 83.6% in the FBCA and FBC condition regimen group respectively. Only 2.9% of the cases showed extensive cGVHD in the FBCA group while it was 69.4% in the FBC group (P = 0.00). Multivariate analysis indicated that relapse was related to the disease status and HLA typing, but unrelated to the conditioning regimens whether or not ATG-F was used (HR 0.54, P = 0.109). We conclude that the addition of ATG-F to conditioning regimen favours the longterm survival of allo-SCT.