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Type II innate lymphoid cells (ILC2s) maintain homeostasis and barrier integrity in mucosal tissues. In both mice and humans, ILC2s poorly reconstitute after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Determining the mechanisms involved in their impaired reconstitution could improve transplant outcomes. By integrating single-cell chromatin and transcriptomic analyses of transplanted ILC2s, we identify a previously unreported population of converted ILC1-like cells in the mouse small intestine post-transplant. Exposure of ILC2s to proinflammatory cytokines resulted in a mixed ILC1-ILC2 phenotype but was able to convert only a small population of ILC2s to ILC1s, which were found post-transplant. Whereas ILC2s protected against acute graft-versus-host disease (aGVHD) mediated mortality, infusion of proinflammatory cytokine-exposed ILC2s accelerated aGvHD. Interestingly, murine ILC2 reconstitution post-HSCT is decreased in the presence of alloreactive T cells. Finally, peripheral blood cells from human patients with aGvHD have an altered ILC2-associated chromatin landscape compared to transplanted controls. These data demonstrate that following transplantation ILC2s convert to a pro-pathogenic population with an ILC1-like chromatin state and provide insights into the contribution of ILC plasticity to the impaired reconstitution of ILC2 cells, which is one of several potential mechanisms for the poor reconstitution of these important cells after allo-HSCT. Allogeneic hematopoietic stem cell transplantation restores the whole hematopoietic compartment of the recipient, but some cell types, such as Type II innate lymphoid cells (ILC2) are not reconstituted efficiently. Here authors show that ILC2s could be converted to ILC1-like cells in the mouse small intestine post-transplantation, which might contribute to the lower than physiological ILC2 numbers. [ABSTRACT FROM AUTHOR]

Alloreactive donor T cells undergo extensive metabolic reprogramming to become activated and induce graft-versus-host disease (GVHD) upon alloantigen encounter. It is generally thought that glycolysis, which promotes T cell growth and clonal expansion, is employed in this process. However, conflicting data have been reported regarding the requirement of glycolysis to induce T cell-mediated GVHD due to the lack of T cell-specific treatments using glycolysis inhibitors. Importantly, previous studies have not evaluated whether graft-versus-leukemia (GVL) activity is preserved in donor T cells deficient for glycolysis. As a critical component affecting the clinical outcome, it is necessary to assess the anti-tumor activity following treatment with metabolic modulators in preclinical models. In the present study, we utilized T cells selectively deficient for glucose transporter 1 (Glut1T-KO), to examine the role of glycolysis exclusively in alloreactive T cells without off-targeting effects from antigen presenting cells and other cell types that are dependent on glycolysis. We demonstrated that transfer of Glut1T-KO T cells significantly improved acute GVHD outcomes through increased apoptotic rates, impaired expansion, and decreased proinflammatory cytokine production. In addition to impaired GVHD development, donor Glut1T-KO T cells mediated sufficient GVL activity to protect recipients from tumor development. A clinically relevant approach using donor T cells treated with a small molecule inhibitor of glycolysis, 2-Deoxy-D-glucose ex vivo, further demonstrated protection from tumor development. These findings indicate that treatment with glycolysis inhibitors prior to transplantation selectively eliminates alloreactive T cells, but spares non-alloreactive T cells including those that protect against tumor growth. The present study has established a definitive role for glycolysis in acute GVHD and demonstrated that acute GVHD can be selectively prevented through targeting glycolysis. [ABSTRACT FROM AUTHOR]

Allogeneic-HCT (allo-HCT), while potentially curative, can result in significant complications including graft versus host disease (GVHD). Prior studies suggest that metabolic syndrome may be one risk factor for GVHD. We hypothesized that hepatic steatosis on pre-HCT computed tomography (CT) scans may be a marker for development of GVHD and poor outcomes in allo-HCT. In this retrospective study, we reviewed the pre-HCT CT scans and transplant outcome data of patients who underwent allo-HCT at Duke University Medical Center from 2009 to 2017. The presence of steatosis was confirmed using CT attenuation measurements. We then assessed the association between pre-HCT hepatic steatosis and HCT-related outcomes including GVHD. 80 patients who had pre-HCT CT scans were included in the study. Pre-transplant hepatic steatosis was associated with the development of chronic GVHD (OR 4.2, p = 0.02), but was not associated with acute GVHD (OR 1.3, p = 0.7), non-relapse mortality (p = 0.81) or overall survival (p = 0.74). Based on this single center retrospective study, pre-transplant hepatic steatosis is associated with development of chronic GVHD. Further, prospective study with other imaging modalities including non-contrasted CT scans is needed to determine if this association is reproducible. [ABSTRACT FROM AUTHOR]

Data from both animal models and humans have demonstrated that effector memory T cells (TEM) and central memory T cells (TCM) from unprimed donors have decreased ability to induce graft-vs-host disease (GVHD). Allospecific TEM from primed donors do not mediate GVHD. However, the potential of alloreactive TCM to induce GVHD is not clear. In this study, we sought to answer this question using a novel GVHD model induced by T cell receptor (TCR) transgenic OT-II T cells. Separated from OT-II mice immunized with OVA protein 8 weeks earlier, the allospecific CD44high TCM were able to mediate skin graft rejection after transfer to naive mice, yet had dramatically decreased ability to induce GVHD. We also found that these allospecific CD44high TCM persisted in GVHD target organs for more than 30 days post-transplantation, while the expansion of these cells was dramatically decreased during GVHD, suggesting an anergic or exhausted state. These observations provide insights into how allospecific CD4+ TCM respond to alloantigen during GVHD and underscore the fundamental difference of alloresponses mediated by allospecific TCM in graft rejection and GVHD settings. [ABSTRACT FROM AUTHOR]

Graft-versus-host disease (GVHD) after allogeneic stem-cell transplantation causes significant morbidity and mortality. An important site of GVHD is the gastrointestinal (GI) tract because development of acute GI GVHD is prognostic of overall survival. The standard of care to treat acute GI GVHD is systemic corticosteroids and immunosuppressants; however, the use of these therapies can cause life-threatening opportunistic infections. To limit the adverse effects of systemic immunosuppression, the topically active corticosteroid beclometasone dipropionate has been investigated in case studies and in randomized placebo-controlled trials for the treatment of acute GI GVHD. In this review, we appraise these studies with beclometasone dipropionate, and discuss future randomized studies to clarify the role of beclometasone dipropionate for the treatment and prevention of acute GVHD. At present, more data are required before the addition of beclometasone dipropionate to systemic corticosteroids for the treatment of acute GVHD can be considered the standard of care. [ABSTRACT FROM AUTHOR]

The molecular biology and pathophysiology underlying graft-versus-host disease (GvHD) remains an area of intensive research. Understanding normal and abnormal developments of both the innate and adaptive immune systems are beginning to provide understanding of the details of relevant pathways. Recent work in gene-expression profiling suggests a critical next step in identifying broader patterns that will stand up to examination in independent data sets and provide a sturdy basis for targeted therapy and preventive measures against GvHD. [Copyright &y& Elsevier]

Abstract: Haploidentical hematopoietic stem cell transplantation (HSCT) provides an opportunity for patients to benefit from HCT when a human leukocyte antigen (HLA) genotypically matched sibling is not available. Initial results with the use of mismatched allograft has been disappointing due to the high incidence of graft-versus-host disease (GVHD) and infectious complications resulting in an unacceptable treatment-related morbidity and mortality. Recent advances with effective T-cell depletion, the use of ‘megadose’ of stem cells and reduced intensity conditioning has significantly decreased the early transplant related mortality and GvHD, while enabling robust and prompt engraftment, and hence enhancing the therapeutic benefits of haploidentical transplantation. However, the cardinal problems related to delayed immune reconstitution causing posttransplant infectious complications and relapse remain, limiting the efficacy of haploidentical transplant. Preliminary data have demonstrated the great potential in the use of adoptive cellular immunity and selective allodepletion in rapidly reconstituting immunity without GvHD. The encouraging reports from haploidentical transplant using noninherited maternal antigen (NIMA)-mismatched donors or natural killer alloreactive donors may greatly increase the donor availability and open a way to more appropriate donor selection in HLA-haploidentical HSCT. Future challenges remain in determining the safest approach for haploidentical transplant to be performed with minimal risk of GvHD, while preserving effective graft-versus-leukemia activity and promoting prompt immune reconstitution. [Copyright &y& Elsevier]

Summary: Allogeneic transplant offers a curative option for selected hematological malignancies and improved disease free survival in those where cure is not possible. For patients in these categories, Graft-versus-host disease (GVHD) occurs often and is a significant cause of morbidity and mortality following transplantation. Pharmacological immunosuppression has considerable toxicity and controls GVHD in about 75% of transplant recipients when used in combination and continually. Thus, there is the need for viable and non-toxic alternatives for GVHD prevention and this is the impetus for seeking novel non-pharmacological strategies. Most techniques directed to this end are based on various permutations of T-cell depletion. Total T-cell depletion was the first graft engineering strategy employed but while beneficial, it was associated with delay in engraftment and early relapses. Modern depletion and adoptive immunotherapy techniques are directed toward specific subsets of T-cells which include alloreactive, naïve, NK cells, T-helper and cytotoxic T-cells. While large bodies of preclinical evidence attest to the efficacy of currently available non-pharmacological prevention techniques, such is not the case with vigorous clinical trials. Where available, the proven non-pharmacological prevention techniques are yet to be fully interwoven into the patient care arena. Integration of available strategies and continuing research are therefore acutely needed to improve the chronic morbidity and mortality seen with both allogeneic transplant-associated GVHD and the use of pharmaceutical immunosuppressants. [Copyright &y& Elsevier]

Minor histocompatibility antigens (miHA) are responsible for the occurrence of graft-versus-host disease in the setting of a major histocompatibility complex matched sibling allogeneic stem cell transplantation. These miHA are peptide fragments that are associated with major histocompatibility complex class I or class II antigens. Elegant experiments have led to the molecular characterization of these antigens. Efforts to prevent graft-versus-host disease could be targeted through this pathway by matching for these miHA or by preventing antigen recognition. Alternatively, these miHA could be exploited as targets for a more potent graft-versus-malignancy effect. This area of miHA promises to continue to be an exciting area of continued research. [Copyright &y& Elsevier]

Unrelated umbilical cord blood (UCB) transplantation has recently been explored in an increasing number of adult patients. The relative ease of procurement and the lower-than-anticipated risk of severe acute graft-versus-host disease has made UCB transplantation an appealing alternative to bone marrow-derived hematopoietic stem cells. The use of reduced-intensity or nonmyeloablative preparative regimens to allow engraftment of UCB broadens the scope of patients who may benefit from allogeneic immunotherapy, including elderly and medically infirm patients with no matched sibling donor. This review summarizes the available data on the use of UCB as an alternative source of hematopoietic stem cell transplantation in adult patients. [Copyright &y& Elsevier]

Background: Graft-versus-host disease (GVHD) caused by poorly defined minor (i.e., other than HLA) histocompatibility antigens remains a serious problem in recipients of bone marrow transplants. We sought to determine whether the CD31 adhesion molecule is a minor alloantigen. Methods: We directly sequenced samples of complementary DNA (cDNA) encoding CD31 molecules from 21 unrelated normal subjects. Sequence-specific primers were then designed to amplify alleles by the polymerase chain reaction, thereby permitting CD31 typing of genomic DNA from additional normal subjects. To assess the relevance of CD31 matching to bone marrow transplantation, we performed CD31 typing of 46 recipients of bone marrow (32 without GVHD and 14 with severe [grade III or IV] acute GVHD) and their HLA-identical sibling donors. The immunoreactivity of CD31 phenotypes with anti-CD31 monoclonal antibodies was compared by flow cytometry. Results: Direct sequencing of cDNA for CD31 from the 21 normal subjects identified a single polymorphism, CTG→GTG (Leu→Val), at codon 125; we designated the resulting alleles CD31.L and CD31.V, respectively. The CD31 genotypes of these and 142 other unrelated subjects were of the expected frequencies. Among the transplant recipients, 71 percent of those with acute GVHD had CD31 genotypes that were not identical to the donor's genotype, as compared with 22 percent of the recipients without GVHD (P = 0.004). The binding of anti-CD31 monoclonal antibodies as measured by fluorescence-activated cell sorting correlated with the CD31 types of homozygous cell lines. Conclusions: The adhesion molecule CD31 is polymorphic. When donor and recipient genotypes are not identical, the risk of GVHD increases. Prospective CD31 typing may reduce the risk of acute GVHD. (N Engl J Med 1996;334:286-91.) [ABSTRACT FROM AUTHOR]

Background: Acute graft-versus-host disease (GVHD) following allogeneic bone marrow transplantation remains a serious problem. In a clinical trial, we tested the combination of cyclosporine and prednisone with and without methotrexate for the prevention of GVHD. Methods: One hundred fifty patients with either acute leukemia in first complete remission, chronic myelogenous leukemia in first chronic phase, or lymphoblastic lymphoma in first complete remission were enrolled in the study. All the patients were given fractionated total-body irradiation (1320 cGy) and etoposide (60 mg per kilogram of body weight) in preparation for transplantation, and received bone marrow from genotypically histocompatible donors. To prevent GVHD, they were randomly assigned to prophylactic treatment with either cyclosporine, methotrexate, and prednisone or cyclosporine and prednisone without methotrexate. All the patients received standardized supportive care after transplantation, including intravenous gamma globulin. Results: Patients receiving cyclosporine, methotrexate, and prednisone had a significantly lower incidence of acute GVHD of grades II to IV (9 percent) than those receiving cyclosporine and prednisone (23 percent, P = 0.02). Multivariate regression analysis demonstrated that an increased risk of acute GVHD was associated with an elevated serum creatinine concentration (P = 0.006) and treatment with cyclosporine and prednisone alone (P = 0.02). The lower incidence of acute GVHD was not associated with a higher rate of relapse of leukemia or lymphoma. There was no significant difference in disease-free survival at three years between the two treatment groups (64 percent with the three-drug regimen vs. 59 percent with the two-drug regimen, P = 0.57). Conclusions: The combination of cyclosporine, methotrexate, and prednisone was more effective in preventing acute GVHD of grades II to IV than was the combination of cyclosporine and prednisone without methotrexate. (N Engl J Med 1993;329:1225-30.) [ABSTRACT FROM AUTHOR]

Abstract: Haploidentical hematopoietic stem cell transplantation (HSCT) provides an opportunity for nearly all patients to benefit from HSCT when a human leukocyte antigen (HLA) genotypically matched sibling is not available. Initial results with the use of mismatched allografts led to limited enthusiasm because of graft-versus-host disease (GVHD) and infectious complications, resulting in an unacceptable treatment-related morbidity and mortality. Recent advances with effective T cell depletion, the use of a “megadose” of stem cells, earlier detection of severe infections, combined with better antimicrobial therapy and reduced-intensity conditioning (RIC) has significantly decreased the early transplant-related mortality and GVHD, whereas enabling prompt engraftment, hence advancing the therapeutic benefit of haploidentical transplantation. However, the cardinal problems related to delayed immune reconstitution allowing posttransplant infectious complications and relapse remain, limiting the efficacy of haploidentical HSCT. Preliminary data has demonstrated the potential for use of adoptive cellular immunity and selective allodepletion in rapidly reconstituting immunity without GVHD. The encouraging reports from haploidentical transplant using noninherited maternal antigen (NIMA)-mismatched or natural killer (NK) alloreactive donors may greatly increase the donor availability and open the way to more appropriate donor selection in HLA-haploidentical HSCT. Future challenges remain in determining the safest approach for haploidentical transplant to be performed with minimal risk of GVHD, whereas preserving effective graft-versus-leukemia activity and promoting prompt immune reconstitution. [Copyright &y& Elsevier]

Gastrointestinal (GI) complications including graft-versus-host disease (GVHD) are a major cause of morbidity and mortality in allogenic stem transplant recipients. Although several studies have previously looked into the acute GI complications, fewer smaller studies have reported late complications. In this large study we focus on the late (100 days post-transplant) GI complications in allogenic stem transplant recipients. In this single-center, retrospective study of all adult allogenic stem cell transplant recipients who had their transplant at Duke University over a 6-year period, 479 patients underwent allogenic stem cell transplant, of whom 392 recipients survived for at least 100 days post-transplant. Late GI symptoms were noted in 71 patients, prompting endoscopic evaluation. The primary endpoint of our study was the diagnosis of GI-GVHD based on endoscopic findings, whereas overall survival and nonrelapse mortality were the secondary endpoints. Of the 71 patients who underwent endoscopy, 45 (63%) had GI-GVHD. Of these 45 patients, 39 (87%) had late acute GVHD, 1 (2%) had chronic GVHD, and 5 patients (11%) had overlap disease. Of the patients who did not have GVHD, the symptoms were mostly related to infectious and inflammatory causes. Less common causes included drug toxicity, food intolerance, disease relapse, and motility issues. In a multivariate analysis the factors most indicative of GI-GVHD were histologic findings of apoptosis on the tissue specimen (odds ratio, 2.35; 95% confidence interval, 1.18 to 4.70; P  = .015) and clinical findings of diarrhea (odds ratio, 5.43; 95% confidence interval, 1.25 to 23.54; P  = .024). The median survival time from the first endoscopy was 8.5 months. The incidence of nonrelapse mortality at 6 months was 31% in patients with GI-GVHD and 19% in patients without GI-GVHD ( P  = .42). All patients with GI-GVHD were on steroid therapy, and 31% of them received total parenteral nutrition. In our population close to one-fifth of allogenic transplant recipients experienced late GI complications, warranting endoscopic evaluation. Most of these patients were found to have GI-GVHD that had a high incidence of nonrelapse mortality at 6 months and close to one-third of these patients needed total parenteral nutrition. [ABSTRACT FROM AUTHOR]

B-cell receptor (BCR)-activated B cells contribute to pathogenesis in chronic graftversus- host disease (cGVHD), a condition manifested by both B-cell autoreactivity and immune deficiency. We hypothesized that constitutive BCR activation precluded functional B-cell maturation in cGVHD. To address this, we examined BCR-NOTCH2 synergy because NOTCH has been shown to increase BCR responsiveness in normal mouse B cells. We conducted ex vivo activation and signaling assays of 30 primary samples from hematopoietic stem cell transplantation patients with and without cGVHD. Consistent with a molecular link between path ways, we found that BCR-NOTCHactivation significantly increased the proximal BCR adapter protein BLNK. BCR-NOTCH activation also enabled persistent NOTCH2 surface expression, suggesting a positive feedback loop. Specific NOTCH2 blockade eliminated NOTCH-BCR activation and significantly altered NOTCH downstream targets and B-cell maturation/effector molecules. Examination of the molecular underpinnings of this "NOTCH2-BCR axis" in cGVHD revealed imbalanced expression of the transcription factors IRF4 and IRF8, each critical to B-cell differentiation and fate. All-trans retinoic acid (ATRA) increased IRF4 expression, restored the IRF4-to-IRF8 ratio, abrogated BCR-NOTCH hyperactivation, and reduced NOTCH2 expression in cGVHD B cells without compromising viability. ATRA-treated cGVHD B cells had elevated TLR9 and PAX5, but not BLIMP1 (a gene-expression pattern associated with mature follicular B cells) and also attained increased cytosine guanine dinucleotide responsiveness. Together, we reveal a mechanistic link between NOTCH2 activation and robust BCR responses to otherwise suboptimal amounts of surrogate antigen. Our findings suggest that peripheral B cells in cGVHD patients can be pharmacologically directed from hyperactivation toward maturity. [ABSTRACT FROM AUTHOR]

Delayed hematopoietic recovery contributes to increased infection risk following umbilical cord blood (UCB) transplantation. In a Phase 1 study, adult recipients of UCB stem cells cultured ex vivo for 3 weeks with nicotinamide (NiCord) had earlier median neutrophil recovery compared with historical controls. To evaluate the impact of faster neutrophil recovery on clinically relevant early outcomes, we reviewed infection episodes and hospitalization during the first 100 days in an enlarged cohort of 18 NiCord recipients compared with 86 standard UCB recipients at our institution. The median time to neutrophil engraftment was shorter in NiCord recipients compared with standard UCB recipients (12.5 days versus 26 days; P  < .001). Compared with standard UCB recipients, NiCord recipients had a significantly reduced risk for total infection (RR, 0.69; P  = .01), grade 2-3 (moderate to severe) infection (RR, 0.36; P  < .001), bacterial infection (RR, 0.39; P  = .003), and grade 2-3 bacterial infection (RR, 0.21; P  = .003) by Poisson regression analysis; this effect persisted after adjustment for age, disease stage, and grade II-IV acute GVHD. NiCord recipients also had significantly more time out of the hospital in the first 100 days post-transplantation after adjustment for age and Karnofsky Performance Status (69.9 days versus 49.7 days; P  = .005). Overall, transplantation of NiCord was associated with faster neutrophil engraftment, fewer total and bacterial infections, and shorter hospitalization in the first 100 days compared with standard UCB transplantation. In conclusion, rapid hematopoietic recovery from an ex vivo expanded UCB transplantation approach is associated with early clinical benefit. [ABSTRACT FROM AUTHOR]

Although B cells have emerged as important contributors to chronic graft-versus-host- disease (cGVHD) pathogenesis, the mechanisms responsible for their sustained activation remain unknown. We previously showed that patients with cGVHD have significantly increased B cell-activating factor (BAFF) levels and that their B cells are activated and resistant to apoptosis. Exogenous BAFF confers a state of immediate responsiveness to antigen stimulation in normal murine B cells. To address this in cGVHD, we studied B-cell receptor (BCR) responsiveness in 48 patients who were >1 year out from allogeneic hematopoletic stem cell transplantation (HSCT). We found that B cells from cGVHD patients had significantly increased proliferative responses to BCR stimulation along with elevated basal levels of the proximal BCR signaling components 3 cell linker protein (BLNK) and Syk. After initiation of BCR signaling, cGVHD B cells exhibited increased BLNK and Syk phosphorylation compared with B cells from patients without cGVHD. Blocking Syk kinase activity prevented relative post-HSCT BCR hyper-responsiveness of cGVHD B cells. These data suggest that a lowered BCR signaling threshold in cGVHD associates with increased B-cell proliferation and activation in responseto antigen. We reveal a mechanism underpinning aberrant B-cell activation in cGVHD and suggest that therapeutic inhibition of the involved kinases may benefit these patients. [ABSTRACT FROM AUTHOR]

Abstract: We present a comparative study on 124 patients with hematologic malignancies who had undergone reduced-intensity conditioning and then received a transplant from an HLA-matched related (MRD), an HLA-matched unrelated (MUD), or an HLA-haploidentical related (HAPLO) donor. The conditioning regimen, which consisted of fludarabine, melphalan or busulfan, and alemtuzumab was administered to patients with lymphoid (n = 62) or myeloid disease (n = 62). Mycophenolate mofetil was used as prophylaxis for graft-versus-host disease (GVHD), and 38, 58, and 33 patients received transplants from MRD, MUD, and HAPLO donors, respectively. Only 2 patients experienced primary graft failure (GF) after melphalan-based regimen, whereas 8 of the 17 patients who received a transplant from HAPLO donors experienced a primary GF after busulfan-based regimen. The cumulative incidence of grade III to IV acute GVHD in engrafted patients who had received transplants from MRD, MUD, or HAPLO donors was 3%, 11%, and 27%, respectively, and the 2-year overall survival (OS) rates were 51%, 22%, and 23%, respectively. According to multivariate analysis, transplantation from either MUD or HAPLO donors compared with MRD were adverse factors that affected the OS (P = .006 and P = .002, respectively). In conclusion, the reduced-intensity regimen that included fludarabine, busulfan, or melphalan and alemtuzumab using only mycophenolate mofetil as the GVHD prophylaxis conferred favorable outcomes in the MRD group but lower survival rates in the MUD and HAPLO groups. The busulfan-based regimen led to a high incidence of GF in the HAPLO group, suggesting the need for modification or intensification of immunosuppression. [Copyright &y& Elsevier]

Acute graft-versus-host disease (aGVHD) is the leading cause of morbidity and mortality after allogeneic hematopoietic cell transplantation (HCT). Approximately 35% to 50% of HCT recipients develop aGVHD; however, there are no validated diagnostic and predictive blood biomarkers for aGVHD in clinical use. Here, we show that plasma samples from aGVHD patients have a distinct microRNA (miRNA) expression profile. We found that 6 miRNAs (miR-423, miR-199a-3p, miR-93", miR-377, miR-155, and miR-30a) were significantly upregulated in the plasma of aGVHD patients (n = 116) when compared with - non-GVHD patients (n = 52) in training and validation phases. We have developed a model including 4 miRNAs (miR-423, miR-199a-3p, miR-93", and miR-377) that can predict the probability of aGVHD with an area under the curve of 0.80. Moreover, these elevated miRNAs were detected before the onset of aGVHD (median = 16 days before diagnosis). In addition, the levels of these miRNAs were positively associated with aGVHD severity, and high expression of the miRNA panel was associated with poor overall survival. Furthermore, the miRNA signature for aGVHD was not detected in the plasma of lung transplant or nontransplant sepsis patients. Our results have identified a specific plasma miRNA signature that may serve as an independent biomarker for the prediction, diagnosis, and prognosis of aGVHD. [ABSTRACT FROM AUTHOR]

Graft-versus-host disease (GVHD) re-mains the most common cause of nonrelapse-related morbidity and mortal-ity after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Although T-cell depletion and intensive immunosup-pression are effective in the control of GVHD, they are often associated with higher rates of infection and tumor recur-rence. In this study, we showed that hepa-ran sulfate (HS), an extracellular matrix component, can activate Toll-like recep-tor 4 on dendritic cells in vitro, leading to the enhancement of dendritic cell matura-tion and alloreactlve T-cell responses. We further demonstrated in vivo that serum HS levels were acutely elevated at the onset of clinical GVHD in mice after allo-HSCT. Treatment with the serine protease inhibitor «1-antitrypsin decreased serum levels of HS, leading to a reduction in alloreactive T-cell responses and GVHD severity. Conversely, an HS mimetic that increased serum HS levels accelerated GVHD. In addition, in patients undergoing allo-HSCT for hematologic malignancies, serum HS levels were elevated and corre-lated with the severity of GVHD. These results identify a critical role for HS in promoting acute GVHD after allo-HSCT, and they suggest that modulation of HS release may have therapeutic potential for the control of clinical GVHD. [ABSTRACT FROM AUTHOR]

We studied whether allospecific CD4+ effector memory T cells (TEM) could induce graft-versus-host disease (GVHD) using a novel GVHD model induced solely by CD4+ T cell receptor transgenic TEa cells. Allospecific TEM generated in a lymphopenic host bore a typical memory phenotype. Moreover, these cells were able to elicit a faster and more effective proliferative response on challenge with alloantigen in vitro and to mediate “second-set” skin graft rejection in vivo. However, these allospecific TEM were unable to induce GVHD. Allospecific TEM recipients became tolerant to alloantigen as a result of clonal deletion. Even though allospecific TEM were able to respond to alloantigen initially, the expansion of these cells and inflammatory cytokine production during GVHD were dramatically decreased. The inability of allospecific TEM to sustain the alloresponse may be a result of enhanced activation-induced cell death. These observations provide insight into how allospecific CD4+ TEM respond to alloantigen during GVHD and underscore the fundamental differences in alloresponses mediated by allospecific TEM in graft rejection and GVHD settings. [Copyright &y& Elsevier]

Risk factors for acute GVHD (AGVHD), overall survival, and transplant-related mortality were evaluated in adults receiving allogeneic hematopoietic cell transplants (1999-2005) from HLA-identical sibling donors (SDs; n = 3191) or unrelated donors (URDs; n = 2370) and reported to the Center for International Blood and Marrow Transplant Research, Minneapolis, MN. To understand the impact of transplant regimen on AGVHD risk, 6 treatment categories were evaluated: (1) myeloablative conditioning (MA) with total body irradiation (TBI) + PBSCs, (2) MA + TBI + BM, (3) MA + nonTBI + PBSCs, (4) MA + nonTBI + BM, (5) reduced intensity conditioning (RIC) + PBSCs, and (6) RIC + BM. The cumulative incidences of grades B-D AGVHD were 39% (95% confidence interval [CI], 37%-41%) in the SD cohort and 59% (95% CI, 57%-61%) in the URD cohort. Patients receiving SD transplants with MA + nonTBI + BM and RIC + PBSCs had significantly lower risks of grades B-D AGVHD than patients in other treatment categories. Those receiving URD transplants with MA + TBI + BM, MA + nonTBI + BM, RIC + BM, or RIC + PBSCs had lower risks of grades B-D AGVHD than those in other treatment categories. The 5-year probabilities of survival were 46% (95% CI, 44%-49%) with SD transplants and 33% (95% CI, 31%-35%) with URD transplants. Conditioning intensity, TBI and graft source have a combined effect on risk of AGVHD that must be considered in deciding on a treatment strategy for individual patients. [ABSTRACT FROM AUTHOR]

Infusing natural killer (NK) cells following transplantation may allow less infections and relapse with little risk of acute graft-versus-host disease (aGVHD). We delivered 51 total NK cell-enriched donor lymphocyte infusions (DLIs) to 30 patients following a 3-6/6 HLA matched T cell-depleted nonmyeloablative allogeneic transplant. The primary endpoint of this study was feasibility and safety. Eight weeks following transplantation, donor NK cell-enriched DLIs were processed using a CD56+ selecting column with up to 3 fresh infusions allowed. Toxicity, relapse, and survival were monitored. T cell phenotype, NK cell functional recovery, and KIR typing were assessed for association with outcomes. Fourteen matched and 16 mismatched transplanted patients received a total of 51 NK cell-enriched DLIs. Selection resulted in 96% (standard deviation [SD] 8%) purity and 83% (SD 21%) yield in the matched setting and 97% (SD 3%) purity and 77% (SD 24%) yield in the mismatched setting. The median number of CD3− CD56+ NK cells infused was 10.6 (SD 7.91) × 106 cells/kg and 9.21 (SD 5.6) × 106 cells/kg, respectively. The median number of contaminating CD3+CD56− T cells infused was .53 (1.1) × 106 and .27 (.78) × 106 in the matched and mismatched setting, respectively. Only 1 patient each in the matched (n = 14) or mismatched (n = 16) setting experienced severe aGVHD with little other toxicity attributable to the infusions. Long-term responders with multiple NK cell-enriched infusions and improved T cell phenotypic recovery had improved duration of responses (p = .0045) and overall survival (OS) (P = .0058). A 1-step, high-yield process is feasible, and results in high doses of NK cells infused with little toxicity. NK cell-enriched DLIs result in improved immune recovery and outcomes for some. Future studies must assess whether the improved outcomes are the direct result of the high doses and improved NK cell function or other aspects of immune recovery. [Copyright &y& Elsevier]

Currently, no agents are approved by the United States Food and Drug Administration (FDA) for either prevention or treatment of acute graft-versus-host disease (aGVHD). Formal precedents establishing a comparative basis for assessing the efficacy and safety of new investigational agents are still lacking. As a step toward addressing this problem, a panel of experts met on 2 occasions to reach consensus on recommendations for terminology describing a clinically meaningful primary endpoint in studies assessing treatment for aGVHD. The panel recommended terminology for “very good partial response” (VGPR) that includes both diagnostic and functional criteria. The central hypothesis leading to this proposal is that the potential harm of giving more treatment than needed to produce or maintain complete response exceeds the harm of slight undertreatment that may be associated with less than complete response. VGPR clearly cannot be used as the sole outcome measure in GVHD treatment trials, and must be considered in the context of survival and safety. The proposed use of VGPR as the primary endpoint in GVHD treatment trials will remain provisional until its use has been validated through experience. [Copyright &y& Elsevier]

Gastrointestinal (GI) toxicity and acute graft versus host disease (GVHD) are significant morbidities associated with allogeneic hematopoietic stem cell transplantation (HSCT). The somatostatin analogue Octreotide ameliorates mucosal injury from radiation damage in pre-clinical mouse models. We hypothesized that administration of the longer-acting synthetic somatostatin analogue, Pasireotide, in the peri-transplant period would decrease acute GI toxicity and acute GVHD related to allogeneic HSCT. Adult patients who underwent matched allogeneic HSCT with myeloablative conditioning were eligible for this study. Exclusion criteria included severe cardiac and endocrine abnormalities. Pasireotide was administered at 0.9mg twice daily from the day before conditioning began to day +4. The co-primary endpoints were 1) Acute GI toxicity, defined as GI toxicity occurring from the day prior to conditioning to day +30, and 2) Acute GVHD. Results were compared with 50 historical controls matched by Transplant diagnosis, Donor, Graft, GVHD prophylaxis, and Conditioning regimen. 36 patients were consented for the study, 25 patients received the study drug (5 screen failures, 1 insurance denial, 3 withdrew consent, 1 switched trials, 1 enrolled at an alternate center without available follow-up). There was no difference in Acute GI toxicity, which occurred in all patients in both the Pasireotide and Control groups. Grade 3 or 4 GI toxicity was similar, occurring in 20 patients (80%) in the Pasireotide group and 35 patients (70%) in the Control group. Specific GI toxicities varied in incidence between the Control and Pasireotide study groups (Figure 1), most notable for numerically higher rates of the expected toxicities abdominal pain, bloating, and vomiting in the Pasireotide group. Other common toxicities that occurred in the Pasireotide and Control groups are listed in Figure 1. There was no significant difference in incidence of overall Acute GVHD or Acute GI GVHD (Figure 2). The subset of patients who received Total Body Irradiation (TBI) conditioning had numerically lower Acute GVHD in the Pasireotide group (5/9, 55%) compared to the Control group (16/20, 80%), however this was not statistically significant (Fisher's Exact Test, p=0.21); these patients also had a lower rate of combined upper and lower GI GVHD (3/9, 33% in the Pasireotide group versus 11/20, 55% in the Control group), though this was not statistically significant (Fisher's Exact Test, p=0.43). In this Phase 2 study, the somatostatin analogue Pasireotide did not decrease GI toxicity in allogeneic HSCT; however, in the subset of patients who received TBI conditioning, there was a numerically (but not statistically) significant decrease in overall and GI Acute GVHD. Further study in a larger cohort of patients undergoing TBI conditioning is warranted. [ABSTRACT FROM AUTHOR]

Abstract: T-cell receptor variable β chain (TCRBV) repertoire spectratyping involves the estimation of CDR3 length distributions for monitoring T-cell receptor diversity and has proven useful for analyses of immune reconstitution and T-cell clonal expansions in graft-versus-host disease (GVHD) and graft-versus-leukemia after allogeneic stem cell transplantation. We performed a longitudinal spectratype analysis of 23 TCRBV families in 28 patients who underwent allogeneic T cell–depleted peripheral blood stem cell transplantation. Sixteen patients subsequently developed acute GVHD. We recently developed statistical methods that bring increased power and flexibility to spectratype analysis and allow us to analyze TCRBV repertoire development under appropriately complex statistical models. Applying these methods, we found that patients with acute GVHD demonstrated TCRBV repertoire development statistically distinct from that repertoire development in patients without GVHD. Specifically, GVHD patients showed spectratypes indicative of lower diversity and greater deviation from the spectratypes expected in healthy individuals at intermediate times. Most individual TCRBV subfamilies had spectratypes statistically distinguishable between GVHD and non-GVHD patients at 6 months after transplantation. These results suggest that the T-cell receptor repertoire perturbations associated with acute GVHD are widely spread throughout the TCRBV families. [Copyright &y& Elsevier]

Background Several professional societies have established nutrition guidelines for patients undergoing HSCT. We surveyed HSCT programs to understand how these compare with clinical practice. Methods Qualitative surveys were emailed to HSCT dietitians. Surveys addressed malnutrition screening; dietary recommendations including nutrition support, graft-versus-host disease (GVHD), immune enhancing nutrients, and prebiotics/probiotics; and nutrition-related preventive care screening. Results Twenty adult programs (19 United States (US), 1 Australia) and 3 pediatric programs (3 US) responded. Annual volume across the 22 US programs was 5405 patients, representing 25% of all transplants in the US. Nineteen programs (83%) follow guidelines for nutrition screening and fourteen for nutrition therapy in the inpatient setting (Table 1); six (26%) follow guidelines for screening and therapy in the outpatient setting. All programs adhere to food safety recommendations and 5 (22%) have additional institutional precautions. However, only 2 programs (9%) report frequent adherence to guidelines for use of enteral nutrition. While there are no guidelines for GVHD diet and uncertainty over alternative nutrition practices, 8 programs (35%) follow a stepwise GVHD diet; 4 (17%) allow immunonutrition supplements; 2 (9%) allow prebiotics, and 7 (30%) allow probiotics after the resolution of neutropenia. With regard to adherence to preventive screening recommendations, only 4 programs (17%) screen for diabetes, 6 (26%) screen for hyperlipidemia, and none screen for abdominal obesity. There are no guidelines for vitamin D deficiency screening, but 10 programs (43%) screen for this. Discussion Wide variations in nutrition practices exist across HSCT programs. Similarly, with the exception of food safety recommendations, there are also wide variations in adherence to established nutrition guidelines. The use of enteral nutrition and preventive screening is particularly varied. Efforts are needed to understand barriers to guideline implementation and their correlation to patient outcomes. Further research is needed regarding new interventions such as immunonutrition, prebiotics, and probiotics. [ABSTRACT FROM AUTHOR]