Corticosteroids impair epithelial regeneration in immune-mediated intestinal damage.

Corticosteroid treatment (CST) failure is associated with poor outcomes for patients with gastrointestinal (GI) graft-versus-host disease (GVHD). CST is intended to target the immune system, but the glucocorticoid receptor (GR) is widely expressed, including within the intestines, where its effects are poorly understood. Here, we report that corticosteroids (CS) directly targeted intestinal epithelium, potentially worsening immune-mediated GI damage. CS administered to mice in vivo and intestinal organoid cultures ex vivo reduced epithelial proliferation. Following irradiation, immediate CST mitigated GI damage but delayed treatment attenuated regeneration and exacerbated damage. In a murine steroid-refractory (SR) GVHD model, CST impaired epithelial regeneration, worsened crypt loss, and reduced intestinal stem cell (ISC) frequencies. CST also exacerbated immune-mediated damage in organoid cultures with SR, GR-deficient T cells or IFN-γ. These findings correlated with CS-dependent changes in apoptosis-related gene expression and STAT3-related epithelial proliferation. Conversely, IL-22 administration enhanced STAT3 activity and overcame CS-mediated attenuation of regeneration, reducing crypt loss and promoting ISC expansion in steroid-treated mice with GVHD. Therefore, CST has the potential to exacerbate GI damage if it fails to control the damage-inducing immune response, but this risk may be countered by strategies augmenting epithelial regeneration, thus providing a rationale for clinical approaches combining such tissue-targeted therapies with immunosuppression.

A tissue-intrinsic IL-33/EGF circuit promotes epithelial regeneration after intestinal injury.

Intestinal stem cells (ISCs) maintain the epithelial lining of the intestines, but mechanisms regulating ISCs and their niche after damage remain poorly understood. Utilizing radiation injury to model intestinal pathology, we report here that the Interleukin-33 (IL-33)/ST2 axis, an immunomodulatory pathway monitored clinically as an intestinal injury biomarker, regulates intrinsic epithelial regeneration by inducing production of epidermal growth factor (EGF). Three-dimensional imaging and lineage-specific RiboTag induction within the stem cell compartment indicated that ISCs expressed IL-33 in response to radiation injury. Neighboring Paneth cells responded to IL-33 by augmenting production of EGF, which promoted ISC recovery and epithelial regeneration. These findings reveal an unknown pathway of niche regulation and crypt regeneration whereby the niche responds dynamically upon injury and the stem cells orchestrate regeneration by regulating their niche. This regenerative circuit also highlights the breadth of IL-33 activity beyond immunomodulation and the therapeutic potential of EGF administration for treatment of intestinal injury.

Prognostic value of pre-transplantation total metabolic tumor volume on 18fluoro-2-deoxy-D-glucose positron emission tomography-computed tomography in relapsed and refractory aggressive lymphoma.

Relapsed and refractory aggressive lymphoma have a poor prognosis. High-dose chemotherapy followed by autologous hematopoietic stem cell transplantation (auto-HSCT) is effective in chemosensitive patients. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is among the few options for non-chemosensitive patients. 18Fluoro-2-deoxy-D-glucose positron emission tomography-computed tomography (18FDG-PET/CT) is the standard tool for evaluating response to chemotherapy and residual tumor volume. However, accurate assessment of residual tumor volume is not currently being achieved in clinical practice, and its value in prognostic and therapeutic stratification remains unclear. To answer this question, we investigated the efficacy of quantitative indicators, including total metabolic tumor volume (TMTV), in predicting prognosis after auto-HSCT and allo-HSCT. We retrospectively analyzed 39 patients who received auto-HSCT and 28 who received allo-HSCT. In the auto-HSCT group, patients with a higher TMTV had a poor prognosis due to greater risk of relapse. In the allo-HSCT group, patients with a higher TMTV had a lower progression-free survival rate and a significantly higher relapse rate. Neither Deauville score nor other clinical parameters were associated with prognosis in either group. Therefore, pre-transplant TMTV on PET is effective for prognostic prediction and therapeutic decision-making for relapsed or refractory aggressive lymphoma.

Incidence of refractory cytomegalovirus infection after allogeneic hematopoietic stem cell transplantation.

Post-transplant cytomegalovirus (CMV) disease can be almost completely avoided by current infection control procedures. However, CMV reactivation occurs in more than half of patients, and some patients can develop clinically resistant CMV infections. Whether resistance is due to the host's immune status or a viral resistance mutation is challenging to confirm. Therefore, a prospective observational analysis of refractory CMV infection was conducted in 199 consecutive patients who received allogeneic hematopoietic stem cell transplantation at a single institution. Among them, 143 (72%) patients received anti-CMV drugs due to CMV reactivation, and only 17 (8.5%) exhibited refractory CMV infection. These patients had clinically refractory infection. However, viral genome analysis revealed that only one patient exhibited a mutation associated with the anti-CMV drug resistance. Clinical resistance was mainly correlated with host immune factors, and the incidence of resistance caused by gene mutations was low at the early stage after a transplantation.

T Cell Recruitment to the Intestinal Stem Cell Compartment Drives Immune-Mediated Intestinal Damage after Allogeneic Transplantation.

The key sites within the gastrointestinal (GI) tract where T cells mediate effector responses and the impact of these responses on intestinal stem cells (ISCs) remain unclear. Using experimental bone marrow transplantation to model immune-mediated GI damage and 3D imaging to analyze T cell localization, we found that the ISC compartment is the primary intestinal site targeted by T cells after transplantation. Recruitment to the crypt base region resulted in direct T cell engagement with the stem cell compartment and loss of crypt base columnar ISCs, which expressed both MHC classes I and II. Vasculature expressing the adhesion molecule MAdCAM-1 clustered near the crypt base, preferentially regulating crypt compartment invasion and ISC reduction without affecting T cell migration to villi. These findings indicate that allogeneic T cells rapidly access the stem cell niche after transplantation, and this targeted recruitment to the stem cell compartment results in ISC loss during immune-mediated GI damage.

Comparison of cyclosporine and tacrolimus combined with mycophenolate mofetil in prophylaxis for graft-versus-host disease after reduced-intensity umbilical cord blood transplantation.

Umbilical cord blood transplantation with a reduced-intensity conditioning regimen (RIC-UCBT) is used increasingly in patients who have comorbid organ functions and lack human leukocyte antigen-identical donors. We compared the outcomes in 35 patients who received mycophenolate mofetil plus cyclosporine (MMF/CSP, n = 17) or MMF plus tacrolimus (MMF/TAC, n = 18) for graft-versus-host disease (GVHD) prophylaxis after RIC-UCBT. Cumulative incidence of neutrophil engraftment was 94 and 89 % in MMF/CSP and MMF/TAC groups, respectively (p = 0.34). The incidence of pre-engraftment immune reaction did not differ between the MMF/CSP (41 %) and MMF/TAC (39 %, p = 1.00) groups; however, patients in the MMF/TAC group tended to have a lower incidence of grade II-IV acute GVHD than those in MMF/CSP group (28 vs 53 %, p = 0.11). Overall survival (OS) at 1 year was 43 and 60 % in MMF/CSP and MMF/TAC groups, respectively (p = 0.39). Progression-free survival, non-relapse mortality, and relapse rate were comparable between the two groups (p = 0.76, 0.59, and 0.88, respectively). In multivariate analyses, MMF/TAC GVHD prophylaxis was closely associated with improved OS, but not with incidence of engraftment and acute GVHD. These results suggest that more intensive GVHD prophylaxis with MMF/TAC decreased acute GVHD without affecting other clinical outcomes, resulting in improved OS after RIC-UCBT.

Ascites Retention during Mogamulizumab Treatment in a Patient with Adult T-cell Leukemia/lymphoma.

A 74-year-old woman with refractory adult T-cell leukemia/lymphoma (ATLL) received three courses of mogamulizumab. Despite obtaining complete remission, she thereafter presented with progressive ascites. An analysis of the ascites and laboratory tests revealed no evidence of ATLL invasion, infectious disease, or liver cirrhosis. The mogamulizumab concentrations were maintained in the ascites at approximately 10-15% of that in the plasma. Mogamulizumab was considered to be a plausible pathogenesis of her ascites. To the best of our knowledge, this is the first report suggesting mogamulizumab-induced ascites.

Mogamulizumab Treatment Prior to Allogeneic Hematopoietic Stem Cell Transplantation Induces Severe Acute Graft-versus-Host Disease.

Mogamulizumab (MOG), a humanized anti-CC chemokine receptor 4 (CCR4) monoclonal antibody, has recently played an important role in the treatment of adult T cell leukemia/lymphoma (ATLL). Because CCR4 is expressed on normal regulatory T cells as well as on ATLL cells, MOG may accelerate graft-versus-host disease (GVHD) by eradicating regulatory T cells in patients with allogeneic hematopoietic stem cell transplantation (allo-HSCT). However, there is limited information about its safety and efficacy in patients treated with MOG before allo-HSCT. In the present study, 25 patients with ATLL were treated with MOG before allo-HSCT, after which 18 patients (72%) achieved remission. The overall survival and progression-free survival at 1 year post-transplantation were 20.2% (95% CI, 6.0% to 40.3%) and 15.0% (95% CI, 4.3% to 32.0%), respectively. The cumulative incidence of acute GVHD was 64.0% (95% CI, 40.7% to 80.1%) for grade II-IV and 34.7% (95% CI, 15.8% to 54.4%) for grade III-IV. The cumulative incidence of transplantation-related mortality (TRM) was 49.0% (95% CI, 27.0% to 67.8%). Six of 7 patients with acute GVHD grade III-IV died from GVHD, which was the leading cause of death. In particular, a shorter interval from the last administration of MOG to allo-HSCT was associated with more severe GVHD. MOG use before allo-HSCT may decrease the ATLL burden; however, it is associated with an increase in TRM due to severe GVHD. Because MOG is a potent anti-ATLL agent, new treatment protocols should be developed to integrate MOG at suitable doses and timing of administration to minimize unwanted GVHD development.

Cord Blood Transplantation Following Reduced-intensity Conditioning for Adult-onset Inherited Hemophagocytic Lymphohistiocytosis.

Inherited hemophagocytic lymphohistiocytosis (HLH) is a genetic anomaly disorder in which abnormally activated cytotoxic T lymphocytes cannot induce the apoptosis of target cells and antigen-presenting cells, leading to hemophagocytosis, pancytopenia, and a variety of symptoms such as a high fever. The present patient with adult-onset HLH developed refractory disease despite receiving immunosuppressive treatments. He underwent a reduced-intensity conditioning (RIC) regimen that comprised antithymocyte globulin (ATG) followed by cord blood transplantation (RIC-CBT). He achieved and maintained a complete donor type. The incorporation of ATG into RIC-CBT may prevent graft failure and control hemophagocytosis, however, further efforts are necessary to reduce infectious complications.

Interleukin-22 promotes intestinal-stem-cell-mediated epithelial regeneration.

Epithelial regeneration is critical for barrier maintenance and organ function after intestinal injury. The intestinal stem cell (ISC) niche provides Wnt, Notch and epidermal growth factor (EGF) signals supporting Lgr5(+) crypt base columnar ISCs for normal epithelial maintenance. However, little is known about the regulation of the ISC compartment after tissue damage. Using ex vivo organoid cultures, here we show that innate lymphoid cells (ILCs), potent producers of interleukin-22 (IL-22) after intestinal injury, increase the growth of mouse small intestine organoids in an IL-22-dependent fashion. Recombinant IL-22 directly targeted ISCs, augmenting the growth of both mouse and human intestinal organoids, increasing proliferation and promoting ISC expansion. IL-22 induced STAT3 phosphorylation in Lgr5(+) ISCs, and STAT3 was crucial for both organoid formation and IL-22-mediated regeneration. Treatment with IL-22 in vivo after mouse allogeneic bone marrow transplantation enhanced the recovery of ISCs, increased epithelial regeneration and reduced intestinal pathology and mortality from graft-versus-host disease. ATOH1-deficient organoid culture demonstrated that IL-22 induced epithelial regeneration independently of the Paneth cell niche. Our findings reveal a fundamental mechanism by which the immune system is able to support the intestinal epithelium, activating ISCs to promote regeneration.

Effects of conditioning intensity in allogeneic stem cell transplantation for Philadelphia chromosome­positive acute lymphoblastic leukemia.

We retrospectively analyzed the outcomes of patients with Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL) who underwent first allogeneic stem cell transplantation (allo-SCT) at complete remission (CR) with myeloablative conditioning (MAC, n = 31) or reduced-intensity conditioning (RIC, n = 15) between 2001 and 2012. All the patients had received tyrosine kinase inhibitor (TKI)-based chemotherapy prior to allo-SCT. Overall survival (OS) rates (57 vs 63%, p = 0.53), leukemia-free survival rates (50 vs 65%, p = 0.29), and non-relapse mortality rates (39 vs 35%, p = 0.62) at 2 years were similar between the MAC and RIC groups. The minimal residual disease (MRD) status evaluated by sensitive polymerase chain reaction prior to allo-SCT did not influence the OS rate (77 vs 54%, p = 0.28) and leukemia-free survival rate (69 vs 51%, p = 0.48), irrespective of the conditioning intensity. Our data suggest that the RIC regimen may represent a sufficient intensity of therapeutic pre-transplant conditioning for patients with Ph+ALL who have maintained a hematological CR with TKI-combined chemotherapy.

The use of oral beclomethasone dipropionate in the treatment of gastrointestinal graft-versus-host disease: the experience of the Fukuoka blood and marrow transplantation (BMT) group.

OBJECTIVE: We examined the therapeutic strategies for treating mild gastrointestinal (GI) graft-versus-host disease (GVHD) using oral beclomethasone dipropionate (BDP) in 15 Japanese patients based on the donor source. The primary objective was to determine the efficacy and toxicity of oral BDP combined with/without low-dose prednisone (PSL). METHODS: Oral BDP was administered with 1 mg/kg/d of PSL in patients undergoing bone marrow transplantation (BMT) or peripheral blood stem cell transplantation (PBSCT; n=11), and the dose of PSL was tapered off after 22 days. Oral BDP alone was administered in patients undergoing cord blood stem cell transplantation (CBSCT; n=4). The primary endpoint was the rate of treatment success on day 49, as measured according to the improvement or complete resolution of GI symptoms without additional treatment. The secondary endpoints included treatment-related toxicity according to the National Cancer Institute Common Toxicity Criteria version 3.0, the rate of treatment discontinuation due to toxicity, the rate of relapse of acute GVHD by day 100 and the incidence of bacterial, fungal or viral infection, including cytomegalovirus (CMV) antigenemia. RESULTS: Treatment success was achieved in seven of the 11 (64%) patients undergoing BMT or PBSCT and in all four patients (100%) undergoing CBSCT. Subsequent adverse events included herpes zoster infection, catheter-associated sepsis and CMV enteritis; all affected patients responded well to treatment. CONCLUSION: The use of a risk-stratified treatment strategy with oral BDP depending on the stem cell source is effective in patients with mild GI-GVHD.

Combination of bortezomib, thalidomide, and dexamethasone (VTD) as a consolidation therapy after autologous stem cell transplantation for symptomatic multiple myeloma in Japanese patients.

Consolidation therapy for patients with multiple myeloma (MM) has been widely adopted to improve treatment response following autologous stem cell transplantation. In this study, we retrospectively analyzed the safety and efficacy of combination regimen of bortezomib, thalidomide, and dexamethasone (VTD) as consolidation therapy in 24 Japanese patients with newly diagnosed MM. VTD consisted of bortezomib at a dose of 1.3 mg/m(2) and dexamethasone at a dose of 40 mg/day on days 1, 8, 15, and 22 of a 35-day cycle, with daily oral thalidomide at a dose of 100 mg/day. Grade 3-4 neutropenia and thrombocytopenia were documented in four and three patients (17 and 13 %), respectively, but drug dose reduction due to cytopenia was not required in any case. Peripheral neuropathy was common (63 %), but severe grade 3-4 peripheral neuropathy was not observed. Very good partial response or better response (≥VGPR) rates before and after consolidation therapy were 54 and 79 %, respectively. Patients had a significant probability of improving from

Reciprocal expression of enteric antimicrobial proteins in intestinal graft-versus-host disease.

We recently demonstrated that expression of α-defensins, the major antimicrobial peptides produced by Paneth cells, was severely suppressed in mice with graft-versus-host disease (GVHD). In this study, we found that antibacterial lectin, regenerating islet-derived IIIγ (RegIIIγ) was upregulated in villous enterocytes, thus demonstrating the reciprocal control of enteric antimicrobial proteins in GVHD. Upregulation of RegIIIγ was mediated by a mechanism independent upon radiation-induced intestinal tract damage. MyD88-mediated signaling in intestinal epithelium was required for RegIIIγ upregulation in GVHD and antibiotic therapy downregulated RegIIIγ expression. These results suggest that MyD88-mediated sensing of the intestinal microbes disregulated in GVHD induces RegIIIγ upregulation in GVHD and argue a role for RegIIIγ in the pathogenesis of GVHD.

Combination of high-dose melphalan and bortezomib as conditioning regimen for autologous peripheral blood stem cell transplantation in multiple myeloma.

Bortezomib and melphalan have synergistic effects against multiple myeloma (MM) cells. We conducted a pilot study on the combination of bortezomib and high-dose melphalan (Bor-HDM) as a conditioning regimen followed by autologous stem cell transplant (ASCT) in 17 Japanese patients with newly diagnosed MM, in comparison with a historical control of patients who received high-dose melphalan (HDM) only followed by ASCT. Nine patients received a single dose of bortezomib 1.3 mg/m(2) on day -1 in combination with melphalan 100 mg/m(2) on days -3 and -2 (Bor1-HDM), and eight received two doses of bortezomib 1.3 mg/m(2) on days -4 and -1 (Bor2-HDM) in combination with HDM. Engraftment of autologous peripheral blood stem cells and regimen-related toxicities (RRT) were comparable among the HDM and Bor-HDM groups. Probability of upgrading from a less than very good partial response (VGPR) to VGPR after ASCT was approximately two times higher in the Bor-HDM group than in the HDM group. However, we observed no significant differences in engraftment, RRT, and response rates between the Bor1-HDM and Bor2-HDM groups. The present study showed that concurrent administration of at least two doses of bortezomib in combination with HDM can be safe in Japanese patients. Additional large prospective randomized trials are required to address the optimal dosages and schedules of bortezomib administration, as well as the efficacy of the Bor-HDM conditioning regimen for ASCT.

Higher incidence of injection site reactions after subcutaneous bortezomib administration on the thigh compared with the abdomen.

Subcutaneous (sc) rather than intravenous administration of bortezomib (Bor) is becoming more common for treating multiple myeloma (MM) because scBor results in lower incidence and severity of peripheral neuropathy and has equivalent efficacy. Bor is an irritant cytotoxic agent when it leaks out; therefore, it is recommended that injections of scBor should be rotated among eight different sites on the abdomen and thigh. However, detailed information about injection site reaction (ISR) has not been sufficiently documented. We retrospectively analyzed the incidence and severity of ISR following scBor administration in 15 Japanese patients with MM. Grade 1 ISR occurred following 40 of 158 (25.3%) scBor injections in ten patients, whereas grade 2 ISRs occurred following seven injections (4.4%) in five patients. Five patients did not develop ISR. Of note, grade 2 ISR was documented in 6 of 65 (9.2%) thigh injections but only in 1 of 93 (1.1%) abdominal injections. These data show that grade 2 ISRs were more common in the thigh compared with the abdomen possibly because the thigh contains lesser adipose tissue than the abdomen. Grade 2 ISRs resolved without any sequela within a median of 7 d. scBor administration on the abdomen instead of the thigh should be considered, especially for emaciated patients, because ISR rapidly resolves within the interval before the next injection even if it occurs.

Graft-versus-host disease disrupts intestinal microbial ecology by inhibiting Paneth cell production of α-defensins.

Allogeneic hematopoietic stem cell transplantation (SCT) is a curative therapy for various hematologic disorders. Graft-versus-host disease (GVHD) and infections are the major complications of SCT, and their close relationship has been suggested. In this study, we evaluated a link between 2 complications in mouse models. The intestinal microbial communities are actively regulated by Paneth cells through their secretion of antimicrobial peptides, α-defensins. We discovered that Paneth cells are targeted by GVHD, resulting in marked reduction in the expression of α-defensins, which selectively kill noncommensals, while preserving commensals. Molecular profiling of intestinal microbial communities showed loss of physiologic diversity among the microflora and the overwhelming expansion of otherwise rare bacteria Escherichia coli, which caused septicemia. These changes occurred only in mice with GVHD, independently on conditioning-induced intestinal injury, and there was a significant correlation between alteration in the intestinal microbiota and GVHD severity. Oral administration of polymyxin B inhibited outgrowth of E coli and ameliorated GVHD. These results reveal the novel mechanism responsible for shift in the gut flora from commensals toward the widespread prevalence of pathogens and the previously unrecognized association between GVHD and infection after allogeneic SCT.