Shuichiro Takashima

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.

The Wnt agonist R-spondin1 regulates systemic graft-versus-host disease by protecting intestinal stem cells

R-spondin1 stimulates the proliferation of intestinal stem cells through the Wnt signaling pathway and protects against graft-versus-host disease.

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.

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.

Injection site reaction after subcutaneous administration of bortezomib in Japanese patients with multiple myeloma

in patients treated with subcutaneous Bor (sBor) was nearly equal to that in patients treated with intravenous Bor (ivBor), although the incidence and severity of PN in patients treated with sBor was lower than those in patients treated with ivBor [2‐4]. The most common injection site reaction was erythema, however, only four patients (3 %) developed an injection site reaction of grade 3 or more, necessitating a reduction in Bor dose in two (1 %) patients [3]. The injection site reactions in the other two patients treated with sBor were severe, although detailed information regarding the clinical courses following these reactions was not provided [3]. According to a classification of skin symptoms, Bor is classified as an irritant, as it causes extravasation of cytotoxic agents [5]. Further studies that focus on injection site reaction of sBor, particularly in Japanese patients, are required. The present study retrospectively analyzed injection site reactions in 19 Japanese patients with newly diagnosed (n = 9) or relapsed (n = 10) MM, and who were treated with sBor at a concentration of 2.5 mg/ml (3.0 mg Bor reconstituted with 1.2 ml normal saline), as described previously [3], between April 2011 and June 2012. We injected bortezomib to eight different sites in the right and left abdomen, upper and lower quadrant, or right and left thigh, proximal and distal sites of each patient in turn, as described previously [3]. These patients were treated with weekly BD (Bor 1.3 mg/m 2 on day 1, 8, 15, 22, and

Low incidence of adenovirus hemorrhagic cystitis following autologous hematopoietic stem cell transplantation in the rituximab era

Viral hemorrhagic cystitis (HC) is a frequent complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT) but is rare after autologous peripheral blood stem cell transplantation (auto-PBSCT) because immunosuppression is not required in the absence of an allogeneic immune reaction. Recently, auto-PBSCT has been combined with novel anticancer agents targeting specific molecules, such as rituximab; however, these may cause severe immune deficiency and increase the susceptibility of transplant recipients to opportunistic infections. To address this issue, we performed a retrospective analysis of the incidence of viral HC in auto-PBSCT recipients. Of 158 recipients, only 4 cases (2.5%) were diagnosed with viral HC due to adenovirus (ADV), which was significantly less frequent compared with the incidence in allo-HSCT recipients (15.8%). The incidence of HC did not increase with rituximab treatment. This was a single-center retrospective analysis with a small sample size; however, incorporation of rituximab into the treatment of auto-PBSCT recipients did not appear to be a risk factor for developing viral HC. Viral HC is a noteworthy complication after HSCT because of its negative effects on the quality of life and its potential to cause therapy-related mortality [1]. We recently reported different risk factors associated with two viral HCs in allo-HSCT recipients [2]: ADV-HC and BKV-HC. ADV-HC is associated with severe immunodeficiency caused by immunosuppression therapies such as T-cell purging, whereas BKV-HC is associated with allogeneic immune hyperactivity such as graft-versus-host disease (GVHD) or the pre-engraftment immune reaction (PIR) [3]. Auto-PBSCT is characterized by rapid hematologic and immune reconstitution and does not trigger an allogeneic immune reaction that would require immunosuppressive therapy either for prophylaxis or for treatment. Consequently, there is lower incidence and severity of opportunistic infection including viral HC in auto-PBSCT recipients [4,5]. The survival of auto-PBSCT recipients has significantly improved over the recent years because of the incorporation of novel anticancer agents targeting specific molecules into the treatment regimen [6]. One such anticancer agent widely used in this context is rituximab, a chimeric monoclonal anti-CD20 antibody that causes B-lymphocyte depletion. When used alone in patients with lymphoma, rituximab has few effects on the incidence of infectious complications [7,8]. However, the combination of rituximab and high-dose chemotherapy (HDC) may increase the risk of viral infections [9–11], including that caused by the hepatitis-B virus (HBV) [12]. This retrospective study was conducted to clarify the prevalence, clinical features, and risk factors of viral HC after auto-PBSCTand to compare these variables with those of allo-HSCT. A total of 158 patients with hematological disorders or solid tumors hospitalized at our institute from 2000 to 2010 were enrolled. The clinical characteristics of these patients are summarized in Table I. A total of 101 patients had malignant lymphoma (ML), and the remaining 57 patients were diagnosed with acute myelogenous leukemia (AML; n 5 13), plasma-cell disorders (e.g., multiple myeloma or primary amyloidosis; n 5 36), or solid tumors (n 5 8). Patients with one of the following conditions were classified as ‘‘chemotherapy-sensitive’’ (n 5 132): ML and plasma cell disorders in at least partial remission and AML in first complete remission. All other patients (n 5 26) were categorized as ‘‘chemotherapy-resistant.’’ A total of 101 ML patients were treated with the CHOP regimen [13] as induction therapy, HDC as a preparative conditioning regimen, followed by transplantation of unpurged autologous PBSCs. After approval of rituximab for the treatment of ML in Japan, 41 patients with CD20-positive lymphomas was treated with CHOP and auto-PBSCT combined with rituximab. Of these, 35 patients received rituximab in combination with the ranimustine, carboplatin, etoposide, and cyclophosphamide (MCEC) pretransplant regimen [14]. Four patients received rituximab combined with the melphalan, etoposide, cyclophosphamide, and dexamethasone (LEED) regimen [15] and 2 patients received rituximab in combination with other regimens. The remaining 60 ML patients were either treated before approval of the use of rituximab or had CD20-negative lymphoma and received HDC consisting of MCEC (n 5 52), LEED (n 5 2), or another regimen (n 5 6), all without rituximab. Plasma cell disorders (n 5 36) were treated with the VAD regimen [16] or bortezomib-based induction therapy followed by high-dose melphalan before auto-PBSCT [17]. Standard-risk AML patients (n 5 13) achieved complete remission after conventional remission induction and consolidation chemotherapy and received the busulfan, cytarabine, and etoposide (BEA) conditioning regimen followed by auto-PBSCT [18]. Eight patients with solid tumors underwent standard chemotherapies based on each diagnosis and then received auto-PBSCT. Of these, five patients received the high-dose ICE regimen [19]. Acyclovir prophylaxis was used to protect against reactivation of herpes simplex virus (HSV) in all these recipients. Urinalysis was routinely performed at least once a week from the initiation of preparative regimens until discharge from hospital or when clinical signs of cystitis appeared after the discharge. Microscopic or macroscopic hematuria and/or bladder irritation was further analyzed using polymerase chain reaction (PCR) to detect viral DNA (ADV, BKV, and JC virus). Methods for detecting each type of viral DNA have been reported previously [20–22]. In brief, after 2 ml of a urine sample was centrifuged (15,000g for 1 hr), DNA was purified from the sediment using the QIAmp DNA Blood Mini Kit (Qiagen, Hilden, Germany). Next, 5 ml of purified DNA was subjected to PCR using the GeneAmp Kit and GeneAmp PCR System 9600 (PerkinElmer, Boston, MA) with the following primers: AD185S (50-tccagcaacttcatgtccatgg-30) and AD 185A (50-tcgatgacgccgcggt30) for detecting ADV; BKV-1 (50-gcaagtgccaaaactactaat-30) and BKV-2 (50tgcatgaaggttaagcatgc-30) for detecting BKV; and JTP-1 (50-gcagcttagtgattttct-

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.