Characterization of an epimastigote-stage-specific hemoglobin receptor of Trypanosoma congolense

Background: Since Trypanosorna spp. lack a complete heme synthesis pathway, the parasites are totally dependent on their host for heme throughout all of the stages of their life -cycle. We herein report the identification and characterization of a T. congolense epimastigote form (EMF)-specific hemoglobin (Hb) receptor. The gene was initially reported to encode a T. congolense haptoglobin (Hp)-Hb complex receptor (TcHpHbR) based on its similarity to a gene encoding a T brucei Hp-Hb complex receptor (TbHpHbR). Methods: Trypanosorna congolense IL3000 was used in this study. A TcHpHbR gene was PCR amplified from the parasite genome. The recombinant protein was used as an immunogen to raise antibodies for immunofluorescence assay and immunoblotting. Hemoglobin uptake by the parasite was examined by using Alexa 488 labelled Hb and visualized by confocal laser scanning microscopy. The qualitative and quantitative interaction between TcHpHbR and its ligand were measured using a surface plasmon resonance assay. Results: We found that, unlike TbHpHbR, TcHpHbR was exclusively expressed in the EMF stage at RNA and protein levels. The recombinant TcHpHbR (rTcHpHbR) was co-precipitated with free-Hb in a GST-pull down assay. Surface plasmon resonance revealed that rTcHpHbR binds free-Hb with high affinity (dissociation constant (K,A) =2.1x10(-8) M) but free-Hp with low affinity (Kd = 2.2x10(-7) M). Furthermore, Alexa 488-labelled-Hb was only taken up by the EMF and co-localized with tomato lectin, which is a marker of endocytic compartments (flagellar pocket and lysosome). Conclusion: We conclude that the T. congolense EMF takes up free-Hb via TcHpHbR, a receptor which is specific to this developmental stage. We therefore propose renaming TcHpHbR as T congolense EMF-specific Hb receptor (TcEpHbR)

Histologic Transformation from Follicular Lymphoma to Diffuse Large B-cell Lymphoma Detected during Colonoscopy

A 77-year-old Japanese woman who had been treated for follicular lymphoma for 8 years developed abdominal pain and intra-abdominal lymphadenopathies. Colonoscopy revealed an elevated lesion in the rectum, which presented as two humps with erosions. A diagnosis of histologic transformation of follicular lymphoma to diffuse large B-cell lymphoma was made by endoscopic biopsy. This case underscores the importance of endoscopy examinations and biopsy of newly emerged gastrointestinal lesions for the prompt diagnosis of histologic transformation, since salvage chemotherapy must be initiated quickly in such cases

Laparoscopic Hepatectomy for the Patient with Hemophilia A with High Titer Factor VIII Inhibitor

We present the first case of laparoscopic left lateral segmentectomy for hepatocellular carcinoma (HCC) in a patient with hemophilia A, acquired hepatitis C, and high-titer factor VIII inhibitor, which was confirmed by preoperative diagnosis. He underwent laparoscopic left lateral segmentectomy with the administration of recombinant activated factor VII. Surgery could be performed with reduced intraoperative hemorrhage. He experienced postoperative intra-abdominal wall hemorrhage, which was successfully managed with red cell concentrates transfusion and administration of recombinant activated factor VII. Laparoscopic hepatectomy can be applied for hemophilia patients with high titer inhibitors

Effects of Gram-negative Rod Blood Stream Infection on Acute GVHD in Allogeneic Hematopoietic Stem Cell Transplantation: A Single-institute Analysis

A bloodstream infection (BSI) is the most common serious infectious complication of hematopoietic stem cell transplantation (HSCT). BSI promotes an inflammatory state, which exacerbates acute graft-versus-host disease (GVHD). We investigated whether a Gram-negative rod bloodstream infection (GNR-BSI), which develops early after allo-HSCT, affected the onset or exacerbated acute GVHD in 465 patients who underwent allo-HSCT from 1995 through 2015 at a single institution. Eighty-eight patients (19%) developed BSI during the study period. Among the cultures, 50 (57%) were Gram-positive cocci (GPC) and 31 (35%) were GNR. Of the 465 patients, 187 (40%) developed acute GVHD of grade II or higher within the first 100 days post-allogeneic HSCT: 124 (27%) had acute GVHD grade II, 47 (10%) had grade III, and 16 (3%) had grade IV. Multivariate analysis revealed that GNR-BSI was a significant risk factor for grade II-IV acute GVHD (grade II-IV: hazard ratio [HR] 1.75, 95% confidence interval [CI] 1.03-2.97; grade III-IV: HR 2.37, 95% CI 1.03-5.43). These results suggest that GNR-BSI may predict the onset and exacerbation of acute GVHD

Analysis of Immunity against Measles, Mumps, Rubella, and Varicella Zoster in Adult Recipients of Allogeneic Hematopoietic Stem Cell Transplantation: A Single-Center Experience

Vaccine-preventable disease (VPD) infections are more severe in immunocompromised hosts. Vaccination against measles, mumps, rubella, and varicella zoster (VZV) (MMRV) is therefore recommended for hematopoietic stem cell transplantation (HCT) recipients. However, studies on adult HCT recipients with VPD infections are limited. At our institution, we have systematically conducted serological MMRV tests as a part of check-up examinations during long-term follow-up (LTFU) after HCT since 2015. This retrospective study aimed to evaluate changes in the serostatus between before and 2 years after allogeneic HCT. Among 161 patients, the pre-transplant seropositivity was 82.7% for measles, 86.8% for mumps, 84.2% for rubella, and 94.3% for VZV. Among 56 patients who underwent LTFU including serological MMRV tests at 2 years after HCT, the percentages maintaining seroprotective antibody levels for measles, mumps, rubella and VZV were 71.5% (40/56), 51.8% (29/56), 48.2% (27/56), and 60.7% (34/56), respectively. Vaccination was recommended for 22 patients, and 12 were vaccinated. Among the 12 vaccinated patients, rates of seroconversion were examined in 2-6 patients for each of the four viruses. They were 100% (3/3) for measles, 33.3% (1/3) for mumps, 50% (3/6) for rubella, and 0% (0/2) for VZV. Further studies are warranted to clarify the effect of vaccination in adult HCT recipients

Intestinal Diffuse Large B-Cell Lymphoma in a Patient with Systemic Lupus Erythematosus

A 44-year-old Japanese woman with systemic lupus erythematosus (SLE) presented to our hospital with abdominal pain. Radiological and endoscopic examinations led to the diagnosis of diffuse large B-cell lymphoma of the jejunum, which was subsequently resected. Patients with SLE reportedly have an increased risk of non-Hodgkin lymphoma, as demonstrated by our patient. Hence, lymphoma should be considered in the differential diagnosis of neoplastic lesions emerging in SLE patients. In addition, flow cytometry using endoscopically biopsied fragments is useful for the immediate diagnosis of lymphoma, leading to timely and accurate preoperative staging

Combination of reduced post-transplant cyclophosphamide and early tacrolimus initiation increases the incidence of chronic graft-versus-host disease in human leukocyte antigen-haploidentical peripheral blood stem-cell transplantation

We evaluated the clinical impacts of the concurrent modification of post-transplant cyclophosphamide (PTCy) dose and tacrolimus (Tac)-initiation timing in 61 patients with human leukocyte antigen-haploidentical transplantation. Reduced-dose PTCy (80 mg/kg) was associated with a higher incidence of moderate-to-severe chronic graft-versus-host disease (GVHD) than standard-dose PTCy (100 mg/kg) (35.0% vs. 26.6%, p = 0.053). Notably, early-initiation Tac (day -1) increased moderate-to-severe chronic GVHD than standard-initiation Tac (day 5) in the reduced-dose PTCy group (p = 0.032), whereas Tac-initiation timing did not impact chronic GVHD in the standard-dose PTCy group. These data indicate that the combination of reduced-dose PTCy and early-initiation Tac can amplify chronic GVHD

Antitumor activity of α-pinene in T-cell tumors

T-cell acute leukemia and lymphoma have a poor prognosis. Although new therapeu-tic agents have been developed, their therapeutic effects are suboptimal. α- Pinene, a monoterpene compound, has an antitumor effect on solid tumors; however, few comprehensive investigations have been conducted on its impact on hematologic ma-lignancies. This report provides a comprehensive analysis of the potential benefits of using α- pinene as an antitumor agent for the treatment of T-cell tumors. We found that α- pinene inhibited the proliferation of hematologic malignancies, especially in T- cell tumor cell lines EL-4 and Molt-4, induced mitochondrial dysfunction and re-active oxygen species accumulation, and inhibited NF-κB p65 translocation into the nucleus, leading to robust apoptosis in EL-4 cells. Collectively, these findings suggest that α- pinene has potential as a therapeutic agent for T-cell malignancies, and further investigation is warranted