Over‐expression of BACH2 is related to ongoing somatic hypermutation of the immunoglobulin heavy chain gene variable region of de novo diffuse large B‐cell lymphoma

The basic region–leucine zipper (bZip) factor BTB, CNC homology 2 (BACH2) is known to have important roles in class switch recombination and somatic hypermutation (SHM) of the immunoglobulin (Ig) gene. In this study, we investigated the relationship between the expression of BACH2 and the status of SHM of the Ig heavy chain gene variable region (IgHV) for SHM in diffuse large B‐cell lymphoma (DLBCL). We examined 20 cases of DLBCL, 13 of which were germinal center B‐cell (GCB) DLBCL and 7 were non‐GCB DLBCL. Seven cases were negative, 6 were positive (cytoplasmic expression) and 7 were strongly positive (both nuclear and cytoplasmic expression) for BACH2. Confirmed mutation (CM) was identified in 8 cases and the CM index (number of confirmed mutations per 10 subclones) was distributed from 0 to 5. A CM index of 7 strongly positive (over‐expression) cases with BACH2 were distributed from 0 to 5, and that of 7 negative and 6 positive cases were distributed from 0 to 1. Over‐expression of BACH2 was statistically related to CM index (P = 0.008). In conclusion, over‐expression of BACH2 is critical for ongoing SHM of IgHV in DLBCL, and our data suggest that BACH2 may play an essential role for SHM of the Ig gene in B‐cell lymphoma.     

Interleukin-18 levels reflect the long-term prognosis of acute lung injury and acute respiratory distress syndrome

Purpose

The purpose of this study was to investigate the relationship between the blood levels of interleukin (IL)-18 measured in the early stage of acute respiratory failure and the prognosis for patient survival.

Methods

The study subjects were 38 patients with acute respiratory failure treated at our institution during the 4-year period from April 2004 to March 2008. The underlying clinical condition was defined as acute respiratory distress syndrome (ARDS; n?=?12) or acute lung injury (ALI; n?=?26). The serum levels of interleukin (IL)-18, IL-12, and tumor necrosis factor (TNF)-α were measured by enzyme-linked immunosorbent assays.

Results

The ARDS group showed significantly higher serum levels of IL-18, IL-12, and TNF-α even at an early stage after disease onset compared with the ALI group. A negative correlation was noted between the PaO₂/FIO₂ ratio (P/F ratio) and serum IL-18 level. Analysis of all 38 patients with ALI/ARDS revealed a 30-day mortality rate of 7.9?%, 60-day mortality rate of 15.8?%, and 90-day mortality rate of 18.4?%. The early-stage serum levels of IL-18, IL-12, and TNF-α were significantly higher in the non-survivors at 60 and 90?days, but not at 30?days, than in the corresponding survivors.

Conclusion

The present data demonstrate an inverse correlation between serum IL-18 level and the P/F ratio, suggesting the possible involvement of IL-18 in the pathogenesis of respiratory failure in patients with ALI/ARDS. Early-stage serum IL-18, IL-12, and TNF-α levels appear to reflect the >60-day prognosis in patients with ALI/ARDS.     

Islet purification method using large bottles effectively achieves high islet yield from pig pancreas

Porcine islets are a promising resource for xenotransplantation. However, low efficacy of islet isolation because of their marked fragility remains a problem. Recently we found that the standard purification method using COBE 2991 cell processor (COBE) with Ficoll density gradient solution damaged islets mechanically by high shearing force. In this study, we evaluated our new purification method using large plastic bottles for the efficacy of islet purification. Ten porcine pancreata were used. The average warm ischemic time was over 40 min; therefore, these pancreata were considered to be in a marginal condition. After digestion, the digested tissue was divided into three groups. Each group was purified using either top loading method with bottle (top group) or bottom loading method with bottle (bottom group) or standard COBE method (COBE group). Islet yield per pancreas weight (IEQ/g) and the rate of postpurification recovery in the top group were significantly higher than the COBE group (top: 8060 ± 1652 IEQ/g, bottom: 4572 ± 614 IE/g, COBE: 3900 ± 734 IE/g. p < 0.02 in top vs. COBE; top percentage of recovery: 99.3 ± 12.3%, bottom: 62.6 ± 8.8%, COBE: 49.5 ± 6.7%, p < 0.02 in top vs. bottom and COBE). The average sizes of purified islets in the top and bottom groups were significantly larger than COBE group (Average diameter top: 156 ± 8 μm, bottom: 147 ± 6 μm, COBE: 119 ± 6 μm, p < 0.01 in top vs. COBE and in bottom vs. COBE), which indicated that bottle method can reduce shear force during purification. Our new purification using top loading bottle method enabled us to obtain a high yield of porcine islets from marginal pancreata.     

Chicken HS4 Insulators Have Minimal Barrier Function Among Progeny of Human Hematopoietic Cells Transduced With an HIV1-based Lentiviral Vector

Position effects limit the curative potential of gene transfer strategies for the hemoglobinopathies by inducing clonal variability of transgene expression. We evaluated the mitigating effects of the chicken hypersensitivity site 4 (HS4) insulator among lentiviral vector-transduced human hematopoietic cells. We constructed various lentiviral vectors using a green fluorescent protein (GFP) reporter under the control of a reverse-oriented murine stem cell virus (MSCV)-long-term repeat (LTR) promoter or a reverse-oriented β-globin expression cassette. A full-length HS4, a tandem HS4 core, and a single core insulator were inserted into the 3′ LTR in both forward and reverse orientation. All but the reverse single core insulator significantly decreased titers. All reduced %GFP without increasing mean fluorescence intensity (MFI) among erythroid progeny of transduced human CD34⁺ cells. A lower coefficient of variation (CV) was observed only among progeny of the full-length vector-transduced cells, yet a fivefold reduction in transduction efficiency was observed. In xenografted mice, the single core insulator decreased both the %GFP and the MFI at 4 and 8 weeks after transplantation with no difference in CVs. These data demonstrate that the inclusion of HS4 insulator elements lowers viral titers, reduces efficiency of transduction, and produces minimal effects on transgene expression among human hematopoietic cells in vitro and in vivo.     

Markedly improved glycemic control and enhanced insulin sensitivity in a patient with type 2 diabetes complicated by a suprasellar tumor treated with pioglitazone and metformin

A patient with type 2 diabetes and hypothalamic damage due to a suprasellar tumor developed impaired glycemic control and central obesity. The patient showed exaggerated adrenocorticotropic hormone responsiveness as determined by a corticotrophin releasing hormone test and elevated serum leptin concentrations associated with ravenous appetite and insulin resistance mediated in part through disturbances in leptin signaling. Combination treatment with metformin and pioglitazone was markedly effective in improving glycemic control. Additionally, metformin treatment showed marked anorectic effects on the hyperphagia. This case has important implications for the pathogenesis and management of diabetes in patients with hypothalamic-pituitary-adrenal axis deficiencies.     

Prevention by rebamipide of acute reflux esophagitis in rats

Proinflammatory factors, including neutrophil-derived oxygen free radicals and inflammatory cytokines, have recently been implicated in the pathogenesis of reflux esophagitis. Rebamipide has been widely used as an anti-ulcer agent. The aim of the present study was to assess the protective effect of rebamipide against acute reflux esophagitis in rats. Esophagitis was induced in rats by ligation at the limiting ridge and the lower portion of the duodenum. Vehicle or rebamipide were given as a single dose intraduodenally. Lesion index (LI), thiobarbituric acid-reactive substances (TBA-RS), myeloperoxidase (MPO) activity, mRNA and protein of tumor necrosis factor (TNF)-alpha and cytokine-induced neutrophil chemoattractant (CINC)-1 in the esophageal mucosa were markedly increased; pretreatment with rebamipide, however, significantly reduced both macroscopic and microscopic injuries and increases in inflammatory mediators. The results of this study indicate that rebamipide protects against the occurrence of esophagitis and has highly promising potential as a new therapeutic agent for reflux esophagitis.     

Desmocollin 2 is a new immunohistochemical marker indicative of squamous differentiation in urothelial carcinoma

Hayashi T, Sentani K, Oue N, Anami K, Sakamoto N, Ohara S, Teishima J, Noguchi T, Nakayama H, Taniyama K, Matsubara A & Yasui W
(2011) Histopathology 59 , 710–721
Desmocollin 2 is a new immunohistochemical marker indicative of squamous differentiation in urothelial carcinoma Aims: Urothelial carcinoma (UC) with squamous differentiation tends to present at higher stages than pure UC. To distinguish UC with squamous differentiation from pure UC, a sensitive and specific marker is needed. Desmocollin 2 (DSC2) is a protein localized in desmosomal junctions of stratified epithelium, but little is known about its biological significance in bladder cancer. We examined the utility of DSC2 as a diagnostic marker. Methods and results: We analysed the immunohistochemical characteristics of DSC2, and studied the relationship of DSC2 expression with the expression of the known markers uroplakin III (UPIII), cytokeratin (CK)7, CK20, epidermal growth factor receptor (EGFR), and p53. DSC2 staining was detected in 24 of 25 (96%) cases of UC with squamous differentiation, but in none of 85 (0%) cases of pure UC. DSC2 staining was detected only in areas of squamous differentiation. DSC2 expression was mutually exclusive of UPIII expression, and was correlated with EGFR expression. Furthermore, DSC2 expression was correlated with higher stage (P = 0.0314) and poor prognosis (P = 0.0477). Conclusions: DSC2 staining offers high sensitivity (96%) and high specificity (100%) for the detection of squamous differentiation in UC. DSC2 is a useful immunohistochemical marker for separation of UC with squamous differentiation from pure UC.     

Mantle cell lymphoma with EBV-positive Hodgkin and Reed–Sternberg-like cells in a patient after autologous PBSCT: Phenotypically distinct but genetically related tumors

The case of 70-year-old man with mantle cell lymphoma (MCL) carrying t(11;14) translocation that relapsed as nodal lymphoma combining MCL and classic Hodgkin lymphoma (cHL) 9 years after autologous peripheral blood stem cell transplant (auto-PBSCT) is reported. Lymph nodes contained two separate areas of MCL and cHL-like components. Hodgkin and Reed–Sternberg (HRS)-like cells were accompanied by a prominent histiocyte background. HRS-like cells were CD5⁻, CD15⁺, CD20⁻, CD30⁺, PAX5⁺, Bob.1⁻, Oct2⁻ and EBER⁺. The MCL component expressed cyclin D1 and SOX11, whereas cyclin D1 and SOX11 expressions were reduced and lost, respectively, in HRS-like cells. Polymerase chain reaction results showed a single clonal rearrangement of the IGH gene in MCL and cHL-like components. CCND1 break apart fluorescence in situ hybridization showed split signals in both MCL and HRS-like cells, suggesting that MCL and cHL-like components were clonally related. Acquisition of p53 expression and Epstein–Barr virus (EBV)-positivity was seen in HRS-like cells. The patient died of disease progression with elevated hepatobiliary enzymes. The autopsy showed both MCL and cHL-like components around the bile ducts, splenic white pulp and bone marrow. The two components were phenotypically distinct, but genetically related, suggesting that transformation of MCL to HRS-like cells during the course of MCL in association with EBV infection.