Human T-cell Lymphotropic Virus Type-1-associated Bronchioloalveolar Disorder with Non-necrotizing Granulomas: A Case Report and Literature Review.

Human T-cell lymphotropic virus type-1 (HTLV-1)-associated bronchioloalveolar disorder (HABA) is a pulmonary disorder characterized by lymphocytic infiltration of the peribronchiolar space and interstitium in HTLV-1 carriers and in adult T-cell leukemia/lymphoma (ATLL). We herein report an 85-year-old woman carrying HTLV-1 with HABA who presented with a miliary pattern of micronodules in both lungs on high-resolution computed tomography and a lymphocytic infiltrate with non-necrotizing granulomas on pathology. This rare case of HABA should be differentiated from sarcoidosis, hypersensitivity pneumonitis, or miliary tuberculosis.

Paradoxical Expression of R-10G-reactive Antigen in Human Testicular Embryonal Carcinoma.

Thus far, several monoclonal antibodies directed against cell-surface carbohydrate antigens have been generated. Among them, R-10G reportedly reacts selectively with human embryonic stem and induced pluripotent stem cells, but not with embryonal carcinoma (EC) cells. However, EC cells derived from patients' EC tumors may exhibit varying levels of R-10G-reactive antigen expression. Thus, we asked whether human EC tissues or germ cell tumor (GCT) tissues other than EC express R-10G-reactive antigen. To do so, we quantitatively analyzed R-10G-reactive antigen expression in 83 testicular GCT surgical specimens containing a total of 125 various GCT components. Accordingly, in all EC components examined, the EC cell plasma membrane was immunolabeled with R-10G, while most seminoma components were R-10G-negative. In non-seminomatous GCT (NSGCT) other than EC (non-EC NSGCT), R-10G-reactive antigen expression was variable, but signal distribution was focal, and the average intensity was weaker than that seen in EC. The percentages of R-10G-positive cells in these three groups varied with high statistical significance (p<0.001 for all combinations). These findings indicate that the R-10G-reactive antigen is preferentially expressed in human testicular EC tissues and, thus, could be used as a diagnostic marker for this malignancy.

The Percentage of PNAd-Expressing Vessels is Correlated with Disease Severity in Eosinophilic Chronic Rhinosinusitis.

BACKGROUND: Eosinophilic chronic rhinosinusitis (ECRS) is a chronic inflammatory condition of the paranasal sinuses characterized by intractable nasal polyps with prominent eosinophil infiltration. These eosinophils are presumably recruited from peripheral blood via vessels expressing peripheral lymph node addressin (PNAd), a set of glycoproteins decorated with 6-sulfo sialyl Lewis x (sLex) glycans that serve as L-selectin ligands. Based on the severity classification algorithm proposed by the Japanese Epidemiological Survey of Refractory Eosinophilic Chronic Rhinosinusitis (JESREC) study group, ECRS is divided into mild, moderate and severe groups; however, as yet there are few reports comparing the clinicopathological differences among these groups. OBJECTIVE: Our goal was to elucidate clinicopathological differences among the three different severities of ECRS with special reference to eosinophils and PNAd-expressing vessels. METHODS: We performed quantitative immunohistochemical analysis of PNAd-expressing vessels using surgical specimens of nasal polyps from patients exhibiting varying severity of ECRS (n = 35) and from individuals with non-ECRS (n = 10). To this end, we immunostained tissue sections with anti-PNAd and anti-CD34 monoclonal antibodies, and then determined the number of vessels immunolabeled with each antibody. RESULTS: The number of eosinophils infiltrating nasal polyps was correlated with ECRS severity. We also found that the PNAd + /CD34 + vessel ratio, namely, the percentage of PNAd-expressing vessels among all vessels, was positively correlated not only with ECRS severity but also with the number of eosinophils infiltrating nasal polyps formed in ECRS. CONCLUSION: These results strongly suggest that PNAd-expressing vessels play at least a partial role in eosinophil recruitment to nasal polyps and consequent severity of ECRS.

Expression and Clinical Significance of Spi-B in B-cell Acute Lymphoblastic Leukemia.

Spi-B, a member of the E26 transformation-specific (ETS) family of transcription factors, plays an important role in B cell differentiation. Spi-B also functions in development of diffuse large B-cell lymphoma; thus, we hypothesized that it may participate in leukemogenesis of B-cell acute lymphoblastic leukemia (B-ALL). To test this hypothesis, we first generated an anti-Spi-B monoclonal antibody that recognized Spi-B on formalin-fixed, paraffin-embedded tissue sections. This antibody, designated S28-5, selectively stained B cell nuclei at the pre-plasma cell stage (including centrocytes and centroblasts in germinal centers) and nuclei of plasmacytoid dendritic cells, but not fully differentiated plasma cells, T cells, macrophages, or follicular dendritic cells. Employing S28-5, we then performed immunohistochemical staining of bone marrow aspiration biopsy specimens obtained from B-ALL patients (n=62). Cases that showed stronger nuclear S28-5 signals than T-cell ALL were scored positive. In 26 (42%) of 62 specimens, leukemic cells showed nuclear Spi-B expression, and positivity was associated with patient age at diagnosis, and serum uric acid and creatinine levels. Moreover, Spi-B-positive patients demonstrated significantly shorter overall survival than did Spi-B-negative patients. These results suggest that Spi-B expression may serve as a prognostic indicator of B-ALL.

Vascular E-selectin Expression Detected in Formalin-fixed, Paraffin-embedded Sections With an E-selectin Monoclonal Antibody Correlates With Ulcerative Colitis Activity.

It is widely accepted that E-selectin, an inducible endothelial cell adhesion molecule, plays a critical role in the initial step of neutrophil recruitment to sites of acute inflammation. However, immunohistological analysis of E-selectin has been hampered by lack of E-selectin-specific monoclonal antibodies that can stain formalin-fixed, paraffin-embedded (FFPE) tissue sections. Here, we employed E-selectin•IgM (a soluble form of E-selectin) as immunogen, and then, after negative selection with L-selectin•IgM and P-selectin•IgM and screening of FFPE sections of both COS-1 cells overexpressing E-selectin and acute appendicitis tissues, we successfully generated an E-selectin-specific monoclonal antibody capable of staining FFPE tissue sections. We used this antibody, designated U12-12, to perform quantitative immunohistological analysis of 390 colonic mucosal biopsy specimens representing ulcerative colitis. We found that the higher the histological disease activity, the greater the number of vessels expressing E-selectin, an observation consistent with previous analyses of frozen tissue sections. Furthermore, in active ulcerative colitis, E-selectin-expressing vessels contained neutrophils attached to endothelial cells, presumably in the process of extravasation, which eventually could cause epithelial damage. These results overall indicate that U12-12 is effective for E-selectin immunohistochemistry in archived FFPE samples representing various human diseases.

Apical Membrane Expression of Distinct Sulfated Glycans Is a Characteristic Feature of Ductules and Their Reactive and Neoplastic Counterparts.

Intrahepatic bile ducts transport bile between bile canaliculi and the extrahepatic bile duct. The luminal surface of this tract is lined by a layer of biliary epithelial cells, or cholangiocytes, which secrete mucins consisting of scaffold proteins and O-glycosidically linked carbohydrate side chains. Although mucin core proteins have been extensively investigated, the structure and function of carbohydrate side chains have not. Here, we demonstrate that distinct sulfated glycans positive for MECA-79, R-10G, and 297-11A, but not 5D4, monoclonal antibodies are expressed in the cytoplasm of cells of large-sized ducts and in the apical membrane of cells in ductules, and that R-10G immunolabeling is partially eliminated by endo-ß-galactosidase digestion, supporting the presence of N-acetylglucosamine-6-O-sulfated N-acetyllactosamine structures. We observed comparable apical membrane-predominant staining in ductular reactions seen during regeneration that occurs in various liver diseases and in cholangiolocarcinoma, a subtype of small duct-type intrahepatic cholangiocarcinoma (iCCA). Apical membrane expression of distinct sulfated glycans in large duct-type iCCA was negligible. Intriguingly, under pathological conditions, endo-ß-galactosidase digestion almost completely eliminated R-10G immunoreactivity. These findings suggest that apical membrane expression of distinct sulfated glycans is a characteristic feature of ductules and their reactive and neoplastic counterparts.

Expression of functional E-selectin ligands on the plasma membrane of carcinoma cells correlates with poor prognosis in clear cell renal cell carcinoma.

OBJECTIVES: Given the relatively high frequency of metastatic recurrence of clear cell renal cell carcinoma (ccRCC), reliable prognostic markers of ccRCC, particularly those associated with metastasis, are needed. Here, in search of those factors, we assessed the contribution of sialyl Lewis x (sLex) and sialyl Lewis a (sLea), as well as functional E-selectin ligand carbohydrates expressed on carcinoma cells, to metastasis and consequent poor prognosis in ccRCC. MATERIALS AND METHODS: Patients who underwent surgical resection (curative nephrectomy) for RCC, and whose post-operative pathological diagnosis was ccRCC (n = 117) were enrolled in this study. Expression of sLex/sLea carbohydrate antigens in ccRCC was evaluated by immunohistochemistry with an anti-sLex/sLea monoclonal antibody HECA-452. To evaluate membrane expression of sLex/sLea carbohydrate antigens quantitatively, we employed a histological scoring system used to evaluate membrane expression of human epidermal growth factor receptor 2 (HER2) in breast cancer. We also conducted an E-selectin•IgM chimera in situ binding assay to assess expression of functional E-selectin ligand carbohydrates in ccRCC. We then carried out statistical analysis to determine whether membrane expression of HECA-452-reactive sLex/sLea glycans as well as of E-selectin•IgM-binding functional E-selectin ligand carbohydrates correlates with progression-free, overall, or cancer-specific survival. RESULTS: Based on HECA-452 immunochemistry, 106 of 117 ccRCC specimens expressed detectable levels of sLex/sLea glycans, primarily on the plasma membrane, and of those, 31 that showed robust membrane expression were judged as HECA-452-positive. Membrane expression of HECA-452-positive sLex/sLea glycans correlated with shortened progression-free and overall survival. Moreover, in in situ analysis, these HECA-452-positive ccRCC tissues were decorated with E-selectin•IgM chimeric proteins, calcium-dependently. Comparable analysis in normal kidney showed both HECA-452 positivity and chimera binding almost exclusively in epithelial cells that constitute proximal tubules. Membrane expression of functional E-selectin ligand carbohydrates, as detected by the E-selectin•IgM chimera, correlated more significantly with poor prognosis of patients, namely, shortened progression-free, overall and cancer-specific survival, than did HECA-452 positivity. CONCLUSIONS: Expression of E-selectin•IgM-binding functional E-selectin ligand carbohydrates can serve as a reliable and potentially superior prognostic biomarker of patients with ccRCC.

Suppression of viral replication by drs tumor suppressor via mTOR dependent pathway.

The drs gene is an apoptosis-inducing tumor suppressor. By using drs-knockout (KO) mouse embryonic fibroblasts (MEFs), we showed that drs is involved in the host defense against viral infection. In drs-KO MEFs infected with vesicular stomatitis virus, the viral replication and protein synthesis were markedly enhanced without the upregulation of the cellular protein synthesis. Phosphorylation of S6K, S6, 4EBP1 and TSC2 proteins was closely correlated with the enhanced viral replication in drs-KO MEFs. Drs protein could associate with stress-inducible GADD34 to form a complex with TSC1/2, which suppresses mTOR activity. These findings indicate that Drs suppresses viral replication via mTOR-dependent pathway.