Monoclonal antibodies against synthesized short peptides corresponding to human AA amyloid protein

Monoclonal antibodies (McAbs) were raised against the synthesized short peptides corresponding to 37-47 residues in amino acid sequence of human AA protein. The McAbs reacted immunohistochemically to amyloid tissues from cow, mouse, swan, and human AA amyloidosis. We concluded that the McAbs were useful for identification of AA type amyloidosis of various species, and that the 37-47 residues were effective antigenic sites in AA protein.     

Regulation of Th2 cell differentiation by mel-18, a mammalian polycomb group gene

Polycomb group (PcG) gene products regulate homeobox gene expression in Drosophila and vertebrates and also cell cycle progression of immature lymphocytes. In a gene-disrupted mouse for polycomb group gene mel-18, mature peripheral T cells exhibited normal anti-TCR-induced proliferation; however, the production of Th2 cytokines (IL-4, IL-5, and IL-13) was significantly reduced, whereas production of IFNgamma was modestly enhanced. Th2 cell differentiation was impaired, and the defect was associated with decreased levels in demethylation of the IL-4 gene. Significantly, reduced GATA3 induction was demonstrated. In vivo antigen-induced IgG1 production and Nippostrongylus brasiliensis-induced eosinophilia were significantly affected, reflecting the deficit in Th2 cell differentiation. Thus, the PcG gene products play a critical role in the control of Th2 cell differentiation and Th2-dependent immune responses.     

CD69-null mice protected from arthritis induced with anti-type II collagen antibodies

CD69, known as an early activation marker antigen on T and B cells, is also expressed on platelets and activated neutrophils, suggesting certain roles in inflammatory diseases. In order to address the role of CD69 in the pathogenesis of arthritis, we established CD69-null mice. CD69-null mice displayed a markedly attenuated arthritic inflammatory response when injected with anti-type II collagen antibodies. Cell transfer experiments with neutrophils, but not T cells or spleen cells, from wild-type mice into CD69-null mice restored the induction of arthritis. These results indicate a critical role for CD69 in neutrophil function in arthritis induction during the effector phase. Thus, CD69 would be a possible therapeutic target for arthritis in human patients.     

Abnormal accumulation in lipopolysaccharide in biliary epithelial cells of rats with self-filling blind loop

Primary sclerosing cholangitis (PSC) is known to be frequently associated with inflammatory bowel diseases. In a rat with self-filling blind loop (SFBL), a proposed animal model for PSC, hepatobiliary inflammation has previously been demonstrated. In this study, we assessed the involvement of lipopolysaccharide (LPS), a bacterial endotoxin, in the pathogenesis of hepatobiliary inflammation of the SFBL model. The hepatic localization of LPS was examined by immunohistochemistry using an anti-lipid A antibody. The portal blood concentration of LPS was measured by an endotoxin-specific chromogenic Limulus test (Endospecy test). LPS was localized in the biliary epithelial cells (BECs) of rats with SFBL, and the portal blood concentration of LPS was significantly higher than that of sham-operated rats. Development of hepatobiliary inflammation, peribiliary fibrosis, and injury to the intestinal mucosa were histologically confirmed. Constriction in the biliary trees was radiologically demonstrated. These findings suggested that abnormal accumulation of LPS, which may be derived from portal blood, in BECs was involved in the pathogenesis of hepatobiliary inflammation with intestinal injury.     

Cytomegalovirus infections following umbilical cord blood transplantation using reduced intensity conditioning regimens for adult patients.

Cytomegalovirus (CMV) infection is a major complication after allogeneic hematopoietic stem cell transplantation (Allo-HSCT); however, we have little information on the clinical features of CMV reactivation after cord blood transplantation using reduced-intensity regimens (RI-CBT) for adults. We reviewed medical records of 140 patients who underwent RI-CBT at Toranomon Hospital between January 2002 and March 2005. All the patients were monitored for CMV-antigenemia weekly, and, if turned positive, received preemptive foscarnet or ganciclovir. Seventy-seven patients developed positive antigenemia at a median onset of day 35 (range, 4-92) after transplant. Median of the maximal number of CMV pp65-positive cells per 50,000 cells was 22 (range, 1-1806). CMV disease developed in 22 patients on a median of day 35 (range, 15-106); 21 had enterocolitis and 1 had adrenalitis. CMV antigenemia had not been detected in 2 patients, when CMV disease was diagnosed. CMV disease was successfully treated using ganciclovir or foscarnet in 14 patients. The other 8 patients died without improvement of CMV disease. In multivariate analysis, grade II-IV acute graft-versus-host disease was a risk factor of CMV disease (relative risk 3.48, 95% confidential interval 1.47-8.23). CMV reactivation and disease develop early after RI-CBT. CMV enterocolitis may be a common complication after RI-CBT.     

Inhibition of the accumulation of macrophages and the generation of macrophage chemotactic activity by dexamethasone in concanavalin A-induced peritonitis of mice

A delayed-type inflammatory response was evoked in mice using concanavalin A (Con A) as a stimulus, and the effect of various anti-inflammatory agents on the inflammations was examined. The intraperitoneal injection of Con A in the mouse resulted in the marked accumulation of leukocytes, especially macrophages, in the peritoneal cavity between 16 and 48 hr after the injection. Prior to the accumulation of macrophages, the chemotactic activity for macrophages appeared in the peritoneal fluid, and was associated with protein(s) in the molecular weight range from 10000 to 100000 daltons. When the effect of various agents on Con A-induced peritonitis was examined, neither anticomplementary agents (FUT-175 and K-76 COONa), bromophenacyl bromide, nordihydroguaiaretic acid nor indomethacin affected the generation of chemotactic activity and the accumulation of macrophages, suggesting that C5a, prostaglandins and leukotriene B₄ are hardly involved in the Con A-induced macrophage accumulation. On the other hand, dexamethasone suppressed both the generation of chemotactic activity and the accumulation of macrophages. Taking into consideration the observation that the synthesis of macrophage chemotactic factors by mitogen-stimulated lymphocytes is inhibited by glucocorticoids these results suggest that the macrophage chemotactic lymphokines might be involved in the accumulation of macrophages in Con A-induced peritonitis.     

Significance of an insular component in follicular thyroid carcinoma with distant metastasis at initial presentation

Risk factors for distant metastasis were studied in 82 patients with follicular thyroid carcinoma (FTC). Metastases to either the lung or bone existing at the time of presentation were confirmed by I-131 radio-iodine uptake in 10 patients. FTC with an insular component was found in eight patients. Univariate analysis of 14 possible risk factors showed 7 to be statistically significant: insular component, poorly differentiated carcinoma, trabecular component, serum thyroglobulin level before surgery, patient age at the time of presentation, solid component, and vascular invasion (ranked by p values). After further analysis of the interrelation of the factors and of the logistic regression curves, we concluded that presence of an insular component and patient age were the only independent risk factors. Distant metastasis was not detected in any of the 27 patients ≤49 yr old. Among the 55 older patients (≥50 yr old), 5 of the 49 (10%) without an insular component and 5 of the 6 (83%) with an insular component had distant metastasis. The remaining older patient with an insular component but without distant metastasis showed a gradual increase in thyroglobulin levels after total thyroidectomy.     

Simple method for the identification of oxidative fibers in skeletal muscle

Skeletal muscle is composed of several different types of myofiber: slow oxidative (SO), fast glycolytic oxidative and fast glycolytic. However, the classification is usually determined by myosin heavy chain typing rather than by metabolic index. In this study, the oxidative metabolic index was investigated as a possible method of myofiber typing. Myoglobin, which is involved in oxygen transport and storage in myofibers, and mitochondria, which are the central organelles for oxidative metabolism, were studied. High levels of myoglobin and mitochondria are believed to exist in SO fibers, but the current study showed that they are considerably richer in some fast type fibers. As myofiber typing using the oxidative metabolic index is important physiologically, an attempt was made to find a simple method for this purpose. Some mitochondrial proteins have been observed to auto-fluoresce but until now this effect was too faint to detect easily. Owing to the recent advances in cooling charge-coupled device technology, such auto-fluorescence can now be used for myofiber typing, and the simple and rapid method for doing so is reported here.