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K Tsuneyama

Publications and source records attributed to K Tsuneyama.

51 records · Page 3Linked to original sources
PubMed1997

Clinicopathological study of primary biliary cirrhosis negative for antimitochondrial antibodies.

Primary biliary cirrhosis (PBC) is characterized by the occurrence of antimitochondrial antibodies (AMA) and the progressive destruction of intrahepatic bile ducts, followed by biliary cirrhosis. However, there are about 5% of PBC patients who show clinicopathological features of PBC but are negative for AMA. In this study, clinicopathological features, as well as antibody reactivity against recombinant (r)-mitochondrial polypeptides, were examined in 30 AMA negative PBC patients and 38 AMA positive PBC patients, in whom the presence of AMA had been determined by indirect immunofluorescence (IF). There were few differences in the clinical and serological features between both groups. Histopathologic features, including staging, bile duct lesions and granuloma, were also similar in both groups. Among the 30 IF-tested AMA negative patients, 29 were also negative against beef heart mitochondrial proteins, but 24 reacted to one or more of the following r-polypeptides, as determined by immunoblotting: E1 alpha of pyruvate dehydrogenase complex, the E2 subunit of pyruvate dehydrogenase complex, and the branched-chain 2-oxo-acid dehydrogenase complex. The remaining six AMA-negative patients were asymptomatic, and histologically resembled having stage 1 of the disease, with relatively mild lymphocytic piecemeal necrosis. One case was positive for anti-smooth muscle antibody. The other clinicopathological features of these patients were similar to those of other AMA negative patients. The present study found that a majority of the AMA-negative patients fulfilling other clinicopathological criteria of PBC, had features similar to the AMA-positive PBC patients, and that a majority of IF AMA-negative patients were positive for r-polypeptides of the 2-oxo-acid dehydrogenase complex. It seems that nearly all the AMA negative patients possess a broad spectrum of antibody profile of AMA, in addition to clinicopathological and serological features.

Adult↗
PubMed1997

A comparative analysis of the murine thymic microenvironment in normal, autoimmune, and immunodeficiency states.

It is widely accepted that the thymic microenvironment regulates normal thymopoiesis through a highly coordinated and complex series of cellular and cytokine interactions. A direct corollary of this is that abnormalities within the microenvironment could be of etiologic significance in T-cell-based diseases. Our laboratory has developed a large panel of monoclonal antibodies (mAbs) that react specifically with epithelial or nonepithelial markers in the thymus. We have taken advantage of these reagents to characterize the thymic microenvironment of several genetic strains of mice, including BALB/cJ, C57BL/6J, NZB/BlnJ, SM/J, NOD/Ltz, NOD/Ltz-scid/sz, C57BL/6J-Hcphme/Hcphme, and ALY/NscJcl-aly/aly mice, and littermate control animals. We report herein that control mice, including strains of several backgrounds, have a very consistent phenotypic profile with this panel of monoclonal antibodies, including reactivity with thymic epithelial cells in the cortex, the medulla and the corticomedullary junction, and the extracellular matrix. In contrast, the disease-prone strains studied have unique, abnormal staining of thymic cortex and medulla at both the structural and cellular levels. These phenotypic data suggest that abnormalities in interactions between developing thymocytes and stromal cells characterize disease-prone mice.

Animals↗
PubMed1997

Primary biliary cirrhosis an epithelitis: evidence of abnormal salivary gland immunohistochemistry.

Primary biliary cirrhosis (PBC) is an autoimmune liver disease of unknown etiology. Nearly 93% of patients with PBC exhibit evidence of focal sialoadenitis. In an earlier study, we reported evidence of aberrant expression of PDC-E2, or a mimeotope, in the salivary glands of patients with PBC that had Sjogren's syndrome. At the time of the previous study, data was not yet available regarding patients with PBC without sicca complaints. Therefore, to investigate the extent of salivary gland involvement in PBC, we collected lip biopsy sections from 9 PBC patients diagnosed as PBC by liver biopsy, without clinical or histologic features of Sjogren's syndrome and 9 PBC patients with established Sjogren's syndrome. Using immunohistochemical staining with both a murine monoclonal antibody. C355.1, and a human combinatorial antibody, SP4, we examined the ducts of these salivary glands for the presence of the characteristic aberrant staining pattern found in patients with PBC. We report that 6/9 PBC patients fulfilling established Sjogren's syndrome criteria and 6/9 PBC patients lacking features of Sjogren's syndrome showed intense staining of the ductal epithelial cells of the salivary gland. These data suggest that the PBC-specific antigen recognized by C355.1 and SP4 in bile duct epithelial cells is expressed aberrantly in the salivary gland in 66% of patients with PBC, independent of Sjogren's syndrome. This finding suggests a common disease process in these two tissues. Further, expression of this molecule may be an early marker of salivary gland involvement in patients with PBC.

Animals↗
PubMed1996

Random phage mimotopes recognized by monoclonal antibodies against the pyruvate dehydrogenase complex-E2 (PDC-E2).

Dihydrolipoamide acetyltransferase, the E2 component of the pyruvate dehydrogenase complex (PDC-E2), is the autoantigen most commonly recognized by autoantibodies in primary biliary cirrhosis (PBC). We identified a peptide mimotope(s) of PDC-E2 by screening a phage-epitope library expressing random dodecapeptides in the pIII coat protein of fd phage using C355.1, a murine monoclonal antibody (mAb) that recognizes a conformation-dependent epitope in the inner lipoyl domain of PDC-E2 and uniquely stains the apical region of bile duct epithelium (BDE) only in patients with PBC. Eight different sequences were identified in 36 phage clones. WMSYPDRTLRTS was present in 29 clones; WESYPFRVGTSL, APKTYVSVSGMV, LTYVSLQGRQGH, LDYVPLKHRHRH, AALWGVKVRHVS, KVLNRIMAGVRH and GNVALVSSRVNA were singly represented. Three common amino acid motifs (W-SYP, TYVS, and VRH) were shared among all peptide sequences. Competitive inhibition of the immunohistochemical staining of PBC BDE was performed by incubating the peptides WMSYPDRTLRTS, WESYPDRTLRTS, APKTYVSVSGMV, and AALWGVKVRHVS with either C355.1 or a second PDC-E2-specific mAb, C150.1. Both mAbs were originally generated to PDC-E2 but map to distinct regions of PDC-E2. Two of the peptides, although selected by reaction with C355.1, strongly inhibited the staining of BDE by C150.1, whereas the peptide APKTYVSVSGMV consistently inhibited the staining of C355.1 on biliary duct epithelium more strongly than the typical mitochondrial staining of hepatocytes. Rabbit sera raised against the peptide WMSYPDRTLRTS stained BDE of livers and isolated bile duct epithelial cells of PBC patients more intensively than controls. The rabbit sera stained all size ducts in normals, but only small/medium-sized ductules in PBC livers. These studies provide evidence that the antigen present in BDE is a molecular mimic of PDC-E2, and not PDC-E2 itself.

Amino Acid Sequence↗
PubMed1996

Granulomatous cholangitis in chronic hepatitis C: a new diagnostic problem in liver pathology.

A case of chronic hepatitis C at the pre-cirrhotic stage complicated with hepatocellular carcinoma is reported. The patient, a 64 year old female, showed elevated levels of serum alkaline phosphatase and immunoglobulin M. Antimitochondrial antibodies were negative by indirect immunofluorescence. Western blotting using beef heart mitochondria and recombinant polypeptides coding for mitochondrial antigens revealed that the patient's serum was positive only for the E2-subunit of the branched chain ketoacid dehydrogenase complex. In the non-neoplastic liver, chronic non-suppurative cholangitis surrounded by epithelioid granuloma, resembling the granulomatous destructive cholangitis of primary biliary cirrhosis, was found. The damaged bile ducts were immunohistochemically minimally positive or ambiguous for HLA-DR, and their expression of the E2-subunit of the pyruvate dehydrogenase complex E2 (PDC-E2) was diffuse or granular, and not typical of primary biliary cirrhosis. There was no bile duct loss, and orcein-positive copper binding granules reflecting chronic cholestasis were negative in periportal hepatocytes. The overall features in this case were consistent with primary biliary cirrhosis presenting an infrequent profile of antimitochondrial antibodies and atypical expression of HLA-DR and PDC-E2 on biliary epithelial cells, with late superimposition on chronic hepatitis C. However, it is also possible that this is a case of chronic hepatitis C with hepatitis-associated bile duct damage accompanied by granulomatous reaction. Either way, this case raises new diagnostic issues in the differential diagnosis of chronic liver diseases presented with granulomatous cholangitis.

Aged↗
PubMed1995

Immunohistochemical analysis of adhesion molecules in the micro-environment of portal tracts in relation to aberrant expression of PDC-E2 and HLA-DR on the bile ducts in primary biliary cirrhosis.

We have examined immunohistochemically the expression of adhesion molecules in the micro-environment of portal tracts and their relationship to the expression of the pyruvate dehydrogenase E2 complex (PDC-E2) and HLA-DR in liver biopsy specimens. Ten cases of primary biliary cirrhosis (PBC) and 19 controls were examined, including four cases of extrahepatic biliary obstruction, six of chronic viral hepatitis, and nine normal livers. In PBC, the damaged small bile ducts demonstrated an increased expression of PDC-E2 and an aberrant expression of HLA-DR; about half of these damaged bile ducts also expressed intercellular adhesion molecules (ICAM)-1 and a few expressed vascular adhesion molecule (VCAM)-1. In addition, lymphocyte function-associated antigen (LFA)-1 and very late antigen (VLA)-4 were expressed on infiltrating lymphocytes around these bile ducts. In contrast, in control livers, these alterations in antigen expression on the bile ducts were either not observed or were only focal and weak, when present. These findings suggest that ICAM-1/LFA-1 and also VCAM-1/VLA-4 linkages between the damaged bile ducts and lymphocytes may facilitate antigen-specific reactions such as the presentation of antigens, possibly PDC-E2, to the periductal lymphocytes in PBC. ICAM-1, VCAM-1, and E-selectin were strongly expressed on the endothelial cells of some vessels in the portal tracts in PBC, suggesting the facilitation of the recruitment of lymphocytes around the bile ducts of PBC. VCAM-1, a member of the immunoglobulin superfamily, has not hitherto been reported on bile ducts.

Adult↗
PubMed1995

Biliary epithelial expression of pyruvate dehydrogenase complex in primary biliary cirrhosis: an immunohistochemical and immunoelectron microscopic study.

It has been reported recently that there is a unique distribution of the E2 subunit of the pyruvate dehydrogenase complex (PDC-E2) on biliary epithelial cells in patients with primary biliary cirrhosis (PBC) but not primary sclerosing cholangitis. This distribution has been demonstrated using a mouse monoclonal antibody, coined C355.1. The epitope recognized by C355.1 is near the lipoic acid binding site of PDC-E2. C355.1 inhibits PDC-E2 activity in vitro and, unlike a panel of other monoclonal antibodies against different regions of PDC-E2, appears to bind not only to mitochondria but also to a unique antigen expressed predominantly on the luminal side of biliary epithelial cells in PBC. We have extended these observations by studying the subcellular reactivity of C355.1 using postembedding immunoelectron microscopy on the intrahepatic small bile ducts of PBC livers, extrahepatic biliary obstruction (EBO) livers, and normal livers. We report that the reactivity of C355.1 can be classified into two categories. The first category is characterized by small foci of reaction products that were randomly dispersed in cytoplasm, particularly in supranuclear areas; the ultrastructural characterization of these foci was impossible to define but was similar in PBC and EBO. However, of particular interest was the second category of reactivity, which was characterized by deposition of reaction products around the biliary lumen, including microvilli and adjacent subluminal ectoplasm and secretory substances in the biliary lumen. This staining pattern was frequent in PBC livers, only occasionally evident in EBO livers, and not found in normal livers. These data further define and highlight the unique subcellular distribution of PDC-E2 around the biliary lumen in PBC livers and suggest that this abnormality is related to the pathogenesis of bile duct lesions.

Bile Ducts, Intrahepatic↗
PubMed1995

Abnormal expression of the E2 component of the pyruvate dehydrogenase complex on the luminal surface of biliary epithelium occurs before major histocompatibility complex class II and BB1/B7 expression.

Primary biliary cirrhosis (PBC) is a chronic autoimmune liver disease characterized histologically by nonsuppurative destructive cholangitis. Sera from patients with PBC react with a series of intramitochondrial enzymes with the immunodominant response directed against the E2 component of the pyruvate dehydrogenase complex (PDC-E2). Recently, using tissue sections of late-stage PBC, we showed that there is increased expression in biliary epithelial cells of patients with PDC-E2 or a molecule cross-reactive with PDC-E2. Previous work has shown that biliary epithelial cells of patients with PBC express an increased amount of class II. To address the sequence of events in the evolution of PBC, we have focused our attention in this study on early biliary epithelial lesions. In particular, we have studied the liver of 22 female patients with PBC that was diagnosed as either stage I or stage II using both a mouse monoclonal antibody that has reactivity similar to human autoantibodies as well as a human Fab combinatorial prepared from the lymph node of a PBC patient. Tissues were simultaneously stained using antibodies to PDC-E2, class II, and BB1/B7. As a positive control, tissues from late-stage PBC were studied concurrently. By determining the order of expression among the three molecules, PDC-E2, class II, and BB1/B7, we report that the expression of PDC-E2 or a PDC-E2-like molecule on biliary duct epithelium of patients with PBC precedes the expression of BB1/B7 and major histocompatibility complex (MHC) class II molecules. The alteration of an autoantigen in biliary duct epithelium may be the earliest lesion in PBC.

Adult↗
PubMed1995

Abnormal expression of PDC-E2 on the apical surface of biliary epithelial cells in patients with antimitochondrial antibody-negative primary biliary cirrhosis.

The presence of antimitochondrial antibodies (AMA) is a major criterion for the diagnosis of primary biliary cirrhosis (PBC). Although it is not clear that AMA are involved in the pathogenesis of the disease, the study of these autoantibodies has enabled much information to be accumulated about the specificity of this response. The autoantigens have been identified as components of a functionally related enzyme family, the 2-oxo-acid-dehydrogenase complex. Within this complex, pyruvate dehydrogenase E2 subunit (PDC-E2) has been determined to be the immunodominant autoantigen. Using a panel of mouse monoclonal antibodies and human combinatorial autoantibodies, it has been demonstrated that patients with PBC, but not controls, have an abnormal expression of either PDC-E2 or a cross-reacting molecule in the apical region of biliary epithelium. Others have shown a similar reaction using rabbit sera directed to PDC-E2. Our previous studies have concentrated on AMA-positive patients. In this study, the presence of PDC-E2, class II, immunoglobulin (Ig) A, and B7/BB1 in the bile duct epithelial cells of AMA-positive as well as AMA-negative patients is addressed. Most patients with AMA-negative PBC (seven of nine) react in a fashion similar to AMA-positive patients with intense staining of the apical region of the bile duct epithelial cells of "PDC-E2," increased IgA expression, and little major histocompatibility complex (MHC) class II staining in the early-stage patients. Interestingly, the two AMA-negative patients that did not express PDC-E2 on the apical side of their biliary epithelium had anticentromere antibodies and Sjögren's syndrome.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Human combinatorial autoantibodies and mouse monoclonal antibodies to PDC-E2 produce abnormal apical staining of salivary glands in patients with coexistent primary biliary cirrhosis and Sjögren's syndrome.

An increase in the incidence of Sjögren's syndrome in patients with primary biliary cirrhosis has been noted. Indeed, primary biliary cirrhosis has been described as a ductal disease with involvement not only of the biliary tract but of epithelial ductal cells in other organs. We have previously reported the development of a panel of mouse monoclonal antibodies directed at PDC-E2, the major autoantigen of primary biliary cirrhosis. One such antibody, C355.1, but none of the other monoclonal antibodies, reacted not only with mitochondria but also with the apical region of biliary epithelium of patients with primary biliary cirrhosis but not in similar specimens from patients with other liver disease or normal human liver. In addition, we have reported the development of human combinatorial antibodies specific for PDC-E2; these reagents also reacted uniquely with the biliary epithelium of patients with primary biliary cirrhosis. In this paper, we have performed a similar study and have compared the staining of monoclonal antibody C355.1 and a human combinatorial antibody, SP4, with control monoclonal antibodies with respect to their reactivity of salivary glands in 9 patients with primary biliary cirrhosis associated with Sjögren's syndrome, 11 patients with Sjögren's syndrome alone and 7 control patients. Interestingly, the apical region of the salivary gland epithelial cells of approximately 50% of patients with coexisting primary biliary cirrhosis and Sjögren's syndrome had a staining pattern similar to that seen in primary biliary cirrhosis biliary epithelium. In contrast, we did not observe this reactivity in any patient with Sjögren's syndrome alone or in any control patient.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Hepatic inflammatory pseudotumor associated with chronic cholangitis: report of three cases.

We present three cases of hepatic inflammatory pseudotumor associated with chronic cholangitis. In these three cases the inflammatory pseudotumor was solitary, was present in the hepatic hilar region, and had been misdiagnosed as cholangiocarcinoma by imaging modalities and/or gross pathologic examination. Hilar bile ducts were embedded within the tumor. Histologically, these "tumors" consisted of an 2ad-mixed proliferation of lymphocytes, plasma cells, and fibroblasts with variable hyaline fibrosis. The phenotypes of lymphocytes and plasma cells within the tumor were immunohistochemically heterogeneous. Bile ducts and peribiliary glands embedded within these tumors showed nonspecific fibrosis and inflammation, and inflammatory changes of the bile ducts were imperceptibly merged with those of the inflammatory tumor, raising the possibility that these tumors may have arisen in relation to cholangitis. The bile ducts adjacent to the tumor also showed similar but milder nonspecific inflammatory changes. The pathogenesis of cholangitis was unknown in two cases and was speculated to be due to fungal infection in the remaining case. These cases may indicate that biliary tract disease(s) should be explored as the etiology of hepatic inflammatory pseudotumor.

Aged↗
PubMed1994

Hepatitic bile duct injuries in chronic hepatitis C: histopathologic and immunohistochemical studies.

Interlobular bile ducts are reported to be damaged in viral hepatitis. Such damages are called hepatitic duct injuries and mimic chronic nonsuppurative destructive cholangitis of primary biliary cirrhosis. In this study, hepatitic bile duct injuries were evaluated histopathologically and immunohistochemically in 149 needle liver biopsy specimens from patients with chronic hepatitis C and compared immunohistochemically with primary biliary cirrhosis. Fifty-one of the needle biopsies from patients with chronic hepatitis C (34.2%) showed hepatitic bile duct injuries which were distributed focally in the liver and showed variable epithelial damages such as cytoplasmic swelling, vacuolation and acidophilia, nuclear pleomorphism, and loss of nuclear polarity. Some of the injured bile ducts were embedded within lymphoid aggregates, whereas others were surrounded by lymphocytes as well as other inflammatory cells to varied degrees. The majority of lymphoid cells around hepatitic bile duct injury were B- and T-cells mixed in various proportions, and activated T-cells were occasionally found within the biliary epithelial layer. Histopathologic and serial section studies disclosed that bile duct loss was rare in chronic hepatitis C. Statistical analysis revealed that advancement of chronic hepatitis and the degree of necroinflammatory processes of the liver, particularly in the portal tracts, were positively correlated with the occurrence of hepatitic bile duct injuries. Immunohistochemical studies demonstrated that, whereas strong ectopic expression of HLA-DR and enhanced expression of HLA-A,B,C, and pyruvate dehydrogenase E2-complex in biliary epithelial cells were frequently observed in chronic nonsuppurative destructive cholangitis of primary biliary cirrhosis, such unusual expressions were generally absent or mild, even if present, in bile duct injuries in chronic hepatitis C.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗