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Y Beck

Publications and source records attributed to Y Beck.

At least 37 records · Page 2Linked to original sources
PubMed1995

Polymorphism of human minor histocompatibility antigens: T cell recognition of human minor histocompatibility peptides presented by HLA-B35 subtype molecules.

To investigate the polymorphism of human minor histocompatibility (mH) antigens, PBLs from 23 Japanese individuals and 25 German individuals with HLA-B35 were studied by using four human mH antigen-specific, HLA-B35-restricted CTL clones. The CTL clones killed PHA-stimulated PBLs from all 23 Japanese individuals. On the other hand, they killed the PHA-stimulated PBLs from 19 of 25 German individuals and partially killed the PHA-stimulated PBLs from three German individuals (CTL weakly sensitive cell line); those from another three individuals (CTL-resistant cell line) were not killed by the CTL clones. All of three CTL weakly sensitive cell lines carry HLA-B*3503 molecules, whereas the three CTL-resistant cell lines carry HLA-B*3502, B*3507, and B*3508 molecules. The cytotoxicity of the CTL clones for three CTL weakly sensitive cell lines was enhanced by stimulation of human mH peptides isolated from HLA-B*3501 molecules purified from C1R-B*3501 cells. Small amounts of human mH peptides were isolated from B*3503 molecules purified from these three CTL weakly sensitive cell lines. Taken together, these results indicate that weak recognition by the CTL clones of three CTL weakly sensitive cell line results from a small amount of the human mH peptides presented by B*3503 molecules. The CTL-resistant cell line carrying B*3507 loaded with the human mH peptides was killed by four CTL clones, whereas the cell lines carrying B*3502 or B*3508 loaded with the peptides were not. The human mH peptides were not isolated from B*3507 molecules purified from the cell lines expressing this subtype, whereas small amounts of the human mH peptides were isolated from B*3502 and B*3508 molecules purified from the cell lines expressing the subtypes. These results indicate that failure of the CTL recognition of the cell line carrying B*3507 is due to a lack of human mH antigens in this cell line. The failure of the CTL recognition of the cell lines carrying B*3502 and B*3508 is not explained by only the amount of the human mH peptides binding to these B35 subtype molecules because the amount of the human mH peptides eluted from B*3502 and B*3508 molecules purified from the cell lines carrying these B35 subtypes is almost the same as that eluted from B*3503 molecules purified from the cell lines carrying B*3503.(ABSTRACT TRUNCATED AT 400 WORDS)

Amino Acid Sequence↗
PubMed1995

Effect of anti-ICAM-1 and anti-LFA-1 antibodies on rat liver transplantation.

The effect of the anti-cell adhesion molecule antibodies, anti-ICAM-1 (1A29) and anti-LFA-1 (WT1), on rat liver transplantation was investigated. Livers from ACI rats were transplanted into Lewis rats by Kamada's method and during the recipient operation 1A29 1 mg/kg, and WT1 1 mg/kg were administered intravenously to one group of rats (treated group). The survival time of the treated group was significantly longer than that of the untreated group, but permanent unresponsiveness could not be induced. Postmortem examination revealed little histological evidence of acute rejection in treated rats, in which the main cause of death was thought to be chronic rejection.

Animals↗
PubMed1995

Successful resection of a large hepatoblastoma in a young adult: report of a case.

Hepatoblastoma (HB) rarely occurs in adults, and very few cases of successful resection have been documented. We report herein the unusual case of a 22-year-old, otherwise healthy woman with no history of liver disease who presented with upper abdominal pain and hepatomegaly. Tests for hepatitis B virus (HBV) and hepatitis C virus (HCV) were negative, but the AFP was mildly elevated at 77 ng/ml, the normal being < 20. There was no evidence of liver cirrhosis on either the laboratory or histologic examinations. A well-demarcated solid mass of 14 cm in diameter, which was lobulated and partly necrotic, was detected in the liver by computed tomography (CT). The lesion was echogenic on ultrasound, slightly hypodense on CT, and mildly hypervascular on arteriogram. The entire tumor was resected by extensive hepatectomy preserving only the lateral segment and part of the posterior segment of the liver. Histologically, the neoplasm was diagnosed as a pure epithelial HB of the fetal type. Following the operation, the patient has been well and free of recurrence for 38 months, maintaining low alpha-fetoprotein (AFP) levels at around 5 ng/ml. To our knowledge, this is the longest reported survival of an adult following surgical resection of an epithelial HB.

Adult↗
PubMed1993

Expression of human minor histocompatibility antigen on cultured kidney cells.

Incompatibility of human minor histocompatibility (hmH) antigens can induce rejection of grafts in organ transplantation and graft-versus-host reactions in bone marrow transplantation. In spite of their importance in clinical transplantation, hmH antigens are not well studied. Previous studies have demonstrated the expression of hmH antigens on T and B cells, hematopoietic progenitor cells and keratinocytes. We have for the first time demonstrated the expression of hmH antigens on cultured kidney cells using HLA-B35-restricted, hmH antigen-specific cytotoxic T lymphocyte (CTL) clones, which were previously established from a patient who rejected two kidneys from HLA-identical sisters. The CTL clones could not kill cultured kidney cells. Since cultured kidney cells expressed very low levels of HLA class I antigens it was thought that their failure to be killed by the CTL clones was due to lack of expression of HLA-B35 antigens. After induction of class I antigens on cultured kidney cells by interferon-gamma (IFN-gamma), the IFN-gamma-treated cultured kidney cells were killed by the CTL clones. Furthermore, we isolated hmH antigens as peptides from cultured kidney cells after treatment with IFN-gamma. These results indicate that cultured kidney cells express hmH antigens when HLA class I antigen is induced by IFN-gamma and hmH antigens on cultured kidney cells are recognized by T cells as peptides presented by HLA-B35 molecules.

Antibodies, Monoclonal↗
PubMed1992

Spontaneous rupture of hepatocellular carcinoma: an approach with delayed hepatectomy.

Two cirrhotic patients with ruptured hepatocellular carcinoma (HCC), presenting with hemoperitoneum, were successfully treated by elective hepatectomy. Both of these patients, a 67-year-old female and a 76-year-old male, had first been taken to other primary hospitals by ambulance due to hypovolemic shock. They were then found to have a mass of approximately 5 cm in the cirrhotic liver. In the initial management, however, neither any direct hemostasis by surgery nor indirect measures such as transcatheter hepatic arterial embolization were performed in either case. Instead, conservative treatment consisting mainly of fresh blood and plasma transfusions were continued for more than a month until the liver function stabilized. In both hepatectomies, the use of a microwave tissue coagulator resulted in minimal intra-operative blood loss and an appreciably excellent post-operative course. These cases point to the effectiveness of a "wait and see" policy for selected patients with ruptured HCC.

Aged↗
PubMed1991

Recombinant human superoxide dismutases: production and potential therapeutical uses.

In many pathological situations, tissue damage is caused by cellular generation of superoxide free radicals (O2-). These active species are generated during post-ischemic reperfusion of organs, in hyperoxic tissue, during acute and chronic inflammation and during exposure to ionizing radiation. Exogenous superoxide dismutase (SOD) was shown to significantly prevent such damage. The genes for human cytosolic Cu/ZnSOD and mitochondrial MnSOD were cloned and introduced into an E. coli expression system. The proteins were expressed in high yields and purified to homogeneity, yielding pharmaceutical-grade materials. These enzymes were used in a variety of in vivo animal models for the demonstration of their protective effects against oxidative damage. Comparative pharmacokinetic studies in rats have revealed that the half-life of Cu/ZnSOD was 6-10 min., while that of MnSOD was 5-6 hours, thus indicating that MnSOD may be superior to Cu/ZnSOD for the treatment of chronic diseases. Indeed, MnSOD was found to be effective as an anti-inflammatory agent in the rat carrageenan induced paw edema acute inflammation model. Both enzymes were also effective in ameliorating post-irradiation damage in mice exposed to whole-body or localized chest X-ray radiation.

Animals↗