Expression Of Ley Antigen Research Articles

Quantum changes in Helicobacter pylori gene expression accompany host-adaptation.

Helicobacter pylori is a highly successful gastric pathogen. High genomic plasticity allows its adaptation to changing host environments. Complete genomes of H. pylori clinical isolate UM032 and its mice-adapted serial derivatives 298 and 299, generated using both PacBio RS and Illumina MiSeq sequencing technologies, were compared to identify novel elements responsible for host-adaptation. The acquisition of a jhp0562-like allele, which encodes for a galactosyltransferase, was identified in the mice-adapted strains. Our analysis implies a new β-1,4-galactosyltransferase role for this enzyme, essential for Ley antigen expression. Intragenomic recombination between babA and babB genes was also observed. Further, we expanded on the list of candidate genes whose expression patterns have been mediated by upstream homopolymer-length alterations to facilitate host adaption. Importantly, greater than four-fold reduction of mRNA levels was demonstrated in five genes. Among the down-regulated genes, three encode for outer membrane proteins, including BabA, BabB and HopD. As expected, a substantial reduction in BabA protein abundance was detected in mice-adapted strains 298 and 299 via Western analysis. Our results suggest that the expression of Ley antigen and reduced outer membrane protein expressions may facilitate H. pylori colonisation of mouse gastric epithelium.

Clinical Evaluation of BR96 sFv-PE40 Immunotoxin Therapy in Canine Models of Spontaneously Occurring Invasive Carcinoma

The immunotoxin BR96 sFv-PE40 is an effective antitumor agent against human breast and lung carcinoma xenografts in rodents. This study was designed to (a) determine the frequency with which canine carcinoma cells express Lewis(y) (Le(y)) antigen, thereby identifying canine carcinoma types suitable for the clinical evaluation of BR96 sFv-PE40, and (b) determine the safety and efficacy of BR96 sFv-PE40 in a canine model of spontaneously occurring cancers for investigation of targeted therapy. Carcinoma tissue samples were obtained from client-owned dogs presented for medical care. The tissues were assessed for Le(y) antigen expression using immunohistochemical methods. Dogs with tumors expressing Le(y) antigen were offered enrollment in a clinical trial to receive twice-weekly infusions of 4 to 12 mg/m(2) BR96 sFv-PE40. Clinical toxicity and response data were assessed at each treatment. Twenty-two of 61 carcinomas evaluated were positive for Le(y) expression, including mammary, prostate, lung, and rectal carcinomas, and 12 dogs were enrolled in the clinical trial. The primary side effect was transient emesis. Partial responses or disease stabilization were noted in dogs with inflammatory mammary, bronchogenic, rectal, and tonsillar carcinoma. At least nine of the dogs developed antibodies to the immunotoxin after two to five infusions. Although development of anti-BR96 sFv-PE40 antibodies limited the long-term effectiveness of this immunotoxin in dogs, rapid clinical responses in several aggressive canine carcinomas suggest the immunotoxin has utility for treatment of certain naturally occurring tumors and that its clinical evaluation for treatment of similar human carcinomas is warranted.

Induction of tumour differentiation and apoptosis and LeY antigen expression in treatment with differentiation-inducing agent, vesnarinone, of a patient with salivary adenoid cystic carcinoma.

A patient with locally-advanced submandibular adenoid cystic carcinoma with poorly differentiated solid type, was treated with differentiation-inducing agent, vesnarinone, per os at a dose of 60 mg/day daily for 8 weeks. The vesnarinone administration caused marked regression of the tumour. In addition to conversion into the well-differentiated tubular type from the poorly differentiated solid type, the induction of apoptosis and LeY antigen was observed in the treated tumour. These findings indicate that vesnarinone might be a useful therapeutic agent for treatment of salivary cancer. Since we found the new expression of LeY antigen in the well-differentiated tubular lesion in the salivary adenoid cystic carcinoma treated with vesnarinone, we examined the LeY antigen expression in relation to tumour differentiation in five cases of salivary adenoid cystic carcinoma. Consequently, tissue sections from all of the adenoid cystic carcinoma examined showed no positive LeY staining, except for some areas in the tumour lesion with the tubular pattern including the histologically normal-appearing tissue adjacent to the tumour tissue. These findings suggest that there is the intimate relationship between the LeY antigen expression and tumour differentiation in human salivary adenoid cystic carcinoma.

白板症の免疫組織化学的検討 上皮異形成とＬｅ｀ｙ´抗原およびＰ５３蛋白発現との関連

The correlation of epithelial dysplasia with the expression of Lewisy (Ley) antigen and P53 protein was evaluated in oral leukoplakia. Changes in the expression of Ley antigen, P53 protein, and proliferating cell nuclear antigen (PCNA) were examined immunohistochemically in 30 cases of tongue leukoplakia with epithelial dysplasia (mild dysplasia: 11 cases, moderate dysplasia: 10 cases, and severe dysplasia: 9 cases). In addition, the expressions of these molecules in normal tongue epithelia and leukoplakia without epithelial dysplasia were also investigated.The results revealed that Ley antigen was distributed throughout the epithelium except for the basal cell layer in normal epithelium, whereas in leukoplakia it was localized only in the superficial epithelium. P53 protein and PCNA appeared chiefly in the basal cell layer in normal epithelium, while they were more widely distributed in leukoplakia. The positive rate of Ley antigen decreased with the grade of epithelial dysplasia. In contrast, both P53 protein and PCNA positivity increased with the grade of epithelial dysplasia. Specifically, significant changes in the positivity of Ley antigen and P53 protein were observed in leukoplakia, when epithelial dysplasia progressed from mild to moderate dysplasia.These results suggest that mutations of the p53 gene and alterations of cell surface carbohydrates may occur in the early stage at which epithelial dysplasia progress from mild to moderate.

Apoptosis as a mechanism of skin renewal: Le(y)-antigen expression is involved in an early event of a cell's commitment to apoptosis.

Skin renewal is a typical example of the active participation of a cell in its own death process. Cells arising from mitotic activity in the stratum germinativum of the epidermis continuously migrate upwards to the stratum corneum, where dead cells are eventually desquamated. Recent studies have suggested that apoptosis is involved in the dynamic process of skin renewal. However, this still remains to be further elucidated. In this paper, we investigated the involvement of apoptosis in the skin renewal process. Changes in the morphology of cells in different epidermal layers were compared with histochemical analyses of the extent of DNA fragmentation, as determined by nick end-labelling, and of the reactivities to a monoclonal antibody directed to Le(y)-antigen, difucosylated type 2 chain determinant, which has a close association with apoptosis, and to a monoclonal antibody directed to the proliferating cell nuclear antigen. The results show that apoptosis proceeds concomitantly with cell movement in the epidermis. It seems likely that commitment of a cell to death by apoptosis occurs in the epidermal tissue immediately after completion of cell proliferation, and that Le(y)-antigen expression may be involved in the entire apoptotic process including this early event.

Induction of Differentiation and Apoptosis, and Ley Antigen Expression by Treatment with 3,4-Dihydro-6-(4-(3,4-Dimethoxybenzoyl)-1-Piperazinyl)-2(1H)-Quinolinone (Vesnarinone) in a Human Salivary Cancer Cell Line.

It has been found that 3, 4-dihydro-6-[4-(3, 4-dimethoxybenzoyl)-1-piperazinyl]-2(1H)-quinolinone (Vesnarinone), a newly synthesized positive inotropic agent, has differentiation-inducing activity against various human solid tumor cells.In the present study, we examined the effect of vesnarinone on the differentiation, apoptosis and Ley antigen expression of human adenoid squamous carcinoma-forming cell line TYS derived from a minor salivary gland, which was grown in culture. Cultivation of TYS cells in the presence of vesnarinone (10-50μg/ml) resulted in the formation of secretory granules with salivary amylase in the cytoplasm as well as in the induction of apoptosis in the cells detached from the plastic surface and floated in the medium, in which intracellular calcium levels were significantly increased. On the other hand, appearance of large cells with numerous vacuoles having salivary amylase was observed in the attached cells, in which apoptotic change was not detected. Ley expression was detected in the cytoplasmic membrane of cultured TYS cells, while translocation of Ley antigen from cytoplasmic membrane to perinuclear area was observed in the attached TYS cells treated with vesnarinone. Moreover, it has been found by immunoblot analysis of TYS cell membrane proteins and cytosolic proteins that the Ley antigen in TYS cells forms a complex with 40kd protein and the Ley complex moves from cytoplasmic membrane to perinuclear area in the attached TYS cells undergoing acinar cell differentiation, but not apoptosis. Thus, it can be considered that the translocation of Ley antigen in vesnarinone-treated TYS cells may be associated with the cellular differentiation, rather than with the induction of apoptosis.

抗Ｌｅ｀ｙ´抗体を用いたＲＡの滑膜・軟骨組織におけるアポトーシスの発現と病的意義

Ley antigen expression is assumed to be a predisposing marker for apoptosis. In this study we semi-quantitatively examined apoptosis of cells in joint tissues, such as synovia, cartilage and bone in rheumatoid arthritis (RA) by means of an immuno-histochemical technique with anti-Ley antigen antibodies.In synovia of patients with trauma or osteoarthritis (OA), only a few inflammatory cells were positive for Ley, while in RA, inflammatory cells, mainly neutrophils, were strongly Ley positive. Furthermore capillary endothelial cells were also Ley positive.In RA the number of Ley positive inflammatory cells increased with the progression of inflammation, and decreased with the progression of fibrosis. The number of capillaries with Ley positive endothelial cells, revealed same tendency. We concluded therefore that apoptosis is related to the degree of inflammation in RA.In bone and cartilage of patients with RA, some chondrocytes neighboring granulations were Ley positive, but there were no positive cells in patients with OA. For this reason we propose that apoptosis of chondrocytes may be triggering to cartilagenous destruction as well as production of proteinases in RA.

Lymphocyte membrane modifications induced by HIV infection.

Novel carbohydrate antigen expressions were observed on T lymphocytes from HIV infected patients using flowcytometric analysis with four mAbs; BM-1, ACFH-18, FH-2 and C-6. These carbohydrate antigens were also expressed on oncogenic transformed cells but were either not expressed or were weakly expressed in lymphocyte populations from healthy subjects. A dramatic change in glycosylation was induced on CD8+T cells from HIV infected patients. The glycosylation change correlated with the progression of the disease. The incidence of Ley antigen expression on CD8+T cells increased as the disease progressed with the ongoing impairment of immune function. The phenotype change that occurred with Ley antigen expression might reflect the abnormal activation of T lymphocytes of some specific, but unknown, population of CD8+T cells. Thus, carbohydrate changes on the cell surface may induce immunological abnormality and accelerate the damage within the CD4+T cell subset, resulting in an impairment of the antigen specific immune system.

The relationship between LeY antigen and the therapeutic efficacy of interferon in chronic hepatitis C.

The expression of LeY antigen (Fuc alpha 1-->2Gal beta 1-->4 [Fuc alpha-->3] GlcNAc beta 1-->R), recognized by the monoclonal antibody BM-1, was studied in peripheral blood T-lymphocyte subpopulations in patients with viral hepatitis, and in liver tissue of patients with acute viral hepatitis. The relationship between the expression of LeY antigen on peripheral blood T-lymphocytes and the effects of interferon (IFN) therapy for chronic hepatitis type C were also evaluated. LeY antigen is not markedly expressed in B or T-lymphocytes of healthy individuals. However, it was strongly expressed in CD8 and CD4 T-lymphocytes in patients with viral hepatitis. In the acute phase of acute viral hepatitis, the expression of LeY antigen was more markedly expressed on peripheral CD8 T-lymphocytes than on CD4 T-lymphocytes. In chronic hepatitis type B and type C, it was significantly expressed more often on CD4 T-lymphocytes. In the liver tissues of patients with acute viral hepatitis, LeY antigen was expressed on hepatocytes and infiltrating lymphocytes. IFN therapy for chronic active hepatitis type C proved most effective when LeY antigen was more markedly expressed on the patient's CD4 and CD8 peripheral blood T-lymphocytes before treatment. Further studies are needed to clarify the relationship between the mechanisms of hepatic cell injury and LeY antigen.

Immunohistochemical study of carbohydrate antigen expression in gastric carcinoma.

The expression of carbohydrate antigens in malignant and non-malignant gastric mucosa was studied immunohistochemically using the monoclonal antibody AH6 directed to Ley antigen, FH2 directed to Lex antigen, and FH6 directed to sialyl-Lex antigen. Formalin-fixed gastric tissue resected from 54 patients with gastric cancer and 20 patients with gastric ulcer were tested. The incidence of positive cases in gastric cancer patients with each antibody was as follows: AH6;85%, FH2;74%, FH6;74%. The Lex antigen was expressed in 81.5% of cases histologically classified as undifferentiated type, and 66.7% of cases classified as differentiated type. It was expressed in a higher incidence in early stage cancer (93.3%) than in advanced stage cancer (66.7%). Sialyl-Lex antigen was detected in more cases of differentiated type (88.9%) than in those of undifferentiated type (59.3%), whereas none of 8 early cancers of undifferentiated type expressed the antigen. The incidence of the expression of Ley antigen did not differ in relation to histological type or invasiveness. Lex and Ley antigens were detected in noncancerous gastric epithelium. Sialyl-Lex antigen was not detected in the normal fundic gland region. These results demonstrate that Lex antigen may be a differentiation-associated antigen, and sialyl-Lex antigen might be useful as a marker of differentiated cancer and an indication for invasion of undifferentiated cancer.

Expression of Ley antigen in human immunodeficiency virus-infected human T cell lines and in peripheral lymphocytes of patients with acquired immune deficiency syndrome (AIDS) and AIDS-related complex (ARC).

Ley determinant (Fuc alpha 1----2Gal beta 1----4[Fuc alpha 1----3]GlcNAc beta 1----R) defined by mAb BM-1 is highly expressed in human immunodeficiency virus (HIV)-infected T cell lines and in CD3+ peripheral mature T cells of patients with acquired immune deficiency syndrome (AIDS) or with AIDS-related complex (ARC). Ley expression increased greatly in the CD3+ population in the advanced stage of AIDS when the CD4+ population decreased greatly. Six other carbohydrate antigens tested by their respective mAbs were not detected in these same cells. None of the carbohydrate antigens tested by the seven mAbs used in this study were found in noninfected T cell lines and in normal peripheral blood lymphocytes.