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K Shigeta

Publications and source records attributed to K Shigeta.

At least 37 records · Page 2Linked to original sources
PubMed1993

Preparation of mouse-human chimeric antibody to an embryonic carbohydrate antigen, Lewis Y.

Stage-specific embryonic antigen-1 (SSEA-1) is a well-known carbohydrate antigen that is specifically expressed on the surface of cancer cells as well as embryonic cells. In this study, starting with a previously established hybridoma producing a monoclonal antibody (named H18A) to Lewis Y antigen, which is closely related to SSEA-1, we cloned genomic DNA encoding active variable regions both of heavy and light chains of the antibody. Sequence analysis showed that VH and V kappa genes of H18A were in the VH 7183 family and V kappa C1 family, respectively. A transfected cell line named HC-H18A-7 expressing a recombinant chimeric H18A composed of mouse-derived antigen-binding variable regions and human-derived constant regions was established. The chimeric H18A was purified to homogeneity and shown to bind purified Lewis Y antigen with the same dose-response curve as the original H18A. The chimeric H18A looks more promising for clinical application than the original mouse-derived H18A because its antigenicity is expected to be reduced.

Amino Acid Sequence↗
PubMed1993

Rat liver epidermal growth factor receptors in intrauterine growth retarded and heavy-for-date fetuses.

We recently reported that epidermal growth factor (EGF) levels in the first urine to be voided by intrauterine growth retardation (IUGR) and heavy-for-dates (HFD) infants were lower than control infants (8). In this study, we analyzed EGF receptors to reveal the mechanisms controlling EGF levels. EGF binding to fetal rat liver increased markedly from day 19-21 of gestation. Fetal rats were divided into IUGR, control and HFD groups. EGF binding to the liver in each group was as follows, IUGR; 380 +/- 57 fmol/mg protein, control; 258 +/- 47, and HFD; 545 +/- 112. The binding to IUGR and HFD rat liver was significantly greater than in the control group (p < 0.05). These data suggest that IUGR rats compensate for a lack of EGF by increased receptor expression and that HFD rats consume more EGF and have decreased urinary EGF excretion. These data also suggest that EGF is closely related to fetal growth and may play some important roles in fetal growth.

Animals↗
PubMed1992

Urinary and plasma epidermal growth factor levels are decreased in neonates with intrauterine growth retardation and in their mothers.

Epidermal growth factor (EGF) concentrations in urine and plasma samples collected from pregnant women and neonates were measured by RIA. The EGF concentration of the first voided urine was higher in appropriate-for-date (AFD) neonates (33.9 +/- 23.0 ng/mg creatinine) than in those with intrauterine growth retardation (IUGR; 23.5 +/- 7.7 ng/mg creatinine, p less than 0.05) and heavy-for-date (19.8 +/- 5.2 ng/mg creatinine, p less than 0.05) neonates. The urinary EGF concentration of pregnant women showed no marked changes throughout pregnancy. Urinary EGF concentrations of women with AFD fetuses (45.9 +/- 31.2 ng/mg creatinine) did not differ significantly from those of women with diabetes (39.9 +/- 26.8 ng/mg creatinine) or women with multiple fetuses (44.6 +/- 30.6 ng/mg creatinine). However, women with IUGR fetuses showed lower urinary EGF concentrations (13.8 +/- 7.4 ng/mg creatinine, p less than 0.05) than women with AFD fetuses. Maternal and fetal platelet-poor plasma EGF concentrations at delivery were lower in the IUGR group (mother: 2.62 +/- 0.38 ng/ml, fetus: 2.16 +/- 0.07 ng/ml, respectively, p less than 0.05 and p less than 0.005) than in the AFD group (mother: 3.34 +/- 0.64 ng/ml, fetus: 3.24 +/- 0.93 ng/ml). In the IUGR group, the EGF concentration in fetal blood was always lower than that in maternal blood (p less than 0.05), although the AFD groups showed no such difference. These data suggest that EGF levels are closely related to fetal growth.

Birth Weight↗
PubMed1992

[Improved measurements of anti-L-asparaginase IgG antibody and its clinical applications].

To elucidate the usefulness in prediction of hypersensitive reactions of L-asparaginase (L-asp), anti-L-asp IgG antibody was measured by two kinds of enzyme-linked immunosolvent assay (ELISA) with improved microplate method and original immunobeads method. The correlation coefficient of both methods matched very well (R = 0.949). Nine out of the 10 patients who were treated with L-asp for the first time showed the elevation of the anti L-asp IgG antibody and returned to normal range within 9 months thereafter. Twenty-two out of 26 patients (84.6%) who had ever developed hypersensitive reactions showed the positive anti-L-asp antibody. There was no positive correlation between the anti-L-asp titer and the severity of the hypersensitive reactions. We concluded that the ELISA with microplate was simple and useful methods to determined the anti-L-asp IgG antibody.

Asparaginase↗
PubMed1990

Northern hybridization analysis of VH gene expression in murine monoclonal antibodies directed to cancer-associated ganglioside antigens having various sialic acid linkages.

The expression of the VH genes in 46 murine hybridoma cells that secrete mAb directed to the cancer-associated carbohydrate Ag, especially acidic glycolipids such as gangliosides and sulfated glycoplipids, was analyzed by Northern hybridization of poly(A)+ RNA of hybridoma with cDNA probes for nine VH gene families. Different hybridomas tended to express VH genes of the same family when the cognate Ag had the same or similar carbohydrate structures; i.e., the VH genes of the J558 family (group 1) were preferentially expressed in the mAb directed to various gangliosides that have NeuAc alpha (or NeuGc alpha) 2-3 and/or 2-8 linkage (71%), the most common linkage of sialic acid residues in the gangliosides of higher animals, and the hybridomas directed to sulfated glycolipids also expressed mainly the VH genes of the J558 family (80%). In contrast, the five mAb directed to various gangliosides with NeuAc alpha 2-6 linkage were exclusively encoded by the VH genes of Q52 family (group 2, 100%), and three antibodies directed to gangliosides with a NeuAc alpha 2-9 linkage all expressed genes of J606 family (group 6, 100%). The VH family usage was largely correlated with the linkage of sialic acid residues in the cognate carbohydrate Ag, but was not correlated at all with the difference in the fine specificities toward the core neutral carbohydrate chain, to which the sialic acid residues were attached. These findings suggest that the VH gene family in these anticarbohydrate antibodies is selected, depending primarily on the linkage of the sialic acid residues in carbohydrate Ag; these residues form the immunodominant sugar residue in the respective antigenic determinant.

Animals↗
PubMed1989

Parietal cell autoantigens involved in neonatal thymectomy-induced murine autoimmune gastritis. Studies using monoclonal autoantibodies.

Autoimmune gastritis accompanied by autoantibodies to parietal cells was induced in BALB/c nu/+ mice by neonatal thymectomy 2-4 days after birth. Three monoclonal autoantibodies, designated as 2B6 (IgG1), 2G10 (IgG2b), and 1H9 (IgG1), were obtained from one of these mice. All three reacted specifically with parietal cells, 2G10 recognizing species-specific antigenic determinants and 2B6 and 1H9 recognizing interspecies-specific antigenic determinants. All three recognized antigens on the membrane of intracellular secretory canaliculi and the cytoplasmic tubulovesicular system of parietal cells. At least two different molecular groups were recognized by these antibodies; 2B6 recognizing a 65,000-79,000-mol wt group and 1H9 recognizing a 92,000-120,000-mol wt group. Sera of most mice with autoimmune gastritis reacted with either or both groups. Both groups were consistently coprecipitated by any of the three antibodies when solubilized in NP-40. Sera, from patients with pernicious anemia, containing anti-parietal cell antibodies could also precipitate these two groups of antigens. Competition assay and physicochemical studies showed that the epitopes recognized by the three monoclonal antibodies are different.

Anemia, Pernicious↗
PubMed1989

Sialyl SSEA-1 antigen as a carbohydrate marker of human natural killer cells and immature lymphoid cells.

The distribution of a carbohydrate antigen, the sialyl SSEA-1 (sialyl Lex-i), in human lymphoid cells was investigated by flow cytometry with a specific monoclonal antibody, MoAb FH-6. We concluded that the lymphocytes positive for the sialyl SSEA-1 antigen present in normal peripheral blood (PB) are natural killer (NK) cells since the positive cells had an NK activity toward K562 cells, and most of the sialyl SSEA-1+ cells were simultaneously positive for Leu-11 (CD-16) and Leu-19. Essentially, no T and B cells, defined by Leu-4 (CD3) and Leu-16 (CD20), were positive for the sialyl SSEA-1 antigen in PB samples taken from healthy donors and patients with disorders unrelated to lymphoid malignancies. Among the malignant lymphoid cells, many sialylated SSEA-1+ cells were observed in large granular lymphocyte (LGL) leukemia cells and some acute lymphoblastic leukemia (ALL) blasts, but not in CLL cells or malignant lymphoma cells. Sialyl SSEA-1 was also positive in some cultured human lymphoid cell lines. We conclude that expression of the sialyl SSEA-1 antigen is strictly limited to a distinct population of NK cells among the mature lymphocytes in normal PB, but the antigen is present in a wide range of immature lymphoblasts of T- and B-cell lineages as well as the NK-cell lineage. The sialyl SSEA-1 antigen disappears from the surface of immature lymphocytes of T- and B-cell lineages during the course of maturation.

Antibodies, Monoclonal↗
PubMed1989

[Clinical application of cancer-associated carbohydrate antigens in the diagnosis and therapy of human cancers].

Cell surface carbohydrates are important cancer-associated antigens. The carbohydrate antigens which have been proved to be useful for the serum diagnosis of human cancers are classified from their biochemical primary structure into three categories; the type 1 chain antigens, type 2 chain antigens, and core structure-associated antigens. The SPan-1 antigen, the newly-introduced tumor marker for human pancreas cancers, seems to be a type 1 chain antigen, judging from its distribution pattern among human cancers and its good correlation with other type 1 chain antigens. Another newly-introduced tumor marker, the CA54/61 antigen, which is specific for ovarian cancers, seems to belong to the family of the core-structure-associated antigens, since both antibodies (MA54 and MA61) used for the detection of the CA54/61 antigen are shown to recognize the antigen molecule which is closely related to sialyl Tn antigen, the well-known carbohydrate core structure of mucins. There are two approaches for the therapy of human cancers employing carbohydrate antigens as target molecules. One is the direct application of the specific monoclonal antibodies (alone, or in the drug-conjugated forms) in cancer patients. In this case, special attention is paid to the use of murine antibodies in human patients. The other approach is to induce specifically an effective immune response against the cancer-associated carbohydrate antigens. For this approach, further methodological development is necessary to determine how to obtain an effective immune response to carbohydrate antigens, since they have long been known as very poor immunogens which are T-independent.

Antigens, Tumor-Associated, Carbohydrate↗
PubMed1988

Monoclonal antibodies directed to a disulfated glycosphingolipid, SB1a (GgOse4Cer-II3IV3-bis-sulfate), associated with human hepatocellular carcinoma.

Two murine monoclonal antibodies, 2H6G5 (IgM) and 4A9E10 (IgG3), were obtained by using either cultured human hepatocellular carcinoma cells (PLC/PRF/5) or the acidic glycolipid mixture prepared from the same cells as immunogens. The antigen in PLC/PRF/5 cell membranes recognized by both antibodies was identified as a disulfated acidic glycolipid, GgOse4Cer-II3IV3-bis-sulfate (SB1a). Both antibodies reacted specifically with SB1a, and no significant reactivity was noted with other sulfated glycolipids or gangliosides except that the antibody 2H6G5 showed a weak cross-reactivity with LacCer-II3-sulfate (SM3), another sulfated glycolipid which partly shares the same carbohydrate structure as SB1a. The SB1a antigen is a relatively minor glycolipid in PLC/PRF/5 cells, but it was strongly expressed at the surface of PLC/PRF/5 cells as ascertained by cytofluorometry using both antibodies. A significant amount of SB1a antigen was present in 3 of the acidic glycolipid fractions isolated from 15 human hepatocellular carcinoma tissues as well as in the acidic glycolipid fraction prepared from PLC/PRF/5 cells, while all the acidic glycolipid fractions prepared from cirrhotic livers and a normal liver were essentially negative for SB1a, as ascertained by both solid phase enzyme immunoassay and the thin-layer chromatography-immunostaining method. These results strongly suggest that the SB1a antigen as defined by these new monoclonal antibodies is associated with human hepatocellular carcinoma.

Animals↗
PubMed1988

Quantitative and qualitative characterization of human cancer-associated serum glycoprotein antigens expressing epitopes consisting of sialyl or sialyl-fucosyl type 1 chain.

The levels of carbohydrate antigens having epitopes consisting of type 1 chain (R----Gal beta 1----GlcNAc beta 1----3Gal beta 1----R) in the sera of patients with various malignant and nonmalignant disorders have been investigated with the use of three monoclonal antibodies, N-19-9, FH-7, and FH-9. Serum levels of 2----3 sialylated Lea antigen and 2----6 sialylated Lea antigen, defined respectively by antibodies N-19-9 and FH-7, were found to be frequently high in patients with cancer of the digestive system, particularly pancreatic cancer. High levels of 2----3,2----6 disialylated Lc4 antigen, defined by antibody FH-9, were less frequent in cancer patients when compared with the other two antigens. In patients with nonmalignant disorders, especially renal and autoimmune diseases, serum levels of the two type 1 chain antigens defined by FH-7 and FH-9 were more frequently high than that defined by N-19-9. Molecular weights and other general biochemical characteristics of serum mucin carrying the type 1 chain determinants were not significantly different in cancer patients as compared with patients with nonmalignant disorders. However, the degree of glycosylation of the antigen, as assessed by its solubility in perchloric acid, showed significant differences; i.e., the mucin antigen carrying 2----6 sialylated Lea determinant in the sera of patients with nonmalignant disorders had the highest carbohydrate/protein ratio, followed by the mucin carrying the same determinant in the sera of cancer patients. Mucin antigen carrying 2----3 sialylated Lea antigen or 2----3, 2----6 disialylated Lc4 antigen in cancer patients had the lowest carbohydrate/protein ratio among the four groups tested. Thus, the carbohydrate/protein ratio in the type 1 chain mucin antigens in sera of normal subjects is higher than that in sera of cancer patients (P less than 0.05). This finding is in contrast to previous findings on the mucin antigens carrying the type 2 chain determinant (R. Kannagi et al., Cancer Res., 46: 2619-2626, 1986), in which the mucin antigen in cancer patients was found to have a much higher carbohydrate/protein ratio than that carrying the same antigenic determinants in patients with nonmalignant disorders.

Antibodies, Monoclonal↗
PubMed1988

Fucosylated type-2 chain polylactosamine antigens in human lung cancer.

Four specific monoclonal antibodies (MAbs) have been used to study distributions of fucosylated type-2 chain polylactosamine antigens, Lex, poly Lex, Ley and sialylated Lex-i antigens, in human lung cancer tissues and in the serum of patients with lung cancers. Radioimmunoassay frequently showed abnormally high antigen levels in the sera of 66 lung cancer patients tested. When histological typing was performed, high serum levels of the above 4 antigens were most frequently observed in patients with adenocarcinoma of the lung; i.e., after combining the results from the 4 antigens, 75% of the sera from patients with lung adenocarcinoma were positive (50% in the case of large-cell carcinoma, 30% in the case of squamous-cell carcinoma and 27% for small-cell carcinoma). Among the 4 antigens, the sialylated Lex-i antigen had the highest positive incidence, 58%, in the sera of patients with adenocarcinoma of the lung, compared to 33% for Ley, 29% for poly Lex, and 8% for Lex antigen. On the other hand, when the distributions of these antigens in the lung cancer tissues of 42 patients were studied by immunohistological techniques, the Ley antigen had the highest positive incidence, 100%, in lung adenocarcinoma tissues, poly Lex antigen had 86%, sialylated Lex-i antigen had 71%, and Lex antigen had 29%. In cancer tissues, the incidence of non-sialylated antigens, such as Ley, poly Lex and Lex antigens, often exceeds the positive incidence of the sialylated antigen, but the sialylated form of the antigen, such as sialylated Lex-i antigen, appears more often than the non-sialylated form in patients' sera.

Adenocarcinoma↗
PubMed1988

Significance of 2-3 and 2-6 sialylation of Lewis a antigen in pancreas cancer.

Distributions of sialylated derivatives of Lewis a (Lea) antigen in cancer tissue of the human pancreas and in the sera of patients with pancreas diseases have been studied; the significance of 2-3 and 2-6 sialylation of Lea antigens in pancreas cancer have been investigated using specific monoclonal antibodies. In most pancreas cancer tissue the 2-3 sialylated Lea antigen was found to be specifically distributed in cancer cells as determined by immunohistologic techniques, while a significantly smaller amount of the antigen was detected in surrounding nonmalignant pancreas tissue, which was infiltrated by cancer cells. Conversely, the 2-6 sialylated Lea antigen was abundantly present in nonmalignant pancreas tissue, while it was less frequently present in pancreas cancer cells. When the sera of 66 patients with pancreas diseases were examined for these sialylated Lea antigens, correlation studies showed that the levels of 2-3 sialylated Lea tended to be 44.1 times more than the levels of 2-6 sialylated Lea in the sera of cancer patients. The average ratio of 2-3 sialylated Lea to 2-6 sialylated Lea was 0.23 in the sera of patients with pancreatitis. These data collectively indicate that the 2-3 sialylation of Lea is remarkably enhanced, and the 2-6 sialylation of Lea antigen is suppressed in pancreas cancer. The determination of the 2-3 sialylated Lea to 2-6 sialylated Lea ratio in patients with pancreas diseases may be helpful for the differential diagnosis of pancreas cancer and nonmalignant pancreatic disorders.

Antibodies, Monoclonal↗
PubMed1988

Glycolipid-directed FH6 monoclonal antibody recognizes high molecular weight glycoprotein antigen carrying sialyl Lex-i determinant in the culture supernatant of PC-9 cells.

The properties of the antigen recognized by monoclonal antibody FH6 have been analyzed. FH6 was originally generated against a glycolipid, i.e. a difucoganglioside isolated from human colonic adenocarcinoma, and specifically reacts with sialyl Lex-i determinant. Several culture supernatants of human carcinoma cell line cells were found to have high levels of FH6-reactive antigen, and PC-9, a human lung carcinoma cell line was used for the analysis. A solid-phase sandwich radioimmunoassay was performed to detect the antigen. The antigenic activity was extractable in 0.6 M PCA or 7% TCA, and was sensitive to mild alkaline treatment and to Pronase digestion. Most of the antigen was eluted in the void volume of a Sepharose CL-2B column, which indicates that its molecular weight is greater than several million. It was eluted from a DEAE-cellulose column at a NaCl concentration in the range of 0.2-0.25 M. The immunoaffinity-purified antigen has a high carbohydrate content of more than 80%. These data indicate that the antigen recognized by FH6 in the culture supernatant of PC-9 is not a glycolipid, but a high molecular weight glycoprotein which could be referred to as a mucin, or a proteoglycan, which contains keratan-sulfate like glycosaminoglycan chains, as judged from the results of the glycosidase treatments.

Antibodies, Monoclonal↗
PubMed1987

Monoclonal antibodies directed to chemically synthesized lactogangliotetraosylceramide, a leukemia-associated antigen having a novel branching structure.

Murine leukemia cells (M1), in their undifferentiated state, have been characterized by the presence of cancer-associated lactoganglio-series glycolipids, one of which was identified as lactogangliotetraosylceramide (LcGg4) having a novel branching at the II-Gal of lactosylceramide through GlcNAc beta 1----3 and GalNAc beta 1----4 linkage, as shown below (Kannagi, R., Levery, S.B., and Hakomori, S. (1984) J. Biol. Chem., 259, 8444-8451): GalNAc beta 1----4 Gal beta 1----4Glc beta 1----1Cer GlcNac beta 1----3 Since this glycolipid is a very minor component, it has been difficult to obtain enough of the purified glycolipid for the preparation of a monoclonal antibody. We developed a method to chemically synthesize this glycolipid using a lactose unit, a ceramide unit, and two hexosamine donors as synthons and made the synthetic glycolipid available as an immunogen. The two monoclonal antibodies we obtained (YI328-18 and YI328-51, both IgG3) specifically recognized the novel branching structure and had no cross-reactivity with gangliotriaosylceramide or lactotriaosylceramide. Thus, the antibodies were found to be useful probes to detect lactogangliotetraosylceramide expressed in undifferentiated M1 leukemia cells, which disappears on induced differentiation. The results of this study indicate a new strategy to establish monoclonal antibody directed to novel minor glycolipid markers or their artificially designed analogs, employing chemically synthesized glycolipid antigens.

Animals↗