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R Kannagi

Publications and source records attributed to R Kannagi.

At least 91 records · Page 5Linked to original sources
PubMed1994

A revised structure for the disialosyl globo-series gangliosides of human erythrocytes and chicken skeletal muscle.

Disialosyl globo-series gangliosides have previously been isolated from chicken skeletal muscle (E. L. Hogan, R. D. Happel, and J.-L. Chien (1982) Adv. Exp. Med. Biol. 152, 273-278; S. Dasgupta, J.-L. Chien, E. L. Hogan, and H. van Halbeek (1991) J. Lipid Res. 32, 499-506) and human erythrocytes (S. K. Kundu, B. E. Samuelsson, I. Pascher, and D. Marcus (1983) J. Biol. Chem. 258, 13857-13866). In both cases, the structure of this ganglioside was proposed to be NeuAc alpha 2-->3(NeuAc alpha 2-->6)Gal beta 1-->3GalNAc beta 1-->3Gal alpha 1-->Gal alpha 1-->4Gal beta 1-->1Cer (V3NeuAcV6NeuAcGb5Cer). We have reinvestigated the human erythrocyte antigen and now propose an alternative structure differing in the location of the NeuAc alpha 2-->6 residue: NeuAc alpha 2-->3Gal beta 1-->3 (NeuAc alpha 2-->6)GalNAc beta 1-->3Gal alpha 1-->4Gal beta 1-->4Glc beta 1-->1 Cer (V3NeuAcIV6NeuAcGb5Cer). This novel structure is supported by results of 1H-NMR spectroscopy, negative ion fast atom bombardment mass spectrometry, and methylation linkage analysis with capillary gas chromatography--mass spectrometry in both electron impact and chemical ionization modes. Furthermore, based on new results from negative ion fast atom bombardment mass spectrometry and linkage analysis, we propose that the chicken skeletal muscle antigen also has this revised structure, differing only in ceramide composition. The terminal tetrasaccharide of these gangliosides is identical to that of GD1 alpha, NeuAc alpha 2-->3Gal beta 1-->3(NeuAc alpha 2-->6)GalNAc beta 1-->4Gal beta 1-->4Glc beta 1-->1 Cer(IV3NeuAcIII6NeuAcGg4Cer), previously identified in a rat ascites hepatoma cell line (T. Taki, Y. Hirabayashi, H. Ishikawa, S. Ando, K. Kon, Y. Tanaka, and M. Matsumoto (1986) J. Biol. Chem. 261, 3075-3078) and a murine lymphoma cell line with low metastatic potential (K. Murayama, S. B. Levery, V. Schirrmacher, and S. Hakomori (1986) Cancer Res. 46, 1395-1402), although they appear to be immunologically distinct.

Animals↗
PubMed1994

Expression of neural cell adhesion molecule in normal gastric mucosa and in gastric carcinoid tumors.

Expression of neural cell adhesion molecule (NCAM) in the digestive system was studied with NE-150 monoclonal antibody, together with those against Lewis blood group antigens. NE-150 did not react with any of 32 cell lines tested derived from digestive tract cancers. In gastric adenocarcinomas NCAM was not expressed regardless of its differentiation status, while in gastric carcinoids and in other carcinoid tumors of different organs, it was present in all the specimens tested. Among normal tissues, it reacted with the deep gastric gland and the islets of Langerhans. These results suggest that NCAM is one of the most specific markers for gastric carcinoid tumors. It was also suggested that the gastric carcinoid tumor might be derived from NCAM-positive cells in the deep gastric gland. These findings should be exploitable in subgrouping gastric tumors in terms of antigen expression.

Adenocarcinoma↗
PubMed1993

Expression of alpha-(1,3)-fucosyltransferases which synthesize sialyl Le(x) and sialyl Le(a), the carbohydrate ligands for E- and P-selectins,in human malignant cell lines.

Transcripts of alpha-(1,3)-fucosyltransferases in human epithelial cancer and leukemia cell lines were analyzed by Northern blotting and reverse transcriptase mediated-polymerase chain reaction using specific probes and primers which can discriminate between the transcripts derived from the four alpha-(1,3)-fucosyltransferase genes Fuc-TIII, IV, V, and VI. Flow cytometric analysis of the sialyl Le(x) and sialyl Le(a) antigens was also performed on the same cell lines. The sialyl Le(x) antigen was expressed on 14 of 15 epithelial cancer cell lines, and the sialyl Le(a) antigen was detected on 8 of them. The message of Fuc-TIII was detected in most of the epithelial cancer cell lines (14 of 15), which correlated with the surface expression of these carbohydrate determinants. In addition, the messages of Fuc-TIV and Fuc-TVI were detected in most epithelial cancer cell lines, while the message of Fuc-TV was undetectable in most of them. On the other hand, all leukemia cell lines were positively stained for sialyl Le(x), but none of them was stained for sialyl Le(a) in flow cytometry. The messages of Fuc-TIV++ were detected in all leukemia cell lines tested. Small quantities of Fuc-TIII, V, and/or VI messages were also detected in some leukemia cell lines in reverse transcriptase mediated-polymerase chain reaction analysis. These studies indicate that alpha-(1,3)-fucosyltransferase activities in epithelial cancer and leukemia cell lines are mixtures of multiple molecular species of alpha-(1,3)-fucosyltransferases. It is natural that epithelial cancer cells contain a significant amount of Fuc-TIII mRNA and leukemia cell lines contain Fuc-TIV mRNA, since their normal counterparts, normal epithelial cells and leukocytes, respectively, are known to contain these fucosyltransferases. The unexpectedly frequent occurrence of Fuc-TIV mRNA in epithelial cancer cell lines may be related to their retro-differentiation associated with tumorigenesis. Another unexpected finding was a weak but significant expression of the alpha-(1,3)-fucosyltransferases Fuc-TIII, V, and/or VI in leukemia cell lines detected by reverse transcriptase mediated-polymerase chain reaction analysis. Since these enzymes are known to be capable of synthesizing the sialyl Le(x) determinant, this finding implies a possibility that some of them may be involved in the synthesis of sialyl Le(x) in leukemia cells.

Adenocarcinoma↗
PubMed1993

A distinct type of sialyl Lewis X antigen defined by a novel monoclonal antibody is selectively expressed on helper memory T cells.

A subset of human helper memory T cells is known to adhere to E-selectin expressed on cytokine-activated endothelial cells. However, sialyl Lex antigen, the carbohydrate ligand for E-selectin, has been hardly detectable on these cells, at least when typical anti-sialyl Lex antibodies were used for detection. One of the MoAbs (2F3, IgM), which we raised against a chemically synthesized sialyl Lex glycolipid preparation, is found to react selectively to CD4+ CD45RObright+ CD45RA- helper memory T cells among peripheral lymphocytes in healthy individuals. The specificity of the antibody is in clear contrast to that of the hitherto reported typical anti-sialyl Lex antibodies FH-6 and SNH-3. These classical anti-sialyl Lex antibodies were known to react to a subset of natural killer (NK) cells, but were not reactive with any particular subset of resting peripheral T or B cells of healthy individuals if the cells were not activated. On the other hand, the newly generated 2F3 antibody specifically reacted to helper memory T cells, and did not react to NK cells, B cells, or any T cells other than helper memory T cells. When tested against the sialyl Lex-active glycolipid antigen, the reactivity of 2F3 was not significantly different from that of the classical anti-sialyl Lex antibodies. But when tested against oligosaccharides prepared from cellular glycoproteins, 2F3 detected a distinct set of O-linked oligosaccharides, which were not reactive to the classical anti-sialyl Lex antibodies. Our results suggest that various molecular species of sialyl Lex antigens are present on carbohydrate side chains of cellular glycoproteins, and that helper memory T cells express a distinct type of sialyl Lex antigen that is defined by 2F3 but is not efficiently detected by other typical anti-sialyl Lex antibodies. Among cultured lymphocytic leukemia cells, the adult T-cell leukemia (ATL) cells preferentially expressed the 2F3-defined antigen, and acute lymphocytic leukemia cells rarely expressed the antigen. The cultured ATL cells expressing the 2F3-defined antigen showed a clear E-selectin-dependent adhesion to cytokin-activated endothelial cells, and the 2F3-defined sialyl Lex antigen served as a ligand for E-selectin as ascertained by the clear inhibition of adhesion with the 2F3 antibody.(ABSTRACT TRUNCATED AT 400 WORDS)

Antibodies, Monoclonal↗
PubMed1993

Specific expression of a complex sialyl Lewis X antigen on high endothelial venules of human lymph nodes: possible candidate for L-selectin ligand.

L-selectin is a cell adhesion molecule that mediates homing of lymphocytes to the peripheral lymph nodes and is speculated to bind to the carbohydrate determinant which is specifically expressed by the endothelial cells of high endothelial venules (HEVs) in the peripheral lymph nodes. One of the murine monoclonal antibodies (2H5, IgM, kappa), which was raised against sialyl LeX-active glycolipids which have long and complicated carbohydrate structures, was found to react strongly to the HEV endothelial cells of the human peripheral lymph nodes, while the typical anti-sialyl LeX antibodies SNH-3, FH-6 and CSLEX-1 failed to detect the antigen on HEV under the same condition. This new antibody was reactive to essentially all endothelial cells of HEV in the peripheral lymph nodes, and moderately to some endothelial cells in Payer's patches and appendices, but never reacted with the endothelial cells of post capillary venules in the spleen, thymus, or other organs. The 2H5 antibody detected three major glycoproteins of 90, 110 and 250 kDa, the most abundant molecular species being 110 kDa, in the stroma of human lymph nodes. In Stamper-Woodruff assays employing cryostat sections of human lymph nodes, the 2H5 antibody significantly inhibited the adhesion of peripheral lymphocytes to the endothelial cells of HEV. These results indicate that the carbohydrate antigens defined by the 2H5 antibody, most probably sialyl LeX determinants having complex carbohydrate structures, serve as the ligand for L-selectin on HEV endothelial cells.

Antibodies, Monoclonal↗
PubMed1993

Contribution of carbohydrate antigens sialyl Lewis A and sialyl Lewis X to adhesion of human cancer cells to vascular endothelium.

The carbohydrate antigen, sialyl Lex, is known to be a ligand for the cell adhesion molecule called ELAM-1 (E-selectin, endothelial cell leukocyte adhesion molecule-1), which is present on cytokine-activated human endothelial cells. Recently, we reported that another carbohydrate antigen, sialyl Lea, can also serve as a ligand for ELAM-1 (A. Takada, K. Ohmori, N. Takahashi, K. Tsuyuoka, K. Yago, K. Zenita, A. Hasegawa, and R. Kannagi, Biochem. Biophys. Res. Commun., 179: 713-719, 1991). Both sialyl Lex and sialyl Lea are expressed in many human malignant cells. In order to assess the contribution of these carbohydrate antigens to the adhesion of human malignant cells to vascular endothelium, we selected a panel of 12 cultured human epithelial cancer cell lines and a panel of 12 human leukemia cell lines which express sialyl Lex and/or sialyl Lea antigens. All 12 epithelial cancer cell lines exhibited a clearly ELAM-1-dependent adhesion to cytokine-activated human umbilical vein endothelial cells, while only 3 of the 12 leukemia cell lines exhibited significant participation of ELAM-1 in the adhesion. With regard to epithelial cancer cells, the adhesion of 6 cancer cell lines, mostly of colon and pancreas origin, was dependent almost exclusively on sialyl Lea. A significant contribution of the sialyl Lex antigen was noted in the adhesion of the other 6 cell lines, including cancers of lung and liver origin. These results imply that the sialyl Lea/ELAM-1 adhesion system, as well as the sialyl Lex/ELAM-1 adhesion system, plays an important role in the adhesion of human cancer cells to human umbilical vein endothelial cells. With regard to leukemia cells, on the other hand, adhesion of the 3 leukemia cell lines that showed ELAM-1-dependent adhesion was mediated by the sialyl Lex antigen, and none of these leukemia cell lines expressed sialyl Lea or exhibited sialyl Lea-dependent adhesion.

Antigens, Tumor-Associated, Carbohydrate↗
PubMed1993

Differentiation-dependent expression of sialyl stage-specific embryonic antigen-1 and I-antigens on human lymphoid cells and its implications for carbohydrate-mediated adhesion to vascular endothelium.

Expression of two developmentally regulated carbohydrate antigens, the sialyl stage-specific embryonic antigen-1 (SSEA-1) and I-antigens, in human lymphocytes and lymphocytic leukemia cells was investigated using specific monoclonal antibodies. Sialyl SSEA-1 was expressed only on natural killer (NK) cells, and was essentially absent on resting mature T and B cells among normal peripheral lymphocytes. On the other hand, the I-antigen was strongly expressed on virtually all mature B cells, moderately expressed on most mature T cells, but not expressed on NK cells in normal donors. Expression of the two antigens on normal T and B cells was reversible; in vitro stimulation of normal lymphocytes with concanavalin A (Con A) resulted in the loss of I-antigen and appearance of sialyl SSEA-1 on CD3+ T blasts, whereas stimulation with pokeweed mitogen led to loss of I-antigen expression and appearance of sialyl SSEA-1 antigen on CD19+ B blasts. Among lymphocytic leukemia cells, sialyl SSEA-1 was detected primarily on leukemia cells having immature properties such as most common acute lymphocytic leukemia (cALL) blasts, while the I-antigen was frequently expressed on malignant cells having relatively mature properties, such as those found in adult T-cell leukemia or chronic lymphocytic leukemia, and only occasionally on cALL blasts. Among normal peripheral lymphocytes, the sialyl SSEA-1+I-antigen- NK cells selectively underwent E-selectin (ELAM-1, endothelial-leukocyte adhesion molecule-1)-dependent adhesion to endothelial cells, while the I-antigen+sialyl SSEA-1- mature T and B cells did not, in line with the recent finding that sialyl SSEA-1 serves as a specific ligand for E-selectin. Con A blasts, which are sialyl SSEA-1+I-antigen-, also exhibited significant E-selectin-dependent adhesion to endothelial cells. These results indicate that expression of the sialyl SSEA-1 and I-antigens varies alternately depending on the differentiation/activation status of the lymphocytes, and that this at least partly regulates the behavior of lymphocytes at the vessel wall.

Antibodies, Monoclonal↗
PubMed1993

Immunohistochemical localization of lipocortins in normal and psoriatic human skin.

The distribution of lipocortin I, a steroid-induced inhibitory protein of phospholipase A2, was examined in normal and psoriatic human skin. Using immunoblotting analysis with specific antibody against human lipocortin I purified from human placenta, lipocortin I was detected as a 37 kDa protein in cultured epidermal cells, whole skin and epidermis. In the dermis and stratum corneum, lipocortin I was only weakly detectable by Western blotting. In contrast to normal skin, much less lipocortin I was detected by Western blotting analysis in psoriatic skin. Using immunoperoxidase immunohistochemical analysis, lipocortin I was demonstrated in the cytoplasm of keratinocytes in the upper and middle layers of the epidermis and in some infiltrating cells in the dermis in normal skin. In involved psoriatic skin, by contrast, lipocortin I was almost undetectable in the epidermis, although it was demonstrated in some infiltrating cells in the dermis. No immunostaining of lipocortin I was observed in the stratum corneum of normal or psoriatic skin. These results, together with the finding that phospholipase A2 activity is higher in psoriatic epidermis than in normal epidermis, suggest that lipocortin I plays an important role in the regulation of differentiation and proliferation of epidermal keratinocytes.

Annexin A1↗
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

[Cell adhesion mediated by ELAM-1 (endothelial leukocyte cell adhesion molecule-1, E-selectin) and carbohydrate determinants].

ELAM-1 (endothelial-leukocyte adhesion molecule-1, E-selectin) is a cell adhesion molecule which is specifically expressed on cytokine-activated endothelial cells. It is known to bind a carbohydrate antigen sialyl Le(x) (sialyl SSEA-1) present on leukocytes, and the sialyl Le(x)/ELAM-1 adhesion system is suggested to play a physiologically important role in leukocyte recruitment in the process of inflammation. Some leukemia cells also express the sialyl Le(x) antigen, and in such a case, the sialyl Le(x)/ELAM-1 adhesion system will be involved in the organ infiltration of leukemia cells. On the other hand, in the adhesion of human cancer cells to endothelial cells, another carbohydrate antigen, sialyl Le(a), serves as the ligand for ELAM-1, as well as sialyl Le(x). These two carbohydrate determinants, sialyl Le(a) and sialyl Le(a), on cancer cells will be involved in the hematogenous metastasis of cancer cells. The physiological function of these two carbohydrate determinants at the surface of normal epithelial cells is most probably to mediate stage-specific cell-to-cell recognition and adhesion during the course of organogenesis in developing embryos, and the abnormal cell-adhesion behaviors of cancer cells are the results of aberrant expression of cell adhesion molecules which would play physiologically important roles under normal condition.

Cell Adhesion↗
PubMed1993

[Flow cytometry in clinical laboratory medicine].

Flow cytometric analysis of blood cells is an important technique for the evaluation of the immunological functions of patients with various disorders, and also for the differential diagnosis of leukemias. In the lymphocyte subset analysis, special attention should be paid to the optimal gating of lymphocytes. We recommend the use of CD13 and CD33 to ascertain more accurate gating of lymphocytes and more efficient monitoring of the contamination of non-lymphoid cells, especially in patients with PNH, in addition to CD45 and CD14, which are already utilized routinely. We also feel that 2-color and 3-color analyses should be applied more frequently for the routine laboratory tests for lymphocyte subsets. With regard to the analysis of leukemia cells, the combined use of nuclear DNA content or TdT (terminal deoxynucleotidyl transferase) with other routine cellular markers is quite useful for the analysis of a small number of leukemia cells, and enables the differentiation of leukemia cells from the contaminating non-malignant cells, particularly in the analysis of the minimal residual diseases. Among the cellular markers defined by specific monoclonal antibodies, we stress the physiological significance of recently developed cell adhesion molecules, such as selectins and their carbohydrate ligands, which are closely involved in the recruitment of leukocytes in inflammatory responses, as well as in the infiltration processes of leukemia cells.

Antibodies, Monoclonal↗
PubMed1992

Stage-specific expression of cancer-associated type 1 and type 2 chain polylactosamine antigens in the developing pancreas of human embryos.

Expression of type 1 and type 2 chain carbohydrate antigens during the course of morphogenesis of human embryonic pancreas was investigated using specific monoclonal antibodies and compared with the carbohydrate antigen profiles of human pancreatic cancers. The type 2 chain antigens, such as stage-specific embryonic antigen 1 (Le(x)) and I-antigens, appeared much earlier than the type 1 chain antigens; the epithelial cells of primitive foregut were Le(x)+I-antigen- in the embryos at Carnegie stages 16-23, while the pancreatic primordial cells, which had differentiated from the Le(x)+ gut epithelial cells, were Le(x)-I-antigen+ at Carnegie stages 22-23. The type 1 chain antigens, such as Le(a), Le(b), Le(c), and their sialylated derivatives, were not expressed in any cells at these stages and appeared much later in the pancreas of the 10-12-week embryos, when the primitive pancreatic ductal cells in the primordia exhibited an extensive budding of the daughter cells. At this stage, Le(a) appeared and was expressed strongly in the epithelial cells of primitive pancreatic ducts as well as in the daughter cells that were destined to differentiate into future centroacinar cells; Le(b) was localized in the daughter cells which were to become future acinar cells; and Le(c) was specifically expressed in the daughter cells which were to form future Langerhans islets. With regard to the sialylated derivatives of Le(a), expression of the 2-3 sialyl Le(a) antigen was limited to the epithelial cells of the primitive pancreatic ducts, while the 2-6 sialyl Le(a) antigen was strongly expressed in the future centroacinar cells, which had differentiated from the corresponding daughter cells. Among these antigens, the Le(a) and 2-3 sialyl Le(a) antigens showed the highest incidence in human pancreatic cancer tissues. These results indicate that the expression of these carbohydrate antigens in embryonic pancreas is differentiation dependent and cell lineage specific and that most human pancreatic cancer cells mimic the carbohydrate antigen profile of the epithelial cells of the primitive pancreatic ducts in human embryos.

Adult↗
PubMed1992

First establishment of a human monoclonal antibody directed to sulfated glycosphingolipids SM4s-Gal and SM4g, from a patient with lung cancer.

Several human monoclonal antibodies directed to tumor-associated glycolipid antigens have been established, but more than one-half of them react with gangliosides and the others react with neutral glycolipids. We report here the first establishment of a human IgM monoclonal antibody directed to the sulfated glycolipid. This monoclonal antibody, M14-376, did not react with SM3 and SB1a which have a terminal HSO3----3Gal beta 1----R1, but with the simple sulfolipids SM4s-Gal and SM4g which contain a terminal HSO3----3Gal beta 1----O----CH2----R2; however, lyso-SM4s-Gal and lyso-SM4g did not bind M14-376. These results suggest that terminal HSO3----3Gal and part of the hydrophobic region of the glycolipid are recognized by M14-376. Directly biotinylated M14-376 was used for immunohistochemical staining of 140 formalin-fixed, paraffin-embedded lung cancer tissue sections to study the distribution of the antigen. A high incidence of positive staining was found in adenocarcinoma (39.5%, 17 of 43), followed by large cell carcinoma (20.0%, 5 of 25), while this antigen was rarely detected in small cell carcinoma (4.7%, 1 of 21) and squamous cell carcinoma (3.9%, 2 of 51). Thin layer chromatography immunostaining of glycolipids extracted from lung cancer tissues showed the presence of only SM4s-Gal in adenocarcinoma, but SM4g was not found in any subtype of lung cancer. Immunohistochemical staining revealed that this antigen was expressed in normal kidney, testis, and brain, but erythrocytes, granulocytes, and lymphocytes were negative in cytofluorometric analysis.

Adenocarcinoma↗
PubMed1992

Identification of immuno-reactive lipocortin 1-like molecules in serum and plasma by an enzyme immunoassay for lipocortin 1.

A two-site enzyme immunoassay for lipocortin 1 (LC1) has been developed. The detection limit of LC1 was 0.2 ng/tube and the optimal assay range was 1 to 100 ng/tube. The assay system enabled us to identify immunoreactive lipocortin 1-like molecules (IR-LC1) in human serum and plasma. Normal human serum and plasma IR-LC1 concentrations were 44.6 ng/ml for males and 43.1 ng/ml for females with no significant difference between both sexes. The age-related analysis among nine age groups from newborn to 69 years old revealed that the serum or plasma level was high in infants (77.5 ng/ml for newborn and 75.6 ng/ml for 1 month-1 year group), and the 40-year-old (52.2 ng/ml) and 50-year-old (51.3 ng/ml) groups. The major population of plasma IR-LC1 was of 70 kDa in size corresponding to that of the LC1 homodimer. The present enzyme immunoassay system is sufficiently sensitive for the clinical study of LC1 in human body fluids, tissues and organs.

Adolescent↗
PubMed1992

[Study of anti-idiotype antibodies to human monoclonal antibody].

A human monoclonal antibody, ll-50 (IgM, lambda), was generated, which reacted specifically with a major of glycolipid present in LS174T colon cancer cells. The glycolipid antigen which reacted with the ll-50 antibody was expected to four sugar residues from its TLC mobility, and it was ascertained that the glycolipid antigen which reacted with ll-50 antibody might be Lc4 antigen [Gal beta 1----3 GLcNAc beta 1----3 Gal beta 1----4 Glc beta 1----1 Cer] judging from TLC immunostaining and ELISA when the reactivity of ll-50 antibody was tested using various pure glycolipids in 3-5 sugar residues as an antigen. Sera in patients with malignant disorders and healthy individuals were analyzed by Sandwich assay of immobilized and biotinylated ll-50 antibody. The serum of the Lc4 antigen recognized by ll-50 antibody was significantly higher in patients with malignant disorders than that in healthy individuals (p less than 0.05). Three mouse monoclonal anti-idiotype antibodies, G3, B3 and C5 (all IgG1), were generated by the immunization of BALB/c mice with ll-50 antibody. These anti-idiotype antibodies specifically bound to to human monoclonal antibody, ll-50 and had a significant inhibitory activity towards the binding of ll-50 antibody to the Lc4 antigen. This indicated that these anti-idiotype antibodies, G3, B3, and C5, were paratope-related anti-idiotype antibodies. G3, B3, and C5 were expected to define the nearest idiotope because they could mutually inhibit ll-50 antibody. Sera in patients with malignant disorders and healthy individuals were analyzed by Sandwich assay of immobilized and biotinylated anti-idiotype antibodies, G3, B3, and C5. As to the ll-50 like antibodies defined by C5 (Id-C5+), the mean serum level in patients with malignant disorders was significantly higher than that in healthy individuals (p less than 0.05). As to the ll-50 like antibodies defined by B3 (Id-B3+), the mean serum level in patients with malignant disorders was significantly higher than that in healthy individuals.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1991

Adhesion of human cancer cells to vascular endothelium mediated by a carbohydrate antigen, sialyl Lewis A.

Recently the lectin-like domain on ELAM-1 (endothelial leukocyte adhesion molecule-1) was shown to recognize a carbohydrate antigen, sialyl Lewis x. In this paper we demonstrate, by a series of inhibition experiments utilizing specific monoclonal antibodies and pure glycolipid preparations, that the sialyl Lewis a antigen serves as a specific ligand for ELAM-1 as well as sialyl Lewis x and plays a significant role in the ELAM-1-mediated binding of human cancer cells to activated endothelial cells.

Antibodies, Monoclonal↗
PubMed1991

Tissue distribution of 2-3 and 2-6 sialyl Lewis A antigens and significance of the ratio of two antigens for the differential diagnosis of malignant and benign disorders of the digestive tract.

The authors investigated the tissue distribution of two kinds of sialylated derivatives of Lewis A (Le(a)) antigen in patients with cancers of the digestive system using specific monoclonal antibodies, and evaluated the significance of determining the 2-3 and 2-6 sialylated Le(a) antigen levels for the diagnosis of cancer. In most specimens from patients with cancers of the pancreas, biliary tract, stomach, and colon, the 2-3 sialylated Le(a) antigen was strongly expressed in cancer cells. However, 2-6 sialylated Le(a) antigen was less frequently expressed in cancer cells. The former is therefore more specific to cancer than the latter. Also, the serum level of the 2-3 sialylated Le(a) antigen was significantly higher than that of the 2-6 counterpart in patients with cancers of pancreas, biliary tract, stomach, and colon. The resulting ratio of serum 2-3/2-6 sialylated Le(a) antigens was frequently high in patients with malignancy and was low in patients with benign disorders of these digestive organs. Therefore, the 2-3/2-6 sialylated Le(a) antigen ratio is a useful for the differential diagnosis of malignant disorders in these organs. However, liver disorders were found to be exceptional in that both antigens were mostly absent in hepatocellular carcinoma (HCC) cells in immunohistologic examination, as well as in nonmalignant parenchymal liver cells. Only the epithelial cells of the intrahepatic bile ducts expressed the 2-6 sialylated Le(a) antigen strongly, and expressed the 2-3 sialylated Le(a) antigen moderately. The levels of both antigens were sometimes high in patients with liver disorders, but the ratio always remained low in patients with HCC as well as benign liver disorders such as cirrhosis or chronic hepatitis. The sialylated Le(a) antigens, which sometimes accumulate in the sera of patients with HCC, were concluded to originate from the epithelial cells of the proliferating small bile ducts, and those serum antigens cannot be considered as evidence for the presence of liver cancer cells.

Antibodies, Monoclonal↗