Autoantibodies to T and B cell lines detected in serum samples from patients with systemic lupus erythematosus with lymphopenia and hypocomplementaemia

Antibodies to lymphocytes in serum samples from 88 patients with systemic lupus erythematosus (SLE) and 15 normal control subjects were examined by a cell enzyme linked immunosorbent assay (ELISA) with four human T and B cell lines as antigens. The antibodies reacted with the Wa B cell line and the T cell lines P12 (CD4-, CD8+), Jurkat (CD4-, CD8-), and Hut78 (CD4+, CD8-). Antibody titres in serum samples from patients with SLE were higher than in those from normal control subjects. Titres of antibodies to P12 were correlated with titres of antibodies to Wa, Jurkat, and Hut78 in serum samples from patients with SLE. IgG antibodies to P12 were associated with lymphopenia and reduced haemolytic complement. By thin layer chromatography immunostaining, the antibodies in serum samples from two of 10 patients with SLE with high titres of IgG antibodies to P12 and lymphopenia were shown to react with three monosialoglycosphingolipids and two neutral glycosphingolipids from P12 cells. Antibodies to lymphocytes in serum samples from patients with SLE react with T and B cell lines, recognise a series of cell membrane glycosphingolipids and are associated with the lymphopenia and hypocomplementaemia typical of active disease.

Menstrual cycle-associated expression of 2-hydroxy fatty acyl phytosphingosine-containing GlcCer, LacCer and Gb3Cer in human uterine endometrium

In the previous study, we found that sulfatide was characteristically expressed in the secretory phase of human uterine endometrium and that the metabolism of glycosphingolipids was strictly controlled by sex steroid hormones. Therefore, the neutral glycosphingolipid composition of human uterine endometrium in the proliferative and secretory phases was analyzed and was found to be characteristic in both phases. The major neutral glycolipids were GlcCer, LacCer, Gb3Cer and Gb4Cer. The concentrations of GlcCer, LacCer and Gb3Cer in the secretory phase were higher than those in the proliferative phase. Furthermore, on TLC, GlcCer, LacCer and Gb3Cer in the proliferative phase gave three bands, the 3rd band, which migrated to the lowest position, being much more predominant in the secretory phase. The individual band materials in both phases were purified by silica gel column chromatography, and their structures were analyzed by FABMS and GLC. The lower-migrating bands of GlcCer, LacCer and Gb3Cer were found to contain molecules with 2-hydroxy fatty acyl phytosphingosine, indicating that hydroxylation of the fatty acid and sphingosine moieties to give 2-hydroxy fatty acid- and phytosphingosine-containing glycosphingolipids, respectively, is induced selectively in the secretory phase on a change in the hormonal environment.

Human uterine endometrial adenocarcinoma: characteristic acquirement of synthetic potentials for II3SO3-LacCer and ganglio series sulfoglycosphingolipids after transfer of the cancer cells to culture

The acidic glycosphingolipid composition of human uterine endometrial adenocarcinoma was compared with those of normal uterine endometrium at the proliferative and the secretory phases. Upon chemical composition analysis, no significant transformation-associated change of these glycolipids was observed. However, when cancer cells from the patients with human uterine endometrial adenocarcinoma were transferred to culture, the composition of glycosphingolipids, particularly sulfoglycosphingolipids, was significantly altered after the 70th doubling time. I3SO3-GalCer, which was contained in the original tissues of uterine endometrial adenocarcinomas, disappeared completely from the cultured cells at the 70th doubling time, whereas II3SO3-LacCer and ganglio series sulfoglycosphingolipids, which were originally contained in a trace amount or not present at all in the cancer tissues, became the major components in the total acidic glycosphingolipids in the cultured cells. Also, among cell lines established from several gynecological cancers, which include uterine cervical squamous carcinoma, uterine endometrial adenocarcinoma, ovarian clear cell carcinoma, choriocarcinoma, uterine sarcoma, ovarian sarcoma, and vulvar melanoma, only those cells derived from uterine endometrial adenocarcinoma expressed II3SO3-LacCer and ganglio series sulfoglycosphingolipids and the synthetic activities of these sulfoglycolipids, indicating that uterine endometrial adenocarcinoma cells characteristically lose the sulfotransferase to GalCer and acquire the sulfotransferase to LacCer after being transferred to culture in vitro. Thus, the unique sulfoglycosphingolipids and sulfotransferase are useful markers for the characterization of uterine endometrial adenocarcinoma among human gynecological cancers.

Glycosphingolipids of various human ovarian tumors: a significantly high expression of I3SO3GalCer and Lewis antigen in mucinous cystadenocarcinoma

Among several human ovarian tumors, which include mucinous cystadenocarcinoma, serous cystadenocarcinoma, and clear cell adenocarcinoma, the mucinous cystadenocarcinoma showed a unique glycosphingolipid composition. In particular, more than 90% of the acidic glycosphingolipids in the mucinous cystadenocarcinoma is comprised of sulfolipids, which are hardly detected in normal ovary and are contained in concentrations of less than 40% in the other type of ovarian tumors. By means of negative ion fast atom bombardment mass spectrometry and gas liquid chromatography, the major sulfolipid in mucinous cystadenocarcinoma is confirmed to be I3SO3-GalCer with N-cerebronoyl phytosphingosine, that which contrasts with I3SO3-GalCer with N-nonhydroxy fatty acyl sphingosine as the major molecular species in the other ovarian cancers. In mucinous cystadenocarcinoma, galactosylceramide is found in the relatively high concentration and is also composed of N-cerebronoyl phytosphingosine. In addition, the concentrations of glycolipids with Le(a) and Le(b) antigenicities are significantly higher in mucinous cystadenocarcinoma than those in normal ovary and the other ovarian tumors.

Hemolysis of human erythrocytes is a new bioactivity of gangliosides

Using sheep erythrocytes and liposomes, an inhibitory effect of gangliosides has been shown on the activation of the alternative pathway of complement. However, in studies using human erythrocytes, we found that gangliosides had hemolytic activity that was possibly mediated through activation of the alternative pathway. Pretreatment of human erythrocytes obtained from healthy volunteers or paroxysmal nocturnal hemoglobinuria (PNH) patients with a ganglioside mixture purified from human erythrocytes enhanced their susceptibility to homologous human complement, and resulted in dose-dependent hemolysis. The enhancement was more marked in PNH erythrocytes than control cells. Protease treatment of the ganglioside mixture did not change its hemolytic activity, but sialidase treatment abolished the activity. Among the major erythrocyte gangliosides, II3NeuAc-LacCer (GM3) was the most potent hemolytic agent. Gangliosides purified from bovine brain were also active, while neither nonsialylated glycosphingolipids, the ceramide moiety, or sialic acid alone were active. Sialic acid residues in the ganglioside molecules were essential to this activity, but the amount of the residue or the source of the gangliosides seemed not to be important. Several treatments inhibiting the alternative but not classical complement pathway markedly reduced the ganglioside hemolytic activity. This novel bioactivity of gangliosides was thus suggested to be mediated partly by activation of the alternative pathway.

Concanavalin A-stimulated expression of gangliosides with GalNAc beta 1-4(NeuAc alpha 2-3)Gal beta structure in murine thymocytes

We analysed the glycolipids of mouse thymocytes before and after Concanavalin A (Con A) or recombinant interleukin-2 (rIL-2) stimulation by TLC-immunostaining with carbohydrate-specific antiglycolipid antibodies. The thymocytes were cultured in serum-free medium in the presence of 500 ng ml-1 Con A, 10 U ml-1 rIL-2 or Con A plus rIL-2 for 6, 12, 24, 48, and 72 h, and were found to start proliferating 24 h after cultivation in the presence of Con A or Con A plus rIL-2, the maximum levels being reached at 72 h and 48 h, respectively, in a thymidine uptake experiment. The concentrations of II3Neu-Gg4Cer, Gg4Cer and IV3GalNAc alpha-Gb4Cer after 48 h Con A stimulation were found to be at almost the original levels. Conversely, II3Neu-Gg3Cer, which was not detected in the thymocytes at the start, began to appear after 48 h stimulation with Con A and Con A plus rIL-2, and IV3Neu-Gg5Cer in the cells 48 h after stimulation with Con A and Con A plus rIL-2 has increased to 41 and 44 times higher than in the original cells, respectively, as judged on TLC-immunostaining with monoclonal antibody YHD-06, which detects the GalNAc beta 1-4(NeuAc or NeuGc alpha 2-3)Gal beta-structure. These results indicate that the increased synthesis of both gangliosides, in other words, the activation of N-acetylgalactosaminyltransferase, is associated with the mitogen-induced proliferation.(ABSTRACT TRUNCATED AT 250 WORDS)

Characteristic expression of cholesterol sulfate in rabbit endometrium during the implantation period

Sialic acids and sulfate residues are the major negative-charged cellular components, which are considered to be crucial in embryonal adhesion to the endometrium. To explore the mechanism of implantation, we examined the change in the amounts of these substances in the rabbit endometrium during the implantation period. Gangliosides and sulfatides were present in very small quantity in the endometrium irrespective of the reproductive stage. Though the content of cholesterol sulfate was relatively low in the nonpregnant endometrium, it abruptly increased at day 5 of pregnancy, i.e. at the beginning of implantation, followed by a gradual decline toward day 9. Cholesterol sulfate level in the inter-implantation sites was about twice as much as that in the implantation sites and was comparable with that in the pseudopregnant endometrium. These results demonstrate that cholesterol sulfate is a major negative-charged lipid in the peri-implantation endometrium in rabbits. We further point to the difference in the concentration of cholesterol sulfate between implantation and interimplantation sites, thus suggesting cholesterol sulfate as a major participant in the process of implantation.

Preferential reactivity of autoantibodies in murine lupus NZB mice to neuraminidase-treated monosialogangliosides on B cells of mouse spleen

When analyzed by flow cytometry, reactivity of IgM autoantibodies in sera from NZB mice to spleen B cells, but not to T cells, from BALB/c mice was remarkably increased after treatment of the cells with Vibrio cholerae neuraminidase. By TLC immunostaining with the antibodies, neither neutral nor acidic glycosphingolipids from both BALB/c and NZB mouse spleens were found to be reactive, but after neuraminidase treatment of the TLC plate, prior to the immunostaining, three components became reactive. All of the reactive glycosphingolipids were found to carry a single sialic acid residue and were at a concentration less than 1.3% of the total lipid-bound sialic acids. Their mobilities on TLC plate were close to those of IV3 NeuAcnLc4Cer, IV3 NeuAcII3 NeuAcGg4Cer, and IV3 NeuAcII3 NeuAc2Gg4Cer. In addition, the monosialogangliosides, which became reactive with the autoantibodies after neuraminidase treatment, were found to be predominantly distributed on B cells from BALB/c mice spleen, but not on T cells by TLC immunostaining. These studies demonstrate that the majority of IgM autoantibodies to spleen lymphocytes in sera from NZB mice might react preferentially to terminal sugar residues of three new glycosphingolipids masked by a single sialic acid on B cells, but not on T cells.

Fucosylated glycoconjugates in human dorsal root ganglion cells with unmyelinated axons

The same subset of small neurons in human dorsal root ganglia (DRG) was recognized by both of the two probes binding to fucosylated residue. Ulex europaeus agglutinin I (UEA-1) lectin and anti-fucosyl GM1 antibody, although these probes bind to different glycoconjugates. UEA-1 lectin also bound to unmyelinated axons in DRG and in biopsied sural nerve, but not to any neurons or unmyelinated axons in the sympathetic ganglia. Thus UEA-1 lectin and anti-fucosyl GM1 antibody may be used as specific probes for primary sensory neurons with unmyelinated axons.

Identification of glycolipid receptors for Helicobacter pylori by TLC-immunostaining

Helicobacter pylori has been identified as a causative agent in active chronic gastritis. The receptor for this bacteria, however, is not known. It is likely that the receptor molecules may be glycosphingolipids as shown in the cases of other bacteria. We explored this possibility by a thin-layer chromatography (TLC)-immunostaining method. Among glycosphingolipids extracted from human gastric mucosa, intact Helicobacter pylori specifically bound to I3SO3-GalCer and II3NeuAc-LacCer, whereas no specific binding to neutral glycosphingolipids, which share the same ceramide moiety with I3SO3-GalCer or II3NeuAc-LacCer, was demonstrated. Sonicated bacteria could still bind to II3NeuAc-LacCer with comparable affinity. In contrast, the binding of bacteria to I3SO3-GalCer was greatly diminished upon sonication. These results suggest that each of the oligosaccharide moieties of II3NeuAc-LacCer and I3SO3-GalCer may be specifically recognized by different ligand molecules of Helicobacter pylori.

Enhancement of keratin synthesis induced by lipokeratinogenoside, N-(O-linoleoyl)-omega-hydroxy fatty acyl sphingosyl glucose, in association with alteration of the intracellular Ca(2+)-content and protein kinase in cultured keratinocytes (FRSK)

Lipokeratinogenoside [N-(O-linoleoyl)-omega-hydroxy fatty acyl sphingosyl beta-glucose] is one of the epidermosides which were found to be glycosphingolipids characteristic of the epidermis of mammalian skin. On the addition of lipokeratinogenoside to cultured rat keratinocytes (FRSK), the amount of keratin in the cells increased, 48 and 144 h after cultivation, to 1.4 to 1.8 times higher than that without the addition of lipokeratinogenoside, and the number of cornified envelopes also significantly increased on cultivation of the cells with lipokeratinogenoside. Immunohistochemical staining with anti-keratin antibody revealed that the cells cultivated with lipokeratinogenoside were densely covered with keratin in distinct contrast to the control cells. The same enhanced syntheses of keratin and cornified envelopes were observed on cultivation in the presence of TPA, which has been shown to elevate the intracellular Ca(2+)-content and to translocate cytoplasmic protein kinase C to the plasma membrane in the initial stage of transmembrane signalling. Similarly, lipokeratinogenoside showed the ability to increase the intracellular Ca(2+)-content to the same extent as TPA did and to translocate protein kinase C to the membrane fraction. However, the above activities of lipokeratinogenoside decreased with removal of the linoleic acid moiety from lipokeratinogenoside with mild alkali, but linoleic acid alone did not show any activities, indicating that the lipokeratinogenoside molecule itself is required for expression of the activities.

Ganglioside GD3 shedding by human gliomas

The proportion of ganglioside GD3 increases in glioma tissue and GD3 content is correlated with malignancy of gliomas. This ganglioside can be detected in the sera of patients with glioma by thin-layer chromatographic analysis. Ganglioside GD3 was not detected in the sera of healthy donors and astrocytoma grade 2 patients. However, serum GD3 was detected in one of three astrocytoma grade 3 patients and seven of nine glioblastoma patients. These results show that shedding of GD3 increases in proportion to the degree of malignancy of gliomas. Nevertheless, all of the glioblastoma patients in this study were advanced cases. Considering the high reliability of radiological diagnostic techniques in the neurosurgical field, further study will be necessary to clarify the relationships between the GD3 level in serum and the properties of tumours.

The B subunit of cholera toxin enhances DNA synthesis in rat hepatocytes induced by insulin and epidermal growth factor

The B subunit of cholera toxin, which binds to ganglioside GM1, enhanced DNA synthesis in rat hepatocytes in primary culture induced by insulin and/or epidermal growth factor. The effect was dose-dependent, and whole cholera toxin, activating adenylate cyclase, showed a higher effect than the B subunit alone. The B subunit acted additively with other agents that also increase cyclic AMP levels. A competitive antagonist of cyclic AMP could not suppress the effect of the B subunit completely. These data suggest that the effect is independent of the cyclic AMP signal pathway, and that GM1 plays a role in hepatocyte proliferation.

Characteristic binding of human plasma apolipoprotein B to gangliotetraosylceramide and gangliotriaosylceramide

The binding of human plasma low-density lipoproteins (LDL), freshly prepared by discontinuous ultracentrifugation, to several neutral and acidic glycosphingolipids was examined by TLC immunostaining with the anti [apolipoprotein B (apoB)] antibody. ApoB was found to bind characteristically to the asialogangliosides, gangliotetraosylceramide (Gg4Cer) and gangliotriaosylceramide (Gg3Cer), the former being a more potent receptor than the latter, indicating that the sequences Gal beta 1-3GalNAc beta 1-4Gal and GalNAc beta 1-4Gal are involved in the binding of apoB. A weak positive reaction with fucosylgangliotetraosylceramide (IV2Fuc-Gg4Cer), which has the same internal recognition sequences, was also observed (the binding ability was only 1/7 of that in the case of Gg4Cer). No binding to other neutral glycosphingolipids, or glycosphingolipid sulfates (I3-SO3-GalCer) and gangliosides, was detected, and therefore substitution of the receptor glycolipid with sialic acid was thought to inhibit the binding. The results indicate that, along with the binding of apoB to the LDL-binding domain of the receptor glycoprotein, interaction with some carbohydrate chains in the receptor, or with glycolipids coexisting on the plasma membrane, may be important for the binding of apoB to cells.

Characteristic differences in the lipid composition of middle ear effusions in adult and pediatric patients: phosphatidylethanolamine and phosphatidylserine levels

Middle ear effusions (MEEs) from adult patients with otitis media with effusion are usually serous in nature, but those from pediatric patients younger than 8 years old are frequently mucous in consistency. MEEs contain substances secreted by the epithelial cells of the middle ear and eustachian tube to regulate surface tensions as well as those produced as the result of inflammation. Since the biochemical bases of serous and mucous MEEs have not been clearly established, we analyzed all lipid components of MEEs from seven children and seven adults by thin-layer and gas-liquid chromatography, and also compared them with those from sera. Although no significant difference in the lipid composition was observed between adult and pediatric sera, the relative concentration of phosphatidylethanolamine (PE) in the pediatric MEEs was 26.5%, while that in the adult MEEs was 9.2% and was significantly different. A similar high concentration of phosphatidylserine (PS) was also observed in the pediatric MEE. Since phospholipids are major components of surfactants secreted from the epithelial cells of the middle ear, significantly high concentrations of both PE and PS as charged phospholipids may be responsible in part for the mucoid characteristics seen in pediatric MEEs.

Hepatocyte plasma membrane glycosphingolipid reactive with sera from patients with autoimmune chronic active hepatitis: its identification as sulfatide

Sera from patients with autoimmune chronic active hepatitis were found to contain IgG-class antibody to the acidic glycosphingolipid fraction from rabbit hepatocyte plasma membrane by solid-phase enzyme-linked immunosorbent assay. Using serum positive for the antibody as a probe, we isolated the target antigen by Iatrobeads column chromatography. Analysis by thin-layer chromatography and negative ion fast atom-bombardment mass spectrometry revealed that the antigen was sulfatide. The presence of antisulfatide antibody was also confirmed by immunoblotting. The reactivity of the serum with sulfatide was diminished by preincubation of the serum with galactosylceramide-6-sulfate and sulfatide, indicating that the antibody reacted with sulfated galactosylceramide regardless of the position of the sulfate residue. The antibody was found in 92.3%, 42.9%, 15.8%, 14.2%, 0% and 0%, respectively, of patients with autoimmune chronic active hepatitis, primary biliary cirrhosis, cirrhosis, systemic lupus erythematosus, chronic active hepatitis and chronic persistent hepatitis. Thus antisulfatide antibody was characteristic of autoimmune-type chronic liver diseases. Antisulfatide antibody was absorbed by rabbit hepatocyte plasma membrane. Preincubation of sera with sulfatide immobilized on Sepharose decreased their reactivities with not only sulfatide but also rabbit plasma membrane and rat hepatocytes. Therefore sulfatide may be a target antigen of the antibody to hepatocyte surface membrane.

Activation of keratinization of keratinocytes from fetal rat skin with N-(O-linoleoyl) omega-hydroxy fatty acyl sphingosyl glucose (lipokeratinogenoside) as a marker of epidermis

To elucidate the functional significance of sphingolipids altered in the epidermal differentiation, we examined, the effects of sphingolipids on the activity of transglutaminase and the formation of cornified envelopes in the keratinocytes from fetal rat skin. N-(O-linoleoyl) omega-hydroxy fatty acyl sphingosyl glucose (lipokeratinogenoside) that was characteristically contained in the mammalian epidermis, as well as nonhydroxy fatty acid-containing GalCer and GlcCer, significantly enhanced the activity and the formation, but no or rather inhibited activity was observed with ceramides, GalCer with alpha-hydroxy fatty acid, saponified lipokeratinogenoside, etc. This indicates that skin-characteristic lipokeratinogenoside functions to regulate the transglutaminase for the formation of cornified envelopes in the process of keratinization.

Comprehensive computer system in the outpatient clinic

A clinical computing system in a one-physician outpatient clinic is described. It consists of a computer-stored medical history at its center with associated blood examination equipment, a drug delivering machine and a cost calculation program. Two-month's experience has demonstrated its eligibility to clinical practice.

Altered expression of gangliosides in erythrocytes of paroxysmal nocturnal hemoglobinuria

In paroxysmal nocturnal hemoglobinuria (PNH), impaired glycosyl-phosphatidylinositol (PI)-anchoring of membrane proteins such as decay-accelerating factor has been known to lead to increased susceptibility to complement. Moreover, abnormal expression of non-PI-anchoring glycoproteins such as C3b/C4b receptor (CR1) or glycophorin-alpha also has been shown in PNH. Therefore, we biochemically analyzed glycosphingolipids (GSL) as one of the membrane glycoconjugates of PNH erythrocytes. Erythrocytes of all seven PNH patients showed altered expression of sialosyl GSL (gangliosides) as compared with the control erythrocytes of healthy donors. Both a sialosylparagloboside (IV6NeuAc-nLc4Cer) among four major gangliosides and some minor gangliosides in normal erythrocytes variably disappeared in erythrocytes from the peripheral blood of PNH patients. As one of the possible mechanisms of altered expression of gangliosides in PNH erythrocytes, structural analysis suggested impaired sialylation of GSL. These results suggest not only the altered metabolism of gangliosides in PNH erythrocytes, but also a metabolic disorder of membrane glycoconjugates as a new feature of PNH.

Monoclonal antibody to galactosylceramide: discrimination of structural difference in the ceramide moiety

A mouse monoclonal antibody (mAb) was developed against monohexaosylceramide. This mAb differentially reacted on thin-layer chromatograms with 3 types of galactosylceramide (GalCer) obtained from bovine brain. Structural analysis of the 3 glycolipids revealed that they consisted of the same galactose and sphingosine but of apparently different fatty acids. Among the GalCers, the mAb reacted with teh two GalCers which contained alpha-hydroxy fatty acids, but not with GalCer composed of nonhydroxy fatty acids. These findings suggest that not only that the mAb discriminated the fatty acid composition in the ceramide moiety of GalCer, but also that the ceramide structure defines the immunological epitope as it is known to do for the carbohydrate moiety of glycosphingolipid.

Human monoclonal antibody (HMST-1) against lacto-series type 1 chain and expression of the chain in uterine endometrial cancers

A human monoclonal antibody termed HMST-1 was produced by fusing lymphocytes from segments of human pelvic lymph nodes from an endometrial cancer patient with murine myeloma cells. The epitope recognized by HMST-1 was determined to be lacto-series type 1 chain-containing glycosphingolipid (Gal beta 1-3GlcNAc beta 1-3Gal beta 1-4Glc beta 1-1Cer) by isolating the antigen from endometrial cancer cell line SNG-II and analyzing with fast atom bombardment mass spectrometry, permethylation analysis, and exoglycosidase treatment. By the immunohistochemical avidin-biotin-peroxidase complex method, no normal endometrium and benign endometrial hyperplasia were stained with HMST-1, but HMST-1 reacted with about 35% of endometrial cancer cases. These facts indicate that the rate of expression of the antigen increases along with the course of malignancy in the endometrium. By sialidase treatment of the section, the positive rate increased to 57% in endometrial cancers and to 13% in normal endometrium, indicating that the antigen was masked with sialic acid and exposed by neuraminidase treatment. Immunohistochemistry also revealed that the antibody reacted with human fetal alimentary tract epithelium and mesothelium, indicating the oncodevelopmental nature of Gal beta 1-3GlcNAc beta 1-3Gal beta 1-4Glc beta 1-1Cer.

A monoclonal antibody (MSN-1) against a newly established uterine endometrial cancer cell line (SNG-II) and its application to immunohistochemistry and flow cytometry

To determine a phenotypic difference between normal endometrium and endometrial adenocarcinoma, a new monoclonal antibody (MSN-1) was produced by immunizing a new endometrial cancer cell line (SNG-II), which was established in 1981 from a 43-year-old Japanese woman with stage II uterine endometrial cancer. MSN-1 recognized the Lewis-b carbohydrate moiety on the cell surface glycolipid and seldom reacted immunohistochemically with normal endometrium but with about 90% of endometrial cancer cases. By application of MSN-1 to flow cytometry, the possibility of differentiating endometrial normal cells from cancer cells was demonstrated.

Significant increase in the antibody to Gal alpha 1-3Gal structure in sera of patients with hepatocellular carcinoma after transcatheter arterial embolization

Sera from the patients with chronic liver diseases and hepatocellular carcinoma (HCC) were tested for reactivity with neutral glycosphingolipids extracted from rabbit liver plasma membrane by enzyme-linked immunosorbent assay and thin-layer chromatography immunostaining. IgG class antibody to neutral glycosphingolipids was detected in 29.6% (8 of 27), 6.3% (1 of 16), 0% (0 of 8), 0% (0 of 25), and 6.9% (2 of 29) in the sera of patients with HCC, liver cirrhosis, autoimmune chronic active hepatitis, chronic hepatitis, and normal individuals, respectively. Using the serum positive for the antibody to neutral glycosphingolipids, the target antigen glycolipid was isolated. Negative ion fast atom bombardment mass spectrometry, exoglycosidases treatment, and permethylation analysis revealed that the main target antigen was IV3 alpha Gal-nLc4Cer. In enzyme-linked immunosorbent assay, IgG class antibody to IV3 alpha Gal-nLc4Cer was detected in 33.3% (9 of 27), 18.8% (3 of 16), 25% (2 of 8), 4% (1 of 25), and 6% (3 of 50) in the sera of patients with HCC, liver cirrhosis, autoimmune chronic active hepatitis, chronic hepatitis, and normal individuals, respectively. Of 9 HCC patients positive for the antibody, 6 had received transcatheter arterial embolization (TAE) therapy. Six of 10 patients who received TAE therapy had the antibody, whereas only 3 of 17 patients without TAE therapy had the antibody. This antibody may be a heterophile antibody, which recognizes Gal alpha 1-3Gal structure at the nonreducing terminal of the antigen. Since the occurrence of this antibody was closely related with TAE therapy, the necrosis of HCC induced by TAE therapy may stimulate the production of the antibody.

Discrimination of human dorsal root ganglion cells by anti-fucosyl GM1 antibody

Some neurons and surrounding satellite cells in human dorsal root ganglia were immunostained with rabbit IgM antibody against the ganglioside fucosyl GM1. They were not immunostained with the anti-GM1 antiserum. Immunohistochemical discrimination of neurons in human dorsal root ganglia by the anti-fucosyl GM1 antibody may give us an important clue to the functional identification of neurons conveying different modalities of sensation.

Alpha 2- and beta-adrenergic receptors and adenosine A1 receptor of FRTL-5 rat thyroid cells in relation to fucosyl GM1 ganglioside

We have previously reported that anti-fucosyl GM1 ganglioside antibody partially suppresses cAMP production in FRTL-5 rat thyroid cells not via the TSH receptor but via guanine nucleotide-binding protein indirectly. In order to clarify further the mechanism of the antibody action, we studied the relationship with alpha 2- and beta-adrenergic and adenosine A1 receptors. FRTL-5 cells did not bind [3H]clonidine, suggesting the lack of alpha 2-adrenergic receptor or at least abnormality of its binding domain. On the other hand, the cells specifically bound [125I]iodocyanopindolol, but isoproterenol failed to affect the basal and TSH-stimulated cAMP production indicating the lack of coupling with adenylate cyclase. The inhibition of cAMP production induced by anti-fucosyl GM1 antibody was not altered by adrenergic agents. [125I]hydroxyphenylisopropyl adenosine binding was observed in FRTL-5 cells but was not displaced by the antibody. These results lead to conclusions that FRTL-5 cells lack alpha 2-adrenergic receptor but have beta-adrenergic receptor which lacks coupling with adenylate cyclase and have adenosine A1 receptor, and that the adrenergic receptors and adenosine A1 receptor are not the site of action of anti-fucosyl GM1 antibody.