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Biomedical subjects

O Tarutani

Publications and source records attributed to O Tarutani.

At least 37 records · Page 2Linked to original sources
PubMed1988

Antigenic determinants on thyroglobulin: comparison of the reactivities of different thyroglobulin preparations with serum antibodies and T cells of patients with chronic thyroiditis.

To delineate the antigenic determinants on thyroglobulin (Tg) recognized by serum autoantibodies and peripheral blood T cells from patients with chronic thyroiditis, we studied the reactivities of three different Tg preparations, i.e. enzyme-digested Tg fragments, physically or chemically denatured Tg, or Tg with differing iodine contents. Human Tg was digested with staphylococcal V8 protease, and the fragments were separated by high performance liquid chromatography. The autoantibodies reacted with the larger fragments, but their ability to bind to small fragments was limited. On the other hand, T cells reacted similarly with all fragments, regardless of mol wt. The autoantibodies bound little to denatured Tg after its disulfide bonds were destroyed with dithiothreitol or 2-mercaptoethanol, while the reactivity of heat-denatured Tg was partially decreased, and that of Tg denatured with sodium dodecyl sulfate was conserved. Conversely, T cells reacted with Tg denatured by heating or dithiothreitol treatment. These results indicate that autoantibodies recognize mainly a conformational structure of Tg, presumably containing disulfide bonds, whereas T cells recognize the primary structure of Tg. Variations in the iodine content of Tg were not associated with altered reactivity with autoantibodies or T cells. We propose that variations in Tg conformation related to iodination of the molecule do not contribute significantly to its reactivity with autoantibodies and T cells. In addition, T cells reacted with the smaller Tg fragments containing few T3 or T4 residues to a greater extent than they did with larger Tg fragments with the same amount of T3 or T4 as native Tg. Therefore, it appears that the Tg-reactive T cells predominantly recognize determinants on the Tg molecule that are unrelated to hormone-containing sites.

Adolescent↗
PubMed1988

Thyroglobulin and thyroid peroxidase share common epitopes recognized by autoantibodies in patients with chronic autoimmune thyroiditis.

Monoclonal antibodies specific for human thyroid peroxidase (TPO) were prepared by the hybridoma technique using hyperimmune spleen cells from mice immunized with TPO purified from thyroid glands from patients with Graves' disease. Use of the microenzyme-linked immunosorbent assay method revealed that some of the monoclonal antibodies cross-reacted strongly with human thyroglobulin (Tg). Conversely, monoclonal anti-Tg antibodies cross-reacted with TPO, albeit to a lesser degree. Some anti-Tg autoantibodies in serum from patients with chronic autoimmune thyroiditis purified by Tg affinity chromatography bound TPO, and such binding was completely inhibited by Tg. Western blotting experiments revealed that thyroid microsomal 103K proteins recognized by mouse monoclonal and polyclonal anti-TPO antibodies were recognized by some monoclonal anti-Tg antibodies and anti-Tg autoantibodies, and conversely, that 19S Tg was recognized by some monoclonal anti-TPO antibodies. TPO was immunoprecipitated by anti-Tg autoantibodies isolated by Tg affinity chromatography. On the other hand, the specificity for TPO of the anti-Tg autoantibodies was not identical with that of anti-TPO autoantibodies. These cross-reactivities were not due to contamination of TPO with Tg or vice versa, or to contamination of the anti-Tg autoantibody preparations with anti-TPO autoantibodies. Taken together, these data indicate that Tg and TPO share common antigenic determinants and that some of those determinants are recognized by autoantibodies in the serum of patients with chronic autoimmune thyroiditis.

Adolescent↗
PubMed1988

Peroxidase activity and thyroglobulin iodination activity of thyroid peroxidase in non-functioning thyroid tumours.

Both lesion (L) and adjacent normal (N) thyroid tissue from 48 patients with non-functioning adenomas and adenomatous goitres were assayed for peroxidase activity by the 'mini' assay method employing guaiacol or iodide as the second substrate. A considerable proportion of thyroids (46% of adenomas and 22% of adenomatous goitres) demonstrated no iodide oxidation activity in L although they had guaiacol oxidation activity, and these were grouped as subgroups A. The rest of these non-functioning tumours, termed subgroups B, had both guaiacol and iodide oxidation activity which was higher (3.0-4.6 times in guaiacol assay and 7.3-14.1 times in iodide assay) in L than in N. These data indicate that the non-functioning in subgroups A may be due to a lack of iodide oxidation activity and that some other defects such as an iodide transport defect may be involved in subgroups B. Furthermore, a precise and rapid assay method for thyroglobulin iodination activity of thyroid peroxidase was developed, with modifications of previous methods. On the basis of this method, we found that there is a good correlation (r = 0.94) between iodide oxidation assay and thyroglobulin iodination assay, leading to the conclusion that thyroglobulin iodination assay can be replaced by iodide oxidation assay.

Adenoma↗
PubMed1987

Enzyme-linked immunosorbent assay (ELISA) for IgG antibodies to thyroglobulin.

We used a computer programmed standard IgG curve for computer-assisted quantification of assay results for autoantibodies to thyroglobulin (Tg) by quantitative enzyme-linked immunosorbent assay (ELISA). Specific antibody levels in unknowns were quantified by comparison of their optical density readings with a standard curve of absorbance vs concentration obtained with dilutions of the reference serum. Anti-Tg antibodies were detected in 80% of the patients with chronic thyroiditis and 90% of those with Graves' disease. Anti-Tg antibodies were also detected in 14.3% of the healthy controls. The titer of anti-Tg antibodies detected by tanned red cell hemagglutination correlated well with that detected by ELISA, although, the sensitivity of the ELISA was higher. By our computer-assisted conversion method, the anti-Tg antibody can be readily and reliably quantified and low titer antibodies to Tg can be detected with adequate precision.

Adolescent↗
PubMed1986

[Peroxidase activity of thyroid tissue in toxic diffuse goiter. Difference among thyroids administered antithyroid drugs and potassium iodide].

Peroxidase activity in thyroid tissue from 25 patients with Graves' disease was measured by Mini assay method (J. Biochem. 98, 637-647, 1985) employing guaiacol or iodide as a second substrate. The mean values of protein-based specific activity were 0.496 guaiacol unit/mg protein and 0.187 iodide unit/mg protein, reaching 16 fold and 28 fold those of normal thyroids, respectively. The mean value of ratio of iodide unit to guaiacol unit in each thyroid, 0.68, was also much higher than that of normal human thyroid, 0.16. No significant difference in peroxidase activity was observed between patients treated with methylmercaptoimidazole and those with propylthiouracil, but the activities of those groups were significantly higher than those of patients treated with potassium iodide, suggesting that inorganic iodine therapy plays some role in suppressing the synthesis of thyroid peroxidase in vivo.

Adolescent↗
PubMed1986

[Serum thyroglobulin levels in patients with thyroid tumor].

Serum thyroglobulin (Tg) levels were measured in 15 normal volunteers, 69 patients with differentiated thyroid carcinoma, 22 with adenoma, 45 with adenomatous goiter, 5 with functioning adenoma and 24 with Graves' disease, utilizing a double antibody radioimmunoassay technique. Serum Tg levels in the normal volunteers were found to be less than 30 ng/ml as determined from their mean value, i.e., 16.9 +/- 13.4 ng/ml (mean + 2SD), whereas serum Tg in the patients with various thyroid disorders showed significantly elevated (P less than 0.01). Serum Tg of patients with differentiated thyroid carcinoma without distant metastasis was 71 +/- 7 ng/ml (mean +/- SE), that in adenoma 124 +/- 22 ng/ml, that in adenomatous goiter 147 +/- 19 ng/ml, that in functioning adenoma 120 +/- 41 ng/ml, and that in Basedow disease 122 +/- 22 ng/ml. Furthermore, it appears that Tg concentration in serum is correlated with the size of the nodules in differentiated thyroid carcinoma (P less than 0.01) and benign nodules (P less than 0.05). Present results suggest that thyroid tumor also release Tg into serum in addition to Tg stored in the normal tissue. Furthermore, the level of circulating Tg in patient is not correlated to the level of serum TSH. In treated differentiated thyroid carcinoma, serum Tg levels were markedly reduced (21 +/- 2 ng/ml) in patients with no evidence of either recurrences or metastases, but significantly elevated in those with recurrences and/or metastases (257 +/- 109 ng/ml). Therefore, serum Tg measurements in the follow-up of patients treated for differentiated thyroid carcinoma are useful in the search for recurrences or metastases.

Adenoma↗
PubMed1986

Antigenic determinants on thyroglobulin recognized by T cells in patients with chronic thyroiditis.

It was found that the proliferating cells to thyroglobulin (Tg) in patients with chronic thyroiditis are confined to a T cell subpopulation. Then, we attempted to characterize the antigenic determinants of Tg recognized by T cells from patients with chronic thyroiditis by Tg-induced DNA-synthetic response. T cells from patients could respond to Tgs from whales, pigs and chickens as well as to human Tg. These findings indicated that epitopes on Tg recognized by T cells were shared by Tgs from various species. In addition, the T cells from different individuals varied in specificity.

Adolescent↗
PubMed1986

Genetic control of the production of anti-thyroid hormone antibodies in mice immunized with human thyroglobulin.

Various strains of mice with different H-2 and Igh-I allotypes were immunized with human thyroglobulin (HTg) and genetic control of the production of anti-thyroid hormone antibodies was examined. Anti-HTg antisera obtained from different strains of mice were examined for the presence of anti-thyroid hormone antibodies. At least one Ir-gene which controls the production of anti-T4 antibodies by immunization with HTg was identified in the I-A subregion. The presence of Ir-genes outside the H-2 was also suspected. Concerning the production of anti-T3 antibodies, only three strains (B10.A, C3H.SW, BALB/cJ) were high responders and therefore we were unable to identify the Ir-gene for them. These results indicate the presence of Ir-gene which controls the immune response in mice against thyroid hormone and suggest that the anti-thyroid hormone antibodies observed in various thyroidal and non-thyroidal disorders could be anti-HTg antibodies. The significance of genetic control of the production of anti-thyroid hormone antibodies in mice immunized with HTg is discussed.

Animals↗
PubMed1985

[Comparative studies on immunological property of thyroglobulins obtained from the thyroid tumor and the adjacent tissue].

The immunological properties of thyroglobulins (Tg) of individual patients, obtained from a thyroid tumor and its adjacent tissue were compared, using conventional or monoclonal antibodies against human Tg. The thyroid tumors studied were non-functioning thyroid carcinomas and functioning thyroid adenomas. In contrast to non-functioning tumors, Tg from the functioning tumors was generally iodinated at a level close to that of normal tissue, and Tg from the tissue adjacent to the tumors had a very low iodine content. The conventional antiserum and monoclonal antibodies, B2F, seemed to recognize the conformation of Tg, while C6G showed a high affinity to Tg even when unfolded or denatured. In most cases, Tg isolated from the tissue adjacent to a tumor showed a higher affinity to antibodies than Tgs of the tumor tissue, as determined by the inhibitional effect of these Tgs against the binding of standard Tg and antibody. Furthermore, the Tg of the adjacent tissue was immunologically different in nature from the standard Tg obtained from a normal thyroid gland. From these results, Tgs of tumor and the adjacent tissue in individual patients were heterogeneous in immunological property, regardless of iodine content.

Adenocarcinoma↗
PubMed1985

[Investigations on the mechanism(s) of the production of anti-thyroid hormone antibodies 4: the effect of adjuvant on the immune response to human thyroglobulin].

Forty-five female DDYK mice were divided into three groups and immunized with different preparations of human thyroglobulin (HTg). Group 1 mice were immunized subcutaneously in the back with HTg emulsified with FCA. Group 2 mice were immunized subcutaneously in the back with HTg dissolved in PBS. Group 3 mice were immunized with HTg dissolved in PBS and FCA separately in the right (HTg) and left (FCA) of the back. After the fourth immunization (45 days after the first immunization), antisera as well as thyroid glands were obtained, and titers of anti-HTg, anti-T3, anti-T4 and the presence of lesions of autoimmune thyroiditis were examined. In group 1 mice, titers of anti-HTg and anti-T4 antibodies were significantly higher than those of the other two groups, whereas titers of anti-T3 antibodies were significantly lower than those of the other two groups. In group 1 mice, a significant correlation between titers of anti-T3 and anti-T4 antibodies was observed, whereas in group 2 and group 3 mice, no such correlation was observed. The incidence of lesions of autoimmune thyroiditis was significantly higher in group 2 and group 3 mice than in group 1 mice. Thus emulsification of HTg with FCA had inhibitory effects on the induction of experimental thyroiditis in mice immunized with HTg. These results indicate the possibility that FCA has a modulatory effect both quantitatively and qualitatively on the immune response against HTg in mice.

Animals↗
PubMed1985

[The immunochemical properties of thyroglobulin in human thyroid tumors in reaction to rabbit anti-human normal thyroglobulin-serum].

Interactions between antiserum (rabbit anti-human normal thyroglobulin-serum) and human thyroglobulin preparations (obtained from the tissues of the normal thyroid gland, thyroid adenoma, and carcinoma) were compared by inhibition effect with the binding between 131I-labeled standard thyroglobulin and antiserum, set up by a double antibody RIA. Thyroglobulins isolated from normal glands (designated as Nor-Tg) have a high affinity to the antiserum. In contrast, thyroglobulins in follicular adenoma or adenomatous goiter (designated as Ad-Tg) decrease the potency of the affinity to the antiserum. Furthermore, thyroglobulins in papillary or follicular carcinoma (designated as Ca-Tg) markedly decrease such a potency. With the t-test, the inhibition curves of Nor-Tgs are almost parallel to each other. Most of the inhibition curves of Ad-Tgs and Ca-Tgs are not parallel to the curve of Nor-Tg 1 (P-value for non-parallelism less than or equal to 0.05). Therefore, it seems that Tg preparations obtained from tumor tissue are heterogeneous in terms of specificity and/or affinity to antiserum, judging from the results of the non-parallel inhibition curves. The present results also show that the contribution of iodine content in Tg has little or no effect on the nature of Tg-immunogenicity.

Adenoma↗
PubMed1985

Phosphorylated high mannose-type and hybrid-type oligosaccharide chains of human thyroglobulin isolated from malignant thyroid tissue.

Structures of anionic oligosaccharides released by endo-beta-N-acetylglucosaminidase H from human thyroglobulin (19 S) purified from normal and malignant (papillary carcinoma) thyroid tissues were studied by sequential exoglycosidase digestion and lectin affinity chromatography. It was revealed that sialylated hybrid-type oligosaccharides were present in thyroglobulin from normal thyroid tissue, whereas, in the case of thyroglobulin from malignant thyroid tissue, phosphorylated high-mannose type and hybrid-type oligosaccharides each containing one phosphate group in a diester linkage were present instead of sialylated oligosaccharides. The possible meaning of the phosphorylated oligosaccharides was discussed in relation to the low thyroglobulin content in malignant thyroid tissue.

Acetylglucosaminidase↗
PubMed1985

An improved assay method for thyroid peroxidase applicable for a few milligrams of abnormal human thyroid tissues.

A peroxidase assay method (Mini assay method) which is applicable for a minute amount (as small as a few mg) of thyroid tissue was developed, employing guaiacol or iodide as the second substrate. This method is a modification of the previous one (Ordinary assay method): the volume of the reaction mixture was reduced to about one-tenth with prior solubilization of the enzyme. The correlation between the Mini assay and Ordinary assay methods, and between the guaiacol and iodide assays by both methods were satisfactorily good, but the iodine content of thyroglobulin was found to be not directly correlated to the peroxidase activities. Protein-based specific activities of peroxidase from normal human thyroid tissue were about 0.030 guaiacol units/mg protein and 0.0066 iodide units/mg protein, which were slightly higher than those of porcine thyroid tissue. The Mini assay method developed in the present study was used for the determination of peroxidase activity in a small amount (1-8 mg) of thyroid tissue obtained by means of a needle biopsy from patients with thyroid disorders. One specimen (goitrous cretinism) showed no peroxidase activity in both the guaiacol and iodide assays, and three specimens (two chronic thyroiditis, one familial nontoxic goiter) possessed no ability to catalyze the oxidation of iodide in spite of the high reactivity towards guaiacol, suggesting the presence of an abnormal peroxidase in these tissues.

Animals↗
PubMed1985

Properties of thyroglobulins from normal thyroid and thyroid tumor on a concanavalin A-sepharose column.

Affinity chromatography on a concanavalin A (con A)-Sepharose column is a potentially useful for the isolation of whole thyroglobulin (Tg) at least from normal thyroid tissue. In addition to being a simple procedure for the isolation of Tg, large amounts of Tg can be applied to the column and recovered in good yield with a buffer containing MeG. In gradient elution with buffer containing increasing amounts of MeG, a single but broad peak was obtained, without separation into subfractions. However, a hemagglutination-inhibition test showed that the Tg preparation eluted early from the column had less affinity for con A than the Tg preparation eluted later, suggesting a heterogeneous distribution of carbohydrate moieties among Tg preparations. When human Tg from thyroid tumor was applied to the column, tumor Tg partly passed through the column without being adsorbed. This unadsorbed Tg showed a very low affinity for lectins, con A and wheat germ agglutinin (WGA), as determined by a double diffusion reaction in agar gel. In contrast to this fraction, the Tg adsorbed on the con A-gel column showed a very strong affinity for WGA, differing from Tg of normal thyroid tissue. Therefore, tumor Tg preparation appears to have an abnormally modified carbohydrate structure, at least in part. The higher affinity for WGA (with a specificity for N-acetylglucosamine) seen in adsorbed Tg could be due to a larger amount of GlcNAc residues which bind irregularly in the carbohydrate moiety of tumor Tg.

Adenoma↗
PubMed1985

Monoclonal antibodies to thyroglobulin elucidate differences in protein structure of thyroglobulin in healthy individuals and those with papillary adenocarcinoma.

Monoclonal antibodies specific for human thyroglobulin (Tg) from normal subjects were prepared by the hybridoma technique. Antibodies from three clones (clones B2F, C6E, and C6G) were found to produce linear Scatchard plots, as predicted for homogeneous antibodies. Based on different patterns of cross-reactivity with Tg from various species, these monoclonal antibodies recognized different determinants on the Tg molecule. Moreover, antibodies from clone B2F bound simultaneously with clone C6E or C6G to Tg. Therefore, antibody from clone B2F must bind to a site on Tg distant from those recognized by clone C6E or C6G. The monoclonal antibodies C6G and C6E bound almost equally to normal Tg and Tg from patients with Graves' disease, adenoma, follicular carcinoma, and papillary adenocarcinoma. In contrast, whereas clone B2F bound equally well to normal Tg and Tg from patients with Graves' disease, adenoma, and follicular carcinoma, this clone bound poorly to Tg from patients with papillary adenocarcinoma. Since the binding activity of clone B2F for unfolded or degenerated Tg was remarkably decreased, these differences in binding activities to native Tg may reflect changes in conformation of the Tg molecule. Thus, the results indicate there may be conformational changes in Tg from patients with different thyroid diseases.

Adenocarcinoma, Papillary↗
PubMed1985

Interspecies cross-reactive determinants of thyroglobulin recognized by autoantibodies.

In this study, we have attempted to characterize the epitopes of thyroglobulin (Tg) recognized by autoantibodies. Anti-autologous Tg from the serum reacted with other Tg from whales, pigs, cows, chickens and rats as well as with human Tg, thereby indicating that human Tg share epitopes recognized by autoantibodies with Tg from various animal species.

Adolescent↗
PubMed1985

Comparative study of the oligosaccharides of human thyroglobulins obtained from normal subjects and patients with various diseases.

Asparagine-linked oligosaccharides were released quantitatively by N-oligosaccharide glycopeptidase (almond) digestion from human thyroglobulins prepared from thyroid glands of normal subjects and patients with several pathological conditions. The pyridylamino derivatives of the oligosaccharides were prepared and analyzed by high-performance liquid chromatography. The content of high-mannose-type oligosaccharides was comparable to that of the complex type in normal thyroglobulins. Man9GlcNAc2 was the predominant component in the high-mannose-type region, while biantennary oligosaccharides with fucose were the major components in the complex-type region. High-mannose-type oligosaccharides were markedly decreased in thyroglobulins prepared from patients with various disorders, such as Basedow's disease, papillary carcinoma, and adenomatous goiter, whereas they were appreciably increased in thyroglobulin from diffuse goiter.

Adenoma↗