Graves' immunoglobulins activate phospholipase A2 by recognizing specific epitopes on thyrotropin receptor

Thyroid-stimulating IgG from Graves' patients bind to the TSH receptor and activate both adenylyl cyclase (AC) and phospholipase A2 (PLA2) in FRTL5 thyroid cells. Both activities have been associated with increased thyroid cell growth and function; evidence exists that subpopulations of Graves' IgG can stimulate either AC or PLA2 cascades and that the activation of both is associated with the largest goiters in patients. Studies using chimeras of the human TSHR receptor (hTSHR) and the LH-CG receptor show that most patients with Graves' disease have cAMP-stimulating IgG that require epitopes on the N-terminal portion of the TSHR extracellular domain; epitopes associated with PLA2 activation are not clear. To address this question we used stably transfected Chinese hamster ovary (CHO) cells containing the wild-type hTSHR and the hTSHR chimera with residues 8-165 (Mc1+2) substituted by equivalent residues of the LH-CG receptor. PLA2 activity, measured as arachidonic acid (AA) release, was determined in 32 patients with Graves' disease. We show that 72% of Graves' patients have IgG able to stimulate PLA2 in CHO cells transfected with the TSHR and that AA release induced by Graves' IgG was significantly reduced (P = 0.022) in the CHO-Mc1+2-transfected cells (193 +/- 88% vs. 131 +/- 67%, respectively). Unlike IgG, the effect of TSH was not modified in the CHO-Mc1+2-transfected cells. When we compared the AC- and PLA2-stimulating activities of these 32 IgG in wild-type TSHR transfectants, we found that 63% of Graves' patients have antibodies able to stimulate both PLA2 and AC, whereas some patients' IgG were active only in AC or PLA2 assays. Of the patients with IgG having activity in both assays in wild-type TSHR transfectants, 50% of the IgG lost their stimulatory activities in both AA release and cAMP assays in Mc1+2 cells. Of the remainder, some IgG maintained their activity in one (AA release) or the other (cAMP) assay when measured in Mc1+2 chimeras. Thus, our data show that the N-terminal portion of extracellular domain of the TSHR is required for PLA2 as well as AC activation by IgG from patients with Graves' disease. These data also demonstrate that patients with Graves' disease have heterogeneous autoantibodies that selectively activate AC and PLA2 pathways and suggest that patients with autoantibodies active in both assays have more severe disease, with higher thyroid hormone levels and larger goiters.

Selective binding of thyrotropin receptor autoantibodies to recombinant extracellular domain of thyrotropin/lutropin-chorionic gonadotropin receptor chimeric proteins

The extracellular domain of the glycosylated human thyrotropin receptor (ET-gp) contains epitopes that can adsorb pathogenic antibodies from sera of patients with Graves' disease (GD). In an attempt to define the regions within the ETSHR with which autoantibodies interact, we expressed extracellular domains of eight thyrotropin receptor/chorionic gonadotropin receptor (TSHR/LH-CGR) chimeric proteins in insect cells. The levels of expression were high and chimeric proteins were glycosylated. Chimeric proteins designated as EMc2+4 and EMc2+3+4, in which amino acids (aa) 90-165 and 261-370, and aa 90-370, respectively, of TSHR were replaced with corresponding aa of LH-CGR, partially reversed the thyrotropin binding inhibitory immunoglobulin (TBII) activity of experimental anti-TSHR antisera (anti-ET-gp). The other six chimeras almost completely reversed the TBII activity of these anti-ET-GP antisera. Next, we tested the ability of these chimeric proteins to reverse the TBII activity of GD patients' sera. Similar to our earlier study, ET-gp protein reversed the TBII activity of all eight GD patients' sera tested. Chimera EMc2, in which aa 90-165 of TSHR has been replaced with corresponding aa of LH-CGR, and EMc2+4 partially reversed the TBII activity of only three of the eight GD patients' sera. However, the other six chimeric proteins failed to neutralize the TBII activity of any of GD patients' sera. These data showed the following: (1) There is considerable heterogeneity amongst autoantibodies in GD patients' sera, (2) The TBII activity of some, but not others, is dependent on aa 90-165 and 261-370, and (3) Most Graves' sera, with TBII activity, failed to react with chimeric proteins in which either N-terminal or C-terminal regions of the extra cellular domain of the TSHR were replaced with corresponding regions of LH-CGR. These results suggest that the TBII activity of GD patients' sera is dependent on conformational epitopes and replacement of certain regions of TSHR with homologous regions of LH-CGR results in sufficient alteration in the conformation of the protein leading to loss of reactivity.

The heterogeneous expression of MAGE-3 protein: difference between primary lesions and metastatic lymph nodes in gastric carcinoma

We evaluated the expression of MAGE-3 protein in gastric carcinoma by immunohistochemistry, and compared the frequency between primary lesions and metastatic lymph nodes. Primary lesions and metastatic lymph nodes of 38 cases of gastric carcinoma were analyzed using anti-MAGE-3 monoclonal antibody. Expression of MAGE-3 protein was detected in 17 (45%) primary lesions and 12 (32%) metastatic lymph nodes of 38 cases. In 70% of positive cases of primary lesions, the percentage of stained cells with MAGE-3 decreased in metastatic lymph nodes. The heterogeneous expression of MAGE-3 should be considered when we perform antigen specific immunotherapy for patients with gastric carcinoma.

Effect of smoking and histological gastritis severity on the rate of H. pylori eradication with omeprazole, amoxicillin, and clarithromycin

BACKGROUND

The combination of omeprazole, amoxicillin, and clarithromycin is a common regimen against Helicobacter pylori. Several recent studies have shown that smoking, high intragastric acidity, and the degree of histological gastritis are associated with H. pylori eradication failure.

MATERIALS AND METHODS

One hundred and thirty-seven H. pylori-positive patients were treated with a 1-week regimen composed of omeprazole, 20 mg once daily; amoxicillin, 500 mg; and clarithromycin, 200 mg thrice daily. Success of the treatment was evaluated by histology and the 13C-urea breath test at least 4 weeks after completion of therapy. Data about age, gender, alcohol intake, smoking habits, and previous proton pump inhibitor intake were collected in patient interviews. We evaluated fasting gastric pH and the degree of histological gastritis before eradication of H. pylori.

RESULTS

The overall eradication of H. pylori at 4 weeks was successful in 98 of 137 patients (72%). On the multivariate analysis, a low grade of inflammation in the antrum (p </=.01; 95% confidence interval [CI], 2.34-16.75), low grade of activity in the fundus (p </=.05; 95% CI, 1.31-9.65), and smoking (p </=.05; 95% CI, 1.27-6.82) were the significant independent factors predicting treatment failure.

CONCLUSIONS

These findings indicate that H. pylori eradication therapy with omeprazole, amoxicillin, and clarithromycin is less effective in patients who smoke and more effective in patients with high scores of antral inflammation and fundal activity at baseline biopsy.

Identification of a MAGE-2-encoded human leukocyte antigen-A24-binding synthetic peptide that induces specific antitumor cytotoxic T lymphocytes

Because MAGE-2 gene is expressed in a wide variety of malignant tumors and HLA-A24 is the most common allele in the Japanese population and is also frequently present in Caucasians, the identification of MAGE-2-encoded peptide presented by HLA-A24 is, therefore, considered to be important in order to develop specific immunotherapy for malignant tumors using peptides as a vaccine. By using a MHC-binding assay, eight peptides derived from MAGE-2 were found to bind with sufficient affinity to the HLA-A24 molecule. When the induction of specific cytotoxic T lymphocytes (CTLs) was examined using a simplified method, the highest human lymphocyte antigen (HLA) binder (EYLQLVFGI) in these peptides was able to elicit CTLs from unseparated peripheral blood mononuclear cells in HLA-A24 healthy donors by stimulation with freshly isolated, peptide-pulsed peripheral blood mononuclear cells as antigen-presenting cells and also by using interleukin 7 and keyhole-limpet hemocyanin in a primary culture. The induced CTL could, thus, lyse HLA-A24 tumor cells expressing MAGE-2, as well as the peptide-pulsed target cells, with antigen specificity in a HLA class I-restricted manner. The identification of this peptide may, thus, be of therapeutic value in peptide-based vaccines for the treatment of several types of malignant tumors expressing MAGE-2.

Generation of specific antitumor reactivity by the stimulation of spleen cells from gastric cancer patients with MAGE-3 synthetic peptide

The induction of cytotoxic T lymphocytes (CTL) from peripheral blood mononuclear cells (PBMC) using MAGE peptide has been investigated in order to use MAGE antigens immunotherapeutically. We therefore developed a simplified method for inducing peptide-specific CTL that kill tumor cells expressing MAGE from the PBMC of either healthy donors or even cancer patients. Since the spleen is a major lymphoid organ, we used a simple method to examine the capacity of spleen cells to generate MAGE-specific CTL by in vitro stimulation with MAGE peptide in gastric cancer patients. The CTL responses could thus be induced from unseparated spleen cells in HLA-A2 patients with gastric carcinoma expressing MAGE-3 by stimulating these cells with autologous spleen cells pulsed with HLA-A2-restricted MAGE-3 peptide as antigen-presenting cells and by using keyhole limpet hemocyanin and interleukin-7 for the primary culture. The induced CTL were thus able to lyse HLA-A2-positive carcinoma cells transfected with MAGE-3 and expressing MAGE-3, as well as the target cells pulsed with the peptide, in an HLA-class-I or -A2-restricted manner. Since MAGE-specific CTL could be induced from the spleen cells of gastric cancer patients, the spleen appears to play an important role in either clinical tumor vaccination or the treatment of cancer patients by adoptive immunotherapeutic approaches using the MAGE peptide.

[Correlation of serum IgA levels with serum IgG levels, erythrocyte sedimentation rate and platelet counts in 98 patients with rheumatoid arthritis]

Rheumatoid arthritis (RA) is an autoimmune disease with unknown etiology. Polyclonal B cell activation (PBA) is one of immunological abnormalities commonly found in RA patients. We examined serum IgG, IgA, IgM levels in 98 RA patients and compared 31 patients with high serum IgA levels (group B) with 67 patients with normal serum IgA levels (group A) in clinical background. Group B patients had significantly higher mean values of serum IgG levels, erythrocyte sedimentation rate (ESR), and platelet counts than group A. However, there was no correlation between serum IgA levels and X-ray stage, class of ADL or disease duration of RA. These results indicate that high serum IgA levels reflect for disease activity of RA. Serum IgA levels did not correlate with interleukin (IL)-6 levels in 53 RA patients studied. It is speculated that high serum IgA levels might be caused by the following evidences 1) that transforming growth factor (TGF) beta, a known cytokine to increase IgA production by human splenic B cells, gene expression is enhanced in mononuclear cells from synovial fluid and 2) that iron deposition is found in RA synovial and high serum IgA levels are found in iron overload like thalassemia intermedia.

[A case of systemic lupus erythematosus associated with severe acute pancreatitis]

A 22-year-old woman began to have the symptoms of anorexia, high fever, cough and general fatigue from June of 1997. She was admitted in our hospital on Aug. 8th, 1997 for the further detail examination because of pancytopenia and positive antinuclear antibody (ANA). Her laboratory findings and clinical symptoms were compatible with systemic lupus erythematosus (SLE) such as leukopenia, proteinuria, hypocomplementemia, positive ANA, elevated titer of autoantibodies including anti-DNA, anti-Sm, anti-RNP antibodies, polyarthralgia and photosensitivity. The administration of oral prednisolone (40 mg/day) was started on Aug. 15th, 1997 under the diagnosis of SLE. However, she had severe abdominal pain in epigastrium with elevated serum amylase, ascites and dull shape of pancreas tail by CT scan compatible with acute pancreatitis. On Aug. 18th, her general condition was worsening with fever, epigastralgia, abdominal distension, anemia, weak palpation of radial artery, hypotension, tachycardia, shallow breathing and cold sensation on both extremities as shock. In spite of steroid pulse therapy with nafamostat mesilate intraarterial infusion, her condition was not improved. The dose of 50 mg/day of cyclophosphamide was added to the regimen on Aug. 22nd. Then, gradually her condition started to be restored. Anemia, leukopenia, hypocomplementemia continued. Second steroid pulse therapy was done on Sep. 5th. After then, she became better in her clinical symptoms and laboratory data. The dose of PSL was tapered to 15 mg/day and 7.5 mg/day update of Oct. 1998 without the pseudcysts found after pancreatitis. She is a rare case who recovered from severe acute pancreatitis due to SLE itself.

Epitope heterogeneity of thyrotropin receptor-blocking antibodies in Graves' patients as detected with wild-type versus chimeric thyrotropin receptors

The stable transfectants of wild-type (W25) and mutant thyrotropin-receptor (TSH-R) allow detection of the bioactivities of TSH-R antibodies in Graves' patients. A mutant Chinese hamster ovary (CHO) cell line (Mc1+2) transfected with a chimeric construct, where residues 8 to 165 of the TSH-R are replaced with residues 10 to 166 of the lutropin/choriogonadotropin (LH/CGR) receptor, lacks the cyclic adenosine monophosphate (cAMP) response to most thyrotropin stimulating antibodies (TSAb), yet retains the response to TSH and acquires the response to LH/CG. We compared Mc1+2 cells with wild-type W25 cells for their ability to detect TSAb as well as thyrotropin-blocking antibodies (TBAb) in Graves' sera. Eighteen normal and 39 Graves' sera were tested for TSAb and TBAb levels by in vitro bioassays using W25 and Mc1+2 cells. In addition, these sera were also tested for thyrotropin-binding inhibitory activity (TBII) by a radioreceptor assay. Eighteen (47%) Graves' sera had TBAb activity measured with W25 cells but not with Mc1+2 cells. These TBAbs were, therefore, a population of antibodies with functional epitopes on the N-terminus of the extracellular domain. This TBAb activity by W25 cells exhibited a high degree of correlation with TBII levels by a radioreceptor assay (r = 0.70, p = 0.001). Ten (25.6%) Graves' sera had positive TBAb activity in both W25 and Mc1+2 cells; moreover, their activity in both assays was similar (r = 0.83, p < 0.001). The TBAb activity in these sera, however, did not correlate with TBII activity. Eleven (28%) Graves' sera had no TBAb activity. Overall, thyroid-stimulating antibodies were detected in 87% and 28% of the 39 Graves' sera by W25 and Mc1 +2 cells, respectively. Thus, using the 2 cell lines, at least 2 distinct populations of TBAbs were detected. One is detected in a similar fashion by both W25 and Mc1+2 cell lines and likely interacts with the epitopes residing in the unaltered C-terminus of the TSH-R. The other is reactive in W25 cells only, indicating the loss of TBAb epitope in the chimeric receptor located in the N-terminus of the TSH-R. Furthermore, our results indicate that the TBAb binding epitope in 8-165 residues of the native TSH-R is highly associated with TBII activity in Graves' disease. These results indicate that patients with Graves' disease harbor TBAbs with epitope heterogeneity and favor the notion that there are different sites and mechanisms by which TBAbs act in Graves' patients. It remains to be determined whether or not TBAb subtyping will have a useful predictive role in the management of patients with Graves' disease.

Neuropeptide Y Y1 receptor polymorphism as a prognostic predictor in Japanese patients with IgA nephropathy

BACKGROUND

Neuropeptide Y exhibits a vasoconstricting action and regulates systemic blood pressure as well as noradrenalin. There are 5 types of NPY receptors, Y1 - Y5, which were introduced by pharmacological differences. Recently, a single point mutation in the first intron of the NPY Y1 receptor (NPYY1R) was reported.

SUBJECTS AND METHODS

In this study, we investigated the relationship between NPYY1R gene polymorphism and clinical characteristics in patients with IgA nephropathy using polymerase chain reaction and restriction fragment length polymorphism analysis.

RESULTS

Distribution of the NPYY1R genotypes which were defined as YY, Yy and yy genotypes, did not differ between 60 normal control subjects and 68 patients with IgA nephropathy (15 : 36 : 9 versus 21 : 40 : 7, respectively). In IgA nephropathy patients, the incidence of hypertension and the rate of urinary protein excretion were slightly higher in the non-YY genotype than in the YY genotype group (23% versus 5% and 1.1 +/- 1.2 versus 0.6 +/- 0.4 g/24 h, p = 0.09 and p = 0.05, respectively). The reciprocal of the serum creatinine level was estimated to determine the deterioration in renal function during follow-up after the renal biopsy. The level was lower in the non-YY genotype than in the YY genotype group (-0.002 +/- 0.064 vs 0.033 +/- 0.053/month, respectively, p < 0.01). Multiple regression analysis for the reciprocal of the serum creatinine level revealed that the NPYY1R genotype was an effective variable (p < 0.01).

CONCLUSION

In conclusion, we propose that the NPYY1R gene polymorphism may be a novel prognostic predictor in patients with IgA nephropathy.

Expression of the MAGE gene family in human hepatocellular carcinoma

BACKGROUND

The 12 members of the MAGE gene family encode tumor specific antigens that are recognized by autologous cytotoxic T lymphocytes (CTL). The MAGE genes are expressed not only in melanoma but in the other malignant tumors as well. There is, however, little information on their expression in hepatocellular carcinoma (HCC). The authors thus studied the expression of the MAGE gene family in human HCC and discuss the possibility of specific immunotherapy using MAGE peptides.

METHODS

Tumor tissue samples of HCC and paired nontumor tissues of the liver were obtained from 22 HCC patients. Total RNA was extracted and cDNA was synthesized. Polymerase chain reaction amplification using each MAGE gene specific primer was then performed to detect the expression of each MAGE gene. Immunoblotting and immunohistochemical analysis were performed to confirm the expression of MAGE-3 gene product in HCC.

RESULTS

The expression rate of each MAGE gene was as follows: MAGE-1 and -3 were expressed in approximately 68% of the tumors; MAGE-8 was expressed in 46%; and MAGE-2, -6, -10, -11, and -12 were expressed in approximately 30%. Nineteen (86%) of 22 tumors expressed at least 1 MAGE gene. On the other hand, no expression was detected in the noncarcinomatous liver tissue specimens. Actual expression of the gene product of MAGE-3 was detected in 50% of tumors. Clinicopathologic data on the MAGE positive and negative cases were compared. Significant differences were observed between MAGE expression status and a few clinicopathologic factors; however, further investigation is required to elucidate these correlations completely.

CONCLUSIONS

These findings demonstrated that MAGE gene expression is frequent in HCC, thus suggesting that HCC patients may be good candidates for specific immunotherapy using MAGE peptides.

[Photostimulation that induces flattening of photopic electroretinograms--first report. An apparatus for slope photostimulation]

PURPOSE

We developed a new photostimulation system for electroretinograms (ERGs). This apparatus is capable of varying the transients during stimulus on and off (up-slope and down-slope times, respectively) as well as the stimulus and background intensities. We applied this system to evaluate the photopic ERG in human eyes.

CASES AND METHODS

Seven normal volunteers and a 43-year-old patient with pre-proliferative diabetic retinopathy served as test subjects. We recorded ERGs with relatively long intervals of up-slope and down-slope times for photostimulation.

RESULTS

As the up-slope and down-slope times were increased, the amplitude was reduced and the peak latency was prolonged for both the on and off responses. When the normal subjects' retinas were stimulated with a 341-msec up-slope time and a 34.1-msec down-slope time, the ERG waves showed complete flattening in both on and off responses. The ERGs of a patient with pre-proliferative diabetic retinopathy showed much longer peak latency than that of the normal volunteers as the up-slope time was prolonged. When the patient's retina was stimulated for a prolonged up-slope time, the average of the amplitude of ERG waves was similar to that of the normal volunteers.

CONCLUSION

These results suggest that this new type of photostimulation might potentially uncover some novel aspect of clinical ERGs and might be useful for testing retinal functions of patients with diabetic retinopathy.

Two Graves' disease patients who spontaneously developed hypothyroidism after antithyroid drug treatment: characteristics of epitopes for thyrotropin receptor antibodies

Few reports have identified blocking thyrotropin receptor antibodies (TSHRAbs) as a pathogenic mechanism explaining spontaneous hypothyroidism after antithyroid drug (ATD) treatment of Graves' disease. Here we report 2 Graves' patients who showed different courses of hypothyroidism after ATD treatment. The first patient had Graves' hyperthyroidism and was treated with ATD for 1 year. After a short period of euthyroidism, she developed permanent hypothyroidism with blocking TSHRAb. The second patient became euthyroid after 1 year of ATD treatment. After 3 years, however, she presented with hypothyroidism with blocking TSHRAb activity. Her hypothyroidism was transient, and restoration of euthyroidism was followed by disappearance of blocking TSHRAb. Blocking and stimulating TSHRAbs activities of these 2 patients were serially measured using Chinese hamster ovary (CHO) cells transfected with wild-type human TSHR (CHO-hTSHR) and 2 TSHR chimeras with residues 8-165 (Mc1+2) or 90-165 (Mc2) substituted by equivalent residues of the luteinizing hormone/chorionic gonadotropin receptor (LH/CGR). During their hypothyroid phases, blocking TSHRAbs activities were positive in all 3 kinds of assays and stimulating TSHRAbs activities were negative in CHO-hTSHR or in Mc 1+2 assay. Mc2 stimulating TSHRAb activity was detected in sera of hypothyroid phase of the second patient who had transient hypothyroidism but not in the first whose hypothyroidism was permanent. In these 2 cases, we demonstrate the causative role of blocking TSHRAb in the development of hypothyroidism after ATD treatment in Graves' patients. Interestingly, the difference in the course of blocking TSHRAb-induced hypothyroidism was associated with the difference in epitope reactivities of TRAb during hypothyroid phase that developed after ATD treatment of Graves' disease.

Daily positioning accuracy of frameless stereotactic radiation therapy with a fusion of computed tomography and linear accelerator (focal) unit: evaluation of z-axis with a z-marker

To evaluate quantitative positioning errors of frameless stereotactic radiation therapy with a fusion of computed tomography (CT) and linear accelerator unit, Z-type CT markers were attached to patients, and CT images were obtained before and after daily treatment. In 40 verification tests, geometrical errors were never more than 1 mm.

A MAGE-1-encoded HLA-A24-binding synthetic peptide induces specific anti-tumor cytotoxic T lymphocytes

Although several MAGE-1 peptides have already been identified, the MAGE-1-encoded peptide presented by HLA-A24, which is the most common allele in Japanese population and is also frequently present in Caucasians, might have a wide applicability for immunotherapy using these peptides. To identify this potential peptide, we examined the induction of specific cytotoxic T lymphocytes (CTL) from the peripheral-blood mononuclear cells (PBMC) in HLA-A24 healthy donors by in vitro stimulation with MAGE-1-encoded synthetic peptides with a binding affinity for HLA-A24, by a simplified method. Of the 5 peptides tested, the highest HLA binder (NYKHCFPEI) was able to elicit CTL from unseparated PBMC by stimulation with freshly isolated, peptide-pulsed PMBC as antigen-presenting cells (APC) and by also using interleukin 7 and keyhole-limpet hemocyanin for a primary culture. The induced CTL could thus lyse HLA-A24 tumor cells expressing MAGE-1, as well as the peptide-pulsed target cells, in an HLA-class-I-restricted manner. By using the MAGE-1/HLA-A24 peptide, NYKHCFPEI, we found it possible to immunize many more patients, especially Japanese patients, by means of such peptide-based immunotherapeutic approaches to MAGE-1-positive malignant tumors.

[Anti-myeloperoxidase and anti-lactoferrin antibodies in patients with IgA nephropathy and Henoch-Schönlein purpura]

Antineutrophil cytoplasmic antibodies (ANCA) for two antigens, i.e. myeloperoxidase (MPO) and lactoferrin (LF) in sera from 19 IgA nephropathy (IgAN), 3 adult Henoch-Schönlein purpura (HSP) and 8 child HSP patients were examined by enzyme-linked immunoabsorbent assay (ELISA) for immunoglobulin isotypes. All of child HSP patients showed negative ANCA. On the other hand, one IgAN patient and two adult HSP patients showed weak positivity for IgA class anti-MPO antibody. There was no patients who showed positivity for IgG and IgM class anti-MPO antibody. In anti-LF antibody, one IgAN and one adult HSP showed positivity in IgG class; 2 IgAN and 2 HSP in IgA class and 2 IgAN and one HSP in IgM class. These results indicate that adult HSP patients have higher prevalence of IgA class anti-MPO antibody and anti-LF antibody than IgAN or child HSP.

[A case of secondary systemic amyloidosis associated with rheumatoid arthritis after 3-year disease duration]

A 63-year-old woman who started to have polyarthralgia in December 1993 has been diagnosed as rheumatoid arthritis (RA) and treated with muscular injection of gold sodium thiomalate. She began to have nausea, vomiting, anorexia and watery diarrhea in October 1995. A year later, she had to receive intravenous infusion on admission since more frequent watery diarrhea occurred more than ten times within a day. On admission in our hospital in December 1996, she had proteinuria in addition to gastrointestinal symptoms. The biopsy specimen from stomach, duodenum and kidney proved systemic amyloidosis associated with RA. In spite of steroid-pulse, dimethyl sulfoxide (DMSO) and colchicine therapy, profound proteinuria in nephrotic syndrome was continued in association with hypoproteinemia, anasarca and renal failure. She was treated on hemodialysis and intravenous hyperalimentation (IVH) until November 1997 when A-V shunt operation on left forearm was performed. However, the shunt was not available for HD and she suffered from septicemia and died on December 1997. This patient was a rare case of secondary systemic amyloidosis associated with RA in early clinical course.

A MAGE-1-encoded HLA-A24-binding synthetic peptide induces specific anti-tumor cytotoxic T lymphocytes

Although several MAGE-1 peptides have already been identified, the MAGE-1-encoded peptide presented by HLA-A24, which is the most common allele in Japanese population and is also frequently present in Caucasians, might have a wide applicability for immunotherapy using these peptides. To identify this potential peptide, we examined the induction of specific cytotoxic T lymphocytes (CTL) from the peripheral-blood mononuclear cells (PBMC) in HLA-A24 healthy donors by in vitro stimulation with MAGE-1-encoded synthetic peptides with a binding affinity for HLA-A24, by a simplified method. Of the 5 peptides tested, the highest HLA binder (NYKHCFPEI) was able to elicit CTL from unseparated PBMC by stimulation with freshly isolated, peptide-pulsed PMBC as antigen-presenting cells (APC) and by also using interleukin 7 and keyhole-limpet hemocyanin for a primary culture. The induced CTL could thus lyse HLA-A24 tumor cells expressing MAGE-1, as well as the peptide-pulsed target cells, in an HLA-class-I-restricted manner. By using the MAGE-1/HLA-A24 peptide, NYKHCFPEI, we found it possible to immunize many more patients, especially Japanese patients, by means of such peptide-based immunotherapeutic approaches to MAGE-1-positive malignant tumors.

[A case of pityriasis rubra pilaris associated with unclassified connective tissue disease and sepsis in clinical course]

The patient was a 23-year-old woman with HTLV-I carrier and was diagnosed as pityriasis rubra pilaris soon after her birth. In November 1990 at her age of 16, she began to have fever and polyarthralgia which were not improved despite the administration of antibiotics. Her laboratory findings showed the positive antinuclear antibody and anti-RNP antibody suggesting one of collagen diseases. A tentative diagnosis as unclassified connective tissue disease (UCTD) was made since her symptoms and laboratory findings were not satisfied with any criteria for rheumatic disorders. The steroid therapy was started in February 1991 and showed a good response. On April 9th, 1996, however, she was admitted to our hospital because of recurrence of high fever and chills. This time, she had sepsis because of the evidence that Enterococcus faecalis was detected in blood culture. Although her condition was improved by antibiotics on June 4th 1996, high fever re-appeared and followed by convulsion and disseminated intravascular coagulation. After the doses of prednisolone per day was increased to 40 mg with antibiotics and anticoagulant, her condition gradually improved. This patient was a rare case of pityriasis rubra pilaris associated with UCTD and sepsis in clinical course.

Down regulation by iron of prostaglandin E2 production by human synovial fibroblasts

OBJECTIVE

To examine the effect of iron on the prostaglandin (PG) E2 production by human synovial fibroblasts in vitro.

METHODS

Human synovial fibroblasts were isolated from synovial tissue of rheumatoid arthritis (RA) and osteoarthritis (OA) patients and cultured in medium. Synovial fibroblasts were stimulated by human recombinant interleukin (IL) 1 beta (0.1-10 ng/ml) with or without ferric citrate (Fe-citrate, 0.01-1 mM). The amount of PGE2 in the culture medium was measured by an enzyme linked immunosorbent assay.

RESULTS

The production of PGE2 by the synovial fibroblasts was increased by stimulation with IL1 beta at all concentrations tested. Fe-citrate but not sodium citrate (Na-citrate) down regulated the production of PGE2 by the synovial fibroblasts, both with and without stimulation by IL1 beta. Fe-citrate inhibited the spontaneous PGE2 production by the cells in a dose dependent manner, and a maximum inhibition by Fe-citrate was observed at the concentration of 0.1 mM with IL1 beta stimulation. The down regulation by iron was reversed by the co-addition of desferrioxamine (100 micrograms/ml), an iron chelator.

CONCLUSION

Iron down regulates the PGE2 production by synovial fibroblasts in vitro.

The significance of atrial monophasic action potentials for monitoring rat cardiac allograft rejection

BACKGROUND

Changes in the monophasic action potential may be used for detecting early acute rejection in the transplanted rat heart.

METHODS

Heterotopic heart transplantations were performed in allogeneic and syngeneic rats. During atrial pacing, monophasic action potentials were simultaneously recorded in the right atrium and ventricle of the transplanted hearts on postoperative days 1, 3, and 5. The amplitude and duration of monophasic action potentials, atrioventricular conduction time, and cardiac intervals were analyzed. Histopathologic examination for rejection was performed on postoperative days 1, 3, and 5.

RESULTS

In the allogeneic group, monophasic action potential amplitude progressively decreased, and monophasic action potential duration gradually increased after heart transplantation in the atrium and ventricle. With rejection, the amplitude decreased to a greater extent, and monophasic action potential duration increased to a greater extent in the atrium than in the ventricle on day 3. The atrioventricular conduction time increased on day 5, but the cardiac interval did not change. An inverse correlation between histopathologic grade and the monophasic action potential amplitude, and a positive correlation between histopathologic grade and the monophasic action potential duration existed for both the atrium and ventricle. These electrophysiologic and histopathologic changes were not observed in the syngeneic group.

CONCLUSIONS

We conclude that right atrial monophasic action potentials may be a useful and reliable indicator of early acute heart transplant rejection.

Severe diabetic scleredema with extension to the extremities and effective treatment using prostaglandin E1

We report a 49-year-old woman with severe diabetic scleredema (DS). The patient had non-insulin-dependent diabetes mellitus (NIDDM) for 9 years and noticed thickened skin on her back 3 years previously. Her DS rapidly extended to her back and extremities with pain and immobility. Her symptoms of DS improved dramatically after establishing strict glycemic control and intravenous administration of prostaglandin E1 (PGE1). However, the histological findings of her skin biopsy did not change even after the treatment for 12 weeks, and her symptoms worsened again after discontinuation of glycemic control and PGE1 treatment. The causes of DS have been considered to be metabolic abnormalities associated with hyperglycemia and hypoxia in the skin due to diabetic microangiopathy. PGE1 was an effective treatment for DS in our patient. Strict control of hyperglycemia and PGE1 treatment may be sufficient to manage DS, although a very long treatment period is necessary.

Thyrotropin receptor epitopes recognized by graves' autoantibodies developing under immunosuppressive therapy

Abnormal modulation of the immune system is a prerequisite for the expression of Graves' disease. Thus, when hyperthyroidism developed in a renal transplant recipient under long term immunosuppression with cyclosporine A and prednisone, we carefully evaluated the basis for her hyperthyroidism and her state of immunosuppression. Immunosuppression was confirmed by finding markedly deficient lymphocyte responses to common mitogens. Lymphocyte phenotype frequencies were those previously found in Graves', i.e. elevated frequencies of CD3/DR, CD5/26, and CD3/25 lymphocytes. There was also reversal of the CD4/CD8 ratio due to increased CD8 frequency; this is not a typical finding in autoimmune hyperthyroidism, but has been seen in the intrathyroidal lymphocyte populations of some Graves' patients and is associated with other forms of autoimmunity. The patient's serum contained a broad spectrum of TSH receptor autoantibodies (TSHRAbs) characteristic of Graves' disease. To determine whether these were an unusual population of autoantibodies, we determined their functional epitopes before and for nearly 1 yr after radioiodine therapy. Stimulating TSHRAbs that increase cAMP levels were human receptor (TSHR) specific and consistently recognized functional epitopes located on TSHR residues 90-165. Stimulating TSHRAbs that increased arachidonate release and inositol phosphate levels recognized residues 25-90, as did TSH binding inhibitory Igs present in the patient. These data demonstrate that Graves' disease with a wide array of TSHRAbs can develop in a patient despite adequate immunosuppression. More importantly, they show that the cAMP-stimulating TSHRAb associated with disease expression in this patient had a homogeneous subtype dependent on TSHR residues 90-165. As persistence of this type of TSHRAb over time has been associated with resistance to methimazole therapy in Graves' patients, we speculate that the development and persistence of TSHRAb with this homogeneous epitope may be linked to resistance to immunosuppressive therapy.