Expression of prostaglandin E synthase mRNA is induced in beta-amyloid treated rat astrocytes

Deposition of beta-amyloid (A beta) in the brain is considered to be one of the most critical events in the onset of Alzheimer's disease (AD). In order to identify factors involved in the exacerbation of AD, we investigated transcriptionally A beta-induced genes using a cDNA subtraction technique in rat astrocytes. One gene obtained was rat prostaglandin (PG) E synthase. In this report, we present the deduced sequence for rat PGE synthase for the first time and demonstrate the induction of PGE synthase mRNA by treatment of cells with A beta. Our results suggest a possibly significant role of this enzyme in the progression of AD.

CD4+CD45RA+ cells (suppressor-inducer T cells) in thyroid tissue from patients with Graves' disease

Previously, we used dual immunofluorescent analysis and showed that the thyroid gland from patients with Graves' disease had a reduced number of CD4+CD45RA+ cells, but an increased number of complementary CD4+CDw29+ cells. An immunohistochemical study, however, produced opposite results; interstitial lymphocytes predominantly expressed the CD45RA+ rather than the CDw29+ phenotype. Because the difference in findings may be due to differences in the techniques used, we did the following experiments: Mononuclear cells were treated with various amounts of collagenase (50-1000 mg/l) which had no effect on the cell surface antigens CD3, CD4 and CD45RA. A dual immunofluorescent study showed that the numbers of CD4+CD45RA+ and CD8+CD45RA+ cell population among CD45RA+ cell population were markedly decreased in the thyroid tissue, and that the CD45RA antigen on the intrathyroidal mononuclear cells was mainly expressed on the CD20+ cells. As the thyroid section had been fixed with acetone before immunohistochemical staining, CD45RA- cells were treated with acetone and stained with anti-CD45RA monoclonal antibody using an avidin-biotin peroxidase complex method. The results of this experiment suggest that there are cell surface molecules which react with anti-CD45RA monoclonal antibody after treatment with acetone in CD45RA- cells. The above findings confirm our previous results which showed that the thyroid glands of patients with Graves' disease have decreased numbers of suppressor-inducer T cells. Also, several problems exist in the detection of CD45RA+ cells when using an immunohistochemical method.

[A case of aortitis syndrome complicated with amyloidosis, type AA]

We recently saw a patient who had aortitis syndrome associated with secondary amyloidosis. To our knowledge, she is the fourth report of this complication occurring in aortitis syndrome. In November 1985, the patient, a 18 year-old woman, was admitted to our hospital because of a high fever, back pain, abdominal pain and general fatigue. On physical examination, bruit was audible on the abdomen, bilateral radial artery was weakly palpable. Angiography showed the stenosis of bilateral carotid artery, subclavian artery, renal artery and superior mesenteric artery. From the above findings, she was diagnosed aortitis syndrome, and treatment was begun with prednisolone. However, she developed recurrently a high fever, chest pain, abdominal pain and exertional dyspnea. Laboratory findings at the active stage revealed the marked elevation of leukocytes, erythrocyte sedimentation rate and C-reactive protein. On her clinical course, the number of circulating thrombocytes was paralleled with the activity of the disease. On June 1988, she developed suddenly a high fever and severe pain of abdomen. Pathological findings of her stomach showed the deposition of amyloid protein A. Laboratory findings depicted the marked increment of thrombocytes, beta-thromboglobulin and platelet factor 4. These results suggest that circulating thrombocytes may play a role in product ion of amyloid protein.

[Spectral analysis of heart rate variability in the dysfunction of the brainstem]

The heart rate variability, modulated by autonomic nervous system, has been reported to decrease in depression of the central nervous system, especially of the brainstem. To assess the brainstem dysfunction, we analyzed R-R interval values (the intervals between R waves of ECG) in 9 children (7 in comatose children and 2 in central apnea) by spectral analysis using an autoregressive model. The findings of spectral analysis were compared with those of auditory brainstem response (ABR). In comatose children with the brainstem dysfunction, the reduction of the total power was apparent before the appearance of ABR abnormality. In central apnea due to the dysfunction of respiratory center in brainstem, only the respiratory component decreased without the reduction of the total power or ABR abnormality. Spectral analysis of the heart rate variability is a useful means for assessment of the brainstem function.

Cytokine regulation of HLA on thyroid epithelial cells

The regulation of class I and class II HLA expression in human thyroid follicular cells was studied in vitro. Tumour necrosis factor-alpha (TNF-alpha) enhanced the expression of class I antigen on thyrocytes, but these cytokines had little effect on the expression of class II antigen. Interleukin-1 beta (IL-1 beta) and interleukin-6 (IL-6) did not affect class I and class II antigen expression. The combination of interferon-gamma (IFN-gamma) with TNF-alpha or IL-1 beta enhanced the induction of class I and class II antigens, compared with the effect of IFN-gamma alone. Neither class I nor class II expression was induced by IL-6 alone or in combination with IFN-gamma. These findings suggest that TNF-alpha and IL-1 beta may have an important role in inappropriate expression of HLA antigens on thyrocytes in thyroid gland.

Inhibitory effects of gold sodium thiomalate on the proliferation and interferon-gamma induced HLA-DR expression in human endothelial cells

Our study was undertaken to investigate the effects of gold sodium thiomalate (GSTM) on the proliferation and HLA-DR antigen expression of human umbilical vein endothelial cells (EC). The proliferation of the EC was determined by 3H-thymidine incorporation into the EC. The expression of HLA-DR antigen on the surface of the EC was detected by an indirect immunofluorescent method using a fluorescent flow cytometer. When GSTM was added at the start of the EC culture, GSTM at a low concentration could inhibit the proliferative response of the EC to endothelial cell growth supplement. Furthermore, when the EC were cultured with recombinant interferon-gamma (rIFN-gamma) and GSTM, GSTM was also able to suppress the HLA-DR antigen expression on the surface of EC induced by rIFN-gamma. On the time-kinetic study of the effects of GSTM on the HLA-DR antigen expression induced by rIFN-gamma, the pretreatment of GSTM was able to suppress the HLA-DR antigen expression, whereas GSTM did not affect the HLA-DR antigen expression already induced by rIFN-gamma. Our findings suggest that the therapeutic effects of gold compounds in patients with rheumatoid arthritis may be attributed to the interference of the proliferation and HLA-DR antigen expression of the EC.

Phenotypic characterization of lymphocytes infiltrating synovial tissue from patients with rheumatoid arthritis: analysis of lymphocytes isolated from minced synovial tissue by dual immunofluorescent staining

The phenotypic markers of mononuclear cells in synovial tissue from 19 patients with active rheumatoid arthritis (RA) were identified by a dual immunofluorescent method. The mononuclear cells were isolated from synovial tissue by mechanical disaggregation and an enzymatic digestion technique. The results revealed a marked reduction in CD4+2H4+ cells (suppressor inducer T cells) and an increment in CD4+4B4+ cells (helper T cells) among CD4+ cells in synovial tissue. The percentage of CD8+CD11b+ cells (suppressor effector T cells) was significantly lower in synovial tissue than in peripheral blood from patients with RA, resulting in an increased percentage of CD8+CD11b-- cells (cytotoxic T cells). The synovial tissue had higher percentages of pan B cells (B1+ cells), differentiated B cells (B1+B2-- cells) and plasma cells (PCA-1+ cells). These findings suggest that a combination of the increment in helper T cells, the reduction in suppressor T cells, and the increment in differentiated B cells may lead to excessive production of autoantibodies.

[Assessment and treatment of respiratory dysfunction in severely handicapped children: respiratory disorders during sleep]

In severely handicapped patients, chronic respiratory insufficiencies and recurrent hypoxemia especially during sleep are one of the major problems to take care of them. To clarify the pathophysiology of respiratory disorders during sleep, we examined 5 severely handicapped patients with no respiratory distress during wakefulness, but with signs of latent respiratory insufficiency by means of polygraphical all-night study including the arterial oxygen saturation (SaO2) monitoring. In the severely handicapped patients, sleep hypoxemia occurred frequently. The value of SaO2 decreased in proportion to the intensity of apnea determined by polygraph. The relationship between the value of SaO2 and sleep stage was variable in each patient. Four patients had mainly obstructive respiratory disorders and one had a central type respiratory disorder. The density of REM stage decreased in the obstructive type. In the central type, the repeat of REM stage with normal REM density was not observed. In one patient with obstructive type and one with central type, hypoxemia was improved with an increased number of REM stage by O2 inhalation.

Abnormal B lymphocyte function in thyroid glands from patients with Graves' disease

Thyroid-infiltrating B lymphocytes from patients with Graves' disease were investigated in regard to their phenotypic profiles, cell size, cell cycle status, proliferative response to Staphylococcus aureus Cowan 1 (SAC), and spontaneous production of immunoglobulin G (IgG) and antithyroidal autoantibodies. Thyroid tissues and peripheral blood were obtained at the time of subtotal thyroidectomy of 27 Graves' patients who had been treated with thionamide drugs and iodide before operation. Two intrathyroidal mononuclear cell populations were obtained from these thyroid tissues. One cell population was isolated from the supernatants after mechanical disaggregation of the tissues and was defined as TG-1 cells. Another cell population, defined as TG-2 cells, was isolated from the supernatants of overnight cultures of the thyroid debris after enzymatic digestion. The percentages of B lymphocytes bearing activated markers and plasma cells (CD20+CD21-, IgM+IgD-, CD20+ transferrin receptor+, PCA-1+) were significantly higher in the TG-1 and TG-2 cell populations than in peripheral blood from Graves' disease patients and normal subjects. These phenotypic changes were accompanied by increased thyroid gland B lymphocyte cell size from patients with Graves' disease. The proliferative response of B lymphocytes to SAC was markedly lower in TG-1 and TG-2 cell populations than in peripheral blood cells from Graves' disease patients and normal subjects. B lymphocytes isolated from thyroid glands secreted significantly more IgG and antithyroidal autoantibodies than those from peripheral blood. Based on the findings of abnormalities in thyroid-infiltrating B lymphocytes, we suggest that activated B lymphocytes may induce the excessive production of antithyroidal autoantibodies in thyroid glands from patients with Graves' disease.

Cytotoxic activity of interleukin-2 (IL-2) activated killer cells toward thyroid epithelial cells

We investigated the sensitivity of thyroid epithelial cells (thyrocytes) to IL-2 activated killer cells. The thyrocytes were lysed by autologous and allogeneic IL-2-activated killer cells; there were no differences in sensitivity to the killer cells between normal thyrocytes and thyrocytes from patients with Graves' disease. When thyrocytes were pretreated with recombinant interferon (rIFN) gamma or alpha, the IL-2-activated killer cell-mediated cytotoxicity was depressed and varied inversely with the cell surface expression of class I HLA gene products. The rIFN-gamma pretreatment did not alter the kinetics of thyrocytes lysis by IL-2-activated killer cells. Using cold target competition analysis, rIFN-gamma-pretreated thyrocytes clearly competed less effectively than did untreated cells for lysis of untreated target cells. These results suggest that rIFN-gamma or IFN-alpha pretreatment of thyrocytes may reduce their ability to be recognized by effector cells. These findings suggest that destruction of thyrocytes in autoimmune thyroiditis may be, in part, due to IL-2-activated killer cells and may be regulated by IFN.

[A case of progressive systemic sclerosis accompanied with rheumatoid arthritis]

A 37-year old man was suffered from Raynaud's phenomenon, sclerodactyly, and polyarthritis involving knees, shoulders, and hands. Recurrent skin ulcers were present in finger tips. Laboratory studies showed positive RA test, antinuclear antibody (nucleolar type), and anti-Scl 70 antibody. So diagnosis of progressive systemic sclerosis (PSS) was made. Progressed destructive arthritis with rheumatoid nodules developed in the patient. The joint destruction was severe and he was satisfied with the criteria of the American Rheumatism Association (ARA). This patient appears to be an overlapping case of PSS and rheumatoid arthritis (RA).

Increment in the Ta1+ cells in the peripheral blood and thyroid tissue of patients with Graves' disease

The present study utilized the anti-Ta1 mAb to characterize the cell surface phenotypes of peripheral blood and intrathyroidal lymphocytes in patients with Graves' disease. We found an increase in PBL bearing the Ta1 Ag in untreated patients. The euthyroid patients in remission, induced by antithyroidal drugs, radioisotope therapy, and subtotal thyroidectomy, had lower percentages of Ta1+ cells than did untreated patients. An increased percentage of Ta1+ cells in untreated patients was found in both CD4+ cells and CD8+ cells. The ratio of CD4+Ta1+ cells to CD8+Ta1+ cells in untreated patients was significantly higher than that of normal subjects. There was a positive correlation between the percentage of Ta1+ cells and the level of anti-TSH receptor antibody. In this prospective study, the proportion of Ta1+ cells was decreased in parallel with the reduction in anti-TSH receptor antibody and free T3 levels. In the chronically treated patients, the proportion of Ta1+ cells in the thyroid tissue was, yet similar to that in the peripheral blood, markedly increased in comparison to that of normal subjects. In contrast to Ta1+ cells, the thyroid tissue had a significantly higher percentage of HLA-DR+ T cells than did the paired peripheral blood. The proliferative responses of the Ta1+ cell-enriched population isolated from untreated patients toward thyroglobulin and microsomal Ag were markedly higher than those in a Ta1+ cell-depleted population, but both populations were able to respond equally to PHA. These results suggest that the Ta1+ cells may include Ag-triggered memory cells that are reactive with thyroid-specific Ag. Furthermore, monitoring such cells may provide an objective measure of abnormal immunologic activity.

Increment in the Ta1+ cells in the peripheral blood and thyroid tissue of patients with Graves' disease

The present study utilized the anti-Ta1 mAb to characterize the cell surface phenotypes of peripheral blood and intrathyroidal lymphocytes in patients with Graves' disease. We found an increase in PBL bearing the Ta1 Ag in untreated patients. The euthyroid patients in remission, induced by antithyroidal drugs, radioisotope therapy, and subtotal thyroidectomy, had lower percentages of Ta1+ cells than did untreated patients. An increased percentage of Ta1+ cells in untreated patients was found in both CD4+ cells and CD8+ cells. The ratio of CD4+Ta1+ cells to CD8+Ta1+ cells in untreated patients was significantly higher than that of normal subjects. There was a positive correlation between the percentage of Ta1+ cells and the level of anti-TSH receptor antibody. In this prospective study, the proportion of Ta1+ cells was decreased in parallel with the reduction in anti-TSH receptor antibody and free T3 levels. In the chronically treated patients, the proportion of Ta1+ cells in the thyroid tissue was, yet similar to that in the peripheral blood, markedly increased in comparison to that of normal subjects. In contrast to Ta1+ cells, the thyroid tissue had a significantly higher percentage of HLA-DR+ T cells than did the paired peripheral blood. The proliferative responses of the Ta1+ cell-enriched population isolated from untreated patients toward thyroglobulin and microsomal Ag were markedly higher than those in a Ta1+ cell-depleted population, but both populations were able to respond equally to PHA. These results suggest that the Ta1+ cells may include Ag-triggered memory cells that are reactive with thyroid-specific Ag. Furthermore, monitoring such cells may provide an objective measure of abnormal immunologic activity.

Interleukin-1 production and action in thyroid tissue

This study was undertaken to determine the effects of interleukin-1 (IL-1) on human thyroid epithelial cells (thyrocytes) and whether thyrocytes produce IL-1. The supernatants of cultured peripheral blood monocytes stimulated with lipopolysaccharide (LPS) increased [3H]thymidine incorporation into thyrocytes from normal subjects and patients with Grave's disease. The IL-1 levels of cultured supernatants of monocytes were measured by a thymocyte costimulation assay and a solid phase sandwich immunoenzymometric assay. The supernatants of monocyte cultures stimulated with LPS contained significant amounts of IL-1 bioactivity and IL-1 alpha and IL-1 beta immunoactivity. Recombinant IL-1 beta (rIL-1 beta) also stimulated [3H]thymidine incorporation into thyrocytes from normal subjects and patients with Graves' disease, and it increased the proportion of thyrocytes in the S phase of the cell cycle. Furthermore, thyrocytes stimulated with rIL-1 beta for 24 h produced significant amounts of prostaglandin E2. Indomethacin inhibited completely the rIL-1 beta-stimulated prostaglandin E2 production and increased markedly [3H]thymidine incorporation. IL-1-like activity also was detected in the cultured supernatants of lipopolysaccharide (LPS)-stimulated thyrocytes from Graves' and normal thyroid glands, but the amount of IL-1-like activity secreted by thyrocytes was significantly less than that secreted by circulating monocytes. The kinetics of the release of IL-1-like activity by thyrocytes were similar to those of its production by circulating monocytes. Pretreatment of thyrocytes with interferon-gamma failed to enhance the release of IL-1-like activity. Moreover, IL-1 alpha or IL-1 beta immunoreactivity could not be detected in the supernatants of LPS-stimulated thyrocytes, despite the presence of IL-1-like bioactivity. No IL-1 alpha mRNA was detected in unstimulated thyrocytes or thyrocytes stimulated with LPS and phorbol myristate acid. These findings demonstrate that thyrocytes produce an IL-1-like substance(s), but not IL-1, when stimulated by LPS. We conclude that IL-1 may regulate the proliferation of thyrocytes and that local production of IL-1 by infiltrating monocytes may contribute to the development of goiter in patients with autoimmune thyroid diseases.

Infantile cytochrome c oxidase deficiency with neonatal death

A newborn male presented with severe respiratory insufficiency, generalized muscle weakness, and lactic acidemia. Immediately after admission, he was placed on a respirator because of respiratory arrest. He deteriorated rapidly and died 75 hours after birth. There was notable variation in fiber size and an increased number of type 2C fibers in the quadriceps femoris muscle obtained at autopsy; however, no ragged-red fibers were observed with modified Gomori trichrome staining. Markedly decreased cytochrome c oxidase activity was demonstrated in skeletal muscle by biochemical and histochemical studies, while cardiac muscle demonstrated normal cytochrome c oxidase activity. Mitochondrial myopathy should be considered in the differential diagnosis of patients with neonatal respiratory distress syndrome.

Nemaline myopathy: comparative muscle histochemistry in the severe neonatal, moderate congenital, and adult-onset forms

A histochemical study of biopsied muscle specimens from patients with the 3 forms of nemaline myopathy (i.e., severe neonatal, moderate congenital, and adult-onset), classified on the basis of clinical symptoms, was conducted. A close relationship could not be found between the number of rods and the severity of weakness in any form. Type 1 fiber atrophy and predominance or type 2B fiber deficiency was the usual finding in all forms. In the moderate congenital form, type 1 fiber atrophy and predominance became more apparent in patients with a protracted course, suggesting that the histochemical abnormalities are progressive. The abnormal fiber type distribution is assumed to be related to the pathogenetic mechanism of nemaline myopathy in all forms. Because acid phosphatase activity was increased in muscle fibers of patients with rapid progression, an autodegenerative process inducing lysosomal enzyme activation may be responsible for the acute clinical progression and muscle fiber loss in this disorder.

The effects of cytokines, antithyroidal drugs and glucocorticoids on phagocytosis by thyroid cells

The present study was undertaken to examine whether thyrocytes possess phagocytic activity and whether the phagocytic activity is influenced by cytokines, such as interleukin 1, 2 (IL 1, IL 2) and interferon-alpha, -beta, and -gamma (IFN-alpha, beta, and gamma), and drugs, such as methimazole and dexamethasone. Thyroid glands were obtained from patients with Graves' disease. Thyrocytes were prepared by collagenase digestion. Thyrocytes were pre-incubated in the presence or absence of cytokines and drugs at 37 degrees C for 20 h and were further incubated with fluoresceinated latex beads at 37 degrees C for 60 min. The number of phagocytic thyrocytes was determined by FACS IV. Phagocytosis of latex beads was indeed seen within thyrocytes and gradually increased in a time-dependent manner. The rate of phagocytosis in thyrocytes was extremely slow as compared with that in macrophages. Phagocytic activity was detected in thyrocytes from patients with Graves' disease and from normal thyroid tissue adjacent to thyroid cancer. Phagocytosis was inhibited by IL 1, but was enhanced by IL 2. Although the enhanced phagocytosis with IFN-beta was consistently seen, little effect was detected with IFN-alpha and -gamma. Both methimazole and dexamethasone markedly inhibited phagocytosis. These results indicated that thyrocytes had phagocytic properties and that their phagocytic activity was modulated by cytokines, antithyroidal drugs and dexamethasone.

Phenotypic analyses and concanavalin-A-induced suppressor cell dysfunction of intrathyroidal lymphocytes from patients with Graves' disease

The expression of phenotypic markers and Concanavalin-A-induced suppressor activity was compared among mononuclear cells isolated from thyroid glands and peripheral blood of thionamide-treated patients with hyperthyroid Graves' disease and peripheral blood from normal subjects. Intrathyroidal lymphocytes were obtained by two different methods (TG-1 and TG-2 cells), gradient centrifugation of supernatants of minced thyroid tissue and overnight culture of thyroid debris after mechanical disaggregation and enzymatic digestion, respectively. The percentages of CD3+ cells (all mature T cells) among peripheral blood and TG-1 and TG-2 cells from Graves' patients were similar, but the percentages of B1+ cells (pan B cells) among the TG-1 and TG-2 cells were markedly increased compared to that in peripheral blood. The percentages of CD4+ cells among the TG-1 and TG-2 cells were significantly less than that in peripheral blood. The percentages of CD4+2H4+ cells among CD4+ cells in TG-1 and TG-2 cells also were significantly less than that in peripheral blood. The percentage of CD4+4B4+ cells among CD4+ cells in thyroid glands was markedly higher than that in peripheral blood. The percentages of CD8+ cells and CD8+CD11b- cells (cytotoxic T cells) in thyroid glands were significantly higher than those in peripheral blood from Graves' patients and peripheral blood from normal subjects. The CD8+CD11b+ cells were subdivided into two subpopulations on the basis of CD8 antigen density. The percentage of dull CD8+CD11b+ cells (natural killer cells) among TG-2 cells was lower than that in peripheral blood, but there was no significant difference in bright CD8+CD11b+ cells (suppressor-effector T cells) between thyroid glands and peripheral blood. The percent suppression induced by Concanavalin-A in both TG-1 and TG-2 cells was significantly decreased compared with that in peripheral blood. These results suggest that impairment of suppressor cell activity and an increased number of B cells exist in thyroid glands of patients with Graves' disease compared to those in peripheral blood. It, thus, appears likely that both B cell hyperactivity and suppressor T cell dysfunction may induce excess production of autoantibodies in the thyroid glands of such patients.

Synergy in antigen presentation by thyroid epithelial cells and monocytes from patients with Graves' disease

The present study was undertaken to examine the ability of thyrocytes from Graves' patients to present purified protein derivative (PPD) to autologous peripheral blood T cells. Normal human thyrocytes which were pre-cultured with interferon-gamma were able to induce the proliferation of T cells in response to PPD antigen, but unstimulated thyrocytes failed to do. Thyrocytes from Graves' patients on which HLA-DR antigens were expressed have an ability to induce the proliferation of T cells. Thyrocytes from Graves' patients which were pulsed with PPD antigen for 4 h were capable of stimulating proliferation of the T cells. However, the stimulation index of T cells co-cultured with thyrocytes and PPD were significantly lower than that of T cells co-cultured with monocytes and PPD. Sub-optimal numbers of monocytes which by themselves were unable to support T-cell proliferation synergistically augmented antigen presentation by thyrocytes. These results suggest that cellular interactions among thyrocytes, monocytes and T cells may perpetuate immune or autoimmune responses in thyroid tissues from Graves' patients.

Natural killer and natural killer-like cell activity of peripheral blood and intrathyroidal mononuclear cells from patients with Graves' disease

This study was undertaken to investigate the natural killer (NK) and natural killer-like (NK-like) cell cytotoxic activity toward autologous thyrocytes of peripheral blood mononuclear cells (PB-MNC) and thyroid gland mononuclear cells (TG-MNC) from previously hyperthyroid patients with Graves' disease, and the effects of recombinant interleukin-2 on such cytotoxic activity. The average cytotoxicities of PB-MNC from Graves' patients toward K562 cells (NK-sensitive cells), Raji cells (NK-resistant cells), and autologous thyrocytes were 23.9 +/- 10.8 (+/- SD) lytic units (LU), 7.4 +/- 3.8 LU, and 11.7 +/- 4.4 LU, respectively. There were no differences in the NK and NK-like cell activity of PB-MNC between Graves' disease patients and normal subjects. In contrast to PB-MNC from patients with Graves' disease, NK and NK-like cell activity was markedly decreased in TG-MNC (NK cell activity, 2.1 +/- 2.3 LU; NK-like cell activity, 1.5 +/- 1.5 LU). TG-MNC from Graves' patients had no cytotoxic activity against autologous thyrocytes. Using the monoclonal anti-Leu 7 and anti-CD16 antibodies and a two-color immunofluorescence method, the NK cell subsets were examined in PB-MNC and TG-MNC from Graves' patients. The percentage of CD16+ cells was significantly decreased in TG-MNC compared to PB-MNC, whereas there was no significant difference in the percentage of Leu 7+ cells between PB-MNC and TG-MNC. Incubation of TG-MNC with medium only did not increase the NK and NK-like cell activity of these cells. Furthermore, incubation of autologous PB-MNC with supernatants of minced thyroid tissues did not alter their NK and NK-like cell activity. The decreased NK and NK-like cell activity of TG-MNC was augmented when these cells were incubated with recombinant interleukin-2. These results suggest that the reduction of NK cell activity in TG-MNC may allow perpetuation of B-cell activation and lead to excessive production of autoantibody in thyroid tissue.

Magnetic resonance imaging in Pelizaeus-Merzbacher disease

Cranial computed tomography of a boy with clinical characteristics of the classic form of Pelizaeus-Merzbacher disease did not reveal a notable abnormality other than enlarged ventricles. Magnetic resonance imaging, however, demonstrated diffuse changes in the white matter with sparing of scattered small areas, suggesting persistent myelin islands which are a typical neuropathologic finding in Pelizaeus-Merzbacher disease. Magnetic resonance imaging appears more useful than computed tomography in confirming the diagnosis of Pelizaeus-Merzbacher disease.

In vitro cellular interactions among thyrocytes, T cells and monocytes from patients with Graves' disease

In order to investigate the cellular interactions among thyrocytes, T cells and monocytes in thyroid glands from patients with Graves' disease, we determined alterations of HLA-DR antigen expression on thyrocytes and T cells, and the production of interferon-gamma during coculture of thyrocytes, T cells and monocytes obtained from patients with Graves' disease. Thyroid glands were obtained at operation from 17 patients with Graves' disease. When thyrocytes and autologous peripheral blood T cells were cocultured for 7 days, the percentage of HLA-DR antigen expression on thyrocytes was significantly increased by T cells and that on T cells was also significantly increased by thyrocytes. Addition of autologous monocytes to the mixtures of thyrocytes and T cells significantly increased the expression of HLA-DR antigens on both thyrocytes and T cells compared with mixtures without monocytes. In culture supernatants, interferon-gamma was detected in 4 of 14 cocultures of thyrocytes and T cells, in 5 of 10 cocultures of thyrocytes, T cells and monocytes, but not in any cultures of thyrocytes alone, T cells alone and T cells and monocytes. Induction of HLA-DR antigen expression on thyrocytes and T cells was blocked by addition of anti-interferon-gamma monoclonal antibody to the mixture. These results suggest that HLA-DR antigen positive thyrocytes are able to induce the HLA-DR antigen expression of T cells in the presence of monocytes, and the activated T cells are capable of producing interferon-gamma which acts on thyrocytes to induce and maintain the expression of HLA-DR antigens.

Behavioral abnormalities and seizure susceptibility in rat after neonatal anoxia

Wistar rat pups were exposed to 99.99%-nitrogen gas for 10 minutes at 4 days of age, and then their behavior and susceptibility to pentylentetrazol (PTZ) induced seizure were investigated at the ages of 28 and 56 days. Neonatal anoxic rats exhibited hyperactivity in the open field examination and motor coordination disturbance in the inclined screen test, hyperirritability to the startle response and high susceptibility to PTZ at the age of 28 days. However, these behavioral changes and high susceptibility to PTZ were improved with development and there were no longer significant difference from controls rats at 56 days of age except the wire maneuver test. These results suggested that neonatal total anoxia could produce transient dysfunction of the developing brain, including increased susceptibility to seizure and behavioral abnormalities.

The remarkable proliferation of helper T cell subset in response to autologous thyrocytes and intrathyroidal T cells from patients with Graves' disease

We have studied cellular interactions among thyrocytes, intrathyroidal T cells and peripheral blood T cells from Graves' patients. In the autologous mixed lymphocyte reaction of Graves' patients, CD4+ cells were able to proliferate vigorously against autologous non-T cells, whereas CD8+ cells responded weakly to non-T cell stimulators. Furthermore, the proliferative response of the CD4+ 2H4+ suppressor-inducer T cell subset was increased like that of the CD4+ 2H4- helper T cell subset. In contrast to peripheral blood non-T cell stimulators, thyrocytes and intrathyroidal T cells had the ability to activate the CD4+ 2H4- helper T cell subset but were not able to cause proliferation both of CD4+ 2H4+ suppressor-inducer T cell and CD8+ suppressor/cytotoxic T cell subsets. The marked reduction in proliferative responses of CD4+ 2H4+ cells and CD8+ cells could not be attributed to a difference in kinetics or altered response to variable number of stimulator cells. On the basis of these findings, it is suggested that the concentration of the helper T cell subset may be progressively increased and suppressor circuits may be unable to be activated in thyroid tissues. These abnormalities in cellular interactions may induce the excessive production of autoantibodies.

Dysfunction of suppressor T cells in thyroid glands from patients with Graves' disease

To investigate the suppressor function of intrathyroidal (TG) T cells in Graves' disease, the percentage of suppressor T cell subsets and the suppressor function of TG and peripheral blood (PB) lymphocytes in Graves' disease were compared by determining the in vitro production of immunoglobulin G (IgG) in reconstituted mixtures of separated B, CD4+ (helper/suppressor-inducer T), and CD8+ (suppressor/cytotoxic T) cells. TG lymphocytes were obtained by gradient centrifugation of the supernatants of minced thyroid tissues. T Cells were separated by E-rosette formation, and CD4+ and CD8+ cell-rich populations were separated by a panning method using monoclonal anti-CD8 antibody. Mixtures of 5 X 10(4) B (PB1 or TG) cells, 2 X 10(4) CD4+ (PB or TG) cells, and 5 X 10(3) macrophages (PB or TG) were cultured with various numbers of CD8+ (PB) or CD8+ (TG) cells for 7 days with pokeweed mitogen, and IgG synthesis was determined by solid phase RIA. T cell subpopulations were quantitated by a direct immunofluorescence method using monoclonal anti-CD3, anti-CD4, and anti-CD8 antibodies. There was no difference in the percentages of CD8+ cells among total T cells between thyroid glands and peripheral blood from Graves' disease patients [mean PB, 39.8 +/- 9.8% (+/- SD); TG, 42.5 +/- 13.8%; n = 10]. IgG production by mixtures of B and CD4+ cells isolated from peripheral blood was not different from that by cells isolated from thyroid glands [mean PB, 1635 +/- 248 (+/- SE) ng/mL; TG, 1081 +/- 128 ng/mL; n = 19; P = NS]. The nonspecific suppressor activity of thyroid gland CD8+ cells was less than that of CD8+ (PB) cells [percent suppression of IgG production by mixtures of B (PB) and CD4+ (PB) cells, 12.5% vs. 57.0% (P less than 0.01); by mixtures of B (TG) and CD4+ (TG) cells, 5.8% vs. 38.9% (P less than 0.01)]. The suppressor-inducer function of CD4+ (TG) cells was also decreased compared with that of CD4+ (PB) cells. These results suggest that the impairment of suppressor cell activity may lead to excessive production of autoantibody in thyroid glands from patients with Graves' disease.

Reduction in the suppressor-inducer T cell subset and increase in the helper T cell subset in thyroid tissue from patients with Graves' disease

The expression of surface markers associated with activation and characterization was compared among T cells in thyroid glands and peripheral blood of 10 patients with Graves' hyperthyroidism receiving chronic antithyroid drug therapy, in peripheral blood of 15 patients with untreated hyperthyroid Graves' disease, and in peripheral blood of 21 normal subjects using two-color flow cytometry. In the chronically treated Graves' disease patients, the percentage of activated T cells (HLA-DR+ T cells) among total T cells was significantly higher in thyroid tissue than in peripheral blood, and the increase in percent activated T cells was also significant among both helper/inducer T cell (CD4+ cell) and suppressor/cytotoxic T cell (CD8+ cell) subsets. The percentage of activated T cells in peripheral blood was not significantly different between chronically treated hyperthyroid Graves' patients and normal subjects, whereas the percentage of activated T cells in the peripheral blood from untreated hyperthyroid Graves' disease patients was significantly higher than that in normal subjects or chronically treated hyperthyroid Graves' patients. The percentages of CD4+ cells and CD8+ cells among total T cells were not different between thyroid tissues and peripheral blood in patients with chronically treated hyperthyroid Graves' disease. When CD4+ were further divided into helper T cells (CD4+2H4- cells) and suppressor-inducer T cells (CD4+2H4+ cells) using two-color flow cytometry, the percentage of helper T cells among CD4+ cells was significantly higher in thyroid tissue than in peripheral blood, resulting in an increased ratio of CD4+2H4- cells to CD4+2H4+ cells. The percentage of CD4+2H4+ cells in peripheral blood, however, was not significantly different among untreated and chronically treated Graves' disease patients and normal subjects. From the findings of abnormalities in intrathyroidal T cell subsets, we suggest that the decrease in the function of suppressor T cells within the thyroids of Graves' disease patients may be due to a decrease in CD4+2H4+ cells within thyroid tissue.

Class II major histocompatibility complex antigen expression and cellular interactions in thyroid glands of Graves' disease

Class II major histocompatibility complex (MHC) antigens have been demonstrated on the surface of thyroid epithelial cells (thyrocytes) from patients with autoimmune thyroid disease. The present study was designed to investigate how the expression of class II MHC antigens is involved in autoimmune processes in Graves' disease by studying cellular interactions among thyrocytes, lymphocytes within thyroid glands (TG), and peripheral blood (PB) lymphocytes. Thyrocytes were prepared by collagenase digestion, and T or non-T cells were separated by E-rosette formation. Thyrocytes were cocultured in the presence or absence of interferon-gamma, and the expression of HLA-DR antigens on cultured thyrocytes was examined by an indirect immunofluorescence method using monoclonal anti-HLA-DR antibody and monoclonal anti-HLA-DQ antibody. The cellular interactions were assessed as the proliferative response of T cells to autologous stimulators, such as thyrocytes or lymphocytes. Expression of HLA-DR antigens on thyrocytes after culture for 18 h in the absence of interferon-gamma was found in two thirds of the patients with Graves' disease studied (n = 18). Interferon-gamma induced and maintained the expression of HLA-DR antigens on thyrocytes. The percentages of HLA-DR+T cells were significantly higher among TG-T cells than among PB-T cells [32.6 +/- 12.4% (+/- SD) vs. 12.2 +/-5.0%; n = 18; P less than 0.01]. Thyrocytes from Graves' patients induced proliferation of both autologous PB-T cells and TG-T cells, and TG-T cells stimulated proliferation of autologous PB-T cells. In conclusion, interferon-gamma induces HLA-DR antigen expression on thyrocytes from patients with Graves' disease, and these cells induce proliferation of autologous T cells, which may, in turn, act on thyrocytes to perpetuate the process.

Fatal neonatal nemaline myopathy: a case report

A fatal neonatal nemaline myopathy in a Japanese girl was described. The patient was hypotonic at birth and failed to establish effective respiration. Rod-like structures were observed within a variety of skeletal muscles, particularly in the diaphragm. This is the first case of fatal neonatal nemaline myopathy in which many satellite cells were observed.

Fatal neonatal nemaline myopathy

Nemaline myopathy was first reported in 1963 and has been considered to be a congenital, non-progressive myopathy with weakness since birth. However, severe forms leading to death in infancy have been rarely reported. Recently we necropsied a female infant with fatal neonatal nemaline myopathy who required mechanical ventilatory support immediately following delivery. She had suffered from recurrent pneumonia and died at five months of age. Light and electron microscopic studies on both muscle biopsy and autopsy specimens were diagnostic of nemaline myopathy. Characteristic rod-like structures were demonstrated within skeletal muscles, and accumulations of thin filaments were seen in numerous muscle fibers. The origin of these structures in the Z-disks and other morphologic features were the same as those of the rods occurring in congenital cases of rod myopathy. No involvement was observed in the cardiac muscle or in the smooth muscle of the gastrointestinal tract. It is likely that involvement of the skeletal muscles of the pharyngeal areas, intercostal spaces, and diaphragm might have contributed to the difficulty in swallowing and respiratory distress.