Therapeutic effect of novel anti-human Fas antibody HFE7a on graft-versus-host disease model.

In order to evaluate anti-human Fas antibody, we have established a new graft-versus-host disease (GVHD) model wherein splenocytes of human Fas transgenic mice (hFas-TgM) were transferred to immune-deficient SCID mice. In this model, although host SCID cells are not activated by or responsive to graft hFas-TgM cells, graft hFas-TgM cells are activated by and responsive to host SCID cells and thus cause GVHD symptoms. SCID mice that received hFas-TgM splenocytes had increased human Fas-positive lymphocytes in lymph nodes, decreased in body weight, and developed skin diseases, including rash and alopecia. Administration of novel anti-human Fas antibody HFE7A, which did not induce liver toxicity after administration to mice, decreased the level of the human Fas-positive lymphocytes, blocked the decrease of body weight, and suppressed development of skin diseases in this model. These results indicate that induction of apoptosis to activated graft cells with nontoxic anti-Fas antibody could reduce GVHD symptoms.

Calorimetric investigations of phase transitions of sonicated vesicles of dimyristoylphosphatidylcholine.

The process of conversion of large multilamellar vesicles (MLVs) of dimyristoylphosphatidylcholine (DMPC) into the final state of small unilamellar vesicles (SUVs) with an increase in time length of ultrasonic irradiation was investigated by calorimetry and negative-stain electron microscopy. The process was found out to be composed of two stages depending on the primary (near 24 degrees C) and secondary (near 19 degrees C) peaks due to the gel-to-liquid crystal phase (Tm) transition, respectively; a new transition peak for the secondary Tm appears after a maximum broadening of the primary Tm peak is attained. Sonicated vesicles characterized by the primary peak of the broadest shape were observed to be about 200 nm in mean diameter and mostly four or so lamellae, and have an internal aqueous space, in contrast to sonicated SUVs (approx. 40 nm in diameter) characterized by the limiting secondary Tm peak. Thermal data associated with the Tm transition for these two sonicated vesicles were compared with that of the MLV. The enthalpy and entropy changes and cooperative units increased in the order sonicated SUV < sonicated large vesicle < MLV. Furthermore, the enthalpy changes were revealed to fairly differ between the sonicated large vesicle and SUV. Based on the effect of the annealing treatment at -5 degrees C on these vesicles the present result suggested a large contribution of the aggregation state of DMPC molecules to the enthalpy possessed by the vesicles of a gel phase temperature, which is related to the mode of the Tm transitions, primary and secondary.

Decreased thyroidal triiodothyronine secretion in patients with anorexia nervosa: influence of weight recovery.

Basal thyroxin (T4), triiodothyronine (T3), and thyrotropin (TSH) concentrations were significantly lower before weight recovery in 10 patients with anorexia nervosa (AN) than they were in control subjects. After weight recovery, basal T4 and TSH levels were unchanged and significantly lower in AN patients than in control subjects. Basal T3 concentrations increased significantly after weight gain: however, concentrations remained lower than those in the control subjects. The maximum increase in T3 and T3 net secretory response to thyrotropin-releasing hormone (TRH), obtained before and after weight recovery, appeared significantly lower than that in control subjects: however, the increases in TSH responses were not different from those of control subjects. Thus, low T3 concentrations in AN patients may be due not only to impaired peripheral conversion of T4 to T3 associated with the altered nutritional state, but also to decreased thyroidal T3 secretion in response to endogenous TSH, which is indicative of hypothalamic-pituitary-thyroidal dysfunction.

Development of spontaneous hypothyroidism in patients with Graves' disease treated with antithyroidal drugs: clinical, immunological, and histological findings in 26 patients.

Graves' disease may result eventually in hypothyroidism in approximately 5-20% of patients. In a few such patients hypothyroidism was associated with TSH-blocking antibodies, but whether the frequency of TSH-blocking antibodies in such patients is as high as it is (21%) in patients with primary myxedema is not known. This study was undertaken to determine the presence of various immunoglobulins [TSH binding inhibitor immunoglobulins, thyroid-stimulating antibodies (TSAb), and TSH-blocking antibodies] in 26 patients with Graves' disease who developed hypothyroidism from 0.5-10 yr or more after discontinuation of antithyroid drug therapy. Eight of the 26 patients (31%) had TSH-blocking antibodies, 16 (61%) had TSAb, and 14 (54%) had thyroid hormone binding inhibitor immunoglobulins. Thyroid needle biopsies were performed in 9 patients. Three of 5 patients who had subclinical hypothyroidism had chronic lymphocytic thyroiditis, and all had positive TSAb titers. Three patients had the fibrous variant of chronic lymphocytic thyroiditis; their TSAb values were 902%, 431%, and 1290%. One patient had follicular hyperplasia. We conclude that TSH-blocking antibodies may account for hypothyroidism in approximately one third of patients with Graves' disease who were previously treated with antithyroid drugs, and that autoimmune thyroiditis is comparable for the hypothyroidism in the remaining two thirds of Graves' disease patients.

The significance of antithyroglobulin and antithyroidal microsomal antibodies in patients with hyperthyroidism due to Graves' disease treated with antithyroidal drugs.

The presence of serum antithyroglobulin (TGHA) and antithyroidal microsomal (MCHA) antibodies in Graves' disease patients is associated with lymphocytic infiltration of the thyroid. The aim of this study was to determine the clinical significance of TGHA and MCHA during and after treatment of hyperthyroidism due to Graves' disease. One hundred and seventeen such patients were treated for 2 yr with methimazole and then followed for an additional year or more (mean, 30 months). The patients were classified into the following three groups: group I, patients negative for TGHA and MCHA before and during the 2 yr of treatment; group II, patients positive for MCHA but negative for TGHA before and during the 2 yr of treatment; and group III, patients who were positive for both TGHA and MCHA before and during treatment. The relapse rates after discontinuation of treatment in these groups were 39% (13 of 33), 27% (13 of 48), and 11% (4 of 36), respectively; the value in group I was significantly higher than that in group III (P less than 0.01). The results suggest that the presence of TGHA and MCHA may influence the prognosis of Graves' disease in patients treated with methimazole. Those patients who had neither antibody before and during treatment were most likely to have a relapse of hyperthyroidism, and those who had both antibodies were least likely to have a relapse.

Methimazole-induced agranulocytosis in Japanese patients with Graves' disease.

We reviewed the records of approximately 7000 Japanese patients whose hyperthyroidism was treated with methimazole (MMI) alone. Four patients (Group I) developed agranulocytosis during a second course of MMI therapy and eight patients (Group II) during an initial course. Six patients (three in each group) received less than 30 mg MMI daily. Agranulocytosis occurred after more than 2 months of therapy (12 weeks-1 year) in five patients. Seven patients were less than 40 years of age. One patient displayed a gradual protracted development of agranulocytosis. These results indicate that agranulocytosis after MMI may occur irrespective of dose, age, duration of treatment, and with a second exposure.

Impaired glucagon secretion to insulin-induced hypoglycemia in anorexia nervosa.

In order to clarify the role played by pancreatic alpha-cell dysfunction in the impaired glucose recovery from hypoglycemia in patients with anorexia nervosa, the response of pancreatic alpha-cells to insulin-induced hypoglycemia was investigated in 16 patients with anorexia nervosa before and after treatment. The results were compared with those obtained after loading with arginine. Before treatment, despite comparable falls in plasma glucose levels, glucagon secretion was significantly reduced in the anorectic patients compared with control subjects. In addition, glucose recovery from hypoglycemia in the patients was attenuated. However, after treatment, both glucagon secretory activity and plasma glucose recovery following insulin-induced hypoglycemia were restored to normal. Plasma glucagon responses to arginine infusion were not significantly different in the untreated anorectic patients and control subjects. However, the plasma insulin response in the patients was significantly lower than in the control group. These results suggest that the impaired recovery of plasma glucose levels from insulin-induced hypoglycemia in patients with anorexia nervosa is primarily attributable to impaired pancreatic alpha-secretory capability. In addition, this abnormality in pancreatic alpha-cell function is reversible with treatment leading to improved nutrition and weight gain.

Angiotensin-converting enzyme and anorexia nervosa.

Angiotensin-converting enzyme (ACE) activity was measured in 10 patients with anorexia nervosa, 6 with hyperthyroid Graves' disease, and 7 with primary hypothyroidism. Patients with anorexia nervosa had a low serum ACE activity (9.8 +/- 2.2 IU/l), as compared to findings in normal subjects (13.4 +/- 3.5 IU/l) (P less than 0.05). Patients with hyperthyroid Graves' disease had high serum ACE activity (23.7 +/- 5.8 IU/l), as compared to levels in normal subjects (P less than 0.01), and patients with primary hypothyroidism tended to have low serum ACE activity (10.1 +/- 1.8 IU/l), compared to the normal subjects (P less than 0.1). Following weight gain (before; 71.3 +/- 10.2% of ideal body weight, after; 88.7 +/- 5.6% of ideal body weight), serum ACE activity in patients with anorexia nervosa reverted to within the normal range (13.8 +/- 3.5 IU/l), and serum T3 concentration was restored to the normal range (before; 0.7 +/- 0.2 ng/ml, after; 1.1 +/- 0.3 ng/ml). In these patients, ACE activity correlated with the per cent of ideal body weight (P less than 0.05). These data suggest that, in underweight subjects with anorexia nervosa, decreased serum ACE activities may relate to emaciation.

The dexamethasone suppression test for Japanese with eating disorders.

A one-mg oral overnight dexamethasone suppression test (DST) was conducted on 22 inpatients with eating disorders. To confirm that the dexamethasone tablets had been ingested, we measured the plasma concentrations of dexamethasone the next morning (at 0900 hr after DST). The diagnosis of anorexia nervosa and bulimia was made according to the criteria for DSM-III, respectively. Of the 22 patients with eating disorders, 16 satisfied the criteria for anorexia nervosa and 6 for bulimia. The DST was carried out within 2 weeks of hospitalization on each patient. The subjects were given 1 mg of dexamethasone in the evening (at 2300 hr) and blood samples were collected the following day (at 0900, 1600 and 2100 hr, respectively). The plasma cortisol and dexamethasone levels were concurrently determined by RIA. The criterion for non-suppression was a failure to suppress the plasma cortisol levels below 5.0 micrograms/dl in any one of the three samples. All but one patient with bulimia had ingested the dexamethasone. Thirteen (62%) of 21 patients with eating disorders were nonsuppressors. We found a significant positive correlation between the plasma cortisol levels at 1600 hr or 2100 hr and a decrease in ideal body weight (n = 16, r = 0.613, p less than 0.05; r = 0.75, p less than 0.01, respectively) and a significant inverse relationship between the plasma dexamethasone levels at 0900 hr and the plasma cortisol levels at 1600 hr was recognized (n = 21, r = 0.631, p less than 0.01). These results suggest that the blood dexamethasone levels as well as body weight might contribute to the abnormalities of DST seen in patients with eating disorders.

Thyroidal prelymphoma.

We treated a 32-year-old man with "thyroidal prelymphoma", morphologically resembling Hashimoto's thyroiditis and associated with monoclonal gammopathy (IgG, lambda). Immunohistochemistry revealed intracytoplasmatic monoclonal immunoglobulin (IgG, lambda) containing lymphoid cells in the interstitium of the thyroid tissue. After total thyroidectomy had been performed, the monoclonal immunoglobulin disappeared. Three years have passed since the surgery and this writing, there has been no recurrence. The existence of thyroidal prelymphoma suggests that chronic antigenic stimulation might produce lymphocytes which are more susceptible to neoplastic change (Hashimoto's thyroiditis----thyroidal prelymphoma----malignant lymphoma of the thyroid).