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This paper reports on a 22-yr old female patient with recurrent bouts of Henoch-Schönlein purpura since puberty occurring monthly at the time of menstruation. Remissions occurred during pregnancy, and on several occasions and in a dose responsive manner when the patient was prescribed birth control pills containing progesterone and oestradiol. Flares recurred when this therapy was discontinued. We hypothesize that this patient has an inflammatory disease involving neutrophil activation by excessive IgA, which is modulated by exogenous and endogenous sex steroids. It is unlikely that these hormonal influences are a common occurrence, but rather represent, in this case, a singular example of potential endocrine modulation of inflammatory disease.

To investigate whether the widely varying estimates of the prevalence of anti-Ku autoantibodies are explained by racial/ethnic differences.Consecutive African American or white patients who met the 1982 criteria for systemic lupus erythematosus (SLE) and who were evaluated over 10 years in North Carolina, Florida, and New York were tested by immunoprecipitation of K562 cell extract for anti-Ku as well as anti-nuclear RNP (nRNP)/Sm, anti-Ro/SSA, and anti-La/SSB autoantibodies.Anti-Ku autoantibodies were detected in sera from 18 of 155 African American patients with SLE (12%) versus 0 of 126 white patients (P0.0001, by Fisher's exact test). Anti-nRNP (63% versus 16%; P0.0001) and anti-Sm (23% versus 7%; P0.0004) autoantibodies were also more common in the African American subset. The 2 groups had comparable frequencies of anti-Ro/SSA and anti-La/SSB autoantibodies.Anti-Ku antibodies are common in African American patients with SLE but rare in whites, probably explaining the different estimates of their prevalence. In African Americans, the frequency is comparable with that of anti-La/SSB. Along with anti-Ku, anti-nRNP and anti-Sm autoantibodies are also overrepresented in African Americans, suggesting that a group of specificities is characteristically associated with SLE in African Americans.

To determine whether members of the highly phosphorylated SR protein family are autoantigens and, if so, to determine the frequency and molecular basis of antigen recognition.Native human SR proteins were purified to homogeneity from HeLa cells, and an enzyme-linked immunosorbent assay (ELISA) was developed. Further studies employed immunoblotting of both phosphorylated and dephosphorylated SR proteins.Anti-SR protein reactivity was frequently detected in the sera of patients with systemic lupus erythematosus (SLE). Sera from 52% of the SLE patients in a group of patients with a variety of autoimmune and other disorders (n = 137) and from 50% of the SLE patients in a separate group (n = 102) were positive in an ELISA. In contrast, sera from patients with other disorders, such as rheumatoid arthritis and primary antiphospholipid syndrome, reacted infrequently. Reactivity with double-stranded DNA (dsDNA), used in the diagnosis of SLE, did not correlate with SR protein reactivity. Anti-SR autoantisera did not bind highly charged unphosphorylated peptides related to the SR domain, which is rich in arginine and phosphoserine residues. Surprisingly, many of the epitopes were influenced by the presence or absence of SR protein phosphorylation. In immunoblots, some patient sera lost reactivity upon SR protein dephosphorylation, while others significantly gained reactivity.We have identified a novel set of autoantigens in SLE, the SR protein family of non-small nuclear RNP pre-messenger RNA splicing factors. Anti-SR autoantibodies are distinct from those which bind dsDNA. The identification of this new set of autoantigens and the observation that the auto-epitope(s) involves posttranslational modification offer new possibilities for understanding autoimmunity and its development.

Sex hormone binding globulin (SHBG) is a transport protein in human plasma which regulates the bioavailability of sex hormones, mediates membrane receptor signaling and may affect inflammatory processes, suggesting a regulatory role for this protein in the prevention of atherosclerosis. The current report summarizes literature implicating several members of the SHBG family in the regulation of hormonal and inflammatory processes which may be pertinent to the accelerated atherosclerosis seen in systemic lupus.

Treatment options for rheumatoid arthritis (RA) are expanding as research has provided a more complete understanding of the pathophysiology of the disease. Three disease-modifying agents approved in the last 18 months for early intervention in RA are etanercept, leflunomide, and infliximab. For the relief of the signs and symptoms of RA, the new selective cyclooxygenase-2 (COX-2) inhibitors are joining the available nonsteroidal anti-inflammatory drugs. One COX-2 inhibitor is approved for use in RA, and another is under investigation for that indication. As a class, the COX-2 inhibitors offer efficacy similar to traditional NSAIDs but with less GI and platelet toxicity.

There is no greater contribution that our understanding of the antiphospholipid syndrome (APS; Hughes syndrome) might give us than the etiopathogenesis of atherosclerosis, the most common cause of death in the world. Although the etiology remains unknown, It is a multifactorial disease. What we do know is that it is dependent on a number of variables. Some factors known to be associated with the progression of atherosclerosis include hypercholesterolemia and modified lipids, high homocysteine levels [1], hypertension, and infection. Perhaps the latter might seem surprising, but there is solid evidence that infection — suspected for many years — might be at the heart of atherosclerosis [2].

To determine the frequencies at which either a valine or leucine occurs at position 247 in the beta2-glycoprotein I (beta2GPI) gene of normal individuals of the Caucasian, African American, and Asian ethnic groups and to compare these data with those in patients with the antiphospholipid syndrome (APS), with and without anti-beta2GPI antibodies.The DNA segment containing the position-247 polymorphism was amplified by seminested polymerase chain reaction, and the polymorphism was detected by restriction endonuclease digestion. DNA samples from 370 healthy controls of different racial backgrounds were analyzed, and the results were compared with those from 149 APS patients (66 primary; 83 secondary). Allele and genotype frequencies were compared using Fisher's exact test. When significant differences were detected, pairwise comparisons were made using Fisher's exact test with a Bonferroni adjustment.Allele and genotype expression was significantly different (P0.0001 for both) among the 3 races, with the V allele and the VV genotype occurring most often among Caucasians, less among African Americans, and least among Asians. Conversely, the V allele and the VV genotype were found more frequently among Asian APS patients than among controls (P = 0.0028 and P = 0.0023, respectively). No significant differences in allele or genotype frequencies were seen in comparisons of the Caucasian or the African American patients with appropriate controls. The differences in allele and genotype frequencies seen in the Asian APS patients were restricted to the anti-beta2GPI-positive patients (P = 0.0018 and P = 0.0005, respectively).In Asian patients with APS, expression of a V at position 247, especially in the homozygous state, is significantly associated with the presence of anti-beta2GPI antibodies and, therefore, can be viewed as a major risk factor in this ethnic group (odds ratio 9.19 and 16.33, respectively).

Thrombosis in the antiphospholipid syndrome has been associated with acquired deficiency of the anticoagulant protein S. We sought evidence that beta2-glycoprotein I, a major target antigen for antiphospholipid antibodies, is involved in regulation of protein S activity. Incubation of purified protein S or plasma with beta2-glycoprotein I reversed functional modulation of protein S by its plasma inhibitor, the C4b-binding protein. In a plasma-free ELISA, beta2-glycoprotein I prevented the binding of protein S and C4b-binding protein when preincubated with immobilized protein S but not when similarly preincubated with C4b-binding protein. beta2-glycoprotein I in fluid phase interfered with precipitation of protein S by sepharose-bound C4b-binding protein. Effects of beta2-glycoprotein I on protein S function were inhibited by one of four monoclonal anti-beta2-glycoprotein 1 antibodies. These data suggest that beta2-glycoprotein I helps maintain adequate plasma levels of circulating free, active protein S. Antiphospholipid (anti-beta2-glycoprotein I) antibodies might cause sporadic thrombosis, at least in part, by impairing this novel regulatory mechanism.

To determine the performance characteristics of enzyme-based immunoassay (EIA) kits for the detection of antinuclear and other autoantibodies of defined specificities.Nine manufacturers of EIA kits to detect antibodies of defined specificities participated in a study in which they received coded sera from the Centers for Disease Control and Prevention. These coded sera contained different dilutions of antibody of one specificity mixed with sera containing antibodies of other specificities. The manufacturers were asked to use their standard technology to determine antibody content and send the data to a committee of the International Union of Immunological Societies for analysis. The data were analyzed for sensitivity and specificity in the detection of anti-double-stranded DNA (anti-dsDNA), anti-single-stranded DNA, antihistone, anti-Sm, anti-U1 RNP, anti-SSA/Ro, anti-SSB/La, anti-Scl-70 (DNA topoisomerase I), anticentromere, and anti-Jo-1 antibodies. In addition, replicate samples were included in the coded sera to evaluate the precision of each EIA method.Lack of sensitivity and specificity was most evident in the anti-dsDNA and anti-Sm kits, although 2 kits for anti-dsDNA achieved acceptable sensitivity and specificity. Generally, anti-SSA/Ro, anti-SSB/La, anti-Scl-70, anticentromere, and anti-Jo-1 kits performed well. Many false-positive results were obtained with a multiple myeloma serum containing cryoprecipitates, but multiple myeloma sera without cryoprecipitates presented no problem in the EIA system. Precision, based on evaluation of replicate samples, varied from very good to poor.No single manufacturer was clearly superior to others in terms of their products' overall sensitivity, specificity, and precision. Areas that needed improvement were in kits for the detection of antibodies to dsDNA and to Sm antigen. Some EIA kits achieved good sensitivity and specificity. Individual manufacturers were informed of the performance of their respective kits so they could take measures to correct perceived deficiencies and thus improve the reliability of a group of important diagnostic assays used in the evaluation of systemic rheumatic diseases.

Surprisingly, the autoimmune diseases predominate in women of childbearing years. Recent evidence suggests that these diseases are the result of some interaction of the hypothalamic-gonadal axis with the immune system. The median age for rheumatoid arthritis is 45 years, the median age for lupus erythematosus is 25. Other illnesses, which are autoimmune in character, such as Sjögren syndrome, scleroderma and the vasculitides, are also more commonly found in women. There is no link that ties these illnesses together, except for gender and various disparate immune manifestations such as autoantibodies. The etiopathogenesis of these diseases is reviewed. These diseases are notoriously difficult to diagnose; they mimic other illnesses in their early presentations. Accompanying illnesses such as migraine headaches, Hashimoto's thyroiditis, and fibromyalgia are discussed as related entities. Immunosuppression of diseases like rheumatoid arthritis and lupus erythematosus, is discussed. Various methods of management are considered, such as the use of steroids, cytotoxic agents, and new experimental agents, such as DHEA and IVIG.

To determine whether antiphospholipid antibodies (aPL) are more prevalent in cardiac patients taking procainamide than in a control population of similar elderly cardiac patients and to determine whether these antibodies react in an ELISA in which the primary antigen is beta 2-glycoprotein I (beta 2-GPI).aPL and antibodies to beta 2-GPI were measured in 66 patients taking procainamide from a Veterans Administration Medical Center population and a control group of 30 similar cardiac patients not taking procainamide.21% of the patients taking procainamide and no control patients were found to have moderate to high aPL. There were similar results in an assay that measured anti-beta 2-GPI in the absence of exogenous phospholipids. aPL were associated with antinuclear antibodies and antihistone antibodies but not with diabetes or clinical manifestations of drug related lupus. There was no increase in cholesterol or past thrombotic history associated with aPL, but there was a frequent history of noncardiac thrombosis in patients taking procainamide (25.7%).The predictive significance of procainamide induced aPL remains unknown but beta 2-GPI dependent aPL may be of some concern in this elderly population already at high risk for thrombosis.

There are many factors that predispose women to autoimmune disease. The protective effect of testosterone during development prevents most males from getting autoimmune disease, although in some instances this protective effect can be bypassed by either genetic anomalies or endocrinopathies. Autoimmunity is defined as the development of symptoms and antibodies referable to one or another autoimmune disease. Some of the factors that predispose young women to autoimmunity also directly involve the endocrine system and indirectly, disorders of gonadal development. Altered sex steroid metabolism is one endogenous factor that predisposes a young woman to autoimmunity. The metabolism of estrone which can be directed to either the 16-or the 2-metabolites by diet, thyroid function, or certain drugs has a major influence on immune function and possibly gonadal pathology. Attempts to shift the metabolism of estrone to the 2-compounds with a variety of agents actually decreases the predisposition to autoimmunity. Other pre-disposing factors are all related to hormone metabolism and include hyperprolactinemia, the use of exogenous estrogenic agents, or compounds that change basic steroid metabolism. Most of these conditions are reversible.

The autoimmune diseases are more common in women than men. The actual prevalence ranges from the high of 10 to 15 females for each male for systemic lupus erythematosus to four females for every male with rheumatoid arthritis. Though these diseases are found in the very young and the aged, the high prevalence is observed after puberty in most patients. These diseases vary with regard to severity, and most investigators suspect that the signs and symptoms of these diseases vary with menstrual cycle and change severity during pregnancy. The collagen diseases are devastating to the health of young women. Rheumatoid arthritis occurring at a mean age of 40 years results in debilitating erosive changes in bone with morning stiffness and eventual crippling. Systemic lupus erythematosus, Sjögren's syndrome and others, common to women of the childbearing years, act in several ways to destroy organ systems of the body. Virtually any organ system of the female anatomy can be affected by these illnesses. In the case of lupus, the disease has protean manifestations, such as procoagulation, renal destruction, skin disease, unrelenting arthropathy and arthritis, and encephalopathy (to name only a few). The underlying mechanisms are not known; however, the immune system acts to destroy tissue via immune complex deposition and through the action of cytotoxic lymphocyte activity. There is an association of both clinical signs and autoantibody subpopulations with markers of the HLA-D or MHC II locus on chromosome 6. No constitutive gene for any of the collagen vascular diseases has been identified in the human. Evidence exists to support an altered metabolism of estrogens and androgens in patients with these diseases. Recent data also indicate that increased estrogen levels might initiate autoimmune diseases in many women and men. Estrogen hydroxylation is increased in both men and women with autoimmune diseases like lupus. The mechanisms are unknown, although estrogenic metabolites have been shown to increase B cell differentiation and activate T cells. Moreover, isolated cases of hyperprolactinemia have been observed in association with these hyperestrogenic states, and treatment of hyperprolactinemia has been shown to ameliorate diseases like lupus. Androgen oxidation is also increased in patients with autoimmune disease, but this abnormality has been observed only in patients with lupus, and only women at that. The result is that women with autoimmune diseases like lupus and rheumatoid arthritis have lower plasma androgens than control cases. These data have supported the use of weak androgens, e.g., DHEA, for the treatment of lupus.

Many of the diseases of the immune system, particularly the rheumatic diseases, predominate in women. Various reasons for these differences are proposed. Included in this paper are the differences between men and women's immune system and the sex hormone and gonadotrophin effects on immunity. The hydroxylation of estrogen is discussed in the context of lupus erythematosus, and various hormones such as progesterone and the androgens are compared with regard to their effects in the normal host and the woman with disease.

Steroid induced psychosis in SLE is rare but clinically important, and often difficult to distinguish from lupus cerebritis. We report a patient with SLE who became depressed following an increase in her steroid dosage. Based on her clinical presentation and high levels of antibodies to P ribosomal proteins (both in CSF and serum) a diagnosis of lupus cerebritis was made. Steroid dosage, time intervals, and the duration of mental changes may help in differentiating steroid psychosis from lupus cerebritis. No single laboratory test sufficient to establish a definitive diagnosis of lupus cerebritis is available at the present time. However, elevated levels of antibodies to P ribosomal proteins may assist in confirming the diagnosis of this condition.

Studies in adults with systemic lupus erythematosus (SLE) have shown normal estrogen and lowered androgen levels in serum and abnormal metabolism of estrogen. In our prospective study we tested the hypothesis that one or more of the following factors account for the increased incidence of SLE and pauciarticular juvenile rheumatoid arthritis (JRA) in females: (a) increased estrogen; (b) decreased androgen and (c) increased estrogen receptor in the peripheral blood mononuclear cells (PBMC). Serum and PBMC were collected from 51 healthy children (36 M: 20 F), 17 with JRA (all female) and 37 with SLE (11 M: 26 F). Estrogen receptor was measured in cytosol from PBMC using monoclonal antibody to estrogen receptor and solid phase enzyme immune assay. Serum levels of estrogen, androgen, prolactin, follicle stimulating hormone (FSH) and luteinizing hormone (LH) were measured using standard radioimmunoassay. There were no significant differences in serum levels of estrogen and prolactin between healthy children and patients. Free androgen was lower in postpubertal boys and girls with SLE compared to healthy children. FSH and LH levels were higher in postpubertal boys and girls with SLE compared to healthy individuals. This trend, while not reaching statistical significance, was supported by a higher percentage of female patients with SLE and abnormal serum levels of FSH (p = 0.001), LH (p = 0.004) and prolactin (p = 0.001). The results of these preliminary studies suggest that the role of prolactin, FSH and LH in rheumatic diseases deserves further study.

Three men and 4 women with systemic lupus erythematosus (SLE) received 100 mg of 19-nortestosterone decanoate in weekly intramuscular injections over a period of 3 to 24 months. During therapy in the men plasma luteotrophic hormone and free testosterone levels decreased while estrogen levels increased. Anti-DNA antibodies also increased for unknown reasons. Serological changes in two men coincided with an overall increase in the clinical activity of SLE and the appearance of new onset Raynaud's phenomenon and pleuropericardial disease. In contrast, women treated with 19-nortestosterone showed clinical stability despite the persistence of high titer antibodies to DNA, and were able to continue therapy for as long as 16 months in one case. These data indicate that men and women with SLE respond differently to synthetic androgen therapy. Additionally, dissociation of clinical signs and symptoms from serological variables seems possible.

Ribonucleoprotein particles containing Sm antigen were separated from particles containing both Sm and RNP antigens by ion-exchange chromatography to study the recognition of these antigens by autoimmune sera. By using the separated antigens, anti-Sm and/or anti-RNP antibodies were detected in approximately 60% of sera from systemic lupus erythematosus patients by both enzyme-linked immunosorbent assay and immunoprecipitation of radiolabeled antigens followed by analysis on sodium dodecyl sulfate-polyacrylamide gels. These antibodies were detected in 30% of the same sera using the standard passive hemagglutination technique. Competition experiments demonstrated that all of the sera tested that contained anti-Sm antibodies also had anti-RNP-like reactivity. This latter reactivity usually represented 80% or more of the total Sm and RNP binding activity in lupus sera. The binding to RNP-like determinants by several of the sera was uniquely resistant to treatment of the antigen with snake venom exonuclease. These studies indicate that humoral immunity against Sm and RNP antigens in systemic lupus erythematosus is directed primarily against a single type of ribonucleoprotein particle in which the two antigens are physically associated. The specific binding to a single type of ribonucleoprotein particle suggests that this particle may be especially immunogenic and that it might play an important role in induction of the humoral immune response to Sm and RNP.

The immune response was assessed in 13 competitive bodybuilders self-administering anabolic-androgenic steroids and ten competitive bodybuilders not administering these drugs. Laboratory assessment included the number and relative distribution of T-cells, T-helper/inducer cells, T-cytotoxic/suppressor cells, activated T-cells, lymphocyte transformation to the mitogens, pokeweed mitogen (PWM), phytohemagglutinin (PHA), Concanavalin-A (CON-A), Staphylococcus aureus Cowan strain I (SAC), serum immunoglobulins, and natural killer (NK) activity. There were no significant differences in T-cell subsets among steroid users and non-users, but lymphocyte transformation studies revealed that the anabolic-androgenic steroid-using group had enhanced proliferative ability to the B-cell mitogen, SAC, in comparison to non-bodybuilding controls. NK activity was significantly (P less than 0.05) augmented in the anabolic-androgenic steroid users but not in the non-using bodybuilders. Serum immunoglobulin levels, in particular IgA, were significantly (P less than 0.017) lower in the steroid-using group. Four of 13 steroid users and three of eight non-steroid-using bodybuilders had detectable antinuclear antibodies. These studies indicate that 1) anabolic-androgenic steroid use as practiced by contemporary athletes is a potent modulator of immune responsiveness and 2) autoantibodies are prevalent in strength-trained men even in the absence of anabolic steroid use.

Levels of anti-Ku (p70/p80) antibodies were measured longitudinally in sera from four individuals with systemic lupus erythematosus or related disorders. Antibodies to the native Ku antigen (p70/p80 complex) varied over a range of up to 577-fold. Large fluctuations were also observed in the levels of autoantibodies to several distinct epitopes of the Ku (p70/p80) antigen. Levels of these individual autoantibody populations generally paralleled one another, suggesting that they are coordinately regulated. A similar pattern of anti-DNA antibody fluctuation was seen in some sera. To examine the possibility that these autoantibodies were generated by polyclonal B cell activation, the levels of anti-Ku (p70/p80) and anti-DNA antibodies were compared to the levels of antibodies to Escherichia coli proteins, tetanus toxoid, and bovine insulin, transferrin, cytochrome c, serum albumin, and thyroglobulin. In sera from the same individual, anti-Ku (p70/p80) antibodies were sometimes produced in the complete absence of polyclonal activation, and at other times were accompanied by increased polyclonal activation. Anti-DNA antibody levels more closely paralleled the level of polyclonal activation than did the anti-Ku (p70/p80) levels. These studies suggest that anti-Ku (p70/p80) antibodies are generated by an antigen-selective mechanism, but that polyclonal activation frequently, although not invariably, accompanies autoantibody production. This observation is consistent with the possibility that polyclonal activation might be secondary to autoantibody production.

Estrone hydroxylation, testosterone oxidation and the products of such hormone metabolism were studied in hypogonadal males. The sex steroid metabolism of patients with Klinefelter's syndrome with systemic lupus erythematosus (SLE) is similar to that of women with SLE.

Humans with SLE were studied with regard to their ability to metabolize estradiol and testosterone. Significant abnormalities in the patterns of metabolism of both classes of sex steroids were found. Estradiol hydroxylation at C-16 was more extensive in both males and females with SLE -- leading to more estrogenic metabolites; and testosterone oxidation was elevated in patients with SLE resulting in a decrease in total androgens. Some normal first degree relatives of patients with SLE also had abnormalities of estradiol hydroxylation.

Sex hormones have been implicated in the pathogenesis of many autoimmune disorders, presumably through regulatory influences on the immune system. However, the mechanisms of sex steroid action on humoral and cellular immune responses are not precisely understood. In this study, the in vitro effects of physiologic concentrations of 17 beta-estradiol and testosterone on the Ag non-specific differentiation of human PBMC were examined using optimal and sub-optimal doses, respectively, of PWM. In cultures of PBMC from 14 normal donors (7 men and 7 women, aged 25 to 45 yr), 17 beta-estradiol (0.5 to 30 ng/ml) enhanced PWM-induced generation of PFC by 46% (p less than 0.01), whereas testosterone (10 to 300 ng/ml) inhibited PFC generation by a mean of 36% (p less than 0.001). The enhancing and suppressing effects of the sex steroids on PBMC occurred early inasmuch as estradiol and testosterone had to be added to the cultures at their initiation (6 and 24 h, respectively) in order to observe their influence. Moreover, deletion of the hormones from the cultures after as short a period as 12 h did not obviate their effects. There was no alteration of the kinetics of the response to PWM or an effect on the number of spontaneous PFC generated in vitro in the absence of PWM. In addition, there was no difference among men and women in response to either sex steroid, and within the female group, no variation was observed on different days of the menstrual cycle. These studies demonstrate direct immunoregulatory effects of specific sex steroids on human PBMC and support the idea that these hormones may have a role in the pathogenesis and treatment of some autoimmune disorders.

An immune-mediated disease was produced in 9 of 17 (53%) normal healthy cats by daily p.o. administration of 150 mg of 6-propylthiouracil (PTU). This disease syndrome is characterized by lethargy, weight loss, lymphadenopathy, hemolytic anemia, a positive direct antiglobulin test (DAT) and antinuclear antibodies (ANA). The duration of drug administration before the development of a positive DAT and/or ANA ranged from 3 to 8 weeks (Mean +/- S.E.M. = 4.5 +/- 0.6), whereas the duration before the onset of clinical signs ranged from 4 to 8 weeks (6.1 +/- 0.6 weeks). On cessation of PTU administration, clinical signs resolved in all cats within 2 weeks, and the DAT and test for ANA were negative within 1 to 4 weeks (1.9 +/- 0.4 weeks). During nine PTU-rechallenge periods in four cats, both the mean time to develop a positive DAT and ANA (2.5 +/- 0.8 weeks) and the mean time to develop overt clinical signs (2.6 +/- 0.7 weeks) were shorter than similar mean times in the initial PTU treatment period (P less than .01). During nine episodes of PTU-induced disease in seven cats, PTU administration was discontinued and replaced with 150 mg of 6-propyluracil (PU), a nonsulfur analog of PTU. Resolution of both clinical and serologic signs of disease occurred in seven of the nine disease episodes within 1 to 3 weeks (2.1 +/- 0.4 weeks). In the two cats whose disease did not resolve on PU, one was sacrificed after 1 week of PU administration, without clinical or serologic resolution, because of the severity of the PTU-induced disease.(ABSTRACT TRUNCATED AT 250 WORDS)