Decrease of interleukin 6 during the first 12 months is a prognostic marker for clinical outcome during 36 months treatment with disease-modifying anti-rheumatic drugs

The aim of this study was to determine prognostic markers for the outcome after 36 months of therapy with disease-modifying anti-rheumatic drugs (DMARDs) in patients with rheumatoid arthritis (RA) and to study serial cytokine serum levels. During 36 months, 20 patients receiving DMARDs (nine patients gold sodium thiomalate and 11 patients methotrexate, no comparison undertaken) were followed for clinical and laboratory data. Investigation at baseline, 12, 24 and 36 months, included clinical, radiological and laboratory parameters such as erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), and interleukin (IL)-1 beta, IL-6, tumor necrosis factor alpha (TNF-alpha), IL-1 receptor antagonist (IL-1RA) and IL-2. During the 3 yr of therapy, the patients showed significant clinical improvement and decline of ESR, CRP, and serum levels of IL-6 and IL-2. The decrease in IL-6 serum levels during the first year of therapy correlated significantly with the decrease, after 36 months, in the number of inflamed joints (r = 0.7608, P < 0.005), Lansbury index (r = 0.6642, P < 0.005) and morning stiffness (r = -0.6561, P < 0.005). In contrast to IL-6 or IL-2, TNF-alpha and IL-1RA did not vary significantly during the 3 yr of therapy. During 36 months of therapy, patients treated with DMARD showed significant improvement of clinical parameters and a trend for delayed progression of radiographic damage. The decrease in IL-6 concentration in serum during the first 12 months was the best prognostic marker for the clinical outcome after 36 months of DMARD therapy.

Elevated anticardiolipin antibodies in autoimmune haemolytic anaemia irrespective of underlying systemic lupus erythematosus

In patients with systemic lupus erythematosus (SLE) and concomitant Coombs positive autoimmune haemolytic anaemia (AIHA) anticardiolipin antibodies (aCL) are found more frequently and at higher titres than in SLE patients without AIHA. In order to assess if aCL elevation is primarily associated with the underlying SLE, or with AIHA itself, we examined AIHA patients with and without underlying SLE for the presence of aCL. aCL (IgG and IgM) were determined by ELISA in 74 SLE patients without AIHA, 22 SLE patients with AIHA, 50 patients with idiopathic AIHA (warm-reactive autoantibodies), 52 patients with idiopathic AIHA (cold-reactive autoantibodies) and 50 healthy controls. The mean IgG and IgM aCL titres in SLE patients without AIHA (IgG 37.0 U/ml, IgM 8.9 U/ml) were significantly elevated compared with the values in healthy controls (IgG 9.1 U/ml, IgM 3.2 U/ml; P < 0.005). The mean aCL levels in SLE patients with AIHA (IgG 53.2 U/ml, IgM 28.2 U/ml) were higher than in SLE patients without AIHA (P = 0.09 for IgG, P < 0.005 for IgM). Interestingly, the mean aCL levels of patients with idiopathic AIHA (warm-reactive autoantibody type: IgG 29.2 U/ml, IgM 19.3 U/ml; cold-reactive autoantibody type: IgG 27.4 U/ml, IgM 18.9 U/ml) were also significantly elevated compared with healthy controls P < 0.001). As aCL are elevated not only in SLE (with and without concomitant AIHA) but also in idiopathic AIHA it can be speculated that aCL are involved in the pathomechanism of autoantibody-induced erythrocyte destruction per se irrespective of an underlying SLE.

[Cardiovascular and pupillary autonomic and somatosensory neuropathy in chronic diseases with autoimmune phenomena. A comparative study of patients with Crohn disease, ulcerative colitis, systemic lupus erythematosus, progressive systemic sclerosis and type I diabetes mellitus]

BACKGROUND

During the last years, examination of autonomic nervous function and of autonomic neuropathy has attracted attention not only in diabetes mellitus research but also in other areas of internal medicine. However, patients with various chronic diseases with autoimmune phenomenons have never been investigated in a comparative study with standardized examination techniques. Hence, the aim of the study was to examine the prevalence and the severity of autonomic neuropathy in patients with the following chronic diseases.

PATIENTS AND METHODS

We investigated 28 patients with Crohn's disease (CD: age: 32.4 +/- 2.0 y), 17 patients with ulcerative colitis (UC: 39.7 +/- 3.6 y), 39 patients with systemic lupus erythematosus (SLE: 34.9 +/- 2.0 y), 38 patients with progressive systemic sclerosis (pSS; 51.5 +/- 2.4 y) and 65 patients with insulin-dependent diabetes mellitus (IDDM: 35.5 +/- 1.6 y). Cardiovascular autonomic (cANP), pupillary autonomic (pANP), and sensorimotor (ssNP) neuropathy were assessed by standardized techniques.

RESULTS

Prevalence rates for cANP, pANP and ssNP were found to be 0%, 19%, and 7% in CD, 6%, 25%, and 18% in UC, 5%, 29%, and 10% in SLE, 11%, 16%, and 32% in pSS, and 26%, 66%, and 29% in IDDM, respectively.

CONCLUSION

The study demonstrated patients with IDDM to have the highest prevalence rates of cANP and pANP. Patients with other chronic diseases, particularly SLE, pSS and UC, had high prevalence rates of pANP. This may be due to alterations of structures of the central nervous system in these patients. cANP was rare in patients with inflammatory bowel disease and ssNP was found very often in patients with pSS, probably due to local fibrotic lesions. The various disease groups differ in the pattern and severity of autonomic and sensorimotor neuropathy, which indicates that different structures and neuropathogenic mechanisms may be involved.

Anorectal function in systemic sclerosis: correlation with esophageal dysfunction?

PURPOSE

This study was designed to compare esophageal and anorectal function parameters in patients with systemic sclerosis and to define the role of anorectal manometry in the diagnosis of gastrointestinal involvement of systemic sclerosis.

PATIENTS AND METHODS

Twenty-six consecutive patients (22 females) with systemic sclerosis originally referred for assessment of esophageal function were evaluated by esophageal and anorectal manometry. Anorectal function parameters were compared between patients with normal and those with disturbed esophageal function.

RESULTS

A total of 17 of 26 patients (65 percent) had severe esophageal dysfunction with aperistalsis of the lower two-thirds of the esophagus, whereas 9 patients (35 percent) had normal esophageal manometry. Only three patients (11.5 percent) suffered from occasional fecal incontinence. Anorectal function parameters (resting pressure, maximum squeeze pressure, perception threshold) were not significantly different between patients with normal and those with disturbed esophageal motility. Rectoanal inhibitory reflex was excitable in nearly 90 percent of patients.

CONCLUSION

In an unselected group of patients with systemic sclerosis, fecal incontinence and abnormal anorectal function are rather rare findings. Anorectal manometry cannot differentiate between patients with and without gastrointestinal involvement of systemic sclerosis.

An overview of the treatment of childhood SLE

Current recommendations for the treatment of pediatric SLE are from uncontrolled trials, case reports, retrospective descriptive data or extrapolation from studies in adults. Glucocorticoids are the mainstay of therapy and the doses depend on the disease severity. Diffuse proliferative glomerulonephritis (DPGN) requires high-dose prednisone for prolonged periods of time. We suggest the addition of azathioprine for DPGN at the time of diagnosis of DPGN and reserve cyclophosphamide for refractory cases. While we do not recommend the routine use of cyclophosphamide in this or other forms of lupus nephritis, others advocate the aggressive use of intravenous cyclophosphamide and prednisone. Severe central nervous system disease should be treated with high dose prednisone and immunosuppressive agents are reserved for life-threatening disease or steroid failure or dependency. We suggest the routine use of hydroxychloroquine in all cases of SLE at a dose of 5 mg/kg/day (maximum of 400 mg/day). Methotrexate has been recently used with some success in both children and adults, the safety profile appears to be very good and therefore further studies of this drug are warranted. Collaboration in the development of a limited number of defined treatment protocols and large scale collection of data on a multicenter and multinational basis is needed if we hope to improve the outcome of patients with severe disease.

Small-cell lung cancer, paraneoplastic cerebellar degeneration and the Lambert-Eaton myasthenic syndrome

Several cancers, especially lung, ovarian and breast, can cause paraneoplastic cerebellar degeneration. The presence of different antineuronal antibodies associated with different cancers and paraneoplastic cerebellar degeneration suggests that several immunological mechanisms may result in the same neurological disorder. In patients with small-cell lung cancer, paraneoplastic cerebellar degeneration may occur with or without Hu antineuronal antibodies (HuAb), indicating that patients with the same tumour can develop paraneoplastic cerebellar degeneration by different immunological mechanisms. Furthermore, paraneoplastic cerebellar degeneration sometimes occurs in association with the Lambert-Eaton myasthenic syndrome. In order to try to understand the clinical implication of antineuronal antibodies in patients with small-cell lung cancer, we examined the serum of 57 patients with presenting symptoms of paraneoplastic cerebellar degeneration for the presence of HuAb and P/Q- and N-type voltage-gated calcium channel antibodies. Patients with paraneoplastic cerebellar degeneration who were HuAb positive were compared with HuAb negative patients with respect to neurological symptoms, course of the neurological disorder, response to treatment, tumour prognosis, pathological findings, and cause of death. The tumour outcome and serological findings of these patients were also compared with those of 109 small-cell lung cancer patients without paraneoplastic syndromes of the CNS. Titres of HuAb were classified as 'high' (immunoblot titre > 1:10,000) or 'low' (< 1:10,000), the latter similar to the antibody titres detected in some small-cell lung cancer patients without paraneoplastic symptoms. Twenty-five patients with paraneoplastic cerebellar degeneration (44%) had high titres of HuAb, four (7%) had low titres of HuAb, and 28 (49%) were HuAb negative; for clinical comparisons with the patients with high titres of HuAb, the four patients with low antibody titres were included in the HuAb negative cohort. None of the 109 small-cell lung cancer patients without paraneoplastic symptoms had high titres of HuAb. The presence of high titres of HuAb defined a subset of patients who differed from the HuAb negative paraneoplastic cerebellar degeneration cohort, HuAb positive patients were more likely to be female (P < 0.01), to have multifocal neurological disease (brainstem encephalopathy and sensory neuropathy being common extracerebellar manifestations) (P < 0.002), and be severely disabled (P < 0.005). A total of nine patients (16%) from both paraneoplastic cerebellar degeneration groups developed electrophysiologically confirmed Lambert-Eaton myasthenic syndrome. Seven of these nine patients had serum available for P/Q-type voltage-gated calcium channel antibody testing and all seven were positive. In addition, 20% of HuAb negative paraneoplastic cerebellar degeneration patients without clinically identified Lambert-Eaton myasthenic syndrome had P/Q-type voltage-gated calcium channel antibodies, while only 2% of small-cell lung cancer patients without paraneoplastic symptoms had these antibodies. Treatment of the tumour and/or immunomodulation did not alter the course of paraneoplastic cerebellar degeneration, but improved Lambert-Eaton myasthenic syndrome symptoms. At the time of death, in 60% of HuAb positive and 20% of HuAb negative paraneoplastic cerebellar degeneration patients, the tumour was either not evident or localized to the chest (P < 0.007); neurological disease was the cause of death of 65% HuAb positive paraneoplastic cerebellar degeneration and 10% HuAb negative paraneoplastic cerebellar degeneration patients (P < 0.001). (ABSTRACT TRUNCATED)

Effect of Lambert-Eaton myasthenic syndrome antibodies on autonomic neurons in the mouse

Somatic muscle weakness and autonomic symptoms characterize the autoimmune Lambert-Eaton myasthenic syndrome (LEMS). The former results from IgG autoantibody-mediated down-regulation of P/Q-type voltage-gated calcium channels at motor nerve terminals and consequent reduction in acetylcholine release; the basis for the autonomic symptoms is unknown. Using omega-conotoxins GVIA and MVIIC and omega-agatoxin IVA that block N-, Q-, and P-type channels, we investigated ex vivo the calcium channels subserving transmitter release from postganglionic parasympathetic neurons in the bladder and from postganglionic sympathetic neurons in the vas deferens of mice injected with IgG from LEMS patients or from controls. Calcium influx through N-, P-, and Q-type channels subserved transmitter release from parasympathetic and sympathetic neurons in control mice. In test mice, the component of transmitter release subserved by P-type channels was abolished by four of four LEMS IgG preparations, that subserved by Q-type channels was significantly reduced by three, and that subserved by N-type channels by one. Thus, LEMS IgG impairs transmitter release from parasympathetic and sympathetic neurons through down-regulation of one or more subtypes of voltage-gated calcium channels. The results suggest that antibody-mediated interference with specific ion channel function may also underlie autonomic dysfunction occurring in other autoimmune diseases.

Gastrointestinal manifestations of progressive systemic sclerosis

Management of patients with progressive systemic sclerosis requires a thorough gastroenterological examination and a profound knowledge of possible gastrointestinal manifestations of the disease. The esophagus is the gastrointestinal segment most often involved. Smooth muscle atrophy leads to a loss of esophageal peristalsis, a defect of the lower esophageal sphincter, and gastric hypomotility, thus predisposing to severe reflux esophagitis. A rational diagnostic approach includes standard manometry and endoscopy. The prevention of strictures is the main aim of therapeutic efforts that may consist of lifestyle changes, prokinetic drugs, long-term application of proton pump inhibitors, and, if inevitable, surgical intervention. Involvement of the small intestine and colon is less common but may lead to life-threatening complications like chronic pseudoobstruction or pneumatosis cystoides intestinalis. The main therapeutic options consist of antibiotics for bacterial overgrowth and nutritional supplementation. Recently, a preliminary study with octreotide yielded promising results. Anorectal dysfunction can lead to fecal incontinence or rectal prolapse.

[Infections and vasculitis]

Vasculitides are rare diseases characterized by inflammation of blood vessels. According to diameter of the blood vessels involved in the inflammatory process, the clinical presentation and the histological appearance, different vasculitic syndromes may be distinguished. Primary vasculitides are of unknown origin while secondary vasculitides may be caused by drugs, malignancy or infection. Panarteriitis nodosa caused by chronic Hepatitis B and mixed cryoglobulinemia secondary to chronic Hepatitis C are classical examples of vasculitides triggered by infections. However, these are rare complications of chronic viral hepatitis. Patients infected by HIV frequently suffer from vasculitis, which may be caused by opportunistic infections and by defects in immune regulation. In numerous case reports, various other infectious particles have been reported to cause different forms of vasculitis, either by direct infection of endothelial cells or by induction of an immunologic process leading to blood vessel destruction. Immunologically mediated vasculitis secondary to infection may be due to a predisposing reactivity of the patient's immune system. After successful treatment of the infection, the vasculitis usually subsides. Therefore, all patients with vasculitis should be evaluated for underlying infection.

Estimation of the cut-off value in cardiovascular autonomic nervous function tests: not-age-related criteria or the age-related 5th percentile

The aim of the study was to estimate the cut-off value of cardiovascular tests using not-age-related criteria or the age-related 5th percentile in 165 diabetic patients. The cANP, pANP, and smNP were assessed using previously recommended standardized test procedures. Prevalence of overall definite (borderline) cANP was 35.2% (23.0%) when using the 5th percentile or 16.4% (27.9%) when using not age-related criteria (p for the difference < 0.0001) (p = 0.3205). Prevalence of pANP was 54.0% and of smNP 37.0%. Concerning cANP, the number of test results below the 5th percentile (N5) correlated significantly with the number of abnormal test results using not age-related criteria (Nnar) (p < 0.000001) but the slope of the regression line differed substantially from 1. Using the 5th percentile as the cut-off value for cANP testing, sensitivity and specificity were calculated for not age-related criteria for respiratory sinus arrhythmia (90.5%, 80.2%), Valsalva test (30.4%, 98.0%), lying-to-standing test (46.3%, 98.7%), orthostatic systolic blood pressure fall (69.0%, 78.3%), and overall definite cANP (44.8%, 92.8%). The statistical analysis revealed that the age-related 5th percentile is superior to the not-age-related cut-off values in diabetic patients. We therefore suggest that age-related normal values (percentiles) have to be applied when cANP is estimated.

High prolactin and low dehydroepiandrosterone sulphate serum levels in patients with severe systemic sclerosis

The aim was to determine serum levels of prolactin (PRL) and dehydroepiandrosterone sulphate (DHEAS), and to demonstrate a link between PRL or DHEAS and soluble immune mediators in patients with systemic sclerosis (SSc) with different degrees of disease-induced organ involvement. Thirty-one patients with SSc were studied to evaluate 18 possible disease manifestations. In the serum, PRL, DHEAS and soluble immune mediators were determined by ELISA. Compared to SSc with <9 disease manifestations, patients with > or =9 disease manifestations had higher PRL (P = 0.044), higher soluble interleukin 2 receptor (sIL-2R, P = 0.004) and vascular cell adhesion molecule (sVCAM, P = 0.044), and lower DHEAS (P = 0.029). PRL (R(Rank) = 0.490, P = 0.003) and DHEAS (R(Rank) = -0.399, P = 0.013) were significantly correlated with the number of disease manifestations. The inverse correlation between PRL and DHEAS showed a trend (P = 0.059). PRL correlated with sIL-2R (R(Rank) = 0.553, P = 0.001) and sVCAM (R(Rank) = 0.520, P = 0.002). The number of disease manifestations and sIL-2R correlated significantly (R(Rank) = 0.463, P = 0.006). Psychometric variables to examine the presence of depression were not measured, but from the general aspect, the patients were not suffering from major depression which may have influenced our results. In conclusion, this study demonstrates the close association between DHEAS and, particularly, PRL and SSc severity and T-lymphocyte mechanisms.

Neuronal regulation of interleukin 6 secretion in murine spleen: adrenergic and opioidergic control

The PNS was anticipated to be involved in the modulation of immune responses. To study aspects of this neuronal-immune communication, a recently developed tissue slice method was used to study the effects of adrenergic and opioidergic transmitters on interleukin 6 (IL-6) secretion in the spleen. The alpha 2-adrenergic agonist p-aminoclonidine (10(-7) M) inhibited IL-6 secretion (control vs. p-aminoclonidine, 100.0 +/- 4.76 vs. 59.3 +/- 6.6% of control values; p < 0.001). The alpha 1-adrenergic agonist methoxamine (10(-8) M) also inhibited IL-6 secretion (100.0 +/- 4.8 vs. 71.5 +/- 3.8%; p < 0.001). The endogenous opioids beta-endorphin (10(-10) M), methionine-enkephalin (10(-9) M), and leucine-enkephalin (10(-9) M) inhibited IL-6 secretion as well (p = 0.0051, p = 0.0337, and p = 0.0226, respectively). Electrical stimulation of spleen slices inhibited IL-6 secretion (100.0 +/- 4.3 vs. 56.7 +/- 4.6% of control values; p < 0.001). The involvement of alpha-adrenergic and opioidergic molecules in this electrically induced inhibition was shown by the use of antagonists. Electrical inhibition of IL-6 secretion was attenuated by phentolamine (10(-7) M; p = 0.0345), by naloxone (10(-6) M; p = 0.0046), by cyprodime (10(-8) M; p = 0.0014), and by the combination of cyprodime (10(-7) M) plus phentolamine (10(-8) M; p < 0.0001). We conclude from the complementary studies that the inhibition of IL-6 secretion induced by electrical pulses was mostly mediated by alpha-adrenergic and mu-opioidergic endogenous transmitters.

Incidence of serum anti-P/O-type and anti-N-type calcium channel autoantibodies in the Lambert-Eaton myasthenic syndrome

The Lambert-Eaton myasthenic syndrome (LEMS) is an autoimmune disease in which autoantibodies are directed against voltage-gated calcium channels (VGCCs) at presynaptic nerve terminals. We first demonstrated the presence of P/Q-type and N-type VGCCs in digitonin extracts prepared from human and rabbit cerebellum using the specific ligands 125I-omega-conotoxin MVIIC (125I-omega-CmTx) and 125I-omega-conotoxin GVIA (125I-omega-CgTx), respectively. We then tested sera from 72 LEMS patients' 25 with proven small cell lung cancer (SCLC) and 66 healthy or other neurological, SCLC or autoimmune disease controls in an immunoprecipitation assay using 125I-omega-CmTx-labelled (P/Q-type) VGCCs in human cerebellar extract. Sixty-six of 72 LEMS serum samples (91.7%) were positive for the presence of VGCC antibodies, as defined as a titre greater than 3 standard deviations above the mean for the healthy controls (n = 22). Rabbit cerebellar extract as antigen gave similar results (r = 0.94, P < 0.001, n = 30). By contrast, only 24/72 (33%) LEMS sera were positive in the assay for anti-N-type VGCC antibodies using 125I-omega-CgTx. All these 24 were also positive in the 125I-omega-CmTx assay. All healthy and disease control sera were negative in both assays. The anti-P/Q-type VGCC antibody titres did not correlate with an electrophysiological index of disease severity across individuals; however, longitudinal studies in a LEMS patient with SCLC receiving chemotherapy, and in a non-SCLC LEMS patient receiving immunosuppressive therapy showed an inverse relation between antibody titre and disease severity. These results support the view that anti-P/Q-type VGCC antibodies are implicated in the motor disorder in LEMS, and show that the omega-CmTx radioimmunoassay is a highly specific and sensitive means of detecting them.

Relapsing polychondritis: clinical and immunogenetic analysis of 62 patients

OBJECTIVE

In this study we describe clinical and immunogenetic findings in 62 unselected patients with relapsing polychondritis.

METHODS

In a multicenter study, clinical data of 26 (41.9%) female and 36 (58.1%) male patients were collected. HLA-DR specificities were identified in 60, and the frequencies were compared with those in healthy controls.

RESULTS

The median age at the time of diagnosis was 46.6 years (range 17 to 86). 58 (93.5%) patients had auricular chondritis, 31 (50.0%) ocular symptoms, 35 (56.5%) nasal involvement. Involvement of joints (53.2%), respiratory system (30.6%), skin (24.2%), cardiovascular system (22.6%), central nervous system (9.7%), and kidneys (6.5%) was found as well. 22 (35.5%) patients had associated diseases such as systemic lupus erythematosus or rheumatoid arthritis. Susceptibility to relapsing polychondritis was significantly associated with HLA-DR4 (p < 0.001). There was no difference in the frequency or distribution of DRB1*04 subtype alleles between patients and healthy controls. The extent of organ involvement was negatively associated with HLA-DR6 (p < 0.011).

CONCLUSION

Immunogenetic findings as well as similarities and overlapping clinical symptoms with other autoimmune or rheumatic diseases suggest that immunological mechanisms play a major role in the pathogenesis of relapsing polychondritis.

Esophageal manometry in systemic sclerosis: screening procedure or confined to symptomatic patients?

The predictive value of esophagus-related symptoms for the diagnosis of esophageal dysmotility induced by systemic sclerosis (SSc) was prospectively evaluated in 50 consecutive patients with SSc. Patients were classified as symptomatic when either dysphagia or repeated episodes of heartburn were present. All patients underwent esophageal manometry; SSc-induced esophageal dysfunction was diagnosed when there was aperistalsis or marked hypocontractility of the distal two-thirds of the esophageal body. Twenty-nine patients (58%) had a history of esophagus-related symptoms, while 21 patients (42%) were asymptomatic. Compared to esophageal manometry, esophagus-related symptoms had a sensitivity of 64%, a specificity of 52%, a negative predictive value of 50% and a positive predictive value of 62% for the diagnosis of SSc-induced esophageal dysfunction. In conclusion, the association of esophagus-related symptoms and esophageal motility pattern is poor. As clinical management strategies depend on proof of esophageal dysfunction, screening examinations are mandatory in all patients with SSc.

Identification of phospholipase A2 and neurotoxic activities in the venom of the New Guinean small-eyed snake (Micropechis ikaheka)

The Papua New Guinean small-eyed snake (Micropechis ikaheka) is recognised as a cause of life-threatening envenoming in certain parts of New Guinea. The clinical features suggest the presence of toxins acting at the neuromuscular junction and on muscle. We have used the mouse phrenic nerve hemidiaphragm preparation, a phospholipase A2 assay, and 125I-neurotoxin-binding radioimmunoassays to look for toxic activities in the crude venom and in preliminary high-performance liquid chromatography (HPLC) fractions. Micropechis ikaheka venom at 1 and 3 micrograms/ml completely abolished nerve-evoked muscle twitch within 70 min at 37 degrees C. There was also a sustained contracture of the muscle and some reduction in twitch tension evoked by direct stimulation; these were explained by the presence of phospholipase A2 activity. The venom inhibited the binding of 125I-alpha-bungaro-toxin to detergent-extracted human muscle acetylcholine receptor (AChR), and inhibited acetylcholine receptor function in a muscle cell line. It also inhibited binding of 125I-omega-conotoxin GVIA to detergent-extracted human frontal cortex voltage-gated calcium channels, but this appeared to be dependent on the phospholipase A2 activity. Identification of the main neurotoxic fractions following HPLC are shown.

Autoantibodies against the protease inhibitor calpastatin: a new risk factor for venous thrombosis?

Autoantibodies reactive against human calpastatin were detected by screening a cDNA expression library with the serum of a 53 year old white female patient with a history of venous thrombosis and suspected antiphospholipid syndrome. When further sera were analyzed it could be shown that > 90% of calpastatin autoantibodies, detected by Western blotting against the partial calpastatin clone, react with the C-terminal amino acids of the protein. Therefore, an ELISA based on a synthetic peptide containing the C-terminal 27 amino acids of calpastatin was developed and 205 healthy blood donors and 138 random sera from hospital patients were analyzed. A total of 11 sera (3.2%) were positive with no significant difference between the two groups (7/205 and 4/138). In 80 consecutive patients with a history of venous thrombosis 9 positive sera (11.3%; p < 0.01 vs. blood donors, p < 0.02 vs. hospital patients) were detected. Our results indicate that autoantibodies against calpastatin may constitute a so far unknown risk factor for venous thrombosis.

Autoimmunity to ion-channels and other proteins in paraneoplastic disorders

Paraneoplastic neurological disorders are rare conditions caused by immune responses against tumour antigens that cross-react with neuronal antigens. In the past year, there have been advances in the definition of some of the antigens that are recognized by patients' antibodies, and new observations on the results of passive and active immunization against the antigens.

Neuroimmune control of interleukin-6 secretion in the murine spleen. Differential beta-adrenergic effects of electrically released endogenous norepinephrine under various endotoxin conditions

In a previous study we demonstrated a superfusion technique which allows for investigation of nerve-immune cell interaction in murine spleen. We demonstrated that under septic-like conditions in the presence of bacteria and lipopolysaccharide (LPS), electrically induced inhibition of interleukin 6 (IL-6) secretion was attenuated by the beta-adrenergic antagonist propranolol. This effect was now investigated more closely under various endotoxin conditions in order to dissect effects of bacteria and endotoxin: (A) bacteria-rich conditions (without penicillin/streptomycin [P/S] and without LPS), (B) LPS-enriched conditions (with P/S and with LPS), and (C) bacteria-free conditions (with P/S and without LPS). Under bacteria-rich conditions, norepinephrine (Emax = 10(-6) M, p = 0.012) and isoproterenol (Emax = 10(-6) M, p = 0.048) concentration-dependently inhibited IL-6 secretion from murine spleen slices in contrast to bacteria-free conditions. In a bacteria-free environment the beta-adrenergic antagonist propranolol did not attenuate the electrically induced inhibition of splenic IL-6 secretion. The insertion of bacterial filters in front of the superfusion chambers to avoid direct contact between bacteria and cells increased the electrically-induced inhibition of IL-6 secretion (p = 0.0036). Added LPS did not change the electrically-induced release of norepinephrine from presynaptic nerve terminals in murine spleen. The study demonstrates two different beta-adrenergic effects on IL-6 secretion of murine spleen slices under bacteria-rich or bacteria-free conditions.

Effects of intravenous immunoglobulin on muscle weakness and calcium-channel autoantibodies in the Lambert-Eaton myasthenic syndrome

Intravenous immunoglobulin improves many antibody-mediated autoimmune disorders, but its mode of action is unknown. We investigated its effects on muscle strength and on the serum titer of the calcium-channel autoantibodies that are likely to be pathogenic in the Lambert-Eaton myasthenic syndrome (LEMS). In a randomized, double-blind, placebo-controlled crossover trial, serial indices of limb, respiratory, and bulbar muscle strength and the serum titer of calcium-channel antibodies in nine patients were compared over an 8-week period, using the area-under-the-curve approach, following infusion on two consecutive days of immunoglobulin at 1 g/kg body weight/day (total dose 2.0 g/kg body weight) or placebo (equivalent volume of 0.3% albumin). Calcium-channel antibodies were measured by radioimmunoassay using 125I-omega-conotoxin MVIIC. Direct anti-idiotypic actions of immunoglobulin were tested in this assay. Immunoglobulin infusion was followed by significant improvements in the three strength measures (p = 0.017 to 0.038) associated with a significant decline in serum calcium-channel antibody titers (p = 0.028). Improvement peaked at 2 to 4 weeks and was declining by 8 weeks. Mean serum titers were unchanged at 1 week, however, and direct anti-idiotypic neutralization by immunoglobulin was not demonstrable in vitro. We conclude that immunoglobulin causes a short-term improvement in muscle strength in LEMS that probably results from the induced reduction in calcium-channel autoantibodies. The reduction is not due to a direct neutralizing action of the immunoglobulin, but a delayed anti-idiotypic action cannot be excluded. Improvement following intravenous immunoglobulin in other autoantibody-mediated disorders may similarly be associated with decline in levels of pathogenic autoantibodies.

Atrial natriuretic factor and digoxin-like immunoreactive factor in diabetic patients: their interrelation and the influence of the autonomic nervous system

In diabetic patients, several factors contribute to volume expansion and have to be counteracted by humoral and neuronal feedback control systems. We investigated N-terminal proatrial natriuretic factor (ANF1-98) and digoxin-like immunoreactive factor (DLIF), which are two counteracting hormones, and their interrelationship, with additional consideration given to autonomic nervous function in diabetic patients. ANF1-98 and DLIF were measured in 64 diabetic patients. Autonomic nervous function was assessed using nine autonomic nervous function tests. The patients were subdivided into two groups, one with four or more (group 1) and one with less than four abnormal results in autonomic function tests (group 2). Compared with group 2, group 1 demonstrated detectable DLIF levels less often (17.2 vs. 45.7, P = 0.0195) and increased levels of ANF1-98 (mean +/- SEM: 850.0 +/- 108.8 vs. 554.8 +/- 45.9 pmol/L, P = 0.0099). However, the groups did not differ in blood pressure, daily sodium, and daily potassium excretion. The number of abnormal autonomic function tests correlated significantly with ANF1-98 (P = 0.0002). In patients with detectable DLIF, DLIF correlated with ANF1-98 (P = 0.0080). These results demonstrate close interactions between the autonomic nervous system and the two natriuretic hormones. In patients with autonomic nervous dysfunction, higher levels of ANF may possibly compensate for the lack of the natriuretic DLIF to counteract hypertension and chronic volume expansion.

Gallbladder motility in systemic sclerosis

In 20 patients with systemic sclerosis (SSc) and 24 healthy controls, gallbladder motility was evaluated by abdominal ultrasonography after stimulation by a standard liquid meal. Results from patients with normal and disturbed oesophageal function were analysed separately in order to investigate the significance of gallbladder motility as a parameter for gastrointestinal involvement in SSc. All patients showed a marked decrease in gallbladder size after stimulation (patients 61 +/- 13%; controls 48 +/- 12%). Patients with oesophageal dysfunction (n = 12) had a slightly lower gallbladder contraction (maximal decrease = 58 +/- 13%) when compared to patients with normal oesophageal function (n = 8; 66 +/- 13%); however, this difference was not statistically significant. Gallbladder motility in patients with SSc was not reduced when compared with healthy controls. SSc-induced oesophageal dysfunction was not associated with impaired gallbladder motility. Thus, measurement of gallbladder emptying is not a helpful tool when looking for gastrointestinal involvement in SSc.

Distinct patterns of immunoglobulin classes and IgG subclasses of autoantibodies in patients with inflammatory bowel disease

OBJECTIVE

The pathophysiological significance of autoantibodies in inflammatory bowel diseases (IBD) is still unclear. To assess specific immunological abnormalities we examined the distribution and restriction of immunoglobulin classes and subclasses of anti-neutrophil cytoplasmic antibodies (ANCAs) in ulcerative colitis and of antibodies to pancreatic juice (APJs) in Crohn's disease.

METHODS

We tested 62 sera of patients with ulcerative colitis and 184 sera of patients with Crohn's disease for their immunoglobulin class and IgG subclass distribution of ANCAs (in ulcerative colitis patients) and APJs (in Crohn's disease patients) by fluorescence isothiocyanate (FITC)-labelled anti-human antibodies in an immunofluorescence assay with human granulocytes or pancreas as substrate. Twenty-five patients with Wegener's granulomatosis were used for comparison.

RESULTS

In ulcerative colitis ANCAs were found in 74% of the patients. They were predominantly of the IgG (96%) and IgA class (37%). In Crohn's disease APJs (present in 28% of the cases) were of the IgG (98%) and IgA class (71%). ANCAs in ulcerative colitis were of the IgG1 (73%) and IgG3 (5%) subclasses, APJs in Crohn's disease of the IgG1 (94%), IgG2 (20%) and IgG3 (2%) subclasses. The immunoglobulin class and IgG subclass distributions of ANCAs and APJs resembled the changes in total immunoglobulin classes and IgG subclasses in ulcerative colitis or Crohn's disease.

CONCLUSION

The immunoglobulin classes and IgG subclasses of autoantibodies in ulcerative colitis and Crohn's disease differ from each other and from the distribution of autoantibodies in vasculitic diseases (Wegener's granulomatosis, microscopic vasculitis, systemic lupus erythematosus). These alterations reflect specific pathophysiological features of ulcerative colitis and Crohn's disease.