A new helicoid-type sequential oligopeptide carrier (SOC(n)) for developing potent antigens and immunogens

A new class of sequential oligopeptide carriers (SOC(n)) for anchoring antigenic/immunogenic peptides has been constructed. The carrier, formed by the repetitive Lys-Aib-Gly moiety, is designed to display a predetermined 3D structure, so that the attached peptides would obtain a defined spatial orientation. Conformational analysis showed that SOC(n) adopt a distorted 3(10)-helical structure, while the coupled peptides preserve their original 'active' structure. Coupling to the carrier may also result to the enhancement of one conformer of the anchored peptide. It is concluded that the structure of SOC(n) offers an optimal presentation of the attached peptides, so that potent antigens or immunogens are generated.

Peptide carriers: A helicoid-type sequential oligopeptide carrier (SOC(n)) for multiple anchoring of antigenic/immunogenic peptides

A new peptide carrier with three-dimensional predetermined structural motif has been constructed by the repetitive Lys-Aib-Gly moiety. The sequential oligopeptide carrier (SOC(n)), (Lys-Aib-Gly)(n), adopts a distorted 3(10)-helical conformation and the Lys-N(epsilon)H(2) anchoring groups exhibit defined spatial orientations. Conformational analysis of the SOC(n) conjugates showed that the coupled peptides retain their initial "active" structure, while prevalence of one conformer was also observed. It is concluded that the beneficial structural elements of SOC(n) induce a favorable arrangement of the conjugated peptides, so that potent antigens and immunogens are generated.

Antibodies to beta 2-glycoprotein-I: urea resistance, binding specificity, and association with thrombosis

The aim of the present study was to evaluate the urea resistance and binding characteristics of anti-beta 2-glycoprotein I (anti-beta 2GPI) antibodies using standard anticardiolipin (aCL) and anti-beta 2GPI enzyme immunosorbent assays (ELISAs). Sera from patients with antiphospholipid syndrome (APS) (n = 22) and non-APS (n = 24), positive in a standard aCL ELISA, were tested in an anti-beta 2GPI ELISA performed in polystyrene-irradiated ELISA plates. Urea resistance aCL and anti-beta 2GPI ELISAs were performed by measuring the ability of antibodies to recognize antigen in the presence of 2 M urea. The serum dilution after urea treatment (D) expressed as a percentage of the serum dilution without urea treatment (D(o)) corresponding to the same optical density was defined as residual activity (RA = 100 D/D(o)). The higher the RA, the higher the resistance of the antibodies to urea. APS compared to non-APS sera had higher aCL binding (absorbance values ranging between 0.180 and 1.400; median, 0.717 vs 0.120-1.273; median, 0.250, respectively; P < 0.004). Six APS patients' sera had low aCL levels but they expressed RA > or = 30%. Anti-beta 2GPI antibodies were detected in 15 of 22 APS vs 3 of 24 non-APS patients (P < 0.03); RA > or = 30% was detected in 15 of 22 APS vs 1 of 23 non-APS patients (P < 0.004). Using a CL affinity column, antibodies were purified from three APS anti-beta 2GPI negative and three non-APS anti-beta 2GPI-positive patients and tested in a aCL ELISA, using highly purified bovine serum albumin (BSA) as a blocking agent (modified ELISA); reactivity was not detected in two APS and one non-APS sera. On the contrary, the reactivity of the purified antibodies was high when beta 2GPI was incubated with CL in the ELISA plates; thus some anti-beta 2GPI negative sera from APS patients recognized the CL/beta 2GPI complex, rather than CL or beta 2GPI alone. In conclusion, anti-beta 2GPI antibodies are common in the APS patients, but a number of such patients recognize the CL/beta 2GPI complex and not CL or beta 2GPI. Antibodies to either beta 2GPI or the CL/beta 2GPI complex derived from APS sera present a high resistance to urea. Anti-beta 2GPI antibodies of low urea resistance exist in a minority of non-APS patients with autoimmune disease.

A major Sm epitope anchored to sequential oligopeptide carriers is a suitable antigenic substrate to detect anti-Sm antibodies

A sensitive, highly reproducible, solid-phase enzyme immunoassay (ELISA), was developed in order to investigate whether the synthetic heptapeptide PPGMRPP-a major epitope of the Sm autoantigen-anchored in five copies to a sequential oligopeptide carrier (SOC), [(PPGMRPP)5-SOC5] is a suitable antigenic substrate to identify anti-Sm/antibodies. Sera with different autoantibody specificities [45 anti-Sm, 40 anti-U1RNP, 40 anti-Ro (SSA)/La(SSB) positive, 21 Antinuclear antibody positive, but negative for antibodies to extractable nuclear antigens (ANA + /ENA - ) and 75 normal human sera, ANA negative] and 75 sera from patients with rheumatoid arthritis (RA) were tested for anti-(PPGMRPP)5-(SOC)5 reactivity in order to evaluate the specificity and sensitivity of the method to detect anti-Sm antibodies. RNA immunoprecipitation assays for the detection of anti-Sm and anti-U1RNP antibodies and counter immunoelectrophoresis (CIE) for the detection of anti-Ro(SSA) and anti-La(SSB) antibodies were used as reference techniques. The sensitivity of the method was 98% and the specificity was 68% for the determination of anti-Sm antibodies, while for the determination of anti-Sm and/or anti-U1RNP reactivity (antibodies to snRNPs) the corresponding values were 82% and 86%, respectively. In a comparison of the above assay with an ELISA, using Sm/U1RNP purified complex as immobilized antigen it was shown that the sensitivity of the anti-Sm/U1RNP ELISA in detecting anti-snRNPs was 74%; in addition sera with anti-Sm antibodies gave higher binding in the anti-(PPGMRPP)5-(SOC)5 ELISA compared with anti-Sm/U1RNP ELISA. Intra- and inter-assay precision was measured on four sera with reactivities extending into a wide range of absorbance values showed that the intra-assay coefficient of variation (CV%) ranged from 2.7 to 6 and the inter-assay CV% ranged from 9 to 14.5. These results indicate that the PPGMRPP peptide anchored to a pentameric SOC as a carrier is a suitable antigen for detecting anti-Sm antibodies and that the above ELISA is a rapid, reproducible and valuable screening method to test anti-Sm/U1RNP reactivities.

Hypofunction of the stress axis in Sjögren's syndrome

OBJECTIVE

To examine the functional integrity of the hypothalamic-pituitary-adrenal (HPA) and thyroid axes in Sjögren's syndrome (SS) via the assessment of basal and stimulated adrenocorticotropin (ACTH), cortisol, thyroid stimulating hormone (TSH), and prolactin levels.

METHODS

Pituitary function of the HPA axis was assessed by determining the basal plasma levels of ACTH in the late afternoon, as well as the ACTH released to ovine corticotropin releasing hormone (oCRH) stimulation; adrenal function was assessed by measuring plasma cortisol levels in the late afternoon at baseline and after release of the endogenous ACTH during oCRH stimulation. Basal and thyrotropin releasing hormone (TRH) stimulated levels of TSH and prolactin were also assessed. Healthy volunteers were used as controls.

RESULTS

Patients with SS, compared to controls, were characterized by significantly lower ACTH levels (pg/ml), (5.1 +/- 0.5 vs 11.4 +/- 1.5, respectively; p < 0.05) and cortisol levels (microg/ml), (2.4 +/- 0.6 vs 5.9 +/- 1.2, respectively; p < 0.05). Furthermore, a blunted pituitary and adrenal response to oCRH compared to controls was observed: peak plasma ACTH and cortisol levels for patients with SS were 46.2 +/- 5.4 pg/ml and 15.7 +/- 1.6 microg/ml, respectively, and for controls 61.5 +/- 3.8 and 19.6 +/- 0.7, respectively (p < 0.05). Basal TSH levels were significantly elevated in patients (1.3 +/- 0.3 microIU/ml vs 0.9 +/- 0.05 microIU/ml; p < 0.05).

CONCLUSION

The above findings indicate hypoactivity of the HPA axis in patients with SS. Further studies are needed to definitively identify the locus of the defects and assess the significance of the pattern of the perturbations to the pathogenesis and expression of SS.

Clinical features and evolution of antinuclear antibody positive individuals in a rheumatology outpatient clinic

OBJECTIVE

To identify individuals with antinuclear antibodies (ANA) not fulfilling criteria for systemic lupus erythematosus (SLE) or other connective tissue diseases (CTD); to describe their clinical and serological features, to identify factors indicating evolution to SLE.

METHODS

A case-control study, based on retrospective evaluation of clinical files. The cases were ANA positive individuals (n = 50) examined in a medical outpatient setting, for symptoms compatible with SLE, but not fulfilling SLE classification criteria. Two patients with SLE were matched to each case in terms of age at initial symptom onset and sex. Thyroid autoimmunity was assessed by detecting antithyroid antibodies. Fisher's exact test and conditional logistic regression were used to evaluate the predictive ability of initial findings for SLE development.

RESULTS

ANA positive individuals suspected of having a CTD present a wide variety of symptoms and findings, usually at the 4th to 5th decade of life. Antibodies to Sm and U1RNP were absent; anti-Ro(SSA) and anti-La(SSB) occurred in 6%, while anti-dsDNA occurred in less than 10% of the cases. Arthritis, butterfly and discoid rash, Raynaud's phenomenon, and anti-Ro/SSA antibodies are the initial findings indicating evolution to SLE. Hematological abnormalities such as leukopenia and thrombocytopenia as well as constitutional symptoms such as easy fatigue and arthralgias are not associated with evolution to SLE. Antithyroid antibodies were detected in 16% of the cases and 2.3% of controls.

CONCLUSION

ANA may connote a form of systemic autoimmunity that is expressed as a wide variety of complaints, even in the absence of a definite diagnosis of CTD. Arthritis, rash, Raynaud's phenomenon, and anti-Ro/SSA antibodies indicate evolution to SLE. Autoimmune thyroid disease occurs in ANA positive individuals not fulfilling SLE classification criteria rather than in patients with SLE.

Therapy of Sjögren's syndrome. New aspects and future directions

Therapy of Sjögren's syndrome remains empirical and symptomatic. The main goals are to treat the disease related features, especially sicca manifestations, since the immunosuppressive therapy has not given promising results. For the treatment of keratoconjunctivitis sicca: local stimulators of tear secretion, protective bicarbonate buffered solutions, replacement therapy or supportive operative procedures should be tried. For oral manifestations: stimulators of salivary secretion such as pilocarpine, or agents changing the consistency of saliva such as bromhexine orally should be tried. Saliva substitutes have a transient effect. Frequent ingestion of sugar free liquids may help. Oral hygiene is important to avoid oral candidiasis and dental caries. Treatment of parotid gland swelling is not necessary. Pulmonary manifestations include pulmonary infiltrates in perialveolar areas, nodular or cavitary lesions which may represent lymphoma. Hilar adenopathy, solid or cavitary lesions should be biopsied. In case of vasculitis prednisolone 1 mg/kg/day with progressive tapering should be tried. Renal involvement is manifested mainly as interstitial disease. Administration of NaHCO3 or sodium citrate is important to prevent acidosis and nephrocalcinosis. Vasculitis, when it is of the leukoclasic form, does not need therapy; when it is manifested with severe major organ involvement corticosteroids and/or cytotoxic therapy should be tried. Lymphoma is treated as in the patients without Sjögren's in close collaboration with the oncology department.

Evidence for non-adaptive immune response in HIV infection

Increased levels of soluble forms of adhesion molecules such as intercellular adhesion molecule 1 (ICAM-1) and E-selectin have been found in the sera of HIV-infected patients and have been associated with disease progression. The aim of the present study was to investigate whether this phenomenon reflects activation of the non-adaptive immune response in HIV infection. Fifty-one patients with HIV infection (42 men, nine women) were classified into two subgroups: those with HIV infection but without evidence of AIDS indicator conditions (HIV infected non-AIDS cases, n = 27) and those with AIDS (AIDS cases, n = 24). The activation of non-adaptive immune response was evaluated as the production of reactive oxygen species that cause lipid peroxidation, which was assessed by measuring thiobarbituric reactive substances (TBARS) using the thiobarbituric acid assay (TBA). Plasma levels of von Willebrand factor (vWF), measured by rocket immunoelectrophoresis, were used to show activation of endothelial cells even in the absence of any other causative agent, in these patients. TBARS levels in non-AIDS cases were significantly higher than in control subjects (n = 17) or AIDS cases (P < 0.001). The mean vWF levels were higher in AIDS cases than in non-AIDS cases or normal subjects (P < 0.05). TBARS levels remained significantly higher in non-AIDS cases after adjusting for age, CD4 T-cell and neutrophil counts, antiretroviral therapy and vWF plasma levels. The above findings indicate that in HIV infection, the virus per se is responsible for the increased oxidative stress that in turn activates various transduction pathways, may be leading to endothelial cell activation and shedding of adhesion molecules from the cell surface.

Idiopathic pulmonary fibrosis and pulmonary fibrosis in diffuse systemic sclerosis: two fibroses with different prognoses

Idiopathic pulmonary fibrosis and diffuse cutaneous systemic sclerosis (dSSc) involve the lung by a fibrotic process. In recent years, there has been increasing awareness that the natural history of these two types of pulmonary fibrosis might be different. The purpose of this study was to compare lung involvement in these two diseases in a prospective fashion in order to address differences in their clinical course. Forty-three consecutive patients, 18 with lone interstitial pulmonary fibrosis (lone IPF) and 25 with dSSc-IPF were evaluated clinically, radiologically and physiologically at the entry into the study and the evolution of their disease was contrasted by survival analysis. Patients with lone IPF compared with dSSc-IPF were characterized by male predominance (p < 0.001), older age at disease onset (p < 0.001), shorter disease duration (p < 0.001), more frequent crackles on auscultation and clubbing (p < 0.001 and p < 0.0001, respectively), more severe dyspnea (p < 0.0001) and more advanced radiological involvement (p < 0.0001). Functional indices presented comparable values and did not reach statistically significant differences except for the values of single breath CO diffusing capacity (p < 0.0001) and the PaO2 (p < 0.01) which was worse in patients with lone IPF. Finally 12 of the 18 patients with lone IPF died in 2.66 +/- 1.18 years from the onset of respiratory symptoms, while none of the dSSc-IPF patients had died 5.6 +/- 4.25 years from the first ever appearance of respiratory involvement (p < 0.001). In conclusion, although the two groups of patients were not at an absolutely comparable stage of their disease, a worse prognosis for patients with lone IPF seems to emerge from this study.

Safety and efficacy of recombinant gamma interferon in the treatment of systemic sclerosis

OBJECTIVE

To evaluate the safety and efficacy of recombinant gamma interferon (rIFN gamma) in the treatment of patients with systemic sclerosis.

METHODS

Sixteen patients with systemic sclerosis were treated with r-IFN gamma, 60 micrograms m-2 (low dose, n = 10) and 150 micrograms m-2 (high dose, n = 6), three times weekly in an open phase I/II trial of eight months duration. The patients were stratified in low and high dose according to the severity and the extent of scleroderma; the two groups were comparable.

RESULTS

The treatment was well tolerated. The most common side effects, almost certainly related to r-IFN gamma, were fever, chills, dizziness, headache, and severe flu-like syndrome with decreasing intensity with the time of treatment. Severe aphthous stomatitis (n = 1), ventricular tachycardia (n = 1), severe oesophageal ulcers due to gastro-oesophageal reflux (n = 1), disease exacerbation alone with frank arthritis and slight pericardial effusion (n = 1), and inability to conform to the requirements of the study (n = 1) were the reasons for discontinuing treatment. Side effects and degree of response were evident during the first five months of treatment. A significant decrease in mean skin thickness score was observed and was higher in the high dose group. Reactive oxygen species of peripheral neutrophils and soluble interleukin-2 receptor serum concentrations were higher than those of normal individuals at study entry and decreased in parallel with clinical improvement.

CONCLUSIONS

Treatment of systemic sclerosis patients with r-IFN gamma was relatively safe and well tolerated for doses as high as 150 micrograms m-2 three times weekly. Side effects and the degree of response can be seen during the first months of therapy and can be used as predictors of ultimate toxicity or response. The drug seems to be effective in treating cutaneous scleroderma.

Immunoreactivity and conformation of the P-P-G-M-R-P-P repetitive epitope of the Sm autoantigen

Anti-Sm antibodies are usually considered highly specific for systemic lupus erythematosus (SLE), while anti-U1 RNP antibodies are found in high titers in patients with mixed connective tissue disease (MCTD). The sequence P1-P-G-M-R-P-P7, present in three copies in the Sm (U1-U6 RNA-protein complex) autoantigen, is an important functional domain of the antigenic determinants. The immunoreactivity of this proline-rich repetitive epitope was investigated by testing sera with various autoantibody specificities for reactivity against this epitope, as well as its conformational properties by means of 1D and 2D 1HNMR spectroscopy. It was found that the P-P-G-M-R-P-P epitope is recognized mainly by anti-U1RNP and/or anti-Sm positive sera, but also by anti-Ro(SSA) (hY1RNA-protein complex) and anti-La(SSB) (hY1RNA-protein complex) positive sera, although these sera are negative for anti-U1RNP and anti-Sm. Conformational analysis of the proline-rich epitope in DMSO-d6 solution obtained from lyophilized aqueous solution at pH 5 showed the presence of at least three conformers. The main conformer A (62%) is stabilized by an ionic interaction between the guanidinium and the C-terminal carboxylate groups, and the Pro6-Pro7 peptide bond adopts the cis form. A type II beta-turn is also present in the N-terminal sequence (Pro1-Pro-Gly-Met4-) of this conformer. Conformer B (21%) is also stabilized by a similar ionic interaction, as in conformer A, while the NMR data indicate the absence of a folded structure in the N-terminal tetrapeptide of this conformer. Conformer C (17%) adopts a completely extended structure. The multiple conformers of the P-P-G-M-R-P-P may offer some explanation for the reactivity of sera with various autoantibody specificities against this epitope.

Predominance of IgM anti-U1RNP antibodies in patients with systemic lupus erythematosus

Anti-U1RNP antibodies occur in patients with mixed connective tissue disease (MCTD), systemic sclerosis (SSc), systemic lupus erythematosus (SLE) and other ill-defined connective tissue diseases. To associate the isotypes of anti-U1RNP antibodies with the diagnosis of the disease, namely SLE or MCTD, sequential sera of patients positive for anti-U1RNP antibodies by counterimmunoelectrophoresis (CIE) (32 with SLE, 35 with MCTD) were tested for IgG and IgM anti-U1RNP antibodies by enzyme-linked immunosorbent assay (ELISA) using affinity-purified U1snRNP complexes. Results from ELISA were confirmed by RNA precipitation. IgG RNA precipitation of HeLa cellular extracts was performed using the bulk of the IgG fraction removed from each serum after binding to protein A-Sepharose beads. IgM RNA precipitation was carried out on the IgM fraction of the serum bound to protein A-Sepharose-rabbit anti-human IgM immune complexes. RNAs were electrophoresed in 10.5% acrylamide-7 M urea gels and detected with the silver stain. ELISA showed that all sera were positive to IgG anti-U1RNP, while 12 of the 35 MCTD and 21 of the 32 SLE patients possessed IgM anti-U1RNP (P < 0.025). IgM anti-U1RNP reactivity was found during the follow-up in 20% of 44 sera from 17 MCTD patients and 68% of 112 sera from 23 SLE patients (P < 0.0001). IgG from all the sera precipitated U1RNPs. Eight of the MCTD sera also precipitated U2RNPs and 14 of the SLE sera U2 and/or U4/U6, U5 RNPs. IgM from MCTD sera did not precipitate URNPs, while IgM from SLE sera precipitated predominantly U1RNPs. These data suggest that IgM anti-U1RNP antibodies occur predominantly in patients with SLE. The occurrence of IgG anti-U1RNP without IgM is more frequent in MCTD.

Increased serum interleukin-1 beta during treatment of hyperthyroidism with antithyroid drugs

Serum interleukin-1 beta (IL-1 beta) and soluble interleukin-2 receptor (sIL-2R) levels were examined in patients with hyperthyroidism due to Graves' disease (GD) and toxic nodular goitre (TNG) before and during antithyroid drug therapy. A total of 32 patients were studied; 23 patients (14 with GD and nine with TNG) were in a hyperthyroid state (group A) and nine patients (four with GD and five with TNG) were in a euthyroid state, under carbimazole or methimazole treatment (group B). Ten hyperthyroid patients from group A (seven with GD and three with TNG) were also examined while euthyroid on treatment (Subgroup A). Serum was taken from all patients for the measurement of sIL-2R, IL-1 beta, total T4 (TT4), total T3 (TT3) and TSH concentrations. The results were compared with those from 30 normal controls. Serum sIL-2R levels were higher in Group A (671.3 +/- 74.0 U mL-1, mean +/- SE), than in Group B (214.1 +/- 61.8 U mL-1) and controls (149 +/- 14.8 U mL-1), P < 0.001. Similarly, the subgroup of 10 patients had higher levels of sIL-2R during the hyperthyroid phase than while euthyroid (P < 0.001). There was a positive correlation between sIL-2R values and levels of T4 and T3. In contrast, serum IL-1 beta levels were higher in Group B patients (197.5 +/- 39.2 pg mL-1) compared with those in Group A (66.5 +/- 17 pg mL-1, P < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Autoantibodies to HMG-17 nucleosomal protein in patients with scleroderma

Autoantibodies to HMG-17, a non-histone nucleosomal protein, were found in systemic lupus erythematosus (SLE), mixed connective tissue disease (MCTD) and ANA positive pauciarticular juvenile rheumatoid arthritis (JRA), but not in rheumatoid arthritis (RA). Using highly purified HMG-17 derived from porcine thymus, we tested sera from 50 patients with scleroderma for antibodies to HMG-17 by enzyme-linked immunosorbent assay (ELISA). There were 16 patients with diffuse cutaneous systemic sclerosis (dSSc) and 34 with limited cutaneous systemic sclerosis (1SSc) with age at disease onset 40.25 +/- 11.68 and 39.94 +/- 15.68 years, respectively, and disease duration 6.03 +/- 4.98 and 13.34 +/- 11.80 years, respectively (P < 0.0001). Anticentromere antibodies (ACA) were found in 65% of 1SSc patients but not in dSSc (P < 0.0001) while the prevalence of antinuclear antibodies (ANA) with other than ACA patterns did not differ in the two groups. Anti-HMG-17 antibodies occurred in 20 patients (40%), five with dSSc (31%) and 15 with 1SSc (41%). Twelve of the 20 HMG-17 positive patients were also positive for ACA (60%) but this association was not significant. No association was found between anti-HMG-17 and other antibody patterns. In conclusion, anti-HMG-17 antibodies occur in one third of scleroderma patients, do not discriminate scleroderma variants and are not associated with other autoantibodies.

Antiphospholipid syndrome: clinical and therapeutic aspects

The purpose of the present study was to evaluate patients with the antiphospholipid syndrome with particular attention to their initial clinical features, final diagnoses and the course of thrombotic events in association with therapy. The methodology applied was the following: retrospective analysis of 30 patient files (20 female, 10 male) with antiphospholipid syndrome (APS). Four types of therapy were evaluated for their efficacy to prevent thrombotic recurrences, aspirin 100 mg daily plus low-dose prednisone 10-15 mg daily, warfarin (with international normalized ratio 2 to 2.6), immunotherapy alone and no therapy. None of the patients was followed-up during pregnancy. The probability of thrombosis-free survival was estimated according to Kaplan-Meier method, while the statistical significance was tested by the log rank test. There were 21 patients with primary APS and 9 with secondary, 8 of whom had SLE and one patient who had primary Sjögren's syndrome. The age at onset and the disease duration did not differ between men and women, while patients with secondary APS had a longer disease duration than patients with primary APS, a finding indicating that SLE patients develop, for unknown reasons, APS a long time after the initiation of their disease. Twenty patients experienced recurrent thrombotic events (a total of 46 recurrences) of which 43 (93%) were identical to the first event. Thus, in the majority of the cases arterial were followed by arterial and venous by venous thrombotic events: a finding suggesting a tissue-related factor for initiation of thromboses.(ABSTRACT TRUNCATED AT 250 WORDS)

Systemic lupus erythematosus in Greece. Clinical features, evolution and outcome: a descriptive analysis of 292 patients

The purpose of this study was the descriptive analysis of patients with systemic lupus erythematosus (SLE) with a particular focus on initial clinical features, evolution and outcome of disease, prevalence of clinical and serological manifestations and identification of clinicoserological associations indicative of renal and CNS involvement. The methodology applied was the following: retrospective analysis of the clinical charts of 292 unselected patients (246 female (84.2%) and 46 male (15.7%)) with SLE examined between 1982 and 1992. Multivariate analysis and hierarchical log linear models were used to examine for clinicoserological associations. Descriptive analysis was based on the prevalence of main clinicoserological features and disease outcome. The outcome was examined on the basis of the number of flares, the presence of chronic renal failure, the presence of central nervous system (CNS) involvement with subsequent disability and deaths. Flares were considered the severe alterations in disease status, requiring additional therapy to be controlled. The disease begins most frequently in the second and third decade of life with cutaneous and joint manifestations, while renal and CNS involvement developed later. The prevalence of serious renal, pulmonary and CNS involvement as well as the prevalence of RF, anti-Sm and anti-nRNP antibodies remain low. Multivariate analysis revealed the associations of renal involvement with leukopenia and serositis, of anti-Sm with leukopenia, of secondary Sjogren's syndrome with RF and of thromboembolic events with anticardiolipin antibodies. Patients with childhood onset SLE have a higher tendency for developing renal involvement than adult onset SLE patients. In addition, anti-Ro(SSA) antibodies were associated with anti-La(SSB) and RF, while anti-Sm antibodies were associated with anti-nRNP and RF. Flares occurred with a frequency of 0.07 per patient per year. Only 63.6% of flares were accompanied by positive anti-dsDNA reactivities. Reported deaths were 0.0047 per patient per year. Hierarchical log linear models indicated that the main variables of the disease were sufficient to describe our disease model and that the order of the interaction between the variables was insignificant. We conclude that the prevalence of various clinical features associated with SLE is similar, although the prevalence of CNS and pulmonary involvement as well as anti-Sm and anti-nRNP antibodies are less prominent in Greek SLE patients than that reported in the literature. The various clinicoserological associations detected do not appear to be of major significance as they are not powerful enough to subgroup the disease.

Patients with anticentromere antibodies, clinical features, diagnoses and evolution

The sera of 1373 patients derived from a random population of 2627 individuals examined in a rheumatology outpatient clinic were found to be positive for antinuclear antibodies (ANA). Forty-seven of 1373 ANA positive patients (3.42%) presented a pattern of anticentromere antibodies (ACA), and of these 41 were followed-up. The predominant clinical features among ACA positive patients were Raynaud's phenomenon, arthralgias, scleroderma affecting the hands, feet, face and forearms, telangiectases and pulmonary involvement. There were 26 patients (64%) with limited cutaneous systemic sclerosis (lSSc), seven with primary Sjögren's syndrome (Ss) (17%), five with idiopathic Raynaud's phenomenon (IRPh) (12%) and three (7%) with other diseases. The lSSc subset was characterized by a significantly younger age for disease onset than for the IRPh patients. The Raynaud's phenomenon of lSSc patients lasted for many years before the onset of scleroderma, while their pulmonary involvement was mild and subclinical. The Ss patients with ACA were characterized by a lower incidence of parotid gland enlargement and anti-La (SSB) antibodies than described in the literature. Finally, the presence of ACA correlates with the clinical criteria proposed for the diagnosis of lSSc.

Antibodies to phosphatidylethanolamine in antiphospholipid syndrome and systemic lupus erythematosus: their correlation with anticardiolipin antibodies and beta 2 glycoprotein-I plasma levels

The sera patients with systemic lupus erythematosus (SLE) and antiphospholipid syndrome (APS) were tested, by ELISA, for antibodies to phosphatidylethanolamine (aPE), as well as to cardiolipin (aCL) and compared to healthy blood donors (HBD). Both, SLE and APS patients presented a higher titre of IgM-aPE antibodies than normals, while the IgG and IgA aPE reactivity did not differ. APS patients were characterized by higher IgM-aPE antibody titres than SLE patients. In contrast, the predominant isotype of aCL antibodies in APS patients was IgG. The IgM aPE reactivity was correlated with IgM aCL reactivity, while no correlation was observed between the total IgM values and IgM-aPE binding units of sera tested. Since it was shown that beta 2-glycoprotein-I (beta 2-GPI) contributes to a complex antigen by binding to phospholipids and that this antigen is recognized by antiphospholipid antibodies from autoimmune patients, sera beta 2-GPI levels were measured and correlated to aCL and APE activity. Although APS patients had higher beta 2-GPI levels than SLE patients, no correlation was found between the beta 2-GPI levels and IgG/IgM aCL and IgM-aPE reactivities a finding suggesting that in addition to beta 2-GPI, other cofactors for aPE antibodies may exist. These findings indicate that aPE and aCL antibodies co-exist and that the IgM-isotype is predominant in APS. In addition, the IgA and IgG aPE antibodies appear to occur in low titres in these patients, as well as in normals and may exist as natural autoantibodies. We suggest that the high IgM-aPE antibodies may be viewed as a thymus independent process.

Patients with anticardiolipin antibodies with and without antiphospholipid syndrome: their clinical features and beta 2-glycoprotein-I plasma levels

The clinical and serological features of 38 aCL-positive patients were compared to those of 45 aCL-negative patients. A significantly higher incidence of thrombophlebitis and livedo reticularis was found in aCL-positive patients. There were 13 aCL positive patients with thrombophlebitis and/or arterial thromboses and these 13 patients were designated as having the antiphospholipid syndrome (APS) while the remaining 70 patients were diagnosed as having Systemic Lupus Erythematosus (SLE). APS patients also had a high incidence of arterial occlusions, recurrent abortions and strokes compared to SLE patients. Patients with high levels of IgG-aCL were more likely to have APS, while patients with low levels of IgG-aCL or IgM-aCL only were more likely to have SLE without the clinical features of APS. Since aCL antibodies have recently been shown to interact with a phospholipid-binding plasma protein beta 2-glycoprotein-I (beta 2-GPI), we measured the beta 2-GPI levels in these patients and found that beta 2-GPI levels are significantly higher in APS compared to SLE patients negative for aCL antibodies. Since beta 2-GPI is known to exert multiple effects on coagulation processes the interaction of aCL antibodies with this glycoprotein may play a pathogenic role in APS.

Rheumatoid arthritis in south-east Europe

The clinical, serological and immunogenetic studies of RA in mediterranean countries and other small tribal groups have added some more information that is valuable in understanding the pathogenesis of RA. However, the immunogenetic studies seem to be more helpful in understanding the mechanisms of initiation of disease and its dissimilarities in different ethnic groups than in discovering its cause. It should also be stressed that, in addition to genetic factors, other factors may influence disease expression. This proposal was supported by a study from Africa which revealed an increasing incidence and severity of RA in rural compared with urbanized African populations (Brighton, 1987). Thus, the variability factor influencing disease expression may lie in the environment (Woodrow, 1988).

Chorea as a manifestation of the antiphospholipid syndrome in childhood

Chorea has been related to the presence of antiphospholipid antibodies (a-PL) in the context of systemic lupus erythematosus (SLE). Here we report the case of a 13-year-old girl with a-PL antibodies, who had developed thrombophlebitis at the age of 11 years and chorea two years later, in the absence of clinically evident SLE. Serological tests revealed a false positive test for syphilis, a prolonged activated partial thromboplastin time, hypocomplementaemia and positive anti-DNA antibodies.

D-penicillamine toxicity in Greek patients with rheumatoid arthritis: anti-Ro(SSA) antibodies and cryoglobulinemia are predictive factors

Sixty-two consecutive patients, with rheumatoid arthritis (RA) who received D-penicillamine were studied retrospectively to identify predictive risk factors for D-penicillamine toxicity. Thirty-two developed side effects, while 30 did not. The clinical picture in both groups was similar, but the group with D-penicillamine toxicity was characterized by a high incidence of anti-Ro(SSA) antibodies (p less than 0.01) or circulating cryoglobulins (p less than 0.001). The presence of anti-Ro(SSA) antibodies was not correlated with the presence of circulating cryoglobulins (p greater than 0.5), while the coefficient of contingency (C) between anti-Ro(SSA) and cryoglobulins was 0.131. Men were predisposed to express more renal pathology (p less than 0.025), while anti-Ro(SSA) positive patients with RA more often expressed rashes (p less than 0.0001) and acute febrile reactions (p less than 0.05) than anti-Ro(SSA) negative patients. These observations should be considered when making therapeutic decisions at least for Greek patients with RA.

Circulating antibodies to prothymosin alpha in systemic lupus erythematosus

Autoantibodies to prothymosin alpha, an immunoactive protein that exists in a large variety of mammalian tissues, were found to be present in patients with systemic lupus erythematosus (SLE) by a new, sensitive, and specific anti-prothymosin alpha ELISA. The antigen was prothymosin alpha, purified by high-pressure liquid chromatography from goat spleen extracts. Sera from 44 SLE patients and 276 healthy individuals were screened for the presence of anti-prothymosin alpha activity; 18% of SLE sera were found to be positive, compared with 1.8% of control sera. This anti-prothymosin alpha activity appears to be idiotypically distinct from either anti-thymosin alpha 1 activity or anti-dsDNA activity, as demonstrated by inhibition experiments. Significant positive correlation exists between anti-prothymosin alpha and anti-dsDNA activities of SLE sera (r = +0.596, n = 36, P less than 0.001), while no correlation was observed with the clinical activity (X2 = 1.239, 0.1 less than P less than 0.5) or with complement levels C3 and C4.