Immunological markers of the subsets of systemic scleroderma and its overlap.

The studies performed repeatedly in 298 cases of systemic scleroderma (SSc) disclosed high prevalence of antinuclear antibody (in about 95% of the cases) with the use of HEp-2 cells as the substrate for indirect immunofluorescence method. Anticentromere antibody (ACA) was found in 25% of acrosclerosis cases, but in 50% of patients with cutaneous involvement limited to the digits, i.e. almost without cutaneous indurations. The visceral involvement was comparable in cases positive and negative for ACA, and a follow-up of these patients showed that the course, although protracted, was not always mild as previously believed. Scl 70 antibody proved to be a most characteristic marker of SSc, appearing in about 87% of diffuse variety and in above 50% of acrosclerosis cases. The most important finding was the detection of the coexistence of ACA and Scl 70 antibody in 10 of 180 cases studied by three methods: indirect immunofluorescence, double immunodiffusion, (for Scl 70) and immunoblotting with recombinant kinetochore antigen for ACA and recombinant Topoisomerase I antigen for Scl 70 antibody. These antibodies, believed to be mutually exclusive, are most often missed due to masking effect on HEp-2 cells by the stronger antibody, usually Scl 70. Its detection proved to be possible by evaluation of different serum dilutions and several cell mitoses, and confirmed by immunoblotting with recombinant antigens. Of practical significance are the clinical correlations between Pm-Scl antibodies, showing homogeneous nucleolar staining on HEp-2 cells, and overlap or atypical SSc cases with concomitant muscle involvement. This antibody was found to have a surprisingly high association with atypical SSc or scleromyositis of children.     

HLA-G genotype and HLA-G expression in systemic lupus erythematosus: HLA-G as a putative susceptibility gene in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune disease mainly mediated by the deposit of immune complexes and defects in T lymphocytes and antigen-presenting cells along with a high production of T-helper 2 cytokines. A tolerance-inducible function of nonclassical class Ib human leukocyte antigen (HLA)-G molecule in innate and adaptive cellular responses has been reported, suggesting a role in inflammatory diseases. A 14 bp sequence insertion/deletion polymorphism (rs16375) in the 3'-untranslated region of the HLA-G gene has been associated to the stability of HLA-G messenger RNA. The insertion of the 14 bp sequence seems to be associated with lower levels of soluble HLA-G (sHLA-G). The aim of this study was to evaluate the possible association of the presence of the 14 bp sequence (+14 bp) with SLE. We have HLA-G genotyped 200 SLE patients and 451 healthy control subjects (HS; Italian) and analyzed the plasma levels of sHLA-G and interleukin-10 (IL-10) in a subset of SLE patients and healthy subjects (Italian and Danish). A significant increase of the +14 bp HLA-G allele was detected in the Italian SLE patients compared with HS [P = 0.003, OR 1.44 (95% CI 1.13-1.82)]. A significant increased frequency of HLA-G +14/+14 bp and a decreased frequency of HLA-G -14/-14 bp were observed in SLE patients. There median concentration of sHLA-G was significantly lower in the plasma of SLE patients compared with that in the plasma of healthy controls (P < 0.0001). Furthermore, the results confirmed higher concentrations of IL-10-positive plasma in SLE patients. These results support a potential role for HLA-G in the susceptibility of SLE.     

CD134 expression on CD4+ T cells is associated with nephritis and disease activity in patients with systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is characterized by a deviation of the immune system that involves T cell-dependent autoantibody production. The aim of this study was to investigate the role of co-stimulatory markers on T cells in this disease. Twenty-eight patients with SLE as defined by the American College of Rheumatology (ACR) criteria and 11 healthy controls were included into the study. Eleven patients had biopsy-proven lupus nephritis while 17 patients had no clinical evidence of lupus nephritis. Clinical disease activity was assessed according to the systemic lupus erythematosus disease index (SLEDAI). CD4+ T cell populations in the peripheral blood were analysed for the expression of co-stimulatory markers CD45RO, CD70, CD80, CD86, CD137, CD137L, CD134, CD152, CD154 and ICOS. SLE patients showed an increased frequency of peripheral CD4+ T cells expressing high levels of CD80, CD86 and CD134 compared to healthy controls (7.1 +/- 1.5% versus 1.7 +/- 0.9%; P < 0.005; 2.3 +/- 0.4% versus 1.0 +/- 0.2%; P = 0.008, 20.2 +/- 2.0% versus 10.6 +/- 1.9%; P < 0.005, respectively). Significantly higher levels of CD80 on CD4+ T cells were detected in SLE patients with lupus nephritis compared to patients without nephritis (11.9 +/- 3.3% versus 4.0 +/- 0.7%; P < 0.005). There was an increased presence of CD134+ CD4+ cells in SLE patients with lupus nephritis (27.5 +/- 4.0% versus 15.5 +/- 1.3%; P < 0.005). CD80 and CD134 expression was significantly correlated with SLEDAI (r = 0.42, P = 0.03; r = 0.56, P < 0.005). Co-stimulatory molecules on CD4+ T cells are associated with renal disease and disease activity in patients with systemic lupus erythematosus.     

Hepatitis B antigen and systemic lupus erythematosus

Summary Sera from 22 patients with systemic lupus erythematosus (SLE) were examined for the presence of hepatitis B antigen (HBsAg) by a complement fixation (CF) test, by an immunoelectrophoretic method (counterelectrophoresis-CEP), and by radioimmunoassay (RIA). The sera from 8 patients gave positive results using CF. However, the same sera and sera from 28 additional SLE patients, when tested with CEP and RIA, were not shown to contain HBsAg.Additional studies were carried out in order to characterize the factor responsible for the false positive CF of the 8 SLE sera. It was shown that the sera also fixed complement in presence of normal serum previously submitted to freezing and thawing or heating at 65°C. The complement fixing factor was readily absorbed by aggregated IgG but not by insolubilized HBsAg. Complement fixation was strongly diminished by 2-mercaptoethanol treatment of SLE serum. It thus appears that the false positive reactions for the presence of HBsAg obtained by CF are due to the occurrence of anti-antibodies reacting with aggregated IgG. There is no increased incidence of HBsAg in the serum of SLE patients.This work was supported by the Dubois-Ferrière Dinu Lipatti Foundation and the Swiss National Fund (grant no. SR 3260-0.74).     

Sicca symptoms in Thai patients with rheumatoid arthritis, systemic lupus erythematosus and scleroderma: a comparison with age-matched controls and correlation with disease variables

This study was performed to determine the prevalence of ocular and oral sicca symptoms in Thai patients with rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and scleroderma (Scl). The ocular symptoms and sign (the Schirmer's 1 test) and the oral sicca symptoms and sign (the Saxon's test) in each of 50 RA, SLE and Scl patients were compared with their age-matched controls. The correlation between the presence of sicca symptoms and signs with their clinical activity was also determined. Ocular sicca symptoms were found more common in patients with RA (38% vs 18%, p < 0.05), SLE (36% vs 14%, p < 0.05) and Scl (54% vs 16%, p < 0.01), and oral sicca symptoms were found more common in SLE (22% vs 0%, p < 0.01), and Scl (16% vs 4%, p < 0.05) than their controls. However, only RA patients had a significantly higher proportion of positive Schimer-1 test compared with their controls (p < 0.01). There was no strong correlation between sicca symptoms or signs and other clinical or laboratory variables (age, disease duration, disease activity, disease severity, and antibody to Ro and La antigens) in these three groups. In conclusion, sicca symptoms were seen significantly more common in Thai patients with connective tissue diseases, but the symptoms did not show a good correlation with the clinical and laboratory variables.     

Increased serum levels of soluble L-selectin (CD62L) in patients with active systemic lupus erythematosus (SLE)

The adhesion molecule L-selectin (CD62L) mediates lymphocyte recirculation and leucocyte rolling on vascular endothelium at sites of inflammation. Serum levels of soluble L-selectin (sL-selectin) were measured in patients with SLE in order to relate these levels to clinical activity and immunological parameters. An ELISA was used to detect the soluble form of human L-selectin (CD62L) in 42 patients with SLE and in 33 healthy individuals. The mean +/- s.e.m. values of sL-selectin were 1285 +/- 121 ng/ml for patients with SLE and 986 +/- 180 ng/ml for healthy blood donors, but there was no significant difference. When patients with active SLE were analysed, higher levels of circulating sL-selectin were found when compared with patients without activity (1497 +/- 167 ng/ml versus 941 +/- 150 ng/ml; P = 0.028). We found a significant correlation between the levels of sL-selectin and of dsDNA antibodies (r = 0.36, P = 0. 044) and between levels of sL-selectin and SLE Disease Activity Index (SLEDAI) score (r = 0.42, P = 0.003). Patients with active SLE studied cross-sectionally showed significant elevations of sL-selectin (CD62L) compared with controls. Thus, the levels of this soluble adhesion molecule correlated with active disease and levels of anti-dsDNA antibodies.     

Lung involvement in systemic lupus erythematosus (SLE)--own experience

Pulmonary disorders in systemic lupus erythematosus are frequent and sometimes they are the first symptoms of the disease. SLE may cause a variety of clinical presentations and pathologic patterns, which can be difficult to diagnose. We observed 11 patients (9 women and 2 men) with pulmonary manifestations of SLE during last 18 years in our department. Mean age of patients was 47.7 +/- 13.4 years. There were no patients with drug induced SLE. Interstitial lung diseases (7/11) acute or chronic and pleural involvement (5/11) were the most frequent clinical presentation. In three cases airway disease presented as reduction of FEV1%VC index was detected. In one case "shrinking lung" syndrome was confirmed by muscle function (diaphragm relaxation time) and lung function tests. Pulmonary hypertension confirmed by echocardiography, was associated with interstitial lung disease or vasculitis. Six cases representing different lung involvement pattern of SLE were described in details.     

Elevated levels of soluble CD40 ligand (sCD40L) in serum of patients with systemic autoimmune diseases

The CD40–CD40L costimulatory pathway is involved in the evolution of many autoimmune diseases including systemic lupus erythematosus (SLE), rheumatoid arthritis (RA) and Sjögren's syndrome (SS). Increased levels of sCD40L in the serum have been associated with disease activity in SLE. The aim of this study was to investigate the role of sCD40L in the development of lupus nephritis and examine its possible association with cryoglobulinemia in Sjögren's syndrome. We used a 2-site sandwich ELISA to measure the levels of sCD40L in sera, from 64 patients with SLE, RA and SS and 17 healthy blood donors. Biological specimens from the affected tissues such as urine from patients with lupus nephritis and saliva from patients with SS were also tested. In this regard, paired sera and first morning urine samples from 6 SLE patients (3 with active lupus nephritis and 3 with inactive lupus nephritis) were tested with the sCD40L ELISA protocol as well as paired sera and salivary samples from 5 patients with SS and cryoglobulinemia, 5 patients with SS and anti-Ro or anti-La autoantibodies and 5 age-matched healthy control donors. We also examined possible correlations of sCD40L levels with several laboratory and clinical parameters in SS and SLE. We found that sera from SLE and SS patients had significantly higher levels of sCD40L compared to sera from healthy control donors. No sCD40L was detected, in urine samples of patients with either active or inactive nephritis and in salivary samples from SS patients or normal subjects. Soluble CD40L is elevated in sera of SS and SLE patients but further investigation is needed to determine its possible role in SLE nephritis and Sjögren's syndrome.     

Malignant lymphoma in patients with systemic rheumatic disease (rheumatoid arthritis, systemic lupus erythematosus, systemic sclerosis, and dermatomyositis): a clinicopathologic study of 24 Japanese cases

We conducted clinicopathologic and immunohistochemical analyses of the prevalence of Epstein-Barr virus (EBV) among 24 patients with malignant lymphoma complicating systemic rheumatic diseases. (SRD) These 24 patients included 17 with rheumatoid arthritis (RA), 3 with systemic lupus erythematosus (SLE), 2 with systemic sclerosis (SS), and 2 with dermatomyositis (DM). There were 2 men and 22 women ranging in age from 30 to 86 years (mean: 64 years). The interval between the onset of rheumatic disease and that of malignant lymphomas ranged from 3 months to 35 years (mean: 142 months). The use of immunosuppressive drugs before the onset of malignant lymphoma was recorded in 15 patients. Among them, 5 patients received methotrexate (MTX) therapy. Malignant lymphomas were found at extranodal sites in 9 patients, and the disease was in the advanced stage in 17 patients. Histologic and immunohistochemical studies demonstrated that 18 cases (75%) were B-cell lymphoma (RA=12, SLE=2, SS=2, DM=2), 3 (12.5%) were peripheral T-cell lymphoma (RA=3), and 3 (12.5%) were classical Hodgkin lymphoma (RA=2, SLE=1). As in previous reports, there was an increased frequency of diffuse large B-cell lymphoma (50%) in the present series. Moreover, a majority of the diffuse large B-cell lymphomas exhibited activated B-cell phenotype. EBV-encoded small RNAs (Epstein-Barr early region [EBER]-) and/or LMP-1+tumor cells were identified in only 3 cases of classical Hodgkin lymphomas. Our findings suggested EBV-associated lymphoma comprised only a small fraction of all non-Hodgkin's lymphomas in the general SRD patient population.     

Interplay of immunoglobulin G heavy chain markers (Gm) and HLA in predisposing to systemic lupus nephritis

We have studied the distribution of IgG heavy chain markers (Gm) among 90 Hungarian patients with systemic lupus erythematosus (SLE) (55 of whom were also typed for HLA). This study confirms previously described increases in HLA-B8 and DR3 in this condition. No difference in the distribution of Gm phenotypes was found between patients and 168 controls from the same geographical area. HLA-B8/Gm homozygous individuals were, however, at greater risk for SLE (relative risk = 5.13) compared to B8 + Gm heterozygotes or B8- individuals, irrespective of Gm phenotype. When patients with renal manifestation (n = 40) were compared to those without, the Gm phenotype 3; 5, 13 was found to be significantly increased (chi 2 = 10.36, P less than 0.0001, relative risk (RR) = 4.69). HLA and Gm increased additively the risk for renal manifestations in that for those patients who were both Gm3;5,13+ and HLA-B8+, PR was 110, while it was 21.2 for Gm3;5, 13-/B8+, 7.9 for Gm3;5, 13+/B8- and 1.0 for Gm3;5, 13-/B8- patients. The study suggests that combined HLA and Gm typing can be used to identify SLE patients at high risk for manifesting renal abnormalities.     

Bronchoalveolar lavage cell analysis and lung function impairment in patients with systemic lupus erythematosus (SLE).

We examined the relationship between peripheral blood and bronchoalveolar lavage (BAL) lymphocyte phenotypes and lung function in 19 patients with SLE, and evaluated their association with disease activity. Lung function assessment showed a mildly restrictive pattern with frequent impairment of transfer factor for carbon monoxide (T1,co) and diffusing capacity of the alveolocapillary membrane (Dm), of late-expiratory airflow rates and with a high prevalence of increased airway resistance. T1,co, Kco and Dm correlated inversely with the numbers of CD8+ cells and CD56+/CD16+/CD3- (NK) cells in BAL. Oxygen radical production, both by stimulated and unstimulated BAL cells and blood polymorphonuclear leucocytes (PMN) was significantly increased in SLE. In comparison with healthy controls, patients with SLE had a lower percentage of CD19+ B cells in the BAL versus an increased percentage of these cells in peripheral blood. HLA-DR expression on CD4+ and CD8+ lung lymphocytes was markedly increased in SLE. Current SLE disease activity was not associated with changes in BAL or peripheral blood lymphocyte phenotypes. Our data suggest that an ongoing cell-mediated immune response is present in the lungs in SLE, particularly involving activated CD8+ T cells and CD56+/CD16+/CD3- NK cells. It is associated with up-regulated local production of oxygen radicals and with impaired pulmonary diffusing capacity. This inflammatory process seems to be independent of general SLE disease activity.     

Proximal interleukin-10 gene polymorphisms in Italian patients with systemic sclerosis

Interleukin-10 (IL-10) can favour the development of fibrosis by promoting a relative shift towards T helper 2 responses. Three single base pair substitutions in the 5' flanking region of the IL-10 gene (G/A -1082, C/T -819 and C/A -592) influence the amount of IL-10 secreted in cell cultures: the GCC haplotype is associated with an increased production, while the ACC and the ATA haplotypes are associated with intermediate and decreased production. Accordingly, three phenotypes have been individuated: high producers (GCC+/GCC+), medium producers (GCC+/GCC-) and low producers (GCC-/GCC-). We hypothesised that IL-10 haplotypes and genotypes are differently expressed in patients with systemic sclerosis (SSc) with the limited cutaneous SSc (lcSSc) subset or the diffuse cutaneous SSc (dcSSc) subset. One hundred and sixty-one unrelated Italian patients with SSc and 94 controls have been included. Their DNA was extracted and stored before being analysed by polymerase chain reaction with sequence-specific primers. The GCC haplotype is overrepresented in patients with SSc; subjects with dcSSc were the primary contributors to these results (dcSSc: 52.2% vs controls: 37.2%; chi2= 8.519, 2 d.f., corrected P= 0.04). In Scl70-positive patients, the GCC haplotype increased the likelihood of presenting the dcSSc subset [chi2= 12.56, P < 0.0005; odds ratio (OR) = 3.89, 95% confidence interval (CI(95)) = 1.69-9.08]; these results were confirmed at the phenotypic level (chi2= 11.67, 2 d.f., P= 0.003). In Scl70-positive patients, the high-producing phenotype was associated with poor survival, independently from disease subset and gender (hazard ratio = 9.9, CI(95)= 1.6-61.27, P < 0.05). The IL-10 haplotype and genotype associated with high IL-10 production may alter the susceptibility to SSc and/or its expression, increasing the prognostic value of other well-known markers of disease severity.     

Increased expression of membrane TNF-alpha on activated peripheral CD8+ T cells in systemic lupus erythematosus

Membrane TNF-alpha is a precursor form of soluble TNF-alpha and exerts pro-inflammatory functions in a cell-to-cell contact manner. We showed that membrane TNF-alpha is induced upon activation on the cell surface of CD4+ T cells and CD8+ T cells. In patients with systemic lupus erythematosus (SLE), the percentage of membrane TNF-alpha-bearing CD8+ T cells (41.5+/-12.3%) was significantly higher compared with those of healthy controls (26.7+/-3.9%) (p=0.007) or patients with rheumatoid arthritis (29.8+/-15.4%) (p=0.038). Membrane TNF-alpha-bearing CD8+ T cells from SLE patients displayed cytotoxic activity against L929 cells. It is possible that membrane TNF-alpha may be involved in the increased apoptosis and the generation of autoantigens in SLE.     

Decreased CD4+CD25+ T cells in peripheral blood of patients with systemic lupus erythematosus

Recent animal studies have shown that CD4+CD25+ T cells play a crucial role in the suppression of the immune response and that depletion of this subset of T cells might lead to development of autoimmune diseases. The aim of the present study was to investigate the levels of CD4+CD25+ T cells in the peripheral blood of patients with systemic lupus erythematosus (SLE). Ninety-four SLE patients, 52 patients with rheumatoid arthritis (RA) and 50 age- and gender-matched healthy individuals were enrolled in the study. A flowcytometric method was applied in the measurement of CD4+CD25+ T cells. The results showed that patients with SLE had statistically lower levels of CD4+CD25+ T cells than did normal controls, when expressed as either percentages of peripheral blood mononuclear cells (PBMCs) (mean +/- SD, 8.49 +/- 6.36 versus 11.11 +/- 4.58%, P < 0.05) or absolute cell numbers (98.77 +/- 97.52 versus 213.93 +/- 104.52 cells/mm3, P < 0.05). In terms of CD25brightCD4+ T cells, defined as having a fluorescence intensity of CD25 expression exceeding 100, SLE patients still had significantly lower levels than did normal controls expressed as percentages of PBMCs (1.76 +/- 1.32 versus 3.73 +/- 1.30%, P < 0.05). No significant differences could be found between RA patients and normal controls. The overwhelming majority of CD4+CD25+ T cells belonged to CD45RO+ cells and most did not express the CD69 molecule. Although decreased CD4+CD25+ T cells were found in SLE patients, we failed to find a significant correlation between the levels of CD4+CD25+ T cells and disease activities of SLE. To the best of our knowledge, this is the first study to demonstrate that patients with SLE had decreased CD4+CD25+ T cells. However, the exact role of the decreased CD4+CD25+ T cells in the pathogenesis of SLE remains to be elucidated.     

HLA-DP-positive T cells in patients with systemic lupus erythematosus

HLA-DP+ T cells in peripheral blood from 23 patients with systemic lupus erythematosus (SLE) were examined using two-colour flow cytometry analysis. A marked increase of HLA-DP+ T cells was observed in patients with SLE (20.5-98.7%; 59.8 +/- 20.8%) in comparison to normal subjects (1.3-20.6%; 11.1 +/- 7.2%), and the ratio of these cells greatly exceeded that of the HLA-DR+ T cells (6.5-49.1%; 21.5 +/- 12.7%). This high frequency of HLA-DP+ T cells in patients with active SLE decreased with prednisolone therapy. When the lymphocytes from normal subjects were stimulated with PHA in vitro, HLA-DP+ T cells increased from 1.8 to 59.2%. Therefore, it appears that the HLA-DP antigen expression on T cells is a practical marker for monitoring changes in the proportion of activated T cells in patients with SLE during the course of therapy.     

Bone mineral density and vitamin D status in systemic lupus erythematosus (SLE): A systematic review

Despite the improvement in the quality of life of patients with SLE due to scientific and technological advances, SLE remains a disease that over the years may produce irreversible damage to patients. Osteoporosis and secondary bone fractures are two of the major causes of irreparable injury in patients with SLE. Vitamin D insufficiency may play a vital role both in reduced bone mineral density (BMD) and in the appearance of fractures, although its mechanisms of action are still unclear. We performed a systematic review of the literature in order to determine the prevalence and predictors of reduced vitamin D plasma levels, bone loss and the presence of fractures in SLE patients. Our review encompassed all English-language publications using Medline and EMBase electronic databases from their inception (1966 and 1980, respectively) to December 2016. We included all intervention studies and observational studies in which vitamin D plasma levels, BMD and bone loss were measured and applied to patients with SLE. Previous studies suggested an increase in bone loss and fracture in patients with SLE compared with general population and although there is a high prevalence of vitamin D insufficiency in the general population, previous studies had demonstrated lower vitamin D levels in patients with SLE compared to age-matched controls. The etiology of reduced bone mass and reduced vitamin D plasma levels in SLE is multifactorial and includes a variety of intrinsic factors related to the disease itself and treatment side effects. SLE patients are at risk for developing these two comorbidities (reduced vitamin D plasma levels and low BMD) and it is therefore essential to study, monitor, prevent and treat bone metabolism disorders in SLE patients.     

Release of platelet-activating factor in systemic lupus erythematosus

The biologically active 1-O-alkyl-2-acetyl-sn-glyceryl-3-phosphorylcholine (platelet-activating factor; PAF) is inactivated in plasma mainly by a specific PAF acetylhydrolase (1-alkyl-2-acetyl-sn-glyceryl-3-phosphorylcholine acetylhydrolase; EC 3.1.1.48). In the present study, PAF was released in detectable amounts (5.4 +/- 2.9 ng/ml; mean +/- 1 SD) in the plasma of 8 out of 10 patients with systemic lupus erythematosus (SLE) during the most active phases of the disease. PAF was never detectable in the plasma of patients with inactive SLE or of healthy subjects. PAF acetylhydrolase activity was markedly reduced in sera of 10 patients with active SLE as compared to 7 patients with inactive SLE, 16 patients with rheumatoid arthritis (RA), 5 patients with nephrotic syndrome (NS) and 15 healthy subjects. A kinetic study of the enzyme in patients with active SLE suggested an overall reduced activity rather than an intrinsic defect of the enzyme. PAF acetylhydrolase in sera of patients with active SLE shared with that of healthy subjects the same substrate specificity, sensitivity to enzymatic and chemicophysical treatments and association to low-density lipoprotein (LDL), acting as carrier of PAF acetylhydrolase in plasma. However, the protein concentration of LDL was significantly reduced in patients with active SLE as compared to patients with inactive SLE, RA and NS and to healthy subjects, thereby suggesting that the reduction of PAF acetylhydrolase activity in active SLE might be due at least in part to a carrier defect related to the activity of the disease. In addition, experiments in which serum of patients with active SLE and serum of healthy subjects were mixed in different combinations indicated the absence of factors inhibiting PAF acetylhydrolase activity in SLE patients.     

Opsonization by anti-dsDNA antibodies of apoptotic cells in systemic lupus erythematosus

In order to asses the role of the soluble mediators of serum from patients with SLE in the apoptotic cell clearance, we measured the in vitro phagocytosis of apoptotic Jurkat cells by normal healthy donor macrophages in the presence of SLE patients' sera. A significant increase of the phagocytic index (NHD = 1.0 +/- 0.3; SLE = 1.9 +/- 0.6; p < 0.01) was to be observed in the presence of serum from patients with SLE. The increased phagocytic index correlated to the anti-dsDNA antibodies titers. We conclude that anti-dsDNA antibodies present in sera of patients with SLE favor the apoptotic cell phagocytosis by opsonization of the target cells. This may represent a deviation of the clearance process towards inflammation and a new pathologic feature of these autoantibodies in SLE.