Successful long-term systemic sclerosis treatment by high-frequent low-dose B cell-depleting therapy.

OBJECTIVES: Systemic sclerosis (SSc) is a multiorgan disease with a 10-year mortality rate of up to 50 %. B cell-depleting therapy with rituximab (RTX) appears effective in SSc treatment, but data from randomized controlled trials (RCTs) are lacking, and the frequency and dosage of RTX in SSc have no consensus. We aimed to evaluate the long-term efficacy and safety of quarterly RTX administration in SSc. METHODS: This study retrospectively analyzed 40 patients with SSC treated with RTX twice within 14 days every 3 months from 2010 to 2020. The patients fulfilled the LeRoy and the American College of Rheumatology/European League Against Rheumatism Criteria for SSc. Modified Rodnan skin score (mRSS), lung function test results, and serum immunoglobulin (IgG, IgA, and IgM) concentrations were analyzed. RESULTS: A total of 40 patients with SSc received RTX over a median time of 3.9 years (range: 1-10 years). The median mRSS (baseline: 19, 24 months: 16, p < 0.001) demonstrated a significant improvement, and the predicted forced vital capacity was stable. No new or unexpected safety signals, especially regarding treatment-related infectious adverse events, were observed. Immunoglobulin concentrations were within normal range, and specific antibodies to pneumococcal polysaccharides were preserved despite long-term B cell-depleting therapy. None of the patients died during the observation period of up to 10 years. CONCLUSION: SSc was effectively and safely treated with low-dose RTX quarterly. RCTs are warranted to validate the advantage of continuous B cell depletion by quarterly low-dose RTX administration compared to other treatment intervals.

[Common German language nomenclature for systemic sclerosis]. / Gemeinsame deutschsprachige Nomenklatur für die systemische Sklerose.

Large data bases and the projects arising from them have led to a much improved understanding of systemic sclerosis over the last decade. Serology has developed further so that more autoantibodies are available for routine testing. Capillary microscopy has become standard and relevant progress has also been made in therapy. Many diagnostic terms found in medical documentation do not adequately reflect this progress. The nomenclature is inconsistent and, therefore, confusing. The international classification of diseases (ICD) nomenclature is, from our point of view, also in need of improvement. This article aims to reestablish a common German language standard for systemic sclerosis, which reflects current knowledge and is suitable for implementation in the clinical routine.

Ultrasound screening for interstitial lung disease in rheumatoid arthritis.

OBJECTIVES: As interstitial lung disease (ILD) in rheumatoid arthritis (RA) patients is associated with increased mortality due to loss of diffusion capacity and pulmonary hypertension, regular screening for structural abnormalities of the lung is advised. In addition to standard radiological examination with computed x-ray tomography, ultrasound of the lung could allow non-invasive and radiation-free structural monitoring of the lung. The objective of this study was to test the frequency of abnormalities in lung sonography in patients with RA who did not have clinical signs or symptoms of lung disease. METHODS: In a prospective study of 64 consecutive patients with rheumatoid arthritis and 40 healthy volunteers, we screened the pleura and the pulmonary parenchyma for sonographic abnormalities. All RA patients underwent high resolution computer tomography of the lung. RESULTS: 28% of RA patients showed pleural nodules or B-line phenomena. In these patients, CT scans showed signs of incipient interstitial lung disease. Lung sonography showed sporadic abnormalities in 7% of the healthy controls. CONCLUSIONS: Transthoracic ultrasound of the lung is an inexpensive and safe tool to screen patients with RA for incipient pulmonary structural changes.

The kappa-deleting element. Germline and rearranged, duplicated and dispersed forms.

Human light chain genes are used in a kappa before lambda order. Accompanying this hierarchy is the rearrangement of a kappa-deleting element (Kde) which eliminates the kappa locus before lambda gene rearrangement. In approximately 60% of rearrangements the Kde recombines at a conserved heptamer within the J kappa-C kappa intron. We demonstrated that aberrant V/J rearrangements possessing apparent "N" nucleotides existed 5' to the J kappa-Kde rearrangements. This suggests that the Kde may selectively eliminate nonfunctional V/J alleles. A kappa-producing cell that displayed the unusual finding of lambda gene rearrangement demonstrated a rearranged Kde. This rearrangement was a V kappa/Kde recombination and the heptamer-11 bp spacer-nonamer flanking the V kappa is the target site of the Kde 40% of the time. The mouse possesses a counterpart to the Kde (recombining sequence [RS]) and the highly conserved regions surround the heptamer-spacer-nonamer signals. No complete protein product was predicted from the germline Kde near its break-point and no consistent fusion product was predicted from either the V/Kde or V/J-Kde rearrangements. A distal portion of the Kde is duplicated and is present at 2q11 as well as 2p11. The evolutionary conservation of the kappa-elimination event, the duplication and maintenance of the Kde indicates that it has a function. A portion of the Kde may still prove to encode a trans-acting factor that directly affects lambda rearrangement. A certain role for the Kde is its site-specific rearrangement, which destroys ineffective kappa genes and sets the stage for lambda gene utilization.

Superior specificity of anti-citrullinated peptide antibodies in patients with chronic lymphocytic leukemia and arthritis.

OBJECTIVES: Sera from patients with lymphoid neoplasias contain rheumatoid factors (RF) so often that RF are of limited use for diagnosing arthritis in lymphoma patients. Antibodies against citrullinated peptides (ACPA) might be helpful in distinguishing between true RA and rheumatoid factor-positive conditions with arthritis. We compared the specificity of RF and of ACPA for the diagnosis of RA in patients with B-cell chronic lymphocytic leukemia (CLL). METHODS: One hundred and seven patients with CLL without any clinical signs of arthritis and five patients with RA and concomitant CLL were included in the investigation. Serum samples were tested for RF-isotypes IgM, IgG and IgA. ACPA were determined with an ELISA that detects anti-cyclic citrullinated peptide (aCCP) antibodies. RESULTS: RF well beyond the cut-off levels were detected in 50% of the CLL patients without RA. The isotype distribution was 41% IgM-RF, 20% IgG-RF and 3% IgA-RF. None of the 107 CLL patients without arthritis had Accp antibodies. Within the whole cohort of CLL patients the specificity for the diagnosis of RA was 100% for aCCP antibodies and 59% for IgM-RF. CONCLUSIONS: Only aCCP antibodies but not IgM-, IgG- or IgA-RF are useful for the diagnosis of RA in patients with CLL.

IL10R1 loss-of-function alleles in rheumatoid arthritis and systemic lupus erythematosus.

OBJECTIVE: IL-10 is a pleiotropic cytokine involved in the regulation of innate and cell-mediated immunity and a key mediator within the disturbed SLE immune system. IL-10 binds to IL10R1, which is expressed on a variety of immune cells and activates the JAK-STAT pathway. Two (out of several known) genetic IL10R1 variants may alter IL-10 binding or signal transduction. Here we investigate the differential activity of these IL10R1 variants and their possible association with RA or SLE susceptibility. METHODS: IL10R1-wt, IL10R1-S138G, IL10R1-G330R, or IL10R1- S138G +G330R were cloned into pIRESpuro3 and transfected into HeLa cells. Single cell clones were tested for IL-10-induced SOCS3- and SLAM gene expression by real-time PCR. DNA from 182 RA patients, 222 SLE patients, and 250 healthy controls was genotyped by allele-specific PCR. RESULTS: A biphasic increase of SOCS3 mRNA was observed that peaked at 15 minutes and 4 hours after IL-10 stimulation. The presence of IL10R1 S138G and G330R showed a weaker induction of both SOCS3 and SLAM upon stimulation with IL-10. In RA a homozygous G330R genotype was more commonly present than in controls (15.4% vs. 7.6%; p<0.05). In SLE the G330R allele frequency was also increased (36.3% vs. 30.0%; p<0.05) without showing a gene-dose relationship at the genotype level. CONCLUSIONS: Based on these results, both variants of the IL10R1 gene are loss-of-function alleles. IL10R1 G330R may possibly contribute to RA or SLE disease susceptibility in Caucasian populations.

Expression of Bcl-2 and Bcl-2-Ig fusion transcripts in normal and neoplastic cells.

We examined the expression of the Bcl-2 gene at chromosome segment 18q21, that is translocated into the Ig heavy chain gene locus in t(14;18) bearing lymphomas. Bcl-2, while B cell associated, is expressed in a variety of hematopoietic lineages including T cells. Bcl-2 mRNA levels are high during pre-B cell development, the time at which the t(14;18) translocation occurs, but are down regulated with maturation. Like certain other oncogenes, Bcl-2 is quiescent in resting B cells but up-regulated with B cell activation. Mature B cell lymphomas with a t(14;18) have log-folds more mRNA than matched counterparts without the translocation. A sensitive S1 protection assay revealed that all transcripts in t(14;18) B cells were Bcl-2-Ig fusion mRNAs and originated from the translocated allele. Thus, there is a marked deregulation of Bcl-2 when it is introduced into the Ig locus in t(14;18) lymphomas.

Cytokine regulation of apoptosis and Bcl-2 expression in lymphocytes of patients with systemic lupus erythematosus.

Both faulty regulation of apoptosis and the inappropriate expression of several interleukins have been considered important defects of lymphocytes in the human autoimmune disease systemic lupus erythematosus (SLE). We therefore tested the in vitro effect of recombinant interleukin (IL-)-2, 4, 7, and 15 on peripheral blood mononuclear cells from patients with SLE and from healthy volunteers. Intracellular Bcl-2 and Bax expression was measured by fluorocytometry and the rate of apoptosis was determined by the TUNEL technique and propidium iodide staining. IL-2, IL-4, IL-7 and IL-15 led to a significant increase in Bcl-2 and a reduction in cell death rates, which was even more pronounced in SLE. Bax levels remained unchanged. Interestingly, the high ex vivo Bcl-2 content of lymphocytes from some SLE patients was maintained after growth factor withdrawal. Anti-apoptotic cytokine signaling may significantly influence the deregulation of cell death in SLE lymphocytes.

Increased levels of circulating intercellular adhesion molecule-1 in patients with systemic sclerosis.

OBJECTIVE: To determine the value of the circulating intercellular adhesion molecule (cICAM-1) as a marker for the inflammatory and fibrotic processes in systemic sclerosis (SSc). METHODS: We determined serum levels of cICAM-1 and of the soluble interleukin-2 receptor (sIL-2R) by an enzyme-linked immunosorbent assay in 33 patients with SSc. These values were compared to the concentrations of acute phase reactants and to the extent of skin involvement in diffuse and limited scleroderma. RESULTS: cICAM-1 was elevated in patients with diffuse SSc (498 +/- 134 ng/ml) as compared with 82 healthy controls (312 +/- 71 ng/ml) (mean +/- SD, p < 0.0001). The elevation of cICAM-1 did not correlate with the duration of disease, the pattern of organ manifestations or the type of treatment. While the concentrations of acute phase proteins were not elevated in SSc, a significant correlation between increased serum sIL-2R and cICAM-1 was observed. CONCLUSION: Increased levels of cICAM-1 indicate an activation of immune processes in SSc. The clinical value of the cICAM-1 determination in SSc can only be judged in longitudinal studies.

Interstitial nephritis in patients with systemic lupus erythematosus: a manifestation of concomitant Sjögren's syndrome?

In order to estimate the frequency of functionally relevant tubular damage in SLE patients we used the presence of overt renal tubular acidosis as an indicative parameter of interstitio-tubular damage in a cohort of 109 SLE patients who were well characterized for potential Sjögren's syndrome. Only two patients had overt renal tubular acidosis and interstitial nephritis without major glomerular involvement. Both patients, aside from having systemic lupus erythematosus, had a number of clinical features of concomitant primary Sjögren's syndrome. Based on the results obtained and the analyses of previously published cases, we put forward the hypothesis of simultaneous primary Sjögren's syndrome as the prevailing associative factor for the rare occurrence of isolated interstitial nephritis in SLE.

Transcriptional overexpression of the proto-oncogene bcl-2 in patients with systemic Lupus erythematosus.

In systemic Lupus erythematosus (SLE) spontaneous hyperreactivity of the cells of the immune system leads to the production of pathogenic autoantibodies. A hyperproliferative state of lymphocytes is indicated by the increased expression of nuclear oncogenes. We investigated the expression of a putative proto-oncogene, bcl-2, which is responsible for prolonged survival of lymphocytes and protection from programmed cell death. In 19 of 24 patients with SLE an increased concentration of bcl-2 mRNA was found in unstimulated circulating blood lymphocytes. The overexpression of the bcl-2 gene was more pronounced in patients with active SLE. A pathogenic role of increased bcl-2 expression and prolonged survival of autoimmune memory cells in SLE can be hypothesized.

Spingosine-1-phosphate stimulates proliferation and counteracts interleukin-1 induced nitric oxide formation in articular chondrocytes.

OBJECTIVE: Sphingosine-1-phosphate (S1P) is a messenger molecule, with important functions in inflammation and wound healing. The present study was performed to elucidate a possible role of S1P signaling in articular chondrocytes. METHODS: Human and bovine primary chondrocytes were cultured in monolayer. Reverse transcriptase polymerase chain reaction (RT-PCR) was performed to detect S1P receptor mRNA. Proliferation of S1P stimulated chondrocytes was measured by 3H-thymidine uptake. Supernatants of cultured bovine chondrocytes stimulated with S1P alone or in combination with interleukin-1beta (IL-1beta) were tested for nitric oxide (NO) formation and expression of inducible nitric oxide synthase (iNOS). Matrixmetalloprotease-13 (MMP-13) and aggrecanase-1 (ADAMTS-4) were evaluated using real-time PCR. Glycosaminoglycan (GAG) loss from bovine cartilage explants was evaluated using the dimethylene blue method. RESULTS: S1P1, S1P2 and S1P3 but not S1P4 and S1P5 receptor mRNA were detected in human and bovine chondrocytes. S1P dose dependently induced proliferation in bovine and human chondrocytes. S1P significantly reduced NO formation and iNOS mRNA and protein expression, both in un-stimulated and IL-1beta stimulated bovine chondrocytes. Furthermore, S1P dose dependently inhibited IL-1beta induced expression of ADAMTS-4 and MMP-13 and diminished IL-1beta mediated GAG depletion from cartilage explants. CONCLUSION: These results suggest that S1P provides an anti-catabolic signal in articular chondrocytes.

Effect of pulsed electromagnetic fields on proteoglycan biosynthesis of articular cartilage is age dependent.

OBJECTIVE: To investigate the effects of a pulsed electromagnetic field (EMF) on articular cartilage matrix biosynthesis with regard to age and cartilage damage using a matrix depleted cartilage explant model. METHODS: Cartilage explants were obtained from metacarpophalangeal joints of calves and adult cows. After depletion of the extracellular matrix by trypsin digestion, samples were maintained in serum-free basal medium with and without the addition of interleukin 1beta (IL1beta). Half the samples were subjected to an EMF for 24 minutes daily; the other half were left untreated. Undigested and untreated explants served as negative controls. After 7 days, biosynthesis of matrix macromolecules was assessed by [35S]sulphate incorporation and values were normalised to hydroxyproline content. RESULTS: The EMF increased matrix macromolecule synthesis in undigested, untreated explants (p<0.009). In matrix depleted samples the EMF had no stimulatory effect on proteoglycan biosynthesis. IL1beta significantly decreased the de novo synthesis of matrix macromolecules (p<0.00004) in young and adult samples, but an EMF partly counteracted this inhibitory effect in cartilage samples from young, but not old animals. CONCLUSION: EMF promoted matrix macromolecule biosynthesis in intact tissue explants but had no stimulatory effect on damaged articular cartilage. The supressive effects of IL1beta were partially counteracted by EMF exposure, exclusively in cartilage derived from young animals. An EMF has age dependent chondroprotective but not structure modifying properties when cartilage integrity is compromised.