Johann O. Schröder

IL-1RA in refractory systemic lupus erythematosus.

There is evidence from animal and human studies that IL-1 might play an important role in the development and maintainence of inflammation in systemic lupus erythemathosus (SLE). We hypothesized that, in SLE, there might be a relative deficiency in the physiologic antagonist of IL-1, IL-1 receptor antagonist (IL-1RA). We therefore treated three patients with active SLE in whom conventional therapy has failed with the human IL-1RA, Anakinra. In two of the three patients there was a transient effect on muscle pain and/or polyarthritis. In one patient with lupus myositis there was no effect at all. The therapy was well tolerated and the only significant side effect was a transient drop in complement levels (C3 and C4) without clinical or laboratory signs of increased SLE activity in all three patients.

Primary antiphospholipid antibody syndrome and retinal occlusive vasculopathy.

PURPOSE To report a 31-year-old healthy patient with retinal venous occlusion in his left eye attributable to primary antiphospholipid antibody syndrome. METHODS The patient was examined clinically. Multiple serologic and clinical investigations were performed to determine the causative disease. He was closely followed up for more than 3 years. RESULTS The presence of lupus anticoagulant in our patient was indicated by a kaolin clotting time index of 27 (normal, <17) and confirmed by the demonstration of IgG antibodies against phospholipids. After long-term oral anticoagulant treatment for 2 years, lupus anticoagulant levels returned to normal, and therapy was stopped. No further thrombotic event occurred during follow-up. CONCLUSIONS In retinal vascular occlusions of unexplained origin, antiphospholipid antibodies may play an important role in the pathogenesis. Detecting these antibodies in the serum of patients with retinal vascular occlusion helps determine the appropriate treatment with long-term oral anticoagulants.

Early interleukin-10 treatment improves survival and enhances immune function only in males after hemorrhage and subsequent sepsis.

Recent studies have demonstrated gender differences in the immune response following hemorrhagic shock with an enhanced immune function and lower mortality following subsequent sepsis in females. Early interleukin-10 (IL-10) treatment has been shown to have beneficial effects on the depressed immune function in males, but not in females following shock. However, it remains unclear if the observed gender-related effect of IL-10 treatment results in an advantage following subsequent polymicrobial sepsis. To study this, male and female CBA/J mice (age 2–3 months) were subjected to hemorrhage (35 ± 5 mmHg for 90 min and fluid resuscitation). At resuscitation, each received either 10 &mgr;g of recombinant murine IL-10 or placebo i.p.. At 48 h after resuscitation, either peritoneal macrophages (pM&phis;) and plasma were harvested, or polymicrobial sepsis was induced by cecal ligation and puncture (CLP). Following CLP, either survival over 10 days was measured, or pM&phis; and plasma were harvested 4 h after CLP to assess TNF-&agr;, IL-6, IL-10, and prostaglandin E2 (PGE2) release of pM&phis; and plasma levels of IL-10, free testosteron, and 17-&bgr; estradiol. Early IL-10 treatment restored depressed proinflammatory immune response in males (TNF-&agr; and PGE2), which was associated with an enhanced survival (P < 0.05) following subsequent sepsis as compared with placebo-treated mice (8/20 and 1/20, respectively). In contrast, the immune response and survival in females receiving IL-10 was not significantly changed, although females treated with IL-10 had a trend towards higher mortality (7/15 and 2/15, respectively;P = 0.08). Thus, early IL-10 anti-inflammatory treatment following hemorrhage has potential beneficial effects only in males associated with enhanced survival following subsequent sepsis.

IL-6 blockade by monoclonal antibodies inhibits apolipoprotein (a) expression and lipoprotein (a) synthesis in humans

Lipoprotein (a) [Lp(a)] is a highly atherogenic lipid particle. Although earlier reports suggested that Lp(a) levels are mostly determined by genetic factors, several recent studies have revealed that Lp(a) induction is also caused by chronic inflammation. Therefore, we aimed to examine whether cytokine blockade by monoclonal antibodies may inhibit Lp(a) metabolism. We found that interleukin 6 (IL-6) blockade by tocilizumab (TCZ) reduced Lp(a) while TNF-α-inhibition by adalimumab in humans had no effect. The specificity of IL-6 in regulating Lp(a) was further demonstrated by serological measurements of human subjects (n = 1,153) revealing that Lp(a) levels are increased in individuals with elevated serum IL-6. Transcriptomic analysis of human liver biopsies (n = 57) revealed typical IL-6 response genes being correlated with the LPA gene expression in vivo. On a molecular level, we found that TCZ inhibited IL-6-induced LPA mRNA and protein expression in human hepatocytes. Furthermore, examination of IL-6-responsive signal transducer and activator of transcription 3 binding sites within the LPA promoter by reporter gene assays, promoter deletion experiments, and electrophoretic mobility shift assay analysis showed that the Lp(a)-lowering effect of TCZ is specifically mediated via a responsive element at −46 to −40. Therefore, IL-6 blockade might be a potential therapeutic option to treat elevated Lp(a) serum concentrations in humans and might be a noninvasive alternative to lipid apheresis in the future.

Interleukin-6 and Tumour Necrosis Factor-α differentially regulate lincRNA transcripts in cells of the innate immune system in vivo in human subjects with rheumatoid arthritis

lincRNAs recently have been discovered as evolutionary conserved transcripts of non-coding DNA sequences and have been implicated in the regulation of cellular differentiation. In humans, molecular studies have suggested a functional role for lincRNAs in cancer development. The aim of the present study was to examine whether these novel molecules are specifically regulated by different cytokines in cells of the innate immune system in humans in vivo and whether lincRNAs thereby might be involved in the pathophysiology of rheumatoid arthritis (RA). Therefore, CD14(+) monocytes were isolated from RA patients before and after anti-IL-6R (tocilizumab) or anti-TNF-α (adalimumab) therapy and lincRNA transcription was analysed by a microarray based experiment. As expected, we found lincRNAs to be present in CD14(+) monocytes of RA patients. However, of the total number of 7.419 lincRNAs examined in this study only a very small number was significantly regulated by either IL-6 or TNF-α (85 lincRNAs, corresponding to 1.1%). The numbers of lincRNAs regulated was higher due to TNF-α compared to IL-6. Interestingly, none of the identified lincRNAs was influenced by both, IL-6 and TNF-α, suggesting the regulation of lincRNA transcription to be highly specific for distinct cytokines. Taken together, our results suggest (1) that lincRNAs are novel intracellular molecular effectors of specific cytokines in cells of the innate immune system in humans in vivo and (2) that lincRNAs might be involved in the molecular pathophysiology of RA.

Gender-related therapy: early IL-10 administration after hemorrhage restores immune function in males but not in females.

Recent experimental studies have found gender differences in the immune response after hemorrhagic shock with an enhanced immune function and lower mortality after subsequent sepsis in females than in males. Interleukin-10 (IL-10) has been shown to play a potential role in the treatment of early proinflammatory state after hemorrhagic shock. Although studies showed beneficial effects of the treatment with IL-10, it remains unclear whether the effects are gender related. To study this, male and female CBA/J mice were subjected to hemorrhage (35+/-5 mmHg for 90 min and fluid resuscitation) or sham operation. At resuscitation, each received either recombinant murine IL-10 (rmIL-10) or placebo i.p. At 48 h after resuscitation, peritoneal macrophages (pMphi) and splenocytes were harvested. IL-1beta and IL-12 release by pMphi and splenocyte proliferation and splenocyte IL-2 and interferon (IFN)-gamma release capacity were assessed. Interleukin-10 plasma levels were not increased after rmIL-10 treatment. The results indicate that rmIL-10 treatment restores depressed immune response (splenocyte proliferation, IFN-gamma, IL-1beta in males after hemorrhagic shock. In contrast, the immune responses after shock in females were not influenced by rmIL-10, with the exception of depressed splenocyte proliferation. In addition, sham-operated male mice treated with rmIL-10 showed immune depression compared with the placebo group. Thus, administration of rmIL-10 during resuscitation after hemorrhage produces salutary effects on the depressed immune responses in males but did not further enhance the immune functions in females under those conditions.

Biologics as treatment for systemic lupus: great efforts, sobering results, new challenges.

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by specific organ manifestations and the production of autoantibodies to nuclear antigens. SLE can induce severe organ damage and carries the risk of fatal outcome. During recent years, no major progress has been made regarding new treatment options except for the introduction of mycophenolate mofetil. Therefore, the results of several large clinical trials using biological agents for treatment of SLE were hopefully awaited. Yet, the application of abatacept, belimumab and rituximab, respectively, to non-renal or renal lupus patients surprisingly has not been successful. Other studies using different agents have not been completed yet. Nevertheless, the results available so far will have a significant impact on the design of future clinical trials and will stimulate the debate on new targets for treatment of SLE.

Successful application of belimumab in two patients with systemic lupus erythematosus experiencing a flare during tocilizumab treatment

This case report describes two female lupus patients who both received biological treatment with tocilizumab and with belimumab. The disease course was remarkably similar in both cases. Tocilizumab resulted in a transient improvement in pleurisy and arthritis but was then followed by a clinical flare accompanied by an increase in autoantibodies and a drop in complement levels. Alike, both patients experienced a rapid and sustained improvement after institution of belimumab. The clinical benefit obtained is currently stable under ongoing belimumab therapy.

C1qRP (CD93) expression on peripheral blood monocytes in patients with systemic lupus erythematosus

Aim of the study was to compare the expression of monocytes C1qRp (CD93) in patients with systemic lupus erythematosus (SLE) with that of healthy controls and to determine the influence of glucocorticoids and LPS on C1qRp expression. Thirty-six SLE patients and 20 healthy controls were analyzed by flow cytometry. Additionally, monocytes from five patients and five controls were cultured and stimulated with dexamethasone, interferon-γ and LPS, respectively, before the measurement of C1qRp expression. There was no difference in C1qRp expression between SLE and HC. SLE patients with no or only low dose steroids had a significantly higher C1qRp expression than those with higher doses. However, in vitro dexamethasone did not stimulate or down-regulate C1qRp expression. Upon LPS stimulation, C1qRp was significantly up regulated on monocytes both from patients and from controls. In conclusion, C1qRp expression and regulation was not altered in SLE patients. Possible relations with disease activity and medication need further investigations.

B Lymphocyte Stimulator (BLyS) Is Expressed in Human Adipocytes In Vivo and Is Related to Obesity but Not to Insulin Resistance

Inflammation and metabolism have been shown to be evolutionary linked and increasing evidence exists that pro-inflammatory factors are involved in the pathogenesis of obesity and type 2 diabetes. Until now, most data suggest that within adipose tissue these factors are secreted by cells of the innate immune system, e. g. macrophages. In the present study we demonstrate that B lymphocyte stimulator (BLyS) is increased in human obesity. In contrast to several pro-inflammatory factors, we found the source of BLyS in human adipose tissue to be the adipocytes rather than immune cells. In grade 3 obese human subjects, expression of BLyS in vivo in adipose tissue is significantly increased (p<0.001). Furthermore, BLyS serum levels are elevated in grade 3 human obesity (862.5+222.0 pg/ml vs. 543.7+60.7 pg/ml in lean controls, p<0.001) and are positively correlated to the BMI (r = 0.43, p<0.0002). In the present study, bariatric surgery significantly altered serum BLyS concentrations. In contrast, weight loss due to a very-low-calorie-formula-diet (800 kcal/d) had no such effect. To examine metabolic activity of BLyS, in a translational research approach, insulin sensitivity was measured in human subjects in vivo before and after treatment with the human recombinant anti-BLyS antibody belimumab. Since BLyS is known to promote B-cell proliferation and immunoglobulin secretion, the present data suggest that adipocytes of grade 3 obese human subjects are able to activate the adaptive immune system, suggesting that in metabolic inflammation in humans both, innate and adaptive immunity, are of pathophysiological relevance.