Osteoarthritis-associated basic calcium phosphate crystals alter immune cell metabolism and promote M1 macrophage polarization.

OBJECTIVE: A number of studies have demonstrated that molecules called 'alarmins' or danger-associated molecular patterns (DAMPs), contribute to inflammatory processes in the OA joint. Metabolic reprogramming of immune cells, including macrophages, is emerging as a prominent player in determining immune cell phenotype and function. The aim of this study was to investigate if basic calcium phosphate (BCP) crystals which are OA-associated DAMPs, impact on macrophage phenotype and metabolism. METHODS: Human monocyte derived macrophages were treated with BCP crystals and expression of M1 (CXCL9, CXCL10) and M2 (MRC1, CCL13)-associated markers was assessed by real-time PCR while surface maturation marker (CD40, CD80 & CD86) expression was assessed by flow cytometry. BCP induced metabolic changes were assessed by Seahorse analysis and glycolytic marker expression (hexokinase 2(HK2), Glut1 and HIF1α) was examined using real-time PCR and immunoblotting. RESULTS: Treatment with BCP crystals upregulated mRNA levels of CXCL9 and CXCL10 while concomitantly downregulating expression of CCL13 and MRC1. Furthermore, BCP-treated macrophages enhanced surface expression of the maturation makers, CD40, CD80 and CD86. BCP-treated cells also exhibited a shift towards glycolysis as evidenced by an increased ECAR/OCR ratio and enhanced expression of the glycolytic markers, HK2, Glut1 and HIF1α. Finally, BCP-induced macrophage activation and alarmin expression was reduced in the presence of the glycolytic inhibitor, 2-DG. CONCLUSIONS: This study not only provides further insight into how OA-associated DAMPs impact on immune cell function, but also highlights metabolic reprogramming as a potential therapeutic target for calcium crystal-related arthropathies.

Myo-inositol in autoimmune thyroiditis, and hypothyroidism.

Myo-inositol (Myo-Ins) plays an important role in thyroid function and autoimmunity. Myo-Ins is the precursor for the synthesis of phosphoinositides, which takes part in the phosphatidylinositol (PtdIns) signal transduction pathway, and plays a decisive role in several cellular processes. In the thyroid cells, PtdIns is involved in the intracellular thyroid-stimulating hormone (TSH) signaling, via Phosphatidylinositol (3,4,5)-trisphosphate (PtdIns(3,4,5)P3) (PIP-3). Moreover, the phosphatidyl inositol 3 kinases (PI3K) family of lipid kinases regulates diverse aspects of T, B, and Tregs lymphocyte behaviour. Different mouse models deficient for the molecules involved in the PIP3 pathway suggest that impairment of PIP3 signaling leads to dysregulation of immune responses and, sometimes, autoimmunity. Studies have shown that cytokines modulate Myo-Ins in thyroid cells. Moreover, clinical studies have shown that after treatment with Myo-inositol plus seleniomethionine (Myo-Ins + Se), TSH levels significantly declined in patients with subclinical hypothyroidism due to autoimmune thyroiditis. The treatment was accompanied by a decline of antithyroid autoantibodies. After treatment serum CXCL10 levels declined, confirming the immune-modulatory effect of Myo-Ins. Additional research is necessary in larger population to evaluate the effect on the quality of life, and to study the mechanism of the effect on chemokines.

Inhibition of Cyclic GMP-AMP Synthase Using a Novel Antimalarial Drug Derivative in Trex1-Deficient Mice.

OBJECTIVE: Type I interferon (IFN) is strongly implicated in the pathogenesis of systemic lupus erythematosus (SLE) as well as rare monogenic interferonopathies such as Aicardi-Goutières syndrome (AGS), a disease attributed to mutations in the DNA exonuclease TREX1. The DNA-activated type I IFN pathway cyclic GMP-AMP (cGAMP) synthase (cGAS) is linked to subsets of AGS and lupus. This study was undertaken to identify inhibitors of the DNA-cGAS interaction, and to test the lead candidate drug, X6, in a mouse model of AGS. METHODS: Trex1-/- mice were treated orally from birth with either X6 or hydroxychloroquine (HCQ) for 8 weeks. Expression of IFN-stimulated genes (ISGs) was quantified by quantitative polymerase chain reaction. Multiple reaction monitoring by ultra-performance liquid chromatography coupled with tandem mass spectrometry was used to quantify the production of cGAMP and X6 drug concentrations in the serum and heart tissue of Trex1-/- mice. RESULTS: On the basis of the efficacy-to-toxicity ratio established in vitro, drug X6 was selected as the lead candidate for treatment of Trex1-/- mice. X6 was significantly more effective than HCQ in attenuating ISG expression in mouse spleens (P < 0.01 for Isg15 and Isg20) and hearts (P < 0.05 for Isg15, Mx1, and Ifnb, and P < 0.01 for Cxcl10), and in reducing the production of cGAMP in mouse heart tissue (P < 0.05), thus demonstrating target engagement by the X6 compound. Of note, X6 was also more effective than HCQ in reducing ISG expression in vitro (P < 0.05 for IFI27 and MX1, and P < 0.01 for IFI44L and PKR) in human peripheral blood mononuclear cells from patients with SLE. CONCLUSION: This study demonstrates that X6 is superior to HCQ for the treatment of an experimental autoimmune myocarditis mediated in vivo by the cGAS/stimulator of IFN genes (cGAS/STING) pathway. The findings suggest that drug X6 could be developed as a novel treatment for AGS and/or lupus to inhibit activation of the cGAS/STING pathway.

Distinct Regulation of CXCL10 Production by Cytokines in Human Salivary Gland Ductal and Acinar Cells.

CXCL10, a CXC chemokine induced by interferon-gamma [IFN-γ], has been observed in a wide variety of chronic inflammatory disorders and autoimmune conditions. Although CXCL10 is known to be overexpressed in the salivary glands of individuals with primary Sjögren's syndrome (pSS), it is unclear which cells produce CXCL10 under what types of stimulations. Here, we investigated the precise molecular mechanisms by which CXCL10 was produced in human salivary gland ductal (NS-SV-DC) and acinar (NS-SV-AC) cell lines. Our results demonstrated that NS-SV-DC cells produced higher levels of CXCL10 compared to NS-SV-AC cells. In addition, our findings demonstrated that the regulator of the enhancement of CXCL10 was different between NS-SV-DC and NS-SV-AC cells, i.e., interferon-gamma (IFN-γ) had more potential than interferon-alpha (IFN-α), tumor necrosis factor (TNF)-α, and interleukin (IL)1-ß in the induction of CXCL10 production in NS-SV-DC cells, whereas TNF-α had potential to induce CXCL10 production in NS-SV-AC cells. A Western blot analysis demonstrated that IFN-γ enhanced the production of CXCL10 via both the JAK/STAT1 pathway and the NF-κB pathway in NS-SV-DC cells, whereas TNF-α enhanced the production of CXCL10 via the NF-κB pathway in NS-SV-AC cells. The results of study suggest that the CXCL10 overexpression in the salivary glands is caused mainly by IFN-γ-stimulated salivary gland ductal cells. The enhanced production of CXCL10 by IFN-γ from ductal cells may result in the inflammation of pSS lesions.

Chronic ethanol consumption: role of TLR3/TRIF-dependent signaling.

Chronic ethanol consumption stimulates neuroimmune signaling in the brain, and Toll-like receptor (TLR) activation plays a key role in ethanol-induced inflammation. However, it is unknown which of the TLR signaling pathways, the myeloid differentiation primary response gene 88 (MyD88) dependent or the TIR-domain-containing adapter-inducing interferon-ß (TRIF) dependent, is activated in response to chronic ethanol. We used voluntary (every-other-day) chronic ethanol consumption in adult C57BL/6J mice and measured expression of TLRs and their signaling molecules immediately following consumption and 24 hours after removing alcohol. We focused on the prefrontal cortex where neuroimmune changes are the most robust and also investigated the nucleus accumbens and amygdala. Tlr mRNA and components of the TRIF-dependent pathway (mRNA and protein) were increased in the prefrontal cortex 24 hours after ethanol and Cxcl10 expression increased 0 hour after ethanol. Expression of Tlr3 and TRIF-related components increased in the nucleus accumbens, but slightly decreased in the amygdala. In addition, we demonstrate that the IKKε/TBK1 inhibitor Amlexanox decreases immune activation of TRIF-dependent pathway in the brain and reduces ethanol consumption, suggesting the TRIF-dependent pathway regulates drinking. Our results support the importance of TLR3 and the TRIF-dependent pathway in ethanol-induced neuroimmune signaling and suggest that this pathway could be a target in the treatment of alcohol use disorders.

Safety, Tolerability, and Pharmacodynamics of ABT-122, a Tumor Necrosis Factor- and Interleukin-17-Targeted Dual Variable Domain Immunoglobulin, in Patients With Rheumatoid Arthritis.

OBJECTIVE: Tumor necrosis factor (TNF) and interleukin-17 (IL-17) independently contribute to the pathophysiology of rheumatoid arthritis (RA). ABT-122 is a novel dual variable domain immunoglobulin that selectively and simultaneously targets human TNF and IL-17A. The aim of treatment with ABT-122 is to evoke a greater clinical response than that achieved by targeting either cytokine alone. This study was undertaken to present the pooled safety, tolerability, and exploratory pharmacodynamics of ABT-122 based on 2 phase I, placebo-controlled, multiple ascending-dose studies in patients with primarily inactive RA. METHODS: Patients (n = 44) receiving stable dosages of methotrexate (2.5-25 mg/week) were randomized to receive subcutaneous placebo, ABT-122 1 mg/kg every other week (4 doses), or ABT-122 0.5, 1.5, or 3 mg/kg weekly (8 doses) and were evaluated through 45 days after the last dose (day 92). Serum samples for the assessment of inflammation markers and chemokines were collected at baseline and on postdose days 3, 5, 8, 15, 29, 57, 64, 78, and 92. RESULTS: No clinically significant findings regarding the safety of ABT-122 were observed. The rates of treatment-emergent adverse events (AEs) were similar in patients receiving ABT-122 and those receiving placebo. Only 1 serious AE (and no systemic hypersensitivity reactions or dose-limiting toxicities) was observed in patients treated with ABT-122. The incidence of infections was similar between patients treated with ABT-122 and those receiving placebo, with no serious infection reported. The levels of CXCL9, CXCL10, CCL23, and soluble E-selectin were significantly decreased following ABT-122 treatment relative to placebo treatment. Although patients had essentially inactive RA, exploratory clinical parameters suggested potential antiinflammatory effects following treatment with ABT-122. CONCLUSION: The results of these phase I studies suggest that dual neutralization of TNF and IL-17 with ABT-122 has characteristics acceptable for further exploration of therapeutic potential in TNF- and IL-17A-driven immune-mediated inflammatory diseases.

Bacterial outer membrane vesicles suppress tumor by interferon-γ-mediated antitumor response.

Gram-negative bacteria actively secrete outer membrane vesicles, spherical nano-meter-sized proteolipids enriched with outer membrane proteins, to the surroundings. Outer membrane vesicles have gained wide interests as non-living complex vaccines or delivery vehicles. However, no study has used outer membrane vesicles in treating cancer thus far. Here we investigate the potential of bacterial outer membrane vesicles as therapeutic agents to treat cancer via immunotherapy. Our results show remarkable capability of bacterial outer membrane vesicles to effectively induce long-term antitumor immune responses that can fully eradicate established tumors without notable adverse effects. Moreover, systematically administered bacterial outer membrane vesicles specifically target and accumulate in the tumor tissue, and subsequently induce the production of antitumor cytokines CXCL10 and interferon-γ. This antitumor effect is interferon-γ dependent, as interferon-γ-deficient mice could not induce such outer membrane vesicle-mediated immune response. Together, our results herein demonstrate the potential of bacterial outer membrane vesicles as effective immunotherapeutic agent that can treat various cancers without apparent adverse effects.Bacterial outer membrane vesicles (OMVs) contain immunogens but no study has yet examined their potential in treating cancer. Here, the authors demonstrate that OMVs can suppress established tumours and prevent tumour metastasis by an interferon-γ mediated antitumor response.

Changes in cytokine and chemokine expression distinguish dysthymic disorder from major depression and healthy controls.

An important area of uncertainty is the inflammatory degree to which depression occurring as part of dysthymic disorder may differ from major depression. Using a 27-plex cytokine assay, we analyzed the serum of 12 patients with dysthymic disorder, 12 with major depression, and an age-, sex-, and body mass index-matched control group of 20 healthy volunteers. We observed that patients with dysthymic disorder exhibited aberrant cytokine and chemokine expression compared with healthy controls and patients with major depression. The levels of interferon-γ-induced protein 10 highly predicted dysthymic disorder. Network analyses revealed that in patients with dysthymic disorder, the vertices were more sparsely connected and adopted a more hub-like architecture, and the connections from neighboring vertices of interleukin 2 and eotaxin-1 increased. After treatment with the same antidepressant, there was no difference between dysthymic disorder and major depression regarding any of the cytokines or chemokines analyzed. For dysthymic disorder, changes in the levels of interferon-γ-induced protein 10 and macrophage inflammatory protein-1α correlated with depression improvement. The findings suggest that the cytokine milieu in dysthymic disorder differs either at the level of individual expression or in network patterns. Moreover, chemokines play an important role in driving the pathophysiology of dysthymic disorder.

Toll-like receptor ligands induce cytokine and chemokine production in human inner ear endolymphatic sac fibroblasts.

OBJECTIVE: Against recent reports concerning cytokine or chemokine in mouse or rat inner ear cells, it is almost unknown whether human inner ear cells would produce cytokine or chemokine. We have for the first time established the human inner-ear-derived fibroblasts from endolymphatic sac. METHODS: The expression levels of Toll-like receptors (TLRs) in human endolymphatic sac fibroblasts, and the effect on cytokine or chemokine production of the TLR ligands have been examined. To demonstrate the intracellular pathways involved in the regulation of cytokine-production, we used specific inhibitors of c-Jun N-terminal kinase (JNK), extracellular signal-related kinase (ERK), p38 mitogen-activated protein kinase (p38 MAPK)-signaling and N-acetyl-l-cysteine (NAC). RESULTS: TLR 2, 3, 4 and 9 were highly expressed in human endolymphatic sac fibroblasts. The TLR 3 ligand, polyinosinic-polycytidylic acid (poly(I:C)) significantly enhanced the secretion of thymic stromal lymphopoietin (TSLP), B lymphocyte stimulator (BLyS), IFNγ-inducible protein 10 (IP-10), and macrophage inflammatory protein 1 alpha (MIP-1α) from the cells. The inhibitor of JNK strongly reduced the poly(I:C)-induced TSLP-production. The antioxidant drug, NAC also reduced the TSLP-production in fibroblasts stimulated with poly(I:C). CONCLUSION: Our findings suggest human inner-ear-endolymphatic sac derived fibroblasts can produce the cytokine and chemokine in response to TLR ligands and play a certain role during the initiation of an immune response.

Phosphodiesterase Type 5 Inhibitor Sildenafil Decreases the Proinflammatory Chemokine CXCL10 in Human Cardiomyocytes and in Subjects with Diabetic Cardiomyopathy.

T helper 1 (Th1) type cytokines and chemokines are bioactive mediators in inflammation underling several diseases and co-morbid conditions, such as cardiovascular and metabolic disorders. Th1 chemokine CXCL10 participates in heart damage initiation/progression; cardioprotection has been recently associated with sildenafil, a type 5 phosphodiesterase inhibitor. We aimed to evaluate the effect of sildenafil on CXCL10 in inflammatory conditions associated with diabetic cardiomyopathy. We analyzed: CXCL10 gene and protein in human cardiac, endothelial, and immune cells challenged by pro-inflammatory stimuli with and without sildenafil; serum CXCL10 in diabetic subjects at cardiomyopathy onset, before and after 3 months of treatment with sildenafil vs. placebo. Sildenafil significantly decreased CXCL10 protein secretion (IC50 = 2.6 × 10(-7)) and gene expression in human cardiomyocytes and significantly decreased circulating CXCL10 in subjects with chemokine basal level ≥ 930 pg/ml, the cut-off value as assessed by ROC analysis. In conclusion, sildenafil could be a pharmacologic tool to control CXCL10-associated inflammation in diabetic cardiomyopathy.

Differential profiles of salivary proteins with affinity to Streptococcus mutans lipoteichoic acid in caries-free and caries-positive human subjects.

Streptococcus mutans is a representative oral pathogen that causes dental caries and pulpal inflammation. Its lipoteichoic acid (Sm.LTA) is known to be an important cell-wall virulence factor involved in bacterial adhesion and induction of inflammation. Since Sm.LTA-binding proteins (Sm.LTA-BPs) might play an important role in pathogenesis and host immunity, we identified the Sm.LTA-BPs in the saliva of caries-free and caries-positive human subjects using Sm.LTA-conjugated beads and LTQ-Orbitrap hybrid Fourier transform mass spectrometry. Sm.LTA was conjugated to N-hydroxysuccinimidyl-Sepharose(®) 4 Fast Flow beads (Sm.LTA-beads). Sm.LTA retained its biological properties during conjugation, as determined by the expression of nitric oxide and interferon-γ-inducible protein 10 in a murine macrophage cell line and activation of Toll-like receptor 2 (TLR2) in CHO/CD14/TLR2 cells. Sm.LTA-BPs were isolated from pooled saliva prepared from 10 caries-free or caries-positive human subjects each, electrophoresed to see their differential expression in each group, and further identified by high-resolution mass spectrometry. A total of 8 and 12 Sm.LTA-BPs were identified with statistical significance in the pooled saliva from the caries-free and caries-positive human subjects, respectively. Unique Sm.LTA-BPs found in caries-free saliva included histone H4, profilin-1 and neutrophil defensin-1, and those in caries-positive saliva included cystatin-C, cystatin-SN, cystatin-S, cystatin-D, lysozyme C, calmodulin-like protein 3 and ß-actin. The Sm.LTA-BPs found in both groups were hemoglobin subunits α and ß, prolactin-inducible protein, protein S100-A9, and SPLUNC2. Collectively, we identified Sm.LTA-BPs in the saliva of caries-free and caries-positive subjects, which exhibit differential protein profiles.

Xylitol, an anticaries agent, exhibits potent inhibition of inflammatory responses in human THP-1-derived macrophages infected with Porphyromonas gingivalis.

BACKGROUND: Xylitol is a well-known anticaries agent and has been used for the prevention and treatment of dental caries. In this study, the anti-inflammatory effects of xylitol are evaluated for possible use in the prevention and treatment of periodontal infections. METHODS: Cytokine expression was stimulated in THP-1 (human monocyte cell line)-derived macrophages by live Porphyromonas gingivalis, and enzyme-linked immunosorbent assay and a commercial multiplex assay kit were used to determine the effects of xylitol on live P. gingivalis-induced production of cytokine. The effects of xylitol on phagocytosis and the production of nitric oxide were determined using phagocytosis assay, viable cell count, and Griess reagent. The effects of xylitol on P. gingivalis adhesion were determined by immunostaining, and costimulatory molecule expression was examined by flow cytometry. RESULTS: Live P. gingivalis infection increased the production of representative proinflammatory cytokines, such as tumor necrosis factor-α and interleukin (IL)-1ß, in a multiplicity of infection- and time-dependent manner. Live P. gingivalis also enhanced the release of cytokines and chemokines, such as IL-12 p40, eotaxin, interferon γ-induced protein 10, monocyte chemotactic protein-1, and macrophage inflammatory protein-1. The pretreatment of xylitol significantly inhibited the P. gingivalis-induced cytokines production and nitric oxide production. In addition, xylitol inhibited the attachment of live P. gingivalis on THP-1-derived macrophages. Furthermore, xylitol exerted antiphagocytic activity against both Escherichia coli and P. gingivalis. CONCLUSION: These findings suggest that xylitol acts as an anti-inflammatory agent in THP-1-derived macrophages infected with live P. gingivalis, which supports its use in periodontitis.

CXCL10-CXCR3 enhances the development of neutrophil-mediated fulminant lung injury of viral and nonviral origin.

RATIONALE: Patients who developed acute respiratory distress syndrome (ARDS) after infection with severe respiratory viruses (e.g., severe acute respiratory syndrome-coronavirus, H5N1 avian influenza virus), exhibited unusually high levels of CXCL10, which belongs to the non-ELR (glutamic-leucine-arginine) CXC chemokine superfamily. CXCL10 may not be a bystander to the severe virus infection but may directly contribute to the pathogenesis of neutrophil-mediated, excessive pulmonary inflammation. OBJECTIVES: We investigated the contribution of CXCL10 and its receptor CXCR3 axis to the pathogenesis of ARDS with nonviral and viral origins. METHODS: We induced nonviral ARDS by acid aspiration and viral ARDS by intratracheal influenza virus infection in wild-type mice and mice deficient in CXCL10, CXCR3, IFNAR1 (IFN-α/ß receptor 1), or TIR domain-containing adaptor inducing IFN-ß (TRIF). MEASUREMENTS AND MAIN RESULTS: We found that the mice lacking CXCL10 or CXCR3 demonstrated improved severity and survival of nonviral and viral ARDS, whereas mice that lack IFNAR1 did not control the severity of ARDS in vivo. The increased levels of CXCL10 in lungs with ARDS originate to a large extent from infiltrated pulmonary neutrophils, which express a unique CXCR3 receptor via TRIF. CXCL10-CXCR3 acts in an autocrine fashion on the oxidative burst and chemotaxis in the inflamed neutrophils, leading to fulminant pulmonary inflammation. CONCLUSIONS: CXCL10-CXCR3 signaling appears to be a critical factor for the exacerbation of the pathology of ARDS. Thus, the CXCL10-CXCR3 axis could represent a prime therapeutic target in the treatment of the acute phase of ARDS of nonviral and viral origins.

Pentoxifylline reduces tumor necrosis factor-α and HIV-induced vascular endothelial activation.

Untreated HIV infection is associated with endothelial dysfunction and subsequent cardiovascular disease, likely due to both direct effects of the virus and to indirect effects of systemic inflammation on the vasculature. We have recently shown that treatment with the antiinflammatory agent pentoxifylline (PTX) improved in vivo endothelial function and reduced circulating levels of the inflammatory markers vascular cell adhesion molecule-1 (VCAM-1) and interferon-gamma-induced protein (IP-10) in HIV-infected patients. To delineate the mechanisms underlying this therapeutic effect, we tested whether clinically relevant concentrations of PTX suppress VCAM-1 or IP-10 release in cultivated human lung microvascular endothelial cells. Indeed, we found that tumor necrosis factor (TNF)-α-induced VCAM-1 was reduced with concentrations of PTX in the low nanomolar range, comparable to plasma levels in PTX-treated groups. We also investigated the effect of HIV proteins and found that HIV transactivator of transcription (HIV-Tat) and HIV-envelope-derived recombinant gp120 enhanced TNF-α-induced VCAM-1 gene expression in lung microvascular and coronary macrovascular endothelial cells, respectively. In addition, PTX and a NF-κB-specific inhibitor reduced this enhanced VCAM-1 gene induction in microvascular and macrovascular endothelial cells. These results provide novel insights in how the antiinflammatory agent PTX can directly reduce HIV-associated proinflammatory endothelial activation, which may underlie vascular dysfunction and coronary vascular diseases.

Effect of hydroxychloroquine treatment on pro-inflammatory cytokines and disease activity in SLE patients: data from LUMINA (LXXV), a multiethnic US cohort.

OBJECTIVE: We sought to determine the effect of hydroxychloroquine therapy on the levels proinflammatory/prothrombotic markers and disease activity scores in patients with systemic lupus erythematosus (SLE) in a multiethnic, multi-center cohort (LUMINA). METHODS: Plasma/serum samples from SLE patients (n = 35) were evaluated at baseline and after hydroxychloroquine treatment. Disease activity was assessed using SLAM-R scores. Interferon (IFN)-α2, interleukin (IL)-1ß, IL-6, IL-8, inducible protein (IP)-10, monocyte chemotactic protein-1, tumor necrosis factor (TNF)-α and soluble CD40 ligand (sCD40L) levels were determined by a multiplex immunoassay. Anticardiolipin antibodies were evaluated using ELISA assays. Thirty-two frequency-matched plasma/serum samples from healthy donors were used as controls. RESULTS: Levels of IL-6, IP-10, sCD40L, IFN-α and TNF-α were significantly elevated in SLE patients versus controls. There was a positive but moderate correlation between SLAM-R scores at baseline and levels of IFN-α (p = 0.0546). Hydroxychloroquine therapy resulted in a significant decrease in SLAM-R scores (p = 0.0157), and the decrease in SLAM-R after hydroxychloroquine therapy strongly correlated with decreases in IFN-α (p = 0.0087). CONCLUSIONS: Hydroxychloroquine therapy resulted in significant clinical improvement in SLE patients, which strongly correlated with reductions in IFN-α levels. This indicates an important role for the inhibition of endogenous TLR activation in the action of hydroxychloroquine in SLE and provides additional evidence for the importance of type I interferons in the pathogenesis of SLE. This study underscores the use of hydroxychloroquine in the treatment of SLE.

Activation of innate immunity accelerates sialoadenitis in a mouse model for Sjögren's syndrome-like disease.

OBJECTIVE: Sjögren's syndrome is a chronic autoimmune disorder characterized by progressive lymphocytic infiltration within the salivary and lacrimal glands. This study was undertaken to investigate the effects of innate immunity activation on sialoadenitis in a mouse strain genetically susceptible for development of SS-like disease. METHODS: Female New Zealand Black X New Zealand White F1 mice were repeatedly treated with toll-like 3 receptor agonist poly(I:C). Submandibular glands were investigated at different time points for sialoadenitis by immunohistochemistry and for gene expression of different chemokines by quantitative PCR. Submandibular gland-infiltrating cells were characterized by flow cytometry. RESULTS: Poly(I:C) treatment significantly upregulated the expression of multiple chemokines within the submandibular glands. The severity and incidence of sialoadenitis was considerably higher in poly(I:C)-treated mice. There was a preponderance of dendritic cells and NK cells in the initial inflammatory cell infiltrates, and these were followed by CD4+ T cells. CONCLUSIONS: Our data clearly demonstrate that systemic activation of innate immunity accelerates sialoadenitis in a mouse model for SS-like disease. These findings suggest that chronic activation of innate immunity can influence certain features of SS.

Genome-wide transcriptional profiling analysis of all trans retinoic acid-treated tongue carcinoma SCC-9 cells.

BACKGROUND: All trans retinoic acid (ATRA) is used as standard of care in promyelocytic leukemia. Not much is known about the gene expression profile in ATRA-treated tongue cancer cells. We performed a genome-wide transcriptional profiling of ATRA-treated tongue cancer cells to understand the pathways that mediate ATRA action in tongue cancer. METHODS: We measured the effects of ATRA on the proliferation of SCC-9 human tongue carcinoma cells. The differential gene expression profile was measured by microarray analysis of untreated and ATRA-treated cells and expression of key genes was validated by real-time RT-PCR. RESULTS: ATRA treatment (24 and 48 hr) significantly inhibited SCC-9 cell proliferation in a dose-dependent manner. SCC-9 cells treated for 48 hr with ATRA showed upregulation of 276 genes, including ANGPTL4, GDF15, ICAM1 and TUSC4, and downregulation of 43 genes, including CXCL10. Validation by real-time PCR showed a significant upregulation of intracellular adhesion molecule 1 (ICAM1) and downregulation of CXCL10 and IL32. CONCLUSIONS: ATRA had an anti-tumor effect in tongue cancer cells. This effect is likely mediated via upregulation of ICAM1 and downregulation of CXCL10 and IL32.

The effect of HIV infection and HAART on inflammatory biomarkers in a population-based cohort of women.

OBJECTIVE: HIV causes inflammation that can be at least partially corrected by HAART. To determine the qualitative and quantitative nature of cytokine perturbation, we compared cytokine patterns in three HIV clinical groups, including HAART responders (HAART), untreated HIV noncontrollers, and HIV-uninfected (NEG). METHODS: Multiplex assays were used to measure 32 cytokines in a cross-sectional study of participants in the Women's Interagency HIV Study. Participants from three groups were included: HAART (n = 17), noncontrollers (n = 14), and HIV NEG (n = 17). RESULTS: Several cytokines and chemokines showed significant differences between noncontrollers and NEG participants, including elevated interferon gamma-induced 10 (IP-10) and tumor necrosis factor-α (TNF-α) and decreased interleukin-12(p40) [IL-12(p40)], IL-15, and fibroblast growth factor-2 (FGF-2) in noncontroller participants. Biomarker levels among HAART women more closely resembled the NEG, with the exception of TNF-α and FGF-2. Secondary analyses of the combined HAART and noncontroller groups revealed that IP-10 showed a strong, positive correlation with viral load and negative correlation with CD4(+) T-cell counts. The growth factors vascular endothelial growth factor, epidermal growth factor, and FGF-2 all showed a positive correlation with increased CD4(+) T-cell counts. CONCLUSION: Untreated, progressive HIV infection was associated with decreased serum levels of cytokines important in T-cell homeostasis (IL-15) and T-cell phenotype determination (IL-12), and increased levels of innate inflammatory mediators such as IP-10 and TNF-α. HAART was associated with cytokine profiles that more closely resembled those of HIV-uninfected women. The distinctive pattern of cytokine levels in the three study groups may provide insights into HIV pathogenesis, and responses to therapy.