The immune regulatory function of B7-H3 in malignancy: spotlight on the IFN-STAT1 axis and regulation of tumor-associated macrophages.

B7-H3 is a member of the B7 superfamily and a putative inhibitory immune checkpoint molecule. Several early-phase clinical trials have reported promising anti-tumor activity and safety of anti-cancer drugs targeting B7-H3, suggesting that it may be a promising target for a potential next-generation immune checkpoint inhibitor. Despite ongoing clinical studies, most B7-H3-targeted drugs being currently investigated rely on direct cytotoxicity as their mechanisms of action rather than modulating its function as an immune checkpoint, at least in part due to its incompletely understood immune regulatory function. Recent studies have begun to elucidate the role of B7-H3 in regulating the tumor microenvironment (TME). Emerging evidence suggests that B7-H3 may regulate the interferon-STAT1 axis in the TME and promote immune suppression. Similarly, increasing evidence shows B7-H3 may be implicated in promoting M1 to M2 polarization of tumor-associated macrophages (TAMs). There is also accumulating evidence suggesting that B7-H3 may play a role in the heterotypic fusion of cancer stem cells and macrophages, thereby promoting tumor invasion and metastasis. Here, we review the recent advances in the understanding of B7-H3 cancer immunobiology with a focus on highlighting its potential role in the interferon priming of TAMs and the heterotypic fusion of TAMs with cancer stem cells and suggest future direction in elucidating its immune checkpoint function.

Inhibition of Human Osteoclast Differentiation by Kynurenine through the Aryl-Hydrocarbon Receptor Pathway.

Aryl-hydrocarbon receptor (AhR) is a ligand-activated transcription factor and regulates differentiation and function of various immune cells such as dendritic cells, Th17, and regulatory T cells. In recent studies, it was reported that AhR is involved in bone remodeling through regulating both osteoblasts and osteoclasts. However, the roles and mechanisms of AhR activation in human osteoclasts remain unknown. Here we show that AhR is involved in human osteoclast differentiation. We found that AhR expressed highly in the early stage of osteoclastogenesis and decreased in mature osteoclasts. Kynurenine (Kyn), formylindolo[3,4-b] carbazole (FICZ), and benzopyrene (BaP), which are AhR agonists, inhibited osteoclast formation and Kyn suppressed osteoclast differentiation at an early stage. Furthermore, blockade of AhR signaling through CH223191, an AhR antagonist, and knockdown of AhR expression reversed Kyn-induced inhibition of osteoclast differentiation. Overall, our study is the first report that AhR negatively regulates human osteoclast differentiation and suggests that AhR could be good therapeutic molecule to prevent bone destruction in chronic inflammatory diseases such as rheumatoid arthritis (RA).

B7-H3 regulates osteoclast differentiation via type I interferon-dependent IDO induction.

While their function, as immune checkpoint molecules, is well known, B7-family proteins also function as regulatory molecules in bone remodeling. B7-H3 is a receptor ligand of the B7 family that functions primarily as a negative immune checkpoint. While the regulatory function of B7-H3 in osteoblast differentiation has been established, its role in osteoclast differentiation remains unclear. Here we show that B7-H3 is highly expressed in mature osteoclasts and that B7-H3 deficiency leads to the inhibition of osteoclastogenesis in human osteoclast precursors (OCPs). High-throughput transcriptomic analyses reveal that B7-H3 inhibition upregulates IFN signaling as well as IFN-inducible genes, including IDO. Pharmacological inhibition of type-I IFN and IDO knockdown leads to reversal of B7-H3-deficiency-mediated osteoclastogenesis suppression. Although synovial-fluid macrophages from rheumatoid-arthritis patients express B7-H3, inhibition of B7-H3 does not affect their osteoclastogenesis. Thus, our findings highlight B7-H3 as a physiologic positive regulator of osteoclast differentiation and implicate type-I IFN-IDO signaling as its downstream mechanism.

Augmenting MNK1/2 activation by c-FMS proteolysis promotes osteoclastogenesis and arthritic bone erosion.

Osteoclasts are bone-resorbing cells that play an essential role in homeostatic bone remodeling and pathological bone erosion. Macrophage colony stimulating factor (M-CSF) is abundant in rheumatoid arthritis (RA). However, the role of M-CSF in arthritic bone erosion is not completely understood. Here, we show that M-CSF can promote osteoclastogenesis by triggering the proteolysis of c-FMS, a receptor for M-CSF, leading to the generation of FMS intracellular domain (FICD) fragments. Increased levels of FICD fragments positively regulated osteoclastogenesis but had no effect on inflammatory responses. Moreover, myeloid cell-specific FICD expression in mice resulted in significantly increased osteoclast-mediated bone resorption in an inflammatory arthritis model. The FICD formed a complex with DAP5, and the FICD/DAP5 axis promoted osteoclast differentiation by activating the MNK1/2/EIF4E pathway and enhancing NFATc1 protein expression. Moreover, targeting the MNK1/2 pathway diminished arthritic bone erosion. These results identified a novel role of c-FMS proteolysis in osteoclastogenesis and the pathogenesis of arthritic bone erosion.

The Role of Aryl-Hydrocarbon Receptor (AhR) in Osteoclast Differentiation and Function.

Aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that plays a crucial role in bone remodeling through altering the interplay between bone-forming osteoblasts and bone-resorbing osteoclasts. While effects of AhR signaling in osteoblasts are well understood, the role and mechanism of AhR signaling in regulating osteoclastogenesis is not widely understood. AhR, when binding with exogenous ligands (environmental pollutants such as polycylic aryl hydrocarbon (PAH), dioxins) or endogenous ligand indoxyl-sulfate (IS), has dual functions that are mediated by the nature of the binding ligand, binding time, and specific pathways of distinct ligands. In this review, AhR is discussed with a focus on (i) the role of AhR in osteoclast differentiation and function and (ii) the mechanisms of AhR signaling in inhibiting or promoting osteoclastogenesis. These findings facilitate an understanding of the role of AhR in the functional regulation of osteoclasts and in osteoclast-induced bone destructive conditions such as rheumatoid arthritis and cancer.

1,25-Dihydroxyvitamin D3 induces human myeloid cell differentiation via the mTOR signaling pathway.

1,25-Dihydroxyvitamin D3 or 1,25(OH)2D3 is known to play an important role in the differentiation of human myeloid cells. However, the molecular mechanism underlying the 1,25(OH)2D3-mediated differentiation of human myeloid cells is incompletely understood. Here, we report that 1,25(OH)2D3 induces differentiation of human myeloid cell lines such as U937 and THP-1 cells via the mammalian target of rapamycin (mTOR) signaling pathway. Both the expression of the differentiation marker CD14 and activation of the mTOR signaling pathway were induced by 1,25(OH)2D3 in phorbol 12-myristate 13-acetate (PMA)-differentiated U937 and THP-1 cells. The 1,25(OH)2D3-induced expression of CD14 in PMA-differentiated U937 and THP-1 cells was prevented by mTOR inhibitors, PP242 and Torin1. The 1,25(OH)2D3-induced morphological changes as characteristics of differentiated myeloid cells were also reversed after PP242 and Torin1 treatment. Silencing of either regulatory-associated protein of mTOR (Raptor) or rapamycin-insensitive companion of mTOR (Rictor) in PMA-differentiated THP-1 cells with small-interfering RNA resulted in the inhibition of CD14 expression and morphological changes induced by 1,25(OH)2D3, indicating that both mTORC1 and mTORC2 were important for the differentiation of myeloid THP-1 cells. Previous studies have shown that phosphatidic acid (PA) maintains the stability of the mTOR complex. Here we found that the attenuation of PA production with 1-butanol or a PLD inhibitor prevented the 1,25(OH)2D3-induced upregulation of CD14. Taken together, our results show that 1,25(OH)2D3 enhances the differentiation of human myeloid cells through the mTOR signaling pathway.

A dual role of TGF-ß in human osteoclast differentiation mediated by Smad1 versus Smad3 signaling.

TGF-ß1 is highly expressed in the synovial tissue of patients with rheumatoid arthritis and is known as a cytokine that plays an important role in tissue repair and immune cell regulation. However, the role of TGF-ß1 is still unclear in osteoclastogenesis. In this study, we examined the effect of TGF-ß1 on osteoclast differentiation and the underlying mechanism using healthy human peripheral blood monocytes. TGF-ß1 was found to inhibit osteoclast differentiation and decrease the expression of osteoclast-specific genes such as acid phosphatase 5, tartrate resistant and cathepsin K. Levels of NFAT1, an important transcription factor in osteoclastogenesis, were also reduced. In addition, TGF-ß1 suppressed receptor activator of NF-κB (RANK) ligand-induced NF-κB and p38 MAPK signaling. Inhibition of osteoclast differentiation by TGF-ß1 was reversed by 1 µM SB431542 (an inhibitor of ALK4/5/7), which inhibited TGF-ß1-induced phosphorylation of SMAD1, but not that of SMAD3. TGF-ß1 also restricted RANK expression, and this was partially reversed by 1 µM SB431542. In contrast, the inhibition of SMAD3 by SIS3 (an inhibitor of SMAD3) reduced the osteoclast formation. TGF-ß1 has both inhibitory and stimulatory effects on human osteoclast differentiation, and that these opposing functions are mediated by SMAD1 and SMAD3 signaling, respectively.

Poly-γ-glutamic acid suppresses osteoclastogenesis in human osteoclast precursors and prevents joint damage in a collagen-induced murine arthritis model.

Poly-γ-glutamic acid (γ-PGA), a natural polymer derived from Bacillus subtilis, shows anti-inflammatory activity. However, the effects of γ-PGA on osteoclasts, which are important cells for joint destruction in inflammatory diseases such as rheumatoid arthritis (RA), have not yet been reported. In this study, we show that γ-PGA markedly inhibits osteoclast differentiation in normal PBMC-derived osteoclast precursors and in synovial fluid macrophages of patients with RA. γ-PGA also reduces RANK expression by down-regulating M-CSF receptors. Additionally, oral administration of γ-PGA attenuated bone destruction in a collagen-induced arthritis (CIA) model, demonstrating decreases in inflammation, cartilage damage, and osteoclast formation in histological analyses. Taken together, these data suggest that γ-PGA could be a good candidate for therapeutic prevention of joint destruction in RA.

Metabolic syndrome: prevalence and risk factors in Korean gout patients.

Background/Aims: We performed this study to investigate associations between metabolic syndrome, chronic kidney disease (CKD), and gout. METHODS: We reviewed the medical records of 151 patients with gout at the Department of Rheumatology in Korea University Ansan Hospital. The following measures were examined: waist circumference, blood pressure, alcohol consumption, and levels of triglyceride, high density lipoprotein cholesterol, fasting serum glucose, serum uric acid (SUA), creatinine, insulin, and C-peptide. We assessed metabolic syndrome by the homeostasis model assessment of insulin resistance (HOMA-IR) index and renal function by the Modification of Diet in Renal Disease equation; patients were classified according to World Health Organization Asia-Pacific obesity criteria. RESULTS: The prevalence of metabolic syndrome in gout patients (50.8%) was higher than in non-gout patients. The mean SUA level was significantly higher in gout patients with metabolic syndrome (9.13 ± 3.15 mg/dL) than in gout patients without metabolic syndrome (8.14 ± 2.07 mg/dL). The mean SUA level was also significantly higher in patients with gout and CKD (9.55 ± 2.86 mg/dL) than in patients with gout but no CKD (7.74 ± 2.27 mg/dL). In gout patients, HOMA-IR was positively correlated with waist circumference (r = 0.409, p = 0.001). Conclusions: The prevalence of metabolic syndrome in patients with gout was 50.8%, which is higher than the prevalence in the general Korean population. Hyperuricemia in gout patients was correlated with metabolic syndrome and CKD. Insulin resistance may provide clues to better understand the relationship between metabolic syndrome, CKD, and gout.

Survival and prognostic factors in patients with connective tissue disease-associated pulmonary hypertension diagnosed by echocardiography: results from a Korean nationwide registry.

OBJECTIVES: Pulmonary arterial hypertension (PAH) is a major cause of mortality in connective tissue disease (CTD). The survival rates and mortality-predictive factors of a nationwide registry of Korean patients with CTD-PH measured by echocardiography were determined. METHODS: Patients with CTD-PH were enrolled between April 2008 and December 2012. Hemodynamic parameters and clinical data (WHO-functional class [FC], organ involvement, laboratory tests and treatment agents) were recorded. Survival rates were calculated by using the Kaplan-Meier method. Mortality-associated factors were examined by Cox proportional hazards regression analysis. RESULTS: In total, 174 incident PH cases (61 with systemic lupus erythematosus, 50 with systemic sclerosis, 10 with mixed CTD, 22 with rheumatoid arthritis (RA) and 31 with other CTDs) were diagnosed by Doppler echocardiography. Of these, 25 (14%) died during the 3.8 ± 2.7 year follow-up period after PH diagnosis. The 1- and 3-year survival rates were 90.7% and 87.3%, respectively. Compared to the other CTD-PHs, RA-PH had the lowest survival rates (56% 3 year survival; P = 0.022). Multiple regression analysis revealed that low diffusion capacity of carbon monoxide (DLCO), pleural effusion and diabetes mellitus were poor prognostic factors (P = 0.008, 0.04 and 0.009, respectively). Anti-UI-RNP (ribonucleoprotein) antibody positivity was protective (P = 0.022). In patients with WHO-FC III/IV, patients who received vasodilators had lower mortality than those who did not (P = 0.038). CONCLUSIONS: In Korean patients with CTD-PH, the 3-year survival rate was 87%. Low diffusion capacity of carbon monoxide (DLCO), pleural effusion and diabetes mellitus were independent poor prognostic factors. Anti-UI-RNP antibody was protective. Prompt PAH-specific vasodilator therapy may improve the survival of patients with severe CTD-PH.

Associations between functional FCGR2A R131H and FCGR3A F158V polymorphisms and responsiveness to TNF blockers in spondyloarthropathy, psoriasis and Crohn's disease: a meta-analysis.

AIM: The aim of the current study was to investigate whether FCGR polymorphisms are associated with responsiveness to anti-TNF-α therapy in patients with spondyloarthropathy, psoriasis, and Crohn's disease. MATERIALS & METHODS: We conducted a meta-analysis to evaluate the association between the functional FCGR3A F158V and FCGR2A R131H polymorphisms and responsiveness to TNF blockers. RESULTS: The meta-analysis indicated that responsiveness to TNF blockers was associated with the FCGR3A V allele (odds ratio: 3.308; 95% CI: 1.053-10.39; p = 0.040) and the FCGR2A RR + RH genotype (odds ratio: 3.904; p = 0.027) in patients with a follow-up time of ≥6 months. CONCLUSION: FCGR3A V and FCGR2A R allele carriers show better responsiveness to anti-TNF-α therapy in patients with follow-up times ≥6 months.

Association between the three functional miR-146a single-nucleotide polymorphisms, rs2910164, rs57095329, and rs2431697, and autoimmune disease susceptibility: A meta-analysis.

Studies suggest associations between the miR-146a single nucleotide polymorphisms (SNPs) and susceptibility to autoimmune diseases. However, the results are inconsistent and inconclusive. Therefore, the aim of this study was to arrive at a conclusion about the association between the three functional miR-146a SNPs and autoimmune disease risk. Studies were identified through PubMed/MEDLINE searches for studies published up to January 2016 using as keywords rs2910164, rs57095329, rs2431697, and miR-146a polymorphisms. Thirty studies were included in the meta-analysis. The SNP rs2910164 G > C was found to be associated with increased risk of multiple sclerosis (CC + CG versus GG, OR = 1.25, 95% CI: 1.01-1.55), with decreased risks of psoriasis (C versus G, OR = 0.81, 95% CI: 0.69-0.96; CC versus GC + GG, OR = 0.73, 95% CI: 0.56-0.94), Behcet's disease (CC versus GC + GG, OR = 0.60, 95% CI: 0.50-0.73), asthma (C versus G, OR = 0.80, 95% CI: 0.69-0.93; CC versus GC + GG, OR = 0.65, 95% CI: 0.48-0.86), and uveitis (CC + CG versus GG, OR = 0.61, 95% CI: 0.49-0.77). The SNP rs2431697 C > T was found to be associated with an increased risk of SLE (T versus C, OR = 1.26, 95% CI: 1.15-1.38; TC + TT versus CC, OR = 1.28, 95% CI: 1.03-1.58; TT versus TC + CC, OR = 1.40, 95% CI: 1.21-1.62). The SNP rs57095329 A > G was found to be associated with an increased risk of SLE (G versus C, OR = 1.25, 95% CI: 1.17-1.35). The miR-146a SNPs rs2910164, rs57095329, rs2431697 are associated with susceptibility to certain autoimmune diseases. However, for other autoimmune diseases, they may be protective or insignificant.

Unique gene expression profile in osteoarthritis synovium compared with cartilage: analysis of publicly accessible microarray datasets.

The purpose of this study was to identify a gene expression signature in osteoarthritis (OA) synovium and genomic pathways likely to be involved in the pathogenesis of OA. Four publicly accessible microarray studies from synovium of OA patients were integrated, and a transcriptomic and network-based meta-analysis was performed. Based on pathways according to the Kyoto Encyclopedia of Genes and Genomes, functional enrichment analysis was performed. Meta-analysis results of OA synovium were compared to two previously published studies of OA cartilage to determine the relative number of common and specific DEGs of the cartilage and synovium. According to our meta-analysis, a total of 1350 genes were found to be differentially expressed in the synovium of OA patients as compared to that of healthy controls. Pathway analysis found 41 significant pathways in the total DEGs, and 22 and 16 pathways in the upregulated and downregulated DEGs, respectively. Cell adhesion molecules and cytokine-cytokine receptor interaction were the most significant pathway in the upregulated and downregulated DEGs, respectively. Comparison of meta-analysis results of OA synovium with results of two previous studies of OA cartilage identified 85 common genes and 1632 cartilage-specific DEGs and 1265 synovium-specific DEGs in the first study; and 142 common genes, and 856 cartilage-specific DEGs and 1208 synovium-specific DEGs in the second study. Our results show a small overlap between the DEGs of the synovium compared to DEGs of the cartilage, suggesting different pathogenic mechanisms that are specific to the synovium.

Panenteritis as an Initial Presentation of Systemic Lupus Erythematosus.

Lupus enteritis is a rare, severe complication of systemic lupus erythematosus (SLE), needing prompt diagnosis and proper management. However, SLE rarely presents as lupus enteritis at the time of initial diagnosis. Thus, delayed diagnosis and misdiagnosis are common. We report a case of a 25-year-old woman with lupus panenteritis. The patient had multiple hospitalizations for abdominal pain, nausea, and diarrhea, initially without any other symptoms suggestive of SLE, but was later observed to have malar rash and oral ulcers. Laboratory investigations were compatible with SLE, including positive antinuclear antibody (1:320) with speckled pattern. CT revealed diffuse hypodense submucosal thickening of the stomach, the entire small bowel, colon, appendix, and rectum. Treatment with high-dose corticosteroids followed by maintenance therapy with mycophenolate mofetil, hydroxychloroquine, and azathioprine resulted in clinical improvement. Diagnosis of lupus enteritis requires a high index of suspicion given the low incidence and nonspecific clinical findings.

Calcium channels: the potential therapeutic targets for inflammatory bone destruction of rheumatoid arthritis.

INTRODUCTION: Inflammatory bone resorption causes progressive joint destruction which ultimately leads to functional disability in rheumatoid arthritis (RA). The primary cell responsible for bone resorption is the osteoclast, which means it is a potential therapeutic target against bone destruction. In fact, experimental and clinical findings suggest that blockade of osteoclast differentiation and function is highly effective in inhibiting bone destruction in RA. DISCUSSION AND CONCLUSION: In this report, we show several lines of experimental evidence which suggest that a variety of Ca(2+) channels are essential in osteoclast differentiation and function, and present a hypothesis that modulation of Ca(2+) channels is a highly effective therapeutic strategy in preventing osteoclast-induced structural damage in RA.

TREM-1, a negative regulator of human osteoclastogenesis.

Triggering receptor expressed on myeloid cells (TREMs) are a family of cell surface receptors that play important roles in innate and adaptive immunity. Among them, TREM-2 has been extensively studied for its role in osteoclast differentiation and its essential role in human osteoclastogenesis has been well established. However, much less has been discovered about the role of TREM-1 in human osteoclast differentiation. In this study, we investigate the role of TREM-1 in human osteoclast differentiation. Consistent with previous reports, TREM-2 expression was strongly increased during the generation of human osteoclast precursors. In contrast, TREM-1 expression was decreased during the generation of human osteoclast precursors. Stimulation of TREM-1 using agonistic anti-TREM-1 antibody resulted in suppression of RANKL-induced osteoclastogenesis, as evidenced by diminished formation of TRAP+ multinucleated cells. In addition, TREM-1 stimulation strongly suppressed RANKL-induced expression of osteoclast-related genes such as cathepsin K and NFATc1. TREM-1 stimulation also down-regulated gene expression and cell surface expression of M-CSF receptor that is essential for osteoclast differentiation and survival. In synovial fluid macrophages of rheumatoid arthritis (RA) patients, TREM-1 stimulation suppressed osteoclastogenesis. In conclusion, we demonstrate that TREM-1 acts as a negative regulator of human osteoclast differentiation and identify a novel mechanism of negative regulation of osteoclastogenesis that plays a role in inflammation.

Relative efficacy and tolerability of etoricoxib, celecoxib, and naproxen in the treatment of osteoarthritis : A Bayesian network meta-analysis of randomized controlled trials based on patient withdrawal.

AIMS: This study aimed to assess the relative efficacy and tolerability of etoricoxib, celecoxib, and naproxen at recommended dosages in patients with osteoarthritis (OA). METHODS: Randomized controlled trials (RCTs) examining the efficacy and tolerability of etoricoxib 30-60 mg, celecoxib 200-400 mg, and naproxen 1000 mg, based on the number of patient withdrawals among those with OA, were included in this network meta-analysis. We performed a Bayesian random-effects network meta-analysis to combine direct and indirect evidence from the RCTs. RESULTS: Eight RCTs, including 5,942 patients, met the inclusion criteria. The proportion of patient withdrawals due to lack of efficacy was significantly lower in the etoricoxib 30-60 mg (OR 0.21, 95 % CrI 0.12-0.38), celecoxib 200-400 mg (OR 0.29, 95 % CrI 0.18-0.47), and naproxen 1000 mg (OR 0.31, 95 % CrI 0.18-0.51) groups than in the placebo group. The number of patient withdrawals due to lack of efficacy tended to be lower in the etoricoxib 30-60 mg group than in the naproxen 1000 mg and celecoxib 200-400 mg groups, although they did not reach statistical significance (OR 0.68, 95 % CrI 0.36-1.33 and OR 0.70, 95 % CrI 0.38-1.37, respectively). Ranking probabilities based on the surface under the cumulative ranking curve (SUCRA) indicated that etoricoxib 30-60 mg had the highest probability of being the best treatment based on the number of withdrawals due to lack of efficacy (SUCRA = 0.9168) followed by celecoxib 200-400 mg (SUCRA = 0.5659), naproxen 1000 mg (SUCRA = 0.5171), and placebo (SUCRA = 0.000189). With respect to tolerability, the number of withdrawals due to adverse events was not significantly different among etoricoxib, celecoxib, naproxen, and placebo, although it tended to be lower with etoricoxib and placebo. CONCLUSIONS: Etoricoxib 30-60 mg, celecoxib 200-400 mg, and naproxen 1000 mg were more efficacious than placebo. However, there was no significant difference in efficacy and tolerability between the medications.

Association between FCGR3B copy number variations and susceptibility to autoimmune diseases: a meta-analysis.

OBJECTIVE: This study determined whether FCGR3B copy number variations (CNVs) were associated with susceptibility to autoimmune diseases. METHODS: A meta-analysis was conducted to determine the association between FCGR3B CNVs and susceptibility to autoimmune diseases by comparing low FCGR3B CN (<2 to ≥2) and high FCGR3B CN (>2 to ≤2). RESULTS: In all, 28 comparative studies from 15 reports involving 12,160 patients and 11,103 controls were included in this meta-analysis. The meta-analysis showed a significant association between low FCGR3B CN and autoimmune diseases (OR=1.496, 95% CI=1.301-1.716, p=1.0×10(-9)). Subgroup analysis according to ethnicity indicated an association between low FCGR3B CN and autoimmune diseases in Caucasians (OR=1.482, 95% CI=1.219-1.801, p=7.7×10(-6)) and Asians (OR=1.498, 95% CI=1.306-1.717, p=1.0×10(-9)). Meta-analysis according to the type of autoimmune disease indicated a significant association of low FCGR3B CN with systemic lupus erythematosus (SLE; OR=1.797, 95% CI=1.562-2.068, p<1.0×10(-9)), primary Sjogren's syndrome (pSS; OR=2.263, 95% CI=1.316-3.892, p=0.003), and Wegener's granulomatosis (WG; OR=1.973, 95% CI=1.178-3.302, p=0.010), but not with rheumatoid arthritis (RA; OR=1.333, 95% CI=0.947-1.877, p=0.099). However, the meta-analysis showed no association between high FCGR3B CN and SLE, RA, pSS, and WG. CONCLUSIONS: Thus, the results of this meta-analysis indicated that low FCGR3B CN increased susceptibility to autoimmune diseases, especially SLE, pSS, and WG.

Association between IL-6 -174 G/C, IL-6 -634 G/C, and IFN-γ +874 A/T polymorphisms and susceptibility to recurrent pregnancy loss: a meta-analysis.

OBJECTIVE: The aim of this study was to determine whether interleukin-6 (IL-6) -174 G/C, IL-6 -634 G/C, and interferon-γ (IFN-γ) +874 A/T polymorphisms are associated with susceptibility to recurrent pregnancy loss (RPL). METHODS: We conducted a literature search using PubMed and EMBASE databases and performed a meta-analysis using fixed- or random-effects models. RESULTS: A total of 15 articles met the study inclusion criteria. When all study subjects were considered together, meta-analysis showed no association between RPL and the IL-6 -174 GG + GC genotype (odds ratio [OR] = 0.794, 95 % confidence interval [CI] = 0.542-1.163, p = 0.236). However, stratification of the data by ethnicity indicated an association between this genotype and RPL in non-Caucasians (OR = 0.528, 95 % CI = 0.302-0.925, p = 0.028), but not in Caucasian populations. Moreover, meta-analysis revealed an association between RPL and the IL-6 -634 GG + GC genotype in all study subjects (OR = 0.556, 95 % CI = 0.383-0.806, p = 0.002), while stratification by ethnicity revealed a negative association between this genotype and RPL in Asian (OR = 0.545, 95 % CI = 0.371-0.800, p = 0.002) but not Middle Eastern populations. Furthermore, a relationship between the IFN-γ +874 A allele and RPL was identified in non-Caucasians (OR = 1.403, 95 % CI = 1.133-1.734, p = 0.002), but not in Caucasians. CONCLUSIONS: This meta-analysis demonstrates that IL-6 -174 G/C, IL-6 -634 G/C, and IFN-γ +874 A/T polymorphisms are associated with susceptibility to RPL, particularly in non-Caucasians.