Inflammasome-Related Genetic Polymorphisms as Severity Biomarkers of COVID-19.

The most critical forms of coronavirus disease 2019 (COVID-19) are associated with excessive activation of the inflammasome. Despite the COVID-19 impact on public health, we still do not fully understand the mechanisms by which the inflammatory response influences disease prognosis. Accordingly, we aimed to elucidate the role of polymorphisms in the key genes of the formation and signaling of the inflammasome as biomarkers of COVID-19 severity. For this purpose, a large and well-defined cohort of 377 COVID-19 patients with mild (n = 72), moderate (n = 84), severe (n = 100), and critical (n = 121) infections were included. A total of 24 polymorphisms located in inflammasome-related genes (NLRP3, NLRC4, NLRP1, CARD8, CASP1, IL1B, IL18, NFKB1, ATG16L1, and MIF) were genotyped in all of the patients and in the 192 healthy controls (HCs) (who were without COVID-19 at the time of and before the study) by RT-qPCR. Our results showed that patients with mild, moderate, severe, and critical COVID-19 presented similar allelic and genotypic distribution in all the variants studied. No statistically significant differences in the haplotypic distribution of NLRP3, NLRC4, NLRP1, CARD8, CASP1, IL1B, and ATG16L1 were observed between COVID-19 patients, who were stratified by disease severity. Each stratified group of patients presented a similar genetic distribution to the HCs. In conclusion, our results suggest that the inflammasome polymorphisms studied are not associated with the worsening of COVID-19.

Marcadores genéticos y séricos relacionados con una rápida progresión clínica de la arteriosclerosis coronaria / Serum and genetic markers related to rapid clinical progression of coronary artery disease

Introducción y objetivos: La progresión de la enfermedad coronaria una vez se hace evidente a la clínica tiene una gran variabilidad interindividual. El objetivo es determinar marcadores séricos y genéticos en pacientes con rápida progresión clínica (RPC) de la enfermedad coronaria frente a pacientes con estabilidad clínica mantenida (ECM). Métodos: Estudio retrospectivo de casos (RPC) y controles (ECM) (1:2). Se consideró RPC a los pacientes que precisaron al menos 2 revascularizaciones por progresión de la ateroesclerosis en los 10 años posteriores a una primera angioplastia y ECM a aquellos sin eventos durante el mismo periodo tras la primera angioplastia. Una vez seleccionados, se determinaron los valores séricos, la expresión de ácido ribonucleico mensajero (ARNm) y polimorfismos genéticos de interleucina 6, proteína C reactiva y factor de necrosis tumoral alfa (TNFα) como marcadores de inflamación y proproteína convertasa subtilisina/kexina tipo 9 (PCSK9), receptor de lipoproteínas de baja densidad, proteína 2 de unión a elementos reguladores de esteroles y apolipoproteína B como marcadores aterogénicos. Resultados: Se incluyó a 180 pacientes (58 en RPC y 122 en ECM). Las características basales demográficas, del perfil de riesgo clásico y de la extensión de la enfermedad coronaria fueron comparables. El grupo de RPC presentó valores séricos más altos de interleucina 6 y PCSK9 y mayor expresión de ARNm de TNF. Los alelos de Interleucina-6 rs180075C, de TNF rs3093664 non-G y de PCSK9 rs2483205 T confieren riesgo de RPC (p<0,05 en todos los casos). Un 51,7% de los pacientes del grupo RPC presentaron los tres alelos de riesgo frente al 18% de los pacientes del grupo en ECM (p<0,001). Conclusiones: Se propone la existencia de marcadores genotípicos y fenotípicos asociados con la RPC de enfermedad coronaria y que podrían servir para individualizar la intensidad y el tipo de tratamiento.(AU)

Introduction and objectives: Patients with clinically evident coronary artery disease differ in their rate of progression, which impacts prognosis. We aimed to characterize serum and genetic markers in patients with rapid clinical progression (RCP) of coronary artery disease vs those with long standing stable (LSS) disease. Methods: Retrospective study of cases (RCP) and controls (LSS) (1:2). Patients requiring ≥ 2 revascularizations due to atherosclerotic progression in the 10 years after a first angioplasty were considered to be RCP and those without events during the same period after the first angioplasty were considered to have LSS disease. After patient selection, we analyzed serum values, mRNA expression and genetic polymorphisms of inflammatory markers, including interleukin-6, C-reactive protein, and tumor necrosis factor (TNF)-a, and atherogenic markers consisted of proprotein convertase subtilisin/kexin type 9 (PCSK9), low-density lipoprotein receptor, sterol regulatory element binding transcription factor 2, and apolipoprotein-B. Results: The study included 180 patients (58 RCP and 122 LSS). Demographic characteristics, classic risk factors and the extent of coronary disease were similar in the 2 groups. Patients with RCP showed higher serum levels of interleukin-6 and PCSK9 and higher TNF mRNA expression. Interleukin-6 rs180075C, TNF rs3093664 non-G and PCSK9 rs2483205 T alleles conferred a risk of RCP (P<.05 in all cases). Among patients with RCP, 51.7% had all 3 risk alleles vs 18% of those with LSS (P<.001). Conclusions: We suggest the existence of specific phenotypic and genotypic markers associated with RCP of coronary artery disease that could help to individualize the type and intensity of treatment.(AU)

E-Selectin, ICAM-1, and ET-1 Biomarkers Address the Concern of the Challenging Diagnosis of Interstitial Lung Disease in Patients with Autoimmune Diseases.

Interstitial lung disease (ILD) constitutes the most critical comorbidity in autoimmune diseases (ADs) and its early diagnosis remains a challenge for clinicians. Accordingly, we evaluated whether E-selectin, ICAM-1, and ET-1, key molecules in endothelial damage, could be useful biomarkers for the detection of AD-ILD+. We recruited patients with rheumatoid arthritis (RA)-ILD+ (n = 21) and systemic sclerosis (SSc)-ILD+ (n = 21). We included comparison groups of patients: RA-ILD- (n = 25), SSc-ILD- (n = 20), and idiopathic pulmonary fibrosis (IPF) (n = 21). Serum levels of these proteins were determined by ELISA. E-selectin, ICAM-1, and ET-1 serum levels were increased in RA-ILD+ and IPF patients in comparison to RA-ILD- patients. Additionally, SSc-ILD+ and IPF patients exhibited higher ICAM-1 levels than those with SSc-ILD-. The ability of E-selectin, ICAM-1, and ET-1 to discriminate RA-ILD+ from RA-ILD- patients, and ICAM-1 to distinguish SSc-ILD+ from SSc-ILD- patients was confirmed using ROC curve analysis. Furthermore, elevated levels of ET-1 and E-selectin correlated with lung function decline in RA-ILD+ and SSc-ILD+ patients, respectively. In conclusion, our findings support the relevant role of E-selectin, ICAM-1, and ET-1 in RA-ILD+ patients as well as of ICAM-1 in SSc-ILD+ patients, constituting potential screening blood biomarkers of ILD in AD. Moreover, this study suggests ET-1 and E-selectin as possible indicators of worsening lung function in RA-ILD+ and SSc-ILD+ patients, respectively.

Serum and genetic markers related to rapid clinical progression of coronary artery disease.

INTRODUCTION AND OBJECTIVES: Patients with clinically evident coronary artery disease differ in their rate of progression, which impacts prognosis. We aimed to characterize serum and genetic markers in patients with rapid clinical progression (RCP) of coronary artery disease vs those with long standing stable (LSS) disease. METHODS: Retrospective study of cases (RCP) and controls (LSS) (1:2). Patients requiring ≥ 2 revascularizations due to atherosclerotic progression in the 10 years after a first angioplasty were considered to be RCP and those without events during the same period after the first angioplasty were considered to have LSS disease. After patient selection, we analyzed serum values, mRNA expression and genetic polymorphisms of inflammatory markers, including interleukin-6, C-reactive protein, and tumor necrosis factor (TNF)-a, and atherogenic markers consisted of proprotein convertase subtilisin/kexin type 9 (PCSK9), low-density lipoprotein receptor, sterol regulatory element binding transcription factor 2, and apolipoprotein-B. RESULTS: The study included 180 patients (58 RCP and 122 LSS). Demographic characteristics, classic risk factors and the extent of coronary disease were similar in the 2 groups. Patients with RCP showed higher serum levels of interleukin-6 and PCSK9 and higher TNF mRNA expression. Interleukin-6 rs180075C, TNF rs3093664 non-G and PCSK9 rs2483205 T alleles conferred a risk of RCP (P<.05 in all cases). Among patients with RCP, 51.7% had all 3 risk alleles vs 18% of those with LSS (P<.001). CONCLUSIONS: We suggest the existence of specific phenotypic and genotypic markers associated with RCP of coronary artery disease that could help to individualize the type and intensity of treatment.

Cranial and extracranial giant cell arteritis do not exhibit differences in the IL6 -174 G/C gene polymorphism.

OBJECTIVES: Since interleukin-6 (IL-6) is a pivotal proinflammatory cytokine implicated in the pathogenesis of giant cell arteritis (GCA), we aimed to determine the potential association of the functional IL6 -174 G/C polymorphism with GCA as well as if the single base change variation at the promoter region in the human IL-6 gene may account for differences in the clinical spectrum of GCA between cranial and extracranial large vessel vasculitis (LVV)-GCA. METHODS: The IL6 -174 G/C polymorphism (rs1800795) was genotyped in 191 patients with biopsy-proven GCA who had typical cranial manifestations of the disease, 109 patients with extracranial LVV-GCA, without cranial ischaemic manifestations of GCA, and 877 ethnically matched unaffected controls. A comparative study was carried out between patients with cranial and extracranial LVV-GCA and controls. RESULTS: No significant differences in genotype and allele frequencies of IL6 -174 G/C polymorphism were found between the whole cohort of GCA patients and healthy controls. It was also the case when cranial and extracranial LVV-GCA were compared or when each of these subgroups was compared to controls. Moreover, no significant results in genotype and allele frequencies of IL6 -174 G/C polymorphism were disclosed when the whole cohort of GCA patients were stratified according to the presence of polymyalgia rheumatica, severe ischaemic manifestations, including permanent visual loss and peripheral arteriopathy, and HLA-DRB1*04:01 status. CONCLUSIONS: Our results show that the IL6 -174 G/C polymorphism does not influence the phenotypic expression of GCA.

Endothelin-1 as a Biomarker of Idiopathic Pulmonary Fibrosis and Interstitial Lung Disease Associated with Autoimmune Diseases.

The aim of this study was to determine the role of endothelin-1 (ET-1), a molecule involved in multiple vascular and fibrosing abnormalities, as a biomarker of interstitial lung disease (ILD), as well as its use for the differential diagnosis between idiopathic pulmonary fibrosis (IPF) and ILD associated with autoimmune diseases (AD-ILD), using a large and well-defined cohort of patients with ILD. A total of 112 patients with IPF, 91 patients with AD-ILD (28 rheumatoid arthritis (RA), 26 systemic sclerosis, 20 idiopathic inflammatory myositis and 17 interstitial pneumonia with autoimmune features) and 44 healthy controls were included. ET-1 serum levels were determined by enzyme-linked immunosorbent assay. A significant increase in ET-1 levels was found in patients with IPF compared to controls. Likewise, AD-ILD patients also showed higher ET-1 levels than controls when the whole cohort was stratified by the type of AD. Similar ET-1 levels were found in IPF and AD-ILD patients, regardless of the underlying AD. Interestingly, increased ET-1 levels were correlated with worse lung function in IPF and RA-ILD patients. Our study supports that serum ET-1 may be useful as a biomarker of ILD, although it could not help in the differential diagnosis between IPF and AD-ILD. Moreover, ET-1 levels may be associated with ILD severity.

Cranial and extracranial large-vessel giant cell arteritis share a genetic pattern of interferon-gamma pathway.

OBJECTIVES: Two main different clinical phenotypes of giant cell arteritis (GCA) have been described, the classic cranial pattern and the extracranial large-vessel (LV) pattern. Since interferon gamma (IFNG) has shown to be a pivotal cytokine in the pathophysiology of GCA, our aim was to evaluate for the first time the influence of IFNG and IFNG receptor 1 (IFNGR1) polymorphisms in the different clinical phenotypes of GCA. METHODS: Two IFNG polymorphisms (rs2069718 G/A and rs1861493 A/G) and one polymorphism in IFNGR1 (rs1327474 G/A) were genotyped in 191 patients with biopsy-proven cranial GCA, 109 with extracranial LV-GCA and 490 healthy controls. A comparative study was conducted between patients with cranial and extracranial LV-GCA. RESULTS: No significant differences in genotype, allele, and haplotype frequencies of IFNG polymorphisms were found between GCA patients with the classic cranial pattern and the extracranial LV-GCA pattern. Similar results were found for genotype and allele frequencies of IFNGR1 polymorphism. It was also the case when patients with extracranial LV-GCA were compared with healthy controls. CONCLUSIONS: Our results show that IFNG and IFNGR1 polymorphisms do not influence the clinical phenotype of expression of GCA. Classic cranial GCA and extracranial LV-GCA seem to share a genetic pattern of IFNG pathway.

Serum leptin concentration is associated with the attainment of clinical outcomes in patients with axial spondyloarthritis treated with TNF inhibitors.

OBJECTIVES: To analyse the influence of adipokines on attaining the clinical outcomes in patients with axial spondyloarthritis (axSpA) treated with TNF inhibitors (TNFi), and then, to investigate the association of patients' characteristics and adipokine concentrations. METHODS: This was a longitudinal study including 110 patients with axSpA who were initiated at TNFi and were followed-up for 6 months (m). Disease activity was assessed by Ankylosing Spondylitis Disease Activity Score (ASDAS) at baseline and at 6 m of treatment. Clinical outcomes at 6 m of treatment were defined as remission (ASDAS <1.3) and the attainment of low disease activity (LDA; ASDAS<2.1). Leptin and adiponectin concentrations were measured in serum samples collected at baseline and after 6 m. RESULTS: Both leptin and adiponectin were constitutively elevated in female axSpA patients. At time of TNFi initiation, leptin concentrations were higher in patients with high body mass index (overweight or obese). On the contrary, adiponectin was higher in normalweight patients. After 6 m of TNFi treatment, 24% of patients attained remission. They had significant lower leptin concentration at baseline compared with patients who did not attain remission. Furthermore, this difference remained significant after 6 m of treatment meaning that TNFi did not modify adipokine concentration. Similar results were found considering LDA as the clinical outcome, obtained in 48% of the patients. CONCLUSIONS: The present study showed that low leptin concentrations were associated with attaining clinical outcomes in axSpA patients treated with TNFi. In addition, since leptin secretion by white adipocytes is enhanced during obesity and considering that TNFi do not seem to modulate its expression, obese patients should be encouraged to decrease BMI to attain a successful therapy.

A Proof-of-Concept Analysis of Plasma-Derived Exosomal microRNAs in Interstitial Pulmonary Fibrosis Secondary to Antisynthetase Syndrome.

Antisynthetase syndrome (ASSD) is an autoimmune disease characterized by the positivity of autoantibodies against different aminoacyl transfer RNA (tRNA) synthetases. Morbidity and mortality of this disease are highly affected by interstitial lung disease (ILD) which is present in about 80% of patients. In this study, we investigated possible differences in 84 immune-related circulating miRNAs between ASSD patients with and without ILD; we enrolled 15 ASSD patients, 11 with ILD (ILD+) and 4 without ILD (ILD-), and 5 patients with idiopathic pulmonary fibrosis (IPF) as an additional control group. All patients were at disease onset and not on therapy at the time of inclusion. Differentially expressed miRNAs were identified in plasma-derived exosomes, using an miRNA PCR array (MIHS-111ZG, Qiagen, Hilden, Germany); miR-30a-5p and miR-29c-3p were upregulated in ASSD-ILD patients compared to patients without lung involvement (adjusted p-value < 0.05). IPF patients showed higher miR-29c-3p expression levels with respect to both ASSD and ASSD-ILD (p = 0.0005), whereas levels of miR-30a-5p were not different. miR-29c-3p and miR-30a-5p are overexpressed in ASSD-ILD+ patients compared with ILD−. These miRNAs are involved in the regulation of inflammation and fibrosis through their action on NF-κB and TGF-ß1. Although the mechanistic role of these miRNAs in ASSD-ILD development has to be elucidated, we suggest that their exosome levels could be useful in identifying patients at risk of ILD.

IgA Vasculitis: Influence of CD40, BLK and BANK1 Gene Polymorphisms.

CD40, BLK and BANK1 genes involved in the development and signaling of B-cells are identified as susceptibility loci for numerous inflammatory diseases. Accordingly, we assessed the potential influence of CD40, BLK and BANK1 on the pathogenesis of immunoglobulin-A vasculitis (IgAV), predominantly a B-lymphocyte inflammatory condition. Three genetic variants within CD40 (rs1883832, rs1535045, rs4813003) and BLK (rs2254546, rs2736340, rs2618476) as well as two BANK1 polymorphisms (rs10516487, rs3733197), previously associated with inflammatory diseases, were genotyped in 382 Caucasian patients with IgAV and 955 sex- and ethnically matched healthy controls. No statistically significant differences were observed in the genotype and allele frequencies of CD40, BLK and BANK1 when IgAV patients and healthy controls were compared. Similar results were found when CD40, BLK and BANK1 genotypes or alleles frequencies were compared between patients with IgAV stratified according to the age at disease onset or to the presence/absence of gastrointestinal or renal manifestations. Moreover, no CD40, BLK and BANK1 haplotype differences were disclosed between patients with IgAV and healthy controls and between patients with IgAV stratified according to the clinical characteristics mentioned above. Our findings indicate that CD40, BLK and BANK1 do not contribute to the genetic background of IgAV.

Irisin as a Novel Biomarker of Subclinical Atherosclerosis, Cardiovascular Risk and Severe Disease in Axial Spondyloarthritis.

Introduction: Patients with axial spondyloarthritis (axSpA) have a high disease burden mainly due to the rheumatic disease itself, and also exhibit accelerated atherosclerosis, that leads to a higher incidence of cardiovascular (CV) disease. Accordingly, the identification of biomarkers of CV risk and inflammation in axSpA patients is clinically relevant. In this sense, given the beneficial functions exerted by the adipomyokine irisin in processes related to CV disease and inflammation, our aim was to assess, for the first time, the role of irisin as a genetic and serological biomarker of subclinical atherosclerosis, CV risk and disease severity in axSpA patients. Methods: A large cohort of 725 Spanish patients with axSpA was included. Subclinical atherosclerosis (presence of plaques and abnormal carotid intima-media thickness values) was evaluated by carotid ultrasound. Four irisin polymorphisms (rs16835198 G/T, rs3480 A/G, rs726344 G/A, and rs1570569 G/T) were genotyped by TaqMan probes. Additionally, serum irisin levels were determined by ELISA. Results: Low irisin levels were linked to the presence of plaques (p=0.002) and atherogenic index values ≥4 (p=0.01). Serum irisin were positively correlated with C-peptide levels (p<0.001) and negatively correlated with visual analogue scale and Bath Ankylosing Spondylitis Metrology Index (p<0.05 in all the cases). Moreover, lower irisin levels were observed in patients with sacroiliitis and in those with a negative HLA-B27 status (p<0.001 and p=0.006, respectively), as well as in those treated with non-steroidal anti-inflammatory drugs and conventional disease-modifying antirheumatic drugs (p<0.001 and p=0.002, respectively). Interestingly, the TT genotype and the T allele of rs16835198 were less frequent in axSpA patients with ASDAS >2.1 (Odds Ratio (OR): 0.48 [0.28-0.83] and OR: 0.73 [0.57-0.92], respectively, p=0.01 in both cases). Additionally, the frequency of rs1570569 T allele was higher in these patients (OR: 1.46 [1.08-1.97], p=0.01). Furthermore, the GGGT haplotype was more frequent in patients with ASDAS values >2.1 (OR: 1.73 [1.13-2.66], p=0.01). Conclusions: Our results indicate that low serum irisin levels could be indicators of the presence of subclinical atherosclerosis, high CV risk and more severe disease in axSpA patients. In addition, irisin may also constitute a genetic biomarker of disease activity in axSpA.

Angiogenic T Cells: Potential Biomarkers for the Early Diagnosis of Interstitial Lung Disease in Autoimmune Diseases?

(1) Background: We explored, for the first time, the contribution of angiogenic T cells (TAng) in interstitial lung disease associated to autoimmune disease (AD-ILD+) as potential biomarkers of the disease, evaluating their role in the underlying vasculopathy and lung fibrosis. Additionally, the relationship of TAng with clinical manifestations and cellular and molecular endothelial dysfunction-related biomarkers was assessed. (2) Methods: We included 57 AD-ILD+ patients (21 with rheumatoid arthritis (RA)-ILD+, 21 with systemic sclerosis (SSc)-ILD+ and 15 with other AD-ILD+) and three comparative groups: 45 AD-ILD- patients (25 RA-ILD- and 20 SSc-ILD-); 21 idiopathic pulmonary fibrosis (IPF) patients; 21 healthy controls (HC). TAng were considered as CD3+CD184+CD31+ by flow cytometry. (3) Results: A similar TAng frequency was found between AD-ILD+ and IPF, being in both cases lower than that observed in AD-ILD- and HC. A lower TAng frequency was associated with negative Scl-70 status and lower FEV1/FVC ratio in SSc-ILD+, as well as with men in RA-ILD+ and non-specific interstitial pneumonia radiological pattern in other AD-ILD+. No relationship between TAng and endothelial progenitor cells, endothelial cells and vascular endothelial growth factor gene expression and protein levels was disclosed. (4) Conclusions: Our findings suggest TAng as potential biomarkers for the early diagnosis of ILD in AD.

Epidemiological and genetic features of anti-3­hydroxy-3-methylglutaryl-CoA reductase necrotizing myopathy: Single-center experience and literature review.

OBJECTIVE: To characterize the demographic, genetic, clinical, and serological features of patients with anti-3­hydroxy-3-methylglutaryl-CoA reductase (HMGCR) immune-mediated necrotizing myopathy (IMNM) in a region of northern Spain. METHODS: Study of all patients diagnosed with anti-HMGCR IMNM during a 5-year period at a reference hospital in northern Spain. Besides clinical and laboratory data, we analyzed the genetic influence of HLA genes and the rs4149056 (c.521T>C) single nucleotide polymorphism (SNP) in the SLCO1B1 gene. RESULTS: 8 patients (5 women, 3 men) with a mean ± SD age of 64.9 ± 7.3 years, fulfilled the criteria for anti-HMGCR IMNM. The incidence rate was 0.6 per 100.000 person-years and the prevalence 3 per 100.000 population. All patients had been exposed to statins. All of them had predominant lower limb proximal and symmetric muscle weakness that was severe in 2 and had elevated serum CK levels with a median [IQR] of 4488 [2538-9194] IU/L. Serum 25­hydroxy vitamin D levels were decreased in all patients in whom it was determined. The 3 patients with a previous diagnosis of hypothyroidism had abnormal levels of TSH at the time of diagnosis. All patients experienced improvement with different schemes of immunosuppressive therapy. Noteworthy, 7 of 8 patients carried the HLA-DRB1*11 allele. The frequency of the rs4149056 C allele in the SLCO1B1 gene (12.5%) was similar to that of the general population. CONCLUSION: In northern Spain, anti-HMGCR IMNM preferentially affects people over 50 years of age who are carriers of the HLA-DRB1*11 allele and take statins. Both low vitamin D levels and hypothyroidism may play a potential predisposing role in the development of this disease.

Vascular endothelial growth factor haplotypes are associated with severe ischaemic complications in giant cell arteritis regardless of the disease phenotype.

OBJECTIVES: To determine whether functional vascular endothelial growth factor (VEGF) polymorphisms influence the expression of the clinical phenotype of giant cell arteritis (GCA). We also evaluated whether VEGF polymorphism is associated with the development of severe ischaemic manifestations in patients with GCA regardless of the clinical phenotype, classic cranial GCA or predominantly extracranial GCA large vessel vasculitis (LVV). METHODS: VEGF rs833061 T/C, rs2010963 G/C and rs3025039 C/T polymorphisms were genotyped in 185 patients with biopsy-proven cranial GCA, 105 with extracranial LVV-GCA and 490 healthy controls. Allelic combinations (haplotypes) of VEGF were carried out. Comparisons were performed between patients with GCA and healthy controls as well as between patients with GCA stratified according to the clinical phenotype and the presence of severe ischaemic manifestations. RESULTS: No significant differences in genotype, allele, and haplotype frequencies of VEGF were found between patients with GCA and healthy controls as well as between GCA patients with the classic cranial pattern and the extracranial LVV-GCA pattern of the disease. However, the VEGF CGC haplotype (OR= 1.63 [1.05-2.53]) and the CGT haplotype (OR= 2.55 [1.10-5.91]) were significantly more frequent in GCA patients with severe ischaemic complications compared to those patients without these complications. CONCLUSIONS: VEGF haplotypes seem to play a role in the development of severe ischaemic manifestations in GCA patients, regardless of the clinical phenotype of expression of the disease.

Obesity and response to biological therapy in rheumatoid arthritis: the role of body mass index and adipose tissue cytokines.

OBJECTIVES: To analyse the role of body mass index (BMI) in the clinical response to biologic dis-ease-modifying anti-rheumatic drugs (bDMARDs) in patients with rheumatoid arthritis (RA). To per-form an in-depth analysis of the pathophysiology of obesity by assessing serum adipokine levels and their potential changes according to treatment. METHODS: This study involved 105 patients with RA starting tumour necrosis factor inhibitors (TNFi) or tocilizumab (TCZ). Patients were classified ac-cording to BMI as normal-weight and overweight/obesity. The clinical response to treatment was as-sessed by Clinical Disease Activity Index (CDAI) 6 months after initiation of bDMARDs. Serum adi-pokines (leptin and adiponectin) were determined using a commercial immunoassay kit in samples ob-tained before initiation of bDMARDs and after 6 months of treatment. RESULTS: A correlation was observed between BMI and disease activity and between BMI and serum adipokines. Sixty percent of patients achieved low disease activity (LDA)/remission: 45 patients in TNFi group (64.2%) and 18 (51.4%) in TCZ group. In TNFi group, patients who did not attain LDA/remission had a higher BMI (kg/m2) ([28.7±5.1] vs. [24.5±4.6], p=0.001) and baseline CDAI (26.3 [17.4-33.9] vs. 19.8 [14.0-28.8], p<0.03). However, no differences in BMI or baseline CDAI were observed between patients who achieved LDA after 6 months in TCZ group. CONCLUSIONS: Obesity influences the extent of LDA/remission in patients treated with TNFi, but not in patients treated with TCZ, probably because of underlying pathophysiological mechanisms intrinsic to the production of proinflammatory adi-pokines. Therefore, therapeutic strategies with a mechanism of action other than TNF inhibition would be more suitable for obese patients.

Elevated VCAM-1, MCP-1 and ADMA serum levels related to pulmonary fibrosis of interstitial lung disease associated with rheumatoid arthritis.

Introduction: Early diagnosis of interstitial lung disease (ILD) associated with rheumatoid arthritis (RA) constitutes a challenge for the clinicians. Pulmonary vasculopathy is relevant in the development of interstitial lung disease. Accordingly, we aimed to explore the role of vascular cell adhesion molecule-1 (VCAM-1), monocyte chemoattractant protein-1 (MCP-1) and asymmetric dimethylarginine (ADMA), key molecules in the vasculopathy, as potential biomarkers of pulmonary fibrosis in RA-ILD+. Methods: We included 21 RA-ILD+ patients and two comparative groups: 25 RA-ILD- patients and 21 idiopathic pulmonary fibrosis (IPF) patients. Serum levels of the molecules were determined by ELISA, and mRNA expression was quantified by qPCR. Results: VCAM-1, MCP-1 and ADMA serum levels were increased in RA-ILD+ patients in relation to RA-ILD- and IPF patients. Additionally, RA-ILD+ patients exhibited increased CCL2 (gene encoding MCP-1) and decreased PRMT1 (gene related to ADMA synthesis) mRNA expression in relation to RA-ILD- patients. A lower expression of VCAM1, CCL2, and PRMT1 was observed in RA-ILD+ patients when compared with those with IPF. Furthermore, MCP-1 serum levels and PRMT1 mRNA expression were positively correlated with RA duration, and ADMA serum levels were positively associated with C-reactive protein in RA-ILD+ patients. Conclusion: Our study suggests that VCAM-1, MCP-1 and ADMA could be considered as useful biomarkers to identify ILD in RA patients, as well as to discriminate RA-ILD+ from IPF, contributing to the early diagnosis of RA-ILD+.

Role of adiponectin in non-diabetic patients with rheumatoid arthritis undergoing anti-IL-6 therapy.

OBJECTIVES: Adiponectin is an adipokine that plays a relevant role in the development of metabolic syndrome (MetS), a complication that increases the risk of cardiovascular (CV) disease in patients with rheumatoid arthritis (RA). Accordingly, we assessed for the first time the short-term effect of anti-IL-6 receptor tocilizumab (TCZ) administration on adiponectin serum levels in RA patients and explored the potential association of adiponectin levels with MetS features, other CV risk factors and demographic and clinical characteristics of these patients. METHODS: Adiponectin serum levels were evaluated in 50 non-diabetic RA patients, undergoing TCZ treatment, immediately prior to (pre-infusion) and 60 minutes after the end of a TCZ intravenous infusion (post-infusion). RESULTS: No significant differences in adiponectin levels pre- and post-TCZ infusion were found in RA patients (p=0.69). Patients with obesity exhibited decreased basal levels of adiponectin with respect to those non-obese (p=0.03). Additionally, a negative association of adiponectin basal levels with body mass index, insulin, insulin/glucose index, C-peptide and leptin levels (p<0.01; p=0.02; p=0.03; p=0.03 and p=0.01, respectively), as well as a positive correlation with HDL-cholesterol levels (p<0.001) was seen. CONCLUSIONS: Our results support the claim that low adiponectin may contribute to the development of MetS and, consequently, CV disease in RA. Anti-IL-6 therapy does not seem to exert a short-term effect on adiponectin levels.

Role of MUC1 rs4072037 polymorphism and serum KL-6 levels in patients with antisynthetase syndrome.

Mucin 1/Krebs von den Lungen-6 (KL-6) is proposed as a serum biomarker of several interstitial lung diseases (ILDs), including connective tissue disorders associated with ILD. However, it has not been studied in a large cohort of Caucasian antisynthetase syndrome (ASSD) patients. Consequently, we assessed the role of MUC1 rs4072037 and serum KL-6 levels as a potential biomarker of ASSD susceptibility and for the differential diagnosis between patients with ILD associated with ASSD (ASSD-ILD +) and idiopathic pulmonary fibrosis (IPF). 168 ASSD patients (149 ASSD-ILD +), 174 IPF patients and 523 healthy controls were genotyped for MUC1 rs4072037 T > C. Serum KL-6 levels were determined in a subgroup of individuals. A significant increase of MUC1 rs4072037 CC genotype and C allele frequencies was observed in ASSD patients compared to healthy controls. Likewise, MUC1 rs4072037 TC and CC genotypes and C allele frequencies were significantly different between ASSD-ILD+ and IPF patients. Additionally, serum KL-6 levels were significantly higher in ASSD patients compared to healthy controls. Nevertheless, no differences in serum KL-6 levels were found between ASSD-ILD+ and IPF patients. Our results suggest that the presence of MUC1 rs4072037 C allele increases the risk of ASSD and it could be a useful genetic biomarker for the differential diagnosis between ASSD-ILD+ and IPF patients.

Endothelial Progenitor Cells: Relevant Players in the Vasculopathy and Lung Fibrosis Associated with the Presence of Interstitial Lung Disease in Systemic Sclerosis Patients.

Endothelial progenitor cells (EPC), which are key effectors in the physiologic vascular network, have been described as relevant players in autoimmune diseases. We previously showed that EPC frequency may help to identify the presence of interstitial lung disease (ILD) in rheumatoid arthritis patients. Given that ILD constitutes the main cause of mortality in systemic sclerosis (SSc) patients, we aimed to determine the EPC contribution to the pathogenic processes of vasculopathy and lung fibrosis in SSc-ILD+. EPC quantification was performed by flow cytometry on blood from 83 individuals: 21 SSc-ILD+ patients and subjects from comparative groups (20 SSc-ILD- and 21 idiopathic pulmonary fibrosis (IPF) patients and 21 healthy controls (HC)). EPC were considered as CD34+, CD45low, CD309+, and CD133+. A significant increase in EPC frequency was found in SSc-ILD+ patients when compared to HC (p < 0.001). SSc-ILD+ patients exhibited a higher EPC frequency than SSc-ILD- patients (p = 0.012), whereas it was markedly reduced compared to IPF patients (p < 0.001). EPC frequency was higher in males (p = 0.04) and negatively correlated to SSc duration (p = 0.04) in SSc-ILD+ patients. Our results indicate a role of EPC in the processes of vasculopathy and lung fibrosis in SSc-ILD+. EPC frequency may be considered as a biomarker of ILD in SSc patients.