Rheumatoid Arthritis Patients With Circulating Extracellular Vesicles Positive for IgM Rheumatoid Factor Have Higher Disease Activity

Rheumatoid arthritis (RA) is an autoimmune inflammatory disease that mainly affects synovial joints. Validated laboratory parameters for RA diagnosis are higher blood levels of rheumatoid factor IgM (IgM-RF), anti-citrullinated protein autoantibodies (ACPA), C-reactive protein (CRP) levels and erythrocyte sedimentation rate (ESR). Clinical parameters used are the number of tender (TJC) and swollen joints (SJC) and the global patient visual analog score (VAS). To determine disease remission in patients a disease activity score (DAS28) can be calculated based on SJC, TJC, VAS, and ESR (or alternatively CRP). However, subtle and better predictive changes to follow treatment responses in individual patients cannot be measured by the above mentioned parameters nor by measuring cytokine levels in blood. As extracellular vesicles (EVs) play a role in intercellular communication and carry a multitude of signals we set out to determine their value as a biomarker for disease activity. EVs were isolated from platelet-free plasma of 41 RA patients and 24 healthy controls (HC) by size exclusion chromatography (SEC). We quantified the particle and protein concentration, using NanoSight particle tracking analysis and micro-BCA, respectively, and observed no differences between RA patients and HC. In plasma of 28 out of 41 RA patients IgM-RF was detectable by ELISA, and in 13 out of these 28 seropositive RA patients (RF+RA) IgM-RF was also detected on their isolated pEVs (IgM-RF+). In seronegative RA patients (RF−RA) we did not find any RF present on pEVs. When comparing disease parameters we found no differences between RF+RA and RF−RA patients, except for increased ESR levels in RF+RA patients. However, RF+RA patients with IgM-RF+ pEVs showed significantly higher levels of CRP and ESR and also VAS and DAS28 were significantly increased compared to RA+ patients without IgM-RF+ pEVs. This study shows for the first time the presence of IgM-RF on pEVs in a proportion of RF+RA patients with a higher disease activity

IL-1β-Mediated Activation of Adipose-Derived Mesenchymal Stromal Cells Results in PMN Reallocation and Enhanced Phagocytosis: A Possible Mechanism for the Reduction of Osteoarthritis Pathology

Background: Injection of adipose-derived mesenchymal stromal cells (ASCs) into murine knee joints after induction of inflammatory collagenase-induced osteoarthritis (CiOA) reduces development of joint pathology. This protection is only achieved when ASCs are applied in early CiOA, which is characterized by synovitis and high S100A8/A9 and IL-1β levels, suggesting that inflammation is a prerequisite for the protective effect of ASCs. Our objective was to gain more insight into the interplay between synovitis and ASC-mediated amelioration of CiOA pathology.Methods: CiOA was induced by intra-articular collagenase injection. Knee joint sections were stained with hematoxylin/eosin and immunolocalization of polymorphonuclear cells (PMNs) and ASCs was performed using antibodies for NIMP-R14 and CD271, respectively. Chemokine expression induced by IL-1β or S100A8/A9 was assessed with qPCR and Luminex. ASC-PMN co-cultures were analyzed microscopically and with Luminex for inflammatory mediators. Migration of PMNs through transwell membranes toward conditioned medium of non-stimulated ASCs (ASCNS-CM) or IL-1β-stimulated ASCs (ASCIL-1β-CM) was examined using flow cytometry. Phagocytic capacity of PMNs was measured with labeled zymosan particles.Results: Intra-articular saline injection on day 7 of CiOA increased synovitis after 6 h, characterized by PMNs scattered throughout the joint cavity and the synovium. ASC injection resulted in comparable numbers of PMNs which clustered around ASCs in close interaction with the synovial lining. IL-1β-stimulation of ASCs in vitro strongly increased expression of PMN-attracting chemokines CXCL5, CXCL7, and KC, whereas S100A8/A9-stimulation did not. In agreement, the number of clustered PMNs per ASC was significantly increased after 6 h of co-culturing with IL-1β-stimulated ASCs. Also migration of PMNs toward ASCIL-1β-CM was significantly enhanced (287%) when compared to ASCNS-CM. Interestingly, association of PMNs with ASCs significantly diminished KC protein release by ASCs (69% lower after 24 h), accompanied by reduced release of S100A8/A9 protein by the PMNs. Moreover, phagocytic capacity of PMNs was strongly enhanced after priming with ASCIL-1β-CM.Conclusions: Local application of ASCs in inflamed CiOA knee joints results in clustering of attracted PMNs with ASCs in the synovium, which is likely mediated by IL-1β-induced up-regulation of chemokine release by ASCs. This results in enhanced phagocytic capacity of PMNs, enabling the clearance of debris to attenuate synovitis

Organização do trabalho de enfermagem na Atenção Básica: uma questão para a saúde do trabalhador

Contains fulltext : 208073.pdf (publisher's version ) (Open Access

New insights into the genetic etiology of Alzheimer's disease and related dementias

Characterization of the genetic landscape of Alzheimer's disease (AD) and related dementias (ADD) provides a unique opportunity for a better understanding of the associated pathophysiological processes. We performed a two-stage genome-wide association study totaling 111,326 clinically diagnosed/'proxy' AD cases and 677,663 controls. We found 75 risk loci, of which 42 were new at the time of analysis. Pathway enrichment analyses confirmed the involvement of amyloid/tau pathways and highlighted microglia implication. Gene prioritization in the new loci identified 31 genes that were suggestive of new genetically associated processes, including the tumor necrosis factor alpha pathway through the linear ubiquitin chain assembly complex. We also built a new genetic risk score associated with the risk of future AD/dementia or progression from mild cognitive impairment to AD/dementia. The improvement in prediction led to a 1.6- to 1.9-fold increase in AD risk from the lowest to the highest decile, in addition to effects of age and the APOE ε4 allele

The Prospective Dutch Colorectal Cancer (PLCRC) cohort: real-world data facilitating research and clinical care

Real-world data (RWD) sources are important to advance clinical oncology research and evaluate treatments in daily practice. Since 2013, the Prospective Dutch Colorectal Cancer (PLCRC) cohort, linked to the Netherlands Cancer Registry, serves as an infrastructure for scientific research collecting additional patient-reported outcomes (PRO) and biospecimens. Here we report on cohort developments and investigate to what extent PLCRC reflects the “real-world”. Clinical and demographic characteristics of PLCRC participants were compared with the general Dutch CRC population (n = 74,692, Dutch-ref). To study representativeness, standardized differences between PLCRC and Dutch-ref were calculated, and logistic regression models were evaluated on their ability to distinguish cohort participants from the Dutch-ref (AU-ROC 0.5 = preferred, implying participation independent of patient characteristics). Stratified analyses by stage and time-period (2013–2016 and 2017–Aug 2019) were performed to study the evolution towards RWD. In August 2019, 5744 patients were enrolled. Enrollment increased steeply, from 129 participants (1 hospital) in 2013 to 2136 (50 of 75 Dutch hospitals) in 2018. Low AU-ROC (0.65, 95% CI: 0.64–0.65) indicates limited ability to distinguish cohort participants from the Dutch-ref. Characteristics that remained imbalanced in the period 2017–Aug’19 compared with the Dutch-ref were age (65.0 years in PLCRC, 69.3 in the Dutch-ref) and tumor stage (40% stage-III in PLCRC, 30% in the Dutch-ref). PLCRC approaches to represent the Dutch CRC population and will ultimately meet the current demand for high-quality RWD. Efforts are ongoing to improve multidisciplinary recruitment which will further enhance PLCRC’s representativeness and its contribution to a learning healthcare system

Tyro3/Axl/Mertk-deficient mice develop bone marrow edema which is an early pathological marker in rheumatoid arthritis.

Rheumatoid arthritis is an auto-immune disease of the synovial joints, hallmarked by chronic inflammation and subsequent progressive tissue destruction. TYRO3, AXL and MER (gene name Mertk) (TAM) receptors are part of a negative feedback signaling system in the immune reaction and mediate efferocytosis thereby tempering the inflammatory process. We have shown that Axl-/- and Mertk-/- mice develop more severe arthritis whereas activating these receptors by overexpressing their ligands Pros1 and Gas6 ameliorates arthritis. Mice genetically ablated for the three genes of the TAM receptor family Tyro3/Axl/Mertk (TAM triple knock-out or TKO) have been described to spontaneously develop macroscopic signs of arthritis. In this study we aimed to analyze arthritis development in TAM TKO mice histologically to determine the extent and sequence of pathological changes in the joint. Ankle joints of three different age groups, adolescence (14 weeks), mature adult (34 weeks) and middle-age (52 weeks), of TAM TKO or wild-type mice were examined macroscopically, histologically and immunohistochemically. Surprisingly, until the age of 52 weeks, none of the mice examined developed spontaneous macroscopic signs of arthritis. There was no synovial inflammation nor any signs of damage to the cartilage or bone. However, bone marrow edema was observed in TAM TKO mice in the two latter age groups. The infiltrate in the bone marrow was characterized by both myeloid cells and lymphocytes. This study showed that TAM TKO mice developed a pre-stage (pre-clinical phase) of arthritis marked by bone marrow edema

Selective Increment of Synovial Soluble TYRO3 Correlates with Disease Severity and Joint Inflammation in Patients with Rheumatoid Arthritis

Objective. To investigate the role of TAM receptors in rheumatoid arthritis (RA) by determining synovial tissue TAM receptor expression, synovial fluid levels of soluble TAM receptors, and the relationship between soluble TAM receptors, joint inflammation and disease activity. Methods. TAM receptor expression was determined by immunohistochemistry on the synovium from RA and osteoarthritis (OA) patients. Soluble (s) Tyro3, sAxl, sMer, and their ligand Gas6 were measured by ELISA in the synovial fluid of RA (n=28) and OA (n=12) patients and cytokine levels by multiplex immunoassay in RA samples. Correlation analyses were performed among sTAM receptors with local cytokine levels; systemic disease parameters like erythrocyte sedimentation rate (ESR), rheumatoid factor (RF), and anticyclic citrullinated peptide antibodies (ACPA); and disease activity scores (DAS28-ESR) in RA patients. Results. TAM receptors were expressed on different locations in the synovial tissue (lining, sublining, and blood vessels), and a similar expression pattern was observed in RA and OA patients. Synovial fluid sTyro3 and sMer were significantly enhanced in RA compared to OA patients, whereas no significant differences in sAxl and Gas6 levels were found. In RA samples, sTyro3 levels, but not sMer, correlated positively with proinflammatory local cytokines and the systemic factor erythrocyte sedimentation rate. Moreover, stratification analysis showed high sTyro3 levels positively correlated with higher DAS28-ESR and in RF and ACPA double positive RA patients. Conclusion. sTyro3 in the synovial fluid of RA patients correlates with local inflammatory molecules and systemic disease activity. These findings suggest that the reduced negative control of cell activation by TAM receptors due to their shedding in the synovial fluid, mainly sTyro3, favoring joint inflammation in RA patients