The inflammatory arthritis Ankylosing Spondylitis (AS) is linked to the human leucocyte antigen HLA-B27. HLA-B27 is thought to drive AS because it misfolds during assembly in the endoplasmic reticulum (ER), inducing ER cell stress. Modulating HLA-B27 folding in the ER is therefore a therapeutic target pathway. The recent discovery of polymorphisms in the ER-resident peptidase ERAP1 that can impact on HLA-B27 and AS, makes ERAP1 one such target. Exosomes are small, typically 50-200 nm sized particles, formed in the endosomal recycling pathway, which can be released into the extracellular environment. Exosomes have a wide range of biological activities depending on the cell type of origin, and on the delivered cargo, which can include bio-active proteins, lipids, mRNA and miRNA. There is interest in the use of exosomes as drug delivery agents. Here, exosomes were studied as a delivery agent to modulate ERAP1, as a potential therapeutic tool for the treatment of AS. Exosomes, isolated from cell lines including CEM and Jurkat (T cell lineage), Jesthom (B cell lineage), U937 (monocyte lineage) and the epithelial HeLa cell line, were characterized by nanoparticle tracking analysis, flow cytometry and immunoblotting using markers including CD9, CD63, CD81 and TSG101. Differential expression of these markers in the immune cell lines indicated the complexity of defining exosomes. EVs were then tested using cell penetrating peptides, electroporation, lipid transfection and sonication for their ability to load FITC-siRNA or FITC-antibody as cargo. Significantly, post-loading RNase A or trypsin incubation demonstrated that many techniques do not lead to efficient cargo loading of exosomes. Sonication proved the most effective technique, with up to 30% efficiency. Loading of exosomes with ERAP1-targetted siRNA did not however lead to notable ERAP1 inhibition. The data indicates that external loading of exosomes with cargo remains a significant challenge in developing exosomes as therapeutic tools.

Made available in DSpace on 2014-12-17T14:13:47Z (GMT). No. of bitstreams: 1 ElianeMS_DISSERT.pdf: 1308169 bytes, checksum: b8d50e23c9e0ac50c9a3012fb88a87b4 (MD5) Previous issue date: 2010-04-20 / Universidade Estadual do Rio Grande do Norte / The Ankylosing Spondylitis (AS) is a chronic inflammatory disease that primarily affects the axial skeleton, leading to limitation of spine mobility and functional disability. Physical therapy, especially exercise, is an important part in your treatment. The Global Postural Reeducation(GPR),a method that uses stretching based on evaluation of muscular chains, with significant interference in postural changes may be a complementary alternative for the treatment of this disease. The aim was to evaluate the effects of Global Postural Reeducation (GPR) in patients with Ankylosing Spondylitis (AS) and compare GPR with group conventional segmental self-stretching and breathing exercises. This is a controlled interventional study of 38 patients divided into 2 groups: a GPR group (n = 22) and a control group (n = 16). Both groups were treated over four months. With the GPR group patients, positions that stretched the shortened muscle chains were used. With the control group patients, conventional segmental self-stretching and breathing exercises were performed. The variables analyzed were: pain intensity, morning stiffness, spine mobility, chest expansion, functional capacity (Health Assessment Questionnaire - Spondyloarthropathies - HAQ-S), quality of life (Medical Outcome Study Short Form 36 Healthy Survey-SF-36), and disease activity (Bath Ankylosing Spondylitis Disease Activity Index - BASDAI). Statistical analysis was used with a significance level of p < 0.05. There was a statistically significant difference for all the parameters analyzed between pre and post-treatment in both groups. In the inter-group comparison the GPR group showed a statistically significant improvement in morning stiffness (p = 0.01), spine mobility parameters, except finger-floor distance (p = 0.11), in chest expansion (p = 0.02), and in the physical aspect component of the SF-36 (p = 0.00).Finally, we observed that this sample of patients with AS ,treatment with RPG 60 seems to have a better response in some clinical measures, than the conventional self stretching performed in groups. Further studies are needed to further evaluate this therapeutic alternative in the EA / A Espondilite Anquilosante (EA) ? uma doen?a inflamat?ria cr?nica que acomete principalmente o esqueleto axial, levando ? limita??o da mobilidade da coluna e incapacidade funcional. A fisioterapia, particularmente a cinesioterapia, ? parte importante no seu tratamento. A Reeduca??o Postural Global (RPG), um m?todo que utiliza alongamento baseado em avalia??o de cadeias musculares, com interfer?ncia importante nas altera??es posturais, poder? ser uma alternativa complementar no tratamento dessa doen?a. O objetivo deste estudo foi avaliar os efeitos da RPG individual em pacientes com EA e comparar com um programa de auto alongamento convencional e exerc?cios respirat?rios, feitos em grupo. Trata-se de um estudo intervencional controlado, totalizando 38 pacientes com EA, divididos em dois grupos, tratados durante quatro meses: o grupo RPG (n=22) e o grupo controle (n=16). O grupo RPG realizou posturas de alongamento das cadeias musculares e o grupo controle realizou auto- alongamento convencional e exerc?cios respirat?rios em grupo. As vari?veis analisadas foram: intensidade da dor, dura??o da rigidez matinal, mobilidade da coluna, expansibilidade tor?cica, atividade da doen?a (Bath Ankylosing Spondylitis Disease Activity ?ndex-BASDAI), capacidade funcional (Health Assessment Questionnaire- Spondyloarthropathies-HAQ-S) e qualidade de vida (Medical Outcome Study Short Form 36 Healthy Survey-SF-36). Para a an?lise dos dados foi utilizada um n?vel de signific?ncia de p < 0.05. Os resultados mostraram que houve uma diferen?a estatisticamente significante, em todos os par?metros analisados, em ambos os grupos entre o pr? e p?s- tratamento. xiv Em compara??o ao grupo controle, o grupo RPG mostrou melhora estatisticamente significante na rigidez matinal (p=0.01), nos par?metros da mobilidade da coluna (exceto dist?ncia dedo-ch?o (p=0.11)), na expansibilidade tor?cica (p=0.02) e no componente Aspecto F?sico do SF-36 (p=0.00). Ao final, observamos que, nesta amostra de pacientes com EA, o tratamento com RPG parece ter uma resposta melhor em algumas medidas cl?nicas, do que o auto- alongamento convencional, realizado em grupo. Outros estudos s?o necess?rios para melhor avaliar esta alternativa terap?utica na EA

The number of rheumatic diseases has been increasing in Europe. It is estimated that currently up to a quarter of Europeans suffer from some type of rheumatism. Rheumatoid arthritis and Bechterew's disease (ankylosing spondylitis) are chronic diseases manifested by pain, stiffness, inflammation of joints and the back. The theoretical section is divided into two parts; the first part defines rheumatoid arthritis and Bechterew's disease from the health point of view. The second part is devoted to the social area that is often neglected. The aim of the practical section of the thesis is to reveal how rheumatoid arthritis differs from Bechterew's disease in terms of the use of social assistance, as well as employability or participation in social life. For the data collection, qualitative research methods and interviewing techniques were used. The addressed respondents were patients of rheumatology consulting rooms of the Medipont Plus Ltd., who were divided into two groups ? patients with rheumatoid arthritis and those with Bechterew's disease. The research has shown that persons suffering form rheumatoid arthritis are more likely to get a disability pension than those with Bechterew's disease and they also more often use social contributions, most frequently the extra benefits for people with disabilities ? ZTP cards. This is related to a lower work capability in patients with rheumatoid arthritis compared to those with Bechterew's disease. The research results are influenced by the age of the respondents, the length of the illness, the difference in the roles of men and women and last but not least, by personality characteristics. The research has proved that patients suffering from rheumatic diseases as well as those suffering from Bechterew's disease and undergoing biological treatment are more self-sufficient due to this modern treatment. It has also been found that the respondents who are not fully self-sufficient are not informed about the possibilities to get social benefits and contributions and do not know where to get this information. The thesis could provide an impetus for the strategy when rheumatic diseases are not considered only a medical issue, because these diseases significantly influence the lives of the people affected and thus become a serious psychosocial issue.

No description available.

published_or_final_version / Social Work / Master / Master of Social Work

The MHC class I allele, HLA-B27, is strongly associated with a group of inflammatory arthritic conditions collectively known as spondyloarthropathies (SpA). Ankylosing spondylitis (AS) shows the strongest association with 90-95 % of patients being HLA-B27 positive. The relationship between HLA-B27 and SpA has been known for over 30 years, however despite ongoing research, the reason for this association has not yet been elucidated. In more recent years, research has focused on intrinsic properties of the HLA-B27 allele, in particular its propensity to misfold, forming homodimers. It has been proposed that these homodimers could be associated with the disease process through the activation of an ER stress response known as the unfolded protein response (UPR), or through aberrant recognition at the cell surface. We have investigated whether the expression of HLA-B27 is associated with the activation of the UPR. We have studied the expression of BiP, and the cleavage of XBP1 and ATF6 using stable and transiently expressing cell lines. We have also investigated the formation of non-B27 homodimers using a human cell line stably expressing HLA-B8, and finally we have studied the expression of homodimers in exosomes, small immunomodulatory vesicles released from numerous cell types. The results presented here lead us to conclude that in vitro studies of the UPR are complicated, prone to a number of technical issues, and may therefore not be appropriate for gaining information that would be of significant use when comparing to the real disease scenario. Our data suggest that non-B27 dimers may be strongly influenced by both the overexpression of MHC class I heavy chains and also the redox environment within the cell. We have isolated a novel fully folded, beta-2m-associated, MHC class I homodimer in exosomes and have detected a novel HLA-A and HLA-B mixed heavy chain dimer. Our results suggest that these dimers form through interactions between the cysteine residues in the cytoplasmic tail and that these dimers form in exosomes because they contain lower levels of the important antioxidant glutathione when compared to whole cells. Together, these results define a new MHC class I structure present on exosomes at significant levels, which could potentially influence immune recognition by both antigen-specific T cell receptors and NK family receptors. The data also poses questions about whether these novel structures, when they involve HLA-B27, could influence the pathogenesis of spondyloarthropathies.

The Major Histocompatibility Complex (MHC) is a genomic region in chromosome 6 which has been consistently found to be associated with the risk of developing virtually all common autoimmune diseases. Although its importance in disease pathogenesis has been known for decades, efforts to disentangle the roles of the classical human leukocyte antigens (HLA) and other variants responsible for the susceptibility to disease have often met with limited success, owing to the complex structure and extreme heterogeneity of the region. In this thesis, I interrogate the MHC for association with three common autoimmune diseases, ankylosing spondylitis, psoriasis and multiple sclerosis, with the aim of confirming the previously-reported associations and of identifying novel ones. To do so, I employ a systematic, joint analysis of single nucleotide polymorphism (SNP) and HLA allele data, in a logistic regression framework, using a recently developed algorithm to predict the HLA alleles for samples where such information is unavailable. To ensure the reliability of the analysis, I apply stringent quality control procedures and integrate over the uncertainty of the HLA allele predictions. Moreover, I resolve the haplotype phase of individuals from the HapMap project to create reliable reference panels, used in both HLA prediction and in quality control procedures. By directly testing HLA subtypes for association with the disease, the power to detect such associations is increased. I present the results of the analysis on the three disease phenotypes and discuss the evidence for important novel findings amongst both SNPs and HLA alleles in two of the diseases. In the final part of this thesis, I introduce a novel, model-based approach to detect inconsistencies in the data and show how it can be used to flag problematic SNPs which conventional quality control procedures may fail to identify.

Die axiale Spondyloarthritis (axSpA) ist eine chronische entzündlich-rheumatische Erkrankung unbekannter Ursache, die durch Entzündungen in den Sakroiliakalgelenken (SIG) und an den Gelenken der Wirbelsäule gekennzeichnet ist. Darüber hinaus kann es im Krankheitsverlauf zu einer Ankylose in den SIG und zur Entwicklung von Syndesmophyten an den Wirbelkörpern kommen. Da ein Großteil der axSpA-Patienten auch sub-klinische mukosale Entzündungen aufweist, werden mukosale Antigene als Trigger der Entzündung diskutiert. Für die Diagnose und Prognose der axSpA existieren bisher wenige serologische Marker mit hoher Sensitivität. In dieser Arbeit konnte gezeigt werden, dass die Serumkonzentrationen von CTX-II, BMP-2 und LBP ein hohes diagnostisches Potenzial für die axSpA aufweisen, während die Serumkonzentrationen von BMP-2, PINP und VEGF als Marker für die Vorhersage röntgenolgischer Progression geeignet sein könnten. Weiterhin konnten erhöhte LPS-, LBP- und IL-6-Serum-Konzentrationen bei axSpA-Patienten nachgewiesen werden, die auf eine Translokation bakterieller Antigene hinweisen. Die Charakterisierung der Monoyzten zeigte erhöhte Frequenzen der CD14++CD16- und einen verminderten Anteil an CD14++CD16+ Monozyten in Patienten mit axSpA. Funktionell wiesen die Monozyten von axSpA-Patienten eine in vivo Präaktivierung mit erhöhter spontaner und durch suboptimale bakterielle Stimuli induzierter Freisetzung proinflammatorischer Zytokine bei gleichzeitig verminderter Reaktivität auf LPS in vitro auf. Diese Präaktivierung war bei Patienten unter Standardtherapie, nicht aber unter TNF-Blocker-Therapie, nachweisbar. Interessanterweise bestand bei Patienten unter Standardtherapie ein Zusammenhang zwischen der Krankheitsaktivität und der Frequenz zytokinproduzierender Monozyten. Somit konnten mit dieser Arbeit Biomarker mit diagnostischer und prognostischer Bedeutung für die axSpA identifiziert werden, deren Bedeutung in unabhängigen Kohorten weiter untersucht werden muss. / Axial Spondyloarthitis (axSpA) is a chronic inflammatory-rheumatic disease of unknown cause. It is characterized by inflammations of the sacroiliac joints (SIG) and the spinal joints. In addition an ankylosis in the SIG can develop in the progression of the disease as well as syndesmophytes at the vertebral body. Since the majority of axSpA-patients also have sub-clinical mucosal inflammations, mucosal anti-gens are discussed as triggers of the inflammation. For the diagnosis and prognosis of axSpA there are only a few serological markers with high sensitivity and specificity until now. In this thesis it could be shown that the serum concentration of CTX-II, BMP-2 and LBP exhibit a high diagnostic potential for axSpA, while the serum concentration of BMP-2, PINP and VEGF could be suitable markers for the forecast of radiographic progression. Furthermore increased LPS-, LBP- and IL-6-serum concentrations could be verified, which can be an indicator for the translocation of bacterial antigenes. The monocyte characterization showed increased frequencies of the pro-inflammatory CD14++CD16- sub population and a reduced portion of CD14++CD16+ monocytes in patients with axSpA. Functionally the monocytes of axSpA-patients showed an in vivo pre-activation with increased spontaneous and by suboptimal bacterial stimuli induced release of pro-inflammatory cytokines with simultaneously reduced reactivity towards LPS in vitro. This pre-activation could be detected for patients undergoing standard therapy, but not for those under TNF-blocker-therapy. Interestingly for the standard therapy patients there was a connection between the activity of the disease, meaning the BASDAI, and the frequency of the cytokine-producing monocytes. Therefore biomarkers with diagnostic and prognostic relevance could be identified in line with this thesis. The significance of these biomarkers has to be researched further in independent cohorts.

Introdução: Baixas concentrações séricas de esclerostina foram descritas em pacientes com Espondilite Anquilosante (EA). No entanto, não existem dados sobre a importância deste inibidor da via de sinalização Wnt em pacientes com EA durante o tratamento com anti fator de necrose tumoral alfa (TNFa). Objetivos: Avaliar longitudinalmente os níveis séricos de esclerostina e sua associação com inflamação e densidade mineral óssea (DMO) em pacientes com EA em tratamento com anti-TNFa. Métodos: Trinta pacientes com EA em atividade foram avaliados no início, 6 e 12 meses, após terapia anti-TNFa em relação aos parâmetros clínicos (BASDAI, BASFI, BASMI e ASQoL), marcadores inflamatórios e dano radiológico basal (mSASSS). Trinta indivíduos saudáveis pareados por idade e sexo constituíram o grupo controle. As análises laboratoriais de esclerostina e da ligação de esclerostina ao receptor LRP6 e a DMO foram realizadas nos pacientes nos mesmos períodos de avaliação e comparadas aos controles. Resultados: Na avaliação inicial, pacientes com EA apresentavam menores concentrações séricas de esclerostina [60,5 (32,7) vs. 96,7 (52,9) pmol/l,P=0,002] e níveis similares de ligação de esclerostina ao receptor LRP6 (P=0,387) em relação aos controles. Foi observado melhora do BASDAI, BASFI, BASMI, ASQoL comparando tempo basal vs. 6 vs. 12 meses (P<0,01). Concomitantemente, observou-se um aumento gradual da DMO da coluna lombar (P<0,001) e no início do estudo os pacientes apresentavam uma correlação positiva entre avaliação radiológica basal (mSASSS) e a DMO da coluna lombar (r=0,468, P<0,01). Foi observada também uma redução dos marcadores inflamatórios comparando tempo basal vs. 6 vs. 12 meses (P<0,01). Os níveis de esclerostina aumentaram progressivamente após o tratamento com anti-TNFa [60,5 (32,7) vs. 67,1 (31,9) vs. 72,7 (32,3) pmol/l, P<0,001]. Entretanto, após 12 meses de terapia anti-TNFa as concentrações séricas de esclerostina permaneceram significativamente mais baixos em relação os controles [72,7 (32,3) vs. 96,7 (52,9) pmol/l, P=0,038]. Além disso, aos 12 meses, os níveis séricos de esclerostina ficaram mais baixos nos 10 pacientes que ainda apresentavam proteína C reativa elevada (PCR=5mg/l), comparados aos pacientes que apresentaram normalização dos níveis de PCR (P=0,004). Interessantemente, estes 10 pacientes com inflamação persistente já apresentavam concentrações séricas mais baixas de esclerostina quando comparados aos demais pacientes (P=0,023) antes do tratamento com anti- TNFa. A análise de regressão logística demonstrou que os pacientes com EA com níveis baixos de esclerostina apresentam um risco aumentado de apresentar PCR alta após 12 meses de tratamento (odds ratio = 7,43, 95% IC 1,23-45,01, P=0,020) quando comparados aos pacientes com níveis altos de esclerostina no tempo basal. Conclusão: Concentrações persistentemente baixas de esclerostina estão associados a inflamação contínua em pacientes com EA tratados com terapia anti-TNFa. / Introduction: Sclerostin levels have been reported to be low in ankylosing spondylitis (AS), but there is no data regarding the possible role of this Wnt inhibitor during anti tumor necrosis factor alpha (TNFa) therapy. Objectives: The present study longitudinally evaluated sclerostin levels, inflammatory markers and bone mineral density (BMD) in AS patients under anti-TNFa therapy. Methods: Thirty active AS patients were assessed at baseline, 6 and 12 months after anti-TNFa therapy regarding clinical parameters (BASDAI, BASFI, BASMI and ASQoL), inflammatory markers, BMD and baseline radiographic damage (mSASSS). Thirty age- and sex-matched healthy individuals comprised the control group. Patients\' sclerostin levels, sclerostin binding LRP6 and BMD were evaluated at the same time points and compared to controls. Results: At baseline, AS patients had lower sclerostin levels [60.5 (32.7) vs. 96.7 (52.9) pmol/l, P=0.002] and comparable sclerostin binding to LRP6 (P=0.387) than controls. Improvement of BASDAI, BASFI, BASMI, ASQoL was observed at baseline vs. 6 vs. 12 months (P<0.01). Concomitantly, a gradual increase in spine BMD (P<0.001) and a positive correlation between baseline mSASSS and spine BMD was found (r=0.468, P<0.01). Inflammatory parameters reduction was observed comparing baseline vs. 6 vs. 12 months (P<0.01). Sclerostin levels progressively increased [60.5 (32.7) vs. 67.1 (31.9) vs. 72.7 (32.3) pmol/l, P<0.001] after anti-TNFa treatment. At 12 months, the sclerostin levels remained significantly lower in patients compared to controls [72.7 (32.3) vs. 96.70 (52.85) pmol/l, P=0.038]. Moreover, sclerostin serum levels at 12 months were lower in the 10 patients with high CRP (=5mg/l) compared to the other 20 patients with normal CRP (P=0.004). Of note, these 10 patients with persistent inflammation also had lower sclerostin serum levels at baseline compared to the other patients (P=0.023). Univariate logistic regression analysis demonstrated that AS patients with lower sclerostin serum levels had an increased risk to have high CRP at 12 months (odds ratio=7.43, 95% CI 1.23-45.01, P=0.020) than those with higher sclerostin values. Conclusion: Persistent low sclerostin levels may underlie continuous inflammation in AS patients under anti-TNFa therapy.

Objetivo: investigar a capacidade osteoclastogênica de células mononucleares do sangue periférico (PBMCs) de pacientes do sexo masculino com espondilite anquilosante (EA), comparando com indivíduos saudáveis e determinar a relação da osteoclastogênese com parâmetros clínicos e laboratoriais. Métodos: células mononucleares do sangue periférico de 85 pacientes com espondilite anquilosante e 59 controles saudáveis (CT) foram marcadas para avaliar a presença de células CD16 positivas (precursores de osteoclastos). As PBMCs foram mantidas, in vitro, por 21 dias para indução da diferenciação em osteoclastos e avaliação da apoptose destas células. Os níveis séricos do ligante do receptor ativador de fator nuclear kB (RANKL), osteoprotegerina (OPG), telopeptídeo C-terminal do colágeno tipo I (CTX) e propeptídeo Nterminal do procolágeno tipo I (P1NP) foram também avaliados. Resultados: PBMCs de pacientes com EA apresentaram menor porcentagem de células CD16 positivas (25,06 ± 8,59 vs. 28,59 ± 10,20%; p = 0,026) e originaram menor número de osteoclastos comparados aos controles saudáveis (647,7 ± 669,4 vs. 764,4 ± 561,9 OC/poço; p = 0,014). A porcentagem de osteoclastos em apoptose foi menos frequente nos pacientes com EA versus CT (31,8 ± 32,5 vs. 44,5 ± 34,3%; p = 0,007). Menores relações RANKL/OPG e CTX/P1NP foram observadas nos pacientes com EA em relação aos CT (0,05 ± 0,03 vs. 0,07 ± 0,07; p = 0,046 e 0,008 ± 0,003 vs. 0,010 ± 0,003; p < 0,001, respectivamente). Pacientes com EA em uso de terapia de anti-inflamatório não-hormonal (AINH) não apresentaram diferença associada ao número de osteoclastos gerados e à porcentagem de células CD16 positivas comparados aos CT (p > 0,05). Entretanto, pacientes com EA em uso de terapia com inibidor de TNFalfa (iTNFalfa) demonstraram menor número de osteoclastos gerados comparados aos indivíduos saudáveis (582,51 ± 717,56 vs. 764,43 ± 561,9 OC/poço; p = 0,047). Observou-se uma correlação negativa entre número de osteoclastos gerados a partir de PBMC de pacientes com EA e duração de doença (R = -0,220, p = 0,043). Conclusões: os presentes resultados demonstraram que monócitos de pacientes com EA apresentam uma menor capacidade em gerar osteoclastos comparados a indivíduos saudáveis, e que a osteoclastogênese esteve correlacionada negativamente à duração de doença. Estes dados sugerem que os osteoclastos possuem um papel importante na fisiopatologia da doença óssea nos pacientes com EA / Objective: the aim of this study was to investigate if the osteoclastogenic capacity of PBMCs is different in AS patients compared to controls and the relationship between osteoclastogenesis and clinical/laboratory parameters. Methods: PBMCs from 85 male ankylosing spondylitis (AS) patients and 59 controls were tested for CD16+ cells and induced to differentiate into osteoclasts over 3 weeks in vitro. Serum levels of RANKL, osteoprotegerin (OPG), C-terminal telopeptide of type I collagen (CTX) and N-terminal propeptide of type 1 collagen (P1NP) were also evaluated. Results: PBMCs from AS patients had fewer CD16+ cells (25.06 ± 8.59 vs. 28.59 ± 10.20%; p = 0.026) and produced fewer osteoclasts (647.7 ± 669.4 vs. 764.4 ± 561.9 OC/well; p = 0.014) compared to controls. Apoptosis occurred less frequently in osteoclasts obtained from AS patients than in osteoclasts from the controls (31.8 ± 32.5 vs. 44.5 ± 34.3%; p = 0.007). A lower RANKL/OPG and CTX/P1NP were observed in AS patients compared to controls (0.05 ± 0.03 vs. 0.07 ± 0.07; p = 0.046 e 0.008 ± 0.003 vs. 0.010 ± 0.003; p < 0.001, respectively). AS patients taking NSAIDs presented no difference regarding the number of OCs produced and the percentage of CD16+ cells compared to controls (p > 0.05). However, patients taking TNFalpha inhibitors (TNFi) presented lower OC numbers than controls (582.51 ± 717.56 vs. 764.43 ± 561.9 OC/well; p = 0.047). A negative correlation was demonstrated between the number of osteoclasts generated from PBMCs of AS patients and disease duration (R = -0.220, p = 0.043). Conclusion: monocytes from male AS patients display a lower capacity to generate osteoclasts in vitro compared to cells from controls. Osteoclastogenesis was negatively correlated with disease duration. This finding supports the idea that osteoclasts play a role in the physiopathology of bone disease in AS patients