A dissertation submitted in partial compliance with the requirements for the Master's Degree in Technology: Chiropractic, Durban Institute of Technology, 2006. / To determine the efficacy of the Harpago and celery seed cream in mild to moderate degenerative joint disease of the knee in terms of subjective and objective clinical findings / M

Rheumatoid arthritis (RA) which affects 0.5-1% of the world population and is characterised by joint erosions and presence of the autoantibodies anti-citrullinated protein antibodies (ACPA) and rheumatoid factor. Collagen II (CII) is a joint-specific antigen and we have shown that antibodies against CII (anti-CII) are present in around 8% of RA patients. RA patients with anti-CII are characterized by acute RA onset with elevated CRP and early joint erosions at the time of RA onset. Polymorphonuclear granulocytes (PMN) and peripheral blood mononuclear cells (PBMC) are abundant in RA synovial fluids, where they can interact with anti-CII, thus forming immune complexes (IC) with CII. In my thesis I have shown that PMN upregulated the cell surface markers CD66b and CD11b and downregulated CD16 and CD32 after stimulation with anti-CII IC. These changes in CD66b and CD16 associated to joint erosions to a larger extent than did PBMC responses to anti-CII IC. PMN cocultured with PBMC and stimulated with anti-CII IC showed augmented chemokine production that was dependent on TLR4 and functionally active PMN enzymes. This mechanism can lead to accumulation of inflammatory cells in joints of RA patients who are anti-CII positive around the time of RA diagnosis, and may thus help explain the acute onset RA phenotype associated with anti-CII. In a large Swedish RA cohort, anti-CII associated with elevations in clinical and laboratory measures of disease activity at diagnosis and until 6 months, whereas ACPA associated with late inflammation. Anti-CII seropositive RA was associated with improvements in clinical measurements and was negatively associated with smoking in contrast to ACPA that was associated with worseneing of clinical symptoms and associated positively with smoking. Anti-CII levels associated to  HLADRB1*03 and  HLADRB1*01 whereas ACPA showed negative association to HLA-DRB1*03. In a Malaysian RA cohort anti-CII also associated to elevated CRP at the time of diagnosis. Anti-CII seropositive RA represents a distinct phenotype, in many respects representing the converse  to the clinical, genetic and smoking associations described for ACPA. Early determinations of anti-CII in parallel to ACPA predict the inflammatory outcome in RA.

Current therapies for chronic inflammatory diseases often abrogate the immune functions required to fight infections. Human cathelicidin host defence peptide (HDP) LL-37 selectively suppresses pathogen-induced inflammation, without compromising resistance to infections. These unique dual abilities of LL-37 make it a promising candidate as an alternative therapeutic for treating chronic inflammatory diseases. The objective of this study was to investigate the effects of LL-37 and its derivative peptide IG-19 in cytokine-mediated inflammation. I demonstrated that LL-37 and IG-19 selectively suppressed cytokine IL-32γ-induced pro-inflammatory cytokines, without compromising the production of anti-inflammatory cytokines, and chemokines in human PBMC and macrophages. However, significant quantitative differences between LL-37 and IG-19-mediated chemokine productions suggested that the mechanisms underlying the activity of these two peptides were different. I showed that both peptides suppressed IL-32γ-mediated phosphorylation of the Src-kinase FYN(Y420), known to enhance inflammation. Contrastingly, phosphorylation of the dual phosphatase MKP-1(S359), a negative regulator of inflammation, was enhanced in response to both peptides. Similarly, both peptides increased the activity of p44/42MAPK, which phosphorylates and stabilizes MKP-1. These results suggested that MKP-1 may be a critical mediator of the immunomodulatory activity of these peptides. Bioinformatic interrogation revealed that direct interacting protein partners of MKP-1 were overrepresented in MAPK and NF-κB signalling pathways. Both peptides enhanced the phosphorylation of p38MAPK. However, contrasting to LL-37, IG-19 did not mediate the phosphorylation of JNK MAPK and IKK-α signaling intermediates involved in inflammation. This was consistent with observations that chemokine production was significantly lower in response to IG-19 compared to LL-37. These results suggested that IG-19 may be a better immunomodulatory therapeutic candidate compared to LL-37. As cytokine-mediated inflammation plays critical roles in the disease pathogenesis of inflammatory arthritis, I examined the effects of exogenous administration of IG-19 in a murine model of collagen-induced arthritis. Administration of IG-19 decreased disease severity, suppressed pro-inflammatory cytokines and anti-collagen antibodies, and mitigated cartilage destruction in the CIA mice. These results provide a rationale to further develop IG-19 as a therapeutic agent for chronic inflammatory arthritis. The advantage of HDP based therapy is the potential to control inflammation without compromising the patient’s ability to resolve infections. / May 2017

Signals via the T cell receptor (TCR) are critical for the development of T cells in the thymus, maintenance of a self-tolerant peripheral T cell repertoire and the activation of T cells in secondary lymphoid organs. A dynamic balance between tyrosine phosphorylation and dephosphorylation is essential for the maintenance of homeostasis and proper regulation of the immune system. The cytoplasmic phosphatase, PTPN22 (protein tyrosine phosphatase non-receptor type 22) is involved in negative modulation of signal transduction through the TCR and plays a central role in regulating lymphocyte homeostasis. Genome wide association studies reveal that point mutations in PTPN22 confer an increased risk of developing multiple autoimmune diseases in humans. The precise function of PTPN22 and how mutations contribute to autoimmunity is controversial. Loss-of-function mutations in PTPN22 are associated with elevated T effector cell expansion and autoreactive B cells in both humans and mice. A thorough dissection of the molecular involvement of PTPN22 and its allelic variant R619W is important to delineate its role in autoimmunity, to this end we utilised the Ptpn22-/- mice generated in our laboratory. In order to address whether R619W allelic variant is a gain- or loss-of-function mutation, we expressed both PTPN22WT and PTPN22R619W constructs in primary activated Ptpn22-/- T lymphocytes using lentiviral transduction. Surprisingly expression of either wild type or variant phosphatase showed no affect on cytokine production. Preliminary results from bone marrow chimeras generated by retroviral expression of PTPN22WT and PTPN22R619W in Ptpn22 deficient mice showed reduced T cell activation compared to Ptpn22-/- T cells. PTPN22WT appeared to be more suppressive of T cell responses than variant PTPN22R619W. Consistent with studies conducted in comparable knock-in mouse models, our data point to the variant PTPN22R619W as being a partial loss of function allele. To elucidate the mechanism of PTPN22 action in context of an autoimmune disease, we investigated the effect of Ptpn22 deficiency on the phenotype of SKG mice. The SKG mouse harbours a point mutation (W163C) within the carboxyl terminal SH2- domain of ZAP-70, which results in decreased TCR signalling and impaired thymocyte development with defective positive and negative selection. These mice are prone to developing CD4+ T cell mediated autoimmune arthritis that closely resembles rheumatoid arthritis in humans. We found that thymus differentiation was partially restored in SKG Ptpn22-/- thymocytes and Ptpn22 deficiency enhanced TCR mediated signalling in SKG Ptpn22-/- thymocytes relative to SKG thymocytes. Consistent with increased signalling observed in the thymocytes, there was improved in vitro proliferation and IL-2 production of CD4+ T lymphocytes from SKG Ptpn22-/- mice compared to SKG mice. By contrast to SKG mice, SKG Ptpn22-/- mice developed less severe mannan-induced arthritis and showed decreased proportions of Th17 and higher numbers of regulatory T cells. These results show that removal of PTPN22 can compensate, at least partially, for the deficient ZAP-70 activity in the SKG mouse, thus linking PTPN22 and ZAP-70 to the same signalling pathway. This study advances our understanding of how manipulating TCR signals impacts on downstream T cell functions, suggesting PTPN22 may be a valuable target for the treatment of autoimmune diseases. Further studies to determine physiological role of the phosphatase and its disease-associated variants could provide insight into mechanism of immune activation, tolerance and autoimmunity.

Background: Arthritis interferes with quality of life, results in enormous medical and social costs, and is the leading cause of disability in the United States. Overweight and obesity have been found to be associated with specific types of arthritis, but the relationship between excess body weight and arthritis in general has not been well characterized at the population level. Furthermore, previous studies failed to utilize the CDC validated surveillance case definition of arthritis. Objectives: To examine the association between body mass index (BMI: kg/m2) and arthritis using the CDC validated surveillance case definition of arthritis and to describe the prevalence of arthritis across population subgroups based on body mass index and other select characteristics. Methods: Cross-sectional data from the 2005 Behavioral Risk Factor Surveillance System survey were analyzed. Using population weights, descriptive statistics and prevalences were generated. Univariate and multivariate analyses with 95% confidence intervals (CI) were conducted to examine the risk estimates (odds ratios/ORs) and to assess the relationship between body mass index and arthritis among U.S. adults, (N=356,112). SAS 9.1 software was used for all analyses.Results: Overall, 26% of US adults had self-reported arthritis. Obese persons (BMI: >30) were 2 times more likely to report arthritis compared to normal weight respondents, (BMI: 40): OR= 3.1, 95%CI= 2.9, 3.4; Class II Obesity, (BMI: 35-39.9): OR=2.4, 95% CI= 2.3, 2.6; Class I Obesity, (BMI: 30-34.9): OR= 2.0, 95% CI= 1.9, 2.1] The association between the BMI groups and arthritis did not change significantly after taking demographic and socioeconomic variables into account. Older age, female gender, higher income, and lack of any physical activity were associated with a higher odds of reporting arthritis, while insurance status and being non-White were not.Conclusions: BMI is an important independent risk factor for self-reported arthritis. Resources must be allocated to prevent and reduce weight gain in the population, especially among women and younger adults.

Class of 2006 Abstract / Objectives: To determine the effectiveness of etanercept therapy on C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), height, weight and body mass index (BMI) of patients with juvenile rheumatoid arthritis in an ambulatory pediatric clinic. Methods: This project used a pretest-posttest design that assessed patients before treatment with etanercept and then 6 months after the treatment was begun. Pre-treatment and post-treatment data were obtained through a retrospective chart review. A chart review was performed to collect each patient’s ESR, CRP, height, weight, BMI, and demographic data using a standardized data collection instrument. A paired t-test was performed to compare the pre-treatment and post-treatment data for the ESR, CRP, height, weight and BMI measurements. Results: Nine patients were identified that met the study inclusion. The mean age (SD) of the patients was 13.1 (4.4) years. Increases in weight and height parameters were seen after 6 months of etanercept treatment (p= 0.05, 0.002, respectively). There were no differences found in BMI, CRP and ESR parameters (p= 0.133, 0.753, 0.188, respectively) between the pre and post measurements. Conclusions: This pre-post analysis of 9 patients with juvenile rheumatoid arthritis found that etanercept therapy was associated with a significant gain in weight and height. However, this study found no differences in CRP or ESR after etanercept treatment. Additional research in larger populations is needed to more fully describe the changes in monitoring parameters following etanercept therapy.

O objetivo deste estudo foi avaliar os efeitos do probiótico Bifidobacterium animalis subsp. lactis HN019 (HN019) na periodontite (PE) induzida por ligadura em ratos com artrite reumatoide (AR) experimental. Foram utilizados 28 ratos, divididos em 4 grupos (n=7): AR (controle), AR/PROB (probiótico), AR/PE (periodontite experimental) e AR/PE/PROB. A partir do dia 0, HN019 foi adicionado diariamente à água dos animais dos grupos PROB, na concentração de 1,5x 109 unidades formadoras de colônia por mililitro, até o final do experimento. No dia 7, AR foi induzida por injeções subcutâneas de colágeno bovino tipo II (CII) emulsionado em Adjuvante Incompleto de Freund (IFA) em múltiplos locais na base da cauda dos animais. No dia 14, foi realizada uma dose de reforço de CII com IFA. No dia 21, aplicações locais de Adjuvante Completo de Freund foram realizadas na superfície plantar das patas traseiras direitas e intra-articularmente nos joelhos direitos dos animais. No dia 28, nos grupos PE, foram posicionadas ligaduras ao redor dos primeiros molares inferiores, as quais permaneceram em posição durante 11 dias. Os animais foram submetidos à eutanásia no 39º dia. Foram realizadas análises microtomográficas, histomorfométrica, imunoenzimáticas (anticorpo anti-proteína citrulinada, TNF-&alpha;, IL-6, IL-17 e IL-10) e microbiológica. Os dados foram estatisticamente analisados (p<0,05). O grupo AR/PE/PROB apresentou perda óssea alveolar reduzida quando comparado com o grupo AR/PE. Não houve diferença significativa em relação ao nível de inserção conjuntiva quando os animais com PE tratados e não tratados com PROB foram comparados. Os animais do grupo AR/PROB apresentaram níveis de anticorpo anti-proteína citrulinada diminuídos quando comparados com os animais dos grupos AR e AR/PE. Os animais com PE tratados com PROB apresentaram níveis de TNF-&alpha; e IL-6 reduzidos e níveis de IL-17 aumentados quando comparados com os animais com PE não tratados. Não houve diferença significativa em relação aos níveis de IL-10 entre os grupos AR/PE e AR/PE/PROB. O grupo AR/PE apresentou maior taxa de bactérias anaeróbias sobre aeróbias do que o grupo AR/PE/PROB. Dentro dos limites deste estudo, pode-se concluir que a administração de HN019 promoveu um efeito protetor contra a destruição tecidual em ratos com AR e PE experimentais / The purpose of this study was to evaluate the effects of the probiotic Bifidobacterium animalis subsp. lactis HN019 (HN019) on ligature-induced periodontitis in rats with experimental rheumatoid arthritis (RA). 28 rats were divided into 4 groups (n = 7): RA (control), RA/PROB (probiotic), RA/EP (experimental periodontitis) and RA/EP/PROB. Starting from day 0, HN019 was added daily to the water of the animals of PROB groups (1.5x109 colony forming units per milliliter), until the end of the experiment. On day 7, RA was induced by subcutaneous injections of bovine collagen type II (CII) emulsified in Incomplete Freund\'s Adjuvant (IFA) at multiple sites at the base of the animals tail. On day 14, a booster dose of CII was performed with IFA. On day 21, local applications of Complete Freund\'s Adjuvant were performed in the plantar surface of the right hind paws and intra-articularly in the right knees of the animals. On day 28, in EP groups, ligatures were positioned around mandibular first molars and remained in position for 11 days. The animals were euthanized on day 39. Microtomographic, histomorphometric, immunoenzymatic (anti-citrullinated protein antibodies, TNF-&alpha;, IL-6, IL-17 and IL-10) and microbiological analyses were performed. Data were statistically analyzed (p <0.05). The RA/EP/PROB group presented reduced alveolar bone loss when compared to the RA/EP group. There was no significant difference regarding connective tissue attachment level when the treated and untreated EP animals were compared. Animals of the RA/PROB group showed decreased levels of anti-citrullinated protein antibodies when compared with the animals of RA and RA/EP groups. EP animals treated with PROB presented reduced levels of TNF-&alpha; and IL-6 and increased levels of IL-17 when compared with animals with untreated EP. There was no significant difference in IL-10 levels between RA/EP and RA/EP/PROB groups. Group RA/EP presented a higher rate of anaerobic/aerobic bacteria than group RA/EP/PROB. Within the limits of this study, it can be concluded that the administration of HN019 promoted a protective effect against tissue destruction in rats with experimental RA and EP

Charles University, Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Daniel Diviš Supervisors: Prof. Dr. Florence Apparailly, Directrice de Recherche Prof. PharmDr. Petr Pávek, Ph.D. (formal tutor) Title of diploma thesis: The role of miR-150 in the physiopathology of oligoarticular juvenile idiopathic arthritis Juvenile idiopathic arthritis (JIA) is the most common chronic rheumatoid disease affecting children, and its pathological mechanisms are still poorly understood. Innate and adaptive immunity including myeloid cells play a major role in these processes. Epigenetic deregulations along with non-coding microRNAs have been reported in many inflammatory diseases. Moreover, preliminary results obtained by the research group of Prof. Florence Apparailly showed accumulation of intermediate monocytes along with the high expression of miR-150 in the synovial fluid of children affected by oligoarticular JIA. Based on these findings a hypothesis has been postulated suggesting that miR-150 could have a role in the pathogenesis of this disease and in the regulation of monocyte differentiation and function. To study the impact of miR-150 on monocytes from the peripheral blood of healthy donors, transfection experiments were performed to neutralize miR-150. The...

Die rheumatoide Arthritis (RA) ist eine Autoimmunerkrankung, die durch anhaltende Gelenksentzündungen gekennzeichnet ist und mit einer fortschreitenden Degradierung des Knorpels und Knochen einhergeht. Ungefähr 2 % der erwachsenen Bevölkerung weltweit sind betroffen und leiden unter erheblichen Gelenkschmerzen und Beeinträchtigungen. Der intraartikuläre Transfer anti-entzündlicher Gene (z.B. des Interleukin-1 Rezeptorantagonisten – IL1RA) zeigte signifikante Bedeutung in präklinischen und Phase-I klinischen Studien der RA Therapie. Die meisten dieser Studien verwendeten MLV-basierte orthoretrovirale Vektoren für eine stabile Transgenexpression, tragen aber das Risiko der Insertionsmutagenese. Wir haben foamyvirale Vektoren (FVV) etabliert, welche von apathogenen Elternviren abgeleitet sind und sich durch ein breites Wirtsspektrum und ein vorteilhaftes Integrationsmuster ins zelluläre Genom auszeichnen. In dieser Arbeit wurden IL1RA exprimierende prototypische foamyvirale Vektoren (PFV) generiert, deren chondroprotektives Potential in vitro und in einem indirekten Gentransferansatz in Kniegelenken von Wistar und athymischen Nacktratten in vivo evaluiert wurde. PFV Vektoren mit der kodierenden Sequenz für den humanen IL1RA, einer internen ribosomalen Eintrittsstelle (IRES) und EGFP wurden generiert und mit Verwendung eines Vier-Plasmidsystem, bestehend aus dem Vektorplasmid (IL1RA-IRES-EGFP) und den Expressionsplasmiden FV-gag, FV-pol und FV-env in 293T Zellen produziert. Ebenso wurden Kontrollvektoren welche nur EGFP exprimieren generiert. Transduktionsexperimente wurden mit primären humanen mesenchymalen Stammzellen (MSZ) aus Knochenmarkaspiraten, der Tert-4 mesenchymalen Stammzelllinie, HT1080 Fibroblasten und primären Ratten Synovialfibroblasten durchgeführt. Die Transgenexpression wurde mittels Fluoreszenzmikroskopie (EGFP), ELISA (IL1RA) und quantitativer Real-Time PCR (IL1RA) evaluiert. Die Funktionalität des IL1RA-Proteins wurde mit einem Prostaglandin E2 (PGE2) Assay gezeigt. Dazu wurden FV.IL1RA transduzierte Tert-4 Zellen und unbehandelte Zellen mit 10 ng/ml IL1 inkubiert. Als readout für die IL1-Stimulation dienten die PGE2 Mengen in den konditionierten Medien. Die Zellkulturüberstände wurden 48 h nach IL1-Gabe auf ihren PGE2 und IL1RA Gehalt hin untersucht. Die PGE2 Menge war dabei, im Vergleich zu den unbehandelten Kontrollen, in den FV.IL1RA transduzierten Zellen signifikant erniedrigt. Nach der Transplantation von foamyviral transduzierten Synovialfibroblasten in Kniegelenke von Wistar und athymischen Nacktratten, war die intraartikuläre (i.a.) Transgenexpression in den Wistar Ratten zunächst hoch, fiel jedoch nach ungefähr 3 Wochen ab. Im Gegensatz dazu war die foamyviral vermittelte IL1RA-Expression in den immundefizienten Ratten für 12 Wochen auf sehr hohen Leveln stabil. Ein Maximum wurde an Tag 10 nach i.a. Transplantation mit ca. 450 ng pro Gelenk erreicht. Untersuchungen zur Biodistribution zeigten keine extraartikuläre Transgenexpression in allen untersuchten Organen (Gehirn, Herz, Lunge, Leber, Niere, Milz, Gonaden und Serum). Diese Resultate, zusammen mit dem Ausbleiben von sekundären Erkrankungen, wie bspw. Tumoren, in allen behandelten Tieren, sprechen für die Sicherheit des Ansatzes. Die Arbeit zeigt, dass FVV verwendet werden können, um primäre Synovialfibroblasten und MSZ effizient mit Markergenen und dem anti-entzündlichen IL1RA Transgen zu transduzieren. Die dabei erzielten Transgenlevel sind in der Lage, die Effekte von hochdosiertem IL1 zu blockieren. Die Ergebnisse sprechen dafür, dass FVV sehr effiziente Werkzeuge für den ex vivo Gentransfer sind und unterstreichen ihr großes Potential für die Bereitstellung anti-entzündlicher Transgene in primären Zellen und Geweben. Zukünftig soll diese Technologie in Tiermodellen der Arthritis angewendet werden. Das Fernziel der Arbeiten besteht in der Etablierung und Evaluierung eines Gentransfersystems, welches die in vivo Applikation am Menschen erlaubt. / Rheuamtoid arthritis (RA) is an autoimmune disease with persistent joint inflammation that results in progressive degradation of cartilage and bone. Approximately 2 % of the adult population worldwide are estimated to be affected by RA and suffer from substantial joint pain and disability. The intra-articular transfer of anti-inflammatory genes (e.g. interleukin receptor antagonist protein – IL1RA) showed significant impact in preclinical and early phase clinical trials for RA therapy. Most of these studies used MLV-based orthoretroviral vectors for stable transgene expression, but carry the risk of insertional mutagenesis. We have established foamyviral vectors (FVV) that are derived from apathogenic parent viruses and are characterized by a broad host range and a favourable integration pattern into the cellular genome. Here we used prototype foamyvirus vectors (PFV) that expressed IL1RA and evaluated their protective effects in vitro and in an indirect gene transfer approach in knee joints of Wistar and athymic nude rats in vivo. PFV vectors carrying the coding sequence of the human IL1RA gene, along with EGFP (enhanced green fluorescent protein) linked via an internal ribosomal entry site (IRES), were generated and produced by using a four-plasmid system consisting of the vector plasmid (IL1RA-IRES-EGFP) and the expression plasmids FV-gag, FV-pol and FV-env in 293T cells. Control vectors were also generated that expressed EGFP only. Transduction experiments were performed with different cells including human primary mesenchymal stem cells (MSC) derived from bone marrow-aspirates, the Tert-4 mesenchymal stem cell line, the HT1080 fibroblast cell line and primary rat synovial fibroblasts. The transgene expression was evaluated by fluorescence microscopy (EGFP), flow cytometry (EGFP), ELISA (IL1RA) and realtime polymerase chain reaction (PCR) (IL1RA). Functionality of the IL1RA protein was shown by using a Prostaglandin E2 (PGE2) Assay. For this, FV.IL1RA transduced Tert-4 cells and untreated Tert-4 cells were incubated with 10 ng/ml IL1. As a readout for the IL1 stimulation, levels of PGE2 in conditioned media were determined. Cell culture supernatants were assayed 48 hours later for their PGE2 and IL1RA levels. The PGE2 levels were statistically significantly lower in the FV.IL1RA transduced cells in comparison to untreated controls. After the transplantation of foamyviral-transduced synovial fibroblasts in knee joints of Wistar and athymic nude rats, the intra-articular transgene expression in Wistar rats was initially high and declined after approximately 3 weeks. In contrast, foamyviral-mediated expression of human IL1RA was found to persist for at least 12 weeks at very high levels in immunocompromised rats, with a maximun value of approximately 450 ng human IL1RA per joint at day 10 after intra-articular transplantation. Biodistribution experiments were also performed and revealed the absence of extra-articular transgene expression in all organs analyzed (brain, heart, lung, liver, kidney, spleen, gonad and serum). This finding, along with the nonappearance of secondary disorders such as tumors in all animals treated, argue for the safety of the approach. Here we show that FV vectors can be used to efficiently transduce primary synovial fibroblasts as well as primary MSCs with marker genes as well as the anti-inflammatory IL1RA transgene at levels that were functional to block the effects of high doses of IL1. The results indicate that FV vectors are very efficient tools for ex vivo gene transfer and underscore their high value for delivering antiinflammatory transgenes to primary cells and tissues. In future experiments we aim to apply this technology in animal models of disease. The ultimate goal of this research is the establishment and evaluation of a gene transfer system that allows the application in humans.

Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease that leads to destruction of articular cartilage and subchondral bone at the synovial joints. Clinically, RA is characterized by swelling, tenderness and destruction of synovial joints, which results in severe disability and premature mortality. In the RA disease state, inflammation in the synovial compartment is regulated by a complex cytokine and chemokine network, including tumor necrosis factor α (TNFα), which has been clinically demonstrated a key mediator of RA pathogenesis. TNFα can be found in elevated levels in the synovial fluid and serum of RA patients and the role of the cytokine in both the inflammation and bone destruction of RA suggests it is important in the understanding of disease progression as well as the development of therapeutic targets. Many of the biological processes that mediate RA, including bone turnover and cartilage resorption, involve signaling pathways that are mediated by adenosine and its receptors. The A2B adenosine receptor (A2BAR) is highly expressed in the synoviocytes of RA patients and the receptor has a similar expression profile in humans and mice. The goal of this thesis was to use a mouse model of RA to understand how the A2B adenosine receptor modulates TNFα and other destructive enzymes that contribute to the progression of the disease. A collagen antibody-induced arthritis (CAIA) mouse model was used to determine the effect of A2BAR ablation on systemic and joint-specific TNFα expression. Comparable arthritic conditions were observed in CAIA mice of both A2BAR knockout (KO) and wild-type (WT) genotypes and the absence of the A2BAR gene did not result in any observable differences in the gross arthritic state created in each genotype. Immunohistochemistry analysis of TNFα expression in mouse paws revealed that paw joints from CAIA A2BAR KO mice exhibited more robust TNFα staining compared to CAIA WT specimens of the same treatment duration. ELISA analysis of the serum showed that only CAIA A2BAR KO mice had greater serum production of TNFα at day 10 after induction of arthritis. TNFα and matrix metalloproteinase-9 mRNA expression were also elevated in KO CAIA knee joints in comparison to WT CAIA knee joints; however, WT CAIA mice were found to have higher levels of aggrecanase mRNA compared to KO mice. These results suggest that while the loss of A2BAR activity leads to a hyper-inflammatory state, the A2B adenosine receptor alone is not responsible for the progressive inflammation of the synovial joints associated with rheumatoid arthritis.