Pathology publications
Permanent URI for this collection
Browse
Browsing Pathology publications by Author "Ahern, M."
Now showing 1 - 7 of 7
Results Per Page
Sort Options
Item Metadata only Effects of pulse methylprednisolone on inflammatory mediators in peripheral blood, synovial fluid, and synovial membrane in rheumatoid arthritis(WILEY, 1997) Youssef, P.; Haynes, D.; Triantafillou, S.; Parker, A.; Gamble, J.; Roberts-Thomson, P.; Ahern, M.; Smith, M.Objective
To establish whether the clinical efficacy of pulse methylprednisolone (MP; 1,000 mg intravenously) is related to the modulation of proinflammatory cytokines within the peripheral blood, synovial membrane, or synovial fluid compartments.Methods
Eighteen patients with active rheumatoid arthritis (RA) were studied. Peripheral blood (11 patients) and knee synovial fluid (9 patients, 10 knees) were obtained before and at 4 and 24 hours after MP therapy. Interleukin-1beta (IL-1beta), IL-8, and tumor necrosis factor alpha (TNFalpha) were measured by enzyme-linked immunosorbent assay and biologic assays; prostaglandin E2 (PGE2) was measured by competitive radioimmunoassay. In 10 patients, arthroscopically directed synovial biopsies were obtained before and at 24 hours after treatment, at disease relapse (4 patients), and after retreatment (1 patient). Membranes were stained by immunohistochemical techniques with monoclonal antibodies against TNFalpha, IL-8, IL-1beta, and the IL-1 receptor antagonist protein (IL-1Ra).Results
MP therapy was associated with a rapid (within 24 hours) and substantial decrease in the expression of TNFalpha in the lining and sublining regions of the synovial membrane, as well as substantial decreases in the levels of TNFalpha in serum and synovial fluid. There was also reduced IL-8 expression in the synovial lining, as well as reduced synovial fluid IL-8 levels. No effect on synovial membrane IL-1beta and IL-1Ra or synovial fluid IL-1beta and PGE2 was found.Conclusion
MP therapy rapidly reduces IL-8 and TNFalpha levels in the synovial compartment, with cytokine changes in the serum and synovial fluid reflecting the changes in the synovial membrane. Alterations in TNFalpha expression in the synovial membrane correlated with clinical response to, and subsequent relapse after, MP therapy.Item Open Access Elevated expression of caspase-3 inhibitors, survivin and xIAP correlates with low levels of apoptosis in active rheumatoid synovium(BioMed Central, 2009) Dharmapatni, A.; Smith, M.; Findlay, D.; Holding, C.; Evdokiou, A.; Ahern, M.; Weedon, H.; Chen, P.; Screaton, G.; Xu, X.; Haynes, D.Introduction: Tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) is a tumour necrosis factor (TNF) family member capable of inducing apoptosis in many cell types. Methods: Using immunohistochemistry, terminal deoxynucleotidyl transferase biotin-dUTP nick end labelling (TUNEL) and real-time PCR we investigated the expression of TRAIL, TRAIL receptors and several key molecules of the intracellular apoptotic pathway in human synovial tissues from various types of arthritis and normal controls. Synovial tissues from patients with active rheumatoid arthritis (RA), inactive RA, osteoarthritis (OA) or spondyloarthritis (SpA) and normal individuals were studied. Results Significantly higher levels of TRAIL, TRAIL R1, TRAIL R2 and TRAIL R4 were observed in synovial tissues from patients with active RA compared with normal controls (p < 0.05). TRAIL, TRAIL R1 and TRAIL R4 were expressed by many of the cells expressing CD68 (macrophages). Lower levels of TUNEL but higher levels of cleaved caspase-3 staining were detected in tissue from active RA compared with inactive RA patients (p < 0.05). Higher levels of survivin and x-linked inhibitor of apoptosis protein (xIAP) were expressed in active RA synovial tissues compared with inactive RA observed at both the protein and mRNA levels. Conclusions: This study indicates that the induction of apoptosis in active RA synovial tissues is inhibited despite stimulation of the intracellular pathway(s) that lead to apoptosis. This inhibition of apoptosis was observed downstream of caspase-3 and may involve the caspase-3 inhibitors, survivin and xIAP.Item Metadata only Histopathological and ultrastructural features of dermal telangiectasias in systemic sclerosis(Taylor & Francis, 2005) Walker, J.; Stirling, J.; Beroukas, D.; Dharmapatni, A.; Haynes, D.; Smith, M.; Ahern, M.; Roberts-Thomson, P.Aims: To investigate the histological, ultrastructural and immunohistochemical features of the vascular lining of dermal telangiectasia, a characteristic clinical finding in scleroderma. Methods: Standard histological, electron microscopic and immunohistological techniques were used to examine dermal telangiectasias in five patients with limited scleroderma, the most common scleroderma variant in Caucasian populations. Results: The telangiectasias were dilated postcapillary venules located in the papillary and superficial reticular dermis. The vessel walls consisted of non‐fenestrated endothelial cells surrounded by a variable number of pericytes and smooth muscle cells. There were no unique ultrastructural features. Thickened collagen fibres in the reticular or deep dermis were seen in all but one patient, although in variable and generally minimal quantities. Surrounding infiltrating inflammatory cells were scarce. No enhanced endothelial staining was obtained with antibodies directed against endoglin, endothelin, E‐selectin and ICAM‐1 suggesting a resting or inactivated state. Conclusion: The immunohistological and ultrastructural features of the lining endothelium of established telangiectasias in long‐standing, limited scleroderma appear benign. It would be of interest to examine telangiectasias in the early phase of their formation. Alternatively, other explanations need to be explored in understanding the aetiopathogenesis of telangiectasia in scleroderma.Item Metadata only Modulation of RANKL and osteoprotegerin expression in synovial tissue from patients with rheumatoid arthritis in response to disease-modifying antirheumatic drug treatment and correlation with radiologic outcome(Wiley-Liss, 2008) Haynes, D.; Crotti, T.; Weedon, H.; Slavotinek, J.; Au, V.; Coleman, M.; Roberts-Thomson, P.; Ahern, M.; Smith, M.Objective To demonstrate the effect of treatment with disease-modifying agents on the expression of osteoprotegerin (OPG) and RANKL in the synovial tissue from rheumatoid arthritis (RA) patients and to correlate these changes with radiologic damage measured on sequential radiographs of the hands and feet. Methods Synovial biopsy specimens were obtained at arthroscopy from 25 patients with active RA (16 of whom had a disease duration <12 months) before and at 3–6-month intervals after starting treatment with a disease-modifying agent. Immunohistologic analysis was performed using monoclonal antibodies to detect OPG and RANKL expression, with staining quantitated using computer-assisted image analysis and semiquantitative analysis techniques. Serial radiographs of the hands and feet were analyzed independently by 2 radiologists and a rheumatologist using the van der Heide modification of the Sharp scoring method. Results Thirteen patients achieved a low disease state as defined by a disease activity score <2.6 while 19 patients achieved an American College of Rheumatology response >20% after disease-modifying antirheumatic drug (DMARD) treatment. Successful DMARD treatment resulted in an increase in OPG expression and a decrease in RANKL expression at the synovial tissue level, which correlated with a reduction in erosion scores measured on annual radiographs of the hands and feet. Conclusion Successful treatment-induced modulation of OPG and RANKL expression at the synovial tissue level, resulting in a reduction in the RANKL:OPG ratio, is likely to have a significant impact on osteoclast formation and joint damage in patients with active RA.Item Metadata only Receptor activator NF kB ligand (RANKL) and osteoprotegerin (OPG) protein expression in periodontitis(Munksgaard Int Publ Ltd, 2003) Crotti, T.; Smith, M.; Hirsch, R.; Soukoulis, S.; Weedon, H.; Capone, M.; Ahern, M.; Haynes, D.Objectives and background: This study investigated the expression of key mediators that regulate differentiation of osteoclasts, receptor activator of nuclear factor κB ligand (RANKL), and its natural inhibitor, osteoprotegerin (OPG), in periodontitis. We aimed to compare the levels of the RANKL and OPG in the granulomatous tissue adjacent to areas of alveolar bone loss from patients with periodontitis to that present in tissue from patients without periodontitis. In addition, we aimed to determine the types of cells expressing these factors in these tissues and to demonstrate the expression of the osteoclastic markers, RANK and tartrate-resistant acid phosphatase (TRAP), in periodontitis. Materials and methods: Frozen biopsy specimens were analysed using specific monoclonal antibodies and were evaluated by semiquantitative analysis and digital image analysis to compare levels of RANKL and OPG protein expression. Double labelling of frozen sections with antibodies to different cell lineage specific markers was used to determine the types of cells expressing these proteins. In situ hybridization was used to detect cells expressing RANK mRNA. Results: Semiquantitative image analysis demonstrated that significantly higher levels of RANKL protein (P < 0.05) were expressed in the periodontitis tissue. Conversely, OPG protein was significantly lower (P < 0.05) in the periodontitis tissues. RANKL protein was associated with lymphocytes and macrophages. OPG protein was associated with endothelial cells in both tissues. Many leukocytes expressing RANK mRNA and TRAP were observed in periodontitis tissues. Conclusion: The change in the levels of these key regulators of osteoclast differentiation may play a major role in the bone loss seen in periodontitis.Item Open Access Receptor activator NFκB ligand (RANKL) expression in synovial tissue from patients with rheumatoid arthritis, spondyloarthropathy, osteoarthritis, and from normal patients: semiquantitative and quantitative analysis(British Med Journal Publ Group, 2002) Crotti, T.; Smith, M.; Weedon, H.; Ahern, M.; Findlay, D.; Kraan, M.; Tak, P.; Haynes, D.Objectives: To compare receptor activator of NF-kB ligand (RANKL) production in the synovial tissue from patients with active rheumatoid arthritis (RA), inactive RA, spondyloarthropathies (SpA), osteoarthritis, and from normal subjects. In addition, to establish the cell lineages expressing RANKL in these tissues. Methods: Immunohistological analysis of frozen synovial tissue biopsy specimens was performed using a monoclonal antibody (mAb) to detect RANKL. Sections were evaluated by computer assisted image analysis and semiquantitative analysis to compare RANKL expression between groups. Dual and sequential labelling with mAb RANKL and cell lineage specific monoclonal antibodies were used to determine the types of cells expressing RANKL. Results: Higher levels of RANKL were expressed in tissues from patients with active RA and SpA than in tissues from patients with inactive RA, osteoarthritis, and from normal subjects. RANKL protein was associated with CD3 antigen-positive lymphocytes and some macrophages. RANKL was predominantly associated with activated, memory T cells (CD45Ro positive cells) in patients with active RA and spondyloarthropathy (SpA). Conclusions: The highest levels of RANKL were detected in patients with RA with active synovitis and in some patients with SpA. An increase in RANKL in the inflamed joint of patients with RA, produced by infiltrating activated T cells and macrophages, is likely to be an important cause of joint erosions in RA.Item Metadata only Variability of RANKL and osteoprotegerin staining in synovial tissue from patients with active rheumatoid arthritis: Quantification using color video image analysis(J Rheumatol Publ Co, 2003) Crotti, T.; Ahern, M.; Lange, K.; Weedon, H.; Coleman, M.; Roberts-Thomson, P.; Haynes, D.; Smith, M.Objective
To assess the interpatient, interbiopsy, and intrabiopsy variability of receptor activator of nuclear factor kB ligand (RANKL) and osteoprotegerin (OPG) immunostaining within synovial tissue from rheumatoid knee joints with active synovitis, using digital image analysis.Methods
Synovial biopsy specimens were obtained from patients with rheumatoid arthritis (RA) and active synovitis. Immunohistologic analysis was performed on frozen synovial tissue biopsy specimens from 6 patients using a monoclonal antibody (Mab) to detect RANKL (626) or OPG (805 or 8051). Patients with a minimum of 4 synovial biopsies were included in the study. Sections were evaluated by computer assisted image analysis to assess between-patient, between-biopsy, and intra-biopsy variability of OPG and RANKL protein expression. The study was designed to deliberately maximize the variability.Results
Computerized image analysis of staining with Mab to RANKL and OPG revealed variance for each antibody across the 3 components of the total variability.Conclusion
Our study shows that variability in synovial immunostaining of RANKL and OPG protein is a significant and complex problem. We discuss methods to reduce this variability and suggest that the auspices of OMERACT may be employed to advance the study of synovium in collaborative international studies.