Sialic Acid Residues Are Essential for the Anaphylactic Activity of Murine IgG1 Antibodies

Glycosylation of the Ab molecule is essential for maintaining the functional structure of Fc region and consequently for Ab-mediated effector functions, such as binding to cells or complement system activation. Alterations in the composition of the sugar moiety can dramatically influence Ab activity; however, it is not completely clear how differences in the N-linked oligosaccharide structure impact the biological function of Abs. We have described that murine IgG1 Abs can be separated according to their ability to elicit in vivo anaphylaxis in a fraction of anaphylactic and other of non-anaphylactic molecules. Furthermore, we showed that the N-linked oligosaccharide chain is essential for the structural conformation of the anaphylactic IgG1, the binding to Fc gamma RIII on mast cells, and, consequently, for the ability to mediate anaphylactic reactions. In this study, we evaluated the contribution of individual sugar residues to this biological function. Differences in the glycan composition were observed when we analyzed oligosaccharide chains from anaphylactic or non-anaphylactic IgG1, mainly the presence of more sialic acid and fucose residues in anaphylactic molecules. Interestingly, the enzymatic removal of terminal sialic acid residues in anaphylactic IgG1 resulted in loss of the ability to trigger mast cell degranulation and in vivo anaphylactic reaction, similarly to the deglycosylated IgG1 Ab. In contrast, fucose removal did not affect the anaphylactic function. Therefore, we demonstrated that the ability of murine IgG1 Abs to mediate anaphylaxis is directly dependent on the amount of sialic acid residues associated to the oligosaccharide chain attached to the Fc region of these molecules. The Journal of Immunology, 2008, 181: 8308-8314.

QUALITY OF LIFE IN SYSTEMIC LUPUS ERYTHEMATOSUS PATIENTS IN NORTHEASTERN BRAZIL: IS HEALTH-RELATED QUALITY OF LIFE A PREDICTOR OF SURVIVAL FOR THESE PATIENTS?

Objective: To identify social, demographic and clinical characteristics that influence survival of patients with systemic lupus erythematosus (SLE). Methods: Sixty-three patients with a diagnosis of SLE were studied at our medical services in 1999 and then reviewed in 2005. We utilized a protocol to obtain demographic and clinical traits, activity and damage indices, and health-related quality of life via the SF-36. All statistical tests were performed using a significance level of 5%. Results: Out of the 63 patients examined in 1999, six died, four were lost for the follow-up and the previous protocol was applied to the remaining 53 patients. The six patients who died presented the worst recorded health-related quality of fife, in all aspects. The most important observed predictor of death was a mean lower score in the Role-Emotional Domain of the mental health component of the SF-36 (p<0.01). Conclusion: Health-related quality of life may be used as possible predictive factor of mortality among patients with SLE.

Serum amyloid A induces reactive oxygen species (ROS) production and proliferation of fibroblast

Serum amyloid A (SAA) levels are elevated highly in acute phase response and elevated slightly and persistently in chronic diseases such as rheumatoid arthritis and diabetes. Given that fibroblasts exert profound effects on progression of inflammatory chronic diseases, the aim of this study was to investigate the response of fibroblasts to SAA. A dose-dependent increase in O(2)(-) levels was observed by treatment of fibroblasts with SAA (r = 0.99 and P <= 0.001). In addition, the expression of p47-phox was up-regulated by SAA (P < 0.001) and diphenyliodonium (DPI), a nicotinamide adenine dinucleotide phosphate (NADPH) oxidase inhibitor, reduced the release of O(2)(-) by 50%. Also, SAA raised fibroblast proliferation (P < 0.001) and this effect was completely abolished by the addition of anti-oxidants (P < 0.001). These findings support the notion that, in chronic inflammatory sites, SAA activated fibroblast proliferation and ROS production.

The impact of chronic illness on relationships in early adulthood: a comparison study between healthy and arthritic young adults

While engaging in romantic relationships is regarded as a normative task during young adulthood, non-normative life events such as the emergence of chronic illness can mitigate against the successful negotiation of such tasks. Chronic illness brings with it a series of additional challenges and stressors to the realm of personal relationships that are thought to interrupt the development of normative interpersonal and intra-individual processes. However, few studies have examined how young adults faced with a chronic illness such as arthritis navigate romantic relationships and the consequences of illness and relationships on psychological adjustment. The aim of the study was to compare the relationship experiences of healthy young adults with those faced with arthritis. One hundred and nine young adults (M 23.01 years, SD 2.43) took part in the study. Of these participants 41 had been diagnosed with arthritis. A univariate MANOVA revealed arthritic young adults reported significantly more insecure attachment, lower levels of readiness for intimacy, and poorer relationship satisfaction compared to healthy young adults. Further correlational and regression analyses on the arthritic sample revealed psychological adjustment was related to arthritis severity, attachment and components of coping. Findings will be discussed in relation to attachment theory and coping processes.

Attachment bonding and the receipt of care in the face of chronic illness

The relationship between social support and the mental health outcomes of chronic illness sufferers is regarded as complex with inconsistent findings across studies. More recently, researchers have argued that that these inconsistencies may be explained by attachment theory. In this preliminary study, we explored how attachment bonds with three distinct attachment figures – parents, best friends and romantic partners influenced arthritic young adults’ seeking of care. Forty-one arthritis sufferers aged between 18 and 33 years were administered an online questionnaire which included measures of attachment and the receipt of emotional and instrumental care. Significant differences were found in young adults’ attachment avoidance and anxiety ratings, and seeking of instrumental care across parents, best friends and romantic partners. These differences were associated with differences in the frequency and type of care received by young arthritis sufferers across the three attachment figures. Furthermore, arthritis severity was associated with the receipt of care from attachment figures however this relationship was partially mediated by attachment anxiety.

Safety and efficacy of routine postoperative ibuprofen for pain and disability related to ectopic bone formation after hip replacement surgery (HIPAID): a randomised control trial

Objectives To determine the benefits and risks of a non-steroidal anti-inflammatory drug (NSAID) as prophylaxis for ectopic bone formation in patients undergoing total hip replacement (or revision) surgery.
Design Double blind randomised placebo controlled clinical trial, stratified by treatment site and surgery (primary or revision).
Setting 20 orthopaedic surgery centres in Australia and New Zealand.
Participants 902 patients undergoing elective primary or revision total hip replacement surgery.
Intervention 14 days' treatment with ibuprofen (1200 mg daily) or matching placebo started within 24 hours of surgery.
Main outcome measures Changes in self reported hip pain and physical function 6 to 12 months after surgery (Western Ontario and McMaster University Arthritis index).
Results There were no significant differences between the groups for improvements in hip pain (mean difference -0.1, 95% confidence interval -0.4 to 0.2, P = 0.6) or physical function (-0.1, -0.4 to 0.2, P = 0.5), despite a decreased risk of ectopic bone formation (relative risk 0.69, 0.56 to 0.83) associated with ibuprofen. There was a significantly increased risk of major bleeding complications in the ibuprofen group during the admission period (2.09, 1.00 to 4.39).
Conclusions These data do not support the use of routine prophylaxis with NSAIDs in patients undergoing total hip replacement surgery.
Trial registration NCT00145730.

Protein kinase C isozymes as potential therapeutic targets in immune disorders

Background: Members of the protein kinase C (PKC) family are key signalling mediators in immune responses, and pharmacological inhibition of PKCs may be useful for treating immune-mediated diseases. Objective: To review and discuss the insights gained so far into various PKC isozymes and the therapeutic potential and challenges of developing PKC inhibitors for immune disorder therapy. Methods: A literature review of the role of PKCs in immune cell signalling and recent studies describing immune functions associated with PKC isozyme deficiency in relevant mouse disease models, followed by specific case studies of current and potential therapeutic strategies targeting PKCs. Results/conclusion: There is vast amount of data supporting PKC isozymes as attractive drug targets for certain immune disorders. Although the development of specific PKC isozyme inhibitors has been challenging, some progress has been made. It remains to be seen if broad-scale or isozyme-selective inhibition of PKC will have clinical efficacy.

Adamts5, the gene encoding a proteoglycan-degrading metalloprotease, is expressed by specific cell lineages during mouse embryonic development and in adult tissues.

The secreted metalloprotease ADAMTS5 is implicated in destruction of the cartilage proteoglycan aggrecan in arthritis, but its physiological functions are unknown. Its expression profile during embryogenesis and in adult tissues is therefore of considerable interest. β-Galactosidase (β-gal) histochemistry, enabled by a LacZ cassette inserted in the Adamts5 locus, and validated by in situ hybridization with an Adamts5 cRNA probe and ADAMTS5 immunohistochemistry, was used to profile Adamts5 expression during mouse embryogenesis and in adult mouse tissues. Embryonic expression was scarce prior to 11.5 days of gestation (E11.5) and noted only in the floor plate of the developing brain at E9.5. After E11.5 there was continued expression in brain, especially in the choroid plexus, peripheral nerves, dorsal root ganglia, cranial nerve ganglia, spinal and cranial nerves, and neural plexuses of the gut. In addition to nerves, developing limbs have Adamts5 expression in skeletal muscle (from E13.5), tendons (from E16.5), and inter-digital mesenchyme of the developing autopod (E13.5–15.5). In adult tissues, there is constitutive Adamts5 expression in arterial smooth muscle cells, mesothelium lining the peritoneal, pericardial and pleural cavities, smooth muscle cells in bronchi and pancreatic ducts, glomerular mesangial cells in the kidney, dorsal root ganglia, and in Schwann cells of the peripheral and autonomic nervous system. Expression of Adamts5 during neuromuscular development and in smooth muscle cells coincides with the broadly distributed proteoglycan versican, an ADAMTS5 substrate. These observations suggest the major contexts in which developmental and physiological roles could be sought for this protease.

Characterization of proADAMTS5 processing by proprotein convertases.

ADAMTS5 (aggrecanase-2), a key metalloprotease mediating cartilage destruction in arthritis, is synthesized as a zymogen, proADAMTS5. We report a detailed characterization of the propeptide excision mechanism and demonstrate that it is a major regulatory step with unusual characteristics. Using furin-deficient cells and a furin inhibitor, we found that proADAMTS5 was processed by proprotein convertases, specifically furin and PC7, but not PC6B. Mutagenesis of three sites containing basic residues within the ADAMTS5 propeptide (RRR⁴⁶, RRR⁶⁹ and RRRRR²⁶¹) suggested that proADAMTS5 processing occurs after ^Arg261. That furin processing was essential for ADAMTS5 activity was illustrated using the known ADAMTS5 substrate aggrecan, as well as a new substrate, versican, an important regulatory proteoglycan during mammalian development. When compared to other ADAMTS proteases, proADAMTS5 processing has several distinct features. In contrast to ADAMTS1, whose furin processing products were clearly present intracellularly, cleaved ADAMTS5 propeptide and mature ADAMTS5 were found exclusively in the conditioned medium. Despite attempts to enhance detection of intracellular proADAMTS5 processing, such as by immunoprecipitation of total ADAMTS5, overexpression of furin, and secretion blockade by monensin, neither processed ADAMTS5 propeptide nor the mature enzyme were found intracellularly, which was strongly suggestive of extracellular processing. Extracellular ADAMTS5 processing was further supported by activation of proADAMTS5 added exogenously to HEK293 cells stably expressing furin. Unlike proADAMTS9, which is processed by furin at the cell-surface, to which it is bound, ADAMTS5 does not bind the cell-surface. Thus, the propeptide processing mechanism of ADAMTS5 has several points of distinction from those of other ADAMTS proteases, which may have considerable significance in the context of osteoarthritis.

Can a disease-specific education program augment self-management skills and improve Health-Related Quality of Life in people with hip or knee osteoarthritis?

Background: Patient education and self-management programs are offered in many countries to people with chronic conditions such as osteoarthritis (OA). The most well-known is the disease-specific Stanford Arthritis Self-Management Program (ASMP). While Australian and international clinical guidelines promote the concept of self-management for OA, there is currently little evidence to support the use of the ASMP. Several meta-analyses have reported that arthritis self-management programs had minimal or no effect on reducing pain and disability. However, previous studies have had methodological shortcomings including the use of outcome measures which do not accurately reflect program goals. Additionally, limited cost-effectiveness analyses have been undertaken and the cost-utility of the program has not been explored.

Methods/design: This study is a randomised controlled trial to determine the efficacy (in terms of Health-Related Quality of Life and self-management skills) and cost-utility of a 6-week group-based Stanford ASMP for people with hip or knee OA.

Six hundred participants referred to an orthopaedic surgeon or rheumatologist for hip or knee OA will be recruited from outpatient clinics at 2 public hospitals and community-based private practices within 2 private hospital settings in Victoria, Australia. Participants must be 18 years or over, fluent in English and able to attend ASMP sessions. Exclusion criteria include cognitive dysfunction, previous participation in self-management programs and placement on a waiting list for joint replacement surgery or scheduled joint replacement.

Eligible, consenting participants will be randomised to an intervention group (who receive the ASMP and an arthritis self-management book) or a control group (who receive the book only). Follow-up will be at 6 weeks, 3 months and 12 months using standardised self-report measures. The primary outcome is Health-Related Quality of Life at 12 months, measured using the Assessment of Quality of Life instrument. Secondary outcome measures include the Health Education Impact Questionnaire, Western Ontario and McMaster Universities Osteoarthritis Index (pain subscale and total scores), Kessler Psychological Distress Scale and the Hip and Knee Multi-Attribute Priority Tool. Cost-utility analyses will be undertaken using administrative records and self-report data. A subgroup of 100 participants will undergo qualitative interviews to explore the broader potential impacts of the ASMP.

Discussion: Using an innovative design combining both quantitative and qualitative components, this project will provide high quality data to facilitate evidence-based recommendations regarding the ASMP.

Focusing in on structural genomics : the University of Queensland structural biology pipeline

The flood of new genomic sequence information together with technological innovations in protein structure determination have led to worldwide structural genomics (SG) initiatives. The goals of SG initiatives are to accelerate the process of protein structure determination, to fill in protein fold space and to provide information about the function of uncharacterized proteins. In the long-term, these outcomes are likely to impact on medical biotechnology and drug discovery, leading to a better understanding of disease as well as the development of new therapeutics. Here we describe the high throughput pipeline established at the University of Queensland in Australia. In this focused pipeline, the targets for structure determination are proteins that are expressed in mouse macrophage cells and that are inferred to have a role in innate immunity. The aim is to characterize the molecular structure and the biochemical and cellular function of these targets by using a parallel processing pipeline. The pipeline is designed to work with tens to hundreds of target gene products and comprises target selection, cloning, expression, purification, crystallization and structure determination. The structures from this pipeline will provide insights into the function of previously uncharacterized macrophage proteins and could lead to the validation of new drug targets for chronic obstructive pulmonary disease and arthritis.

Guideline for the non-surgical management of hip and knee osteoarthritis

Introduction: Chronic disease is a major public health burden on Australian society. An increasing proportion of the population has risk factors for, or at least one, chronic disease, leading to increasing public health costs. Health service policy and delivery must not only address acute conditions, it must also effectively respond to the wide range of health and public service requirements of people with chronic illness.^1,2 Strong primary health care policy is an important foundation for a successful national health delivery system and long term management of public health, and is linked to practical outcomes including lower mortality, decreased hospitalisation and improved health outcomes.¹ National strategic health policy has recently given increased recognition to the importance of chronic disease management, with the Australian Federal Government endorsement of a number of initiatives for the prevention (or delay in onset), early detection and evidence based management of chronic disease, including osteoarthritis.^1,3
Chronic musculoskeletal conditions, including arthritis, account for over 4% of the national disease burden in terms of disability adjusted life years. Over 6 million Australians (almost one-third of the population) are estimated to have a chronic musculoskeletal disease; chronic musculoskeletal disease represents the main cause of long term pain and physical disability. In Australia, osteoarthritis is self reported by more than 1.4 million people (7.3% of the population4) and is the tenth most commonly managed problem in general practice.5 This number is set to rise as the elderly population grows. Osteoarthritis exerts a significant burden on the individual and the community through reduction in quality of life, diminished employment capacity and an increase in health care costs. For further details, refer to the Evidence to support the National Action Plan for Osteoarthritis, Rheumatoid Arthritis and Osteoporosis: Opportunities to improve health-related quality of life and reduce the burden of disease and disability (2004).⁶
As such, federal government health policy has identified arthritis as a National Health Priority Area and adopted a number of initiatives aimed at decreasing the burden of chronic disease and disability; raising awareness of preventive disease factors; providing access to evidence based knowledge; and improving the overall management of arthritis within the community.4 In 2002, all Australian health ministers designated arthritis and musculoskeletal conditions as Australia’s seventh National Health Priority Area. In response, a National Action Plan was developed in 2004 by the National Arthritis and Musculoskeletal Conditions Advisory Group (NAMSCAG).6 The aim of this document was to provide a blueprint for national initiatives to improve the health related quality of life of people living with osteoarthritis, rheumatoid arthritis and osteoporosis; reduce the cost and prevalence of these conditions; and reduce the impact on individuals, their carers and their communities within Australia. The National Action Plan was developed to complement both the National Chronic Disease Strategy – which is broader – and the National Service Improvement Framework for Osteoarthritis, Rheumatoid Arthritis and Osteoporosis, in addition to other national and state/ territory structures.

Reaching and influencing consumers in the prescription medicine market

Purpose – Celebrex became the first of a new class of drugs known as COX-2 selective non-steroidal anti-inflammatory drugs. It improves treatment for arthritis sufferers without compromising the protective lining of the stomach. The purpose of this paper is to illustrate how direct-to-consumer advertising (DTCA) of prescription medicines can be used to rebuild faith in the cyclooxygenase-2 (COX-2) product category.

Design/methodology/approach – The case is developed using published sources and no input is required from company representatives. The presentation style follows the classic comprehensive case format used in postgraduate teaching programmes.

Findings – Business executives and strategic marketing students would benefit from a discussion on how external environmental factors can suddenly impose a review of marketing strategy. The reader learns how management addresses the business dilemma using DTCA.

Research limitations/implications – A blockbuster rival drug Vioxx is withdrawn due to cardiovascular (CV) health safety concerns. A resulting dominant market situation soon becomes a business dilemma. The Federal Drug Administration calls for a “black box” warning label on Celebrex, the most serious type of warning.

Practical implications – The implications are that having a product in a class of its own is not enough. It highlights the need to communicate to different audiences, to both the medical profession and the end-user. Getting doctors to recommend the medicine and pulling the product through the channel by stimulating patient demand after a health scare are paramount.

Originality/value – This is the first pharmaceutical business case where the withdrawal of a rival product leaves the dominant competitor in a monopoly situation. Contrary to expectation, market share plummets despite the absence of competition.

Expanding evidence for the multiple dangers of epidemic abdominal obesity

The waistline of America has been expanding now for decades,1 largely as a consequence of an obesogenic environment, with a car-worshipping culture and take-away lifestyle par excellence.2 No upper limit to the prevalence or extent of obesity is yet apparent, and many countries and communities worldwide are busily following the American lead. Accumulating research evidence suggests that the personal and economic costs of the obesity epidemic are immense,3 driven by the obesity-related increases in risk for conditions such as type 2 diabetes mellitus, the metabolic syndrome, cardiovascular disease (CVD), kidney disease, arthritis, cancer, asthma, and sleep-disordered breathing. In addition, decreases are apparent in self-esteem and quality of life.