The Countess Margaret of Henneberg and Her 365 Children

According to an oBScure medieval legend, the Countess Margaret of Henneberg, a notable Dutch noblewoman, gave birth to 365 children in the year 1276. The haughty Countess had insulted a poor beggar woman carrying twins, since she believed that a pair of twins must have different fathers, and that their mother must be an adultress. She was punished by God, and gave birth to 365 minute children on Good Friday, 1276. The Countess died shortly after, together with her offspring, in the village of Loosduinen near The Hague. The Countess and her numerous brood were frequently described in historical and obstetrical works. To this day, a memorial tablet and two basins, representing those in which the 365 children were baptized, are to be seen in the church of Loosduinen.

The Earliest known Case of a Lithopaedion

A lithopaedion, or stone-child, is a dead fetus, usually the result of a primary or secondary abdominal pregnancy, that has been retained by the mother and subsequently calcified. This paper describes the earliest known case of this phenomenon. It was discovered in 1582, at the autopsy of a 68-year-old woman in the French city of Sens, and described in a thesis by the physician Jean d'Ailleboust. The woman had carried her lithopaedion for 28 years. In this historical vignette, the lithopaedion of Sens is compared to later instances of this phenomenon. The ultimate fate of the lithopaedion specimen, which was widely traded throughout Europe in the 1600s before finally ending up in Copenhagen, is traced.

The Hairy Family of Burma: A Four Generation Pedigree of Congenital Hypertrichosis Lanuginosa

A Burmese family with congenital hypertrichosis lanuginosa had an eventful history in the nineteenth century. The earlier members of this family were employed at the court of Ava, but the later ones spent their lives in show business, being widely exhibited for money in the 1880s. Their extraordinary hairiness attracted much curiosity, and they were photographed several times. The hairy Burmese are the only example of a four-generation pedigree of congenital hypertrichosis lanuginosa, which is consistent with an autosomal dominant mode of inheritance. There is good evidence that, when the members of this family were hairy, their dentition was also deficient.

Historical analysis of Newfoundland dog fur colour genetics

This article makes use of digitized historic newspapers to analyze Newfoundland dog fur colour genetics, and fur colour variations over time. The results indicate that contrary to the accepted view, the ‘Solid’ gene was introduced into the British population of Newfoundland dogs in the 1840s. Prior to that time, the dogs were white and black (Landseer) or white and brown, and thus spotted/spotted homozygotes. Due to ‘Solid’ being dominant over ‘spotted’, and selective breeding, today the majority of Newfoundland dogs are solid black. Whereas small white marks on the chest and/or paw appears to be a random event, the historical data supports the existence of an ‘Irish spotted’ fur colour pattern, with white head blaze, breast, paws and tail tip, in spotted/spotted homozygotes.

Historical analysis of Newfoundland dog fur colour genetics

This article makes use of digitized historic newspapers to analyze Newfoundland dog fur colour genetics, and fur colour variations over time. The results indicate that contrary to the accepted view, the 'Solid' gene was introduced into the British population of Newfoundland dogs in the 1840s. Prior to that time, the dogs were white and black (Landseer) or white and brown, and thus spotted/spotted homozygotes. Due to 'Solid' being dominant over 'spotted', and selective breeding, today the majority of Newfoundland dogs are solid black. Whereas small white marks on the chest and/or paw appears to be a random event, the historical data supports the existence of an 'Irish spotted' fur colour pattern, with white head blaze, breast, paws and tail tip, in spotted/spotted homozygotes.

The regulation of the ADAMTS4 and ADAMTS5 aggrecanases in osteoarthritis: a review

Destruction of articular cartilage is a key feature of a number of arthritides, osteoarthritis prominent among them. Aggrecan degradation, caused by increased activity of proteolytic enzymes that degrade macromolecules in the cartilage extracellular matrix, is followed by irreversible collagen degradation. The degradation of aggrecan is mediated by various matrix proteinases, mainly the aggrecanases, multidomain metalloproteinases belonging to the ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) family. There has been much interest in the possible role of these aggrecanases, mainly ADAMTS4 and ADAMTS5, as therapeutic targets in osteoarthritis. There is still debate which of them is the major aggrecanase in osteoarthritis, however, as well as major issues concerning how they are regulated, with possible discrepancies between murine models and results obtained using human osteoarthritis tissue. This review discusses some recent data regarding the regulation of ADAMTS4 and ADAMTS5 gene expression in osteoarthritis, with emphasis on the role of proinflammatory cytokines in driving these enzymes, and of the transcription factor NFkappaB in mediating their expression.

Interleukin-1beta induced activation of nuclear factor-kappab can be inhibited by novel pharmacological agents in osteoarthritis

OBJECTIVES

To investigate the importance of activation of the transcription factor, nuclear factor-kappaB (NF-kappaB) by interleukin-1beta (IL-1beta) and tumour necrosis factor-alpha (TNF-alpha) in the pathogenesis of osteoarthritis (OA) and assess its suitability as a target for therapy by determining its role in the induction of the cytokine IL-6 and the degenerative enzymes, matrix metalloproteinase (MMP)-1 and MMP-3 in vitro.

METHODS

Three distinct cellular models, derived from primary OA tissue, were employed, namely, fibroblast-like synoviocytes (OA-SF); co-cultures containing phenotypic macrophage-like and fibroblast-like cells (OA-COCUL); and primary OA synovial tissue explants (OA-EXP). These were treated with specific inhibitors of IL-1beta, TNF-alpha and NF-kappaB to assess their differential role in the production of pathologically relevant mediators, specifically IL-6, MMP-1, MMP-3 and the tissue inhibitor of metalloproteinases-1 (TIMP-1), which were quantified by enzyme-linked immunosorbent assay.

RESULTS

Inhibition of NF-kappaB by a novel agent, RO100 at a dose of 0.1 microM, exerted significant (P < 0.05) repression of IL-6, MMP-1 and MMP-3 production in OA-SF. Notably, neither TIMP-1 production nor cell viability was significantly affected at the dose tested. These data were reproduced in OA-EXP, which might be considered as having greater physiological relevance. Interestingly, comparable efficacy was noted using IL-1beta and TNF-alpha neutralizing antibodies in OA-COCUL.

CONCLUSIONS

We have demonstrated that a novel pharmacological inhibitor of NF-kappaB, RO100 inhibits pathological mediators of OA progression with equivalent efficacy as established IL-1beta and TNF-alpha neutralizing strategies. Our findings highlight a potential for developing NF-kappaB targeted therapeutics for positively regulating disease activity and improving clinical outcome in OA.

Adenoviral gene transfer into osteoarthritis synovial cells using the endogenous inhibitor IkappaBalpha reveals that most, but not all, inflammatory and destructive mediators are NFkappaB dependent

OBJECTIVES

Despite recent major advances in the understanding of the pathogenesis of rheumatoid arthritis, with tumour necrosis factor-alpha (TNFalpha) established as a major therapeutic target, comparatively little is known about the mediators involved in the destructive and inflammatory pathways in osteoarthritis (OA). Recently, it has become appreciated that an inflammatory synovitis contributes not only to the signs and symptoms of osteoarthritis, but also to disease progression. Here, we use high-efficiency adenoviral gene transfer to investigate the role of the transcription factor nuclear factor-kappaB (NFkappaB) in regulating inflammatory and destructive mediators in the late stage OA synovium.

METHODS

Infection with reporter adenoviruses transferring the beta-galactosidase or green fluorescent protein genes verified that OA synovial cells could be infected (>95%). Adenovirus transferring the inhibitory subunit IkappaBalpha inhibited NFkappaB. The production of a whole array of pro- and anti-inflammatory cytokines and mediators, and several matrix metalloproteinases and their main inhibitor, was measured by enzyme-linked immunosorbent assay.

RESULTS

The spontaneous production of macrophage-produced pro-inflammatory cytokines varied: TNFalpha was modestly inhibited by IkappaBalpha overexpression, but interleukin (IL)-1 was unaffected. Both IL-6 and IL-8 were potently inhibited, as were granulocyte-macrophage colony stimulating factor and oncostatin M. Anti-inflammatory mediators like IL-10, the IL-1 receptor antagonist and the p55 soluble TNF receptor were unaffected. Matrix metalloproteinases 1, 3, 9 and 13 were potently inhibited by IkappaBalpha overexpression, but not their main inhibitor tissue inhibitor of metalloproteinase-1.

CONCLUSIONS

The OA synovium is a highly inflammatory environment, with spontaneous production of many cytokines and matrix metalloproteinases. Inhibition of NFkappaB may have a beneficial effect on the balance between pro-inflammatory cytokines and anti-inflammatory mediators, and between destructive metalloproteinases and their main inhibitor.

Wegener’s granulomatosis mimicking a parotid abscess

We present the case of a previously healthy 59-year-old man who was under treatment for scleritis and episcleritis when he developed a parotid-gland swelling and pus-producing sinus. On surgical exploration, the features were those of a parotid abscess, but the lesion not only failed to heal post-operatively but increased in size very significantly. There was also severe necrotizing keratitis of the eyes. Due to clinical suspicion and a positive antineutrophil cytoplasmic antibodies test, Wegener’s granulomatosis was diagnosed and the patient successfully treated with cyclophosphamide and steroids. Previously, a number of cases of Wegener’s granulomatosis causing salivary-gland swelling have been reported in the literature; this is the first case in which the disease has masqueraded as a parotid abscess.

Antigen presentation by murine dendritic cells is nuclear factor-kappa B dependent both in vitro and in vivo

Antigen presentation is a key rate-limiting step in the immune response. Dendritic cells (DCs) have been reported to be the most potent antigen-presenting cells for naïve T cells, but little is known about the biochemical pathways that regulate this function. We here demonstrate that mature murine DC can be infected with adenovirus at high efficiency (>95%) and that an adenovirus transferring the endogenous inhibitor IkappaBalpha blocks nuclear factor-kappa B (NF-kappaB) function in murine DC. This result indicates that antigen presentation in the mixed leucocyte reaction is NF-kappaB dependent, confirming data with human DC in vitro. However, the importance of this finding depends on verifying that this is true also in vivo. Using delayed type hypersensitivity with allogeneic cells, we show that NF-kappaB inhibition had a marked immunosuppressive effect in vivo. These results thus establish NF-kappaB as an effective target for blocking DC antigen presentation and hence inhibiting T-cell-dependent immune responses. This finding has potential implications for the development of therapeutic agents for use in various pathological conditions of the immune system, including allergy and autoimmunity, and also in transplantation.

Antigen-specific T-cell downregulation by human dendritic cells following blockade of NF-kappaB

Dendritic cells (DCs) are important for presenting antigen to T cells, especially naïve T cells. It has recently been shown that blocking the transcription factor, nuclear factor kappa B (NF-kappaB) in human DCs inhibited the mixed leukocyte reaction. The aim of this study was to investigate the effect of blocking NF-kappaB in DCs during presentation of antigen to memory T cells in vitro. Peripheral blood monocytes were differentiated into immature DCs with interleukin-4 (IL-4) and granulocyte-macrophage colony-stimulating factor, and pulsed with an immunogenic tetanus toxoid peptide. Upon maturation, the antigen-pulsed DCs were highly effective in presenting antigen to autologous T cells. However, stimulation with antigen-pulsed DCs overexpressing IotakappaBetaalpha, the endogenous inhibitor of NF-kappaB, led to a significant reduction in T-cell proliferation, and decreased production of interferon-gamma, IL-4 and IL-10, whereas transforming growth factor-beta production was low throughout. There was a significant increase in apoptosis of antigen-specific T cells, even in the presence of IL-2, which was not found in resting T cells. Similar findings were observed using a proteasome inhibitor to block NF-kappaB. The effective downregulation of antigen-specific T-cell responses following blockade of NF-kappaB in DCs could be a useful approach for immunomodulating inflammatory T-cell responses.

Is NF-kappaB a useful therapeutic target in rheumatoid arthritis?

There is increasing evidence that NF-kappaB is a major, if not the major transcription factor regulating inflammation and immunity. While this implies that blocking NF-kappaB might be therapeutically beneficial, it raises clear questions regarding the balance between efficacy and safety. In this brief review we discuss the effects of NF-kappaB blockade in rheumatoid arthritis, inflammation and immunity, and consider possible therapeutic targets within the NF-kappaB family.

Cytokine blockade in rheumatoid arthritis

As we enter the 2000's it is clear that cytokine blockade is an effective therapeutic strategy for rheumatoid arthritis. In this brief review, we will review the rationale for anti TNFalpha therapy, the current status of therapy and focus on the regulation of TNFalpha production in rheumatoid synovium. New approaches to studying TNF regulation in RA and of elucidating the controversial role of T cells in this complex disease will be described.

High efficiency gene transfer is an efficient way of defining therapeutic targets: a functional genomics approach

BACKGROUND

Dendritic cells are the most potent antigen presenting cells and key to many aspects of the immune function. Studying the intracellular signalling mechanism used by dendritic cells would provide an insight into the functioning of these cells and give clues to strategies for immunomodulation.

METHOD

Highly efficient adenoviral infection of dendritic cells for the delivery of transgenes was obtained. These viral vectors were used to introduce IkappaB alpha into dendritic cells for the inhibition of NF-kappaB. This was used to investigate the role of NF-kappaB in dendritic cell function.

RESULTS

By blocking the NF-kappaB function a potent inhibition of the expression of costimulating molecules by dendritic cells with the concomitant loss of T cell stimulating function was demonstrated.

CONCLUSION

The use of adenoviral vectors may be a useful way of studying the role of genes in dendritic cell function.

Dicephalus conjoined twins: a historical review with emphasis on viability

Dicephalus conjoined twins (2 heads on 1 body) form a distinct subgroup. They are often stillborn because of cardiopulmonary malformations. This article describes 17 historical cases with particular emphasis on viability. There are reliable reports of unseparated dicephali reaching maturity; 1 pair (the Tocci brothers) reached at least 34 years of age. In the absence of concomitant cardiac, pulmonary, and intestinal malformations, dicephalus conjoined twins may well attain adulthood. This appears to be unrelated to whether they have 4 (dicephalus tetrabrachius) or 3 (dicephalus tribrachius) arms at birth.

Alveolar macrophages and T cells from sarcoid, but not normal lung, are permissive to adenovirus infection and allow analysis of NF-kappa b-dependent signaling pathways

Adenovirus (Adv)-mediated gene transfer requires efficient infection of target cells. The objective of this study was to establish whether alveolar macrophages (AM) and T cells (AT) from sarcoid patients were permissive to infection with Adv vectors and if this property could be used to investigate cytokine gene regulation. Sarcoid and normal bronchoalveolar lavage (BAL) specimens infected with Adv vectors expressing either beta-galactosidase or a green fluorescent protein were analyzed for transgene expression by fluorescence-activated cell sorter (FACS) and direct immunofluorescence, respectively. Expression of surface antigens previously associated with Adv infection, the coxsackie/adenovirus receptor (CAR), alpha v beta 3, and alpha v beta 5 integrins, was also assessed using FACS analysis. Sarcoid AM and AT were found to efficiently express Adv transgenes, unlike AM from normal volunteers, peripheral blood monocytes, and peripheral blood T cells. Cells permissive to Adv infection expressed the CAR and alpha v beta 5 integrin (also alpha v beta 3 integrin for AM). The data indicate that the upregulation of Adv receptors and the ability to infect sarcoid AM and AT are related to the inflammatory environment within the lung. Having demonstrated efficient Adv-mediated transgene delivery to sarcoid AM and AT, a construct encoding porcine I kappa B alpha was then used to investigate the requirement for nuclear factor (NF)-kappa B in the regulation of cytokine gene expression in pulmonary sarcoidosis. Overexpression of I kappa B alpha in sarcoid BAL specimens indicated that tumor necrosis factor-alpha and interleukin (IL)-6 production by AM and interferon (IFN)-gamma production by AT is NF-kappa B dependent, whereas IL-4 production by AT is NF-kappa B independent. This is the first occasion that the requirement for NF-kappa B in IFN-gamma gene expression within primary human T cells has been demonstrated. The results of this study have implications for the future investigation of molecular pathways in inflammatory lung disease.

Everard Home, John Hunter, and cutaneous horns: a historical review

A cutaneous horn is a protrusion from the skin made up of cornified material. These horns can be derived from a variety of epidermal lesions, both benign and malignant. This historical article reviews a number of early instances of cutaneous horns, some reported in the 16th and 17th centuries. The Danish anatomist Thomas Bartholin was the first to have a correct theory of the ethiology of these horny growths, and the English surgeons John Hunter and Everard Home confirmed his findings in the late 18th century.

Role of NFkappaB in antigen presentation and development of regulatory T cells elucidated by treatment of dendritic cells with the proteasome inhibitor PSI

Dendritic cells (DC) are the most potent antigen-presenting cells for naive T cells, due to their high expression of MHC and costimulatory molecules, but relatively little is known about the biochemical pathways that regulate this function. We used the proteasome inhibitor N-benzyloxycarbonyl-Ile-Glu(O-tert-butyl)-Ala-leucinal (PSI) to demonstrate that DC antigen presentation is NFkappaB dependent. As PSI is not a specific inhibitor of NFkappaB, we reproduced this finding using a very specific approach, namely adenoviral gene transfer of IkappaBalpha, the naturally occurring inhibitor of NFkappaB. The mechanism for this inhibition of DC antigen presentation involves at least three aspects of antigen presenting function: down-regulation of HLA class II, down-regulation of CD86, and inhibition of the immunostimulatory cytokines IL-12 and TNF-alpha. In the light of the marked down-regulation of antigen-presentation cell function, it was of interest to investigate what effects exposure to PSI-treated DC might have on T cell function. It was found that immunological tolerance was induced, as challenge of T cells previously exposed to PSI-treated DC, with normal DC from the same donor did not restore their response, despite the presence of viable T cells. There were also changes in T cell surface markers, with down-regulation of CD3 and CD25 expression, and inhibition of the production of Th1 cytokines like IL-2 and IFN-gamma. These results demonstrates that NFkappaB is an effective target for blocking DC antigen presentation and inhibiting T cell-dependent immune responses, and this has implications for the development of therapeutic agents for use in multiple conditions, including transplantation, allergy and autoimmune diseases.

Effective antigen presentation by dendritic cells is NF-kappaB dependent: coordinate regulation of MHC, co-stimulatory molecules and cytokines

Antigen presentation is a key rate-limiting step in the immune response. Dendritic cells (DC) are the most potent antigen-presenting cells for naive T cells, due to their high expression of MHC and co-stimulatory molecules, but little is known about the biochemical pathways that regulate this function. We here demonstrate that monocyte-derived mature DC can be infected with adenovirus at high efficiency (>95%) and that this procedure can be used to dissect out which pathways are essential for inducing DC antigen presentation to naive T cells. Using adenoviral transfer of the endogenous inhibitor of NF-kappaB, IkappaBalpha, we show that DC antigen presentation is NF-kappaB dependent. The mechanism for this is that NF-kappaB is essential for three aspects of antigen-presenting function: blocking NF-kappaB coordinately down-regulates HLA class II, co-stimulatory molecules like CD80, CD86 and CD40, and immuno-stimulatory cytokines like IL-12 and tumor necrosis factor-alpha. In contrast adhesion molecules are up-regulated after infection with the adenovirus transferring IkappaBalpha, indicating that NF-kappaB also regulates the duration of T cell-DC interaction. These results establish NF-kappaB as an effective target for blocking DC antigen presentation and inhibiting T cell-dependent immune responses, and this finding has potential implications for the development of therapeutic agents for use in allergy, autoimmunity and transplantation.

Tumour necrosis factor as a therapeutic target in rheumatoid arthritis and other chronic inflammatory diseases: the clinical experience with infliximab (REMICADE)

Therapeutic strategies that aim to neutralise the important pro-inflammatory cytokine tumour necrosis factor alpha (TNF alpha) have gained considerable prominence in the therapy of chronic inflammatory diseases, notably rheumatoid arthritis and Crohn's disease. This drug focus review will concentrate on the antitumour necrosis factor antibody infliximab (Remicade), which has been approved for the treatment of rheumatoid arthritis and Crohn's disease in both the US and Europe. In addition, infliximab is under investigation for several other indications, mainly inflammatory rheumatic diseases. Clinical trials have been persuasive that infliximab is both safe and effective, and it has been proven to be far superior to the conventional drug therapy in both rheumatoid arthritis and Crohn's disease. Remarkably, infliximab in combination with methotrexate controls both the inflammatory joint symptoms and the progression of joint damage, which renders it a very attractive therapeutic option in moderate to severe, therapy-resistant rheumatoid arthritis.

Adenoviral transgene delivery provides an approach to identifying important molecular processes in inflammation: evidence for heterogenecity in the requirement for NFkappaB in tumour necrosis factor production

The success of anti-tumour necrosis factor (TNF) treatment, either using antibodies or soluble receptors, has defined TNF as a major factor of the inflammatory response in rheumatoid arthritis (RA). As a result of this success, much attention has been devoted to understanding the molecular mechanisms by which TNF expression and activity is elicited and controlled. By understanding these pathways, it is hoped that key elements of the molecular pathology associated with RA will be uncovered and, as a result, new targets for therapeutic intervention will be identified. However, studying the cell and molecular biology of model systems for RA, such as primary human macrophages, or tissue from rheumatoid joints may present technical problems. In an attempt to overcome this, we have investigated the use of adenovirus as a means of delivering transgenes by which different intracellular pathways can be modulated and examined. Our data show that adenovirus can be successfully used to efficiently deliver transgenes to primary human macrophages and RA joint tissue. Using a virus encoding IkappaBalpha, the natural inhibitor of NFkappaB, we show that the requirement for the transcription factor is not universal, but is dependent on the nature of the stimulus. Furthermore, while NFkappaB is of importance for the expression of TNF and other pro-inflammatory cytokines (for example, interleukin 6) and the destructive matrix metalloproteinases, this factor is not required for the expression of anti-inflammatory cytokines interleukin 10 and interleukin 1 receptor antagonist.

Effective adenoviral transfer of IkappaBalpha into human fibroblasts and chondrosarcoma cells reveals that the induction of matrix metalloproteinases and proinflammatory cytokines is nuclear factor-kappaB dependent

OBJECTIVE

To determine whether, in human fibroblasts and chondrosarcoma cells, the regulation of interleukins (IL)-6, 8, and 11 and matrix metalloproteinases (MMP)-1, 3, and 13, and their tissue inhibitor TIMP-1, depends on the transcription factor nuclear factor-kappaB (NF-kappaB).

METHODS

Fibroblasts and chondrosarcoma cells were effectively infected with an adenovirus encoding human IkappaBalpha, and inhibition of NF-kappaB function was observed. The induction of MMP and IL-6, 8, and 11 by various stimuli was assessed by ELISA.

RESULTS

The induction of IL-6 and IL-8 clearly depended on NF-kappaB in both fibroblasts and chondrosarcoma cells, irrespective of stimulus, but IkappaBalpha overexpression had little effect on IL-11. MMP-1, -3, and -13 were also inhibited, but TIMP-1 was unaffected.

CONCLUSION

NF-kappaB appears to play an important and selective role in MMP induction in human fibroblasts and chondrosarcoma cells. This suggests there are NF-kappaB dependent mechanisms of cartilage destruction in rheumatoid arthritis, and supports the concept that there are similarities in the regulation of inflammatory and destructive pathways in that disease.

The rationale for the current boom in anti-TNFalpha treatment. Is there an effective means to define therapeutic targets for drugs that provide all the benefits of anti-TNFalpha and minimise hazards?

Progress in understanding mechanisms of disease are necessary to usher in major changes in treatment. A new era in rheumatoid arthritis (RA) and related chronic autoimmune/inflammatory diseases is now beginning, with a variety of anti-TNFalpha treatments licensed for use in both RA and Crohn's disease. The rationale for this new treatment lies in an understanding that cytokines are critical, rate limiting molecules lying at the heart of the chronic autoimmune/inflammatory disease process. This understanding was developed from the critical evaluation of a hypothesis that was proposed linking cytokines, antigen presentation and autoimmunity in 1983. Detailed analysis focusing on the major site of the disease, the rheumatoid synovium was essential to developing indications that blockade of TNFalpha might be efficacious. This clue was validated using anti-TNFalpha treatment of an animal model of RA, murine collagen induced arthritis, and by immunohistochemical demonstration of upregulated TNF and TNF-R expression in the synovium. With this three pronged rationale, the authors were able to convince Centocor, Inc, which had developed a chimaeric anti-TNFalpha antibody for use in sepsis, to work with them to test the concept that TNFalpha blockade would be beneficial in RA. With the success of that first trial, other companies have subsequently tested their anti-TNF strategies successfully. Current interests extend to understanding the processes that regulate TNF production in the rheumatoid joint. Progress in this area is discussed, using adenoviruses to infect normal macrophages and rheumatoid synovium.

Defining therapeutic targets by using adenovirus: blocking NF-kappaB inhibits both inflammatory and destructive mechanisms in rheumatoid synovium but spares anti-inflammatory mediators

The role of the transcription factor NF-kappaB in the pathogenesis of rheumatoid arthritis has long been a subject of controversy. We used an adenoviral technique of blocking NF-kappaB through overexpression of the inhibitory subunit IkappaBalpha, which has the advantage that it can be used in the diseased tissue itself, with >90% of the synovial macrophages, fibroblasts, and T cells infected. We found that the spontaneous production of tumor necrosis factor alpha and other pro-inflammatory cytokines is NF-kappaB-dependent in rheumatoid synovial tissue, in contrast to the main anti-inflammatory mediators, like IL-10 and -11, and the IL-1 receptor antagonist. Of even more interest, IkappaBalpha overexpression inhibited the production of matrix metalloproteinases 1 and 3 while not affecting their tissue inhibitor. Blocking NF-kappaB in the rheumatoid joint thus has a very beneficial profile, reducing both the inflammatory response and the tissue destruction. The adenoviral technique described here has widespread applicability, allowing rapid testing of the effects of blocking a potential therapeutic target in either cultures of normal cells or in the diseased tissue itself.

Selective regulation of cytokine induction by adenoviral gene transfer of IkappaBalpha into human macrophages: lipopolysaccharide-induced, but not zymosan-induced, proinflammatory cytokines are inhibited, but IL-10 is nuclear factor-kappaB independent

Macrophages are the major cytokine producers in chronic inflammatory diseases, but the biochemical pathways regulating cytokine production are poorly understood. This is because genetic tools to dissect signaling pathways cannot be used in macrophages because of difficulties in transfection. We have developed an adenoviral technique to achieve high efficiency gene delivery into macrophages and recently showed that spontaneous TNF-alpha production in rheumatoid arthritis joint cells, chiefly from macrophages, is 75% blocked by adenoviral transfer of IkappaBalpha. In this report we use the same adenovirus to investigate whether the production of a number of proinflammatory cytokines (e.g., TNF-alpha, IL-1beta, IL-6, and IL-8) from human macrophages depends on NF-kappaB. While the cytokine response to certain inducers, such as LPS, PMA, and UV light, is blocked by overexpression of IkappaBalpha, the response to zymosan is not. In contrast, anti-inflammatory mediators (IL-10 and IL-1 receptor antagonist) induced by LPS are only marginally inhibited by IkappaBalpha excess. These studies demonstrate several new points about macrophage cytokine production. First, there is heterogeneity of mechanisms regulating both the proinflammatory and anti-inflammatory cytokines within populations of a single cell type. In addition, the results confirm the utility of the adenoviral technique for functional analysis of cytokine induction. The results also confirm that there are autocrine and paracrine interactions regulating cytokine synthesis within a single cell type. The selectivity of NF-kappaB blockade for proinflammatory but not anti-inflammatory mediators indicates that in macrophages, NF-kappaB may be a good target for the treatment of chronic inflammatory diseases.

The bosom serpent

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Efficient adenoviral infection with IkappaB alpha reveals that macrophage tumor necrosis factor alpha production in rheumatoid arthritis is NF-kappaB dependent

Tumor necrosis factor (TNF) alpha has been shown to be a major therapeutic target in rheumatoid arthritis with the success of anti-TNFalpha antibody clinical trials. Although signaling pathways leading to TNFalpha expression have been studied in some detail, there is evidence for considerable differences between individual cell types. This prompted us to investigate the intracellular signaling pathways that result in increased TNFalpha synthesis from macrophages in the diseased synovial joint tissue. Using an adenoviral system in vitro we report the successful delivery of genes to more than 95% of normal human macrophages. This permitted us to show, by using adenoviral transfer of IkappaB alpha, the natural inhibitor of NF-kappaB, that induction of TNFalpha in normal human macrophages by lipopolysaccharide, but not by some other stimuli, was inhibited by 80%. Furthermore the spontaneous production of TNFalpha from human rheumatoid joint cell cultures was inhibited by 75%, indicating that the NF-kappaB pathway is an essential step for TNFalpha synthesis in synovial macrophages and demonstrating that NF-kappaB should be an effective therapeutic target in this disease.

Phthiriasis: the riddle of the lousy disease

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Antimalarial drugs inhibit phospholipase A2 activation and induction of interleukin 1beta and tumor necrosis factor alpha in macrophages: implications for their mode of action in rheumatoid arthritis

1. The effects of antimalarial drugs on the intracellular signaling leading to activation of the phospholipase C and phospholipase A2 pathways and the induction of proinflammatory cytokines have been studied in mouse macrophages. 2. Both chloroquine and quinacrine, and to a lesser extent hydroxychloroquine, inhibited arachidonate release and eicosanoid formation induced by phorbol diester. This inhibition was due to that of the activation of the arachidonate-mobilizing phospholipase A2. 3. All three antimalarials potently inhibited arachidonate release induced by zymosan. They also inhibited the zymosan-induced formation of inositol phosphates, which hints that an inhibitory effect at the phospholipase C level might explain the inhibition of the response to zymosan. 4. Quinacrine, and to a lesser extent chloroquine, has an inhibitory effect on the lipopolysaccharide- or zymosan-induced expression of interleukin 1beta and tumor necrosis factor alpha, both at the mRNA and protein levels. This, in particular, has important implications for the mode of action of these compounds in rheumatoid arthritis.

Polymyositis associated with asymptomatic primary biliary cirrhosis

We here describe a case of polymyositis associated with asymptomatic primary biliary cirrhosis and a high titer of antimitochondrial antibodies. The patient had remarkable multiorgan engagement: polyarthritis, pericarditis, pleuritis and tachyarrythmia. Atypical changes, suggestive of mitochondrial damage, were observed in a muscle biopsy specimen. Under treatment with azathioprine and steroids, the disease had a favourable outcome.

Giant cell arteritis presenting with oculomotor nerve palsy

We present a case of histologically proven giant cell arteritis presenting as an acute unilateral oculomotor nerve palsy without pupillary dilatation. The etiology and mechanisms involved in this uncommon phenomenon are discussed. It is emphasized that a giant cell arteritis with cranial nerve involvement is a medical emergency, and that swift diagnosis and treatment is necessary to avoid permanent disability.

The mechanisms of action of disease-modifying antirheumatic drugs: a review with emphasis on macrophage signal transduction and the induction of proinflammatory cytokines

1. Rheumatoid arthritis (RA) is probably the most common source of treatable disability. A major problem in modern rheumatology is that the mechanism(s) of action of the currently used disease-modifying antirheumatic drugs (DMARDs) remain unclear. Many of these drugs entered rheumatology mainly through clinical intuition and have been used for decades. 2. The former T-cell-centered paradigm of rheumatoid inflammation has given way to a model of inflammation highlighting the macrophage and its proinflammatory cytokines. In particular, tumor necrosis factor alpha (TNF-alpha) has gained prominence as a central proinflammatory mediator in RA, and antibodies against TNF-alpha have been successfully used in patients with RA. 3. This review will summarize the recent advances in determining the mechanisms of action of the currently used DMARDs, with particular emphasis on their effects on the induction of TNF-alpha and interleukin 1 (IL-1) in mononuclear phagocytes. Although some DMARDs, such as auranofin, antimalarials and tenidap, act as inhibitors of the induction of these cytokines in monocytes or macrophages or both, other drugs, such as methotrexate, D-penicillamine and aurothiomalate, do not seem to affect either TNF-alpha or IL-1. 4. The drugs' effects on proinflammatory cytokine induction are correlated to those on other macrophage responses.