99mTc-labelled glucosamine in the assessment of systemic sclerosis inflammatory lung disease: a novel inexpensive investigative tool with predictive value

OBJECTIVE

To evaluate the role of ^99mTc-labelled glucosamine [^99mTc-ECDG] as a clinical biomarker for the early detection of interstitial lung disease (ILD) in systemic sclerosis (SSc).

METHODS

In this prospective pilot study, glucosamine scanning (GS) was performed in 15 SSc patients, with and without ILD. Collected data included patient disease characteristics, autoantibody profile, GS results, high-resolution computerised tomography [HRCT], pulmonary function tests [PFT], and transthoracic echocardiogram [TTE]. Glucosamine results were correlated with patient clinical profile, HRCT, and PFT's findings.

RESULTS

Lung uptake of ^99mTc-ECDG was high in 4 patients, moderate in 3, mild in 5, and normal in 3 with SSc, respectively. Of the patients with high and moderate uptake there was a 100% correlation between ^99mTc-ECDG uptake and HRCT showing ILD. Of the 5 patients with mild ^99mTc-ECDG uptake, 4 patients had aspiration pneumonia, and 1 had early ILD using HRCT. Of the 3 patients with normal ^99mTc-ECDG, 2 had normal HRCTs; the third had severe pulmonary arterial hypertension with minimal HRCT changes of ILD. High and moderate ^99mTc-ECDG lung uptake predicted abnormal PFT's in 100% of cases. In 3 patients, there was less extensive disease depicted on the ^99mTc-ECDG scans than on the HRCT. These patients demonstrated a more favourable outcome than would have been expected from the HRCT scans alone. Mild ^99mTc-ECDG lung uptake correlated with abnormal PFT's in 60% of cases. The pattern of ^99mTc-ECDG uptake was excellent (100%) at distinguishing metabolically active ILD from aspiration pneumonia. Diffuse uptake was noted in the former and patchy uptake in the latter disease entity.

CONCLUSION

Increased ^99mTc-ECDG uptake in scleroderma lung correlated positively with both structural and functional changes. ^99mTc-ECDG is a useful adjunct helping elucidate inflammation secondary to aspiration pneumonia and/or other causes of abnormal PFT's.

The motherhood choices decision aid for women with rheumatoid arthritis increases knowledge and reduces decisional conflict: a randomized controlled trial

BACKGROUND

For many women with Rheumatoid Arthritis (RA) motherhood decisions are complicated by their condition and complex pharmacological treatments. Decisions about having children or expanding their family require relevant knowledge and consultation with their family and physician as conception and pregnancy has to be managed within the RA context. Relevant information is not readily available to women with RA. Therefore a randomized controlled study was conducted to evaluate the effectiveness of a new motherhood decision aid (DA) developed specifically for women with RA.

METHODS

One hundred and forty-four women were randomly allocated to either an intervention or control group. All women completed a battery of questionnaires at pre-intervention, including, the Pregnancy in Rheumatoid Arthritis Questionnaire (PiRAQ), the Decisional Conflict Scale (DCS), the Hospital Anxiety and Depression Scale (HADS), and the Arthritis Self-Efficacy Scale (ASES), and provided basic demographic information. Women in the DA group were sent an electronic version of the DA, and completed the battery of questionnaires for a second time post-intervention.

RESULTS

Women who received the DA had a 13 % increase in relevant knowledge (PiRAQ) scores and a 15 % decrease in scores on the decisional conflict (DCS), compared to the control group (1 %, 2 % respectively). No adverse psychological effects were detected as evident in unchanged levels of depression and anxiety symptoms.

CONCLUSIONS

The findings of this study suggest that this DA may be an effective tool in assisting women with RA when contemplating having children or more children.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry, http://www.anzctr.org.au/ , ACTRN12615000523505.

Acute gross painless transudative ascites in a patient with lupus

Gross ascites is a rare presentation of lupus. Ascites in lupus may be due to lupus peritonitis or secondary to one of the complications including nephrotic syndrome. The ascites due to lupus peritonitis has been described as exudative with a serum-ascites albumin gradient (SAAG) below 11 g/L, unless associated with nephrotic syndrome. We report an unusual case of lupus ascites in a 23-year-old woman who presented with acute painless gross ascites with no constitutional, skin or musculoskeletal symptoms of a lupus flare. The ascites was a transudate with SAAG above 11 g/L with no associated nephrotic syndrome. She was treated with corticosteroids, mycophenolate mofetil and diuretics with a good response and no recurrence of her ascites.

Targeting fibroblast-like synovial cells at sites of inflammation with peptide targeted liposomes results in inhibition of experimental arthritis

In this study we examined a synovium-specific targeted liposomal drug delivery system for its ability to localize and release its drug cargo to inflamed joints. Targeted liposomes were tested in vitro for binding to synovial fibroblast like (FLS) and endothelial cells using flow cytometry and in vivo for localization to joints using a rat model of adjuvant induced arthritis (AIA). Targeted liposomes were then loaded with anti-arthritic medications and examined for clinical efficacy in AIA. Targeted liposomes specifically bound to rabbit FLS and human FLS and showed a 7-10 fold increase in vivo localization in affected joints compared to unaffected joints. Histological sections from rats treated with prednisone and a new immunosuppressive peptide CP showed minimal inflammation. This report substantiates the ability of the novel FLS sequence to target liposomal drug delivery and offers an alternative therapeutic approach for the treatment of arthritis.

Navigating motherhood choices in the context of rheumatoid arthritis: women's stories

OBJECTIVE

Planning a family is a complex decision. For women with chronic conditions such as rheumatoid arthritis (RA), there are additional concerns about their own and their baby's health. This qualitative study examined women's experiences of negotiating their family decisions in the context of RA.

METHODS

A qualitative study was conducted in 14 women who provided a written account of their motherhood decisions and experiences. Those 'stories' were then thematically analysed.

RESULTS

RA was found to affect women's motherhood decisions and experiences. Three key themes were identified for both the process of decision making and the experience of that decision: capacity, uncertainty and acceptance. Only two of the women decided not to have children, while for others the decision centred on changing expectations from the number of children they planned to have, to parenting within the restrictions of their physical abilities.

CONCLUSION

While many women struggled through the negotiations of their motherhood choices, those who chose to have children reported great joy in that experience. The challenges faced by women with RA contemplating motherhood, however, highlight the need for understanding and support from health professionals and the provision of resources so that women can make informed choices.

Antitopoisomerase antibody positivity predates nailfold capillaroscopy abnormalities in scleroderma. Postulated classification of 'prescleroderma'

In a patient with early topoisomerase antibody-positive scleroderma, antinuclear antibody positivity was fortuitously observed to predate nailfold capillaroscopy changes. Using this case as a template, the prediagnostic phase of the presumed multifactorial disease may be divided into 5 temporal phases--phase 1 representing conception and intrauterine environment, phase 2 representing the extrauterine environment predating environmental exposure; phase 3 representing the early post-environmental exposure interval with no detectable perturbed body status; phase 4 representing the post-environmental exposure interval characterized by autoantibody production and microvascular changes, and phase 5, the symptomatic clinical prediagnostic interval (Raynaud's, skin, musculoskeletal, gastrointestinal, cardiorespiratory) prompting scleroderma diagnosis. Temporal classification of prescleroderma aids in both the understanding and definition of scleroderma 'onset'. If altered nailfold capillaries and autoantibodies develop at comparable rates, and if the findings from this case--that autoantibody changes precede microvascular changes--are truly representative of the preclinical disease phase, then these findings argue that the evolution of the disease is from within the vessel outwards, rather than vice versa.

New onset sarcoid-like granulomatosis developing during anti-TNF therapy: an under-recognised complication

Tumour necrosis factor-alpha (TNF-a) antagonists have advanced the treatment of inflammatory arthropathies, and are even considered for use in refractory sarcoidosis with some success. Paradoxically, cases of new onset sarcoidosis-like diseases are increasingly reported in patients receiving TNF-a antagonists. Here, we report three cases of sarcoid-like granulomatosis that developed during treatment with TNF-a antagonists. Review of the Biologics clinic data base at Westmead, Sydney, Australia identified three patients whom, during anti-TNF therapy, developed non-caseating granulomas consistent with sarcoidosis. These three cases are described with review of the literature from 2000 to 2009 using PubMed. One hundred and sixty-nine patients within our data base were reviewed for the period 2003–2009. Sarcoidosis-like granulomas developed in three patients within a period of 3 to 36 months of treatment with etanercept and/or adalimumab. All cases demonstrated non-infective, non-caseating granulomas on renal or lymph node biopsy. Improvement was seen in two cases upon cessation of TNF-a antagonist and steroid therapy. Interestingly, clinical deterioration was noted upon re-challenge with the same TNF-a antagonist in one patient. To date, a total of 37 cases of sarcoid-like granuloma development after anti-TNF therapy have been reported in the literature. Development of sarcoidosis-like granulomatosis in patients treated with TNF-a antagonists is a phenomenon previously under-recognised. All three anti-TNF agents have been observed to cause this phenomenon, suggesting a ‘class effect’ rather than being drug specific.

P2X7 gene polymorphisms do not appear to be a susceptibility gene locus in sporadic cases of systemic lupus erythematosus

The P2X(7) receptor is a ligand-gated cation-selective channel that mediates ATP-induced apoptosis of cells of the immune system. A loss-of-function single nucleotide polymorphism (SNP) at position 1513 (1513 A-->C) of the P2X(7) gene has recently been identified in both healthy and chronic lymphocytic leukemia (CLL) B-cells, translating into a loss of P2X(7)-mediated apoptosis in these cells. This antiapoptotic effect results in increased B-cell numbers, thereby potentially contributing to the survival of B-CLL clones. It was hypothesized that prolonged cell survival may also predispose to induction of autoimmunity. The objective of this study is to analyze the role of the P2X(7) receptor and its loss-of-function 1513 A-->C polymorphism (SNP) in the development of systemic lupus erythematosus (SLE). DNA samples obtained from patients with sporadic SLE were analyzed for the presence of the 1513 A-->C polymorphism using polymerase chain reaction (PCR) amplification and then direct sequencing. No significant difference in allele frequencies (1513 A-->C polymorphism) between sporadic cases of SLE and controls was found. A loss-of-function SNP at position 1513 (1513 A-->C) of the P2X(7) gene does not appear to be a susceptibility gene locus for the development of sporadic SLE.

Lack of increased expression of cell surface markers for circulating fibrocyte progenitors in limited scleroderma

The aetiology and pathogenesis of scleroderma is incompletely understood. Recently, a cell called the fibrocyte has been shown to be derived from circulating monocytes with the ability to produce collagen. The aim of this study was to evaluate differences in the cell surface characteristics of circulating fibrocyte progenitors (monocytes) in patients with limited scleroderma compared to controls. A case-control study was performed in eight patients with limited scleroderma, which were matched with eight controls. Three-colour flow cytometry was used to assess the relative expression of cell surface markers. Statistical analysis then compared the relative expression between the two groups. In this preliminary study, there were no significant differences in the expression of circulating monocyte surface molecules involved with cell transformation, function, or migration presumed to give rise to fibrocytes, in a population of patients with limited scleroderma. Various explanations for the results are discussed.

Discrepancy in CD3-Transmembrane Peptide Activity between In Vitro and In Vivo T-Cell Inhibition

Electrostatic amino acid interactions between receptor subunits within the T-cell antigen receptor (TCR) transmembrane domain are critical for the formation of the TCR-CD3 complex. Core peptide, a short peptide corresponding to the TCR-alpha transmembrane region, containing two positively charged amino acids, is known to inhibit T-cell function in vitro and in vivo. The aim of this study was to examine peptides corresponding to the syntactic transmembrane CD3 region binding to TCR-alpha for their ability to inhibit T-cell activation in vitro and in vivo. Three peptides matching the transmembrane sequence of CD3-delta, -epsilon and -gamma were synthesized and tested in different biological in vitro and in vivo systems for their effect on T-cell activity. The CD3-peptides had no impact on T-cell function in vitro, but surprisingly, decreased signs of inflammation in the adjuvant arthritis rat model in vivo. Preliminary evidence suggests that peptides with CD3 transmembrane-derived sequences can inhibit an immune response as assessed by adjuvant-induced arthritis. The lack of in vitro activity may lead to a wasteful disregard of active compounds in the process of drug discovery and development.

Histiocytosis and bone: experience from one major Sydney teaching hospital

Langerhans cell histiocytosis (LCH) has diverse presentations which can bring it before all physicians regardless of specialty. A retrospective audit was undertaken at Westmead Hospital, Sydney, Australia, to ascertain the incidence, epidemiology and clinical features of patients with LCH over a 10-year period (1994-2004). A total of 12 patients was identified (six male, six female). Eleven patients had involvement of the skeletal system, three of the patients had pulmonary LCH and only one patient presented with soft tissue involvement (nose and antrum). Three patients had diabetes insipidus. Our results are consistent with that noted in the published literature and confirm the low incidence, diverse nature of presentation and the differing treatment strategies available for this rare and yet interesting condition.

Systemic scleroderma: a spatiotemporal clustering

BACKGROUND AND AIMS

The aetiology of systemic scleroderma remains poorly understood. Twin studies suggest a low genetic input. Of the incriminated environmental agents, silica and vinyl chloride monomer exposure appear the most convincing. Spatiotemporal clustering has been demonstrated only three times previously. We now report a fourth cluster around Edenhope, western Victoria in terms of numerator and denominator estimates, cumulative incidence, distribution in time and space, and possible aetiological factors.

METHODS

Prevalence/cumulative incidence numerator and denominator values were obtained and validated. Each case was age-and gender-matched with two controls. A standardized postal questionnaire was used to obtain data on current, past history, family history, and occupational and non-occupational environmental exposure.

RESULTS

Six systemic scleroderma cases and one mixed connective tissue disease patient with a predominance of scleroderma features were identified. The 5-year cumulative incidence was 6.1/10,000, tenfold higher than the Sydney estimates for a similar, though non-identical time period. The gender ratio was 1:1. No cases were genetically related. A family history of scleroderma was validated in one instance and a family history of Raynaud's was noted in first degree relatives of two cases and one control. In all instances, Edenhope residence preceded disease onset. No one environmental agent was implicated in all cases.

CONCLUSION

A spatiotemporal cluster of systemic scleroderma was confirmed and validated. It occurred with a tenfold increased cumulative incidence to that expected and also extended beyond the initially defined 50 km radius of Edenhope. The cases identified were not related. Although no one specific environmental agent was identified, the spatiotemporal clustering would be compatible with an agent occurring at relatively high frequency, but with low disease conversion rates, such as silica inhalation (assuming sufficiently small particle size) or reaction to an infective agent.

Secondary screening for osteoporosis in patients admitted with minimal-trauma fracture to a major teaching hospital

AIMS

The aim of the present study was to determine: (i) the prevalence of the investigation and treatment of osteoporosis in patients admitted to hospital with a minimal-trauma fracture, (ii) the prevalence of osteoporosis using bone mineral density assessment by dual X-ray absorptiometry (DEXA) in such patients and (iii) a clinical pathway for the management of osteoporosis in such patients.

METHODS

A cross-sectional study was undertaken involving all patients admitted with a fracture to Westmead Hospital, Sydney, Australia, between January 1999 and June 2000 (n = 327). Of these, 264 were excluded because of: (i) the fracture following significant trauma (n = 83), (ii) unavailability of medical records for review (n = 38), (iii) nursing home status (n = 37), (iv) previous malignancy (n = 18), (v) deceased (n = 11), (vi) recent osteoporosis screening and/or treatment (n = 18), (vii) refusal to participate (n = 37), (viii) uncontactable (n = 16) and (ix) inadequate English (n = 6). The remaining 63 patients underwent DEXA assessment and the following laboratory investigations: (i) liver function tests, (ii) urea, (iii) electrolytes, (iv) calcium, (v) phosphate, (vi) full blood count, (v) 25-hydroxyvitamin D level and (vi) thyroid-function tests. In men, levels of serum free testosterone, luteinizing hormone, follicle-stimulating hormone and prolactin were also obtained.

RESULTS

Of the 63 study participants, 87% of the 47 women were either osteoporotic (T <-2.5) or osteopenic (-2.5 <T <-1) at a mean of 12.7 +/- 5.4 months post-fracture. Of the 16 men screened, 75% had a T-score < or =-1. Forty-four per cent of the study sample had a low 25-hydroxyvitamin D level, 6% were biochemically hyperthyroid and 40% of the men had a low serum free testosterone. Only 16% had an effective anti-osteoporotic medication added following the fracture.

CONCLUSIONS

Secondary screening and treatment of osteoporosis in patients following minimal-trauma fracture are low. The implementation of a clinical pathway for osteoporosis management in these patients may be useful.

Relationship of tumour necrosis factor alpha gene polymorphisms and neuropsychiatric lupus

Systemic lupus erythematosus (SLE) is a multisystem disorder which appears to be influenced by genetic make-up. In this study we determine allele frequency and genotype distribution of TNFalpha polymorphisms in two populations of SLE patients (with and without neuropsychiatric manifestations) in order to determine whether the rare allele (TNF2) confers susceptibility for neuropsychiatric disease in SLE. Patients with SLE were retrospectively reviewed to determine presence (n = 17) or absence (n = 47) of documented neuropsychiatric manifestations attributable to SLE. The DNA from these patients was extracted from peripheral blood mononuclear cells, and PCR amplification, NcoI enzyme digestion and 10% polyacrylamide gel electrophoresis were performed to define the different TNFalpha alleles. Two alleles were demonstrated, TNF1 (wild-type) and TNF2 (rare type), with three possible genotypes, TNF1,1, TNF1,2 and TNF2,2. A frequency of 24% was found for the TNF2 patients with neuropsychiatric involvement and was not statistically different to a frequency of 28% found in SLE patients without neuropsychiatric manifestations. The TNF-2 allele does not confer susceptibility for neuropsychiatric manifestations in SLE patients.

CCR5 genotyping in an Australian and New Zealand type 1 diabetes cohort

Infiltration of pancreatic tissue by autoreactive T-cells involves secretion of multiple cytokines and chemokine receptor expression. Genetically determined variation in cell surface expression of the chemokine receptor CCR5 may result in differences in inflammatory cell migration in response to relevant chemokines. Adolescents with type 1 diabetes (T1D) from Australia and New Zealand were genotyped for CCR5-delta32 (n = 626). The allele frequency was compared with that of 253 non-diabetic Australian adolescents and with that of 92 adults with systemic lupus erythematosus. A reduced allele frequency was seen in T1D compared with controls (0.092 vs. 0.123, p = 0.05). This difference was not seen for the cohort of patients with SLE (freq = 0.114). A reduction in the number of CCR5-delta32/delta32 homozygotes, who lack CCR5, in the T1D cohort was also seen and while not statistically significant (2 observed compared to 5.25 expected; p = 0.12) is interesting. These results suggest a partial protection from T1D for CCR5-delta32 homozygous individuals is possible and that CCR5 has a potential role in the pathogenesis of T1D.

Glucosamine. A nutraceutical in osteoarthritis

BACKGROUND

Glucosamine is an amine-sugar that has been marketed as a natural product for the treatment of osteoarthritis. It has been popularized in the complementary section of pharmacies as a safe over-the-counter treatment for osteoarthritic pain.

OBJECTIVE

We review the literature on the efficacy and safety of glucosamine in osteoarthritis.

DISCUSSION

Recent research suggests that it may not only provide symptomatic pain relief, but may have a role in chondroprotection.

Failure to detect Bartonella henselae infection in synovial fluid from sufferers of chronic arthritis

Bartonella henselae causes granulomatous and indolent infection in the immune competent human, and angioproliferation in the context of persistent infection and impaired immunity. This bacterium is found in up to 40% of household cats, from which humans acquire it by either a cat scratch or a bite (hence the name, cat-scratch disease). Approximately 5% of Australian and US blood donors have serological evidence of past infection, but most associated illnesses are mild or subclinical. A number of lines of evidence prompted us to consider a relationship between rheumatoid arthritis (RA) and Bartonella infection. These include epidemiological associations with household pet exposure; apparent responsiveness of some RA cases to tetracycline therapy; the granulomatous and angioproliferative nature of Bartonella lesions; the insidiousness and high seroprevalence of this infection in the community; and even reported Bartonella infection mimicking juvenile RA. In a small group of patients with chronic arthritides, we found no direct evidence of humoral antibodies to, nor of persistent infection with, Bartonella henselae in synovial fluid. While larger and more invasive studies are likely to provide more confident exclusions of this hypothesis, this suggests that persistent Bartonella infection is unlikely to play a major role in RA.

Scleroderma in association with the use of docetaxel (taxotere) for breast cancer

The taxanes, paclitaxel (Taxol) and docetaxal (Taxotere), are a new class of anti-microtubule agents which have shown cytotoxic activity in a number of solid tumours. Phase I and II trials confirm that docetaxal is highly active in the treatment of metastatic breast cancer. Reported toxicities of docetaxel include, dose limiting neutropenia, alopecia, skin reactions and fluid retention. Here we report the first case of rapid onset, diffuse scleroderma-like illness, which occurred in a 59-year-old female receiving treatment with docetaxel for locally invasive and advanced metastatic breast cancer.

Investigation of the -1377 polymorphism on the Apo-1/Fas promoter in systemic lupus erythematosus patients using allele-specific amplification

Apoptosis mediated by the Apo-1/Fas and Fas ligand pathways has been implicated in many disorders, including autoimmunity and tumorigenesis. The recent identification of two polymorphisms on the 5' flanking region of the human Apo-1/Fas gene has provided useful markers for investigation of the genetic contribution of the Apo-1/Fas gene in these diseases. The Mval polymorphism at the -670 nucleotide position is frequent in the normal population, with 51% heterozygosity. The other polymorphism, a result of single nucleotide G-->A substitution at the -1377 position, does not create or delete any restriction enzyme digestion sites. In this paper, we describe a simple and rapid method for detecting the -1377 polymorphism by using allele-specific amplification (ASA). Using the ASA method, the -1377 polymorphism in a normal Caucasian population was characterised. Frequencies of 0.13 and 0.87 for allele A and G, respectively, were observed and the homozygosity of the mutant allele (A) was found in only 2% of the population. We subsequently examined the -1377 polymorphism in sporadic systemic lupus erythematosus (SLE) patients (n = 86). The results showed that both genotype distribution and allele frequencies in SLE patients were similar to that in controls, suggesting that the -1377 promoter polymorphism is unlikely to be associated with SLE susceptibility. The description of this rapid detection method and characterisation of the -1377 polymorphism are useful means for future genetic studies in diseases in which the Fas-mediated apoptosis may be involved.

Evaluation of the apo-1/Fas promoter mva I polymorphism in multiple sclerosis

The pathogenesis of multiple sclerosis is under strong genetic control involving several or more genes each of modest effect. Whilst the mechanisms underlying the pathogenesis of MS remain unknown, it has been hypothesised that either decreased apoptosis of autoreactive T cells in the CNS, or increased apoptosis of oligodendrocytes may play an important role. The Apo-1/Fas antigen (CD95), the gene for which is located in a chromosomal region showing linkage in MS genome screens, is a critical inducer of apoptosis and studies have shown aberrant expression of this molecule in MS, correlating with a decrease in T cell apoptosis or increase in CNS tissue damage. This study investigated an Mva I polymorphism in the Apo-1/Fas promoter region in a group of 124 Australian patients with relapsing-remitting MS and in 183 normal controls. Whilst there were increases in the Mva I*2 allele in MS individuals overall (59% vs 52%, P not corrected=0.08), and in HLA-DRB1*1501 negative MS patients (62% vs 55%), these were not significantly different from controls. Interactions were investigated between the Mva I alleles and T cell receptor beta chain variable region (TCRBV) germline polymorphisms, with a trend in MS individuals towards a decrease of the Mva I*1 allele when combined with the TCRBV3S1*2 allele (Relative Risk=0.25, P=0.067), and with the TCRBV8S1*1 allele (Relative Risk=0.44, P=0.12). Overall, the findings of this study indicate a possible effect of the Apo-1/Fas promoter Mva I polymorphism in MS susceptibility, which needs to be confirmed in further studies. Multiple Sclerosis (2000) 6 14 - 18

A Fas promoter polymorphism at position -670 in the enhancer region does not confer susceptibility to Felty's and large granular lymphocyte syndromes

OBJECTIVE

We examined whether there are associations between a polymorphism in the Fas promoter, recently found to be associated with rheumatoid arthritis (RA), and Felty's syndrome or large granular lymphocyte (LGL) leukaemia.

METHODS

Thirty-five patients with Felty's were studied, along with 18 patients with LGL syndrome and arthritis, 17 patients with LGL syndrome but no arthritis, and 128 controls. The polymorphism was typed by polymerase chain reaction followed by digestion with the restriction enzyme MvaI.

RESULTS

No significant difference was found in genotype or allele frequencies between the groups.

CONCLUSION

This promoter polymorphism is not a significant risk factor responsible for the LGL expansions seen in Felty's and LGL syndromes. Abnormal, constitutive expression of Fas ligand may be more relevant to the aetiology of these diseases.

Evaluation of a new Apo-1/Fas promoter polymorphism in rheumatoid arthritis and systemic lupus erythematosus patients

OBJECTIVE

We looked for an association between the MvaI polymorphism, a recently reported polymorphism on the promoter of the Apo-1/Fas gene, and rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) patients.

METHODS

Two cohorts of Caucasian RA patients (total number = 185) and one cohort of SLE patients (n = 103) were studied. The MvaI polymorphism was typed by polymerase chain reaction and followed by MvaI digestion and gel electrophoresis.

RESULTS

A skewed distribution of MvaI genotypes was found in the first cohort of RA patients (n = 103) compared to the controls, as a result of increased MvaI*2 and decreased MvaI*1 homozygosity. This skewed distribution of genotypes was also observed in RA patients with either early onset of disease or with systemic involvement or progressive disease (assessed by the presence of erosions). The frequency of the MvaI*2 allele was significantly increased in female patients (P = 0.035), patients with extra-articular involvement (P = 0.04) and patients with early onset (P < 0.01), compared to the normals. To confirm these findings, the MvaI polymorphism was also examined in a second cohort of RA patients (n = 82). The results in this cohort did not replicate the associations shown in the first cohort of RA patients. Part of this inconsistency could be attributed to different populations and different parameters collected and analysed. In SLE patients, frequencies of MvaI alleles were not statistically different to the controls. However, MvaI*2 homozygosity was significantly higher in SLE patients with photosensitivity (P = 0.03) or oral ulcers (P = 0.01) than in SLE patients without these features.

CONCLUSION

The role of the Apo-1/Fas gene promoter MvaI polymorphism in RA and SLE is unclear and further substantiation in larger patient samples is needed.

Familial risk estimation in systemic sclerosis

BACKGROUND

Familial systemic sclerosis has been rarely reported. Assumptions have therefore been made implying no familial disease aggregation. This study critically challenges the assumption using a methodical population-based epidemiological approach to quantify the prevalence and characteristics of familial systemic sclerosis.

METHODS

In this retrospective cohort study the systemic sclerosis prevalence in first degree family members was compared between 715 systemic sclerosis patients (710 families) and 371 randomly ascertained age and gender group-matched general practice controls (371 families). These data, obtained by telephone questionnaire (living patients) or medical records review (deceased patients and untraceable patients of unknown living status), were validated, where necessary, and expressed in terms of relative risk, absolute risk and population point prevalence.

RESULTS

Systemic sclerosis affecting first degree members was validated in ten of 710 families. Reporting of systemic disease in another four more distant family members, and the co-occurrence of systemic and localised disease in three families was also documented. Observed and expected disease subtype concordance was 80% (44-97%) and 68% respectively and the female predominance among familial cases was similar to that for non-familial disease. The risk of disease in a subsequent first degree relative was compared to the risk in an initial first degree family member. Its estimated magnitude was wide (11-158). However, use of population prevalence data to determine the expected number of systemic sclerosis patients in the negative cohorts' families suggests the higher estimate is more realistic. Despite the high magnitude, the absolute disease risk in first degree family members remained low--approximating 1%. The population prevalence of familial systemic sclerosis approximated 1.4/million.

CONCLUSIONS

This study substantially increases the otherwise small list of documented instances of familial systemic sclerosis. More importantly, it quantifies the risk for the first time, ranking it as the disease's most powerful determinant identified to date.

The interchain disulfide linkage of T-cell antigen receptor-alpha and -beta chains is a prerequisite for T-cell activation

Complementary DNAs encoding the T-cell antigen receptor (TCR)-alpha and mutant TCR-beta chains, lacking the interchain disulfide bond-related cysteine, were introduced into a TCR-alpha and -beta protein-deficient T-cell line. TCR-alpha and the mutant TCR-beta chains assembled with the CD3-epsilon, -gamma, -delta, and -zeta subunits and were efficiently transported to the cell surface; however, the hybrid TCR molecules exhibited a diminished response to T-cell activation by major histocompatibility complex-bound antigen, superantigen, and TCR cross-linking. These results suggest that the interchain disulfide bond between the TCR clonotypic chains is not required for TCR assembly and cell surface expression, but it plays an important role in maintaining the functional integrity of the TCR complex.

X-chromosome inactivation in monozygotic twins with systemic lupus erythematosus

The hypothesis that a low concordance rate in monozygotic (MZ) twins with systemic lupus erythematosus (SLE) may be accounted for by differences in X-chromosome inactivation was examined. Five MZ twin pairs, four discordant and one concordant, were recruited, zygosity confirmed by DNA fingerprinting, and their pattern of X-chromosome inactivation in DNA samples prepared from peripheral blood and buccal cells were examined. X-chromosome inactivation was assessed by the methylation status of the CpG region near trinucleotide repeats in exon 1 of the androgen receptor gene on X-chromosome after digestion with the methylation-sensitive enzyme HpaII or HhaI and PCR amplification. X-chromosome inactivation patterns were found to be the same between affected and non-affected twins in all four discordant twin pairs, with random patterns in two pairs and skewed patterns in the others. The concordant twins demonstrated the same random patterns. X-chromosome inactivation was also examined from buccal smear DNA and shown to have the same pattern as that noted from peripheral blood DNA in one informative twin pair. Differences in X-chromosome inactivation patterns were not observed in these five MZ twin pairs. The results could not support the hypothesis that differences in X-chromosome inactivation is the mechanism accounting for the low concordance rate noted in MZ twins with SLE.

Identification and characterization of polymorphisms in the promoter region of the human Apo-1/Fas (CD95) gene

Apo-1/Fas (CD95) is a transmembrane protein expressed on the cell surface that is involved in apoptosis and plays an important role in the function and regulation of the immune system. Aberrant expression of the Apo-1/Fas gene product has been reported in a number of immune-related disorders, such as autoimmune lymphoproliferative syndrome and systemic lupus erythematosus in humans. Mutations in the coding sequence of the Apo-1/Fas gene have been reported in the former condition, whereas no abnormalities of the gene have been found to account for the increased gene expression noted in SLE. We screened the whole 5' flanking region of the Apo-1/Fas gene encompassing over 2000 bp for mutation(s)/polymorphism(s) using multiplex PCR, single-strand conformation polymorphism (SSCP) analysis and sequencing techniques, and identified two polymorphisms in this region. The first polymorphism is a CG-->CA substitution at -1377 nucleotide position within the silencer region, which neither creates or deletes any restriction enzyme sites but alters the transcription factor SP-1 binding site. This polymorphism is noted in 20% of normal Caucasians. The second polymorphism is an GA-->GG substitution at -670 nucleotide position in the enhancer region that creates a MvaI restriction fragment length polymorphism (RFLP) and abolishes the binding site of nuclear transcription element GAS. The MvaI RFLP is polymorphic with heterozygosity of 52% and the frequency of G and A alleles are 0.49 and 0.51, respectively. The identification and characterisation of these two new polymorphisms, particularly the MvaI RFLP marker, provides new genetic markers and may prove useful for further studies on the regulation of apoptosis mediated by the Apo-1/Fas gene on human chromosome 10q23.

Family and twin studies in systemic lupus erythematosus

We have estimated how much of the total genetic predisposition to SLE may be attributable to genes outside the HLA region by comparing figures for concordance of SLE in monozygotic twins with those for concordance in HLA identical siblings in Australia. None of six dizygotic co-twins of white Australian SLE probands was concordant for SLE. One of four (25%) monozygotic co-twins of white Australian SLE probands was concordant for SLE which when added to previously published figures for Caucasoid populations gives an overall concordance rate for SLE in monozygotic twins of 25%. None of 18 HLA identical, same sex siblings of SLE probands, had definite SLE by the study criteria (i.e. less than 6%). The comparison of these figures shows that most of the genetic predisposition to SLE is attributable to genes outside the HLA region.

T-cell antigen receptor transmembrane peptides modulate T-cell function and T cell-mediated disease

This study describes a novel method of inhibiting T-cell function by the use of peptides rationally designed from the T-cell antigen receptor (TCR) alpha-chain transmembrane sequence involved with TCR receptor assembly. The most effective peptide (core peptide, CP) modulating in vitro and in vivo T-cell function contained nine amino acids two of which, lysine and arginine, were hydrophilic and separated by four hydrophobic amino acids. CP without chemical modification or conjugation was able to enter non-T and T cells. Conjugation of CP at the carboxyl terminus with palmitic acid resulted in a greater inhibition of T-cell interleukin-2 (IL-2) production in vitro than peptide alone. When examined for effects in vivo, CP reduced clinical signs of inflammation in three T cell-mediated disease models including adjuvant-induced arthritis, experimental allergic neuritis, and cyclophosphamide-induced diabetes in NOD/Lt(F) mice. This peptide or its analogues has potential as a therapeutic agent in human inflammatory and autoimmune disorders.

Lack of linkage between anti-nuclear antibody or clinical features of systemic lupus erythematosus (SLE) and TCR-A/Vbeta loci in families of subjects with SLE

The role of the TCR-A and TCR-Vbeta genes in the genetic predisposition to SLE expression and anti-nuclear antibody (ANA) production were examined by linkage analysis in eighteen multiplex and forty-three simplex SLE families. All subjects were Caucasian. A significantly increased prevalence of positive ANAs in first-degree relatives of SLE patients from multiplex families was noticed compared to that of simplex families. Linkage between TCR-A/Vbeta genes and SLE expression and ANA production were analysed by affected sib-pair method. Results showed that the haplotypes identical by descent sharing TCR-A and TCR-Vbeta genes in the affected sib-pairs was not different from that expected (P = 0.93 and P = 0.74, respectively). There was no linkage between ANA positivity and TCR-A and TCR-Vbeta genes in ANA positive sib-pairs from both multiplex and simplex families. This study suggests that germline TCR-A and TCR-Vbeta gene loci confer no susceptibility to ANA and SLE expression.

Structural mutations in the constant region of the T-cell antigen receptor (TCR)beta chain and their effect on TCR alpha and beta chain interaction

The region responsible for T-cell receptor (TCR)alpha and beta chain assembly has previously been shown to reside in their extracellular domains. In an attempt to delineate further the structural requirements for TCR alpha and beta chain assembly, chimeric TCR beta chains with increasing length of constant (C) region and mutant TCR beta chains with C-domain point mutations were constructed. Their ability to assemble with wild-type TCR alpha chain was evaluated in non-T (COS cells) or T cells. The results reveal that the C beta domain is the binding region to TCR alpha chain, whereas the intact variable (V), diversity (D) and joining (J) regions with a short C-domain of beta chain are not sufficient for the TCR alpha and beta chain assembly. The unique interchain disulphide bond between TCR alpha and beta chains is not required for the TCR alpha beta heterodimer formation.