HW, Bridges Jr. SL, Pisetsky DS, Ward R, Kastner DL, Wilder RL, Pincus T, Callahan LF, Flemming D, Wener MH, Gregersen PK. A genomewide screen in multiplex rheumatoid arthritis families suggests genetic overlap with other autoimmune diseases

Rheumatoid arthritis (RA) is an autoimmune/inflammatory disorder with a complex genetic component. We report the first major genomewide screen of multiplex families with RA gathered in the United States. The North American Rheumatoid Arthritis Consortium, using well-defined clinical criteria, has collected 257 families containing 301 affected sibling pairs with RA. A genome screen for allele sharing was performed, using 379 microsatellite markers. A nonparametric analysis using SIBPAL confirmed linkage of the HLA locus to RA (P < .00005), with lambdaHLA = 1.79. However, the analysis also revealed a number of non-HLA loci on chromosomes 1 (D1S235), 4 (D4S1647), 12 (D12S373), 16 (D16S403), and 17 (D17S1301), with evidence for linkage at a significance level of P<.005. Analysis of X-linked markers using the MLOD method from ASPEX also suggests linkage to the telomeric marker DXS6807. Stratifying the families into white or seropositive subgroups revealed some additional markers that showed improvement in significance over the full data set. Several of the regions that showed evidence for nominal significance (P < .05) in our data set had previously been implicated in RA (D16S516 and D17S1301) or in other diseases of an autoimmune nature, including systemic lupus erythematosus (D1S235), inflammatory bowel disease (D4S1647, D5S1462, and D16S516), multiple sclerosis (D12S1052), and ankylosing spondylitis (D16S516). Therefore, genes in the HLA complex play a major role in RA susceptibility, but several other regions also contribute significantly to overall genetic risk.

Laminin-5 promotes neurite outgrowth from central and peripheral chick embryonic neurons

Laminin-5 (Ln-5) is an essential component of epithelial basal laminae that is also expressed in the developing nervous system. Here we use a convenient, simple and reproducible in vitro fluorescent assay to assess the neurite outgrowth promoting activity of purified Ln-5. Embryonic chick neurons from dorsal root ganglia, ciliary ganglia, and (to a lesser extent) retina extended neurites on Ln-5, but the neurite outgrowth promoting activity was not as great as that of Ln-1 or Ln-2. Neurons from diencephalon, telencephalon, and spinal cord did not respond to Ln-5.

Adhesive events in retinal development and function: the role of integrin receptors

Cells in the developing retina contact a vast array of molecular cues in their microenvironment that are thought to guide their development. Many of these cues are embedded in the surface of neighboring cells or deposited within the extracellular matrix (ECM). Evidence has accumulated that cell-cell and cell-ECM interactions are essential in many phases of neural development, including neuroblast migration, determination of cell fate, axon outgrowth and synapse formation. In this chapter, we examine the developmental and functional roles fulfilled by integrins, a family of receptors for ECM molecules and cell adhesion molecules (CAMs). We have approached this problem by addressing a series of three questions: (1) which integrins are expressed in developing retina? (2) when and where are they expressed? and, (3) what functions do they carry out? Integrins have previously been implicated in axon extension, but new evidence suggests that they are also involved in earlier developmental events in preaxonal neuroblasts. High levels of expression of at least eight integrin subunits have been documented in these young retinal cells, and integrins containing the beta 1 subunit have been implicated in migration of adolescent retinal ganglion cells. Integrin expression persists through adulthood, both in the retina and in the neighboring layer of the retinal pigment epithelium (RPE). The integrin alpha v beta 5 has been shown to reside on the apical surface of the RPE and has been implicated in the phagocytosis of shed photoreceptor outer segments.

Modelling the major histocompatibility complex susceptibility to RA using the MASC method

To explain the association between HLA-DRB1 gene and rheumatoid arthritis (RA), two main hypotheses have been proposed. The first, the shared epitope hypothesis, assumes a direct role of DRB1 in RA susceptibility. The second hypothesis assumes a recessive disease susceptibility gene in linkage disequilibrium with DRB1. To investigate these two hypotheses, we analysed data on the HLA-DRB1 and TNF-LT loci in 49 affected sib-pairs. We used the Marker Association Segregation Chi-square (MASC) method in which the genotype distribution of markers among index cases and the haplotype sharing in affected sib-pairs are jointly taken into account. With DRB1 data alone, both hypotheses were shown to fit but with analysis of TNF data, both hypotheses were strongly rejected. Thus the TNF data provided additional information for a better understanding of genetic susceptibility to RA than was previously possible using only HLA-DR data. A theoretical standpoint is addressed here on the advisability of using different linked markers in a candidate region for modelling the contribution of this region in disease susceptibility.

Imaging and mapping heparin-binding sites on single fibronectin molecules with atomic force microscopy

Fibronectin is composed of multiple homologous repeats and contains many functional domains. Two major heparin-binding domains have previously been identified: the Hep I site near the amino terminus and the Hep II site near the carboxyl terminus. The Hep II site has been considered the high-affinity heparin-binding site based on studies of fibronectin fragments. However, few studies have been carried out on heparin binding by intact fibronectin. We imaged single fibronectin molecules as well as heparin-coated gold particles bound to whole dimeric plasma fibronectin molecules with tapping mode atomic force microscopy. We observed heparin-gold particles preferentially bound at two locations that correspond to the Hep I and Hep II sites. Quantitative analysis of images of individual fibronectin-heparin-gold complexes showed that almost twice as many heparin-gold particles bound to the N-terminal Hep I site compared to the Hep II site. In contrast to previous findings with fibronectin fragments, these results suggest that the Hep I site has a binding affinity higher than or comparable to the Hep II site in the intact fibronectin molecule.

Comparison of sulfasalazine and placebo for the treatment of axial and peripheral articular manifestations of the seronegative spondylarthropathies: a Department of Veterans Affairs cooperative study

OBJECTIVE

To determine if the peripheral articular manifestations of the seronegative spondylarthropathies (SNSA) respond differently than the axial manifestations to treatment with sulfasalazine (SSZ).

METHODS

This is a reanalysis of a previously reported series of randomized, double-blind, placebo-controlled, multicenter trials comparing the effects of SSZ, 2,000 mg/day, and placebo on the axial and peripheral articular manifestations of ankylosing spondylitis (AS), psoriatic arthritis (PsA), and reactive arthritis (ReA; Reiter's syndrome). Patients were classified as treatment responders on the basis of meeting predefined improvement criteria in 4 outcome measures: namely, patient and physician global assessments in all patients, morning stiffness and back pain in patients with axial manifestations, and joint pain/tenderness scores and joint swelling scores in patients with peripheral articular manifestations.

RESULTS

Six hundred nineteen SNSA patients (264 AS, 221 PsA, and 134 ReA) were studied. One hundred eighty-seven of these patients had only axial manifestations of their disease, while 432 patients had peripheral articular manifestations. Of the patients with axial disease, 40.2% of the SSZ group and 43.3% of the placebo group met the predefined response criteria (P = 0.67). Of the peripheral articular group, 59.0% of the SSZ-treated patients and 42.7% of the placebo-treated patients showed a response (P = 0.0007).

CONCLUSION

In a large group of affected individuals, the response of SNSA patients to SSZ appears to be related to the articular manifestations of their disease. These data demonstrate that the axial and peripheral articular manifestations of SNSA respond differently to treatment with SSZ. In SNSA patients with persistently active peripheral arthritis, SSZ is safe, well tolerated, and effective.

Comparison of sulfasalazine and placebo for the treatment of axial and peripheral articular manifestations of the seronegative spondylarthropathies: a Department of Veterans Affairs cooperative study

OBJECTIVE

To determine if the peripheral articular manifestations of the seronegative spondylarthropathies (SNSA) respond differently than the axial manifestations to treatment with sulfasalazine (SSZ).

METHODS

This is a reanalysis of a previously reported series of randomized, double-blind, placebo-controlled, multicenter trials comparing the effects of SSZ, 2,000 mg/day, and placebo on the axial and peripheral articular manifestations of ankylosing spondylitis (AS), psoriatic arthritis (PsA), and reactive arthritis (ReA; Reiter's syndrome). Patients were classified as treatment responders on the basis of meeting predefined improvement criteria in 4 outcome measures: namely, patient and physician global assessments in all patients, morning stiffness and back pain in patients with axial manifestations, and joint pain/tenderness scores and joint swelling scores in patients with peripheral articular manifestations.

RESULTS

Six hundred nineteen SNSA patients (264 AS, 221 PsA, and 134 ReA) were studied. One hundred eighty-seven of these patients had only axial manifestations of their disease, while 432 patients had peripheral articular manifestations. Of the patients with axial disease, 40.2% of the SSZ group and 43.3% of the placebo group met the predefined response criteria (P = 0.67). Of the peripheral articular group, 59.0% of the SSZ-treated patients and 42.7% of the placebo-treated patients showed a response (P = 0.0007).

CONCLUSION

In a large group of affected individuals, the response of SNSA patients to SSZ appears to be related to the articular manifestations of their disease. These data demonstrate that the axial and peripheral articular manifestations of SNSA respond differently to treatment with SSZ. In SNSA patients with persistently active peripheral arthritis, SSZ is safe, well tolerated, and effective.

Global statistical tests for comparing multiple outcomes in rheumatoid arthritis trials. MIRA Trial Group

OBJECTIVE

To evaluate global statistical tests (GSTs) of treatment effectiveness for rheumatoid arthritis (RA) trials measuring multiple outcomes.

METHODS

Using outcome measures from American College of Rheumatology (ACR) core set variables available in 3 RA trials, GSTs were calculated using the O'Brien ranking procedure and a procedure for binary data. GSTs take correlations among outcomes into account. Power calculations using 1 trial data set provide comparisons of GSTs and ACR criteria for improvement.

RESULTS

Spearman correlations among outcomes ranged from 0.21 to 0.73. Erythrocyte sedimentation rate had the lowest correlation with other outcomes in all 3 trials. Within a trial, joint swelling and joint tenderness or patient and physician assessment had the highest correlations, depending on the trial. Results were consistent with results using the ACR criteria, although the GST was more powerful.

CONCLUSION

GSTs are a useful tool for comparing treatment effects across multiple clinically meaningful outcome measures. The GST allows easy inclusion of validated, reliable new measures that are not a part of ACR criteria, such as quality of life, and can be computed with or without selecting a cutoff point defining patient improvement. GSTs should be considered for rheumatic disease treatment trials.

Imaging real-time proteolysis of single collagen I molecules with an atomic force microscope

The dynamic process of synthesis and degradation of extracellular matrix molecules, including various collagens, is important in normal physiological functions and pathological conditions. Existing models of collagen enzymatic degradation reactions are derived from bulk biochemical assays. In this study, we have imaged in real-time individual collagen I molecules and their proteolysis by Clostridium histolyticum collagenases in phosphate-buffered saline (PBS) with atomic force microscopy (AFM). We have also imaged the likely binding and unbinding of collagenase molecules to single triple-helical collagen I molecules and subsequent proteolysis of subsets of the collagen molecules. The proteolysis of collagen molecules was inhibited by reduced calcium and acidification. Results from AFM study of collagen proteolysis are consistent with SDS-PAGE biochemical assays. The real-time proteolysis of single collagen I molecules followed simple Michaelis-Menton kinetics previously derived from bulk biochemical assays. This is the first report of imaging real-time proteolysis of single macromolecules and its inhibition on a molecular scale. A strong correspondence between the kinetics of proteolysis of single collagen molecules and the kinetics of proteolysis derived from bulk biochemical assays will have a wide applicability in examining real-time enzymatic reactions and their regulation at single molecule structural level. Such real-time study of single molecule proteolysis could provide a better understanding of the interactions between proteases and target proteins as well as proteases and protease inhibitors.

Baseline relationships between psoriasis and psoriatic arthritis: analysis of 221 patients with active psoriatic arthritis. Department of Veterans Affairs Cooperative Study Group on Seronegative Spondyloarthropathies

OBJECTIVE

To determine differences in disease onset, extent, and manifestations of psoriasis among patients with active, inflammatory psoriatic arthritis (PsA), and to examine relationships that may exist between psoriasis and PsA.

METHODS

Baseline demographic, clinical, and laboratory data were analyzed from 221 patients enrolled in a multicenter cooperative study, and relationships between measures of psoriasis and PsA were determined.

RESULTS

Mean percentage of body surface area (BSA) affected by psoriasis was modest (12+/-17), and mean severity of erythema, induration, and scaling was moderate (4.9+/-2.1 on a 0-9 scale). Spanish Americans tended to have a higher mean percentage of BSA (18.5%) than Caucasians (11%; p = 0.067), as well as higher target lesion severity (5.55 vs. 4.84; p = 0.077). Patients with psoriatic nail disease (180/221, 81%) had significantly greater number of involved distal interphalangeal (DIP) joints (p = 0.004). There were no other significant associations of skin pattern or regional involvement with PsA.

CONCLUSION

Patients with active PsA have generally mild skin disease, and baseline relationships between psoriasis and PsA tend to be weak except for nail involvement and DIP joint activity.

Early undifferentiated connective tissue disease (CTD). VI. An inception cohort after 10 years: disease remissions and changes in diagnoses in well established and undifferentiated CTD

OBJECTIVE

(1) To review the diagnoses after 10 years in patients who were identified within 12 months of the onset of well established and undifferentiated connective tissue diseases (CTD). (2) To examine the death rates and disease remissions in these patients.

METHODS

This inception cohort of 410 patients had less than one year of signs and/or symptoms of CTD. Diagnoses of rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), systemic sclerosis (SSc), and poly/dermatomyositis (PM/DM) were made in 197 patients using accepted diagnostic and classification criteria. Diagnoses of undifferentiated CTD were made in 213 patients. These latter patients were placed in 3 categories: isolated Raynaud's phenomenon (RP), unexplained polyarthritis (UPA), and undifferentiated CTD (UCTD), defined as meeting at least 3 of 11 specific manifestations of CTD. The diagnoses and remissions in all patients after 10 years were determined.

RESULTS

Patients with well established CTD tended to remain with the original diagnosis. The 10 year survival was at least 87% in all diagnostic categories, with the exception of SSc, in which it was 56%. The progression of UPA to RA occurred infrequently. The presence of antinuclear antibodies suggested that UPA may develop additional symptoms and/or a specific diagnosis, and RP in these patients increased the likelihood of progressing to UCTD or a specific well established CTD. Ten percent of patients with RP progressed to SSc. In patients with UCTD, joint pain/tenderness and swelling counts were associated with progression to other diagnoses including RA, while either serositis, malar rash, or discoid lupus suggested the eventual diagnosis of SLE.

CONCLUSION

The survival of patients with SSc was poor, with most dying early in the course of their disease. Remissions were seen in all groups of patients except SSc. The remissions were sometimes transient in SLE. Undifferentiated disease at initial examination within 12 months of onset usually remains undifferentiated.

The prevalence of sacroilitis in psoriatic arthritis: new perspectives from a large, multicenter cohort. A Department of Veterans Affairs Cooperative Study

OBJECTIVE

To determine the prevalence of radiographic evidence of sacroiliitis in a large population of patients with psoriatic arthritis.

PATIENTS AND DESIGN

Patients were recruited from 15 clinical centers. This was part of a large, multicenter study of patients with an established diagnosis of ankylosing spondylitis, psoriatic arthritis, or reactive arthritis. For this cohort, an established diagnosis of psoriatic arthritis was required, with cutaneous manifestations and involvement of at least three appendicular joints. At entry, patients were not selected for the presence of axial involvement. Radiographs - one anteroposterior view of the pelvis and one oblique view of each sacroiliac joint - were graded using the New York classification scale by a musculoskeletal radiologist masked to the specific diagnosis and clinical symptoms. Re-evaluation of 10% of the films 3 years later quantified intraobserver variability.

RESULTS

Two hundred and two patients with psoriatic arthritis were studied. Duration of the disease averaged 12 years; all patients had psoriasis and peripheral arthritis. The prevalence of radiographic evidence of sacroiliitis (grade 2 or higher) was 78%; 71% of these had grade 3 disease.

CONCLUSIONS

Previously reported prevalence of sacroiliitis in patients with psoriatic arthritis ranges from 30% to 50%. The prevalence of radiographic evidence of sacroiliitis in this large multicenter cohort of patients with appendicular psoriatic arthritis was substantially higher.

Radiographic diagnosis of sacroiliitis--are sacroiliac views really better?

OBJECTIVE

To determine whether detailed oblique radiographs of the sacroiliac (SI) joints provide significant diagnostic advantage to a single AP projection of the pelvis in establishing the presence and severity of sacroiliitis.

METHODS

Radiographs (both AP pelvis and detailed oblique projections) of 445 right SI joints and 442 left SI joints were obtained from patients with an established diagnosis of a seronegative spondyloarthropathy, and interpreted for severity. Data for the right and left SI joints were analyzed, comparing interpretations of severity based on AP pelvis projections with oblique views.

RESULTS

Analysis of these data showed an agreement rate between AP views and SI views of 89.7% for the right SI joint radiographs and 86.4% for the left SI joint. There was no instance in which a patient with "unequivocal abnormalities"of the SI joints on the AP pelvis was read as having "normal" SI views. Similarly, there were no cases in which "normal" SI joints on AP pelvis films were read as having unequivocal abnormalities on SI views.

CONCLUSION

In this group of patients with seronegative spondyloarthropathies, there was very close agreement between severity score of sacroiliitis from AP pelvis radiographs and SI joint views. We conclude that in most circumstances, the AP pelvis film will yield the diagnosis of sacroiliitis without the additional radiation exposure and expense related to specific SI joint radiographs.

Integrin alphavbeta5 participates in the binding of photoreceptor rod outer segments during phagocytosis by cultured human retinal pigment epithelium

PURPOSE

To examine the expression of integrin vitronectin receptors (integrins alphavbeta3 and alphavbeta5) in native human fetal retinal pigment epithelium (RPE) and cultured hunman fetal RPE and to examine the role of RPE VnRs in the phagocytosis of photoreceptor rod outer segments (ROS).

METHODS

Monoclonal antibodies against human integrin subunit alphav and heterodimers alphavbeta3 (LM609) and alphavbeta5 (P1F6) were used to label freshly isolated human fetal RPE explant and cultured human fetal RPE and to immunoprecipitate membrane proteins from cultured human RPE. Effects of antibodies and peptides that inhibit integrin vitronectin receptors on phagocytosis of ROS by RPE were determined using cultured human fetal RPE and fluorescein-labeled bovine outer segments.

RESULTS

Antibodies against integrin subunit alphav and against alphavbeta5 (P1F6) labeled the RPE apical membrane in both native tissue and cultured RPE, while anti-alphavbeta3 antibody (LM609) labeled less than 1% of cultured RPE and did not label native RPE. Antibodies against alphav and alphavbeta5 P1F6 also immunoprecipitated 2 protein bands corresponding to integrin subunits alphav and beta5 from a membrane extract of cultured human RPE. The peptide Gly-Arg-Gly-Asp-Ser-Pro (GRGDSP, 1 mM) inhibited the total ROS uptake (externally bound and ingested) by 48% (P < 0.001) and ingestion of ROS by 37% (P < 0.001). Antibody PIF6 (50 microg/ml) inhibited the total ROS uptake and the ingestion of ROS by 63% (P < 0.001) and 43% (P < 0.01), respectively.

CONCLUSIONS

The integrin alphavbeta5 vitronectin receptor is expressed on the apical membrane of human RPE and participates in the binding of photoreceptor ROS during phagocytosis by cultured human RPE.

Structures and dynamic motion of laminin-1 as observed by atomic force microscopy

Laminins are a family of multifunctional extracellular matrix glycoproteins that play important roles in the development and maintenance of tissue organization via their interactions with cells and other extracellular matrix proteins. To understand the structural basis of laminins' functions, we examined the motion of laminin-1 (Ln-1) in physiological buffers using atomic force microscopy. While many Ln-1 molecules assumed the expected cruciform structure, unexpected dynamic movements of the Ln-1 arms were observed in aqueous environments. These dynamic movements of the Ln-1 arms may contribute to the diversity of laminin functions.

Interactions of type IV collagen and its domains with human mesangial cells

Type IV collagen (COL-IV) interacts with a variety of cell types. We present evidence that human mesangial cells (HMC) bind directly to COL-IV, its major triple helical domain, and the main non-collagenous, NC1 domain. A synthetic peptide, HEP-III, and its triple helical counterpart (THP-III), previously reported to be a heparin-binding domain, also promoted approximately 15% adhesion of HMC. HMC bound to solid-phase-immobilized, intact COL-IV (approximately 75%), isolated NC1 domain (approximately 15%), and a pepsin-derived triple helical fragment,which lacks Hep-III (approximately 65%). We further examined inhibition of HMC adhesion to COL-IV and its domains by using anti-integrin antibodies. Blocking monoclonal antibodies against the alpha2 integrin resulted in 70% inhibition of adhesion to COL-IV and 80% inhibition to HEP-III. Moderate inhibition was observed on the NC1 and triple helical fragments. Anti-alpha1 antibodies inhibited the binding of HMC to COL-IV, the NC1, and triple helical domains, but not to peptide HEP-III. Anti-beta1 antibodies inhibited almost completely (>95%) the adhesion to COL-IV, the NC1, and triple helical fragments; inhibition on HEP-III was approximately 30%. Affinity chromatography studies with solid-phase HEP-III and mesangial cell lysate also demonstrated the presence of integrin alpha2 beta1 along with alpha3 beta1. We conclude that alpha2 beta1 and alpha1 beta1 integrins mediate HMC adhesion to COL-IV. Peptide HEP-III is a major, specific site for alpha2 integrin-mediated binding of mesangial cells to COL-IV. Both the alpha1 beta1 and alpha2 beta1 integrins interact with the NC1 and triple helical fragments of COL-IV. Therefore, we demonstrate that several sites for integrin-mediated interactions exist on several collagenous and non-collagenous domains of COL-IV.

Early undifferentiated connective tissue disease. V. An inception cohort 5 years later: disease remissions and changes in diagnoses in well established and undifferentiated connective tissue diseases

OBJECTIVE

To review the diagnoses after 5 years in patients who were identified within 12 months of the onset of well established and undifferentiated connective tissue diseases (CTD); to examine death rates and disease remissions in these patients.

METHODS

This inception cohort of 410 patients was identified in 10 academic rheumatology practices. They had less than one year of signs and/or symptoms of CTD. Diagnoses of specific well established CTD were made using accepted diagnostic and classification criteria. The diagnoses after 5 years were determined.

RESULTS

Patients with well established CTD tended to remain with the original diagnosis. The progression of unexplained polyarthritis to rheumatoid arthritis occurred infrequently. Ten percent of patients with isolated Raynaud's phenomenon progressed to systemic sclerosis (SSc). The 5 year survival was over 90% in all diagnostic categories, with the exception of SSc, in which it was 64%.

CONCLUSION

Patients with a well established CTD usually continued with the same diagnosis. Patients with undifferentiated CTD tended to remain undifferentiated or to remit.

Treatment of rheumatoid arthritis with oral type II collagen. Results of a multicenter, double-blind, placebo-controlled trial

OBJECTIVE

Oral administration of cartilage-derived type II collagen (CII) has been shown to ameliorate arthritis in animal models of joint inflammation, and preliminary studies have suggested that this novel therapy is clinically beneficial and safe in patients with rheumatoid arthritis (RA). The present study was undertaken to test the safety and efficacy of 4 different dosages of orally administered CII in patients with RA.

METHODS

Two hundred seventy-four patients with active RA were enrolled at 6 different sites and randomized to receive placebo or 1 of 4 dosages (20, 100, 500, or 2,500 microg/day) of oral CII for 24 weeks. Efficacy parameters were assessed monthly. Cumulative response rates (percentage of patients meeting the criteria for response at any time during the study) were analyzed utilizing 3 sets of composite criteria: the Paulus criteria, the American College of Rheumatology criteria for improvement in RA, and a requirement for > or = 30% reduction in both swollen and tender joint counts.

RESULTS

Eighty-three percent of patients completed 24 weeks of treatment. Numeric trends in favor of the 20 microg/day treatment group were seen with all 3 cumulative composite measures. However, a statistically significant increase (P = 0.035) in response rate for the 20 microg/day group versus placebo was detected using only the Paulus criteria. The presence of serum antibodies to CII at baseline was significantly associated with an increased likelihood of responding to treatment. No treatment-related adverse events were detected. The efficacy seen with the lowest dosage is consistent with the findings of animal studies and with known mechanisms of oral tolerance in which lower doses of orally administered autoantigens preferentially induce disease-suppressing regulatory cells.

CONCLUSION

Positive effects were observed with CII at the lowest dosage tested, and the presence of serum antibodies to CII at baseline may predict response to therapy. No side effects were associated with this novel therapeutic agent. Further controlled studies are required to assess the efficacy of this treatment approach.

A cross sectional assessment of health status instruments in patients with rheumatoid arthritis participating in a clinical trial. Minocycline in Rheumatoid Arthritis Trial Group

OBJECTIVE

To (1) validate the Short-Form Health Survey (SF-36) as a generic functional health status measure in patients with rheumatoid arthritis (RA); and (2) assess correlations between the SF-36 and other outcome measures used in the Minocycline in Rheumatoid Arthritis (MIRA) Trial.

METHODS

We conducted a cross sectional analysis of the final visit outcome measures from the 48 week, multicenter, placebo controlled, double blind MIRA trial. Multitrait scaling analyses assessed convergent and discriminant validity and internal consistency reliability of the SF-36 in the study patients. Responses to comparable items on the SF-36 and modified Health Assessment Questionnaire (M-HAQ) regarding physical functioning were compared and questions from both instruments were also compared to other RA outcome measures.

RESULTS

In patients with RA, the SF-36 had high internal consistency and reliability, high discriminant and high convergent validity. Moderate correlations were observed (r = -0.46 to -0.61, p < 0.01 in each case) for comparable items on the SF-36 and M-HAQ regarding dressing, walking, and bending. Joint tenderness score correlations with items on the M-HAQ and SF-36, and joint tenderness score correlations with the SF-36 scales were higher than for joint swelling scores. Physician and patient global assessments were most highly correlated (r = 0.58 and 0.66; p < 0.01, respectively) with the SF-36 bodily pain item.

CONCLUSION

The SF-36 is a valid instrument for this RA population. The SF-36 correlates with the M-HAQ and the physician and patient global assessments. The usefulness of the SF-36 in measuring change in RA clinical trials requires testing in longitudinal studies.

Safety and efficacy of hydroxychloroquine as maintenance therapy for rheumatoid arthritis after combination therapy with methotrexate and hydroxychloroquine

OBJECTIVE

To evaluate the ability of hydroxychloroquine sulfate (HCQ) to extend the response to combination therapy with HCQ and methotrexate (MTX) and the safety of longterm HCQ maintenance therapy in patients with active rheumatoid arthritis (RA).

METHODS

Two-part study consisting of an open label segment evaluating combination HCQ/MTX therapy followed by a double blind segment evaluating maintenance therapy for a total of 60 weeks. First, all patients were treated with HCQ 400 mg/day and MTX 7.5 to 15 mg/week for 24 weeks. Then, responders were randomized into 3 groups: (1) HCQ with MTX as needed for disease flare (n = 40), (2) HCQ 400 mg/day (n = 41), or (3) placebo with MTX as needed for disease flare (n = 40), each for 36 weeks.

RESULTS

Clinical disease and laboratory variables improved significantly during initial combination therapy with HCQ and MTX. After MTX withdrawal, HCQ-containing maintenance regimens delayed the onset of disease flare (p = 0.023). There were no unexpected adverse events at any time or between-group differences in the distribution of adverse events during the double blind segment.

CONCLUSION

Combination of HCQ and MTX appeared to be effective and well tolerated for 24 weeks. After withdrawal of MTX, HCQ extended the response seen with combination therapy and was well tolerated for 36 weeks. Initial therapy with HCQ and MTX, followed by maintenance HCQ, may be a useful alternative for the treatment of RA.

Radiographic results from the Minocycline in Rheumatoid Arthritis (MIRA) Trial

OBJECTIVE

To assess radiographically determined disease progression in patients in the Minocycline in Rheumatoid Arthritis (MIRA) Trial.

METHODS

A double blind, randomized, multicenter, 48 week trial of oral minocycline (200 mg/day) or placebo in 6 clinical centers in the United States. Patients include 219 adults with active RA previously receiving limited treatment with disease modifying drugs. Posteroanterior films of the hands from baseline and final visits, blinded for sequence, were read for erosions and joint space narrowing by trained observers. Outcomes included rate of disease progression (change/month) and percentage of patients with progression from baseline, newly involved joints, and newly erosive disease.

RESULTS

Using intent-to-treat analyses, progression rates for erosions (0.11 +/- 0.42 minocycline, 0.17 +/- 0.41 placebo; p = 0.47) and joint space narrowing (0.16 +/- 0.55 minocycline and 0.23 +/- 0.71 placebo; p = 0.14) were similar. (Power 43% to detect a 50% difference.) Newly erosive joints occurred more frequently in the placebo group (44 vs 32%; p = 0.08), not a statistically significant difference.

CONCLUSION

Radiographic measurement of disease progression using 4 measures failed to show a significant difference between minocycline and placebo treatment, although for all methods there was a trend toward treatment benefit, consistent with reported clinical results. A one year trial duration, high measurement variability, and slow rate of radiographic progression in this cohort may explain the low power to detect a treatment effect. The measurement that denoted "newly involved" joints was most sensitive in detecting change. In future trials longer term assessment (minimum 2 years) of radiographic changes and further comparison of measures of disease progression are warranted.

Meaningful improvement criteria sets in a rheumatoid arthritis clinical trial. MIRA Trial Group. Minocycline in Rheumatoid Arthritis

OBJECTIVE

To compare 3 sets of criteria for meaningful improvement in a rheumatoid arthritis (RA) clinical trial, and to evaluate the implications of these criteria sets for RA trial design.

METHODS

Data were obtained from the Minocycline in Rheumatoid Arthritis (MIRA) trial (primary outcome measures: 50% improvement in joint tenderness and 50% improvement in joint swelling, based on joint scores). These MIRA data were evaluated against 1) the Paulus criteria (20% improvement in 4 of 6 measures: joint tenderness scores, joint swelling scores, physician's and patient's global assessments, erythrocyte sedimentation rate [ESR], and morning stiffness); and 2) the American College of Rheumatology (ACR) criteria (20% improvement in joint tenderness and joint swelling counts, and in 3 of 5 other measures: physician's and patient's global assessments, ESR, modified Health Assessment Questionnaire, and patient's pain assessment). The ACR criteria were modified using 3 of 4 remaining measures, since baseline pain assessment data were not available.

RESULTS

Percentages of minocycline-treated patients versus placebo-treated patients showing meaningful improvement were as follows: by MIRA criteria, for joint tenderness, 56% versus 41% (P = 0.021), and for joint swelling, 54% versus 39% (P = 0.023); by Paulus criteria, 41% versus 28% (P = 0.040); and by ACR criteria, 44% versus 26% (P = 0.004). Both the modified ACR criteria and the Paulus criteria demonstrated a reduced placebo response rate. Compared with the MIRA criteria, the ACR criteria increased, and the Paulus criteria decreased, absolute between-group differences in improvement; however, both criteria sets increased relative percentages of patients showing improvement in the minocycline group versus the placebo group. Study design considerations indicated that application of the ACR criteria would reduce the required sample size.

CONCLUSION

Different placebo response rates and treatment group differences were found using the 3 RA improvement criteria sets. These findings support the use of the ACR criteria for defining improvement in RA clinical trials.

Comparison of sulfasalazine and placebo in the treatment of ankylosing spondylitis. A Department of Veterans Affairs Cooperative Study

OBJECTIVE

To determine whether sulfasalazine (SSZ) at a dosage of 2,000 mg/day is effective for the treatment of active ankylosing spondylitis (AS) that is not controlled with nonsteroidal antiinflammatory drug therapy.

METHODS

Two hundred sixty-four patients with AS were recruited from 15 clinics, randomized (double-blind) to SSZ or placebo treatment, and followed up for 36 weeks. Treatment response was based on morning stiffness, back pain, and physician and patient global assessments.

RESULTS

While longitudinal analysis revealed a trend favoring SSZ in the middle of treatment, no difference was seen at the end of treatment. Response rates were 38.2% for SSZ and 36.1% for placebo (P = 0.73). The Westergren erythrocyte sedimentation rate declined more with SSZ treatment than with placebo (P < 0.0001). AS patients with associated peripheral arthritis showed improvement that favored SSZ (P = 0.02). Adverse reactions were fewer than expected and were mainly due to nonspecific gastrointestinal complaints.

CONCLUSION

SSZ at a dosage of 2,000 mg/day does not seem to be more effective than placebo in the treatment of AS patients with chronic, longstanding disease. SSZ is well tolerated and may be more effective than placebo in the treatment of AS patients with peripheral joint involvement. This effect is more pronounced in treatment of the peripheral arthritis in this subgroup of AS patients.

Comparison of sulfasalazine and placebo in the treatment of psoriatic arthritis. A Department of Veterans Affairs Cooperative Study

OBJECTIVE

To determine whether sulfasalazine (SSZ) at a dosage of 2,000 mg/day is effective for the treatment of active psoriatic arthritis (PsA) resistant to nonsteroidal antiinflammatory drug therapy.

METHODS

Two hundred twenty-one patients with PsA were recruited from 15 clinics, randomized (double-blind) to SSZ or placebo treatment, and followed up for 36 weeks. Treatment response was based on joint pain/ tenderness and swelling scores and physician and patient global assessments.

RESULTS

Longitudinal analysis revealed a trend favoring SSZ treatment (P = 0.13). At the end of treatment, response rates were 57.8% for SSZ compared with 44.6% for placebo (P = 0.05). The Westergren erythrocyte sedimentation rate declined more in the PsA patients taking SSZ than in those taking placebo (P < 0.0001). Adverse reactions were fewer than expected and were mainly due to nonspecific gastrointestinal complaints, including dyspepsia, nausea, vomiting, and diarrhea.

CONCLUSION

SSZ at a dosage of 2,000 mg/day is well tolerated and may be more effective than placebo in the treatment of patients with PsA.

Comparison of sulfasalazine and placebo in the treatment of reactive arthritis (Reiter's syndrome). A Department of Veterans Affairs Cooperative Study

OBJECTIVE

To determine whether sulfasalazine (SSZ) at a dosage of 2,000 mg/day is effective in the treatment of reactive arthritis (ReA) that has been unresponsive to nonsteroidal antiinflammatory drug (NSAID) therapy.

METHODS

One hundred thirty-four patients with ReA who had failed to respond to NSAIDs were recruited from 19 clinics, randomized (double-blind) to receive either SSZ or placebo, and followed up for 36 weeks. The definition of treatment response was based on joint pain/tenderness and swelling scores and physician and patient global assessments.

RESULTS

Longitudinal analysis revealed improvement in the patients taking SSZ compared with those taking placebo, which appeared at 4 weeks and continued through the trial (P = 0.02). At the end of treatment, response rates were 62.3% for SSZ treatment compared with 47.7% for placebo treatment. The Westergren erythrocyte sedimentation rate declined more with SSZ treatment than with placebo (P < 0.0001). Adverse reactions were fewer than expected and were mainly due to nonspecific gastrointestinal complaints.

CONCLUSION

SSZ at a dosage of 2,000 mg/day is well tolerated and effective in patients with chronically active ReA.

Widespread expression of beta1 integrins in the developing chick retina: evidence for a role in migration of retinal ganglion cells

During extension of axons, critical neuronal interactions with extracellular matrix (ECM) and other cells are thought to be mediated in part by heterodimeric beta1 integrin receptors. In this report, we examine the expression and function of beta1 integrins in the developing chick retina. Expression of the beta1 subunit, assayed by in situ hybridization and antibody staining of dissociated cells, was widespread in undifferentiated neuroepithelial cells, before the initiation of axons. Expression persisted in most retinal cell layers throughout embryonic development, during and after axon extension. The repertoire of beta1-associated alpha subunits was examined using reverse transcription-polymerase chain reaction. In addition to the alpha6 and alpha8 subunits previously reported, chick homologues of the alpha2 and alpha4 subunits were detected. Developmental Northern blots revealed varying patterns of integrin subunit expression and showed that expression of beta1 and the mRNAs of its associated alpha subunits are not always coregulated during retinal development. The timing and distribution of expression suggested that beta1 integrins may be involved in other developmental events in addition to axon extension. To address functions carried out by beta1 integrins in the early retina, explanted eye cups were incubated in the presence of function blocking anti-beta1 antibody and migration of newly born retinal ganglion cells (RGCs) was assessed. RGC migration from the ventricular zone to the vitreal border was significantly inhibited, suggesting that beta1 integrins play a role in neuroblast migration in the retina.

HLA-DRB1 genes and disease severity in rheumatoid arthritis. The MIRA Trial Group. Minocycline in Rheumatoid Arthritis

OBJECTIVE

To examine the effect of alleles encoding the "shared"/"rheumatoid" epitope on rheumatoid arthritis (RA) disease severity in patients who participated in the minocycline in RA (MIRA) trial.

METHODS

Of 205 patients with a week-48 visit, blood was available for typing of HLA-DRB1 and HLA-DQB1 in 174 (85%) and successfully completed in 169 (82%). Baseline erosions were used to assess disease severity and new erosions at the last visit served as a proxy for progression.

RESULTS

At baseline, there was no association between the presence of erosive disease or rheumatoid factor status and the dose of rheumatoid epitope (homozygous, heterozygous, none) or the specific alleles identified. At the final visit, a gradient was observed for the 3 allelic subgroups (and their gene doses) in the occurrence of new erosions among the Caucasian placebo-treated, but not the minocycline-treated, patients. A treatment group/HLA-DR4 epitope interaction was demonstrated in multivariate analyses. Approximately two-thirds of African-American patients did not have the rheumatoid epitope.

CONCLUSION

HLA-DRB1 oligotyping may be useful in predicting the progression of disease in some Caucasian patients. Our study corroborates the infrequency of the epitope among African-American patients with RA.

Genetic variability in the tumor necrosis factor-lymphotoxin region influences susceptibility to rheumatoid arthritis

The major histocompatibility complex class III tumor necrosis factor-lymphotoxin (TNF-LT) region (6p21.3) was investigated as a possible susceptibility locus for rheumatoid arthritis (RA). Inheritance of five TNF microsatellite markers was determined in 50 multiplex families. Overall, 47 different haplotypes were observed. One of these, the TNF a6, b5, c1, d3, e3 (H1) haplotype, was present in 35.3% of affected, but in only 20.5% of unaffected, individuals (P < .005). This haplotype accounted for 21.5% of the parental haplotypes transmitted to affected offspring and only 7.3% not transmitted to affected offspring (P = .0003). The TNF a6 and TNF c1 alleles were individually associated with RA (P = .0005 and .0008, respectively), as were the HLA-DRB1 "shared epitope" (SE) (P = .0001) and HLA-DRB1*0401 (P = .0018). Both univariate and bivariate conditional logistic regression analysis showed significant effects of TNF c1 and SE in increasing risk to RA (P < .001). Stratification by the presence of SE indicated an independent effect of the TNFc1 allele (P = .0003) and the HLA A1, B8, DR3 extended haplotype (always TNFa2, b3, c1, d1, e3) (P = .0027) in SE heterozygotes, while the H1 haplotype was associated with RA in SE homozygotes (P = .0018). The TNF-LT region appears to influence susceptibility to RA, distinct from HLA-DR.

Inter-observer reliability of the Spondylitis Functional Index Instrument for assessing spondylarthropathies

OBJECTIVE

To study the Spondylitis Functional Index (SFI) by having two physical therapists observe patients with spondylitis perform various tasks listed on the instrument. The physical therapists' observations were compared with each other and with the self-reported abilities of the patients.

METHODS

Subjects (n = 30) were recruited from a cross-section of patients participating in a prospective randomized, multicenter, double-blind, parallel clinical trial of the efficacy of sulfasalazine on ankylosing spondylitis (n = 13), psoriatic arthritis (n = 13), and Reiter's syndrome (n = 4) conducted at the Veterans Affairs Medical Center in Salt Lake City. Percents of agreement and Cohen's kappa analysis were used to assess the reliability of the observations of the therapists and patients.

RESULTS

The overall percent of agreement between the observers on the SFI was 93%. The overall percent of agreement between observer 1 and patients on the SFI was 66% and between observer 2 and patients was 67%. The overall inter-observer reliability measured by the Pearson coefficient was 0.91 and by Cohen's kappa was 0.86. Between observer 1 and the patients the Pearson was r = 0.53 and kappa = 0.39. For observer 2 the Pearson was r = 0.52 and kappa 0.39.

CONCLUSIONS

We consider the agreement and reliability between observers to be high. The agreement and inter-observer reliability was poor between observers and patients. The SFI, as enhanced for use in this study to assess change in functional ability of patients with spondylitis, demonstrated high reliability when used by trained observers.

Temporal and spatial regulation of integrin vitronectin receptor mRNAs in the embryonic chick retina

PURPOSE

To identify integrin vitronectin receptor subunit mRNAs in the developing avian retina and to track their expression.

METHODS

Reverse transcription-polymerase chain reaction was used to identify integrin vitronectin receptor subunit mRNAs expressed in embryonic chick retina. cDNA clones encoding the beta 5 subunit were isolated and sequenced. Expression patterns of mRNAs encoding alpha v, beta 3, and beta 5 subunits were analyzed using northern analysis and in situ hybridization.

RESULTS

Integrin beta 1, beta 3, and beta 5 subunit mRNA were identified in embryonic day 6 chick retina. The sequence of chicken beta 5 was 77% identical to that of human beta 5, and sequences with known signaling functions were highly conserved. Integrin alpha v, beta 3, and beta 5 mRNAs were expressed throughout the development of the embryonic retina, with the highest levels per retina observed around the embryonic day 9. In situ hybridization showed that both beta 3 and beta 5 were expressed throughout the developing retina, particularly in undifferentiated neuroepithelial precursor cells. At later times, beta 3 was expressed uniformly throughout the retina, whereas beta 5 expression was highest in a band throughout the central retina.

CONCLUSIONS

The strong conservation of sequences with known signaling functions in chicken beta 5 suggests that it functions in a manner similar to human beta 5. Spatial expression patterns of vitronectin receptor subunits at early times of development point to a range of possible functions beyond axon outgrowth, including retinoblast proliferation, adhesion, and migration.

Human SY5Y neuroblastoma cell interactions with laminin isoforms: neurite outgrowth on laminin-5 is mediated by integrin alpha 3 beta 1

Laminin (Ln) isoforms may play important roles in neuronal development, particularly axon guidance, but neural receptors mediating interactions with Ln are not entirely understood. In this paper, we have compared the adhesive and process outgrowth activities of a human neuroblastoma cell line SY5Y on various laminin isoforms. Cell adhesion and process outgrowth were examined on murine Ln-1 (Englebreth-Holm-Swarm sarcoma laminin), human placental Ln-1 (human Ln-1[p]), human Ln-2 (merosin), human Ln-5 (kalinin/epiligrin/nicein), and human foreskin keratinocyte extracellular matrix extract (human HFK-ECM). Ln-5 was shown to evoke process outgrowth in amounts comparable to other Ln isoforms. Antibody perturbation experiments showed that adhesion and process outgrowth on murine Ln-1 was primarily mediated by the integrin alpha 1 beta 1, whereas adhesion and outgrowth on human Ln-5 and human HFK-ECM were mediated by alpha 3 beta 1. Adhesion to human Ln-1(p) and Ln-2 was not blocked by addition of anti-alpha 1 or anti-alpha 3 antibodies alone, but adhesion was partially perturbed when these antibodies were added in combination. Process outgrowth on human Ln-1(p) was blocked when either anti-alpha 3 or anti-beta 1 antibodies were added, indicating that alpha 3 beta 1 is the primary integrin heterodimer responsible for process extension on this substrate. These results demonstrate that Ln-5 and other Ln isoforms support comparable levels of adhesion and process outgrowth, but different integrin heterodimers, alone and in combination, are used by SY5Y cells to mediate responses.

Early undifferentiated connective tissue disease. IV.Musculoskeletal manifestations in a large cohort of patients with undifferentiated connective tissue diseases compared with cohorts of patients with well-established connective tissue diseases: followup analyses in patients with unexplained polyarthritis and patients with rheumatoid arthritis at baseline

OBJECTIVES

To examine the musculoskeletal manifestations in a large cohort of patients (n = 410) diagnosed with either a well-established connective tissue disease (CTD) (n = 197) or an early undifferentiated CTD (n = 213) with a symptom duration of <1 year. This study was aimed at determining the predictive value of demographic, clinical, and laboratory features on outcome in patients with unexplained polyarthritis (UPA) (from the early undifferentiated CTD cohort; n = 67) or rheumatoid arthritis (RA) (from the well-established CTD cohort; n = 57), over a 5-year followup period.

METHODS

Patients from both cohorts were assessed at years 1, 3, and 5. At the study visits, clinical data were collected in a standardized manner, and sera were obtained and stored. A priori criteria were established for patient ascertainment and diagnosis over the duration of the study. Standard statistics were used for comparisons of baseline characteristics in patients diagnosed as having systemic lupus erythematosus, RA, undifferentiated CTD, and UPA at entry into the cohorts. Baseline features in patients with UPA were examined according to the different subsequent outcomes (RA, CTD, or undifferentiated CTD, remission [nonpersistent], or persistent or active UPA). Baseline features in patients with RA whose disease remained active versus those in whom remission was attained were also examined. Two multivariable analyses, classification trees and polychotomous logistic regression, were performed to predict disease outcomes over time.

RESULTS

The overall rate of ascertainment for the 410 patients ranged from 90 % at year 1 to 71 % at year 5. Patients with established CTDs showed a tendency for more stable diagnoses than those with early undifferentiated CTDs (90-100% versus 45-70%). Consistent baseline predictors of persistent active disease among patients with RA, in both univariate and multivariable analyses, were higher joint counts for pain and tenderness and higher erythrocyte sedimentation rate (ESR). In approximately 20% of patients who were classified as having RA when they originally entered the cohort, the disease was in remission at 5 years. Twenty percent of the patients originally classified as having UPA developed RA over the duration of the study. These patients tended to be older and to have swelling of small joints at baseline. However, a consistent pattern of predictive variables could not be identified in the multivariable analyses, other than at year 1 (higher small joint counts for swelling and higher ESR).

CONCLUSION

Baseline features (joint counts, and ESR) among RA patients were variously predictive of persistently active disease at years 1-5. Consistent baseline predictors of outcome among patients with UPA only emerged at year 1. Remission occurred in approximately 20% of RA patients, whereas a similar percentage of patients with UPA developed RA. These findings have implications with regard to treatment decisions in patients with early RA and/or UPA.

Integrin alpha 2 beta 1 mediates interactions between developing embryonic retinal cells and collagen

In the developing nervous system, the extracellular matrix provides a source of extrinsic cues to guide determination of cell fate, neuroblast migration, axon outgrowth and synapse formation. In the neural retina, undifferentiated neuroepithelial precursor cells contact extracellular matrix that contains multiple collagen types. Collagens have been shown to support retinal cell adhesion and neurite outgrowth, but the integrin receptors mediating neuronal responses are not understood. Here we provide evidence that integrin alpha 2 beta 1 acts as a collagen receptor in the developing avian retina and examine its expression pattern. Using a recently described monoclonal antibody, MEP-17, alpha 2 protein was detected in the developing retina by immunofluorescence in tissue sections and dissociated cells, and by immunoprecipitation. At embryonic day 4 (E4), when the majority of retinal cells are undifferentiated neuroepithelial cells, alpha 2 immunoreactivity in sections was widespread and about half of cells dissociated in culture were alpha 2 positive. At E6, after the retinal ganglion cell layer had differentiated, immunoreactivity in sections decreased in the central, more developed portion of the retina and 25% of dissociated cells were alpha 2 positive. E6 retinal ganglion cells, identified by neurofilament immunoreactivity, did not express detectable alpha 2 immunoreactivity. Immunoprecipitation experiments using E6 extracts demonstrated that the alpha 2 subunit was paired with the beta 1 integrin subunit. By E12, alpha 2 immunoreactivity in sections was confined to the extreme peripheral retina, although the antigen may be masked since expression levels comparable to or slightly higher than E6 could be detected in dissociated cells and extracts. By employing function blocking antibodies, it was shown that alpha 2 beta 1 integrin is necessary for cell adhesion and process outgrowth by embryonic retinal cells on collagens I and IV. Although alpha 2 expression continued through E12, alpha 2 activity was down regulated with increasing embryonic age, since alpha 2-dependent adhesion and outgrowth declined. These data suggest a role for alpha 2 beta 1 in neuroepithelial cell interactions with collagen rather than for axon extension by retinal ganglion cells.

Glucose-induced alteration of integrin expression and function in cultured human mesangial cells

Alteration in mesangial volume, due to an increase of the matrix surrounding mesangial cells, is a hallmark indicator of nephropathy in diabetes. Mesangial cells may also play a significant role in the development of nephropathy. Therefore, we examined the effect of glucose on the expression of integrins by cultured human mesangial cells and their ability to interact with collagen IV, a major component of the mesangial matrix. Human mesangial cells were grown in 5 and 25 mM glucose and their integrin profile was examined by immunoprecipitation and flow cytometry in each experimental condition. The results indicate that when mesangial cells were grown in 25 mM glucose, the expression of integrin subunit alpha 2, was increased, while the alpha 1 subunit was considerably decreased, as compared to cells grown in 5 mM glucose. Additionally, mesangial cells were tested for their ability to adhere to collagen IV in a solid-phase assay in the presence of neutralizing antibodies to integrin subunits. The results of these experiments indicate that both alpha 1 and alpha 2 complexed to beta 1 (alpha 2 beta 1 and alpha 1 beta 1) are major mesangial cell receptors for adhesion to collagen IV both in 5 and 25 mM glucose. The two receptors act in concert to mediate adhesion of mesangial cells to type IV collagen. When cell surface expression of the alpha 1 subunit in 25 mM glucose was reduced, the alpha 2 subunit was involved in adhesion to a greater extent than it was in 5 mM glucose. Immunoperoxidase histochemical studies localized both alpha 1 and alpha 2 integrin subunits in the mesangium of normal adult kidneys, suggesting that in vivo interaction with collagen IV could involve both of these receptors. These observations suggest that glucose-induced alterations in integrin expression may modify the ability of mesangial cells to interact with collagen IV.

Differential localization and functional role of calsequestrin in growing and differentiated myoblasts

Calsequestrin (CSQ) is the low affinity, high capacity Ca(2+)-binding protein concentrated within specialized areas of the muscle fiber sarcoplasmic reticulum (a part of the ER) where it is believed to buffer large amounts of Ca2+. Upon activation of intracellular channels this Ca2+ pool is released, giving rise to the [Ca2+]i increases that sustain contraction. In order to investigate the ER retention and the functional role of the protein, L6 rat myoblasts were infected with a viral vector with or without the cDNA of chicken CSQ, and stable clones were investigated before and after differentiation to myotubes. In the undifferentiated L6 cells, expression of considerable amounts of heterologous CSQ occurred with no major changes of other ER components. Ca2+ release from the ER, induced by the peptide hormone vasopressin, remained however unchanged, and the same occurred when other treatments were given in sequence to deplete the ER and other intracellular stores: with the Ca2+ pump blocker, thapsigargin; and with the Ca2+ ionophore, ionomycin, followed by the Na+/H+ ionophore, monensin. The lack of effect of CSQ expression on the vasopressin-induced [Ca2+]i responses was explained by immunocytochemistry showing the heterologous protein to be localized not in the ER but in large vacuoles of acidic content, positive also for the lysosomal enzyme, cathepsin D, corresponding to a lysosomal subpopulation. After differentiation, all L6 cells expressed small amounts of homologous CSQ. In the infected cells the heterologous protein progressively decreased, yet the [Ca2+]i responses to vasopressin were now larger with respect to both control and undifferentiated cells. This change correlated with the drop of the vacuoles and with the accumulation of CSQ within the ER lumen, where a clustered distribution was observed as recently shown in developing muscle fibers. These results provide direct evidence for the contribution of CSQ, when appropriately retained, to the Ca2+ capacity of the rapidly exchanging, ER-located Ca2+ stores; and for the existence of specific mechanism(s) (that in L6 cells develop in the course of differentiation) for the ER retention of the protein. In the growing L6 myoblasts the Ca(2+)-binding protein appears in contrast to travel along the exocytic pathway, down to post-Golgi, lysosome-related vacuoles which, based on the lack of [Ca2+]i response to ionomycin-monensin, appear to be incompetent for Ca2+ accumulation.

Non-linkage of a T-cell receptor gamma chain microsatellite (D7S485) to rheumatoid arthritis in multiplex families

A highly informative microsatellite marker, D7S485, from the T-cell receptor gamma (TCRG) locus, has been used to study segregation of TCRG genes in 26 multiplex rheumatoid arthritis (RA) families. We used the sib-pair method to assess excess identity-by-descent sharing among affected members in these families and the LINKAGE package of programs was used to calculate two-point lod scores for the D7S485 marker. There was no evidence for segregation of TCRG genes with RA in affected siblings and significantly negative lod scores were obtained from linkage analyses using both autosomal dominant and recessive models of inheritance.

Minocycline in rheumatoid arthritis. A 48-week, double-blind, placebo-controlled trial. MIRA Trial Group

OBJECTIVE

To assess the safety and efficacy of minocycline in the treatment of rheumatoid arthritis.

DESIGN

A double-blind, randomized, multicenter, 48-week trial of oral minocycline (200 mg/d) or placebo.

SETTING

6 clinical centers in the United States.

PATIENTS

219 adults with active rheumatoid arthritis who had previous limited treatment with disease-modifying drugs.

MEASUREMENTS

As the primary outcomes, 60 diarthrodial joints were examined for tenderness, and 58 joints were examined for swelling (hips excluded). Grip strength, evaluator's global assessment, morning stiffness, Modified Health Assessment Questionnaire, patient's global assessment, hematocrit, erythrocyte sedimentation rate, platelet count, and IgM rheumatoid factor levels were also assessed; radiographs of both hands and wrists were taken.

RESULTS

109 and 110 patients were randomly assigned to receive minocycline and placebo, respectively. At entry, demographic, clinical, and laboratory measurements were similar in both groups. Most patients had mild to moderate disease activity and some evidence of destructive disease. At the week 48 visit, 79% of the minocycline group and 78% of the placebo group continued to receive the study medication. At 48 weeks, more patients in the minocycline group than in the placebo group showed improvement in joint swelling (54% and 39%) and joint tenderness (56% and 41%) (P < 0.023 for both comparisons). The minocycline group also showed greater improvement in hematocrit, erythrocyte sedimentation rate, platelet count, and IgM rheumatoid factor levels (all P values < 0.001), and more patients receiving minocycline had laboratory values within normal ranges at 48 weeks. For the remaining outcomes, P values ranged from 0.04 to 0.76, all greater than the critical value of 0.005 (Bonferroni adjustment for multiple comparisons). The frequency of reported side effects was similar in both groups, and no serious toxicity occurred.

CONCLUSIONS

Minocycline was safe and effective for patients with mild to moderate rheumatoid arthritis. Its mechanisms of action remain to be determined.

HLA-linked rheumatoid arthritis

Twenty-eight pedigrees were ascertained through pairs of first-degree relatives diagnosed with rheumatoid arthritis (RA). RA was confirmed in 77 pedigree members including probands; the absence of disease was verified in an additional 261 pedigree members. Pedigree members were serologically typed for HLA. We used likelihood analysis to statistically characterize the HLA-linked RA susceptibility locus. The genetic model assumed tight linkage to HLA. The analysis supported the existence of an HLA-linked RA susceptibility locus, estimated the susceptibility allele frequency as 2.16%, and estimated the lifetime penetrance as 41% in male homozygotes and as 48% in female homozygotes. Inheritance was recessive in males and was nearly recessive in females. In addition, the analysis attributed 78% of the variance within genotypes to genetic or environmental effects shared by siblings. The genetic model inferred in this analysis is consistent with previous association, linkage, and familial aggregation studies of RA. The inferred HLA-linked RA susceptibility locus accounts for approximately one-half of familial RA, although it accounts for only approximately one-fifth of the RA in the population. Although other genes may account for the remaining familial RA, a large portion of RA cases may occur sporadically.

Comparison of hydroxychloroquine and placebo in the treatment of the arthropathy of mild systemic lupus erythematosus

OBJECTIVE

To compare the relative safety and efficacy of hydroxychloroquine (HCQ) and placebo (Pl) in the treatment of the articular complaints of systemic lupus erythematosus (SLE).

METHODS

Seventy-one patients with mild SLE requiring < or = 10 mg of prednisone or equivalent daily and with arthritis or arthralgias were entered into a 48-week prospective, controlled, double blind multicenter trial and randomly assigned to either HCQ or Pl.

RESULTS

Both HCQ and Pl were well tolerated in the 48-week trial. There were no remissions. With the exception of the patient assessment of joint pain, all other joint measures were similar between the groups. Twenty-nine patients withdrew before the end of the trial although only 2 patients withdrew for adverse drug effects.

CONCLUSION

Our study found subjective pain relief as the only statistically significant difference in joint count variables from HCQ in the treatment of the articular manifestations of SLE.

Functional identification of integrin laminin receptors that mediate process outgrowth by human SY5Y neuroblastoma cells

Treatment of the human neuroblastoma cell line SY5Y with nerve growth factor (NGF) induces terminal neuronal differentiation of a subpopulation of cells which can be selected by treatment with a DNA synthesis inhibitor. We have examined the interactions of naive (untreated) and NGF-differentiated SY5Y cells with laminin, and identified integrin receptors that mediate laminin-induced process outgrowth. Differentiated cells displayed a greater capacity for process extension, which correlated with increased expression of integrin laminin receptors. Both naive and differentiated cells expressed integrins alpha 1/beta 1, alpha 2/beta 1, and alpha 3/beta 1 but the differentiated population expressed about 5-fold higher levels of alpha 1/beta 1 and about 2-fold more alpha 2/beta 1 and alpha 3/beta 1 on their surface. Function blocking monoclonal antibodies were used to identify integrin receptors mediating process outgrowth. The anti-alpha 1 monoclonal antibody SR84 was shown to block alpha 1 function and inhibit process outgrowth on laminin. Despite the presence of multiple integrins which have been shown to bind laminin in other cell types, alpha 1/beta 1 mediated the majority of process outgrowth in both naive and differentiated cells, with a minor role played by alpha 3/beta 1. These data indicate that alpha 1/beta 1 function is required for process outgrowth on laminin by SY5Y cells and suggest that increased expression may be a crucial aspect of neuronal differentiation.

Comparison of aminobenzoate potassium and placebo in the treatment of scleroderma

OBJECTIVE

To determine the safety and efficacy of aminobenzoate potassium (KPAB) in treating the skin manifestations of scleroderma.

METHODS

Via a 48-week prospective, randomized, double blind, placebo controlled trial we compared the efficacy of KPAB 12 g/day with matching placebo. Outcome measures included skin mobility and thickening scores, patient and physician global assessments and, measurements of maximal oral aperture and hand range of motion.

RESULTS

Of 146 patients who entered the study, 76 (52%) completed. Demographics of the study population included age 49 +/- 13 years, 83% women, mean (range) disease duration was 104 (7-600) months. There were no differences in the demographics of the KPAB vs placebo nor the group that completed the study compared with the withdrawal group. There were no clinical or statistically significant differences between the KPAB and the placebo treated groups in any of the outcome measures. Subgroup analyses of skin mobility and skin thickening based on age, extent of disease, severity of disease, duration of disease and involved vs uninvolved skin were performed, but no differences were noted. The overall compliance to the medical regimen was > or = 75% in 93% of patients completing the study. Eighteen patients in the KPAB group and 6 placebo patients withdrew due to adverse drug reactions (ADR). The most common withdrawals for ADR were gastrointestinal intolerance and headaches. All ADR resolved following withdrawal of medication.

CONCLUSION

KPAB did not alter the skin changes of scleroderma in a group of patients with relatively longstanding stable disease. KPAB was reasonably well tolerated in this group of patients.

The effect of long-term methotrexate therapy on hepatic fibrosis in rheumatoid arthritis

OBJECTIVE

To evaluate the progression of hepatic fibrosis in patients with rheumatoid arthritis (RA) treated with methotrexate (MTX).

METHODS

Fifteen patients receiving MTX for RA were prospectively studied by electron microscopic analysis of biopsy specimens.

RESULTS

Five of the 15 patients had evidence of increased hepatic collagen after 2 years of MTX therapy.

CONCLUSION

Hepatic fibrosis may progress in a subgroup of RA patients treated with MTX.

Comparison of naproxen and acetaminophen in a two-year study of treatment of osteoarthritis of the knee

OBJECTIVE

To compare the relative safety and efficacy of naproxen and acetaminophen in the treatment of osteoarthritis (OA) of the knee. The major outcome measures were radiographic progression and withdrawal from the trial due to lack of efficacy.

METHODS

One hundred seventy-eight patients with OA of the knee were enrolled in a 2-year prospective, controlled, double-blind multicenter trial and were randomly assigned to receive acetaminophen (ACT) or naproxen (NPX) treatment.

RESULTS

After 6 weeks of treatment, modest improvement in pain on motion and in physician's global assessment was seen in both the ACT and the NPX groups, and the NPX group also had modest improvement in pain at rest and in 50-foot walk time. Sixty-two patients completed the 2-year study. Among these patients, radiographic progression was similar in the 2 treatment groups. Withdrawal from the trial due to lack of drug efficacy was slightly more frequent among patients in the ACT group (22% versus 16%), but withdrawal due to adverse drug effects was slightly more common in the NPX group (23% versus 18%).

CONCLUSION

The efficacy of ACT treatment and NPX treatment was similar, although it was slightly better for NPX. The toxicity rate was slightly lower with ACT. However, the high rate of withdrawal in both treatment groups suggests that neither is satisfactory for the treatment of OA.

Expression of the calsequestrin gene in chicken cerebellum Purkinje neurons

Intracellular rapidly exchanging Ca2+ stores are identified and defined in terms of intralumenal low-affinity, high-capacity Ca(2+)-binding proteins, of which calsequestrin (CS) is the prototype in striated muscles. In chicken striated muscles, there is a single gene for CS [Choi and Clegg (1990) Dev. Biol. 142, 169-177]. In the chicken brain, the gene for CS was found to be selectively expressed in Purkinje neurons, as judged by Northern blotting, in situ hybridization and immunocytochemistry. The synthetic machinery for CS was found to be restricted to the cell body, i.e. excluded from dendrites and axon.

Characterization of a beta-nerve growth factor expression vector for mammalian cells

A mammalian expression vector that directs expression of murine beta-nerve growth factor (beta-NGF) from a murine sarcoma virus long terminal repeat (LTR) promoter element was constructed and characterized. The vector, designated pLTRSNGF, was stably transfected into murine L-cells, and beta-NGF mRNA and protein levels were quantified and compared to endogenous levels in control L-cells. Transfection of pLTRSNGF resulted in an approximate doubling of both beta-NGF mRNA and mature beta-NGF protein secreted into the media. Transfection of pLTRSNGF into rat PC 12 cells resulted in colonies of autocrine-differentiating cells that extended dense networks of neurites in the absence of added NGF, indicating that the beta-NGF produced from the vector is biologically active.

Early undifferentiated connective tissue disease: III. Outcome and prognostic indicators in early scleroderma (systemic sclerosis)

OBJECTIVE

To characterize the course of early scleroderma and to delineate prognostic factors present within 1 year of disease onset that might identify patients at high risk.

DESIGN

Inception cohort study.

SETTING

Ten university-based rheumatology clinics participating in the Cooperative Systematic Studies of Rheumatic Diseases Program.

PATIENTS

Forty-eight patients who had had scleroderma for less than 1 year.

MEASUREMENTS

Fifteen patients with early scleroderma who died were compared with those still living during the initial study period (1982 to 1992). Kaplan-Meier survival estimation and Cox proportional hazards analysis were used to analyze baseline variables for their ability to predict survival duration.

RESULTS

Eight of 15 deaths were due to cardiac or pulmonary system failure. The estimated 5-year survival rate was 68%. Baseline factors that were the most predictive of a poor outcome included the presence of abnormal cardiopulmonary signs and abnormal urine sediment (pyuria, hematuria).

CONCLUSION

Evidence of early cardiopulmonary disease, renal disease, inflammation, or immune activation may identify a subset of patients with scleroderma who will experience rapidly progressive disease and early death.

Comparison of auranofin, methotrexate, and the combination of both in the treatment of rheumatoid arthritis. A controlled clinical trial

OBJECTIVE

To compare the relative safety and efficacy of auranofin (AUR), methotrexate (MTX), and the combination of both in the treatment of active rheumatoid arthritis (RA).

METHODS

Three hundred thirty-five patients with active RA were entered into a 48-week, prospective, controlled, double-blind, multicenter trial and were randomly assigned to 1 of 3 treatment groups.

RESULTS

Two hundred eleven patients completed the trial. No remissions were seen, and there were no statistically significant differences among the treatment groups in the clinical or laboratory variables measured. Patients taking AUR alone had a slower onset of response than did patients taking MTX alone or in combination. Withdrawals because of adverse drug reactions were slightly more common for those taking combination therapy, but the differences were not statistically significant. Withdrawals because of lack of response were more common for single-drug therapy, with the difference between AUR and the combination reaching statistical significance. No unexpected adverse drug effects were identified, and all reactions resolved without sequelae.

CONCLUSION

Except for fewer withdrawals because of lack of response, combination therapy did not demonstrate any advantage in efficacy over single-drug treatment within the time frame of the study.