Increased Diagnostic Accuracy of the Labial Gland Biopsy in Primary Sjögren Syndrome When Multiple Histopathological Features Are Included

OBJECTIVE

The aim of this study was to evaluate the diagnostic accuracy of the labial salivary gland biopsy based on multiple histopathological features in patients with suspected primary Sjögren syndrome (pSS).

METHODS

Patients from a diagnostic sicca cohort with clinically suspected pSS who underwent a labial gland biopsy were included. Patients were categorized as having pSS or non-Sjögren syndrome sicca (non-SS sicca) based on vignettes scored by an expert panel. Labial gland biopsies were analyzed for the presence of four histopathological features: focus score (FS) ≥1, prelymphoepithelial and lymphoepithelial lesions, immunoglobulin G plasma cell shift, and germinal centers. Sensitivity and specificity of histologic features were calculated, and the optimal cutoff value for the number of histopathological features needed to diagnose pSS was determined with receiver operating curve analysis.

RESULTS

A total of 38 patients were categorized as having pSS and 65 as having non-SS sicca. In labial gland biopsies of patients with pSS, the prevalence of FS ≥1 was 82%, followed by 68% for pre-lymphoepithelial and lymphoepithelial lesions, 63% for plasma cell shift, and 24% for germinal centers. Although FS ≥1 showed the highest sensitivity for patients with pSS (82%), specificity was higher for the other three features (98%-100%). The presence of two or more (of four) histopathological features had almost comparable sensitivity to FS alone, but specificity increased with 12% to 100%. For fulfillment of American College of Rheumatology/EULAR criteria, specificity increased from 84% to 95% when an abnormal biopsy was defined by the presence of two or more histopathological features instead of FS ≥1 only.

CONCLUSION

The diagnostic accuracy of the labial gland biopsy increases when other histopathological features besides FS are taken into account, by reducing the number of false-positive biopsies.

Longitudinal evaluation of major salivary gland functioning in Sjögren's disease patients in a prospective standard-of-care cohort

OBJECTIVES

To evaluate changes in major salivary gland functioning over time using salivary gland ultrasonography (SGUS), salivary flow measurements (sialometry), and patient-reported outcome measures (PROMs) in patients diagnosed with primary Sjögren's disease (SjD).

METHODS

Consecutive outpatients from the ongoing prospective REgistry of Sjögren Syndrome LongiTudinal (RESULT) cohort, all fulfilling the ACR-EULAR classification criteria for SjD, were included. SGUS images assessed with the Hocevar and OMERACT scoring system, unstimulated and stimulated whole saliva (UWS/SWS), unstimulated and stimulated submandibular/sublingual saliva (uSMSLS/sSMSLS) and parotid saliva, EULAR Sjögren's Syndrome Patient Reported Index (ESSPRI) general dryness, oral dryness, and Xerostomia Inventory were assessed at baseline (BL), 2-year (Y2) and 5-year (Y5) follow-up.

RESULTS

In total, BL and Y2 data were available for 253 patients and 75 patients had already reached Y5. At group level, SGUS Hocevar (i.e., mean±SD: 22±10 at BL, 22±10 at Y2 and 23±10 at Y5), OMERACT scores, UWS, SWS and PROMs remained stable over time (all p>0.05). Slightly decreased uSMSLS (p=0.025) and sSMSLS (p=0.004) were observed at Y5. At individual patient level, a similar proportion showed an increase or decrease of ≥25% for Hocevar, UWS and SWS. At baseline, poor associations were observed between SGUS and PROMs and fair associations between sialometry and PROMs. Over time, changes in objective assessments did not correlate with changes in PROMs.

CONCLUSIONS

Overall, major salivary gland functioning assessed with SGUS, sialometry and PROMs did not change significantly up to 5 years of follow-up in a standard-of-care cohort of SjD patients from daily clinical practice.

Can ultrasound of the major salivary glands differentiate Sjögren's disease from its major mimics?

OBJECTIVES

Ultrasound of the major salivary glands (SGUS) is widely used to assess the major salivary glands in Sjögren's disease (SjD). Little is known, however, regarding the diagnostic accuracy of SGUS to differentiate SjD from its mimics. This study aims to investigate the diagnostic accuracy of SGUS in differentiating SjD from other diseases with salivary gland involvement.

METHODS

SGUS was performed in 20 consecutive patients with SjD and 20 consecutive patients with well-established systemic disease, i.e., with either sarcoidosis, amyloidosis, HIV infection or chronic HCV infection. Images were scored independently by two blinded observers using the Hocevar scoring system. Diagnostic accuracy to discriminate between the patient (sub-)groups was explored.

RESULTS

The accuracy of SGUS to differentiate SjD from other systemic diseases was excellent (area under ROC curve of 0.91). The optimal cut-off value to define positive or negative ultrasound for SS was 15. Sensitivity, specificity, positive predictive value and negative predictive value were high, varying from 85-90%, and diagnostic odds ratio was 51. SGUS was positive in the vast majority of SjD patients (n=18), but also in 2 patients with HIV infection and one patient with sarcoidosis. SGUS score differed significantly between patients with SjD and other systemic diseases (median 27 vs. 10, p<0.001) as well as between SjD patients and patients with either sarcoidosis, amyloidosis, HIV or HCV infection (all p<0.05).

CONCLUSIONS

This study indicates that SGUS has a potentially high diagnostic accuracy to discriminate SjD from systemic diseases which can also cause salivary gland involvement.

Capillary microscopy is a potential screening method for connective tissue disease in children with Raynaud's phenomenon

BACKGROUND

Nailfold capillary microscopy (NCM) is a cornerstone in the diagnosis of Systemic Sclerosis (SSc) in adulthood. Although Raynaud's phenomenon (RP) is very common in childhood, studies on diagnostic methods to differentiate between primary RP (PRP) and secondary RP (SRP) at a young age are scarce. The aim of this study was to determine the value of NCM in differentiating between PRP and SRP in children and adolescents with RP.

METHODS

In this nested case-control study, 83 patients diagnosed with RP and having underwent NCM in childhood were retrospectively included. Based on whether they were diagnosed with a connective tissue disease (CTD) during follow-up, patients were classified as PRP or SRP. NCM was performed by a vascular technician. PRP and SRP patients were compared on demographics, NCM and serology. Variables associated with SRP were included in a multivariate logistic regression model. Predictive values were calculated for NCM, ANA positivity and the combination of NCM and ANA positivity.

RESULTS

At the time of the NCM, the mean age of the RP patients was 15.4 ± 2.3 years. Of these patients, 78.3% were classified as PRP and 21.7% as SRP at mean follow-up of 6.4 ± 3.20 years. CTDs were miscellaneous, with only one patient having developed SSc. Of the NCM parameters, only capillary loss was associated with SRP (p = 0.01). In a multivariate logistic regression model including ANA, capillary loss was not a predictor of SRP. In a model without ANAs, capillary loss was an independent predictor (OR = 3.98, CI 95% 1.22-12.99). Capillary loss had a sensitivity of 44.4% and a specificity of 84.4% for SRP. ANA combined with capillary loss had a sensitivity of 66.7% and a specificity of 85.7%.

CONCLUSION

Whereas RP in adulthood is most strongly associated with SSc, children with RP seem to be at risk for developing other CTDs with less apparent NCM abnormalities. Of all NCM findings, only capillary loss was predictive for SRP. NCM did not add to the predictive value of ANA screening. However, with a specificity of 84.4% and being non-invasive, NCM shows potential as a screening method for SRP. More research with a larger study population is required before drawing conclusions.

Histopathology, salivary flow and ultrasonography of the parotid gland: three complementary measurements in primary Sjögren's syndrome

OBJECTIVE

The involvement of salivary glands in primary Sjögren's syndrome (pSS) can be assessed in different ways: histopathology, salivary flow and ultrasonography. To understand the relative value of these different approaches, it is crucial to understand the relationship between them. As we routinely perform these three modalities in the parotid gland for disease evaluation, our aim was to investigate the construct validity between these modalities in one and the same gland.

METHODS

Consecutive sicca patients underwent a multidisciplinary diagnostic work-up including parotid gland biopsy, collection of parotid gland-specific saliva and parotid gland ultrasonography. Patients who were classified as pSS according to the ACR-EULAR criteria were included. Construct validity was assessed using Spearman's correlation coefficients.

RESULTS

The 41 included pSS patients completed a full work-up within mean time interval of 2.6 months. Correlations between histopathological features and stimulated parotid salivary flow were fair (ρ=-0.123 for focus score, and ρ=-0.259 for percentage of CD45+ infiltrate). Likewise, poor correlations were observed between stimulated parotid salivary flow and parotid ultrasonography (ρ=-0.196). Moderate to good associations were found between the histopathological items focus score and percentage of CD45+ infiltrate, with parotid ultrasound scores (total ultrasound score: ρ = 0.510 and ρ = 0.560; highest for homogeneity: ρ = 0.574 and ρ = 0.633).

CONCLUSION

Although pSS associated ultrasonographic findings did correlate with histopathological features, the three modalities that evaluate salivary gland involvement assess different (or at best partly related) constructs. Therefore, histopathology, salivary flow and ultrasonography are complementary measurements and cannot directly replace each other in the work-up of pSS.

[Sympathicotomy in patients with drug resistant Raynaud's phenomenon]

Raynaud's phenomenon (RP) is a disorder of the microvasculature which causes poor blood flow to the digits. This disorder is common in young females and may be associated with several underlying connective tissue diseases including systemic sclerosis. Although RP may have a tremendous impact on quality of life, treatment options are limited. Conventional medical treatment mainly consists of vasodilatory drugs, which are not effective in all patients and may induce undesired side effects. The current clinical lesson describes three patients with severe RP who all underwent a novel, minimally invasive, single-port thoracoscopic sympathicotomy (SPTS). Although this procedure seems promising in patients with treatment-resistant RP, as shown with patients A and B, future research has yet to show what the long-term effects are.

Clinical Phenotyping of Primary Sjögren Syndrome Patients Using Salivary Gland Ultrasonography: Data From the RESULT Cohort

OBJECTIVE

To investigate salivary gland ultrasound (SGUS) abnormalities in relation to clinical phenotype and patient characteristics, disease activity, and disease damage in patients with primary Sjögren syndrome (pSS).

METHODS

Consecutive outpatients included in our REgistry of Sjögren Syndrome LongiTudinal (RESULT) cohort were selected. Patients with pSS who were included were classified according to the American College of Rheumatology/European League Against Rheumatism (EULAR) criteria and underwent full ultrasonographic examination (Hocevar score 0-48) at baseline. Total SGUS scores of ≥ 15 were considered positive. Patient characteristics, disease activity, and disease damage were compared between the different SGUS groups.

RESULTS

In total, 172 of 186 patients with pSS were eligible, of whom 136 (79%) were SGUS positive. Compared with patients who were SGUS negative, SGUS-positive patients had significantly longer disease duration, higher EULAR Sjögren Syndrome Disease Activity Index, higher Sjögren Syndrome Disease Damage Index, and were more likely to have a positive parotid gland biopsy, anti-SSA/SSB antibodies, and abnormal unstimulated whole saliva (UWS) and ocular staining score (OSS), and higher levels of IgG and rheumatoid factor. Regarding patient-reported outcome measurements (PROM), patients who were SGUS positive scored significantly lower on the EULAR Sjögren Syndrome Patient-Reported Index for fatigue and pain, and more often found their disease state acceptable compared with patients who were SGUS negative. SGUS total score showed significant associations with various clinical and serological variables, and with PROM. Highest associations were found for UWS (ρ = -0.551) and OSS (ρ = 0.532).

CONCLUSION

Patients who were SGUS positive show a distinct clinical phenotype in all aspects of the disease compared with patients who were SGUS negative: clinical, functional, serological, and PROM. SGUS could be a helpful tool in selecting patients for clinical trials and estimating treatment need.

Incorporation of Salivary Gland Ultrasonography Into the American College of Rheumatology/European League Against Rheumatism Criteria for Primary Sjögren's Syndrome

Objective

To assess whether the addition of salivary gland ultrasonography (SGUS) or replacement of current criteria items by SGUS influences the performance of the American College of Rheumatology (ACR)/European League Against Rheumatism (EULAR) criteria for primary Sjögren's syndrome.

Methods

Included were consecutive patients with complete data on all ACR/EULAR items (n = 243) who underwent SGUS in our primary Sjögren's syndrome expertise center. Clinical diagnosis by the treating physician was used as the gold standard. Separate analyses were performed for patients who underwent labial or parotid gland biopsies. The average score for hypoechogenic areas in 1 parotid and 1 submandibular gland was determined (range 0–3). Next, performance of the ACR/EULAR criteria was evaluated after addition of SGUS or replacement of current items by SGUS.

Results

Receiver operating characteristic analysis showed an optimal cutoff value of ≥1.5 for SGUS. The optimal weight for SGUS positivity was 1. Cutoff for ACR/EULAR fulfilment remained ≥4. In patients who underwent a labial gland biopsy (n = 124), the original criteria showed an area under the curve (AUC) of 0.965, sensitivity of 95.9%, and specificity of 92.2%. After the addition of SGUS, the AUC was 0.966, with a sensitivity of 97.3% and specificity of 90.2%. In patients who underwent a parotid gland biopsy (n = 198), similar results were found. Sensitivity of the criteria decreased substantially when SGUS replaced salivary gland biopsy or anti‐SSA antibodies, while performance remained equal when SGUS replaced the ocular staining score, Schirmer's test, or unstimulated whole saliva flow.

Conclusion

Validity of the ACR/EULAR criteria remains high after incorporation of SGUS. With SGUS, clinicians are offered a larger array of tests to evaluate fulfillment of the ACR/EULAR criteria.

How do patients with systemic sclerosis experience currently provided healthcare and how should we measure its quality?

Objectives

To gain insight into SSc patients’ perspective on quality of care and to survey their preferred quality indicators.

Methods

An online questionnaire about healthcare setting, perceived quality of care (CQ index) and quality indicators, was sent to 2093 patients from 13 Dutch hospitals.

Results

Six hundred and fifty patients (mean age 59 years, 75% women, 32% limited cutaneous SSc, 20% diffuse cutaneous SSc) completed the questionnaire. Mean time to diagnosis was 4.3 years (s.d. 6.9) and was longer in women compared with men (4.8 (s.d. 7.3) vs 2.5 (s.d. 5.0) years). Treatment took place in a SSc expert centre for 58%, regional centre for 29% or in both for 39% of patients. Thirteen percent of patients was not aware of whether their hospital was specialized in SSc. The perceived quality of care was rated with a mean score of 3.2 (s.d. 0.5) (range 1.0–4.0). There were no relevant differences between expert and regional centres. The three prioritized process indicators were: good patient-physician interaction (80%), structural multidisciplinary collaboration (46%) and receiving treatment according to SSc guidelines (44%). Absence of disease progression (66%), organ involvement (33%) and digital ulcers (27%) were the three highest rated outcome indicators.

Conclusion

The perceived quality of care evaluated in our study was fair to good. No differences between expert and regional centres were observed. Our prioritized process and outcome indicators can be added to indicators suggested by SSc experts in earlier studies and can be used to evaluate the quality of care in SSc.

Abatacept treatment for patients with early active primary Sjögren's syndrome: a single-centre, randomised, double-blind, placebo-controlled, phase 3 trial (ASAP-III study)

BACKGROUND

Several small open-label studies have suggested efficacy of abatacept-a co-stimulation inhibitor-in patients with primary Sjögren's syndrome. These promising results warranted further evaluation. We therefore aimed to further assess the safety and efficacy of abatacept compared with placebo in patients with primary Sjögren's syndrome.

METHODS

We did a single-centre, randomised, double-blind, placebo-controlled, phase 3 trial at the University Medical Center Groningen (Groningen, Netherlands). We included patients with primary Sjögren's syndrome fulfilling the American-European Consensus Group criteria, aged 18 years or older, with positive salivary gland biopsies, time from diagnosis of 7 years or less, and a European League Against Rheumatism Sjögren's Syndrome Disease Activity Index (ESSDAI) score of 5 or more. Independent pharmacists randomly allocated patients (1:1) to either the abatacept group or placebo group using a computer-generated sequence stratified by previous use of disease-modifying anti-rheumatic drugs. Patients received at-home subcutaneous injections of abatacept (125 mg) or placebo once a week for 24 weeks. The primary outcome was the between-group difference in ESSDAI score at week 24. Efficacy was analysed in patients who received at least one drug dose and for whom post-baseline data were collected. Safety was analysed in all patients who received at least one drug dose.

FINDINGS

Between Aug 14, 2014, and Aug 23, 2018, 580 patients were reviewed for eligibility, of which 80 patients were randomly assigned to receive study treatment. Efficacy was analysed in 40 patients receiving abatacept and 39 patients receiving placebo (one patient in this group was lost to follow-up). The primary outcome did not significantly differ between the treatment groups. The adjusted mean difference in ESSDAI score at week 24 between the abatacept group and placebo group was -1·3 (95% CI -4·1 to 1·6). No deaths or treatment-related serious adverse events occurred. In 38 (95%) of 40 patients in the abatacept group, 103 adverse events occurred, including one serious adverse event and 46 infections. In 38 (95%) of 40 patients in the placebo group, 87 adverse events occurred, including four serious adverse events and 49 infections.

INTERPRETATION

On the basis of this trial, we cannot recommend abatacept treatment as standard of care to reduce systemic disease activity in patients with primary Sjögren's syndrome. Further studies should evaluate whether patients with specific clinical manifestations and biological characteristics might benefit from abatacept treatment.

FUNDING

Bristol-Myers Squibb.

Assessing recovery after cold challenge and thumb involvement can help to rule out systemic sclerosis in patients presenting with Raynaud's phenomenon

Objective: Our aim was to study whether recovery from a Raynaud's attack and involvement of the thumb are differentiators for systemic sclerosis (SSc) in patients with Raynaud's phenomenon (RP).Method: A stepwise cooling and recovery procedure was performed, provoking an RP attack, in patients with primary Raynaud's phenomenon (PRP, n = 68) and SSc (n = 18). During the procedure, the perfusion of all five fingers during cooling and recovery was assessed by photoelectric plethysmography.Results: In SSc patients, perfusion after 10 min in one or more fingers was more frequently not restored than in PRP patients (p = 0.001), with a negative predictive value of 98%. The thumb was more frequently involved in SSc patients (p = 0.036), with a negative predictive value of 95%. Positive predictive values were low.Conclusions: In patients with RP, when there is restoration of perfusion in all fingers after 10 min or when the thumb is spared, the presence of an underlying SSc is very unlikely. Although these results need to be validated in a clinical setting in a larger prospective study, these signs can help physicians to select additional testing for SSc in RP patients.

Abnormal Nailfold Capillaroscopy Is Common in Patients with Connective Tissue Disease and Associated with Abnormal Pulmonary Function Tests

OBJECTIVE

To assess the presence of a systemic sclerosis (SSc) pattern on nailfold capillary microscopy (NCM) in patients with Raynaud phenomenon (RP) and to explore its association with abnormal pulmonary function tests (PFT).

METHODS

NCM patterns were assessed in 759 consecutive patients with RP. Patterns were classified as normal (n = 354), nonspecific (n = 159), or SSc pattern (n = 246). Abnormal PFT was defined as forced vital or diffusion capacity < 70%. Patients were classified as primary RP (n = 245), or secondary: no definite diagnosis (n = 391), SSc (n = 40), primary Sjögren syndrome (pSS; n = 30), systemic lupus erythematosus (SLE; n = 30), mixed connective tissue disease (MCTD; n = 7), rheumatoid arthritis (RA; n = 15).

RESULTS

An SSc pattern on NCM was frequently observed in most patients with a definite diagnosis: SSc (88%), pSS (33%), SLE (17%), MCTD (71%), and RA (13%). In patients without definite diagnosis, 17% had a normal NCM pattern, 35% nonspecific, and 48% SSc pattern. Abnormal PFT was more frequent in patients with an SSc pattern (35.9% vs 19.5%, p = 0.002), even when corrected for SSc diagnosis (p = 0.003). Absence of an SSc pattern had high negative predictive value (88%); positive predictive values were low.

CONCLUSION

SSc pattern on NCM is common in patients with RP, and in those with connective tissue diseases other than SSc. It is associated with a higher prevalence of abnormal PFT, independent of the presence of an SSc diagnosis. Although these data need validation in a prospective setting, they underline the importance of NCM in RP and putative value to stratify the risk of pulmonary involvement in early stages of disease.

Ultrasound of the Major Salivary Glands is a Reliable Imaging Technique in Patients with Clinically Suspected Primary Sjögren's Syndrome

OBJECTIVE

 To assess the inter- and intraobserver reliability of ultrasound of major salivary glands in patients clinically suspected of having primary Sjögren's syndrome (pSS) as well as to assess sources of variation in outcomes of ultrasonographic evaluation.

METHODS

 80 consecutive outpatients with clinically suspected pSS underwent ultrasound evaluation. The following ultrasound variables of the parotid and submandibular salivary glands were assessed: echogenicity, parenchymal homogeneity, presence of hypoechogenic areas, hyperechogenic reflections and clearness of posterior glandular border, according to the scoring system of Hocevar et al. (total score range: 0 - 48). Images were scored independently by three blinded observers in two sessions.

RESULTS

 The intraobserver reliability of the total ultrasound score was excellent, with an intraclass correlation (ICC) ranging from 0.89 to 0.96. The interobserver reliability was good to excellent, with ICCs of 0.84 and 0.76 for the total ultrasound score in the two sessions. The kappa value ranged from 0.60 to 0.83 depending on the applied cut-offs (cut-off score ≥ 15 and ≥ 17). Hypoechogenic areas and homogeneity of parotid glands showed the highest interobserver reliability. The median kappa for echogenicity was low. The total ultrasound scores varied more between observers in patients with higher ultrasonographic scores (approximately scores ≥ 20).

CONCLUSION

 Ultrasound of major salivary glands is a reliable imaging technique for patients with clinically suspected pSS. Discrepancies between observers in assessing the severity of ultrasound findings may interfere with detecting 'true' changes over time. When monitoring the progression of pSS or treatment efficacy, it is advised that a particular patient be scored by the same ultrasonographer at every time point.

Validation of the ACR-EULAR criteria for primary Sjögren's syndrome in a Dutch prospective diagnostic cohort

Objectives

To validate the ACR-EULAR classification criteria for primary SS (pSS), and compare them to the American-European Consensus Group (AECG) and ACR criteria in a Dutch prospective diagnostic cohort.

Methods

Consecutive patients (n = 129) referred for suspicion of pSS underwent a multidisciplinary evaluation, including a labial and/or parotid gland biopsy. Patients with an incomplete work-up (n = 8) or associated systemic auto-immune disease (n = 7) were excluded. The ACR-EULAR classification was compared with expert classification, AECG and ACR classification. Additionally, the accuracy of individual ACR-EULAR items in discriminating pSS from non-pSS was evaluated. The validity of criteria sets was described separately using parotid or labial gland biopsy results for classification.

Results

Of the 114 evaluated patients, the expert panel classified 34 (30%) as pSS and 80 (70%) as non-pSS. Using labial gland biopsy results, ACR-EULAR classification showed 87% absolute agreement (κ = 0.73) with expert classification, with a sensitivity of 97% and specificity of 83%. Using the parotid gland biopsy results, the ACR-EULAR criteria performed excellently as well. Focus score, anti-SSA titre and ocular staining score showed good to excellent accuracy, whereas unstimulated whole saliva and Schirmer's test had poor accuracy. The ACR-EULAR and AECG criteria had equal validity. Compared with ACR classification, ACR-EULAR classification showed higher sensitivity but lower specificity.

Conclusion

The ACR-EULAR criteria showed good agreement with expert classification, but some patients may be misclassified as pSS. Unstimulated whole saliva and Schirmer's test showed poor discriminative value. The ACR-EULAR criteria performed equally to the AECG criteria, and had higher sensitivity but lower specificity than the ACR criteria.

Scoring hypoechogenic areas in one parotid and one submandibular gland increases feasibility of ultrasound in primary Sjögren's syndrome

OBJECTIVE

To assess whether ultrasonographic scoring of (i) both parotid and submandibular salivary glands and (ii) all individual components of the Hocevar scoring system, is needed for classifying patients as primary Sjögren's syndrome (pSS).

METHODS

Ultrasound examination of the major salivary glands (sUS) was performed in 204 consecutive patients clinically suspected (n=171) or diagnosed (n=33) with pSS.Parenchymal echogenicity, homogeneity, hypoechogenic areas, hyperechogenic reflections and salivary gland posterior border were scored in left and right parotid and submandibular glands. Logistic regression analyses were performed to assess which glands and sUS components contributed significantly to classification as pSS or non-pSS according to the 2016 American College of Rheumatology-European League Against Rheumatism (ACR-EULAR) criteria.

RESULTS

116 (57%) patients were classified as pSS, the remaining as non-pSS. Instead of scoring both sides (area under the curve; AUC=0.856, Nagelkerke R²=0.526), multivariate analysis showed that sUS scoring of only right (AUC=0.850; R²=0.518) or left (AUC=0.852; R²=0.511) parotid and submandibular glands is sufficient to predict ACR-EULAR classification. Moreover, all individual components of the Hocevar scoring system significantly predicted classification. Multivariate analysis showed that parenchymal echogenicity and hypoechogenic areas contributed independently to ACR-EULAR classification (AUC=0.857; R²=0.539). Scoring these components in one parotid and one submandibular gland highly predicted ACR-EULAR classification (AUC=0.855; R²=0.539). Scoring only hypoechogenic areas on one side showed almost similar results (AUC=0.846; R²=0.498).

CONCLUSION

sUS examination of parotid and submandibular glands on one side is sufficient to predict classification of patients according to the ACR-EULAR criteria. To further increase feasibility of sUS in outpatient clinics worldwide, only hypoechogenic areas can be scored.

Ultrasonography of major salivary glands compared with parotid and labial gland biopsy and classification criteria in patients with clinically suspected primary Sjögren's syndrome

OBJECTIVE

To assess the validity of ultrasound of major salivary glands (sUS) compared with parotid and labial gland biopsies, sialometry, anti-SSA/Ro antibody status and classification criteria in patients clinically suspected with primary Sjögren's syndrome (pSS).

METHODS

103 consecutive outpatients with clinically suspected pSS underwent sUS. Parenchymal echogenicity, homogeneity, hypoechogenic areas, hyperechogenic reflections and clearness of salivary gland border were scored according to the Hocevar scoring system. Total ultrasound score was calculated as the sum of these domains (range 0-48).

RESULTS

Absolute agreement between sUS and parotid (83%) and labial (79%) gland biopsy outcome was good. Negative sUS predicts negative parotid gland biopsy, and positive sUS predicts positive labial gland biopsy. Compared with the American European Consensus Group (AECG) classification, sUS showed an absolute agreement of 82%, sensitivity of 71% and specificity of 92%. Compared with the American College of Rheumatology (ACR) classification, absolute agreement was 86%, sensitivity was 77% and specificity was 92%. Compared with the ACR-European League Against Rheumatism (EULAR) classification, absolute agreement was 80%, sensitivity was 67% and specificity was 94%. Positive sUS predicts classification, but negative sUS does not exclude classification. The combination of positive sUS with presence of anti-SSA/Ro antibodies or negative sUS with absence of anti-SSA/Ro antibodies showed a high predictive value for classification as pSS or non-pSS.

CONCLUSION

In our prospective inception cohort study derived from daily clinical practice, absolute agreement between sUS and salivary gland biopsies was slightly higher for parotid compared with labial gland biopsies. The combination of positive sUS and presence of anti-SSA/Ro antibodies highly predicts classification according to the AECG, ACR and ACR-EULAR classification criteria.

Fas Receptor Clustering and Involvement of the Death Receptor Pathway in Rituximab-Mediated Apoptosis with Concomitant Sensitization of Lymphoma B Cells to Fas-Induced Apoptosis

Ab binding to CD20 has been shown to induce apoptosis in B cells. In this study, we demonstrate that rituximab sensitizes lymphoma B cells to Fas-induced apoptosis in a caspase-8-dependent manner. To elucidate the mechanism by which Rituximab affects Fas-mediated cell death, we investigated rituximab-induced signaling and apoptosis pathways. Rituximab-induced apoptosis involved the death receptor pathway and proceeded in a caspase-8-dependent manner. Ectopic overexpression of FLIP (the physiological inhibitor of the death receptor pathway) or application of zIETD-fmk (specific inhibitor of caspase-8, the initiator-caspase of the death receptor pathway) both specifically reduced rituximab-induced apoptosis in Ramos B cells. Blocking the death receptor ligands Fas ligand or TRAIL, using neutralizing Abs, did not inhibit apoptosis, implying that a direct death receptor/ligand interaction is not involved in CD20-mediated cell death. Instead, we hypothesized that rituximab-induced apoptosis involves membrane clustering of Fas molecules that leads to formation of the death-inducing signaling complex (DISC) and downstream activation of the death receptor pathway. Indeed, Fas coimmune precipitation experiments showed that, upon CD20-cross-linking, Fas-associated death domain protein (FADD) and caspase-8 were recruited into the DISC. Additionally, rituximab induced CD20 and Fas translocation to raft-like domains on the cell surface. Further analysis revealed that, upon stimulation with rituximab, Fas, caspase-8, and FADD were found in sucrose-gradient raft fractions together with CD20. In conclusion, in this study, we present evidence for the involvement of the death receptor pathway in rituximab-induced apoptosis of Ramos B cells with concomitant sensitization of these cells to Fas-mediated apoptosis via Fas multimerization and recruitment of caspase-8 and FADD to the DISC.

The role of B cell-mediated T cell costimulation in the efficacy of the T cell retargeting bispecific antibody BIS20x3

In this study, we investigated the role of the naturally occurring B cell-mediated T cell costimulation in the antitumor efficacy of the bispecific Ab BIS20x3. BIS20x3 has a dual specificity for both CD20 and CD3 and has previously been shown to effectively direct the lytic potential of cytolytic T cells toward malignant, CD20(+) B cells. BIS20x3 instigated T cell-B cell interaction caused a dose-dependent activation of T cells that was 30 times stronger when compared with T cell activation induced by monovalent anti-CD3 Abs. The activation of T cells by BIS20x3 and B cells appeared functional and resulted in the rapid induction of high lytic potential in freshly isolated peripheral T cells. BIS20x3-mediated T cell-B cell interaction resulted in a significant up-regulation of ICAM-1 on B cells and the activation of T cells was found to be dependent on the interaction of ICAM-1 with LFA-1 and trans-activation by the NF-kappaB pathway. Also, the lytic potential of freshly isolated T cells activated via BIS20x3 appeared to be dependent on NF-kappaB signaling in the target B cells. Interestingly, the costimulatory signaling effects described in this study appeared specifically related to the targeting against CD20 because targeting against CD19, by a CD3xCD19-directed bispecific Ab, was significantly less effective in inducing T cell activation and T cell-mediated B cell lysis. Together these results demonstrate that the malignant B cells actively contribute to their own demise upon CD20-directed bispecific Ab-mediated T cell targeting.

Low p21Waf1/Cip1 protein level sensitizes testicular germ cell tumor cells to Fas-mediated apoptosis

In the present study, we investigated the relation between p21 expression and the sensitivity of testicular germ cell tumor (TGCT) cells to apoptotic stimuli. Despite similar cisplatin-induced wild-type p53 accumulation, the TGCT cell lines Tera and Scha expressed low p21 protein and mRNA levels in comparison to A2780 ovarian cancer cells. Inhibition of the proteasome complex with MG-132 increased p21 protein levels in TGCT cells but much more in A2780 cells, whereas cisplatin had no additional effect on p21 protein levels. Inhibition of caspase-3 activity in TGCT cells with the broad-spectrum caspase inhibitor zVAD-fmk had no effect on p21 levels and also not upon cisplatin treatment. A similar induction of p53 irradiation, in contrast to cisplatin, substantially increased both p21 mRNA and protein expression in Tera cells. Cisplatin-treated Tera cells expressing low p21 protein levels were Fas-sensitive, while irradiation-induced p21, which was mainly localized in the cytosol, rendered irradiated Tera cells resistant to Fas-induced apoptosis. Sensitivity of irradiated Tera cells to Fas-induced apoptosis was restored by short interfering RNA-specific suppression of p21 expression. These results strongly indicate that the low p21 protein levels are caused by reduced p21 gene transcription and sensitize cisplatin-treated TGCT cells to the Fas death pathway.

Characterization of BIS20x3, a bi-specific antibody activating and retargeting T-cells to CD20-positive B-cells

This paper describes a bi-specific antibody, which was called BIS20x3. It retargets CD3varepsilon-positive cells (T-cells) to CD20-positive cells and was obtained by hybrid-hybridoma fusion. BIS20x3 could be isolated readily from quadroma culture supernatant and retained all the signalling characteristics associated with both of its chains. Cross-linking of BIS20x3 on Ramos cells leads to DNA fragmentation percentages similar to those obtained after Rituximab-cross-linking. Cross-linking of BIS20x3 on T-cells using cross-linking F(ab')2-fragments induced T-cell activation. Indirect cross-linking of T-cell-bound BIS20x3 via Ramos cells hyper-activated the T-cells. Furthermore, it was demonstrated that BIS20x3 effectively re-targets T-cells to B-cells, leading to high B-cell cytotoxicity. The results presented in this paper show that BIS20x3 is fully functional in retargeting T-cells to B-cells and suggest that B-cell lymphomas may represent ideal targets for T-cell retargeting bi-specific antibodies, because the retargeted T-cell is maximally stimulated in the presence of B-cells. Additionally, since B-cells may up-regulate CD95/ Fas expression upon binding of CD20-directed antibodies, B-cells will become even more sensitive for T-cell mediated killing via CD95L/ Fas L, and therefore supports the intention to use T-cell retargeting bi-specific antibodies recognizing CD20 on B-cell malignancies as a treatment modality for these diseases.