Diagnostic accuracy of BP180 NC16a and BP230-C3 ELISA in serum and saliva of patients with bullous pemphigoid

New Frontiers in Autoimmune Diagnostics: A Systematic Review on Saliva Testing

(1) Background: Immunological laboratory testing is known to be complex, and it is usually performed in tertiary referral centers. Many criticalities affect diagnostic immunological testing, such as limited availability, the need for specifically trained laboratory staff, and potential difficulties in collecting blood samples, especially in the most vulnerable patients, i.e., the elderly and children. For this reason, the identification of a new feasible and reliable methodology for autoantibody detection is urgently needed. (2) Methods: We designed a systematic review to investigate the available literature on the utilization of saliva samples for immunological testing. (3) Results: A total of 170 articles were identified. Eighteen studies met the inclusion criteria, accounting for 1059 patients and 671 controls. The saliva collection method was mostly represented by passive drooling (11/18, 61%), and the most frequently described methodology for antibody detection was ELISA (12/18, 67%). The analysis included 392 patients with rheumatoid arthritis, 161 with systemic lupus erythematosus, 131 with type 1 diabetes mellitus, 116 with primary biliary cholangitis, 100 with pemphigus vulgaris, 50 with bullous pemphigoids, 49 with Sjogren syndrome, 39 with celiac disease, 10 with primary antiphospholipid syndromes, 8 with undifferentiated connective tissue disease, 2 with systemic sclerosis, and 1 with autoimmune thyroiditis. The majority of the reviewed studies involved adequate controls, and saliva testing allowed for a clear distinction of patients (10/12 studies, 83%). More than half of the papers showed a correlation between saliva and serum results (10/18, 55%) for autoantibody detection, with varying rates of correlation, sensitivity, and specificity. Interestingly, many papers showed a correlation between saliva antibody results and clinical manifestations. (4) Conclusions: Saliva testing might represent an appealing alternative to serum-based testing for autoantibody detection, considering the correspondence with serum testing results and the correlation with clinical manifestations. Nonetheless, standardization of sample collection processing, maintenance, and detection methodology has yet to be fully addressed.

Bullöses Sweet-Syndrom nach einem Zeckenstich

Wir berichten über einen Patienten, der eine Woche nach einem Zeckenstich Fieber und Papulovesikel entwickelte. Eine disseminierte Borrelien-Infektion sowie eine blasenbildende Erkrankung konnte ausgeschlossen werden. Sowohl klinisch als auch histologisch bestätigte sich ein bullöses Sweet-Syndrom, sodass eine systemische Steroidtherapie begonnen wurde. Darunter besserten sich die Beschwerden des Patienten rasch.

Die Umfelddiagnostik ergab weder Hinweise auf eine hämatologische Erkrankung noch auf eine Medikamenteneinnahme als Auslöser. Dieser Fall deutet darauf hin, dass auch Arthropodenstiche als Trigger für ein Sweet-Syndrom in Betracht gezogen werden können.

Correlation of dermal and blood eosinophilia with bullous pemphigoid disease severity

Background

Bullous pemphigoid (BP) is an autoimmune subepidermal blistering disease associated with immune response against BP-180 and BP-230. Peripheral blood eosinophilia and dermal infiltration of eosinophils are common findings in BP.

Objective

The aim of our study was to demonstrate a statistical correlation between dermal and peripheral blood eosinophilia, anti BP-180, and anti BP-230 IgG and clinical severity of BP.

Methods

A total of 27 patients with newly diagnosed BP were included. Severity of disease was assessed according to the bullous pemphigoid disease activity index (BPDAI). Anti-BP-180 and anti-BP-230 titers, peripheral blood eosinophilia, and dermal eosinophil infiltration and tissue inflammation severity were assessed for each patient.

Results

A significant correlation was found between the serum levels of anti-BP-180 and anti-BP-230, and dermal eosinophilia and tissue inflammation severity with objective and subjective BPDAI scores. In addition, there was a significant correlation between the percentage of peripheral blood eosinophils and subjective BPDAI scores and urticarial/eczematous lesions. Moreover, the mucosal component did not show any correlation with autoantibody levels and inflammation severities.

Conclusion

Anti-BP-180 and anti-BP-230 levels, tissue inflammation severity, and dermal eosinophilia had a strong and significant correlation with BP severity. In addition, percentage of peripheral blood eosinophilia showed a correlation with subjective BPDAI scores.

Advances in the diagnosis of autoimmune bullous dermatoses

Autoimmune bullous dermatoses are defined by autoantibodies directed against adhesion proteins in the epidermis or basement membrane zone, resulting in blister formation on the skin and mucosa. Diagnosis depends on lesional biopsy for histopathology and perilesional biopsy for direct immunofluorescence. Additional diagnostic methods include indirect immunofluorescence, enzyme-linked immunosorbent assay, and immunoblot (Western blot), which may be selected in specific clinical scenarios due to improved sensitivity and/or specificity. This contribution reviews the available evidence supporting the use of each method to provide a practical reference for clinicians when diagnosing autoimmune bullous disorders. Techniques and cost are reviewed, and newer diagnostic techniques with potential for clinical application are.

Protein-Based Salivary Profiles as Novel Biomarkers for Oral Diseases

The Global Burden of Oral Diseases affects 3.5 billion people worldwide, representing the number of people affected by the burden of untreated dental caries, severe periodontal disease, and edentulism. Thus, much more efforts in terms of diagnostics and treatments must be provided in the fight of these outcomes. In this sense, recently, the study of saliva as biological matrix has been identified as a new landmark initiative in the search of novel and useful biomarkers to prevent and diagnose these conditions. Specifically, saliva is a rich reservoir of different proteins and peptides and accessible due to recent advances in molecular biology and specially in targeted and unbiased proteomics technologies. Nonetheless, emerging barriers are an obstacle to the study of the salivary proteome in an effective way. This review aims at giving an overall perspective of salivary biomarkers identified in several oral diseases by means of molecular biology approaches.

Diagnostic value of autoantibody titres in patients with bullous pemphigoid

BACKGROUND

Bullous pemphigoid (BP) is the most common autoimmune blistering disease of the skin requiring skin and serum tests for a precise diagnosis.

OBJECTIVES

We analysed the sensitivity and specificity of BP-relevant parameters and the value of autoantibody titres during follow-up of BP patients.

MATERIALS & METHODS

In a retrospective single-centre study, we included 200 consecutive patients with BP and 400 non-BP patients, and evaluated the test results of patients' serum and skin. In addition, we followed patients' autoantibody titres and clinical characteristics.

RESULTS

BP180-ELISA revealed the highest sensitivity (85.0%; specificity: 93.9%), while BP230-ELISA demonstrated the lowest sensitivity (55.5%; specificity: 92.9%). Direct and indirect immunofluorescence showed comparable results for sensitivity (77.2%/72.7%) and specificity (94.9%/93.7%). The sensitivity for skin histology was 76.3% (specificity: 81.3%). Longitudinal analysis showed significant changes in autoantibody titres.

CONCLUSIONS

BP diagnostics should include serum tests for BP autoantibodies and skin immunofluorescence. Skin histology is supportive for diagnosis. Autoantibody titres are markers for disease activity.

Oral mucosa biology and salivary biomarkers

Although the surfaces of both the skin and oral mucosa are protected by squamous epithelial cells and fall within the scope of dermatologic practice, the oral cavity contains highly specialized structures and functions distinct from other skin biology and pathologic conditions and are also the purview of clinicians who care for patients with skin and mucosal diseases. We describe the distinct features of the tongue, mucosa, and salivary glands. In particular, we examine the composition and function of the saliva, with special focus on salivary biomarkers. Within the oral cavity, saliva shows great promise as a noninvasive and sensitive marker for many systemic diseases. Biomarkers are being used as diagnostic or monitoring tools for a wide variety of diseases, including systemic lupus erythematosus, Sjögren disease, Behçet disease, and autoimmune blistering disorders, as well as premalignant and malignant lesions of the mouth.

Validation of chemiluminescent enzyme immunoassay in detection of autoantibodies in pemphigus and pemphigoid

BACKGROUND

A novel chemiluminescent enzyme immunoassay (CLEIA) was recently developed to quantify autoantibodies specific for desmogleins (Dsgs) and BP180, the target antigens of pemphigus and pemphigoid. This assay is automated and highly accurate and efficient.

OBJECTIVE

To validate the use of the CLEIA for detection of autoantibodies during the clinical courses of patients with pemphigus and pemphigoid.

METHODS

To define cut-off values for Dsg1, Dsg3, and BP180, we evaluated 47 serum samples from patients with pemphigus foliaceus (PF), 59 from those with pemphigus vulgaris (PV), 52 from those with bullous pemphigoid (BP), and 995 from healthy individuals. We also evaluated any fluctuations in CLEIA titers according to disease activity during the clinical course of 10 cases each of PF, PV, and BP. We used clinical symptom scores, the pemphigus disease area index (PDAI) and the bullous pemphigoid disease area index (BPDAI), to evaluate disease activity.

RESULTS

The cut-off values for the CLEIA titers determined by the Youden index were 15.4U/mL for Dsg1, 14.9U/mL for Dsg3, and 16.8U/mL for BP180. CLEIA titers fluctuated in parallel with the PDAI/BPDAI scores in 28 of the 30 cases with PF, PV, or BP. Although the CLEIA and enzyme-linked immunosorbent assay (ELISA) values in the same samples differed substantially in some cases, the concordance rates of positive/negative results between the CLEIA and ELISA were 96% for Dsg1, 97% for Dsg3, and 96% for BP180.

CONCLUSION

The CLEIA, a newly developed, highly effective autoantibody detection system, is as reliable as ELISA for evaluation of the clinical courses of pemphigus and pemphigoid.

Rituximab therapy in pemphigus and other autoantibody-mediated diseases

Rituximab, a monoclonal antibody targeting the B cell marker CD20, was initially approved in 1997 by the United States Food and Drug Administration (FDA) for the treatment of non-Hodgkin lymphoma. Since that time, rituximab has been FDA-approved for rheumatoid arthritis and vasculitides, such as granulomatosis with polyangiitis and microscopic polyangiitis. Additionally, rituximab has been used off-label in the treatment of numerous other autoimmune diseases, with notable success in pemphigus, an autoantibody-mediated skin blistering disease. The efficacy of rituximab therapy in pemphigus has spurred interest in its potential to treat other autoantibody-mediated diseases. This review summarizes the efficacy of rituximab in pemphigus and examines its off-label use in other select autoantibody-mediated diseases.

Detection of inflammatory biomarkers in saliva and urine: Potential in diagnosis, prevention, and treatment for chronic diseases

Inflammation is a part of the complex biological response of inflammatory cells to harmful stimuli, such as pathogens, irritants, or damaged cells. This inflammation has been linked to several chronic diseases including cancer, atherosclerosis, rheumatoid arthritis, and multiple sclerosis. Major biomarkers of inflammation include tumor necrosis factor, interleukins (IL)-1, IL-6, IL-8, chemokines, cyclooxygenase, 5-lipooxygenase, and C-reactive protein, all of which are regulated by the transcription factor nuclear factor-kappaB. Although examining inflammatory biomarkers in blood is a standard practice, its identification in saliva and/or urine is more convenient and non-invasive. In this review, we aim to (1) discuss the detection of these inflammatory biomarkers in urine and saliva; (2) advantages of using salivary and urinary inflammatory biomarkers over blood, while also weighing on the challenges and/or limitations of their use; (3) examine their role(s) in connection with diagnosis, prevention, treatment, and drug development for several chronic diseases with inflammatory consequences, including cancer; and (4) explore the use of innovative salivary and urine based biosensor strategies that may permit the testing of biomarkers quickly, reliably, and cost-effectively, in a decentralized setting.