Portrait of the HEp2 cell, the pet of immunofluorescence professionals


HEp2 cells -- centromere B

Anti-Centromere B on HEp2 cells

HEp2 cells are held dear in autoimmune diagnostics. They are invaluable for people engaged in analysing autoantibodies, as E. coli is for molecular biologists or mice for toxicologists.

In spite of a wide range of other suitable methods and technologies, determination of autoantibodies with indirect immuno-fluorescence assays (IFA) on human epithelioma (HEp2) cells still contributes significantly to the diagnosis of autoimmune diseases. The widely recognised advantages of this method are high sensitivity and a broad spectrum of antibodies that can be analysed simultaneously. In addition to mere detection of antibodies a characteristic fluorescence pattern and staining of metaphase and cytoplasmic cells offer supplementary information.

When an autoimmune disease is suspected, the HEp-2 test usually is the first line test. Any positive result is then followed up by a step-wise diagnostic approach, including other immunological tests like ELISA (enzyme-linked immunosorbent assay) for single antibody specificities or immunoblot tests. Continue reading

Immunofluorescence Tests in Crescentic Glomerulonephritis


The web community GRÜNER CLUB AUTOIMMUN is a voluntary association of scientists, laboratory specialists, medical doctors, students and immunofluorescence enthusiasts from Austria. In their internet blog these experienced IFT professionals  discuss questions, ideas and concepts of immunofluorescence tests in autoimmune disease diagnostics.

DER GRÜNE CLUB AUTOIMMUN

In a recent posting my Austrian colleague Barbara Fabian, community manager of GRÜNER CLUB AUTOIMMUN, refered to the relationship  between the formation of  autoantibodies against glomerular basal membrane (GBM) and ANCA (antibodies against cytoplasmic antigens of neutrophil granulocytes). The article was originally written in German language, but we had it translated  for the not German speaking readers of the Autoimmunity Blog.

Autoantibodies against Glomerular Basal Membrane and Myeloperoxidase in Crescentic Glomerulonephritis

by Barbara Fabian, Vienna

Crescentic Glomerulonephritis (CGN) is an autoimmune disease of the kidney that leads to vasculitis of the capillaries in the glomeruli. The appearance of characteristic autoantibodies or antibody complexes is indicative of CGN and allows for the differentiation of three groups:

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Research Update: Osteoimmunology


Linking autoantibody production to bone loss

in rheumatoid arthritis

Inflammation of the synovium in a joint affected by rheumatoid arthritis

Autoantibodies against citrullinated proteins (ACPA) are found in people with rheumatoid arthritis and are one of the strongest risk factors for bone destruction in this disease. A recent study now directly links the formation of antibodies binding to mutated citrullinated vimentin (anti-MCV) to bone loss in rheumatoid arthritis, indicating that these autoantibodies act on osteoclasts, the bone cells responsible for bone resorption.

Harre U, Georgess D, Bang H, Bozec A, Axmann R, Ossipova E et al. Induction of osteoclastogenesis and bone loss by human autoantibodies against citrullinated vimentin. J Clin Invest 2012; 122(5):1791-802. (1)                    

The research of  U. Harre, G. Schett and their coworkers provides fundamental new insights into the interaction between bone and the immune system in the inflammatory process leading to the development of rheumatoid arthritis.

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Research Update: New Classification Criteria for Sjoegren’s Syndrome


Since the early 1960s almost a dozen different criteria for Sjögren’s syndrome (SS) have been published, both for classifying and for diagnosing that autoimmune disease. Recently, an international team of rheumatologists has published new classification criteria for Sjögren’s syndrome. In the April issue of the Arthritis Care & Research journal the authors propose clear and carefully worded guidelines.

Without question, these “new 2012 classification criteria for Sjögren’s syndrome” are urgently needed to better support etiologic and genetic research and therapeutic trials for Sjögren’s syndrome. Indeed, the new criteria are the first to be based solely on objective clinical tests!

Many other criterions have permitted various testing subjectivity to enable the classification of the disorder. In consequence, subjectivity has made standardisation of clinical trial inclusion something of a moving target, limiting comparability of research data across studies and impeding the needed robust clinical evaluation of possible new treatments. But criteria used for enrollment into clinical trials need to be clear, be easy to apply. And the new 2012 criteria agree to that demand. Continue reading

New Guidelines for the Diagnosis of Celiac Disease


Celiac disease diagnostics revised 

Anti-endomysial antibodies on monkey esophagus

Anti-endomysial antibodies on monkey esophagus

The diagnostic criteria for celiac disease (CD) have remained unchanged for more than 20 years, after the 1990 revision of the guidelines originally formulated in 1969.  During this period the disease has been intensively studied and scientific findings have unveiled the genetic background of celiac disease, linked to the human leukocyte antigen (HLA)-DQ2 and HLA-DQ8 haplotypes. The key autoantigen tissue transglutaminase (tTG) has been identified and reliable laboratory tests for disease specific autoantibodies now contribute to diagnostics and complement the methodological repertoire of clinical observations and histologic findings in duodenal biopsy samples. Finally, the European Society for Paediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN) has now published New Guidelines for the Diagnosis of Celiac Disease.

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