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:

Continue reading

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

Heart Disease Risk in RA: Obviously, Common Assessment Tools are Insufficient


In rheumatoid arthritis, standard heart disease risk tools underrate danger!

Patients suffering from rheumatoid arthritis, or RA for short, are at higher risk for heart disease. Among experts that’s a matter of common knowledge (fortunately and increasingly that is basic knowledge among patients, too!).

Warenign sign. Elderly people crossing.

Watch out, doctors! – In elderly rheumatoid arthritis patients commonly used heart disease risk assessment tools regularly fail, according to a current study. – © Robbie Ribeiro

On a less positive note, commonly used heart disease risk assessment tools seem to be inadequate for estimating the risk of cardiovascular disease danger faced by RA patients. That is what a brand-new study found.

In this blog article I summarise the main results of the research done at Mayo Clinic in Rochester, Minnesota (USA). The study is entitled Usefulness of Risk Scores to Estimate the Risk of Cardiovascular Disease in Patients With Rheumatoid Arthritis, and it has been published online on 20th April 2012 in The American Journal of Cardiology.

Heart disease risk in RA: More accurate assessment tools needed

The study estimated the accuracy of the Framingham and Reynolds risk scores, two tools commonly used by physicians for assessing patients’ heart disease danger. The scientists found that these two assessment tools substantially underrated cardiovascular disease danger both in women and men suffering from rheumatoid arthritis. In particular, that happens in older patients. Interestingly enough, it also happens in people who test positive for rheumatoid factors. Continue reading