Autoantibodies in Autoimmune Pancreatitis

Abstract

Autoimmune pancreatitis (AIP) was first used to describe cases of pancreatitis with narrowing of the pancreatic duct, enlargement of the pancreas, hyper-γ-globulinaemia, and antinuclear antibody (ANA) positivity serologically. The main differential diagnosis, is pancreatic cancer, which can be ruled out through radiological, serological, and histological investigations. The targets of ANA in patients with autoimmune pancreatitis do not appear to be similar to those found in other rheumatological diseases, as dsDNA, SS-A, and SS-B are not frequently recognized by AIP-related ANA. Other disease-specific autoantibodies, such as, antimitochondrial, antineutrophil cytoplasmic antibodies or diabetes-specific autoantibodies are virtually absent. Further studies have focused on the identification of pancreas-specific autoantigens and reported significant reactivity to lactoferrin, carbonic anhydrase, pancreas secretory trypsin inhibitor, amylase-alpha, heat-shock protein, and plasminogen-binding protein. This paper discusses the findings of these investigations and their relevance to the diagnosis, management, and pathogenesis of autoimmune pancreatitis.

Novel Autoantibody Signatures in Sera of Patients with Pancreatic Cancer, Chronic Pancreatitis and Autoimmune Pancreatitis: A Protein Microarray Profiling Approach

“…Microarrays assembled of thousands of different proteins have been already reported and used to identify tumour associated autoantibodies in the context of colorectal cancer [25], bladder cancer [26], ovarian cancer, and pancreatic cancer [8,27]. Furthermore, several studies described elevated autoantibody concentrations in sera of patients with AIP including anti-lactoferrin [28,29], anti-carbonic anhydrase II, anti-carbonic anhydrase IV, anti-pancreas secretory trypsin inhibitor, anti-anionic and cationic trypsinogens, anti-amylase-1, anti-heat shock protein 10 and anti-plasminogen-binding protein peptide autoantibodies [7,18,30]. However, their performance as diagnostic markers is still under debate.…”

“…The ID correctness was confirmed by sequencing the PCR products, from which the relevant proteins were produced recombinantly. Of note, four of these proteins-annexin A4 (ANXA4), protease serine 1 (PRSS1), lactotransferrin (LTF) and peroxiredoxin 4 (PRDX 4)-were already previously reported as AIP autoantigens [7,18]. The normalized median log2 MFI for each candidate for the six compared groups are reported in Table 3.…”

Pancreatic involvement in pediatric inflammatory bowel diseases

“…The role of autoantibodies against the exocrine pancreas, causing direct pancreatic damage with enzyme leakage into the bloodstream, and the histological proof of a granulomatous inflammation of the pancreas has been proposed. [30] Another possible explanation may be linked to abnormal reabsorption of pancreatic amylase/lipase from the gut lumen to the bloodstream because of the increased permeability of the inflamed mucosa. Furthermore, the elevated level of pancreatic enzymes observed in IBD patients may be associated with extrapancreatic lipase/amylase activity in the small bowel and colon; lipase and amylase may be absorbed excessively into the blood in the case of increased …”

Markers for gastrointestinal autoimmune disorders in patients with type 1 diabetes mellitus

“…Сочетание АИП и других аутоиммунных заболеваний предполагает наличие общих антигенов в ПЖ и других органах. Высокая частота встречаемости антител (АТ) к лактоферрину при АИП [7] может свидетельствовать о том, что лактоферрин также может выступать в роли антигена-мишени, вызывая клеточно-опосредованный иммунный ответ при этом заболевании [4,7].…”