Interleukin-35 promotes the differentiation of regulatory T cells and suppresses Th2 response in IgG4-related type 1 autoimmune pancreatitis.

BACKGROUND: IgG4-related disease (IgG4-RD) is a systemic inflammatory disease, which includes type 1 autoimmune pancreatitis (AIP). Interleukin-35 (IL-35) exhibits immunosuppressive effects in several autoimmune diseases. However, the expression of IL-35 had not been reported so far in type 1 AIP. We evaluated the association between IL-35 and several cytokines, which mediate the function of Tregs in type 1 AIP. METHODS: Plasma was collected from patients with type 1 AIP, alcoholic chronic pancreatitis (ACP), and healthy controls (HC) and assayed for cytokine expression. Total mRNA separated from peripheral blood was isolated from naïve Tregs (nTregs) and effector Tregs (eTregs). EBI3 and IL-12p35 gene expressions were tested in these cells by quantitative PCR. In addition, expression of IL-35 subunits in the pancreatic tissues of patients with type 1 AIP and ACP was analyzed by immunohistochemistry. RESULTS: IL-35 was significantly elevated in type 1 AIP (n = 32) plasma compared with ACP (n = 16) and HC (n = 22), but IL-27 was not. We also detected many cells expressing both EBI3 and IL-12p35 in type 1 AIP tissues. Moreover, in peripheral blood lymphocyte, the percentage of nTregs and eTregs of CD4+ T cells in patients with type 1 AIP (n = 14) compared with HC (n = 15) was significantly decreased and increased, respectively. There were no significant differences of gene expression in patients with type 1 AIP and HC. CONCLUSIONS: This study identified elevated expression of plasma IL-35 and tissue IL-35 subunits in patients with type 1 AIP. This might lead to inflammation suppression via activated eTregs. IL-35 might be associated with this anti-inflammatory role, especially against the Th2 response through several cytokines and the differentiation of Tregs in type 1 AIP.

Critical Role of TFEB-Mediated Lysosomal Biogenesis in Alcohol-Induced Pancreatitis in Mice and Humans.

BACKGROUND & AIMS: Alcohol abuse is the major cause of experimental and human pancreatitis but the molecular mechanisms remain largely unknown. We investigated the role of transcription factor EB (TFEB), a master regulator of lysosomal biogenesis, in the pathogenesis of alcoholic pancreatitis. METHODS: Using a chronic plus acute alcohol binge (referred to as Gao-binge) mouse model, we analyzed pancreas injury, autophagic flux, zymogen granule removal, TFEB nuclear translocation and lysosomal biogenesis in GFP-LC3 transgenic mice, acinar cell-specific Atg5 knockout (KO) and TFEB KO mice as well as their matched wild type mice. RESULTS: We found that Gao-binge alcohol induced typical features of pancreatitis in mice with increased serum amylase and lipase activities, pancreatic edema, infiltration of inflammatory cells, accumulation of zymogen granules (ZGs) and expression of inflammatory cytokines. While Gao-binge alcohol increased the number of autophagosomes, it also concurrently inhibited TFEB nuclear translocation and TFEB-mediated lysosomal biogenesis resulting in insufficient autophagy. Acinar cell-specific Atg5 KO and acinar cell-specific TFEB KO mice developed severe inflammatory and fibrotic pancreatitis in both Gao-binge alcohol and control diet-fed mice. In contrast, TFEB overexpression inhibited alcohol-induced pancreatic edema, accumulation of zymogen granules and serum amylase and lipase activities. In line with our findings in mice, decreased LAMP1 and TFEB nuclear staining were also observed in human alcoholic pancreatitis tissues. CONCLUSIONS: our results indicate that TFEB plays a critical role in maintaining pancreatic acinar cell homeostasis. Impairment of TFEB-mediated lysosomal biogenesis by alcohol may lead to insufficient autophagy and promote alcohol-induced pancreatitis.

Human Antigen Leucocyte (HLA)-G and HLA-E are differentially expressed in pancreatic disorders.

BACKGROUND: Little information is available regarding the expression of the immunomodulatory Human Leukocyte Antigen (HLA)-G and -E molecules in pancreatic disorders. AIM: To analyze HLA-G and -E expression in specimens of alcoholic chronic pancreatitis (ACP), idiopathic chronic pancreatitis (ICP), type 1 (T1D) and type 2 diabetes (T2D) and in histologically normal pancreas (HNP). METHODS: HLA-G and -E expression (ACP = 30, ICP = 10, T1D = 10, T2D = 30 and HNP = 20) was evaluated by immunohistochemistry in three different areas (acini, islets and inflammatory infiltrate). RESULTS: Acini and islets from HNP specimens exhibited higher HLA-G and -E expression compared to corresponding areas from all other patient groups. In inflammatory infiltrate, HLA-G and -E expression was observed only among the pancreatic disorders. We observed higher HLA-G and -E expression in acini from T2D compared to ACP, as well as higher HLA-G expression compared to ICP. CONCLUSION: The decreased expression of HLA-G and -E in islets and acini together with the expression of these molecules in the inflammatory infiltrating cells were shared features among chronic inflammatory and autoimmune pancreatic disorders evaluated in this study, possibly reflecting tissue damage.

Alcohol's Effect on Host Defense.

Alcohol affects many organs, including the immune system, with even moderate amounts of alcohol influencing immune responses. Although alcohol can alter the actions of all cell populations involved in the innate and adaptive immune responses, the effect in many cases is a subclinical immunosuppression that becomes clinically relevant only after a secondary insult (e.g., bacterial or viral infection or other tissue damage). Alcohol's specific effects on the innate immune system depend on the pattern of alcohol exposure, with acute alcohol inhibiting and chronic alcohol accelerating inflammatory responses. The proinflammatory effects of chronic alcohol play a major role in the pathogenesis of alcoholic liver disease and pancreatitis, but also affect numerous other organs and tissues. In addition to promoting proinflammatory immune responses, alcohol also impairs anti-inflammatory cytokines. Chronic alcohol exposure also interferes with the normal functioning of all aspects of the adaptive immune response, including both cell-mediated and humoral responses. All of these effects enhance the susceptibility of chronic alcoholics to viral and bacterial infections and to sterile inflammation.

Comparison of neutrophil infiltration between type 1 and type 2 autoimmune pancreatitis.

BACKGROUND: Characteristics of type 2 autoimmune pancreatitis (AIP) is granulocyte epithelial lesions, called idiopathic duct-centric pancreatitis (IDCP). To clarify pathogenesis of IDCP, we investigated mechanism of neutrophil infiltration in type 1 AIP, called lymphoplasmacytic sclerosing pancreatitis (LPSP) and IDCP. METHOD: This study was performed on resected pancreata from patients with alcoholic chronic pancreatitis (ACP, n = 10), LPSP (n = 10) and IDCP (n = 12). The number of neutrophils around the pancreatic ducts was counted. The expression of neutrophils chemoattractants granulocyte chemotactic protein-2 (GCP-2) and interleukin-8 (IL-8) in the pancreatic duct epithelia was examined using immunohistochemistry. The cell staining intensity is scored as negative (0), weak (1), moderate (2) or strong (3). RESULTS: The median number of neutrophils around the interlobular pancreatic ducts was significantly higher in IDCP (15.16; interquartile range [IQR]: 9.74-18.41) than in ACP (2.66; IQR: 1.33-4.33) (P < 0.05) and LPSP (3.16; IQR: 2.74-4.57) (P < 0.01). There was no significant difference in the median number of neutrophils around the intralobular pancreatic ducts among ACP (1.16; IQR: 0.33-3.41), LPSP (3.16; IQR: 0.74-5.5) and IDCP (3.00; IQR: 1.08-7.91). The median score of GCP-2 in the interlobular pancreatic duct epithelia was significantly higher in IDCP (1.5; IQR: 0.25-2) than in ACP (0; IQR: 0-0.75) (P < 0.05) and LPSP (0; IQR: 0-0.75) (P < 0.05). There was no significant difference in the median score of IL-8 in the interlobular pancreatic duct epithelia among ACP (0; IQR: 0-0.75), LPSP (1; IQR: 0-1.75) and IDCP (0.5; IQR: 0-1). CONCLUSIONS: Significantly increased neutrophil infiltration around the interlobular pancreatic duct in IDCP may depend on GCP-2.

Possible involvement of Toll-like receptor 7 in the development of type 1 autoimmune pancreatitis.

BACKGROUND: High serum immunoglobulin G4 (IgG4) levels and IgG4-positive plasma cell infiltration are characteristic of type 1 autoimmune pancreatitis (AIP). It is unclear whether innate immunity is a cause of type 1 AIP; the possible involvement of microbial infection has been suggested in its pathogenesis. To clarify the pathogenesis of type 1 AIP, we investigated Toll-like receptors (TLRs) in type 1 AIP patients. METHODS: We studied nine cases of type 1 AIP with ten cases of alcoholic chronic pancreatitis (ACP) and three of the samples from non-tumorous lesion of neuroendocrine tumor (NET) as control subjects. We counted the number of TLR1-11-positive cells immunohistochemically stained with anti-TLR1-11 antibodies. To identify TLR-positive cells in pancreata from type 1 AIP patients, we used a double-immunofluorescence method and counted the numbers of identifiable CD68-, CD163-, CD123-, and CD20-positive cells. RESULTS: In type 1 AIP, TLR7 (8.815 ± 1.755), TLR8 (3.852 ± 1.489), and TLR10 (3.852 ± 0.921) were highly expressed. Only the ratio of TLR7 per monocyte was significantly higher in type 1 AIP (0.053 ± 0.012) than in ACP (0.007 ± 0.004; p < 0.01) and non-tumorous lesion of NET (0.000 ± 0.000; p < 0.01). In type 1 AIP, the CD163 to TLR7 ratio (0.789 ± 0.031) was significantly higher both than that of CD123 to TLR7 ratio (0.034 ± 0.006; p < 0.001) and CD20 to TLR7 ratio (0.029 ± 0.010; p < 0.001). CONCLUSIONS: TLR7 might be key pattern-recognition receptors involved in the development of type 1 AIP.

Regulation of pancreatic inflammation by connective tissue growth factor (CTGF/CCN2).

Pancreatitis is caused by long-term heavy alcohol consumption, which results in injury and death of pancreatic acinar cells (PAC). The PAC play a pivotal role in mediating early inflammatory responses but the underlying mechanisms remain poorly understood. Treatment of C57BL/6 mice with ethanol and cerulein resulted in increased staining for acinar interleukin- 1b (IL-1b), chemokine (C-C motif) ligand 3 (CCL3), or connective tissue growth factor (CTGF/CCN2) by Day 16 and this was associated with increased infiltration of F4/80-positive macrophages and increased expression of pancreatic CTGF/CCN2 mRNA. Compared with wild-type Swiss Webster mice, ethanol treatment of pan-green fluorescent protein (GFP)-CTGF/CCN2 transgenic mice caused enhanced acinar staining for GFP or CTGF/CCN2 and a significant increase in pancreatic infiltration of F4/80-positive macrophages or NIMP-R14-positive neutrophils. Treatment of primary mouse PAC or the rat AR42J PAC line with ethanol or CTGF/CCN2 resulted in enhanced expression of IL-1b or CCL3. Conditioned medium from CTGF/CCN2-treated AR42J cells induced chemotaxis in NR8383 macrophages and this response was abrogated in a dose dependent manner by addition of BX471, an inhibitor of chemokine (C-C motif) receptor 1. These results reveal that acinar CTGF/CCN2 plays a novel role in alcohol-induced inflammatory processes in the pancreas by increasing infiltration of macrophages and neutrophils and increasing acinar production of inflammatory mediators such as IL-1b or CCL3. The early production of CTGF/CCN2 by PAC to drive inflammation is distinct from its previously reported production by pancreatic stellate cells to drive fibrosis at later stages of pancreatic injury.

Low plasma antibodies specific for phosphatidylethanol in alcohol abusers and patients with alcoholic pancreatitis.

Phosphatidylethanol (PEth) is a group of alcohol-modified phospholipids present in cell membranes after heavy drinking. Our aim was to demonstrate the presence of human plasma antibodies binding to PEth and to address their specificity and value in detecting subjects engaged in heavy alcohol consumption. Antibodies to PEth were analyzed in plasma from heavy drinkers (n=20), patients with alcoholic pancreatitis (n=58) and control subjects (n=24), using chemiluminescent immunoassay. Heavy drinkers and patients with alcoholic pancreatitis demonstrated significantly lower levels of plasma IgG, IgA and IgM titers to PEth compared with controls (P<0.001). The specificity of the antibodies to PEth was demonstrated with competitive liquid phase immunoassays and flow cytometry. The plasma IgG, but not IgA or IgM, titers to PEth in heavy drinkers correlated with the whole blood PEth concentration determined by liquid chromatography-mass spectrometry (r=0.655, P=0.002). Compared with traditional markers for alcohol abuse (aspartate aminotransferase, gamma-glutamyl transpeptidase and mean corpuscular volume), receiver operating characteristic curve analysis showed that a low plasma IgA to PEth had the highest area under the curve (AUC 0.940, P<0.001). In conclusion, plasma IgG, IgA and IgM antibodies binding specifically to PEth were found in subjects of all study groups. Subjects with heavy alcohol consumption showed markedly lower plasma immunoglobulin levels to PEth, potentially making them useful as a biomarker to distinguish heavy from moderate alcohol use.

Mannan-binding lectin and mannan-binding lectin-associated serine protease 2 in acute pancreatitis.

OBJECTIVES: Complement activation may play a prominent role in acute pancreatitis (AP). Mannan-binding lectin (MBL) and MBL-associated serine protease 2 (MASP-2) participate in complement activation. The objective of the present study was to evaluate the role of MBL and MASP-2 as markers in AP with regard to etiology, inflammatory activity, severity, and development of multiorgan failure. METHODS: Sixty patients with AP were included. All patients were diagnosed and treated according to a standardized regimen. Blood samples were obtained immediately on admission and again on days 1, 2, and 14. RESULTS: Both MBL (P < 0.001) and MASP-2 (P = 0.002) levels changed significantly over time, but without any significant relation to severity, multiorgan failure, or mortality. We found significantly higher levels of MBL (P = 0.04) in alcohol- than in gallstone-induced AP, but no significant difference in MASP-2 levels. CONCLUSIONS: The MBL and MASP-2 acted as acute-phase reactants, but overall, they were not markers for severity, multiorgan failure, nor for mortality in AP. Our results suggest that MBL and MASP-2 play only a minor role in the inflammatory response in AP.

Deposition of complement C3c, immunoglobulin (Ig)G4 and IgG at the basement membrane of pancreatic ducts and acini in autoimmune pancreatitis.

AIMS: Autoimmune pancreatitis (AIP) is a type of pancreatitis whose immunopathogenesis is still unknown. It has been reported that renal biopsy specimens from patients diagnosed with both AIP and tubulointerstitial nephritis reveal deposits containing complement C3, immunoglobulin (Ig)G and IgG4 at the tubular basement membranes (BMs). The aim was to investigate the deposition of complement and immunoglobulins in pancreatic tissue from AIP patients compared to non-AIP patients. METHODS: Double immunofluorescence microscopy for C3c, IgG4 and IgG together with CK7, trypsin, collagen IV, CD31 and CD79a, as well as immunofluorescence microscopy for C1q, IgA and IgM, were performed on frozen pancreatic tissue from AIP and alcoholic chronic pancreatitis (ACP) patients. RESULTS: In AIP patients, complement C3c, IgG4 and IgG were deposited at the collagen IV-positive BMs of pancreatic and bile ducts and of acini. In a minority of the ACP patients, weak C3c-positive BM deposits were detected, but no IgG4- or IgG-positive BM deposits were present. CONCLUSION: The deposition of C3c, IgG4 and IgG at the BM of small- and medium-sized ducts and acini of the pancreas is characteristic of AIP. This suggests that immune complex-mediated destruction of ducts and acini play a role in the pathogenesis of AIP.

Inflammation and pancreatic cancer: an evidence-based review.

There is a growing awareness that inflammation plays a contributory role in numerous pathologies, including pancreatic carcinogenesis. Inflammatory states are characterized by the creation of reactive oxygen species and the induction of cell cycling for tissue growth and repair. The initiation, promotion and expansion of tumors may be influenced by numerous components that function in the inflammatory response. Recognized risk factors for pancreatic cancer include cigarette smoking, chronic/hereditary pancreatitis, obesity and type II diabetes. Each risk factor is linked by the fact that the inflammatory state significantly drives its pathology. This article will outline how inflammatory mechanisms are etiologically linked to pancreatic adenocarcinoma.

Proinflammatory cytokines in alcohol or gallstone induced acute pancreatitis. A prospective study.

OBJECTIVES: If differences of inflammatory pathways in acute pancreatitis exist for various etiologies, selective and specific antiinflammatory and other modulatory treatment regimens might be indicated. Circulating levels of prominent proinflammatory cytokines IL-6, 8, 18, and TNF-alpha were measured in patients having their first attack of either alcohol- or gallstone-induced acute pancreatitis. METHODS: Seventy-five consecutive patients were prospectively included over a 15-month period, sixty of them being either alcohol- or gallstone-induced. All patients were treated according to a standardized algorithm. Blood samples were obtained immediately on admission and, again, at days 1, 2, and 14. RESULTS: A significant effect of the etiology on the levels of IL-8 in the alcohol group as compared to the gallstone group (P=0.003) was found. No etiologic differences were observed for IL-6, IL-18, TNF-alpha, or CRP. Furthermore, no significant differences, either regarding the need for treatment at the intensive care unit or of 30-day mortality, were found. CONCLUSION: The present study confirms previous findings and supports the hypothesis that, except for IL-8, the biochemical profile and clinical outcome is independent of the underlying etiology. Revealing the complex spatial and temporal profile of proinflammatory cytokine expression in acute pancreatitis is necessary and important for the development of a more targeted rational therapy.

Fractalkine and TGF-beta1 levels reflect the severity of chronic pancreatitis in humans.

AIM: To clarify whether serum chemokine and cytokine levels can become useful biological and functional markers to assess the severity of chronic pancreatitis (CP). This study aimed at clarifying whether serum chemokine and cytokine levels can become useful biological and functional markers to assess the severity of CP. METHODS: Serum monocyte chemoattractant protein-1 (MCP-1), transforming growth factor beta-1 (TGF-beta1), and soluble type fractalkine (s-fractalkine) concentrations were examined in patients with CP (n = 109) and healthy controls (n = 116). Severity of disease was classified in patients with CP by a staging system. Relationships between stage-specific various clinical factors and serum MCP-1, TGF-beta1, and s-fractalkine levels were investigated. Furthermore, 57 patients with non-alcoholic CP were similarly evaluated in order to exclude influence of alcohol intake. RESULTS: Patients with CP showed significant higher levels of serum TGF-beta1 and s-fractalkine, but not MCP-1, compared to the controls. Serum TGF-beta1 in the severe stage and s-fractalkine in the mild and the severe stage of CP significantly increased compared to those of controls. However, it was observed that both TGF-beta1 and s-fractalkine levels were affected by alcohol intake. In patients with non-alcoholic CP, serum TGF-beta1 showed significant increase in the moderate stage of CP, and serum s-fractalkine revealed significant increase in the early stage of CP. CONCLUSION: It is suggested that the measurement of serum F-fractalkine is useful to diagnose early-stage CP. Moreover, the combined determination of both, s-fractalkine and TGF-beta1, in human sera may be helpful in evaluating the severity status of CP.

Potential for differential diagnosis of autoimmune pancreatitis and pancreatic cancer using carbonic anhydrase II antibody.

OBJECTIVES: Pancreatic ductal epithelia contain an abundance of carbonic anhydrase (CA), and the presence of antibodies to this enzyme has been described in autoimmune disorders. We previously found a small amount of an immunoglobulin G-like material in purchased CAII reagents, which led to pseudopositive reactions. METHODS: We determined the optimum measurement conditions for detecting anti-CAII antibody using an enzyme-linked immunosorbent assay and sera from 140 patients with pancreatic diseases. RESULTS: Compared with the prevalence of anti-CAII antibody in healthy subjects, a significantly higher seroprevalence of the antibody was detected in patients with autoimmune pancreatitis (AIP) (88.9%, P < 0.02), Sjögren syndrome (67.6%, P < 0.01), and alcoholic chronic pancreatitis (45.8%, P < 0.01). No positive results were obtained among patients with pancreatic cancer. Moreover, the antibody value obtained in the pancreatic cancer patients was actually lower than that obtained in healthy subjects. CONCLUSIONS: The anti-CAII antibody is probably not a specific marker of AIP because it was present at a higher frequency in the sera of patients with other pancreatic diseases. Nevertheless, the anti-CAII antibody may be a useful tool for the differential diagnosis of AIP and pancreatic cancer.

Polymorphisms of the TNF, CD14, and HSPA1B genes in patients with acute alcohol-induced pancreatitis.

OBJECTIVES: Genotype assessment has been suggested to be a tool for predicting disease severity in acute pancreatitis (AP). To study this hypothesis, we performed genotype analysis of tumor necrosis factor (TNF) -308 A/G, CD14 -159C/T, and HSPA1B +1267 A/G polymorphisms. METHODS: This is a case-control association study of 397 patients with AP (214 of whom had an alcohol-induced AP) and 300 controls. The control group comprised 218 subjects with detailed data of alcohol consumption, 70 of whom were heavy drinkers (daily alcohol intake >40 g), and 92 blood donors. The severity of AP was determined according to the Atlanta classification. Genotyping was performed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry-assisted genotyping method. RESULTS: Major allele frequency in TNF gene was 0.87 for patients with AP and 0.86 for controls. For CD14, the gene major allele frequency was 0.60 for patients and 0.63 for controls. For HSPA1B, the major allele frequencies were 0.52 for patients and 0.49 for controls, respectively. The allele frequencies did not differ significantly between AP patients with organ failure and those with mild disease, patients with alcohol-induced AP, or those with biliary AP. The patients with septic infectious complications (n = 47) had genotype distribution no different from those with mild, uncomplicated disease (n = 245). CONCLUSIONS: The TNF, CD14, and HSPA1B polymorphisms studied seem not to play a role in determining the severity of AP or the risk of alcohol-induced AP and thus do not serve as a tool for predicting disease severity.

Clinical significance of swollen duodenal papilla in autoimmune pancreatitis.

OBJECTIVES: To evaluate the clinical significance of a swollen main duodenal papilla and the associated immunohistopathologic findings in patients with autoimmune pancreatitis (AIP). METHODS: Seventeen consecutive patients with AIP registered between April 2001 and October 2005 who underwent both endoscopic retrograde cholangiopancreatography and endoscopic biopsy were enrolled in this study. The endoscopic features, stromal inflammatory cell infiltrate (SICI), and results of immunohistochemical examination of the duodenal papilla using IgG4, CD3, and CD79a antibodies were retrospectively reviewed. These findings in the AIP patients were compared with those in 12 patients with chronic alcoholic tumor-forming pancreatitis (CAP). The numbers of cells in the SICI and of IgG4-positive plasma cells per high-power field were counted in all the histopathologic specimens. RESULTS: A swollen main duodenal papilla was observed in 11 (11 [64.7%]/17) patients with AIP and 4 (4 [33.3%]/12) patients with CAP (P < 0.05). Resolution of the swollen main duodenal papilla was observed in all of these 11 patients with AIP (11 [100%]/11) in response to treatment with corticosteroids. On the other hand, the 6 patients without elevated serum IgG4 or a swollen duodenal papilla, but with a swollen pancreas, improved even without corticosteroid treatment. The number of cells in the SICI in the AIP patients was significantly higher than that in the CAP patients. Although in 13 of 17 AIP patients, infiltration by IgG4-positive plasma cells was detected in the duodenal papilla, no such significant infiltration of the duodenal papilla by IgG4-positive plasma cells was observed in the patients with CAP (P < 0.05). More predominant T-cell infiltration of the duodenal papilla was recognized in the AIP patients than in the CAP patients (P < 0.05). CONCLUSIONS: These results suggest that a swollen main duodenal papilla with IgG4-positive plasma cell and T-cell-dominant infiltration and an abundant stromal cell infiltrate are characteristic findings in AIP. We suggest that these findings may be valuable adjuncts to the diagnosis of AIP as well as for selecting suitable candidates for corticosteroid therapy.

Immune-compromised state in the rat pancreas after chronic alcohol exposure: the role of peroxisome proliferator-activated receptor gamma.

Alcohol exposure is known to sensitize acinar cells to various insults but the pathophysiological mechanisms of alcoholic pancreatitis remain unknown. Alcohol abuse has been shown to mediate an anti-inflammatory response and periods of immune suppression seem to be associated with organ injury and mortality. The purpose of this study was to determine the mechanisms by which alcohol exerts transcriptional activities in the rat pancreas and how alcohol alters the inflammatory response. Using the Lieber-DeCarli alcohol/control diet, rats that were fed with alcohol over 14 weeks demonstrated a decrease of inflammatory cells in pancreatic tissue compared to controls. The anti-inflammatory effects of alcohol were confirmed by decreased expression of pro-inflammatory cytokines including TNFalpha, IL-1beta, IL-18, TGFbeta, and MCP-1. In addition, alcohol significantly increased the activity of PPARgamma, which is a known anti-inflammatory transcription factor, while pro-inflammatory factors including AP-2 and EGR-1 were significantly suppressed. NFkappaB binding showed a tendency towards a reduction. Electron microscopy studies revealed enlarged and injured mitochondria and lysosomes, accompanied by peri-cellular fibrosis. Furthermore, alcohol exposure increased the activities of trypsin and cathepsin B, both known to be critical in initiating acinar cell injury and pancreatitis. Despite the known alcohol-mediated acinar cell and mitochondrial injury, the mitochondrial-mediated apoptotic pathway was attenuated. These data demonstrate that the pancreas exposed to alcohol maintains an anti-inflammatory state by activating PPARgamma. Intracellular mitochondrial and lysosomal damage after chronic alcohol exposure induces premature activation of digestive enzymes and establishment of peri-cellular fibrosis in the absence of inflammation.

Effect of ethanol on inflammatory responses. Implications for pancreatitis.

BACKGROUND/AIMS: Alcohol use alters inflammatory cell responses. While alcohol has direct effects on pancreatic acinar cells, activation of inflammatory cells is a major component of the pathology of alcoholic pancreatitis. METHODS: The effects of acute or chronic alcohol exposure were evaluated in human monocytes on the production of TNFalpha or IL-10 production, pro-inflammatory gene and nuclear factor-kappaB (NF-kappaB) activation. RESULTS: Moderate, acute alcohol consumption or equivalent doses of alcohol in vitro had anti-inflammatory effects on monocyte activation via inhibition of pro-inflammatory genes and NF-kappaB activation, inhibition of TNFalpha production and augmentation of the anti-inflammatory cytokine, IL-10. In contrast, acute alcohol treatment augmented NF-kappaB activation and TNFalpha production and inhibited IL-10 levels in the presence of complex stimulation with combined TLR2 and TLR4 ligands. Prolonged alcohol exposure also resulted in an increase in NF-kappaB and TNFalpha production in response to TLR4 stimulation with LPS. CONCLUSION: These results suggest that alcohol can either attenuate or promote inflammatory responses that are critical in pancreatitis. Our results support the hypothesis that both acute alcohol intake in the presence of complex stimuli (such as necrotic cells) and chronic alcohol exposure result in hyper-responsiveness of monocytes to inflammatory signals and may contribute to increased inflammation in pancreatitis.

IgG4-positive plasma cell infiltration in the diagnosis of autoimmune pancreatitis.

Autoimmune pancreatitis typically produces an enlarged pancreas with narrowing of the pancreatic duct, and can mimic carcinoma. Autoimmune pancreatitis usually responds to corticosteroid treatment, making it important to differentiate from pancreatic ductal adenocarcinoma. Affected patients often have an elevated serum IgG4. It has been proposed that increased numbers of IgG4-positive plasma cells in tissue might be a marker for the condition. We investigated the role of IgG4 staining in the diagnosis of autoimmune pancreatitis, first in resected pancreas specimens (29 autoimmune pancreatitis, nine chronic alcoholic pancreatitis and 25 pancreatic cancer), then in pancreatic needle biopsies. Immunohistochemical stains for IgG4 were scored as none, mild, moderate or marked, according to published criteria. Moderate to marked numbers of IgG4-positive plasma cells were seen in 21/29 autoimmune pancreatitis patients, and were distributed in and around ducts, in interlobular fibrous tissue and in peripancreatic fat. In contrast, eight of nine examples of chronic alcoholic pancreatitis and 22/25 ductal adenocarcinomas had scores of none or mild. When we subdivided autoimmune pancreatitis into the histologic subtypes lymphoplasmacytic sclerosing pancreatitis and idiopathic duct-destructive pancreatitis, 16/17 lymphoplasmacytic sclerosing pancreatitis had moderate to marked staining, compared to five to 12 idiopathic duct-destructive pancreatitis. Needle biopsies from nine patients suspected of having autoimmune pancreatitis had increased numbers of IgG4 cells. We conclude that pancreatic tissue from patients with autoimmune pancreatitis often shows moderate or marked infiltration by IgG4-positive plasma cells (>10/HPF). This is particularly so in the subtype we have designated lymphoplasmacytic sclerosing pancreatitis. We rarely see IgG4 staining in patients with chronic alcoholic pancreatitis and pancreatic ductal adenocarcinoma. IgG4-positive plasma cells are a useful marker for the tissue diagnosis of autoimmune pancreatitis.