bromochloroacetic-acid and Pancreatitis

Type 1 autoimmune pancreatitis (AIP) is histologically characterized by dense lymphoplasmacytic infiltration and marked storiform fibrosis, manifestations associated with pancreatic ducts. Such periductal lymphocyte recruitment is thought to be elicited by dysregulation of mechanisms governing physiological lymphocyte homing. The present study was undertaken to determine whether vascular addressins including peripheral lymph node addressin and mucosal addressin cell adhesion molecule 1 (MAdCAM-1) play a role in type 1 AIP histogenesis.. Tissue sections of type 1 AIP and tumor-associated non-AIP chronic pancreatitis, as well as normal pancreas, were subjected to immunohistochemical analysis using vascular addressin-related antibodies.. The number of periductal mouse endothelial cell antigen 79-positive high endothelial venule (HEV)-like vessels was increased in type 1 AIP relative to that seen in non-AIP chronic pancreatitis, whereas the number of MAdCAM-1-positive HEV-like vessels did not differ between the 2 conditions. Mouse endothelial cell antigen 79 antigens are expressed on duct-forming epithelial cells not only in pancreas but also in salivary glands, which often harbor extrapancreatic lesions in type 1 AIP.. Type 1 AIP can be characterized by periductal induction of MECA-79-positive HEV-like vessels. MECA-79-positive 6-sulfo sialyl Lewis X-related carbohydrate antigens expressed on duct-forming epithelial cells could be associated with type 1 AIP pathogenesis.

Topics: Antigens, CD34; Antigens, Surface; Autoimmune Diseases; Biomarkers; Cell Adhesion Molecules; Humans; Immunoglobulin G; Immunoglobulins; Immunohistochemistry; Keratins; Lymphatic Vessels; Membrane Proteins; Mucoproteins; Pancreatic Ducts; Pancreatitis

The major keratins in the pancreas and liver are keratins 8 and 18 (K8/K18), but their function seemingly differs in that liver K8/K18 are essential cytoprotective proteins, whereas pancreatic K8/K18 are dispensable. This functional dichotomy raises the hypothesis that K8-null pancreata may undergo compensatory cytoprotective gene expression. We tested this hypothesis by comparing the gene expression profile in pancreata of wild-type and K8-null mice. Most prominent among the up-regulated genes in K8-null pancreas was mRNA for regenerating islet-derived (Reg)-II, which was confirmed by quantitative reverse transcription-polymerase chain reaction and by an anti-Reg-II peptide antibody we generated. Both K8-null and wild-type mice express Reg-II predominantly in acinar cells as determined by in situ hybridization and immunostaining. Analysis of Reg-II expression in various keratin-related transgenic mouse models showed that its induction also occurs in response to keratin cytoplasmic filament collapse, absence, or ablation of K18 Ser52 but not Ser33 phosphorylation via Ser-to-Ala mutation, which represent situations associated with predisposition to liver but not pancreatic injury. In wild-type mice, Reg-II is markedly up-regulated in two established pancreatitis models in response to injury and during the recovery phase. Thus, Reg-II is a likely mouse exocrine pancreas cytoprotective candidate protein whose expression is regulated by keratin filament organization and phosphorylation.

Topics: Acute Disease; Amino Acid Sequence; Animals; Cytoplasm; Disease Models, Animal; Keratins; Mice; Molecular Sequence Data; Mutation; Pancreas, Exocrine; Pancreatitis; Pancreatitis-Associated Proteins; Phosphorylation; Proteins; Up-Regulation

Genetic predispositions play a major role in the development of chronic pancreatitis. Recently, a mutation in the keratin 8 gene (G62C) was reported to be associated with chronic pancreatitis in Italy. We determined whether mutations in the keratin 8 gene are associated with familial, sporadic and alcoholic recurrent acute or chronic pancreatitis in a population from the United States.. We investigated the relevant genomic region of the keratin 8 gene in 80 patients with familial pancreatitis without a cationic trypsinogen (PRSS1) gene mutation from 52 different families, 21 patients with familial hereditary pancreatitis and a PRSS1 mutation from 20 different families, 126 patients with sporadic pancreatitis without a PRSS1 mutation, 61 patients with alcoholic pancreatitis and 271 controls by direct DNA sequencing.. We found the heterozygous G62C mutation in n = 3/80 patients (n = 2/52 patients from different families, 3.8%) with familial pancreatitis without PRSS1 mutation and in n = 3/126 patients (2.4%) with sporadic pancreatitis. We detected an adjacent heterozygous I63V mutation in n = 2/80 patients (n = 2/52 patients from different families, 3.8%) with familial pancreatitis without PRSS1 mutation and in n = 1/61 patients (1.6%) with alcoholic pancreatitis. We found the G62C mutation in n = 2/271 controls (0.7%) and the I63V mutation in n = 2/271 controls (0.7%). There were no statistically significant differences in the genotype frequencies between patients and controls (p > 0.05). Screening of additional available family members revealed that these variants did not segregate with the disease phenotype. There was no statistically significant difference in the frequency of these keratin 8 variants between patients with chronic pancreatitis and controls (p > 0.05).. These keratin 8 variants are not associated with familial, sporadic or alcoholic pancreatitis.

Topics: Adult; Codon; DNA; Female; Humans; Keratins; Male; Mutation; Pancreatitis; Pancreatitis, Alcoholic; Phenotype; Trypsin; Trypsinogen; United States

Keratin polypeptides 8 and 18 (K8/K18) are the major intermediate filament proteins of pancreatic acinar cells and hepatocytes. Pancreatic keratin function is unknown, whereas hepatocyte keratins protect from mechanical and non-mechanical forms of stress. We characterized steady-state pancreatic keratin expression in Balb/c mice after caerulein and choline-deficient ethionine-supplemented diet (CDD), or on exposure to the generalized stresses of heat and water immersion. Keratins were studied at the protein, RNA and organizational levels. Isolated acini were used to study the role of nuclear factor (NF)-kappaB using selective inhibitors. Keratins were found to be abundant proteins making up 0.2%, 0.3% and 0.5% of the total cellular protein of pancreas, liver and small intestine, respectively. Caerulein and CDD caused a threefold transcription-mediated overall increase in K8/K18/K19/K20 proteins. Keratin overexpression begins on tissue recovery, peaks 2 days after caerulein injection, or 1 day after CDD discontinuation, and returns to basal levels after 10 days. K19/K20-containing cytoplasmic filaments are nearly absent pre-injury but form post-injury then return to their original membrane-proximal distribution after 10 days. By contrast, generalized stresses of heat or water-immersion stress do not alter keratin expression levels. Caerulein-induced keratin overexpression is associated with NF-kappaB activation when tested using ex vivo acinar cell cultures. In conclusion, keratins are abundant proteins that can behave as stress proteins in response to tissue-specific but not generalized forms of injury. Pancreatic keratin overexpression is associated with NF-kappaB activation and may serve unique functions in acinar or ductal cell response to injury.

Topics: Animals; Ceruletide; Choline Deficiency; Diet; Ethionine; Fever; Gene Expression Regulation; Hot Temperature; Intestine, Small; Keratins; Liver; Mice; Mice, Inbred BALB C; NF-kappa B; Organ Specificity; Pancreas; Pancreatitis; RNA, Messenger; Transcriptional Activation; Water

Among the three major cytofilament proteins, keratin (K8/K18/K19) expression increases nearly threefold upon pancreas or liver injury, while actin and tubulin expressions are considered relatively stable. K8/K18 serves essential hepatocyte cytoprotective functions yet appears dispensable in K8-null mouse pancreata, which led us to hypothesize that actin or tubulin expressions may increase after pancreatic injury. Balb/c and FVB/n mice manifested different susceptibility to injury in two pancreatitis models, with significant induction of actin protein (threefold) and RNA after moderate or severe but not mild injury. Alterations in tubulin expression were less prominent. Basally, K8-null and wild-type pancreata expressed similar actin and tubulin levels, while the injury-induced actin protein but not RNA was more pronounced in K8-null mice. K7/K18/K19/K20 were also induced in K8-null mice after injury. Ex vivo, caerulein-triggered pancreatitis caused protein degradation (actin approximately or = tubulin > keratins) and mRNA up-regulation that was blocked by actinomycin-D (act-D) (actin approximately or = tubulin approximately or = keratin) or by NF-kappaB inhibition (keratins > actin approximately or = tubulin). Hence, actin is not as static as previously held and is overexpressed after moderate to severe pancreatic injury while keratins are induced after minimal injury. Keratin and actin induction may serve protective roles in pancreatic injury.

Topics: Actins; Animals; Ceruletide; Cytoskeleton; Dactinomycin; Disease Susceptibility; Female; Immunoblotting; Keratin-8; Keratins; Male; Mice; Mice, Inbred BALB C; Mice, Knockout; NF-kappa B; Pancreas; Pancreatic Diseases; Pancreatitis; Protein Synthesis Inhibitors; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Tubulin; Up-Regulation

Topics: Animals; Antibodies; Caspases; Cell Line; Epithelial Cells; Gallbladder; Glycosylation; Humans; Immunoprecipitation; Intestine, Small; Keratins; Liver; Liver Regeneration; Male; Mice; Pancreatitis; Phosphorylation; Protein Processing, Post-Translational; Staining and Labeling

Topics: Chronic Disease; Humans; Keratin-8; Keratins; Pancreatitis

Keratin 8 (K8) and 18 (K18) are the major components of the intermediate filament cytoskeleton of pancreatic acinar cells and play a relevant role in pancreatic exocrine homeostasis. Transgenic mice for K8 have shown to display progressive exocrine pancreas alterations, including dysplasia, loss of acinar architecture, redifferentiation of acinar to ductal cells, inflammation, fibrosis, and substitution of exocrine tissue by adipose tissue.. To investigate whether mutations in the keratin 8 gene are associated with chronic pancreatitis.. Mutations in the keratin 8 gene were determined by polymerase chain reaction/restriction fragment length polymorphism in 67 chronic pancreatitis patients and 100 normal controls. Sequence analysis was performed when necessary.. Glycine-to-cysteine mutations at position 61 (G61C) of the keratin 8 gene were found in six patients (8.9 vs. 0%, p(c) < 0.003, odds ratio = 21.24, confidence interval = 2.74-164.42); none of the controls presented the mutation. No tyrosine-to-histidine mutations at position 53 (Y53H) were detected in any subject.. G61C mutation of the keratin 8 gene, together with other environmental factors and/or genetic factors, could predispose to chronic pancreatitis, by interfering with the normal organization of keratin filaments.

Topics: Chronic Disease; Female; Humans; Keratin-8; Keratins; Male; Middle Aged; Mutation; Pancreatitis

Cure for ductal adenocarcinoma of the pancreas is restricted to resectable tumors, but survival after surgery is still poor. Despite apparently curative resection, these cancers rapidly recur. Thus, the present pathologic examination should be enriched by sensitive methods to detect minimal residual disease. In a prospective setting we studied the frequency of minimal residual disease after curative resection by routine histopathology, immunohistology, and polymerase chain reaction (PCR) for mutated K-ras. Furthermore, the prognostic implication of detecting of MRD was determined. Prospectively, tumor tissue and corresponding paraaortic lymph nodes were obtained from 78 patients, who underwent surgery for pancreatic head tumors between 1999 and 2001. Sixty-nine of 78 cases were diagnosed for ductal adenocarcinoma (study group), whereas nine cases were diagnosed for benign pancreatic tumors (control group). Paraaortic lymph nodes were examined in step sections by routine histopathology (hematoxylin and eosin) and immunohistology using a pan-cytokeratin antibody. DNA of the primary tumor and corresponding paraaortic lymph nodes were analyzed by PCR-based assays with respect to mutated K-ras in codon 12. The recurrence-free survival and overall survival were correlated with the results of the latter methods. In 3 of 69 patients tumor cells were detected in paraaortic lymph nodes by routine histopathology and in 5 of 69 patients by immunohistology. K-ras mutations were detected in 42 of 69 ductal adenocarcinomas (61%), whereas 12 (17%) were positive in paraaortic lymph nodes. All of the latter patients had recurrence after surgery and a significant poorer survival than those without mutated K-ras. Furthermore, paraaortic lymph nodes diagnosed for K-ras mutation were independent prognostic markers in multivariate analysis. In the control group K-ras mutations were detected in one adenoma of Vater's papilla but not in paraaortic lymph nodes. Tumor cell DNA can be detected more sensitively by the described PCR method than with hematoxylin and eosin or immunohistologic staining, leading to a higher sensitivity for detection of micrometastases. The described PCR method clearly determines subgroups of patients after curative resection with early recurrence and poor survival and could therefore enrich the pathologic examination.

Topics: Adenocarcinoma; Aged; Aorta; Chronic Disease; Cystadenoma; Diagnostic Tests, Routine; DNA, Neoplasm; Female; Genes, ras; Humans; Immunohistochemistry; Keratins; Lymphatic Metastasis; Male; Middle Aged; Multivariate Analysis; Mutation; Neoplasm Staging; Pancreatic Neoplasms; Pancreaticoduodenectomy; Pancreatitis; Polymerase Chain Reaction; Polymorphism, Restriction Fragment Length; Predictive Value of Tests; Prognosis; Sequence Analysis, DNA; Survival Analysis

Histopathological changes of biopsied pancreata were examined in three diabetic patients with autoimmune chronic pancreatitis (ACP). We found intra- and periinsular mononuclear cell (MNC)-mainly CD8+ T cell-infiltration as well as MNC infiltration around the ductal cells. Islet beta cell volume decreased significantly. Some ductal cells expressed insulin and insulin promoter factor-1 concomitantly in the affected pancreas. These findings provide new insight toward understanding the pathological mechanisms of corticosteroid treatment-responsive diabetes associated with ACP.

Topics: Adrenal Cortex Hormones; Aged; Autoimmune Diseases; Biopsy; CD8-Positive T-Lymphocytes; Diabetes Complications; Diabetes Mellitus; HLA Antigens; Humans; Immunohistochemistry; Insulin; Islets of Langerhans; Keratins; Male; Middle Aged; Pancreatitis

Based on the fact that pancreatic carcinoma is still associated with poor outcome, the aim of the study was to determine frequency of early tumor cell dissemination using immunohistology in lymph nodes classified as tumor-free by conventional histopathology.. Fifteen patients with ductal pancreatic carcinoma and 10 patients with carcinoma of the papilla of Vater underwent radical tumor resection (resection status R0, tumor staging pTxpN0M0). In total, 229 lymph nodes classified as tumor-free by histopathology were investigated for disseminated tumor cells using antibodies against cytokeratin and CA19-9. As control, 81 lymph nodes obtained from patients with chronic pancreatitis were analyzed.. In 55 of 229 lymph nodes (26.3%), cytokeratin-positive, disseminated tumor cells were detected. Cytokeratin-positive cells were found in at least one resected lymph node of each patient with ductal carcinoma of the pancreatic head (100%), whereas in patients with carcinoma of the papilla of Vater, no disseminated tumor cells were detected using the antibody against cytokeratin. Similarly, there was no detection of tumor cells (false-positive) in patients with chronic pancreatitis. In contrast, CA19-9 antigen was detectable in resected lymph nodes of each of the 25 carcinoma patients (pancreatic carcinoma and carcinoma of the papilla of Vater). Interestingly, 52 of 81 lymph nodes (64.2%) from the control group (chronic pancreatitis) were false-positive.. Detection of disseminated tumor cells in lymph nodes using an antibody against cytokeratin is specific and suitable while use of an antibody against CA19-9 is not recommendable because of the high rate of false-positive results. The results may indicate that ductal pancreatic carcinoma generates early dissemination of tumor cells into lymph nodes. This may be one explanation for the poor outcome of this carcinoma compared with that of the carcinoma of the papilla of Vater (14 versus 48 months P < 0.05).

Topics: Adenocarcinoma; Adult; Aged; Ampulla of Vater; Biomarkers, Tumor; CA-19-9 Antigen; Carcinoma; Chronic Disease; Common Bile Duct Neoplasms; Female; Humans; Immunohistochemistry; Keratins; Lymph Nodes; Lymphatic Metastasis; Male; Middle Aged; Neoplasm Staging; Pancreatic Neoplasms; Pancreatitis; Predictive Value of Tests; Prognosis

Pancreatic acinar cells express keratins 8 and 18 (K8/18), which form cytoplasmic filament (CF) and apicolateral filament (ALF) pools. Hepatocyte K8/18 CF provide important protection from environmental stresses, but disruption of acinar cell CF has no significant impact. We asked whether acinar cell ALF are important in providing cytoprotective roles by studying keratin filaments in pancreata of K8- and K18-null mice. K8-null pancreas lacks both keratin pools, but K18-null pancreas lacks only CF. Mouse but not human acinar cells also express apicolateral keratin 19 (K19), which explains the presence of apicolateral keratins in K18-null pancreas. K8- and K18-null pancreata are histologically normal, and their acini respond similarly to stimulated secretion, although K8-null acini viability is reduced. Absence of total filaments (K8-null) or CF (K18-null) does not increase susceptibility to pancreatitis induced by caerulein or a choline-deficient diet. In normal and K18-null acini, K19 is upregulated after caerulein injury and, unexpectedly, forms CF. As in hepatocytes, acinar injury is also associated with keratin hyperphosphorylation. Hence, K19 forms ALF in mouse acinar cells and helps define two distinct ALF and CF pools. On injury, K19 forms CF that revert to ALF after healing. Acinar keratins appear to be dispensable for cytoprotection, in contrast to hepatocyte keratins, despite similar hyperphosphorylation patterns after injury.

Topics: Actins; Animals; Cell Survival; Electrophoresis, Polyacrylamide Gel; Epithelial Cells; Female; Humans; Keratins; Male; Mice; Pancreatitis; Phosphorylation

cDNA representational difference analysis (cDNA-RDA) is a polymerase-chain-reaction-coupled subtractive and kinetic enrichment procedure for the isolation of differentially expressed genes. In this study, the technique was used to isolate novel genes specifically expressed in pancreatic cancer. cDNA-RDA was done on cDNA reverse transcribed from a poly(A)+ mRNA pool made from 10 cancer tissues (tester) by using as a driver a cDNA from a poly(A)+ mRNA pool made from a combination of 10 tissues of chronic pancreatitis and 10 healthy pancreatic tissues. The use of chronic pancreatitis in addition to healthy pancreas mRNA in the driver preparation eliminated the influence of stromal tissue components present as contamination in the cancer-specific preparations. Such cDNA-RDA led to the isolation of 16 distinct, cancer-specific gene fragments. These were confirmed to be overexpressed in pancreatic cancer tissues by Northern blot analysis. Sequence analysis revealed homologies to five genes previously implicated in the carcinogenesis of the pancreas or other tissues. Eleven fragments had no significant homology to any known gene and thus represent novel candidate disease genes. The experiments demonstrate that cDNA-RDA is a reproducible and highly efficient method for the identification of novel genes with cancer-specific expression.

Topics: Annexin A3; Base Sequence; DNA, Complementary; DNA, Neoplasm; Fibronectins; Gene Expression; Humans; Insulin-Like Growth Factor Binding Protein 1; Keratins; Molecular Sequence Data; Pancreatic Neoplasms; Pancreatitis; Polymerase Chain Reaction

Multinucleated giant cells in the pancreas (five giant cell carcinomas, a mucinous cystadenocarcinoma attended with many osteoclast-like giant cells, 42 invasive ductal carcinomas and 29 chronic pancreatitises) were examined. Three types of multinucleated giant cell were identified: epithelial type, coexpressive type, mesenchymal type. Epithelial type expressed epithelial markers, such as keratin and EMA in 23 ductal carcinomas. Coexpressive type expressed both epithelial markers and mesenchymal marker vimentin was in four ductal carcinomas. Mesenchymal type expressed mesenchymal markers, vimentin and CD68 in four osteoclastoid type giant cell carcinomas, the mucinous cystadenocarcinoma, six ductal carcinomas and ten chronic pancreatitises. Epithelial and coexpressive type were considered to be epithelial neoplastic origin, those had bizarre appearance and transitional area from definite adenocarcinoma area. Vimentin expression is associated with sarcomatous proliferation. Mesenchymal type was considered to be nonneoplastic and a certain type of macrophage polykaryons.

Topics: Adult; Aged; Antigens, CD; Antigens, Differentiation, Myelomonocytic; Biomarkers; Carcinoma, Ductal, Breast; Carcinoma, Giant Cell; Chronic Disease; Cystadenocarcinoma, Mucinous; Female; Humans; Immunohistochemistry; Keratins; Male; Middle Aged; Mucin-1; Pancreatic Neoplasms; Pancreatitis; Vimentin

The intermediate filament (IF) proteins present in the normal and pathological exocrine human pancreas were studied by immunolocalization using antibodies to cytokeratins (CKs) and vimentin. Acinar cells of normal pancreas showed a presence of simple CKs 8 and 18. Duct epithelium consistently expressed CKs 7, 8, 18 and 19 whereas centroacinar cells were rather low in CK 7. A subpopulation of CK 4 cells was detected in inter-intralobular ducts. In addition, some ducts contained individual cells or groups of cells that were positive for the stratification-related CKs (CKs 4, 5, 13, 15, 16). All pancreatic ductal adenocarcinomas regularly expressed CKs 7, 8, 18, 19 and were also positive for the 34 beta E12 antibody. Cytokeratin 4 was detected in a minor population of tumor cells. Pancreatic carcinoma also contained minor amounts of stratification-related CKs in variable combinations. Mucinous cystoadenocarcinoma showed the presence of CKs 7, 8, 18, 19 and was also positive for 34 beta E12, whereas the serous microcystic tumor presented CKs 8, 18, 19 and a variable amount of CKs 4 and 7. The duct-ductular alterations of the exocrine pancreas contained a different combination and distribution of CK isoforms similar to normal pancreatic ductal system. Mucinous hypertrophy and pyloric gland metaplasia reacted with antibodies to CKs 7, 8, 18 and 19. Vimentin was focally present both in normal and neoplastic tissue. Our results indicate that pancreatic ducts are characterized by an intrinsic "biliary-pancreatic duct type" immunoprofile (CKs 7, 8, 18 and 19), in contrast to acinar cells expressing exclusively CKs 8 and 18. We also detected a subpopulation of ducts regularly expressing CK 4. Surprisingly, several stratification-related CKs were detected both in normal and neoplastic exocrine pancreas. Moreover, the differentiation phenotypes of pancreatic tumors were reminiscent of normal cellular compartments.

Topics: Adenocarcinoma; Antibodies, Monoclonal; Biomarkers, Tumor; Humans; Intermediate Filament Proteins; Keratins; Pancreas; Pancreatic Neoplasms; Pancreatitis

Expression of intermediate filaments (IF) is regulated during development and differentiation. The authors have studied the expression of vimentin and cytokeratins (CK) 4, 7, 8, 13, 18, 19 in normal pancreas, chronic pancreatitis, and pancreas cancer using monoclonal antibodies. Immunohistochemical assays were performed on fresh frozen tissue sections and on cultured pancreas cancer cells using the streptavidin-peroxidase method. In normal pancreas, acinar cells expressed CK 8 and 18, whereas ductal cells expressed CK 7, 8, 18, and 19. CK 4 was expressed by 5-10% of pancreas duct cells in all specimens of normal pancreas. CK 13 was not detected in any epithelial cells of normal pancreas or pancreatitis. CK 7, 8, 18, and 19 were homogeneously expressed in all pancreas cancers, whereas CK 4 was expressed only in 5-50% of cells in 10/16 tumors. Foci of squamous metaplasia expressed CK 13 but showed partial loss of expression of CK 7, 8, 18, and 19. Thirteen pancreas cancer cell lines examined showed homogeneous expression of CK 7, 8, 18, and 19; 2/11 lines expressed CK 4 weakly, and 6/11 expressed vimentin. CK 13 was not detected in any of the lines. These results indicate that pancreas cancer cells consistently express cytokeratin polypeptides characteristic of ductal epithelial cells and that this phenotype is retained in pancreas cancer cell lines. In addition, squamous metaplasia is associated with a coordinate change in the expression of CK polypeptides.

Topics: Biomarkers; Cell Differentiation; Chronic Disease; Humans; Immunohistochemistry; Intermediate Filament Proteins; Keratins; Pancreas; Pancreatic Neoplasms; Pancreatitis; Reference Values; Tumor Cells, Cultured

Autoantibodies reacting with human pancreatic exocrine cells were investigated by immunofluorescent techniques in 107 patients with Type 1 (insulin-dependent) diabetes mellitus, 20 first-degree relatives of the Type 1 diabetic patients, 347 patients with Type 2 (non-insulin-dependent) diabetes, 34 with alcoholic pancreatitis, 26 with rheumatoid arthritis and 107 normal control subjects. Both immunoblotting analysis and double-immunostaining methods were used to characterize the antigens targeted by the pancreatic exocrine cell autoantibodies. Sera positive for human pancreatic exocrine cell cytoplasm, producing a "fine fibrillar" pattern, were found in 21% (23/107) of the Type 1 diabetic patients. The autoantibodies were present in 39% (15/38) of Type 1 diabetic patients diagnosed within 3 months, and the prevalence decreased with duration of diabetes. The antibodies were of the IgM class in 87% (13/15) of recent-onset Type 1 diabetes cases, but IgG-autoantibodies became more prevalent with increasing duration of diabetes. Three out of 347 (0.9%) Type 2 diabetic patients and 4 of 20 (20%) first-degree relatives of Type 1 diabetic patients had autoantibodies targeted against pancreatic exocrine cells. None of the patients with alcoholic pancreatitis or rheumatoid arthritis and none of the control subjects had these antibodies. Immunoblotting analysis and double-immunostaining demonstrated that the autoantibodies reacted with 40 kilodalton cytokeratin in pancreatic exocrine cell cytoplasm. The antibody was absorbed by the Triton X-100-insoluble fraction of pancreatic extract. These results indicate the presence of distinct autoantibodies to pancreatic exocrine cells in Type 1 diabetes. This suggests the provocative concept that the cytoskeletal system of pancreatic exocrine cells is involved in the pathogenetic process of Type 1 diabetes.

Topics: Adolescent; Adult; Alcoholism; Arthritis, Rheumatoid; Autoantibodies; Chronic Disease; Diabetes Mellitus, Type 1; Family; Female; Fluorescent Antibody Technique; Humans; Islets of Langerhans; Keratins; Male; Pancreas; Pancreatitis; Reference Values