Masaya Ohana

Autoimmune-related pancreatitis is associated with autoantibodies and a Th1/Th2-type cellular immune response

BACKGROUND & AIMS Although autoimmunity may be involved in some cases of pancreatitis, the mechanism is still unknown. To clarify this, we studied serum autoantibodies, subsets of lymphocytes, and the Th1/Th2 balance of cellular immune responses in patients with autoimmune-related pancreatitis (AIP). METHODS Seventeen patients with AIP (8 men and 9 women; age, 53.2 +/- 13.0 years) were studied. Autoantibodies including antilactoferrin (ALF) or carbonic anhydrase II antibody (ACA-II) were examined using the enzyme-linked immunosorbent assay (ELISA) or the indirect fluorescein antibody method. Intracellular cytokines (interferon gamma and interleukin 4) and subtypes of peripheral blood lymphocytes were examined by flow cytometry and ELISA. RESULTS More than one autoantibody was observed in all 17 patients. Serum antinuclear antibody was detected in 13 of 17 patients, ALF antibody in 13, ACA-II antibody in 10, rheumatoid factor in 5, and anti-smooth muscle antibody in 3, but antimitochondrial antibody in none. The serum levels of ACA-II and LF antibody were not correlated. HLA-DR(+)CD8(+) and HLA-DR(+)CD4(+) cells were significantly increased in peripheral blood (P < 0.05). CD4(+) cells producing interferon gamma and the secreted levels were significantly increased compared with those in controls (P < 0.05), but interleukin 4 was not increased. CONCLUSIONS An autoimmune mechanism against CA-II or LF, and Th1-type immune response, may be involved in AIP.

Clinical analysis of autoimmune-related pancreatitis

Abstract OBJECTIVE: Several investigators have reported on autoimmune-related pancreatitis, but the clinical findings and pathophysiology still remain unclear. To clarify it, we analyzed eight patients with autoimmune pancreatitis. METHODS: We evaluated clinical findings in eight patients (four men and four women) with autoimmune-related pancreatitis. Patients were aged 45–73 yr (mean, 57.5 yr). We examined blood chemistry and immunological studies, including autoantibodies against lactoferrin or carbonic anhydrase II, and compared ERCP images with clinical findings. In two patients, we studied the subset of lymphocytes infiltrating in the pancreas by immunohistochemistry and flow cytometry. RESULTS: Four of eight patients had jaundice, two had renal dysfunction, two had abdominal pain, and two had back pain. Three patients were complicated with other autoimmune diseases. Three patients showed abnormal pancreatic exocrine function by an N -benzoyl- L -tyrosyl- para -aminobenzoic acid excretion test. Antinuclear antibody was detected in four of eight patients, antilactoferrin antibody in three of six, anticarbonic anhydrase II antibody in two of six, antismooth muscle antibody in two of seven, and rheumatoid factor in one of eight. All eight patients showed segmental stenosis of the main pancreatic duct by ERCP. Four patients showed stenosis of the common bile duct as well as the pancreatic duct. Microscopic findings showed infiltration of CD4-positive lymphocytes around the pancreatic duct, and HLA-DR was expressed on both CD4-positive cells and pancreatic duct cells. In two patients, stenosis of the pancreatic duct improved by prednisolone. CONCLUSIONS: Autoimmune mechanism may be involved in some patients with idiopathic pancreatitis associated with hypergammaglobulinemia.

Risk of Cancer in Patients With Autoimmune Pancreatitis

OBJECTIVES:Although simultaneous occurrences of autoimmune pancreatitis (AIP) and cancer are occasionally observed, it remains largely unknown whether cancer and AIP occur independently or these disorders are interrelated. The aim of this study was to examine the relationship between AIP and cancer.METHODS:We conducted a multicenter, retrospective cohort study. One hundred and eight patients who met the Asian diagnostic criteria for AIP were included in the study. We calculated the proportion, standardized incidence ratio (SIR), relative risk, and time course of cancer development in patients with AIP. We also analyzed the clinicopathological characteristics of AIP patients with cancer in comparison with those without cancer.RESULTS:Of the 108 AIP patients, 18 cancers were found in 15 patients (13.9%) during the median follow-up period of 3.3 years. The SIR of cancer was 2.7 (95% confidence interval (CI) 1.4–3.9), which was stratified into the first year (6.1 (95% CI 2.3–9.9)) and subsequent years (1.5 (95% CI 0.3–2.8)) after AIP diagnosis. Relative risk of cancer among AIP patients at the time of AIP diagnosis was 4.9 (95% CI 1.7–14.9). In six of eight patients whose cancer lesions could be assessed before corticosteroid therapy for AIP, abundant IgG4-positive plasma cell infiltration was observed in the cancer stroma. These six patients experienced no AIP relapse after successful cancer treatment.CONCLUSIONS:Patients with AIP are at high risk of having various cancers. The highest risk for cancer in the first year after AIP diagnosis and absence of AIP relapse after successful treatment of the coexisting cancers suggest that AIP may develop as a paraneoplastic syndrome in some patients.

Experimental immune-mediated pancreatitis in neonatally thymectomized mice immunized with carbonic anhydrase II and lactoferrin

We previously reported that autoantibodies against carbonic anhydrase II and lactoferrin are frequently identified in patients with autoimmune-related pancreatitis. To clarify the role of carbonic anhydrase II and lactoferrin, we created animal models of autoimmune pancreatitis by immunizing neonatally thymectomized mice with carbonic anhydrase II and lactoferrin and also by transferring immunized spleen cells to nude mice. Neonatally thymectomized BALB/c mice were immunized with carbonic anhydrase II or lactoferrin followed by three booster injections (n = 10 in each group). We transferred whole, CD4+, or CD8+ spleen cells prepared from immunized neonatally thymectomized mice to nude mice (n = 5 in each group). Gene expression of IFN-γ and IL-4 was investigated using semiquantitative reverse transcription-polymerase chain reaction. Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling staining was used to examine apoptosis. In immunized neonatally thymectomized mice, the prevalence of inflammation was significantly higher in the pancreas. Inflammation was present in all mice receiving whole or CD4+ cells. There was no change in any of the mice receiving CD8+ cells or nonimmunized spleen cells. Carbonic anhydrase II or lactoferrin-immunized mice had apoptotic duct cells or acinar cells, respectively. Expression of the IFN-γ gene was up-regulated in each group. Similar findings were observed in the salivary glands and liver. An immunologic mechanism against carbonic anhydrase II or lactoferrin is involved in the pathogenesis of these pancreatitis models, in which the effector cells are Th1-type CD4+ T cells.

Multiple pancreatic masses associated with autoimmunity

A 59-year-old woman was detected to have a high titer of serum gamma-globulin, positive antinuclear antibody and multiple pancreatic masses. In the course of 1 yr, Sjögrens syndrome developed, and her pancreatic masses spread diffusely and compressed the main pancreatic duct. A pancreatic biopsy by an exploration of the abdomen showed that many CD4 positive T-lymphocytes had infiltrated to the ducts and acinar cells expressing HLA-DR antigens. This suggested a diagnosis of autoimmune-related pancreatitis. She was treated with oral prednisolone, and a marked improvement of the above abnormal findings followed. In this report, a case of autoimmune-related multiple pancreatic masses associated with Sjögrens syndrome is presented, and a possible mechanism is discussed.

Involvement of myeloid dendritic cells in the development of gastric secondary lymphoid follicles in Helicobacter pylori-infected neonatally thymectomized BALB/c mice

ABSTRACT We previously described an animal model of Helicobacter pylori-induced follicular gastritis in neonatally thymectomized (nTx) mice. However, it is still not clear whether antigen-presenting dendritic cells (DCs) in the stomach have a role in the development of secondary follicles in H. pylori-infected nTx mice. We investigated the distribution of DC subsets using this model and examined their roles. To identify lymphoid and myeloid DCs, sections were stained with anti-CD11c (pan-DC marker) in combination with anti-CD8α (lymphoid DC marker) or anti-CD11b (myeloid DC marker) and were examined with a confocal microscope. Expression of macrophage inflammatory protein 3α (MIP-3α), which chemoattracts immature DCs, was analyzed by real-time PCR and immunohistochemistry. Follicular dendritic cells (FDCs) were stained with anti-SKY28 antibodies. In noninfected nTx mice, a few myeloid and lymphoid DCs were observed in the bottom portion of the lamina propria, whereas in H. pylori-infected nTx mice, there was an increased influx of myeloid DCs throughout the lamina propria. FDC staining was also observed in the stomachs of members of the infected group. MIP-3α gene expression was upregulated in the infected nTx group, and the immunohistochemistry analysis revealed MIP-3α-positive epithelial cells. These data suggest that H. pylori infection upregulates MIP-3α gene expression in gastric epithelial cells and induces an influx of myeloid DCs in the lamina propria of the gastric mucosa in nTx mice. Myeloid DCs and FDCs might contribute to the development of gastric secondary lymphoid follicles in H. pylori-infected nTx mice.

Analysis of Cytokines in the Early Development of Gastric Secondary Lymphoid Follicles in Helicobacter pylori-Infected BALB/c Mice with Neonatal Thymectomy

ABSTRACT Immunological interaction between the host and Helicobacter pylori seems to play a critical role in follicular formation in gastric mucosa. We reported H. pylori-induced follicular gastritis model using neonatally thymectomized mice. In this study, we investigated the involvement of various cytokines in this model. BALB/c mice were thymectomized on the third day after birth (nTx). At 6 weeks old, these mice were orally infected with H. pylori. Histological studies showed that follicular formation occurred from 8 weeks after the infection and that most of the infiltrating lymphocytes were CD4+ and B cells. Neutrophils increased transiently at 1 week after the infection. Gamma interferon, interleukin-7 (IL-7), and IL-7 receptor were expressed in the stomach of the nTx mice irrespective of the infection. In contrast, expressions of the tumor necrosis factor alpha, IL-4 and lymphotoxin-α genes were remarkably upregulated by the infection. Our findings suggest that follicular formation may require cooperative involvement of a Th2-type immune response, tumor necrosis factor alpha and lymphotoxin-α in addition to the Th1-type immune response in H. pylori-induced gastritis in nTx mice.

Helicobacter felis-induced gastritis was suppressed in mice overexpressing thioredoxin-1

Thioredoxin-1 (TRX-1) is a redox-active protein involved in scavenging reactive oxygen species and regulating redox-sensitive transcription factors. TRX-1 is induced in various inflammatory conditions and shows cytoprotective action. We investigated the roles of TRX-1 in the host defense mechanism against Helicobacter felis (H. felis) infection. Transgenic (TG) mice overexpressing human TRX-1 and wild-type (WT) mice were orally inoculated with H. felis. After 2 months, histology, oxidative damage, and gene expression of several cytokines, including macrophage inflammatory protein-2 (MIP-2), a murine equivalent to interleukin (IL)-8, in the gastric mucosa were investigated. Furthermore, the effects of TRX-1 on oxidative stress and neutrophil migration were studied both in vivo and in vitro. The gastric mucosa was thickened in H. felis-infected WT mice, but not in infected TRX-1-TG mice. Histologically, all H. felis-infected WT mice developed moderate-to-severe gastritis, whereas the development of gastritis was significantly suppressed in infected TRX-1-TG mice. Oxidative damage markers, 8-hydroxy-2′-deoxyguanosine and malondialdehyde, increased in the stomach of infected WT mice, but not TRX-1-TG mice. Upregulation of IL-1β and tumor necrosis factor-α gene expression in H. felis-infected TRX-1-TG mice was significantly lower than in WT mice. However, upregulation of MIP-2 and IL-7 was not different between the two groups. TRX-1 suppressed oxidative cytotoxicity and DNA damage, and inhibited neutrophil migration both in vivo and in vitro. The present study suggests that overexpression of TRX-1 suppresses H. felis-induced gastritis by inhibiting chemotaxis of neutrophils and reducing oxidative stress.

Efficacy of probiotic treatment with Bifidobacterium longum 536 for induction of remission in active ulcerative colitis: A randomized, double‐blinded, placebo‐controlled multicenter trial

We conducted a randomized, double‐blinded, placebo‐controlled trial to investigate the efficacy of Bifidobacterium longum 536 (BB536) supplementation for induction of remission in Japanese patients with active ulcerative colitis (UC).

Antilactoferrin Antibodies in Autoimmune Liver Diseases

Objective:Lactoferrin, an immunoregulatory protein in mucosal secretions, is one of the target antigens to perinuclear antineutrophil cytoplasmic antibodies (P-ANCAs). Circulating lactoferrin is cleared in the liver, but little is known about the implication of lactoferrin in hepatic inflammation. To evaluate the implication of immunological response to lactoferrin, we examined antilactoferrin antibodies in autoimmune liver diseases.Methods:Fourteen patients with primary biliary cirrhosis (PBC), 14 with autoimmune hepatitis (AIH), five with autoimmune cholangitis (AIC), six with chronic hepatitis C, and five with chronic hepatitis B were studied. We evaluated autoantibodies to lactoferrin in the sera of the patients by the Western Immunoblotting method.Results:Sera of five of the 14 patients (35.7%) with PBC, four of the 14 patients (28.6%) with AIH, and five of the five patients (100%) with AIC contained autoantibodies to human lactoferrin, but none with hepatitis B or C had them. The higher prevalence of serum antibodies to human lactoferrin was shown to be higher in patients with AIC than with hepatitis B (p < 0.01), hepatitis C (p < 0.01), PBC (p < 0.05), and AIH (p < 0.05).Conclusion:Lactoferrin located in bile ducts and liver cells is one of the candidates of target antigens in autoimmune liver diseases, especially in AIC.