(PBMCs) from 35 PBC patients (31 female, all anti-PDC-E2 antibody positive) and 10 healthy control women (matched for age, all anti-PDC-E2 antibody negative) were tested. PDC-E2 specific T-cell responses was evaluated using an IFN- ELISpot assay (Mabtech, Sweden) and flow cytometry, staining for CD4+IFN + T Cells after stimulating PBMCs with PDC- E2 163-176 (35 patients tested) or 76 20aa overlapping peptides spanning the entire PDC-E2 comprising 12 pools, each consisting of 6-7 peptides (22 patients tested). In ELISpot assays reactivity was defined as Antigen Specific Spot Forming Units (AgSpSFU) by extracting mean SFU in the absence of the peptide(s) from SFU in the presence of it. Statistically significant antigen specific IFN- production by CD4+ T cell was calculated by comparing unstimulated and stimulated populations. Results: Distinct profile of peptide pool recognition was noted amongst patients. Overall, CD4+ T lymphocytes from 17 out of 22 patients (77.3%) showed statistically significant production of IFN- after stimulation with at least one pool of peptides; 1/22 (4.5%) recognized 6 pools, 4/22 (18.2%) 5 pools, 3/22 (13.6%) 4 pools, 3/22 (13.6%) 3 pools, 3/22 (13.6%) 2 pools and 3/22 (13.6%) just one pool. The most immunodominat pool of peptides was pool#1 (9/22, 40.9%), followed by pool#5 (7/22, 31.8%) and pool#2 (6/22, 27.3%). Only 3/35 patients (8.6%) recognized PDC-E2 163-176 . Conclusions: Human PDC-E2 163-176 is a subdominant epitope of T-cells in Greek PBC patients. PDC-E2 specific CD4+ T cell response, as measured by IFN- production, is heterogeneous amongst PBC patients being directed against various pools clearly suggesting the presence of several dominant PDC-E2 epitopes. Mo1440 CONCOMITANT AUTOIMMUNE DISEASES IN PATIENTS WITH PRIMARY SCLEROSING CHOLANGITIS Babak Torabi Sagvand, Bo Shen Background: The association between PSC (Primary Sclerosing Cholangitis) and IBD (Inflam- matory Bowel Disease) is well-described in the literature. However, the relation between PSC and other autoimmune diseases is less studied. Aim: To investigate concomitant autoimmune diseases and their frequency in patients with PSC Methods: In this cross-sectional study, 363 consecutive patients with an established diagnosis of PSC based on magnetic resonance cholangiopancreatography, endoscopic retrograde cholangiopancreatography or liver biopsy, who have received part of their care at Cleveland Clinic Foundation, Cleveland, OH were identified. A comprehensive chart review was performed and the following data was extracted: age at the time of study, age at the time of diagnosis of PSC, gender, BMI (Body Mass Index) and the presence of other autoimmune diseases. The diagnosis of autoimmune disease was confirmed using appropriate criteria defined for each condition. For example, the diagnosis of ulcerative colitis was confirmed by reviewing colonoscopy and colon biopsy results. The frequency of each autoimmune disease was reported both in study subjects and general population (historical control, based on previous epidemiologic studies). Subsequently, patients with PSC who also had other autoimmune diseases were compared to those without other autoimmune diseases. Results: Of 363 patients with PSC, 298 patients had at least one other autoimmune disease. Compared to patients without other autoimmune diseases, these patients were younger both at the time of study (55 + 1 vs. 60 + 2, p value = .007) and at the time of diagnosis of PSC (42 + 1 vs. 50 + 2, p value = .0004). There was no difference in gender, BMI and the presence of cirrhosis between two groups. Ninety-three patients (25.6%) had at least one other autoimmune disease asides from IBD and PSC. The second most frequent concomitant autoimmune disease in study subjects was autoimmune hepatitis, followed by Grave's disease, Hashimoto's thyroiditis, rheumatoid arthritis, antiphos- pholipid syndrome, Sjögren's disease, Celiac disease, idiopathic thrombocytopenic purpura and systemic lupus erythematosus, etc. Table 1 shows concomitant autoimmune diseases, their frequency in study subjects and their estimated prevalence in the United States adults based on previous epidemiologic studies. Conclusion: PSC might be associated with an increased frequency of other autoimmune diseases. This association is not confined to IBD. Autoimmune hepatitis is the second most frequent concomitant autoimmune disease in patients with PSC followed by Grave's disease, Hashimoto's thyroiditis and rheumatoid arthritis. Further case-control studies are required to assess these potential associations. S-1207 AASLD Abstracts Table 1 - Concomitant autoimmune diseases, their frequency in study subjects and their prevalence in the United States adults *Estimated prevalence of each condition was primarily obtained from the most recent CDC (Center of Disease Control) report. **No valid report available Mo1441 INTRAHEPATIC CHOLESTASIS OF PREGNANCY, EPIDEMIOLOGY AND DEMOGRAPHY OVER A 10-YEAR PERIOD IN ICELAND Thora S. Gudmundsdottir, Einar Björnsson, Thora Steingrimsdottir Background: Intrahepatic cholestasis of pregnancy (ICP) is a liver disease unique to preg- nancy. The frequency of ICP in Europe varies from 0.5%-1.5% but the highest frequency world-wide has been found in Chile (4-10%). Seasonal variation in the diagnosis of ICP has been described with fewer cases during the summer months. Proposed reasons are selenium and vitamin D insufficiency. The main laboratory abnormality is raised bile acids (BA). Complications can arise for the foetus, the most severe ones being sudden intrauterine death and preterm birth. Treatment consists mainly of ursodeoxycholic acid (UDCA). Very few population based studies on ICP exist. We aimed to determine the incidence, management and pregnancy outcomes for women with ICP in Iceland over a 10-year period. Methods: The study was retrospective and population-based. The cohort consisted of all pregnant women diagnosed with raised bile acids over a 10-year period 2007 - 2016 in Iceland (1124 pregnancies, 1028 women). ICP was diagnosed when BA levels were > 15 μmol/L. Data on maternal demographics, medical history, biochemical parameters, treatment and pregnancy outcomes was retrieved from hospital records from all nine hospitals in the country. A control group consisted of women matched for age, date of birth and parity. A comparison was also made with data from the National Birth Registry. Results: The incidence of ICP over the 10-year period was 2.7%. The incidence of ICP in multiple pregnancies was considerably higher, 7.8% (p=0.016). Overall 39% of the diagnosis of ICP occurred in the winter months (December-March) compared to only 26% during the summer months (June- September), p < 0.001. There was no significant difference in age. Ursodeoxycholic acid (UDCA) was prescribed in 37% of cases with the average gestational length, at first prescrip- tion, 32.2 weeks and the average dose at 1131 mg/day. Dexamethasone was added to UDCA in severe disease (BA < 55μmol/L) in 6.2% of cases. Preterm births (<37 weeks) occurred in 11.3% of the pregnancies, compared to the national incidence of 5.5% (p = 0.004). The rate of induction of labor was higher in the study group at 50% compared to a national incidence of 29% (p < 0,001). Conclusions: The incidence of ICP was higher in Iceland than in the rest of Europe. The rate of diagnosis of ICP was significantly higher during the winter months. The high incidence of ICP in multiple pregnancies most likely represents the importance of hormones in the pathogenesis of ICP. The rate of preterm birth and induction of labor was significantly higher in the ICP group. AASLD Abstracts