Automated harvesting and 2-step purification of unclarified mammalian cell-culture broths containing antibodies.

Therapeutic monoclonal antibodies represent one of the fastest growing segments in the pharmaceutical market. The growth of the segment has necessitated development of new efficient and cost saving platforms for the preparation and analysis of early candidates for faster and better antibody selection and characterization. We report on a new integrated platform for automated harvesting of whole unclarified cell-culture broths, followed by in-line tandem affinity-capture, pH neutralization and size-exclusion chromatography of recombinant antibodies expressed transiently in mammalian human embryonic kidney 293T-cells at the 1-L scale. The system consists of two bench-top chromatography instruments connected to a central unit with eight disposable filtration devices used for loading and filtering the cell cultures. The staggered parallel multi-step configuration of the system allows unattended processing of eight samples in less than 24h. The system was validated with a random panel of 45 whole-cell culture broths containing recombinant antibodies in the early profiling phase. The results showed that the overall performances of the preparative automated system were higher compared to the conventional downstream process including manual harvesting and purification. The mean recovery of purified material from the culture-broth was 66.7%, representing a 20% increase compared to that of the manual process. Moreover, the automated process reduced by 3-fold the amount of residual aggregates in the purified antibody fractions, indicating that the automated system allows the cost-efficient and timely preparation of antibodies in the 20-200mg range, and covers the requirements for early in vitro and in vivo profiling and formulation of these drug candidates.

Antimicrobial peptides in the duodenum at the acute and convalescent stages in patients with diarrhea due to Vibrio cholerae O1 or enterotoxigenic Escherichia coli infection.

Patients with acute watery diarrhea caused by Vibrio cholerae O1 or enterotoxigenic Escherichia coli (ETEC) were analyzed for innate immune factors produced by the epithelium during the disease process. Duodenal biopsies were obtained from study participants at the acute (day 2) and convalescent (day 21) stages of disease. Levels of α-defensin (HD-5 and -6), ß-defensin (hBD-1-4), and cathelicidin (LL-37) mRNAs were determined by real-time qRT-PCR. hBD-2, HD-5, LL-37 peptides were analyzed in duodenal epithelium by immunomorphometry. Concentration of hBD-2 in stool was determined by ELISA. Specimens from healthy controls were also analyzed. hBD-2 mRNA levels were significantly increased at acute stage of diarrhea; hBD-2 peptide was detected in fecal specimens but barely in duodenal epithelium at acute stage. Immunomorphometry analysis showed that Paneth cells contain significantly higher amounts of HD-5 pre/propeptide at convalescence (P<0.01) and in healthy controls (P<0.001) compared to acute stage, LL-37 peptide levels also decreased at acute stage while mRNA levels remained unchanged. mRNA expression levels of the other antimicrobial peptides remained unchanged with higher levels of α-defensins than ß-defensins. V. cholerae induced an innate immune response at the acute stage of disease characterized by increased expression of hBD-2, and continued expression of hBD-1, HD-5-6, and LL-37.

Health check-ups and family screening allow detection of hereditary hemochromatosis with less advanced liver fibrosis and survival comparable with the general population.

OBJECTIVE: The information concerning the morbidity and mortality of hereditary hemochromatosis is based primarily on clinical cohorts of symptomatic patients. The major aim of this study was to analyze the long-term prognosis for Swedish patients with this condition, with respect to both clinical features and survival, in relation to the route by which the disease was detected. PATIENTS AND METHODS: 373 patients with hemochromatosis detected through routine health check-ups (n = 153), family screening (n = 44), symptoms of arthralgia (n = 23), investigation of other diseases/symptoms (n = 108) or signs of liver disease (n = 45) were monitored for a mean period of 11.9 ± 5.8 years. The degree of liver fibrosis and survival were analyzed. RESULTS: Overall survival among these patients was not significantly different from that of a matched normal population. The patients diagnosed through health check-ups and family screening were detected at an earlier age and had the highest rate of survival. Liver biopsy at the time of diagnosis revealed cirrhosis in 9% of those detected through the health check-ups and 5% in the case of family screening, compared with 13% for the group with arthralgia, 17% for other diseases/symptoms and 42% for liver disease. CONCLUSION: Health check-ups and family screening allow detection of hereditary hemochromatosis at an earlier age and with less advanced liver fibrosis, although a few of these patients have already developed cirrhosis. Our study indicates that iron indices should be included in health check-ups, and if abnormal, should lead to further investigation.

The relationship between the val158met catechol-O-methyltransferase (COMT) polymorphism and irritable bowel syndrome.

BACKGROUND: The catechol-O-methyltransferase (COMT) enzyme has a key function in the degradation of catecholamines and a functional polymorphism is val158met. The val/val genotype results in a three to fourfold higher enzymatic activity compared with the met/met genotype, with the val/met genotype exhibiting intermediate activity. Since pain syndromes as well as anxiety and depression are associated to low and high COMT activity respectively and these conditions are all associated with irritable bowel syndrome (IBS) we wanted for the first time to explore the relationship between the polymorphism and IBS. METHODOLOGY/PRINCIPAL FINDINGS: 867 subjects (445 women) representative of the general population and 70 consecutively sampled patients with IBS (61 women) were genotyped for the val158met polymorphism and the IBS patients filled out the Hospital-Anxiety-and-Depression-Scale (HADS) questionnaire, and an IBS symptom diary. RESULTS: There was a significantly higher occurrence of the val/val genotype in patients compared with controls (30% vs 20%; Chi(2) (1) 3.98; p = 0.046) and a trend toward a lower occurrence of the val/met genotype in IBS patients compared with controls (39% vs 49%; Chi(2) (1) 2.89; p = 0.089). Within the IBS patients the val/val carriers exhibited significantly increased bowel frequency (2.6 vs 1.8 stools per day; Chi(2) (1) 5.3; p = 0.03) and a smaller proportion of stools with incomplete defecation (41% vs 68%; Chi(2) (1) 4.3; p = 0.04) compared with the rest (val/met+met/met carriers). The val/val carriers also showed a trend for a smaller proportion of hard stools (0% vs 15%; Chi(2) (1) 3.2; p = 0.08) and a higher frequency of postprandial defecation (26% vs 21%; Chi(2) (1) 3.0; p = 0.08). CONCLUSIONS/SIGNIFICANCE: In this study we found an association between the val/val genotype of the val158met COMT gene and IBS as well as to specific IBS related bowel pattern in IBS patients.

Characteristics and long-term outcome of patients with autoimmune hepatitis related to the initial treatment response.

OBJECTIVES: Autoimmune hepatitis (AIH) is a liver disease which, if untreated, may lead to liver cirrhosis and hepatic failure. Limited data exist regarding factors predicting the long-term outcome. The aims of this study were to investigate symptoms at presentation, prognostic features, management and treatment in relation to long-term outcome of AIH. MATERIAL AND METHODS: A cohort of 473 Swedish patients with AIH was characterized regarding initial symptoms and signs, factors predicting death and future need for liver transplantation. Survival and causes of death were retrieved from Swedish national registers. RESULTS: At diagnosis, fatigue was a predominant symptom (69%), 47% of the patients were jaundiced and 30% had liver cirrhosis. Another 10% developed cirrhosis during follow-up. Markedly elevated alanine aminotransferase levels at presentation were correlated with a better outcome. A high international normalized ratio (INR) at diagnosis was the only risk factor predicting a need for later liver transplantation. Histological cirrhosis, decompensation and non-response to initial treatment were all factors that correlated with a worse outcome. Overall life expectancy was generally favourable. However, most deaths were liver-related, e.g. liver failure, shock and gastrointestinal bleeding. CONCLUSIONS: Cirrhosis at diagnosis, a non-response to initial immune-suppressive treatment or elevated INR values were associated with worse outcome and a need for later liver transplantation. In contrast, an acute hepatitis-like onset with intact synthetic capacity indicated a good response to treatment and favourable long-term prognosis. Lifetime maintenance therapy is most often required.

Transitions between variant forms of primary biliary cirrhosis during long-term follow-up.

BACKGROUND: Conditions exhibiting features of two different autoimmune liver diseases are designated overlap syndromes. Variant forms display some, but not all, characteristics of a distinct autoimmune liver disease. We describe transitions over time between variant forms of PBC, i.e. AMA-negative PBC, autoimmune hepatitis (AIH)-PBC overlap and autoimmune cholangitis (AIC) in a large cohort of PBC patients in Sweden. METHODS: We retrieved all patients with variant forms of PBC in six university hospitals in Sweden, covering 60% of the Swedish population. The diagnosis of PBC and its variants was based on laboratory findings and compatible histological features. The revised autoimmune hepatitis scoring system proposed by the International Autoimmune Hepatitis Group was used to establish the diagnosis of AIH. RESULTS: In a population of 800 patients with PBC, we identified 35 (5%) variant forms; 25 patients with AIH-PBC overlap, 8 with AIC and 2 with AMA-negative PBC at the time of our study. The initial diagnoses were PBC (3 patients), AIH (3), AIH-PBC overlap (16), AIC (8) and AMA-negative PBC with (1) or without (4) concomitant AIH. The median follow-up was 125 (41-360) months. Immunosuppression and ursodeoxycholic acid induced a complete or good regression of increased aminotransferases in about half of the patients who were given one or both of these treatments. CONCLUSIONS: Variant forms of PBC are seen in approximately 5% of PBC patients in Sweden. Transition between different forms may occur, emphasizing the value of repeat biopsies, but established overlapping AIH-PBC seems to be stable over time.

High prevalence of small duct primary sclerosing cholangitis among patients with overlapping autoimmune hepatitis and primary sclerosing cholangitis.

BACKGROUND: Overlap syndrome is a term used for overlapping features of autoimmune hepatitis and primary sclerosing cholangitis or primary biliary cirrhosis and for autoimmune cholangitis. We describe a high prevalence of small duct primary sclerosing cholangitis among patients with overlapping autoimmune hepatitis and primary sclerosing cholangitis. METHODS: We sought to retrieve all patients with overlap syndrome between primary sclerosing cholangitis and autoimmune hepatitis in six university hospitals in Sweden. The revised autoimmune hepatitis scoring system proposed by the International Autoimmune Hepatitis Group was used to establish the diagnosis autoimmune hepatitis. Endoscopic retrograde cholangiography and/or magnetic resonance cholangiography were used to separate the primary sclerosing cholangitis cases diagnosed through liver biopsy into small and large primary sclerosing cholangitis. A histological diagnosis compatible with both autoimmune hepatitis and primary sclerosing cholangitis was required for inclusion. RESULTS: 26 patients fulfilled our criteria for histological overlap of autoimmune hepatitis and primary sclerosing cholangitis, 7 (27%) of which had small duct primary sclerosing cholangitis. The reliability of the diagnosis small duct primary sclerosing cholangitis was supported by a very close similarity between small and large duct primary sclerosing cholangitis patients in clinical and laboratory data, and by a poor response to immunosuppressive therapy in the small duct primary sclerosing cholangitis patients. Patients with large duct overlap syndrome had a good response to immunosuppressive therapy. In both groups, our limited experience from ursodeoxycholic acid was largely poor. CONCLUSIONS: Small duct primary sclerosing cholangitis is prevalent in the overlap syndrome between autoimmune hepatitis and primary sclerosing cholangitis.

Budd-Chiari syndrome in Sweden: epidemiology, clinical characteristics and survival - an 18-year experience.

BACKGROUND: The exact incidence and prevalence of Budd-Chiari syndrome (BCS) is unknown in the general population. Published reports differ in terms of the clinical characteristics, effects of therapy and survival. AIMS: To investigate the epidemiology, clinical presentation and survival in patients with BCS. METHODS: Retrospective multicentre study in Sweden reviewing the medical records of all patients with BCS 1986-2003, identified from the computerised diagnosis database of 11 hospitals, including all university hospitals and liver transplantation centres. RESULTS: Forty-three patients with BCS were identified, of whom nine (21%) had concomitant portal vein thrombosis. The mean age-standardised incidence and prevalence rates in 1990-2001 were calculated to be 0.8 per million per year and 1.4 per million inhabitants respectively. Myeloproliferative disorders (38%), thrombophilic factors (31%) and oral contraceptives (30%) were common aetiological factors. Two or more risk factors were present in 44%. In 23%, no risk factor was evident. The median follow-up time was 2.7 years. Seventy-two percent were on anticoagulant therapy during follow-up. Transjugular intrahepatic portosystemic shunting, surgical shunting procedures and liver transplantation were performed in 4, 6 and 18 patients respectively. Nineteen patients died. The overall transplantation-free survival at 1, 5 and 10 years was 47, 28 and 17% respectively. CONCLUSIONS: Budd-Chiari syndrome is a rare disorder; the mean age-standardised incidence and prevalence rates in Sweden in 1990-2001 were calculated to be 0.8 per million per year and 1.4 per million inhabitants respectively. The presence of a myeloproliferative disorder was a common aetiological factor in our cohort and about half of the patients had a multifactorial aetiology. The transplantation-free survival was poor.

Hepatic and extrahepatic malignancies in autoimmune hepatitis. A long-term follow-up in 473 Swedish patients.

BACKGROUND/AIMS: Autoimmune Hepatitis (AIH) is a liver disease which may lead to liver cirrhosis. Cirrhosis is a well-known risk factor for hepatocellular cancer. Lymphoma is a disease, where immune modulating drugs as well as the autoimmune disease itself may contribute to the elevated risk. The aim was to investigate the risks of malignancies in a large cohort of AIH patients. METHODS: Four hundred and seventy-three patients with AIH were matched to the Swedish national cancer register as well as to the death cause register. RESULTS: We found an overall higher risk of malignancies in the cohort of AIH patients from the date of diagnosis with a SIR of 1.51 (95% CI 1.10-2.03). SIR in the subpopulation of well defined catchment areas and complete case finding was 23.28 (95% CI 7.5-54.34) for HCC. Lymphomas were found a SIR of 13.09 (95% CI 4.22-30.56). CONCLUSIONS: There was an overall increased risk of malignancies in a cohort of AIH patients, which manly was caused by hepatobiliary cancers. However, the true risk of HCC in an AIH cirrhotic cohort has yet to be investigated. A significantly higher risk of lymphomas was also found, but no clear cut association to the use of immune modulators.

Increased risk of primary sclerosing cholangitis and ulcerative colitis in first-degree relatives of patients with primary sclerosing cholangitis.

BACKGROUND & AIMS: The importance of genetic factors for the development of primary sclerosing cholangitis (PSC) is incompletely understood. This study assessed the risk of PSC and inflammatory bowel disease (IBD) among first-degree relatives of patients with PSC, compared with the first-degree relatives of a cohort without PSC. METHODS: Subjects from the national Swedish cohort of PSC patients (n = 678) were matched for date of birth, sex, and region to up to 10 subjects without a diagnosis of PSC (n = 6347). Linkage through general population registers identified first-degree relatives of subjects in both the PSC and comparison cohorts (n = 34,092). Diagnoses among first-degree relatives were identified by using the Inpatient Register. RESULTS: The risk of cholangitis was statistically significantly increased in offspring, siblings, and parents of the PSC patient cohort, compared with relatives of the comparison cohort, with the hazard ratios and 95% confidence intervals, 11.5 (1.6-84.4), 11.1 (3.3-37.8), and 2.3 (0.9-6.1), respectively. The hazard ratios for ulcerative colitis (UC) among first-degree relatives of all PSC patients was 3.3 (2.3-4.9) and for Crohn's disease 1.4 (0.8-2.5). The risk of UC for relatives of PSC patients without IBD was also increased, 7.4 (2.9-18.9). CONCLUSIONS: First-degree relatives of patients with PSC run an increased risk of PSC, indicating the importance of genetic factors in the etiology of PSC. First-degree relatives of PSC patients without IBD are also at an increased risk of UC, which might indicate shared genetic susceptibility factors for PSC and UC.

Epidemiology and the initial presentation of autoimmune hepatitis in Sweden: a nationwide study.

OBJECTIVE: Autoimmune hepatitis (AIH) is a chronic liver disease, which if untreated can lead to cirrhosis and hepatic failure. The aim of the study was to investigate the incidence, prevalence, diagnostic tradition and clinical initial presentation of AIH. MATERIAL AND METHODS: Analyses were performed in 473 patients identified as having probable or definite AIH. RESULTS: The incidence of AIH was 0.85/100,000 (95% CI 0.69-1.01) inhabitants, which is somewhat lower than reported previously. The point prevalence amounted to 10.7/100,000 (95% CI 8.8-13.1), and 76% of the cases were females. The age-related incidence curve was bimodal but men were found to have only one incidence peak in the late teens, whereas women had a peak after menopause. AIH was presented as a spectrum of clinical settings from detected "en passant" to acute liver failure. Almost 30% of patients already had liver cirrhosis at diagnosis. Autoantibodies indicative of AIH type 1 were found in 79% of cases. Other concomitant autoimmune diseases were frequently found (49%). CONCLUSIONS: The incidence and prevalence figures confirm that AIH is a fairly uncommon disease in the Swedish population. Symptoms at presentation were unspecific, but almost half of the patients were jaundiced, with around 30% having liver cirrhosis. The majority of Swedish AIH patients had AIH type 1.

Diet in the aetiology of ulcerative colitis: a European prospective cohort study.

BACKGROUND/AIMS: The causes of ulcerative colitis are unknown, although it is plausible that dietary factors are involved. Case-control studies of diet and ulcerative colitis are subject to recall biases. The aim of this study was to examine the prospective relationship between the intake of nutrients and the development of ulcerative colitis in a cohort study. METHODS: The study population was 260,686 men and women aged 20-80 years, participating in a large European prospective cohort study (EPIC). Participants were residents in the UK, Sweden, Denmark, Germany or Italy. Information on diet was supplied and the subjects were followed up for the development of ulcerative colitis. Each incident case was matched with four controls and dietary variables were divided into quartiles. RESULTS: A total of 139 subjects with incident ulcerative colitis were identified. No dietary associations were detected, apart from a marginally significant positive association with an increasing percentage intake of energy from total polyunsaturated fatty acids (trend across quartiles OR = 1.19 (95% CI = 0.99-1.43) p = 0.07). CONCLUSIONS: No associations between ulcerative colitis and diet were detected, apart from a possible increased risk with a higher total polyunsaturated fatty acid intake. A biological mechanism exists in that polyunsaturated fatty acids are metabolised to pro-inflammatory mediators.

Gastrointestinal symptoms are associated with hypothalamic-pituitary-adrenal axis suppression in healthy individuals.

OBJECTIVE: The brain-gut axis has been proposed to influence symptoms in irritable bowel syndrome (IBS). In animal studies corticotropin-releasing hormone (CRH) challenge has been associated with decreased upper gastrointestinal motility and increased colonic motility. The purpose of this study was to investigate the association between gastrointestinal symptoms and the effect of CRH on the hypothalamic-pituitary-adrenal (HPA) axis using a weight-adjusted low-dose dexamethasone test in a group of healthy individuals (n = 157). MATERIAL AND METHODS: Pre- and post-dexamethasone morning serum cortisol was analysed. All participants completed questionnaires regarding symptoms of IBS (GSRS-IBS (Gastrointestinal Symptom Rating Scale-IBS) and symptoms of anxiety and depression (HADS (Hospital Anxiety and Depression Scale)). After exclusions, 124 subjects were available for analysis (F/M: 60/64, mean age 55.8 years, SD 15.4, range 21-80 years). RESULTS: A positive correlation was found between the GSRS-IBS score and HADS score (rs =0.36; p <0.001). There was no linear correlation between either pre- (rs = 0.145; p = 0.11) or post-dexamethasone cortisol levels (rs =0.087; p =0.337) and GSRS-IBS scores. By subgrouping the subjects at the lower and higher 25th percentiles of their post-dexamethasone morning cortisol levels, we found a trend towards a higher GSRS-IBS score (median 7.0 versus 5.0; p =0.069) (multivariate adjusted OR 2.6; CI 0.80-8.3) and a significantly higher diarrhoea score (median 2 versus 0; p = 0.021) (multivariate adjusted OR 5.7; CI 1.5-22), and a higher early satiety score (p=0.008) (multivariate adjusted OR 6.7; CI: 1.9-23) in the subjects with high post-dexamethasone cortisol levels (low HPA suppression) compared with the subjects with intermediate post-dexamethasone cortisol levels. Furthermore, individuals with low post-dexamethasone cortisol levels (high HPA suppression) showed a significant, higher score for diarrhoea (median 2.0 versus 0; p =0.010) (multivariate adjusted OR 6.1; CI 1.8-20) and early satiety (p=0.076) (multivariate adjusted OR 3.2; CI 1.0-10) compared with those with intermediate cortisol levels. CONCLUSIONS: A trend toward a non-linear relationship between IBS-like symptoms and post-dexamethasone cortisol levels was observed in healthy individuals, with significantly more symptoms of diarrhoea and early satiety in individuals with high or low post-dexamethasone cortisol levels in comparison with those with intermediate post-dexamethasone cortisol levels.

Autoimmune hepatitis among fertile women: strategies during pregnancy and breastfeeding?

OBJECTIVE: In published studies there is a lack of data about the risks, management and how women with autoimmune hepatitis (AIH) decide on and are advised about pregnancy. The aim of this study was to investigate how women with AIH consider pregnancies, are advised and pharmacologically treated, as well as the outcome. MATERIAL AND METHODS: A questionnaire was mailed to 128 women with AIH diagnosed during their fertile period and data from the Swedish National Birth Register was also used for matched controls. RESULTS: There was an 83% response rate to the questionnaires. Sixty-three pregnancies were reported by 35 women. 48% did not consult their doctors before getting pregnant. More than half of the women reduced or stopped the immune suppression during pregnancy or breastfeeding. Some women were advised to abstain from pregnancy or even to have an abortion. Caesarean sections were performed more frequently in the AIH group (16% compared with 6.5% in the control group p<0.01). There were no significant differences in the number of stillborn infants or infants with malformations. However, 30% of the patients experienced flare-up after delivery. CONCLUSIONS: In general, the outcome of pregnancy in women with AIH seems to be good. Current pharmacological treatment appears to be safe, including azathioprine during pregnancy and lactation. After delivery an active preparedness to increase pharmacotherapy should be considered.

Beta-defensin production by human colonic plasma cells: a new look at plasma cells in ulcerative colitis.

BACKGROUND: Previously, we showed that colonic epithelium of ulcerative colitis (UC) patients expresses increased levels of mRNA for 3 antimicrobial peptides, human beta-defensin 2 (hBD-2), hBD-3, and hBD-4 compared to controls. METHODS: Human colon mucosa was analyzed using double immunofluorescence staining, in situ hybridization, immunoelectron microscopy, and quantitative real-time reverse-transcriptase polymerase chain reaction (qRT-PCR) with specific antibodies and probes in the respective assays. RESULTS: We demonstrate that lamina propria in colon from UC patients, Crohn's colitis patients, and controls contain cells that express hBD-2. These cells were identified as mature plasma cells by the highly specific CD138 marker, by their prominent IgA or IgG expression, and by their ultrastructural characteristics. By immunoelectron microscopy it was furthermore shown that the hBD-2 peptide was expressed in rough endoplasmic reticulum, the Golgi complex, and cytoplasmic vesicles, reflecting consecutive steps of synthesis and transport for secretion. Plasma cells were 2-3 times more abundant in UC colon than in control colon and Crohn's colitis. Moreover, plasma cells in UC colon expressed hBD-3 and hBD-4 mRNA. Additionally, hBD-2 mRNA expression was demonstrated in 3 out of 4 well-characterized plasma cell lines. CONCLUSIONS: Mature colonic plasma cells can express multiple beta-defensins. In UC, defensin production by plasma cells is probably clinically relevant since plasma cells accumulate in large numbers between the distorted crypts and muscularis mucosae, first focally than diffusely, so as to protect against microbial attack.