Genetic determinants of type 1 diabetes in individuals with weak evidence of islet autoimmunity at disease onset

AIMS/HYPOTHESIS

Islet autoantibodies (AAbs) are detected in >90% of individuals with clinically suspected type 1 diabetes at disease onset. A single AAb, sometimes at low titre, is often detected in some individuals, making their diagnosis uncertain. Type 1 diabetes genetic risk scores (GRS) are a useful tool for discriminating polygenic autoimmune type 1 diabetes from other types of diabetes, particularly the monogenic forms, but testing is not routinely performed in the clinic. Here, we used a type 1 diabetes GRS to screen for monogenic diabetes in individuals with weak evidence of autoimmunity, i.e. with a single AAb at disease onset.

METHODS

In a pilot study, we genetically screened 142 individuals with suspected type 1 diabetes, 42 of whom were AAb-negative, 27 of whom had a single AAb (single AAb-positive) and 73 of whom had multiple AAbs (multiple AAb-positive) at disease onset. Next-generation sequencing (NGS) was performed in 41 AAb-negative participants, 26 single AAb-positive participants and 60 multiple AAb-positive participants using an analysis pipeline of more than 200 diabetes-associated genes.

RESULTS

The type 1 diabetes GRS was significantly lower in AAb-negative individuals than in those with a single and multiple AAbs. Pathogenetic class 4/5 variants in MODY or monogenic diabetes genes were identified in 15/41 (36.6%) AAb-negative individuals, while class 3 variants of unknown significance were identified in 17/41 (41.5%). Residual C-peptide levels at diagnosis were higher in individuals with mutations compared to those without pathogenetic variants. Class 3 variants of unknown significance were found in 11/26 (42.3%) single AAb-positive individuals, and pathogenetic class 4/5 variants were present in 2/26 (7.7%) single AAb-positive individuals. No pathogenetic class 4/5 variants were identified in multiple AAb-positive individuals, but class 3 variants of unknown significance were identified in 19/60 (31.7%) patients. Several patients across the three groups had more than one class 3 variant.

CONCLUSIONS/INTERPRETATION

These findings provide insights into the genetic makeup of patients who show weak evidence of autoimmunity at disease onset. Absence of islet AAbs or the presence of a single AAb together with a low type 1 diabetes GRS may be indicative of a monogenic form of diabetes, and use of NGS may improve the accuracy of diagnosis.

Adjusting insulin doses in patients with type 1 diabetes who use insulin pump and continuous glucose monitoring: Variations among countries and physicians

AIMS

To evaluate physicians' adjustments of insulin pump settings based on continuous glucose monitoring (CGM) for patients with type 1 diabetes and to compare these to automated insulin dose adjustments.

METHODS

A total of 26 physicians from 16 centres in Europe, Israel and South America participated in the study. All were asked to adjust insulin dosing based on insulin pump, CGM and glucometer downloads of 15 patients (mean age 16.2 ± 4.3 years, six female, mean glycated haemoglobin 8.3 ± 0.9% [66.8 ± 7.3 mmol/mol]) gathered over a 3-week period. Recommendations were compared for the relative changes in the basal, carbohydrate to insulin ratio (CR) and correction factor (CF) plans among physicians and among centres and also between the physicians and an automated algorithm, the Advisor Pro (DreaMed Diabetes Ltd, Petah Tikva, Israel). Study endpoints were the percentage of comparison points for which there was full agreement on the trend of insulin dose adjustments (same trend), partial agreement (increase/decrease vs no change) and full disagreement (opposite trend).

RESULTS

The percentages for full agreement between physicians on the trend of insulin adjustments of the basal, CR and CF plans were 41 ± 9%, 45 ± 11% and 45.5 ± 13%, and for complete disagreement they were 12 ± 7%, 9.5 ± 7% and 10 ± 8%, respectively. Significantly similar results were found between the physicians and the automated algorithm. The algorithm magnitude of insulin dose change was at least equal to or less than that proposed by the physicians.

CONCLUSIONS

Physicians provide different insulin dose recommendations based on the same datasets. The automated advice of the Advisor Pro did not differ significantly from the advice given by the physicians in the direction or magnitude of the insulin dosing.

Metabolic control and complications in Italian people with diabetes treated with continuous subcutaneous insulin infusion

BACKGROUND AND AIM

The objective of this cross-sectional study was to evaluate the degree of glycaemic control and the frequency of diabetic complications in Italian people with diabetes who were treated with continuous subcutaneous insulin infusion (CSII).

METHODS AND RESULTS

Questionnaires investigating the organisation of diabetes care centres, individuals' clinical and metabolic features and pump technology and its management were sent to adult and paediatric diabetes centres that use CSII for treatment in Italy. Information on standard clinical variables, demographic data and acute and chronic diabetic complications was derived from local clinical management systems. The sample consisted of 6623 people with diabetes, which was obtained from 93 centres. Of them, 98.8% had type 1 diabetes mellitus, 57.2% were female, 64% used a conventional insulin pump and 36% used a sensor-augmented insulin pump. The median glycated haemoglobin (HbA_1c) level was 60 mmol/mol (7.6%). The HbA_1c target (i.e. <58 mmol/mol for age <18 years and <53 mmol/mol for age >18 years) was achieved in 43.4% of paediatric and 23% of adult participants. Factors such as advanced pump functions, higher rate of sensor use, pregnancy in the year before the study and longer duration of diabetes were associated with lower HbA_1c levels. The most common chronic complications occurring in diabetes were retinopathy, microalbuminuria and hypertension. In the year before the study, 5% of participants reported ≥1 episode of severe hypoglycaemic (SH) episodes (SH) and 2.6% reported ≥1 episode of ketoacidosis.

CONCLUSIONS

Advanced personal skills and use of sensor-based pump are associated with better metabolic control outcomes in Italian people with diabetes who were treated with CSII. The reduction in SH episodes confirms the positive effect of CSII on hypoglycaemia.

CLINICAL TRIAL REGISTRATION NUMBER

NCT 02620917 (ClinicalTrials.gov).

Necrobiosis Lipoidica Diabeticorum: A pediatric case report

Introduction: Necrobiosis lipoidica (NL) is a rare chronic granulomatous dermatitis that usually appears in the lower extremities. It affects about 0.3–1.2% of diabetic patients, the majority of whom have type 1 diabetes. The etiology and pathogenesis of this disorder are still unclear. NL is characterized by skin rash that usually affects the shins. The average onset is 30 years, with females being affected more commonly. There are very few reported cases of necrobiosis lipoidica in children.

Case report: We report a case of a 16 year old girl affected by type 1 diabetes mellitus (15 years disease duration) who developed an erythematous nodular rash on the lower extremities and interscapular area. In the suspect of necrobiosis lipoidica, a skin biopsy was performed (lower extremities and interscapular area). The microscopic evaluation of the pretibial lesions was suggestive of necrobiosis lipoidica. The smaller lesions in the interscapular area showed signs of perivascular dermatitis which could be consistent with early stages of necrobiosis lipoidica. Local treatment with tacrolimus determined a progressive improvement of the lesions.

Conclusion: In patients with T1DM, diagnosis of NL of the lower legs is usually unequivocal. However, diagnosis may be more challenging in the presence of lesions with recent onset and/or atypical clinical presentation and unusual site. In these cases, NL must always be taken in consideration in order to avoid misdiagnosis, wrong/late treatment decisions and progression to ulceration.

Successful control of an outbreak of colonization by Klebsiella pneumoniae carbapenemase-producing K. pneumoniae sequence type 258 in a neonatal intensive care unit, Italy

This article reports an outbreak of colonization by Klebsiella pneumoniae carbapenemase-producing K. pneumoniae (KPC-Kp) sequence type (ST) 258 in a neonatal intensive care unit (NICU) in Palermo, Italy. KPC-Kp ST258 was detected by an active surveillance culture programme. Between 18th September and 14th November 2012, KPC-Kp was isolated from 10 out of 54 neonates admitted in the outbreak period. No cases of infection were recorded. Male sex was associated with colonization, whereas administration of ampicillin- sulbactam plus gentamicin was protective. Infection control interventions interrupted the spread of KPC-Kp without the need to close the NICU to new admissions.

Future Perspectives in Glucose Monitoring Sensors

The prevalence of diabetes is increasing. improved glucose control is fundamental to reduce both long-term micro- and macrovascular complications and short-term complications, such as diabetic ketoacidosis and severe hypoglycemia. Frequent blood glucose monitoring is an essential part of diabetes management. However, almost all available blood glucose monitoring devices are invasive. This determines a reduced patient compliance, which in turn reflects negatively on glucose control. Therefore, there is a need to develop noninvasive glucose monitoring devices that will reduce the need of invasive procedures, thus increasing patient compliance and consequently improving quality of life and health of patients with diabetes.

Future Perspectives in Glucose Monitoring Sensors

The prevalence of diabetes is increasing. Improved glucose control is fundamental to reduce both long-term micro- and macrovascular complications and short-term complications, such as diabetic ketoacidosis and severe hypoglycemia. Frequent blood glucose monitoring is an essential part of diabetes management. However, almost all available blood glucose monitoring devices are invasive. This determines a reduced patient compliance, which in turn reflects negatively on glucose control. Therefore, there is a need to develop noninvasive glucose monitoring devices that will reduce the need of invasive procedures, thus increasing patient compliance and consequently improving quality of life and health of patients with diabetes.

Sensor-augmented pump therapy in very young children with type 1 diabetes: an efficacy and feasibility observational study

BACKGROUND

Efficacy and feasibility of sensor-augmented pump (SAP) therapy were evaluated in very young children with type 1 diabetes (T1D).

SUBJECTS AND METHODS

SAP (Dexcom [San Diego, CA] Seven Plus™ usage combined with insulin pump) therapy was retrospectively evaluated in 28 children (15 boys) younger than 7 years (mean age, 5.8 ± 1.2 years; range, 3-7 years), with T1D. Glycosylated hemoglobin (HbA1c) was evaluated at baseline and at the end of the study, as were efficacy and feasibility of the system, using a rating scale (with 3 being the most positive).

RESULTS

SAP has been used for at least 6 months by 85% of patients, with an overall good satisfaction (92%). The greatest perceived benefit was the reduced fear of hypoglycemia (score of 3, 81%). HbA1c significantly improved only in patients with baseline HbA1c >7.5% (P = 0.026).

CONCLUSIONS

SAP therapy is effective and feasible in preschool children with T1D. In patients with high HbA1c at baseline it provide a 0.9% decrease, sustained for at least 6 months.

Ongoing spread of colistin-resistant Klebsiella pneumoniae in different wards of an acute general hospital, Italy, June to December 2011

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Ongoing spread of colistin-resistant Klebsiella pneumoniae in different wards of an acute general hospital, Italy, June to December 2011

We describe polyclonal spread of colistin-resistant Klebsiella pneumoniae in an acute general hospital in Italy. Between June and December 2011, 58 colistin-resistant K. pneumoniae isolates were recovered from 28 patients admitted to different wards, but mainly in the intensive care units. All isolates were tested for drug susceptibility and the presence of beta-lactamase (bla) genes. Clonality was investigated by repetitive extragenic palindromic (rep)-PCR and multilocus sequence typing (MLST). Fifty-two isolates had minimum inhibitory concentrations (MICs) for colistin of 6-128 mg/L, carried bla(KPC3) and were attributed to sequence type ST258. The remaining six isolates were susceptible to carbapenems, exhibited MICs for colistin of 3-32 mg/L, and belonged to two different types, ST15 and ST273. Rep-PCR included all isolates in three clusters, one containing all ST258 KPC-3-producing isolates and two containing ST15 and ST273 isolates.Cross-transmission containment measures and intensification of staff and environmental hygiene could not stop the outbreak. Selective pressure and horizontal transmission probably contributed to emergence and spread of three different strains of colistin-resistant K. pneumoniae in the hospital. Strict implementation of the above measures and a wider awareness of the antimicrobial resistance threat are crucial to preserve the last therapeutic options of the multidrug-resistant Gram-negative infections.

Prevalence of virulence-associated genotypes of Helicobacter pylori and correlation with severity of gastric pathology in patients from western Sicily, Italy

In a bacterium like Helicobacter pylori, which is characterized by a recombinant population structure, the associated presence of genes encoding virulence factors might be considered an expression of a selective advantage conferred to strains with certain genotypes and, therefore, a potentially useful tool for predicting the clinical outcome of infections. However, differences in the geographical and ethnic prevalence of the H. pylori virulence-associated genotypes can affect their clinical predictive value and need to be considered in advance. In this study we carried out such an evaluation in a group of patients living in Sicily, the largest and most populous island in the Mediterranean Sea. cagA, vacA, babA2, hopQ, oipA, sabA, and hopZ were the H. pylori virulence-associated genes assayed; their presence, expression status or allelic homologs were detected in H. pylori DNA samples and/or isolated strains, obtained by gastric biopsy from 90 Sicilian patients with chronic gastritis, inactive (n = 37), active (n = 26), or active with peptic ulcer (n = 27). Genotypes cagA (+), vacAs1, vacAm1, babA2 (+), and hopQ I, I/II were identified in 51.8, 80.4, 35.2, 47.3, and 67.7% of the different samples respectively. Only these genotypes were associated with each other and with the active form of chronic gastritis, irrespective of the presence of a peptic ulcer. In our isolates their prevalence was more similar to values observed in the north of Italy and France than to those observed in Spain or other Mediterranean countries that are closer and climatically more similar to western Sicily.

Assessment of hepatitis C virus-RNA clearance under combination therapy for hepatitis C virus genotype 1: performance of the transcription-mediated amplification assay

Monitoring of HCV-RNA in blood during antiviral therapy is performed mostly by commercially available reverse transcription polymerase chain reaction-based (RT-PCR) assays, with a lower detection limit of 30-50 IU/mL of HCV-RNA. Use of different tests in the pivotal trials of combination therapy has generated some discordance, in terms of predictive value of the early virological response (EVR). To evaluate whether the use of a more sensitive test, as a qualitative assay based on transcription mediated amplification (TMA) with a lower detection limit of 5-10 IU/mL of HCV-RNA, may obtain a better prediction of EVR and of the ultimate virological outcome, we retrospectively evaluated serial samples from 108 naïve patients with HCV genotype 1 chronic hepatitis, treated with pegylated alpha2b interferon plus ribavirin for 48 weeks and with a 24 weeks stopping rule. Serum samples of patients, obtained during treatment at weeks 4, 12, 24 and 48 and after treatment at week 24, were evaluated by TMA. Comparison of the RT-PCR and TMA assays for the qualitative detection of HCV-RNA showed no significant differences in performance when these tests were used at the end of the treatment period for assessing patients without an on-treatment virological response and those who eventually obtain a sustained virological response. Our results show instead that the use of TMA assay to detect HCV-RNA at 12 and 24 weeks of the combination therapy is more effective than RT-PCR in identifying patients with the highest probability of sustained HCV-RNA clearance.

Occult HBV infection and suppression of HCV replication in the early phase of combination therapy for chronic hepatitis C

BACKGROUND

Occult HBV infection in subjects with chronic hepatitis C is related to more severe disease outcome. It has been suggested that it might reduce sensitivity to antiviral treatment.

AIMS

To assess in HBsAg negative subjects with chronic hepatitis C any effect of the presence of HBV genomes in the liver on the early kinetics of HCV-RNA under PEG-IFN plus ribavirin.

PATIENTS AND METHODS

Twenty-two anti-HCV and HCV-RNA positive subjects, with biopsy-proven chronic hepatitis C (M/F 15/7; 50 +/- 8.6 years, 16 genotype 1b) were given PEG-IFN alpha 2b 1.0 microg qw plus ribavirin (800 to 1,200 mg daily according to body weight) for an intended 52 week period. Early virological response was assessed over the first 4 weeks of therapy by quantifying HCV-RNA. Occult HBV infection was assessed by testing for HBV-DNA in the liver before therapy.

RESULTS

HBV genomes were found in the liver of 7 of 22 (31.4%) patients, unrelated to anti-HBc status. Kinetics of HCV-RNA during the first 4 weeks of antiviral treatment was unaffected by occult HBV infection, both in terms of absolute reduction of viral load and of number of cases with a reduction of > or = 2 log10 on treatment.

CONCLUSIONS

Occult HBV infection does not affect the early phase of response to combination therapy. Further follow-up of patients into the maintenance phase of antiviral treatment and after stopping it will clarify if and when occult HBV has a role in reducing sustained virological response.

Are hepatitis G virus and TT virus involved in cryptogenic chronic liver disease?

BACKGROUND

Hepatitis G virus can cause chronic infection in man but the role of this agent in chronic liver disease is poorly understood. Little is known about the relation of another newly discovered agent, the TT virus, with chronic liver disease.

AIM

To investigate the rate of infection with hepatitis G virus and TT virus in patients with cryptogenic chronic liver disease.

PATIENTS

A total of 23 subjects with chronically raised alanine transaminase and a liver biopsy in whom all known causes of liver disease had been excluded, and 40 subjects with hepatitis C virus-related chronic liver disease.

METHODS

Evaluation of anti-hepatitis G virus by enzyme immunoassay. Hepatitis G virus-RNA by polymerase chain reaction with primers from the 5' NC and NS5a regions. TT virus-DNA by nested polymerase chain reaction with primers from the ORF1 region. Results. Hepatitis G virus-RNA was detected in 4 out of 23 patients with cryptogenic chronic hepatitis and in 6 out of 40 with hepatitis C virus chronic hepatitis (17.4% vs 15% p=ns). At least one marker of hepatitis G virus infection (hepatitis G virus-RNA and/or anti-hepatitis G virus, mostly mutually exclusive) was present in 6 out of 23 patients with cryptogenic hepatitis and 16 out of 40 with hepatitis C virus liver disease (26. 1% vs 40% p=ns). T virus-DNA was present in serum in 3 subjects, 1 with cryptogenic and 2 with hepatitis C virus-related chronic liver disease. Demographic and clinical features, including stage and grade of liver histology, were comparable between hepatitis G virus-infected and uninfected subjects. Severe liver damage [chronic hepatitis with fibrosis or cirrhosis) were significantly more frequent in subjects with hepatitis C virus liver disease.

CONCLUSIONS

In Southern Italy, hepatitis G virus infection is widespread among patients with chronic hepatitis, independently of parenteral risk factors. Its frequency in subjects with cryptogenic liver disease parallels that observed in hepatitis C virus chronic liver disease, thus ruling out an aetiologic role of hepatitis G virus. TT virus infection is uncommon in patients with cryptogenic or hepatitis C virus-related liver disease who do not have a history of parenteral exposure.

Biological impact of natural COOH-terminal deletions of hepatitis B virus X protein in hepatocellular carcinoma tissues

The hepatitis B virus (HBV) X protein (HBx) is a transcriptional transactivator that has been implicated in the development of HBV-related hepatocellular carcinoma. Mutations in the HBx open reading frame have been reported, but their general impact on the biological function of HBx remains unknown. To address this issue, we comparatively analyzed the structures and biological functions of HBx sequences isolated from sera and from tumor and nontumor tissues of patients with a HBV-related hepatocellular carcinoma. In addition to the HBx sequences derived from free HBV genomes, HBx from HBV integrants was also obtained from the tumor tissues by use of a HBx-Alu PCR-based approach. Sequence analysis showed that the HBx sequences derived from tumor tissues (6 of 7), particularly those isolated from HBV integrants (4 of 4), contained a deletion in the distal COOH-terminal region. Interestingly, most of the COOH-terminally truncated HBx sequences obtained from tumor tissues, in contrast to the full-length HBx isolated from the sera and nontumor tissues, lost their transcriptional activity and their inhibitory effects on cell proliferation and transformation. Importantly, although full-length HBx suppressed the focus formation induced by the cooperation of ras and myc oncogenes in primary rat embryo fibroblasts, COOH-terminally truncated HBx enhanced the transforming ability of ras and myc. Finally, by analyzing the artificial mutants, we were able to more precisely map the functional domains located at the COOH-terminal of HBx. Taken together, our results suggest a key role for the HBx COOH-terminal end in controlling cell proliferation, viability, and transformation. This study further supports the hypothesis that natural HBx mutants might be selected in tumor tissues and play a role in hepatocarcinogenesis by modifying the biological functions of HBx.

Structure and expression of Tg737, a putative tumor suppressor gene, in human hepatocellular carcinomas

Deletions of the Tg737 gene, whose product is involved in liver oval cell proliferation, differentiation, and ploidy control, have been recently shown in chemically induced rat liver tumors and in a limited series of patients with hepatocellular carcinoma (HCC). Thus, Tg737 has been proposed as a candidate new liver-specific tumor suppressor gene. To investigate this important issue, we analyzed the structure and expression pattern of the Tg737 gene in a group of 23 tumorous and adjacent nontumorous liver tissues, by combining polymerase chain reaction (PCR) and Southern and Northern blot-based analyses. We failed to identify deletions or gross alterations of the Tg737 gene by both PCR and Southern blot analyses. Northern blots showed comparable accumulation of normal Tg737 transcripts in both tumorous and nontumorous tissues. Collectively, therefore, our results do not support the hypothesis of frequent Tg737 genetic alterations in human HCC.

Viral and host factors in determining response of relapsers with chronic hepatitis C to retreatment with interferon

In chronic hepatitis C the rate of relapse after an end-of-treatment response to interferon may exceed 50%. The usefulness of retreatment of relapsers with interferon in obtaining a complete sustained response and the role of clinical, virological and immunological features in determining long-term efficacy of retreatment are unclear. We aimed to assess the efficacy of interferon retreatment in obtaining a complete sustained response, to evaluate whether increasing the dose may enhance responsiveness, and to identify possible predictors of sustained response. We enrolled 42 patients with biopsy-proven chronic hepatitis C without cirrhosis who had previously responded to a six-month course of Interferon-alpha2b (total dose: group A, 22 patients, 234 MU; group B, 20 patients, 468 MU) and then relapsed. All, except one, were HCV-RNA negative at the end of first cycle of interferon; most (31/42, 74%) were infected by HCV 1b. Subjects were randomly allocated to receive another cycle of interferon either at the original dose (group A1: 234 MU, 11 patients; group B1 468 MU, 10 patient) or twice the original dose (group A2: 468 MU, 11 patients; group B2: 936 MU, 10 patients). At the end of the second cycle of interferon, 24 subjects (57%) had normal ALT and were HCV-RNA negative, and 16 (39%) had normal ALT, but were HCV-RNA positive. A complete sustained response was obtained in eight patients (19%), at a similar rate in all treatment groups. Complete sustained responders were different from the other patients in terms of age (35.9 +/- 10.4 vs 44.1 +/- 8.8, P = 0.027), rate of infection with non-1b HCV (6/8 vs 5/34, P = 0.0005), serum HCV-RNA (74,016 vs 321,428 median copies/ml, P = 0.037) and serum levels of 90K/MAC-2 BP (5.76 +/- 3.01 vs 10.25 +/- 5.16 units/ml, P = 0.02), an N-glycoprotein implicated in cellular defense functions. Multivariate logistic analysis validated age and HCV genotype as independent predictors of CSR. Among noncirrhotic relapsers who received a total interferon dose > or = 234 MU in the first cycle, retreatment usually induced end-of-treatment response. A complete sustained response was obtained in only one of every five subjects. Increasing the dose of interferon above that of the first cycle did not enhance the rate of sustained response. In conclusion we might assert that young subjects infected by non-1b HCV and with low levels of HCV-RNA and of 90K/MAC-2 BP are the best candidates for retreatment.

Regulation of the sea urchin early H2A histone gene expression depends on the modulator element and on sequences located near the 3' end

Transcription of the sea urchin early histone genes occurs transiently during early cleavage, reaching the maximum at the morula stage and declining to an undetectable level at the gastrula stage. To identify the regulatory elements responsible for the timing and the levels of transcription of the H2A gene, we used promoter binding studies in nuclear extracts and microinjection of a CAT transgene driven by the early H2A promoter. We found that morula and gastrula nuclear proteins produced indistinguishable DNase I footprint patterns on the H2A promoter. Two sites of interactions, centred on the modulator/enhancer and on the CCAAT box respectively, were detected. Deletion of the modulator or coinjection of an excess of modulator sequences severely affected the expression of two transgenes driven by the enhancer-less and modulator-containing H2A promoter. Finally, a DNA fragment containing 3' coding and post-H2A spacer sequences, where upon silencing three micrococcal nuclease hypersensitive sites were previously mapped, specifically repressed at the gastrula stage the expression of the transgene driven by the H2A promoter. These results indicate that the modulator is essential for the expression of early H2A gene and that sequences for downregulation are localized near the 3' end of the H2A gene.

Long-term course of interferon-treated chronic hepatitis C

BACKGROUND/AIMS

To evaluate whether sustained response to a-interferon improves clinical outcome in patients with chronic hepatitis C.

METHODS

A cohort of 410 consecutive patients (65% with chronic hepatitis, 35% with cirrhosis) were treated with a-interferon in two trials (mean follow-up 62.1 months, range 7-109 months). All were serum HCV RNA positive before therapy and received first 10 then 5 million units of a-2b or a-nl interferon three times weekly for 6 to 12 months. Sustained response was defined as normal aminotransferases 12 months after stopping interferon.

RESULTS

Sixty-two patients (15.1%: 54 with chronic hepatitis, eight with cirrhosis) were sustained responders. At the end of follow-up, 56 out of 62 sustained responders (90.3%) were serum HCV RNA negative. No biochemical relapse after 12 months was seen in sustained responders, regardless of initial histology, HCV genotype or persistence of HCV RNA. Although three died of non-hepatic causes, no liver-related events were observed among sustained responders. Complications of liver disease occurred in 34 relapsers/non-responders: nine hepatocellular carcinomas, 21 ascites and four portal hypertensive bleedings. Eleven relapsers/nonresponders died: eight of hepatic and three of non-hepatic causes. Event-free survival was significantly longer in sustained responders than in all the remaining patients. In a regression analysis, sustained response to interferon, low age and absence of cirrhosis were independent predictors of event-free survival.

CONCLUSIONS

Hepatitis C virus is probably eradicated and progression of liver disease is prevented in most patients who remain HCV RNA negative with normal transaminases for more than 1 year after stopping treatment.

HCV viraemia is more important than genotype as a predictor of response to interferon in Sicily (southern Italy)

BACKGROUND/AIMS

To investigate host- and virus-related factors predictive of early and sustained alanine aminotransferase normalization after interferon therapy for HCV-related chronic liver disease, in an area where genotype 1 is highly prevalent.

METHODS

We studied 100 patients with HCV-RNA positive chronic liver disease (73 chronic hepatitis and 27 cirrhosis) undergoing alpha-interferon treatment. Thirty-four patients had an early response but relapsed, 15 patients remained into sustained response for at least 12 months after therapy, and 51 patients did not respond. Serum HCV-RNA levels were assessed by bDNA (Chiron), and genotype by LiPA (Innogenetics) and by sequencing of the 5' non-coding region.

RESULTS

Mean pre-treatment HCV-RNA level (x 10(3) genome equivalents/ml +/- SD) was lower in sustained responders (3854 +/- 7142) than in relapsers (9587 +/- 10163) or in non-responders (5709 +/- 6618). HCV subtype 1b was highly prevalent (82%), while types 1a, 2a, 3 and 4 were rare (about 5% each). However, the prevalence of 1b was much lower (31%) under 40 years of age. The prevalence of subtype 1b among sustained responders (74%) was similar to that observed among relapsers (82%) or non-responders (84%), but some nucleotide substitutions in the putative RNA loop of the 5' non-coding region were seen only among relapsers or non-responders. Multiple logistic regression model showed that early response to interferon was predicted by absence of cirrhosis and a pre-treatment HCV-RNA level below 350. Sustained response to interferon was predicted by pre-treatment HCV-RNA level below 350 and a low fibrosis score.

CONCLUSIONS

Among patients with hepatitis C from an area where subtype 1b is highly prevalent, absence of cirrhosis and low pre-treatment serum HCV-RNA level are the most important predictors of response to IFN. Some nucleotide substitutions found in the 5' non-coding region of subtype 1b are associated with non-response or relapse.

Modulator factor-binding sequence of the sea urchin early histone H2A promoter acts as an enhancer element

The sea urchin early H2A histone gene, like the other four members of the repeating units, is transiently expressed during very early development. To investigate the mechanisms underlying the faithful expression of the early H2A gene, we focused our attention on the modulator element. We showed by DNase I cleavage protection patterns that the modulator includes the upstream sequence element 1 (USE1) and mapped at nucleotides -137 to -108 in the early H2A gene promoter. Functional tests conducted by microinjection into sea urchin embryos then showed that the modulator element binds the transcriptional factor called modulator-binding factor 1 (MBF-1). We found in fact that coinjection of an excess of the MBF-1-binding site, either as the modulator or as the USE1, efficiently impaired the activity of the H2A promoter. An unexpected finding was the expression of the reporter gene from the early H2A promoter at the gastrula stage of embryonic development, when the early histone genes are transcriptionally silent. In addition, we also found that the modulator element was active at the gastrula stage. The potential enhancer activity of the modulator was tested by microinjecting several constructs containing single or multiple copies of the modulator element placed 5' or 3' to a thymidine kinase gene (tk) promoter in both sea urchin embryos and Xenopus laevis oocytes and determining the expression of a reporter chloramphenicol acetyltransferase gene under the control of the linked tk promoter. We found that an oligonucleotide bearing the MBF-1-binding site activates the expression of the reporter gene independently of the position and orientation. We conclude that the modulator binds the MBF-1 activator and that it is a transcriptional enhancer of the early H2A histone gene.

Sea urchin early histone H2A modulator binding factor 1 is a positive transcription factor also for the early histone H3 gene

To shed some light on the mechanisms involved in the coordinate regulation of the early histone gene set during sea urchin development, we tested the hypothesis that the upstream sequence element USE1, previously identified in the early H2A modulator, could also participate in the transcription of the early histone H3 gene. We found by DNAse I protection analysis and by competition in electrophoretic mobility-shift experiments that two sequence elements of the H3 promoter closely resembled the USE1-H2A sequence in their binding activity for nuclear factors from 64-cell stage embryos. These modulator binding factor 1 (MBF-1)-related factors seem to recognize the ACAGA motif that is conserved between the USE1-like sequences of both H2A and H3 promoters. In fact, excess oligonucleotide containing a mutated USE1-H2A element in which the ACAGA sequence was mutated to AGTCA failed to compete with the USE1 sites of both H2A and H3 genes for interaction with MBF-1. Finally, in vivo transcriptional analysis in both Xenopus and sea urchin showed that an excess of USE1-H2A element efficiently competed for the activity of the H3 promoter. From these results we conclude that MBF-1 is a transcription factor conserved between sea urchin and frog and that MBF-1 or related transcription factors are involved in the coordinate expression of both H2A and H3 early histone genes.

Cis-acting elements of the sea urchin histone H2A modulator bind transcriptional factors

Functional tests, performed by microinjection into Xenopus laevis oocytes, show that a DNA fragment containing the modulator of the early histone H2A gene of Paracentrotus lividus enhances transcription of a reporter gene when located, in the physiological orientation, upstream of the tk basal promoter. Gel retardation and DNase I footprinting assays further reveal that the H2A modulator contains at least two binding sites [upstream sequence elements 1 and 2 (USE 1 and USE 2)] for nuclear factors extracted from sea urchin embryos, which actively transcribe the early histone gene set. Interestingly, USE 1 is highly homologous to a cis-acting element previously identified in the H2A modulator of Psammechinus miliaris [Grosschedl, R., Mächler, M., Rohrer, U. & Birnstiel, M. L. (1983) Nucleic Acids Res. 11, 8123-8136]. Finally, a cloned oligonucleotide containing the USE 1 sequence competes efficiently in Xenopus oocytes with the H2A modulator to prevent enhancement of transcription of the reporter gene. From these results, we conclude that USE 1 and perhaps USE 2 in the H2A modulator are upstream transcriptional elements that are recognized by trans-acting factors common to Xenopus and sea urchin.