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G V Gregorio

Publications and source records attributed to G V Gregorio.

At least 19 recordsLinked to original sources
PubMed2003

Mimicry between the hepatitis C virus polyprotein and antigenic targets of nuclear and smooth muscle antibodies in chronic hepatitis C virus infection.

Autoantibodies to smooth muscle (SMA) and nuclear components (ANA) arise in the natural course of chronic infection with hepatitis C virus. In view of the growing evidence for 'molecular mimicry' as a mechanism of autoimmunity we investigated whether cross-reactive immune reactions between host smooth muscle/nuclear components and HCV antigens may contribute to the formation of SMA and ANA in chronic HCV infection. Computer-assisted protein database search methods were used to identify three smooth muscle (smoothelin698-717, myosin1035-1054, vimentin69-88) and three nuclear (matrin722-741, histone H2A11-30, replication protein A133-152) host antigens with the highest local sequence similarity to the HCV polyprotein and 20-mer peptides corresponding to these regions were constructed. Sera from 51 children with chronic HCV infection [median age: 8 (2-16); 27 boys], 26 SMA positive and five ANA positive, were tested for reactivity to the synthesized HCV peptides and their human homologues by enzyme linked immunosorbent assay (ELISA). Sera from patients with HBV infection and chronic liver disease of different aetiologies were used as controls. 'Double reactivity' to HCV peptides and smooth muscle/nuclear homologues was associated strongly with HCV infection (P < 0.001 for both). Humoral cross-reactivity was established as the basis for double recognition by competition ELISA. Double-reactivity to smooth muscle and HCV peptide antigens correlated with SMA positivity by indirect immunofluouresence (P = 0.05). Of 15 patients double-reactive to myosin1035-1054 and its HCV homologue, 13 recognized whole myosin by immunoblot. These results suggest that ANA and SMA in chronic HCV infection may arise, at least in part, as a consequence of cross-reactive immune responses to HCV and host smooth muscle/nuclear antigens.

Adolescent↗
PubMed2001

Autoimmune hepatitis/sclerosing cholangitis overlap syndrome in childhood: a 16-year prospective study.

To investigate whether sclerosing cholangitis with an autoimmune serology characteristic of autoimmune hepatitis (AIH) and AIH are distinct entities, we studied 55 consecutive children with clinical and/or biochemical evidence of liver disease and circulating antinuclear (ANA), anti-smooth muscle (SMA), and/or liver-kidney-microsomal type 1 (LKM1) autoantibodies. They underwent liver biopsy, direct cholangiography, sigmoidoscopy, and rectal biopsy at presentation. Twenty-eight were diagnosed as AIH in the absence and 27 autoimmune sclerosing cholangitis (ASC) in the presence of radiological features of cholangiopathy. Twenty-six ASC and 20 AIH had ANA and/or SMA; 1 ASC and 8 AIH LKM1 autoantibody. Similarities between the 2 conditions included most clinical and biochemical parameters and a lower frequency of HLA DR4. Inflammatory bowel disease and histological biliary changes were more common in ASC; coagulopathy, hypoalbuminemia, lymphocytic periportal hepatitis, and HLA DR3 were more common in AIH. Histological biliary changes were observed in 65% of ASC and 31% of AIH patients. Eighty-nine percent responded to immunosuppression. Follow-up liver biopsies from 17 ASC and 18 AIH patients had similarly reduced inflammatory activity and no progression to cirrhosis. Sixteen follow-up cholangiograms from AIH patients and 9 from ASC patients were unchanged, while 8 ASC patients showed a progressive cholangiopathy. One child with AIH and ulcerative colitis developed sclerosing cholangitis 8 years after presentation. At 2 to 16 years (median, 7 years) from presentation, all patients are alive, including 4 ASC patients who underwent liver transplantation. In conclusion, ASC and AIH are similarly prevalent in childhood; cholangiography is often needed to distinguish between these 2 entities, which are likely to lie within the same disease process.

Adolescent↗
PubMed2000

Long term effect of alpha interferon in children with chronic hepatitis B.

BACKGROUND/AIMS: The purpose of this study was to better define the long term prognosis of infection and disease in children with chronic hepatitis B treated with interferon (IFN) alpha. PATIENTS: A total of 107 children with chronic hepatitis B who received IFN alpha for three or six months in two clinical trials were followed for a mean period of 69 (17) months. Response to treatment was defined as loss of hepatitis B e antigen (HBeAg) within 12 months after stopping treatment. A control group of 59 patients was also followed for a shorter mean time (46 (19) months). RESULTS: Sixteen (15%) treated children responded during therapy and 18 (17%) during post-treatment follow up; 31 (29%) non-responders lost HBeAg during subsequent years. High pretreatment levels of transaminases and a greater histological activity index were predictors of response. Kaplan-Meier estimates of cumulative HBeAg clearance rates at five years were similar between treated patients (60%) and controls (65%). After HBeAg clearance, all cases lost hepatitis B virus DNA and 94% had normal transaminase levels. Loss of hepatitis B surface antigen (HBsAg) occurred in four (25%) patients who responded during treatment but in none of the other treated or untreated patients. CONCLUSIONS: After five years' observation, the proportion of treated children with sustained HBeAg clearance comprised an equal number of responders and non-responders and did not differ from that observed in untreated controls, suggesting that IFN simply accelerated a spontaneous event. However, IFN significantly improved the rate of HBsAg loss in cases with more prominent disease activity who were early responders, and may be particularly useful in this type of patient.

Adolescent↗
PubMed1999

Mimicry between the hepatitis B virus DNA polymerase and the antigenic targets of nuclear and smooth muscle antibodies in chronic hepatitis B virus infection.

Autoantibodies to nuclear and smooth muscle are common in hepatitis B virus (HBV) infection. To understand their origin, we scanned protein databases and found that HBV-DNA polymerase (HBV-pol) shares 7-9 amino acid sequences with nuclear (MHC II trans-activator, nuclear pore core protein, nuclear mitotic apparatus, and polymyositis sclerosis Ag) and smooth muscle proteins (caldesmon and myosin). Twenty-mer peptides with relevant homologues and an irrelevant control peptide were constructed and ELISAs were established. Sixty-five children with chronic HBV infection, 104 patients with other chronic liver diseases (CLD), 36 patients with extrahepatic autoimmune diseases, and 24 healthy controls were investigated. Double reactivity to HBV-pol peptides and corresponding self homologues was observed in 40% of HBV-positive patients as compared with four (4%) with other chronic liver diseases, two (6%) with extrahepatic autoimmune diseases, and in none of the healthy controls (p < 0.001 for all). Double reactivity to myosin or caldesmon peptides and their HBV-pol homologues was associated with anti-smooth muscle Ab positivity by immunofluorescence (p < 0.05 for both). HBV-positive sera double reactive for myosin or caldesmon and their homologous HBV-pol peptides also reacted with the native proteins on immunoblot. Fifty to ninety percent Ab inhibition to individual HBV-pol and HBV-pol99-118 peptides was noted by preincubation with individual HBV-pol/self homologue peptide and native proteins, respectively, but not with control peptide. Our results show that cross-reactive immunity targeting homologous sequences of viral and self proteins may partly account for autoantibody production in HBV infection.

Adolescent↗
PubMed1999

The role of HBV DNA quantitative PCR in monitoring the response to interferon treatment in chronic hepatitis B virus infection.

BACKGROUND/AIMS: To investigate whether the measurement of HBV DNA by quantitative polymerase chain reaction (PCR) is helpful in monitoring response to interferon treatment in chronic hepatitis B virus infection, we have determined sequentially serum levels of HBV DNA during and up to 18 months after treatment, in 10 patients with a sustained response (all anti-HBe positive, five also HBsAg negative and anti-HBs positive) and, as controls, in 12 non-responders. METHODS: Serum HBV DNA was measured by standard hybrisation assay (Genostics, Abbott) and by quantitative PCR (Amplicor HBV Monitor test, Roche Diagnostic Systems). RESULTS: A clear difference in HBV viral load between responders and non-responders was observed from the fourth week of treatment and was maintained throughout the study period. At the last follow up 16-26 (median 21) months after starting treatment, all the 10 responders were HBV DNA negative by hybridisation. By PCR, however, five (one anti-HBs and four anti-HBe positive) were still HBV DNA positive. In addition, one anti-HBs positive patient HBV DNA negative by PCR at last follow up, had fluctuating levels of HBV DNA by PCR during the observation period, only intermittently falling below the threshold of the assay. CONCLUSIONS: The measurement of HBV DNA by quantitative PCR provides early prediction of response to interferon, allowing prompt modification of treatment. With this technique, HBV DNA is detected in a high proportion of sustained responders, suggesting that HBV may never be completely eliminated by interferon treatment, even after anti-HBs seroconversion.

Adolescent↗
PubMed1998

Immunological cross-reactivity to multiple autoantigens in patients with liver kidney microsomal type 1 autoimmune hepatitis.

We describe two patients with liver kidney microsomal antibody type 1 (LKM1)-positive autoimmune hepatitis (AIH) with associated endocrinopathies. The first patient had insulin-dependent diabetes (IDDM), and the second patient had Addison's disease and hypoparathyroidism, and is also positive for islet cell antibodies, without overt diabetes. To account for the existence of multiple endocrinopathy in these patients, we investigated whether there is sequence similarity between the target of LKM1 antibodies, cytochrome P4502D6 (CYP2D6), and other human proteins, and if so, whether this structural similarity produces a detectable cross-reactive immune response. Our database search identified two proteins, carboxypeptidase H, an autoantigen in insulin-dependent diabetes, and 21-hydroxylase, the major autoantigen in Addison's disease, that share sequence similarity to the second major LKM1 epitope on CYP2D6. We tested the reactivity of sera from these patients to the homologous regions of the three autoantigens using an enzyme-linked immunosorbent assay (ELISA). The cut-off for positivity was established by testing sera from 22 healthy children. To determine the significance of reactivity to the peptide homologues of the three autoantigens, we investigated 16 additional patients with LKM1 AIH and 20 children with chronic hepatitis B virus infection as pathological controls. We found that reactivity to the second major epitope of CYP2D6 is significantly associated with reactivity to the homologous regions of carboxypeptidase H (CPH) and 21-hydroxylase (21-OHase) in patients with LKM1 AIH, and that this simultaneous recognition is cross-reactive. We suggest that a cross-reactive immune response between homologous autoantigens may contribute to the development of multiple endocrinopathies in LKM1 AIH.

Amino Acid Sequence↗
PubMed1998

Autoantibody prevalence in children with liver disease due to chronic hepatitis C virus (HCV) infection.

HCV infection and interferon-alpha (IFN-alpha) therapy have been associated with autoimmunity. To assess whether chronic liver disease (CLD) due to HCV infection or its treatment with IFN-alpha cause autoimmune manifestations, the prevalence of tissue autoantibodies in 51 children with chronic HCV infection and 84 with other CLD was analysed by standard techniques. Sixty-five percent of patients with chronic HCV infection, 66% with chronic hepatitis B infection and 60% with Wilson's disease were positive for at least one autoantibody. In the 51 subjects with chronic HCV infection (29 treated with IFN-alpha, 22 untreated), tested on 165 occasions over a median of 9 months (range 5-42 months), autoantibodies to nuclei (ANA), smooth muscle (SMA), gastric parietal cell (GPC) and/or liver kidney microsomal type 1 (LKM-1) were similarly prevalent in treated and untreated patients (90% versus 68%, P = 0.12). Positivity for SMA was present in 67%, GPC in 32%, ANA in 10%, LKM-1 in 8% of cases. Treatment with IFN-alpha had to be suspended due to transaminase elevation in one SMA-positive, one ANA-positive but in three of four LKM-1-positive patients. Our results show that: (i) autoantibodies are common in viral-induced hepatitis and Wilson's disease; (ii) positivity for SMA, GPC, ANA is part of the natural course of chronic HCV infection, their prevalence being unaffected by IFN-alpha; and (iii) IFN-alpha should be used cautiously in the treatment of LKM-1/HCV-positive patients.

Adolescent↗
PubMed1997

Autoimmune hepatitis in childhood: a 20-year experience.

To determine the clinical, biochemical, and histological features, and outcome of childhood autoimmune hepatitis (AIH), we reviewed the medical records of 52 children with AIH, 32 (median age: 10 [2-15] years) anti-nuclear and/or smooth muscle antibody (ANA/SMA) positive, 20 (7 [0.8-14] years) liver/kidney microsomal antibody (LKM-1) positive, with median follow-up of 5 years (range 0.3-19). At presentation: 56% had symptoms of prolonged acute hepatitis; LKM-1 positive were younger (P = .011), with higher bilirubin (P = .007), and AST (P = .047); ANA/SMA positive had lower albumin (P = .023); 69% ANA/SMA positive, and 38% LKM-1 positive were cirrhotic (P = .080). ANA/SMA positive had increased frequency of HLA haplotype A1/B8/DR3/DR52a compared with controls (53% vs. 14%, P < .001). Of six (5 LKM-1 positive) with fulminant hepatitis, four were transplanted, one died, and one ANA/SMA positive improved with immunosuppression. Of 47 treated with immunosuppression, 2 (1 LKM-1 positive) died with no remission and 4 (2 LKM-1 positive) were transplanted 8 to 14 years after diagnosis. Immunosuppression was stopped successfully in 19% of ANA/SMA positive after a median of 3 years of treatment, but in none of LKM-1 positive. Baseline bilirubin and international normalized prothrombin ratio (INR) were independent variables predictive of outcome. In conclusion, ANA/SMA positive and LKM-1 positive AIH in childhood have clinical, biochemical, and histological differences, but similar severity and long-term outcome.

Adolescent↗
PubMed1997

A 12-year-old girl with antimitochondrial antibody-positive autoimmune hepatitis.

Autoimmune hepatitis is rare and, in childhood, is typically associated with either the nuclear and/or smooth muscle antibody or with the liver kidney microsomal type 1 antibody. Antimitochondrial antibodies, which are considered diagnostic of primary biliary cirrhosis, have not been described in the paediatric age. We report for the first time a 12-year-old girl with antimitochondrial-antibody-positive autoimmune hepatitis. Antimitochondrial antibody positivity was determined by immunofluorescence and immunoblot. The patient's age, clinical, biochemical and histological features and response to immunosuppressive treatment support the diagnosis of autoimmune hepatitis.

Aspartate Aminotransferases↗
PubMed1996

Lymphoblastoid interferon alfa with or without steroid pretreatment in children with chronic hepatitis B: a multicenter controlled trial.

The comparative efficacy of prednisolone followed by interferon alfa (IFN-alpha) versus IFN-alpha alone in enhancing the rate of antibody to hepatitis B e antigen (anti-HBe) seroconversion has not been evaluated in a large cohort of white children. To determine this, a multicenter-controlled trial was conducted in 95 hepatitis B virus (HBV)-DNA/hepatitis B e antigen (HBeAg)-positive children (median age, 9 years [range, 2-16 years]; 56 boys; 84 [89 percent] white), all having inflammatory changes on liver biopsy. Patients were randomized to receive either prednisolone followed by IFN-alpha (n = 34); placebo followed by IFN-alpha (n = 30); or no treatment (n = 31). The prednisolone/placebo was given on a double-blind basis. Lymphoblastoid IFN-alpha was given at 5 MU/m(2) three times a week for 12 weeks. Baseline clinical, biochemical, and histological features were similar for the three groups. The majority (85 percent) had a baseline aspartate aminotransferase (AST) level < or = 100 IU/L. On follow-up between 12 and 18 months (median, 15 months) after treatment, the loss of HBeAg with anti-HBe seroconversion was more common in patients pretreated with steroids (12 of 34 [35 percent]) or placebo [12 of 30 (40 percent)] as against controls (4 of 31 [13 percent], P< .05). Factors predictive of anti-HBe seroconversion were baseline HBV-DNA concentration of < or = 1,000 pg/mL and a greater degree of portal tract inflammation on pretrial biopsy. Our results show that in white children treatment with IFN-alpha, at the dose and duration used in this study, improves the rate of anti-HBe seroconversion. Steroid priming does not potentiate the effect of IFN-alpha.

Adolescent↗
PubMed1996

Autoantibody prevalence in chronic hepatitis B virus infection: effect in interferon alfa.

The most effective treatment of chronic hepatitis B virus (HBV) infection is interferon alfa (IFN-alpha), a potentially severe side effect of which is the induction of autoimmunity. To assess whether IFN-alpha causes clinical or serological autoimmune manifestations, we studied 61 children randomized to receive 5 MU/m2 of IFN-alpha three times per week for 12 weeks, with or without steroid priming or no treatment. Autoantibodies to antinuclei (ANA), smooth muscle (SMA), gastric parietal cell (GPC), liver kidney microsomal type 1, mitochondrial, liver cytosolic antigen, thyroid microsomal, and thyroid globulin were detected by standard techniques. Over a median of 4 years (range, 1-5 years) from randomization, no clinical signs of autoimmunity were observed. Autoantibody positivity for nuclei, smooth muscle, and/or gastric parietal cells was observed on at least one occasion in 42 of 61 children (69%), with no overall difference in the prevalence between patients treated with interferon alone (19 of 24 [79%]), steroids plus interferon (13 of 20 [65%]), or untreated controls (10 of 17 [59%]). There was also no difference in the autoantibody prevalence before, during, and at follow-up after cessation of treatment in both interferon-treated and interferon-untreated patients. Autoantibodies are common in chronic HBV infection, and their prevalence is uninfluenced by IFN-alpha.

Adolescent↗
PubMed1995

Significance of extractable nuclear antigens in childhood autoimmune liver disease.

Antinuclear antibody (ANA) is found in connective tissue disorders and in autoimmune liver disease. While ANA-positive connective tissue disorders are subdivided according to possession of specific antibodies to extractable nuclear antigens (ENA) (anti-ribonucleoprotein (anti-RNP), anti-Smith (anti-Sm), anti-Ro, anti-La), little is known about the presence and significance of ENA in autoimmune liver disease. To investigate this, we have tested 35 children with autoimmune hepatitis (AIH) (19 ANA and/or smooth muscle antibody-positive (ANA/SMA+ve); 16 liver kidney microsomal 1-positive (LKM-1 + ve)) and 14 with ANA/SMA+ve autoimmune sclerosing cholangitis (ASC), using both double dimension immunodiffusion and ELISAs. Eighty children with non-autoimmune liver disease (20 alpha 1-antitrypsin deficiency, 20 Wilson's disease, 20 Alagille's syndrome and 20 chronic hepatitis B virus infection) and 20 healthy controls were also tested. ENA were detected in seven (20%) patients with AIH: two ANA-positive, one SMA-positive and four LKM-1-positive. Three were positive for anti-Sm, two for anti-La, one for anti-Sm/anti-La and one for anti-Sm/anti-La/anti-Ro. ENA-positive had more severe liver disease than ENA-negative patients (P < 0.03). ENA were not detected in ASC, non-autoimmune liver diseases and controls. Our results indicate that ENA reactivity, including anti-Sm and anti-La, characteristic of systemic lupus erythematosus and Sjögren's syndrome, respectively, are present in some patients with AIH even in the absence of ANA, and may characterize a particularly severe form of the disease.

Adolescent↗
PubMed1995

Anti-liver cytosolic antigen type 1 (LC1) antibodies in childhood autoimmune liver disease.

Antibodies to liver cytosol antigen type 1 (anti-LC1), which recognize a 60-kd peptide contained in the liver cytosolic fraction, have been reported to define a subset of autoimmune hepatitis (AIH) either negative for other autoantibodies or positive for anti-liver kidney microsomal antibody type 1 (LKM-1) and to be best detected in immunodiffusion. To analyze the prevalence of anti-LC1 in childhood liver disease, we have tested the sera of 95 patients using immunoblot, indirect immunofluorescence, and immunodiffusion. Fifteen children had smooth muscle antibody (SMA) and/or anti-nuclear antibody (ANA)-positive AIH, 13 had anti-LKM-1-positive AIH, 14 had autoimmune sclerosing cholangitis (ASC) (all SMA and/or ANA positive), and 53 had non-autoimmune liver disease (10 had alpha 1-anti-trypsin deficiency [alpha 1-ATD], 11 had Wilson's disease [WD], 14 had Alagille's syndrome, and 18 had chronic hepatitis B virus [HBV] infection). Twenty healthy children were studied as controls. Anti-LC1 positivity in immunodiffusion and strong reactivity in immunoblot were found in 4 LKM-1- and 2 SMA/ANA-positive patients with AIH and in 1 patient with ASC, but in none of the patients with other liver diseases nor in controls. A weak 60-kd band was detected by immunoblot in 6 more patients with AIH (2 were LKM-1- and 4 were SMA/ANA-positive) and 6 patients with ASC, all anti-LC1-negative by immunofluorescence and immunodiffusion. No distinct clinical features characterized the anti-LC1-positive patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1994

Viral hepatitis in children with renal disease.

Specific and sensitive diagnostic tests are now available to identify type A, B, C, D and E hepatitis. Hepatitis A and E which cause only acute, very rarely fulminant, hepatitis are spread largely by the faecal-oral route, having a brief viraemic phase. Hepatitis B, C and D which are transmitted parenterally and via secretions are often associated with chronic viraemia. Patients with chronic renal disease are at particular risk. Impaired immunity due to disease or drugs increases the propensity to develop a chronic carrier state which may progress to cirrhosis and hepatocellular carcinoma. Limited reports indicate that hepatitis C infection may cause cirrhosis more rapidly than hepatitis B. The emergence of mutants to both hepatitis B and C is a cause for concern. Treatment with interferon is of limited efficacy. Screening of blood products for viral markers and prudent handling of potentially infected materials to avoid contamination of damaged skin or mucous membrane are the best strategies to prevent infection. Hepatitis B vaccination of all newborns, young adolescents and those at risk is the most effective means of reducing the carrier frequency.

Child↗
PubMed1994

Viral hepatitis.

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Adolescent↗