Al118 AASLD ABSTRACTS GASTROENTEROLOGY, Vol. 108, No. 4

• IMMUNOREACTIV1TY OF HEPATITIS C VIRUS CORE ANTIGEN IN CHRONIC HEPATITIS C Marousis CG, Quan S 1, Davis GL, Polito A 1, DiNello R 1, Mizokami M 2, Lau JYN. University of Florida, Gainesvllle, FL; Chiton Corporation 1, Emeryville, CA; and Nagoya City University 2, Nagoya, Japan.

Background: HCV core antigen has been shown to be immunogenic at the B-cell level. Recently, Machida et al reported that peptides derived from the HCV core region can be used for the capture of HCV genotype-specific antibodies. Aim: To characterize the immunoreactivity of HCV core antigen in chronic HCV infection. Methods: (1) The hydrophobicity and antigenieity profde of the HCV core peptide were determined using the methods of I-Iopp and Woods, and Welllngs et al respectively. (2) 27 chronic HCV patients (M:F 17:10, age 30-71 years, HCV RNA+ in all by RT-PCR CoDNA + 18/27), histology: CPH/CAH/c~v~osis 6/9/12] ~,~re studied. Seroreactivity to various HCV antigens in the RIBA-2 and RIBA-3 . . . . (Chiton) assay was determined. (3) The reactivity to the recombinant core antigen (derived from HCV1, genotype la), HCV core peptides 10-53 and 72-89 were assessed using the RIBA strip technology. (4) The immunorcaetivity to the core peptides sub-1 and sub-2 (amino acid residues 65-81) was evaluated. HCV genotype was determined by both an NS4-peptide based serological assay (type 1 n= lT , type 2 n=5, type 3 n=2, non-reactive n=3) and a reverse hybridization assay based on H C V 5 'NC region (LiPA, Innogenet ies , Belgium)[genotype la n=l l , lb n=7, 1 (a/b not defined) n=l , 2a n=2, 2b n=3, 2 (a/b not defined) n = 1, 3a n = 2]. Results: ( ! ) Hydrophobicity and antigenieity profiles predict that amino acids residues 12-100 were likely to harbor B-cell epitopes. (2) 25/27 patients had B-eell immunorcactivity to HCV core antigen (c-22) compared with 16 to 5-1-1, 22 to c-100, 25 to c33c, 23 to el00 peptides, 19 to NS5 antigens. The two patients negative for immunoreactivity to HCV core had no reactivity to all the other antigens tested (genotype la n = 1, lb n = 1). (3) 25/27 patients reactive to the HCV core antigen were also reactive to the HCV core peptide 10-55 (all showing 4+ reactivity) but only 14/27 showed reactivity to peptide 72-89 (2+, u=5, 3+ n=2, 4+ n=7). There were no clinical (age, sex, mode of transmission, duration of infection), biochemical (liver profde), or virological characteristics (HCV viremia, HCV genotype) associated with the reactivity to the HCV core peptide 72-89. (4) Only 13/27 had antibody react against sub-1 and sub-2 peptides (sub-1 n= 10, sub-2 u=2, both sub-1 and sub-2 u= 1). 11/13 had their type-specific seroreaetivity correspond to their genotype, one was reactive to sub-1 but was found to have HCV genotype 2b, the patient who was reactive to both sub-1 and sub-2 had HCV genotype 3a. Conclusions: (1) HCV core antigen is highly immanogenie in humans at the B-cell level. (2) The B-cell epitope within core amino acid residues 10-55 is more immunogenie than 72-89. (3) Defining HCV genotypes based on the core peptides as described by Machida et al had only a fair sensitivity in US patients with chronic HCV infection.

• PROSPECTIVE CONTROLLED TRIAL OF INTERFERON-ALPHA. F O R CHRONIC HEPATITIS B IN ASIAN-AMERICANS. P. Martin, HL Hann', S. Westerberg', $1Munoz*, WC Maddrey ÷. UCLA School of Medicine, Los Angeles, CA, *Jefferson Medical College, Philadelphia PA, +University of Texas Southwestern, Dallas, TX.

On a worldwide basis the major disease burden of chronic hepatitis B (HBV) infection exists in areas of high endemicity including Asia, Sub-Saharan Africa and Alaska. Emigration by individuals from these areas has resulted in communities within the United States with hig h rates of HBV infection. Although interferon-alpha has documented efficacy in the treatment of chronic hepatitis B, little information exists about its use in non-Caucasian patients with presumed life-long HBV infection. Aim: To evaluate the efficacy of interferon-alpha therapy in Asian-Americans with chronic HBV infection compared to a control group of Cancasians. Methods: Adult patients, Asians and Caucasians, > 18 years of age with chronic HBV infection documented for at least 6 months, HBeAg present in serum and with compensated liver disease were eligible. Patients had entry liver biopsies. Patients with ALT levels < 3 times the upper limit of normal received prednisone "priming" starting at 60mg for 2 weeks tapered in 20rag increments every 2 weeks with a 2 week break before starting interferon. All patients received interferon alpha 2b 5 million units daily sc for 16 weeks. Follow-up with serial HBV serologies and liver chemistries was continued for 1 year following completion of therapy. Results: Asians (n=13) Caucasians (n=10) Age (years) 39_+8 43_+13 NS Cirrhosis 5(38%) 2(20%) NS HBV DNA(pg/ml) 82.8_+ 171.8 168.9+ 132.8 NS ALT (Iu/L) 199_+ 129 249_+235 NS Predulsone 1(8%) 4(40%) p< .05 Loss of e antigen 8(62%) 6(60%) NS In addition, four of the Caucasian responders but none of the Asian responders lost HBsAg. Therapy was generally well tolerated although 2 Caucasian patients had exacerbation of pre-existing depression, 1 additional Caucasian patient needed dose reduction because of fatigue and 1 Asian patient withdrew from the study because of thrombocytopenia. Loss of HBeAg was associated with a fall in aminotransferase levels. Conclusions: Interferon-alpha therapy for chronic HBV infection results in loss of HBeAg in adult Asian-American patients at a rate comparable to Caucasian patients. Larger term follow-up is needed to assess whether loss Of HBeAg as a result of interferon therapy is durable in Asian patients and alters the long-term consequences of HBV infection. Presumed neonatal or infancy acquired HBV infection is not a predictor of non-response to anti-viral therapy. This research was funded in part by Schering-Plough Corporation, Kenilworth, NJ.

AN OPEN LABEL PILOT STUDY TO EVALUATE THE EFFICACY OF LYMPHOBLASTO1D INTERFERON (L-IFN) 1N PATIENT WITH CHRONIC HEPATITIS C PREVIOUSLY TREATED WITH RECOMBINANT ALPHA- INTERFERON (R-IFN). J.P. Martinet, L. Spahr, D. Murphy, M. Petrella, A. Vachereau, B. Wfllems. Centre de recherche clinique Andr6-Viallet, H6p.St-Luc, Univ. of Montreal, Laboratoire de Sant6 Publique du Quebec and Burroughs Wellcome Canada Inc, Canada.

In the treatment of chronic hepatitis C patients, it has been recently suggested that patients who did not respond to R-IFN may have a sustained response to L- IFN (J Hepatol 1991; 13:419). Patients and methods: To evaluate this,we conducted an open label pilot study in 10 patients with documented chronic hepatitis C who had been previously treated with R-IFN and who either failed to respond (NR)(n=9) or had a transient response with breakthrough serum ALT during treatment (BT)(n= 1). They were 9 male,1 female,mean age 44.2 yrs (29- 55),with chronic hepatitis (n =5),complicated by cirrhosis (n=5). Mode of conta- mination was former IV drug addiction in 5 and unknown in 5.Viral genotype was type 1 in 7 patients,type 2 in 2 patients and type 4 in one patient.They were assigned to receive L-IFN 3 MUI sc tiw for a one year period.If serum ALT did not normalize after 8 weeks of therapy,dosage was increased to 6MUI s.c. tiw.If ALT was not normal after 8 weeks of 6 MUI regimen,treatment was stopped. Serum HCV RNA and genotypes were detected at baseline and when the treatment was stopped, by the technique previously described (Murphy et al, JID 1994,169: 473).Efficacy endpoints were normalization of ALT and absence of HCV RNA at the end of treatment.Results: After a mean duration of therapy of 18.2 weeks (11-32),all patients had their medication stopped.Eight patients were NR, 1 had a BT response and, in 1 patient, ALT was normal the day treatment was stopped for severe side effect (SE) but again abnormal 2 weeks after.HCV RNA remained positive in all the 10 patients.Viral genotypes did not change. Two patients had their treatment stopped because of incapacitating fatigue ( n = l ) and severe psychiatric manifestation(n= 1).Minor side effects usually encountered with IFN therapy subsided upon cessation of treatment (expressed as mean+SEM, # = NS) N = 10 Pretreatment end of treatment ALT (U/L) 161.5 +_ 31.7 130.1 _+ 30.7# Positive HCV RNA 10 10 Patient status to previous IFN therapy 9 NR, 1 BT 8 NR,1 BT,1 SE Conclusions: In this study, L-IFN was generally not effective in normalizing ALT values and no patient lost HCV RNA. Viral parameters such as genotype and viral load or neutralizing antibodies to IFN may have played a role. Further studies may be warranted in selected patients.

P R O D U C T I O N O F I N T E R F E R O N - , . , BY L I V E R A N D P E R I P H E R A L B L O O D T - L Y M P H O C Y T E S IN P R I M A R Y S C L E R O S I N G C H O L A N G I T I S . Eduardo B Martins. Roge r W Chapman, Kenne th A Fleming. Dept. of Gastroenterology and Nuffield Dept. of Pathology, John Radcliffe Hospital, Oxford, UK.

The genesis of pr imary sclerosing cholangitis (PSC) is unknown, but autoimmunity has been suggested. So far little is known about the cytokine profile in PSC, in particular the role of interferon-~/(IFN-~t), a cytokine of the T h l type, wh ich is involved in cell mediated immuni ty . A i m : To invest igate the cytokine profile of l iver der ived and peripheral b lood lymphocy tes in PSC. Materia ls and methods: 10 PSC patients were studied. L ive r der ived lymphocytes (LDL) were obtained by collagenase digestion of fresh liver biopsies. Peripheral blood lymphocytes (PBL) were obtained at the same t ime by gradient ceutrifugation. Cytokine production at the individual cell level was assessed by the reverse hemolytic plaque assay. Cell suspensions were incubated on a monolayer o f protein-A conjugated sheep erythrocytes with the appropriate polyclonal anti-cytokine serum (IFN-~/, TNF, IL-2 and IL-4). The reaction was developed using c o m p l e m e n t , with a r ing of hemolys is fo rmed around the cytokine secreting cells (CSC) whose phenotype was subsequently determined by immunocytochemis t ry . The area of hemolysis was measured to quant i fy the cy tok ine product ion . Resu l t s : 6/10 PSC had detec table IFN-7 sec~'etion by LDL, and 3 of these 6 had detectable IFN-y secretion by PBL. IFN-~t was secreted by PBL but not L D L in 1 patient. L D L secreted TNF-~t in 1 patient and IL-4 in another, both also positive for IFN-'~. The cytokine production (assessed by hemolysis area) was higher in L D L than PBL (p=0.005). On i m m u n o e y t o c h e m i s t r y the IFN-y secreting cells we re ac t iva ted ~l 3 T - l y m p h o c y t e s (CD3 ÷, TcRctl3 ÷, H L A - D R +, CD68-). Conclus ion: In PSC, the secretion of the p ro - in f l ammato ry cy tok ine IFN-~' by act ivated l iver and peripheral blood T-cells is up-regulated, suggest ing a T h l profi le in this condition. Moreover the production o f IFN-~, is higher by L D L than by PBL. These results confirm an important role of the L D L in the pathogenesis of PSC which may be in part mediated by IFN-y.