Marion Peters

Randomized, controlled trial of recombinant human α-interferon in patients with chronic hepatitis B

Forty-five patients with chronic hepatitis B were entered into a randomized controlled trial of recombinant human alpha-interferon therapy. All patients had hepatitis B surface antigen in serum for at least 1 yr and had stable serum levels of both hepatitis B virus deoxyribonucleic acid and hepatitis B e antigen. During the 4-mo period of therapy, 10 of 31 (32%) treated patients and only 1 of 14 (7%) control patients became negative for serum hepatitis B virus deoxyribonucleic acid and deoxyribonucleic acid polymerase. All 10 patients who became negative for serum hepatitis B virus deoxyribonucleic acid subsequently had a marked improvement in serum aminotransferase activities and lost hepatitis B e antigen from serum, and 9 of them had improvement in liver histology. Comparison of responders to nonresponders indicated that female sex and a high initial level of serum aspartate aminotransferase correlated best with response to interferon therapy. These findings indicate that a 4-mo course of recombinant alpha-interferon can induce a remission in disease in approximately one-third of patients with chronic hepatitis B.

Randomized trial of chlorambucil for primary biliary cirrhosis

Twenty-four patients with primary biliary cirrhosis were entered into a prospective, randomized trial of chlorambucil therapy. Thirteen patients received chlorambucil (0.5-4 mg/day) and 11 patients received no therapy; all have been followed for 2-6 yr (mean, 4.1 yr). Two control but no treated patients died. Average serum bilirubin, serum aspartate aminotransferase activities, and albumin levels improved or remained unchanged in treated patients but worsened in controls. Serum alkaline phosphatase levels did not change in either group. Immunoglobulin M levels decreased and became normal in all treated patients but in only 3 control patients. Liver biopsy histology revealed an improvement in inflammatory cell infiltrate in treated patients in comparison with controls, but no significant change in degree of fibrosis or the histologic stage of disease. Side effects of therapy included bone marrow suppression necessitating discontinuation of the drug in 4 patients. These findings indicate that chlorambucil therapy may retard the progression of primary biliary cirrhosis. Whether such therapy will ultimately decrease morbidity and improve survival in this disease can only be demonstrated by large-scale, placebo-controlled trials.

Pilot study of recombinant human α-interferon for chronic type B hepatitis

Nine patients with chronic type B hepatitis were entered into a preliminary study of recombinant, human alpha-interferon therapy. Patients received one to four courses of interferon, each consisting of a fixed dose of 18, 36, 50, 68, or 100 million units given three times a week for 2 wk. Side effects including fever, chills, fatigue, myalgias, headache, and neutropenia were common and especially severe with higher doses. Serum hepatitis B virus DNA polymerase activity fell during therapy to 15%-30% of the pretreatment levels irrespective of interferon dose, but rose to the initial level by 10 days after the course ended. During follow-up, 2 patients had a sustained clinical remission in which hepatitis B virus DNA, DNA polymerase, and hepatitis B e antigen disappeared from serum and amino-transferase activities fell to normal. One patient became hepatitis B surface antigen negative. We conclude that higher doses (50 and 68 million units) of interferon have greater side effects than lower doses (18 and 36 million units), without having any greater antiviral efficacy. Further studies should be directed at therapy with lower doses given over longer periods.

T cell enrichment and depletion of human peripheral blood mononuclear cell preparations. Unexpected findings in the study of the functional activities of the separated populations

Abstract In the present communication we present the results of a study undertaken to assess the effectiveness of several methods of depleting human peripheral blood of thymus-derived (T) cells, and to assess the purity of the T cell-enriched populations obtained. The methods of T cell depletion employed included rosetting with unmodified sheep red blood cells (SRBC) in the cold at high erythrocyte to lymphocyte ratios; rosetting with S-2-aminoethylisothiouronium bromide hydrobromide (AET)-treated SRBC; and cytotoxic depletion using anti-Leu-1, a monoclonal antibody directed toward a pan-T cell antigen, and rabbit complement. The methods used to enrich for T cells included rosetting with unmodified or AET-treated SRBC, and passage through a nylon wool column. • The purity of the T-enriched and T-depleted populations obtained was assessed by (a) repeat rosetting with unmodified SRBC, (b) staining for cell surface immunoglobulin (sIg), (c) quantitating the number of Ig secreting cells (ISC) in a reverse hemolytic plaque assay, (d) quantitating the proliferative responses to the T cell mitogens phytohemagglutinin (PHA), concanavalin A (Con A) and pokeweed mitogen (PWM) and to the B cell mitogen Staphylococcus aureus Cowan (SAC), and (e) quantitating the development of ISC following culture with PWM, with or without the addition of an irradiated T cell-enriched population. • By all parameters investigated, the depletion of T cells from peripheral blood by rosetting with AET-treated SRBC or by treatment with anti-Leu-1 and complement was far more effective than by rosetting with unmodified SRBC under optimal conditions. Of particular note was the finding that functional assays (ISC at time zero (T0), proliferative response to SAC, the development of ISC on culture with PWM) revealed a much higher degree of B cell contamination in all of the T cell-enriched populations than would have been suspected from the extent of the depletion of sIg staining cells.

Randomized Controlled Trial of a Four Month Course of Recombinant Human Alpha Interferon in Patients with Chronic Type B Hepatitis

Chronic infection with hepatitis B virus (HBV) is major cause of chronic hepatitis, cirrhosis and hepatocellular carcinoma world-wide (1). No therapy has yet been proven to be of definite benefit in improving the natural outcome of this infection. The most promising modality of treatment for this condition has been prolonged courses of alpha interferon (IFNα) (2,3). Other agents have either not been successful in achieving the aims stated above or have resulted in unacceptable side effects (4,5). In pilot studies, treatment of chronic type B hepatitis with IFNα has been shown to result in a response rate of between 22–40% (6,7). We undertook a randomized controlled trial of a four month course of recombinant human IFNα (rIFNα) in patients with chronic type B hepatitis.

Antigen-specific human B-cell responses: Modulation by immunoregulatory T-cell subsets

In vitro T-cell requirements for and modulation of human B-cell responses were studied in individuals immunized in vivo to the protein antigen keyhole limpet hemocyanin or tetanus toxoid. T cells were required for antibody synthesis in both antigen-driven and pokeweed mitogen (PWM)-driven cultures. T cells were separated into T4+ and T8+ subpopulations using monoclonal antibodies, and their modulation of antibody synthesis was studied. T4+ cells functioned as helper cells in both antigen-driven and PWM-driven cultures in a dose-dependent manner. Whereas T8+ cells suppress both total and specific immunoglobulin secretion in PWM-stimulated cultures, in antigen-stimulated cultures T8+ cells do not suppress unless activated by another cell population present in peripheral blood mononuclear cells (PBMNC). This cellular requirement was further investigated by prestimulation of cells prior to addition to optimally stimulated antigen-driven cultures of PBMNC or B cells, monocytes, and helper T cells. No suppression of these optimally stimulated cultures was seen when T8+ cells were precultured with antigen or PWM. However, after 3-5 days preculture of total T cells with PWM or antigen and then selection of T4+ cells, these cells were able to induce fresh autologous T8+ cells to suppress optimally stimulated antigen-driven cultures. Addition of a precultured mixture of T8+ cells with 20% T4+ cells also resulted in antigen-induced suppression. These data indicate that T8+ cells can suppress antigen-driven cultures but require the presence of preactivated T4+ cells for induction of this suppression of antigen-specific T-cell-dependent human B-cell responses.