Tatehiro Kagawa

Establishment of a human cell line (HCC-T) from a patient with hepatoma bearing no evidence of hepatitis B or A virus infection

A human hepatoma cell line, designated HCC‐T, was established. The tumor was surgically obtained from a Japanese male patient with hepatocellular carcinoma (HCC) arising in a cirrhotic liver that had supposedly developed from nonAnonB (NANB) chronic hepatitis. HCC‐T exhibited a typical morphology of epithelial cells in culture. Population doubling time was 24 hours and HCC‐T cells had characteristics of malignant cells demonstrated by the ability to grow in a soft agar medium and transplantability to nude mice. The histologic condition of the tumor transplanted to a nude mouse showed similarity to the original tumor. A chromosome analysis showed that there were ten identifiable marker chromosomes and sex chromosomes with its modal number of 64. Alpha‐fetoprotein (AFP) production was demonstrated by direct immunofluorescence study, but albumin or hepatitis B surface antigen were not detectable. The integration of hepatitis B viral DNA was not demonstrable in the genome of HCC‐T cells or the original hepatoma.

A randomized, controlled trial of weekly administration of lymphoblastoid interferon in patients with chronic hepatitis C

To evaluate the efficacy of a treatment of weekly interferon administration in patients with chronic hepatitis C, 36 patients were randomly assigned to two groups. In one group lymphoblastoid interferon was given at a dose of 6 million units, intramuscularly, once per week for 24 weeks, and no treatment was given to the other. Serum alanine aminotransferase levels in the treated group were significantly lower during therapy than in the control group, although there was no significant difference between these two groups before therapy. The normalization of serum alanine aminotransferase levels at the end of therapy was observed in 50% of the treated group, and in 11.1% of the control group. This difference was statistically significant (p < 0.03). Response to interferon was better in patients with chronic persistent hepatitis or with chronic active hepatitis than in patients with chronic active hepatitis with cirrhosis. Relapse after the end of therapy was observed in 83.3% of the responders. These results indicate that the weekly administration of 6 million units of lymphoblastoid interferon is effective in decreasing serum alanine aminotransferase levels in patients with type C chronic persistent hepatitis or chronic active hepatitis.

Antibody-dependent cell-mediated cytotoxicity against cell lines generated by liver-specific idiotype-bearing antibody

We produced a murine monoclonal antibody (mAb), designated H2-mAb, against a fractionated soluble phase of human liver homogenate which antibody reacted with human liver cells. A human antibody possessing the same idiotype as the H2-mAb, designated LSIA (liver-specific idiotype-bearing antibody), can be measured by a sandwich enzyme-linked immunosorbent assay, using the anti-H2 idiotype antibody. The serum level of LSIA in patients with histologically proven chronic hepatitis (CH) was significantly higher than that in healthy subjects and it was also higher than that in subjects with other diseases, including systemic lupus erythematosus. In a comparison between patients with CH type B and those with CH type C, there was no significant difference in serum levels of LSIA. It was possible to purify LSIA from the sera of patients with CH. The purified LSIA bound to the human cell lines Chang and HCC-M, derived from liver cells and a hepatoma respectively, but not to HeLa cells, a uterine carcinoma derivative. The reactivity of this mAb to HCC-M was weaker than that to Change. Moreover, the presence of LSIA caused an antibody-dependent cell-mediated cytotoxic challenge against Change cells in vitro.

Changes in high mannose-type glycoproteins of peripheral blood mononuclear cells in cirrhosis patients

Abstract Glycoproteins of peripheral blood mononuclear cells (PBMC) in patients with liver cirrhosis (LC) have not yet been studied. In the present study, we investigated high mannose-type glycoproteins of PBMC from patients with LC. We showed that [2- 3 H]mannose uptake by PBMC and binding of glycoproteins from PBMC to concanavalin A (Con A)-Sepharose were significantly lower in patients with LC than in healthy subjects. These results indicate that high mannose-type glycoproteins of PBMC are decreased in patients with LC. High mannose-type glycoproteins play an important role in the formation of functional high-affinity interleukin-2 (IL-2) receptors. Thus, the decrease of high mannose-type glycoproteins may be one of the factors affecting the function of T or natural killer (NK) cells, which require IL-2 receptors to exert various immunological functions, in patients with LC.

Treatment of chronic hepatitis C with weekly administration of interferon-α

SummaryTo evaluate the efficacy of weekly administration of interferon (IFN)-α, we studied 23 anti-HCV positive patients with chronic hepatitis diagnosed by liver needle biopsy. Thirteen patients received weekly intramuscular injections of 6 MU human lymphoblastoid interferon (HLBI) for 24 weeks, and the other 10 patients were given no treatment. We examined liver-specific idiotype-bearing antibody (LSIA) in the patients’ sera. This HLBI treatment was easily tolerated by all the treated patients. In the treated group serum alanine aminotransferase (ALT) level significantly decreased during HLBI treatment. Normalization of serum ALT level by the end of treatment was observed in 7/13 (54% ) of the treated patients but in 0% of the non-treated patients. Anti-HCV was detectable in all the patients during the treatment. Those who had high LSIA levels did not respond to HLBI treatment. These results demonstrate that weekly administration of IFN is sufficient to suppress disease activity in patients with chronic hepatitis C and that patients with high LSIA levels are unlikely to respond to IFN therapy.

Effect of interferon-β on in vitro production of the liver specific idiotype-bearing antibody in patients with chronic hepatitis B

Recently interferon (IFN) has been used for the treatment of patients with chronic hepatitis (CH) B. It is known that IFN-β has an anti-viral effect, but clinical effect of IFN-β is limited. In Japanese cases of type B CH, complete eradication of hepatitis B virus (HBV) can not be achieved, however, partial suppresion of viral replication is possible. On the other hand, IFN-β has also an immunopotentiating effect. To analyze the effect of IFN-β on immune reactions to HBV and autoimmune reactions in patients with type B CH is thought to be important.

Ammonium and α-mannosidase are key factors determining natural killer (NK) activity in patients with liver cirrhosis

Natural killer (NK) cells are a group of lymphocytes which destroy in vitro a variety of tumor cells in a nonselective way. The serum α-mannosidase activity was significantly higher in patients with liver cirrhosis (LC) than healthy subjects. α-mannosidase inhibited NK activity in vitro at low concentrations comparable to the serum level. NK activity was demonstrated to be directly proportional to serum ammonia level in patients with LC. These results suggest that α-mannosidase and ammonium are key factors determining NK activity in patients with LC.

Cellular cytotoxicity induced by liver specific idiotype-bearing antibody against Chang liver cells

Liver-specific idiotype-bearing antibody (LSIA) was capable of being purified from the sera of patients with chronic hepatitis by affinity chromatography. It was demonstrated that LSIA bound to Chang liver cells and induced ADCC. It is suggested that ADCC induced by LSIA is related to liver cell damage in patients with chronic hepatitis (CH).