16. Section for Studies on Host-immune Response

Research conducted in the Section for Studies on Host-Immune Response has focused on fundamental studies and clinical applications of immunological mechanisms, aimed at developing therapeutic strategies for malignant diseases.

Establishment of Monoclonal Antibodies Recognizing Intermediate TCR Cells in Various Mouse Strains

By immunizing a murine lympho-ma cell line, tMK-2U derived from intermediate TCR (TCR^int) cells of the BALB/c nude mouse, the U5A2-13 monoclonal antibody (mAb) was established. U5A2-13 Ag was found to be expressed on 65% of TCR^int cells and 55% of hepatic NK cells in a broad spectrum of mouse strains including both NK1.1⁺ and NK1.1^-. The total disappearance of U5A2-13⁺TCR^int cells from the livers of MRL/lpr mice after the onset of the autoimmune disease was observed, whereas approximately 30% of IL-2Rb⁺TCR^int cells remained. Furthermore, according to the stage of pregnancy, U5A2-13⁺TCR^int cells apparently increased from 0 to 7.5% in the uteri of BALB/c mice, whereas the proportion of IL-2Rb⁺TCR^int cells remained unchanged (approximately 8%). These results show clearly that the U5A2-13 mAb recognizes a population very similar to NKT cells, in various mouse strains, but has molecules different from the NK1.1 antigen. We believe that U5A2-13 mAb is potentially a very useful and highly effective tool for studies on the different functions of TCR^int cell subsets, since it is capable of identifying the heterogeneity among TCR^int cells.

Elevated Serum Thioredoxin Level in Patients with Chronic Gastritis

The serum level of thioredoxin (TRX) was markedly increased in patients with chronic gastritis as compared with that of normal volunteers, and the increase was statistically significant. Furthermore, it was found that the serum TRX level was higher in patients with severe atrophic gastritis than in those with mild atrophic gastritis, but the difference was not statistically significant. When gastritis due to Helicobacter pylori infection was improved by abolishing H. pylori using anti-microbial drugs, the elevated serum TRX level normalized. These observations suggest that the serum TRX level is a useful marker of chronic gastritis and also a potential marker of hepatocellular carcinoma, as was described last year.

List of papers from this division is not available

Table of Contents