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Y Munakata

Publications and source records attributed to Y Munakata.

81 records · Page 5Linked to original sources

In vitro culture of thymic epithelial cells from various autoimmune diseases: its thymosin-like effect on human peripheral lymphocytes.

We succeeded in the culture of the thymic epithelium which obtained from the patients with various autoimmune diseases aged from 20 to 65 years whose thymuses should have already been involuted with decreased thymic function. The mean percentage of active rosette-forming cells significantly increased after the incubation with thymic monolayer culture medium. These observations suggest that thymic epithelia in autoimmune diseases produce thymosin-like factor(s) in culture medium.

Adult↗

gamma-Glutamyl transpeptidase activity in liver of alcoholics and its localization.

The activity and the histochemical localization of gamma-GTP in the liver of chronic alcoholics were investigated. Mean serum gamma-GTP activity in alcoholics was 542.5 +/- 337.9 milliunits/ml, and that of patients with nonalcoholic liver disease was 34.3 +/- 22.6 milliunits/ml. Hepatic gamma-GTP activity in alcoholics was significantly increased compared to that in control patients (15.62 +/- 9.29 versus 4.04 +/- 2.67 units/g of liver; p less than 0.001). A significant correlation was observed between hepatic and serum gamma-GTP activity. Light microscopically, a marked gamma-GTP activity was found in the bile canaliculi and a diffuse activity in the cytoplasm in alcoholic livers. By contrast, in the livers of nonalcoholic patients, only slight activity was observed in the bile canaliculi. The electron micrographs showed the enzyme was localized in the microvilli of both the bile canalicular and plasma membranes and the endoplasmic reticulum near the mitochondria in alcoholics. But a very low activity was demonstrated in the plasma membranes in the livers of nonalcoholic patients.

Bile Canaliculi↗

Rapid inhibitory effect of tacrolimus on T cell migration by suppressing CD29-related functions.

OBJECTIVE: To clarify the direct effect of Tacrolimus (FK506) on T cell function in relation to CD29. METHODS: Human T cell line H9 and phytohemagglutinin (PHA)-activated T cells were incubated with or without Tacrolimus. The cells underwent cell migration assay by using fibronectin-coated trans-wells, and at the same time the degree of adherence by cultured cells to fibronectin-coated plastic wells was measured. For H9 cells, intracellular filamentous actin formation and the cell surface expression of CD3, CD11a, CD25, CD26, CD44, CD29 were measured by using flow cytometry. Intracellular tyrosin-phosphorylation induced by fibronectin by CD29 stimulation in H9 cells was analyzed by immunoblotting. RESULTS: The ability of H9 cells and PHA-activated T cells incubated with Tacrolimus for 2 hours (hrs) to migrate and to adhere to fibronectin was significantly suppressed. However, the inhibiton was transient, because the ability of cells incubated with Tacrolimus for 24 hrs to migrate was not affected despite the suppression of cell replication. Tacrolimus showed slight but significant reduction of cell surface expression of CD29 within 4 hrs, but CD3, CD11a, CD25, CD26 and CD44 were not affected. Tacrolimus rapidly inhibited intracellular filamentous actin formation; the maximum inhibition was within 2 hrs and the effect was not observed at 6 hrs. Intracellular tyrosin-phosphorylation induced by CD29 stimulation was also inhibited by, Tacrolimus in H9 cells. CONCLUSION: Tacrolimus appeared to have transient early phase inhibitory effects on CD29-related function that may be associated with T cell migration.

Cell Adhesion↗