Biomedical subjects

H Sadakata

Publications and source records attributed to H Sadakata.

3 recordsLinked to original sources

PubMed1991

Tissue factor released from leukemic cells.

Using clotting assay and radioimmunoassay (RIA), tissue factor activity (TFA) and TF related antigen (TFR:AG) were determined in an extracellular culture medium of HL-60 cells. After 12 h incubation, TFA and TFR:AG in the medium with endotoxin (EDX: 1 microgram/ml) reached maximums which were 1.8 and 2.1 times greater than those in the medium without EDX, respectively. In the leukemic cells of 10 patients with acute nonlymphoid leukemia (ANLL), TFR:AG showed a significant correlation with TFA (p less than 0.01). On day 1 of the induction chemotherapy, TFR:AG in the 7 patients with DIC significantly increased to 288.9 +/- 153.1 ng/ml (p less than 0.01), whereas no increase in TFR:AG was recognized in the 3 patients without DIC. These results suggest that TF may be released from leukemic cells into the culture medium or blood stream, and that this may correlate with the development of DIC.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed1990

One-stage method for assay of tissue factor activity of leukemic cell with special reference to disseminated intravascular coagulation.

Tissue factor activity (TFA) of leukemic cells (1 x 10(8) cells/mL) was measured in 44 patients with acute nonlymphoid leukemia (ANLL) by the one-stage assay using factor-IX deficient plasma (OSA-dIX) and two-stage assay (TSA). According to the preventative heparin dose schedule based on the TFA measured by the TSA, all disseminated intravascular coagulation (DIC) was controlled successfully. The procedure of the TSA was too complicated for clinical use, and its minimal measurable value was 125 units (U)/L of TFA. The OSA-dIX was simpler in its procedure and sensitive enough to measure accurately a TFA quantity as small as 30 U/L with high reproducibility. In 20 ANLL patients with 125 U/L or more of TFA measured by both assays, there was a significant relationship between their logarithms of TFA (r = 0.93, P less than 0.01). These results suggested that DIC complication in ANLL patients would be controlled successfully by the administration of heparin dosage based on the TFA measured by the OSA-dIX.

Adult↗

PubMed1989

Studies on leukemic cell tissue factor.

Apoprotein part of tissue factor of human placenta was purified 871 fold from the starting material with 4.2% yield by concanavalin A-Sepharose affinity chromatography and SDS-PAGE. The molecular weight of purified apoprotein was 45,000 in non-reduced condition and 49,000 in reduced condition. Tissue factor of human leukemia cells (FAB classification:M2 and M3) and cultured leukemia cell lines (HL-60 and Molt-4) was analyzed using specific rabbit anti-tissue factor IgG raised against purified material. Endotoxin stimulated HL-60 and Molt-4 also expressed procoagulant activity which was inhibited by tissue factor immune IgG. By immunostaining of the purified material, the lysate of leukemia cells (M2 and M3) and cultured leukemia cells (HL-60 and MOLT-4) revealed a major band of the same apparent molecular weight. Immuno-electron microscopic study on tissue factor of HL-60 cells produced the following findings: stimulation by endotoxin resulted in the formation of pseudopods of the cell membrane, and immunogold particles accumulated mainly on these pseudopods and cisternal spaces of rough endoplasmic reticulum, indicating exposure of the tissue factor to the surface of perturbed cell membrane with concurrent increase in tissue factor synthesis.

Antibody Formation↗