Senwa Unten

Stimulation of granulocytic cell iodination by pine cone antitumor substances.

Antitumor substances (Fractions VI and VII) prepared from the NaOH extract of pine cone significantly stimulated the iodination (incorporation of radioactive iodine into an acid‐insoluble fraction) of human peripheral blood adherent mononuclear cells, polymorphonuclear cells (PMN), and human promyelocytic leukemic HL‐60 cells. In contrast, these fractions did not significantly increase the iodination of nonadherent mononuclear cells, red blood cells, other human leukemic cell lines (U‐937, THP‐1, K‐562), human diploid fibroblast (UT20Lu), or mouse cell lines (L‐929, J774.1). iodination of HL‐60 cells, which were induced to differentiate by treatment with either retinoic acid or tumor necrosis factor, were stimulated less than untreated cells. The stimulation of iodination of both PMN and HL‐60 cells required the continuous presence of these fractions and was almost completely abolished by the presence of myeloperoxidase inhibitors. The stimulation activity of these fractions was generally higher than that of various other immunopotentiators. Possible mechanisms of extract stimulation of myeloperoxidase‐containing cell iodination are discussed.

Effect of pine seed shell extract on rotavirus and enterovirus infections

An NH4OH extract from seed shell of Pinus koraiensis Sieb. et Zucc. inhibited infections of rotavirus and enterovirus in cultured rhesus monkey kidney MA 104 cells. Antiviral activity of the extract was attributable to interference with virus adsorption, rather than to inhibition of virus replication after adsorption.

Effect of cacao husk extract on human immunodeficiency virus infection

A sodium hydroxide extract from cacao husk inhibited the cytopathic effect of human immunodeficiency virus type 1 (HIV‐1) against HTLV‐1‐transformed T‐cell lines MT‐2 and MT‐4. It also inhibited syncytium formation between HIV‐infected and uninfected lymphoblastoid T‐cell line, MOLT‐4. The anti‐HIV activity was concentrated by membrane filter fractionation to a fraction with molecular weight of 100–300 KDa. Anti‐HIV activity of the extract was attributable to interference with the virus adsorption, rather than to inhibition of the virus replication after adsorption.

DNA synthesizing activity during induced differentiation in mouse myeloid leukemia (M1) cells

Mouse myeloid leukemia (M1) cells were induced to differentiate in vitro by treatment with dexamethasone. After 8 h of treatment, induction of phagocytic and lysozymic activities and depression of DNA synthesis started at the same time and proceeded irreversibly. DNA synthesis in the nuclear system reflected primarily DNA replication rather than repair and this activity declined during M1 cell differentiation.