Hideo Miyakoshi

Improvement of Gelatin Particle Agglutination Test for Detection of Anti-HTLV-I Antibody

Partial modifications of antigen components were made to improve the gelatin particle agglutination (PA) test for the detection of antibodies against human T cell leukemia virus type‐I. Envelope glycoproteins prepared by lentil lectin affinity chromatography were further added to the purified viral antigens to be coated on the gelatin particles. Comparative studies with a conventional PA test kit (Serodia ATLA) and indirect immunofluorescence assay showed that the specificity and sensitivity of the new PA test were increased and that abnormal agglutination such as the prozone phenomenon was abolished by this improvement.

Acting mechanisms of Lentinan in human--I. Augmentation of DNA synthesis and immunoglobulin production of peripheral mononuclear cells.

The immunopotentiating activity and acting mechanisms of Lentinan were investigated in the human system, resulting in clarification of the following characteristics. (a) Augmentation of DNA synthesis of peripheral mononuclear cells (PMNC) occurred both in vitro and in vivo by adding or injecting Lentinan, for which the coexistence of T cells, B cells and adherent cells (mainly monocytes) was essential. (b) No additional mitogenic effect of Lentinan was observed when PMNC were incubated with both Lentinan and other mitogens. (c) In vitro production of immunoglobulin by PMNC induced with pokeweed mitogen was enhanced through the inhibition of suppressor T cell activity by Lentinan.

INTERACTION BETWEEN INTERFERON AND NATURAL KILLER CELLS IN HUMANS AFTER ADMINISTRATION OF IMMUNOMODULATING AGENTS

Publisher Summary This chapter focuses on interaction between interferon and natural killer (NK) cells in humans after administration of immunomodulating agents. In a styudy described in the chapter, NK activity was readily enhanced, following an increase in the interferon (IFN) titers by Lentinan administration, whereas no significant activation of NK cells was observed even when IFN titers were elevated by Staphage Lysate (SPL) administration. International units of IFN in the body fluid were determined by measuring its inhibitory activity against cytopathic effects of vesicular stomatitis virus (VSV). By sequential measurements of NK activity and IFN titers after Lentinan administration, the peaks of IFN appeared at 12–24 h and NK activity gradually increased in inverse proportion to a decrease in IFN titers, peaking at 24–48 h. To interpret dissociation between the peaks of IFN titers and NK activity, it would be one possible explanation that IFN-activated NK cells gathered and infiltrated into the malignant tissues just after the IFN production by Lentinan administration, resulting in no detection of effective NK cells in the peripheral blood. It seems most likely that this IFN or IFN-like substance produced by SPL affects virus replication but does not activate NK cells.