PubMed Health⌕ Search

Biomedical subjects

A Kosaka

Publications and source records attributed to A Kosaka.

At least 73 records · Page 4Linked to original sources
PubMed1982

Acquisition of graft-versus-host reactivity by immature thymocytes in the coexistence of activated macrophages.

The collaborative role of macrophages in the acquisition of the rat graft-versus-host (GVH) reactivity by parental thymocytes was investigated by the popliteal lymph node enlargement assay. The addition of peritoneal macrophages activated by streptococcal bacteria injection resulted in significantly increased GVH reactivity of parental thymocytes, when assayed both in normal F1 hybrid hosts and in those depleted of effective macrophages and lymphocytes. The thymocytes that acquire that alloantigen reactivity in the presence of activated macrophages were shown to be cortisone sensitive and of high density. Hence, the cortisone-resistant and less dense population of thymocytes did not exhibit further reactivity even in the presence of macrophages; however, this subpopulation showed an enriched activity on its own. Moreover, the simultaneous injection of activated macrophages induced a further augmenting effect on the graft-versus-host reaction (GVHR) of freshly peripheralized thymocytes, but did not affect the reactivity of lymph lymphocytes from parental rats thymectomized 15 months previously. These data suggest that activated macrophages play an essential role in the acquisition of alloantigen reactivity by immature thymocytes, and also that the macrophage-dependent thymocytes in the reaction may reside among the subpopulation that is cortisone sensitive, highly dense, short-lived, and freshly peripheralized. The possible nature of immunological maturation of immature thymocytes in the periphery is discussed in relation to cellular interactions with activated macrophages.

Animals↗
PubMed1982

[Effect of lentinan administration of adrenalectomized rats and patients with breast cancer].

To investigate a clinical application of Lentinan, an immunomodulator and polysaccharide extracted from Lentinus edodes, an effect of Lentinan on the adrenalectomized rats was examined. The multiple injection of Lentinan did not result in any changes in the growth curves, survival rate nor histamine sensitivity, compared with those of the controls, indicating that Lentinan might be a useful agent in the combination therapy of adrenalectomized animals. The clinical safety of Lentinan administration for the patients with advanced or recurrent breast cancer who received bilateral oophorectomy and adrenalectomy were confirmed, and its efficacies were evaluated by prolongation of life span and antitumor effect. The improvement of prognosis was observed in Lentinan treated patients, compared with the control.

Adrenalectomy↗
PubMed1981

Enzyme immunoassay for antibodies in serum using a covalent chromatographic method for separation of the bound label.

A sensitive enzyme immunoassay system for the measurement of antibodies in serum was developed by the use of a separation method based on the thiol-disulfide interchange reaction. Serum samples including antibodies (anti-insulin, anti-human chorionic gonadotropin, or anti-beta-D-galactosidase) were incubated with antigens labeled with beta-D-galactosidase from Escherichia coli. Each reaction mixture was then passed through a small column (0.1 ml) of (anti-IgG)IgG-Sepharose 4B, in which the (anti-IgG)IgG had been coupled by means of a disulfide bond. The column was washed to remove the unbound label, then the antibody-bound label was eluted from the column with a buffer containing 25 mM dithiothreitol, which cleaved the disulfide bonds between the Sepharose matrix and the anti-IgG antibody molecules. By measuring the enzyme activity in the eluate, the amount of antibodies could be determined even in a serum sample which contained antibodies corresponding to as little as 0.01% of the standard antisera. Preliminary experiments showed that the present method can be used to detect the anti-insulin antibody in the sera from insulin-treated diabetic patients.

Animals↗
PubMed1981

Enzyme immunoassay for thyroxine and triiodothyronine in human serum, with use of a covalent chromatographic separation method.

A practicable enzyme immunoassay for measurement of thyroxine and triiodothyronine in serum was developed, involving a separation method based on the thiol-disulfide interchange reaction. Serum samples at alkaline pH were incubated for 1 h with antibodies and antigens labeled with beta-D-galactosidase. Each reaction mixture was then passed through a 0.1-mL column containing (anti-IgG) antibody immobilized on Sepharose 4B, to which the anti-IgG antibodies were coupled by means of a disulfide bond (3 g of IgG fraction per liter). The column was washed and the bound form of the label then was eluted from the column with a buffer containing dithiothreitol (25 mmol/L) by splitting the disulfide bonds between the anti-IgG antibody molecules and Sepharose matrix. From the enzyme activity in the eluate, concentrations of thyroxine or triiodothyronine in serum could be determined. Values obtained by this method and those obtained by a radioimmunoassay correlated well (thyroxine, r = 0.97, slope = 1.1 y-intercept = -0.94 microgram/L, n = 70; triiodothyronine, r = 0.98, slope = 0.91, y-intercept = 0.067 microgram/L, n = 77.

Chemical Phenomena↗
PubMed1980

Improved reaction buffers for solid-phase enzyme immunoassay without interference by serum factors.

A gelatin moderately digested by a protease, was as effective as original gelatin to remove the interference by serum factors with a sandwich immunoassay for insulin. Digestion of gelatin resulted in decrease in the viscosity, and the buffer containing the digested gelatin did not show gelation at 4 degrees C. Therefore the buffer involving the digested gelatin might be widely useful for the immunoassay without interference by serum factors.

Buffers↗
PubMed1980

Asialoglycoproteinemia in a case of primary hepatic cancer.

This article reports on a case with the most unusual finding of asialoglycoproteinemia. The patient was a man aged 40 years suffering from primary hepatic cancer. Among the various serum glycoproteins tested, the concentration of the desialylated form of alpha 2-HSglycoprotein, transferrin and alpha 2-antitrypsin was markedly elevated. The asialoprotein/sialoprotein ratio varied with each glycoprotein. In the case of transferrin, the ratio changed considerably in the course of the disease, and was found to be clearly related to the change in size of the hepatic tumor.

Asialoglycoproteins↗
PubMed1979

Evaluation of a solid-phase enzyme immunoassay for insulin in human serum.

We describe a "sandwich-type" enzyme immunoassay for insulin in serum, in which antibody Fab'-beta-D-galactosidase conjugate and an antibody-immobilized silicone rubber solid-phase are used. The interference by serum factors with the solid-phase enzyme immunoassay can now be removed by using a buffer containing gelatin. Serum samples of 50 microL can be analyzed by the enzyme immunoassay, which is as sensitive as radioimmunoassay for human insulin. Our results correlate well with those for radioimmunoassay (r = 0.97, slope = 0.92, y-intercept = 4.6 milli-int. units /L for 181 samples). Between-assay and within-assay coefficients of variation are less than 15% over the useful ranges of the assay (5--160 milli-int. units/L).

Evaluation Studies as Topic↗