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Biomedical subjects

S Kojima

Publications and source records attributed to S Kojima.

At least 1,063 records · Page 59Linked to original sources
PubMed1977

Tolerizing effect of DNP-ficoll on IgE antibody production.

A/J and DBA/1 mice were infected with 750 third-stage larvae of Nippostrongylus brasiliensis and immunized with 1 mug dinitrophenylated N. brasiliensis extract (DNP-Nb) with 1 mg Al(OH)3 to produce high titers of anti-hapten IgG1 and IgE antibody. Partial tolerance to the production of anti-hapten IgG1 and IgE antibody could be induced by DNP-Ficoll from 5 weeks before to 1 week after the DNP-Nb immunization. The tolerized state persisted through the duration of the experiments. However, no tolerizing effect could be demonstrated on secondary antihapten IgE antibody production induced by DNP-Nb. Moreover, DNP-Ficoll failed to evoke anti-hapten IgG1 or IgE antibody production.

Animals↗
PubMed1977

Suppression of IgE antibody production in SJL mice. II. Expression of Ly-1 antigen on helper and nonspecific suppressor T cells.

Under appropriate conditions of immunization combined with irradiation, SJL/J mice show a high and persistent anti-DNP IgE antibody response. Spleen cells transferred from normal untreated SJL mice suppress this response. Elimination of Ly-1+ cells, but not of Ly-2+ cells, abolished the capacity of spleen cells to suppress the IgE response. Thus of the three T cell Ly subclasses presently identified, Ly-1, Ly-2,3, and Ly-1,2,3, the normal SJL spleen cell which suppresses the IgE response of irradiated-immunized SJL mice belongs to the Ly-1 set. It is not known whether this Ly-1 cell suppresses the IgE response directly or by helping another cell in the recipient. The carrier-specific helper cell activity for IgE and probably IgG1 antibody response belongs to Ly-1 subclass in the SJL strain also.

Animals↗
PubMed1976

Suppression of IgE antibody production in SJL mice. I. Nonspecific suppressor T cells.

High titer and persistent antihapten IgE production in SJL mice can be obtained using appropriate immunization and radiation. Nonirradiated mice rapidly terminate this antihapten IgE production. Radiation was not necessary to prolong antihapten IgE production in other strains of mice. Termination can be obtained even in irradiated SJL mice by transferring normal SJL spleen cells. That the suppressor cells are T cells is shown by using thymocytes or cells treated with anti-Thy 1.2 and complement. No appreciable suppressive effect by normal spleen cells could be demonstrated on IgG1 production in SJL mice. The characteristic of low and transient IgE antibody response in SJL mice is inherited as a recessive trait controlled by a single Mendelian autosomal gene and is not linked to the H-2-gene complex. This characteristic does not depend on the infectivity of Nippostrongylus brasiliensis, the effect of anticarrier antibody, or the recognition of antigen.

Animals↗
PubMed1976

Effect of cholesterol sulfate and sodium dodecyl sulfate on lecithin-cholesterol acyltransferase in human plasma.

The effects of cholesterol sulfate and sodium dodecyl sulfate (SDS) on the esterification of cholesterol in sonicated dispersions of lecithin-cholesterol mixtures by lecithin-cholesterol acyltransferase [EC 2.3.1.43] (LCAT) in human plasma were studied in vitro. The acyltransferase activity was inhibited at concentrations of cholesterol sulfate higher than 1 X 10(-4) M. This inhibition was not eliminated by the addition of bovine serum albumin or CaC12. On the contrary, the acyltransferase activity was stimulated at concentrations of SDS ranging from 1 X 10(-5) M to 1 X 10(-3) M, and maximum stimulation was obtained at 5 X 10(-4) M. The maximum stimulation disappeared on the addition of bovine serum albumin (30 mg per ml of incubation medium), 1 X 10(-3) M CaC12 or 1 X 10(-4) M cholesterol sulfate. On the other hand, the extent of inhibition of the acyltransferase by cholesterol sulfate was not affected by the amount of lecithin in the dispersion added as a substrate, but the maximum stimulation (5 X 10(-4) M SDS) of the acyltransferase was interfered with when a large amount of lecithin was present in the dispersion. In addition, the amount of SDS required for maximum cholesterol esterification was not affected by the amount of lecithin present in the dispersion. These results suggest that the action of cholesterol sulfate on the acyltransferase is different from that of SDS.

Acyltransferases↗
PubMed1976

Carrier effect by Nippostrongylus brasiliensis infection on rat antihapten IgE antibody response.

Nippostrongylus brasiliensis infection was found to be highly effective in inducing a carrier-specific enhancing effect on primary and secondary antihapten IgE antibody response in the rat, when animals were immunized i.p. with 10 mug of dinitrophenylated N. brasiliensis protein (DNP-Nb) plus 10 mg Al(OH)3 2 weeks after the infection. The carrier effect by the infection was much greater than that obtained by any other supplementary immunization with the carrier (Nb) plus adjuvant, so far examined, in terms of the IgE antibody response. The results, together with our previous observation in the mouse, provide an explanation for the reason why antiworm IgE antibodies are so easily detectable in helminth infections.

Ancylostomatoidea↗
PubMed1976

Characteristics of guinea pig IgE.

Anti-dinitrophenyl (DNP) IgE antibody was produced in guinea pigs (GP) by immunization and repeated boosters with 1 mug DNP-Ascaris extract in A1 (OH)3. The isoelectric point was determined to be 6.48 and the molecular weight to be 185,000 daltons. In absorbtion chromatography, rabbit anti-GPIgG1 could not absorb the anaphylactic activity of the IgE. The activity of IgE was destroyed by heating at 56 degrees C for 1 h. IgE persisted in the skin for at least 3 weeks.

Animals↗