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Biomedical subjects

J Yodoi

Publications and source records attributed to J Yodoi.

At least 307 records · Page 17Linked to original sources
PubMed1980

Regulatory role of IgE-binding factors from rat T lymphocytes. III. IgE-specific suppressive factor with IgE-binding activity.

Incubation with rat IgE of rat mesenteric lymph node cells obtained 8 days after infection with Nippostrongylus brasiliensis (Nb) resulted in the formation of soluble factors with affinity for IgE, i.e., IgE-binding factors(s). The factors were derived from T lymphocytes and were able to suppress an in vitro IgE response without affecting the IgG response. The minimum concentration of rat IgE for the induction of factor formation was 0.3 to 1.0 microgram/ml. Gel filtration of culture filtrates of the IgE-containing culture identified 2 components with IgE-binding activity; one component had a m.w. of between 10,000 and 20,000, and another component had a m.w. of between 25,000 and 50,000. Both factors could be purified by binding to IgE-Sepharose followed by elution at acid pH. Among the two IgE-binding factors, the lower m.w. component had the ability to suppress selectively the IgE response. In contrast to IgE-potentiating factor, which also had affinity for IgE, the IgE-suppressive factor failed to bind to lentil lectin Sepharose. Formation of IgE-specific suppressive factor was not limited to the lymphocytes obtained 8 days after Nb-infection. Incubation with IgE of lymphocytes obtained 4 wk after infection resulted in the formation of both IgE-specific suppressive factor and IgE-potentiating factor, and the activity of the suppressive factor was greater than that of the potentiating factor.

Animals↗
PubMed1980

Regulatory role of IgE-binding factors from rat T lymphocytes. IV. Formation of IgE-binding factors in rats treated with complete Freund's adjuvant.

Mesenteric lymph node (MLN) cells from rats treated with complete Freund's adjuvant (CFA) spontaneously released soluble factors, which have affinity for IgE (IgE-binding factors). The factors were purified by absorption of culture filtrates of the lymphocytes with IgE-Sepharose followed by elution at acid pH. Purified IgE-binding factors selectively suppressed IgE-forming cell response of DNP-ovalbumin-primed MLN cells to homologous antigen without affecting the IgG2 response. Fractionation of purified IgE-binding factors on lentil lectin-Sepharose showed that the majority of IgE-binding factors did not have affinity for lentil lectin, whereas a minor fraction was bound to the lectin-coupled beads. It was found that IgE-binding factors lacking affinity for lentil lectin suppressed IgE response, whereas those eluted from lentil lectin-Sepharose selectively enhanced IgE response. Serum of CFA-treated animals also contained both IgE-suppressive factor and IgE-potentiating factor, and the amount of the former factor was more than the latter. The source of IgE-suppressive factor is non-B lymphocytes. Depletion of Fc, receptor(+) lymphocytes in MLN cells from CFA-treated animals did not affect the formation of IgE-suppressive factor, indicating that Fc epsilon R-bearing cells are not the source of the factor.

Animals↗
PubMed1980

Induction of Fc epsilon-receptor bearing cells in vitro in human peripheral lymphocytes.

Fc epsilon R-bearing lymphocytes were induced in vitro by the culture of peripheral lymphocytes from ragweed-sensitive patients with antigen E together with, or followed by, human IgE. Neither antigen E alone nor IgE alone induced Fc epsilon R(+) cells. As expected, culture of normal lymphocytes with the antigen and IgE failed to increase Fc epsilon R(+) cells. However, mixed lymphocyte cultures from two normal individuals responsed to human IgE for the induction of Fc epsilon R(+) cells. In both antigen-stimulated and mixed lymphocyte cultures, a portion of Fc epsilon R(+) cells induced in vitro were T lymphocytes. Evidence was obtained that Fc gamma R(+) cells are involved in the induction of Fc epsilon R(+) cells. Depletion of Fc gamma R(+) cells in the lymphocytes from ragweed-sensitive patients, before culture with antigen E and IgE, abolished the ability of the lymphocytes to respond to IgE for an increase in Fc epsilon R(+) cells.

DNA↗
PubMed1979

Lymphocytes bearing Fc receptors for IgE. II. Induction of Fcepsilon-receptor bearing rat lymphocytes by IgE.

The proportion of lymphocytes bearing receptors for IgE (FcepsilonR) markedly increased after infection of rats with Nippostrongylus brasiliensis (Nb). The FcepsilonR-bearing lymphocytes from the infected animals bound more IgE-coated erythrocytes in rosette assay than FcepsilonR-bearing cells from normal rats, suggesting that the number of FcepsilonR per cell may also increase following the infection. In contrast, the number of IgE-receptors on peritoneal mast cells did not change after Nb infection. The increase in the proportion of FcepsilonR-bearing lymphocytes in Nb-infected rats is probably due to an increased concentration of IgE in the environment. The proportion of FcepsilonR-bearing cells in normal rat lymphocyte suspensions increased by culture of the cells with rat IgE of 1 microgram/ml or higher concentration. Other immunoglobulins such as rat IgG, human IgE, or rabbit IgG failed to induce either FcepsilonR-bearing cells or FcgammaR-bearing cells. It was also found that induction of Fc receptors by rat IgE is confined to FcepsilonR. Kinetic studies on the induction of FcepsilonR-bearing lymphocytes in vitro showed that the proportion of these cells in lymphocyte suspensions increased within 8 hr incubation with rat IgE but not within 4 hr. Evidence was obtained that both RNA synthesis and protein synthesis, but no DNA synthesis, are required for the induction of FcepsilonR-bearing cells or the expression of the receptors on the cell surface.

Animals↗
PubMed1978

A hypotetraploid human T lymphoid cell line established by cell fusion.

A human T lymphoid cell line was established by cell hybridization technique from peripheral blood leucocytes of a patient with Sezary syndrome. The cells beared the surface antigens of human T lymphocyte specificity as demonstrated by immune cytolysis tests, but did not form E rosettes with sheep red blood cells. Isozyme patterns of enzymes in this line such as lactate dehydrogenase, glucose 6-phosphate dehydrogenase and esterase were of human type. The line had 79 chromosomes in modal number. This case supports the proposal that the production of tetraploids is favourable for establishment of cell lines.

Antigens↗