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Y M Kong

Publications and source records attributed to Y M Kong.

8 recordsLinked to original sources
PubMed1977

Studies on interference with tolerance induction in T cells.

The mechanism of T-cell tolerance to a thymus-dependent antigen was examined, using the adjuvant polyadenylic-polyuridylic acid (poly A:U). In adoptive transfer experiments, thymus cells obtained from donor mice 2 days after treatment with a tolerogenic dose of bovine gamma-globulin (sBGG) did not cooperate with bone marrow (BM) cells in irradiated recipients challenged with aggregated BGG (aBGG). In contrast, thymus cells from donors given sBGG plus poly A:U retained their helper activity, as assayed by hemagglutination and rosette formation of spleen cells. The effect of poly A:U in preventing tolerance induction was also demonstrable in the cortisone-resistant population, in that thymus cells from cortisone-treated donors that had received sBGG and poly A:U retained their helper function. The presence of suppressor cells and the effect of poly A:U on their stimulation were also examined. sBGG-treated thymus cells suppressed the response of BGG-primed spleen cells in lethally irradiated mice, whereas thymus cells from donors treated with sBGG and poly A:U were not suppressive. These observations show that poly A:U prevents tolerance induction and the development of suppressor activity in T cells.

Animals↗
PubMed1977

In vitro tolerance induction to a thymus-dependent antigen with BALB/c and C57BL/6 lymph node cells: effect of tolerogen concentration and duration of exposure.

Further studies on tolerance induction in vitro to bovine gamma globulin (BGG) in nonadherent BALB/c lymph node cells showed that it was dependent upon both the dose of tolerogen and the time of exposure. Nearly complete tolerance was achieved at a dose of 1.0 mg/ml and an incubation time of 12-18 hours. When C57BL/6 strain was used for comparison with the BALB/c strain because of its relative ease to become tolerant after in vivo injection of tolerogen, the rate of tolerance induction of its nonadherent lymph node cells was not different from that of BALB/c cells. Thus, in the absence of other host factors, the acquisition of tolerance by lymphocytes is gradual and may reflect the time required for a cell to reach a susceptible phase of the cell cycle and/or the activation of suppressor cells.

Animals↗
PubMed1975

Multiple antigenic sites on an eicosapeptide. I. Precipitin studies in the goat.

Purified peptide 105-124, an antigenic determinant from the carboxy terminus ribonuclease, was found to form an immune precipitate with antibody to that region prepared by affinity chromatography from goat hyperimmune antiserum to reduced carboxymethylated ribonuclease (CM-RNase). Cm-rnase also gave an immune precipitate with the antibody. Purified antibody to another region of similar size (40-61) did not form a precipitate with CM-RNase but did co-precipitate in the presence of antibody to peptide 105-124 and CM-RNase. The precipitin reaction between antibody to peptide 105-124 and CM-RNase was inhibited by two synthetic derivatives, peptides 118-124 and ala114-RNase 114-124. Stoichiometry of the precipitin reactions of antibody to 105-124 with CM-RNase or peptide 105-124 suggested an antigen valency of three or more. Consistent with this both peptides 105-124 and ala114-RNase 114-124 elicited immediate cutaneous reactions but 118-124 did not. These findings suggest that the eicosapeptide 105-124 is multivalent since at least three antibodies can react simultaneously with it.

Animals↗