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J Y Lin

Publications and source records attributed to J Y Lin.

At least 163 records · Page 9Linked to original sources
PubMed1985

Antitumor lectin-trypsin inhibitor conjugate.

Concanavalin A (Con A) and trypsin inhibitor isolated from Acacia confusa were covalently linked with N-succinimidyl-3-(2-pyridyldithio)propionate. Con A-A. confusa trypsin inhibitor (ACTI) conjugate covalently bound (Con A-ACTI) retained about 42% of the trypsin inhibitory activity present in the native ACTI and had a higher hemagglutinating activity than did the native Con A. Con A-ACTI had a greater resistance to tryptic digestion than did the mixture of Con A and ACTI. The conjugate entered sarcoma 180 tumor cells, whereas the free ACTI did not. A single dose of the conjugate injected ip into noninbred N:NIH(S) white mice bearing sarcoma 180 had a remarkable effect of increasing the survival of tumor-bearing mice, while the mixture of an equivalent dose of free Con A and ACTI was not effective.

Animals↗
PubMed1984

Isolation and characterization of a lectin from edible mushroom, Volvariella volvacea.

A lectin was purified from edible mushroom, Volvariella volvacea by extraction with 5% cold acetic acid in the presence of 0.1% 2-mercaptoethanol, followed by ammonium sulfate fractionation, and DEAE-C-52 and CM-C-52 column chromatographies. The molecular weight was measured to be 26,000, and the lectin consisted of two non-identical subunits as demonstrated by gel filtration and polyacrylamide gel electrophoresis. The lectin does not contain half-cystine, methionine, or histidine. The LD50 of the lectin is 17.5 mg per kg body weight of mice. The lectin has a moderate inhibitory effect on the growth of tumor cells.

Agaricales↗
PubMed1984

Identification of anti-human IgG monoclonal antibodies and monoclonal antibodies with confined subclass reactivity.

In a previous paper, 4 hybridoma cell lines (1B3, 2D5, 2A4 and 2B6) secreting antibodies against heavy chain of human IgG were reported. In this paper a more detailed study of these McAbs was introduced. First of all they were studied with double immunodiffusion test in agarose and it was demonstrated that they were reactive against 3 distinct antigenic determinants of human IgG. This result was also confirmed by ELISA competition test. These McAbs were further analysed for human IgG subclass proteins and it was found that 1B3 McAb gave positive reaction with all subclasses of IgG while the other 3 possessed confined subclass reactivity, i.e. McAb 2A4 did not react with IgG3 (called non-IgG3 McAb), and both McAbs 2D5 and 2B6 did not react with IgG4 (called non-IgG4 McAb). By agarose immunodiffusion test it was shown that: (i) Only transparent precipitation line was formed when McAb reacted with IgG antigen, however, in agarose containing 2% PEG-6000, the transparent precipitation line becomes opaque; (ii) When a mixture of two McAbs against the same antigenic determinants (2D5 and 2B6) was placed into the same well, the precipitation line remained transparent, but if they were not identical (2A4 and 2D5), then opaque precipitation line formed even in the absence of PEG. It was suggested that this phenomenon should be used for preliminary analysis for the identity among McAbs. The confined IgG subclass McAb may be used for the preparation and purification of IgG3 or IgG4 protein before specific McAb against IgG3 or IgG4 is obtained.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies, Monoclonal↗
PubMed1982

Formation of mutagens in boiled pork extract.

When boiled pork extract was heated under reflux at 102 degrees C for 4 hr mutagens, which were detected using Salmonella typhimurium strains TA98 and TA1538, were formed. The level of mutagenicity was dependent on the concentration of pork in the extract, the duration of boiling and on pH; the optimum pH for mutagen formation was found to be 9 to 11. Thin-layer chromatographic analysis showed that the mutagens formed in boiled pork extract were chromatographically distinguishable from benzo[a]pyrene and from the primary mutagenic pyrolysis products of tryptophan (3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole and of glutamic acid (2-amino-6-methyldipyrido[1,2-a:3',2'-d]imidazole).

Animals↗
PubMed1982

Inhibitory effects of four isoabrins on the growth of sarcoma 180 cells.

The four isoabrins were shown to be capable of inhibiting the growth of tumor cells in vivo when one-fifth of their median lethal dose was used. From the in vitro experiments, the doses required for 50% inhibition of protein biosynthesis are 3.2 pg, 45 ng, 32 ng, and 10 ng/ml for abrin-a, -b, -3, and -d, respectively. Except for abrin-b, a good correlation between the inhibitory effects of abrins on the tumor growth and protein biosynthesis was observed. These isoabrins show a moderate inhibitory effect on DNA biosynthesis.

Abrin↗
PubMed1982

Induction of antitumor immunity by tumor cells treated with abrin.

Abrin is known as a cytotoxic lectin. Immunization with Meth-A tumor cells which were treated in vitro with abrin induced a strong antitumor immunity in syngeneic BALB/c mice. The immunizing effect was stronger than that produced by an irradiated Meth-A tumor cell vaccine. Studies on the mechanisms of the immunizing effect with the abrin-treated tumor cells demonstrated that abrin acts as an immunoadjuvant. Furthermore, the regression of a growing Meth-A tumor was observed after abrin was injected into the tumor, while the induction of a strong antitumor immunity also occurred. It appears, therefore, that the antitumor effects of abrin are attributable to two kinds of activity: cytotoxicity and adjuvant activity.

Abrin↗
PubMed1981

Lectin derivatives of methotrexate and chlorambucil as chemotherapeutic agents.

Methotrexate and chlorambucil, each covalently linked to either abrus agglutinin, abrin, ricinus agglutinin, ricin, or concanavalin A, were prepared. A single dose of the derivative injected ip into sarcoma 180-bearing noninbred N:NIH(S) white mice resulted in prolongation of the survival time and was more effective than an equivalent dose of free drug and lectin. Drug-lectin also showed a higher inhibitory effect on the DNA biosynthesis of the tumor cell than did an equivalent dose of the free drug and lectin.

Abrin↗