Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
8
pubmed:dateCreated
1988-11-9
pubmed:abstractText
The depletion of an essential amino acid, tryptophan, caused by indoleamine 2,3-dioxygenase induction in vitro, has been shown to be due to a mechanism that is used in self-defense against inhaled microorganisms and tumor growth. In this communication, we report the results of measuring dioxygenase activity in the peritoneal exudate cells and tumor cytotoxicity at the transplantation loci after in vivo transplantation of tumor cells into the peritoneal cavity of syngeneic or allogeneic strains of mice. The enzyme was induced only when the tumor cells were being rejected from allogeneic animals and no change was observed when the cells continued to grow in syngeneic animals. Furthermore, when the syngeneic tumor cells in a diffusion chamber were i.p. transplanted simultaneously with i.p. injection of allogeneic tumor cells, the enzyme was induced not only in allografted tumor cells but also in the syngeneic tumor cells. Under these conditions, the tumor cells in the diffusion chamber ceased to grow and 50% of the cells were rejected. To determine the type of cells containing the induced enzyme, the peritoneal exudate cells (tumor cells and host cells--mostly small lymphocytes) were separated into six fractions by sedimentation under gravity and by differential centrifugation. Approximately 80% of total enzyme activity was localized in a tumor-rich fraction (98.9% purity), whereas only 0.2% of the activity was found in a lymphocyte-rich fraction (99.5% purity). The localization of indoleamine 2,3-dioxygenase in the tumor cells was confirmed by complement-dependent lysis with specific antibodies against tumor and host cells.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0022-1767
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
141
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2819-23
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1988
pubmed:articleTitle
Tryptophan degradation in transplanted tumor cells undergoing rejection.
pubmed:affiliation
Department of Medical Chemistry, Kyoto University Faculty of Medicine, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't