Down regulation of Qa gene expression on drug-modified tumor cells.

Abstract

BACKGROUND:

Mouse leukemia, L1210, strongly enhances its immunogenicity following in vivo treatment with 5-(3-3'-dimethyl-1-triazeno) imidazole-4-carboxamide (DTIC). Previous experiments have shown that transformed cells elicit a cell-mediated response accountable for rejection and resistance to a subsequent injection of parental tumor into a syngeneic host. L1210 expresses classical H-2 class I molecules, and since it has been shown that DTIC treatment does not modify the expression of these molecules, this is a suitable model to study nonclassical class I antigens, such as Qa2 glycoproteins, and their potential role in tumorigenicity.

METHODS:

Cloned cells from L1210 were treated with DTIC and then H-2D, and Qa antigen expression was studied on four clones, before and after xenogenization with DTIC.

RESULTS AND CONCLUSIONS:

a strong decrease of Qa2 molecule expression was demonstrated by radioimmunoassay and immunofluorescent staining and was confirmed by FACS and 2D-gel analysis. The presence or the absence of Qa antigens on tumor cells could thus be involved in tolerance or rejection of tumor cells in syngeneic animals.

• Authors: E Leroy, D Lattuada, C Casnici, P Franco, O E Marelli
• Journal: Tumori (Tumori) Vol. 79 Issue 6 Pg. 439-43 (Dec 31 1993) ISSN: 0300-8916 [Print] United States
• PMID: 8171747 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Dacarbazine

Topics

• Animals
• Dacarbazine (pharmacology)
• Down-Regulation
• Female
• Fluorescent Antibody Technique
• Gene Expression Regulation, Leukemic (drug effects)
• Genes, MHC Class I (drug effects)
• Leukemia L1210 (genetics, immunology)
• Male
• Mice
• Mice, Inbred BALB C
• Mice, Inbred DBA
• Tumor Cells, Cultured