Enhancer mediated suppression of epsilon heavy-chain gene expression in a murine IgE-producing hybridoma
1991; Elsevier BV; Volume: 28; Issue: 6 Linguagem: Inglês
10.1016/0161-5890(91)90128-7
ISSN1872-9142
AutoresKeats Nelms, Brian G. Van Ness, Richard G. Lynch, Ambika Mathur,
Tópico(s)Monoclonal and Polyclonal Antibodies Research
ResumoIn vitro co-culture of IgE-secreting hybridoma cells (B53) with spleen cells harvested from mice with established B53 tumours results in a specific, T cell-dependent suppression of ϵ-chain expression in the B53 cells. The role of immunoglobulin enhancers in the suppression of IgE synthesis in B53 cells was examined by transfecting B53 cells with CAT expression vectors containing the immunoglobulin heavy or kappa light-chain intron enhancers or a Rous sarcoma virus (RSV) LTR. When ϵ-chain expression of transfected cells was suppressed in vitro, CAT expression was also suppressed in cells transfected with vectors containing the immunoglobulin heavy-chain gene enhancer, but not in cells transfected with vectors containing the kappa enhancer or RSV LTR. Thus, the T cell-dependent suppression of IgE synthesis in B53 cells correlates with a specific inactivation of the immunoglobulin heavy chain enhancer, strongly suggesting that T cell-mediated suppression of Ig synthesis can normally occur through specific repression of Ig enhancer function. This represents a new regulatory pathway involved in the control of IgE synthesis and is the first indication that the enhancer mediated expression of Ig genes in B cells can be modulated through T cell-dependent processes.
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