T cell-derived lymphokines, known as B cell differentiation factors (BCDF), play a critical role in the regulation of B cell differentiation. These BCDFs are present in the supernatants (SN) of a long-term alloreactive T cell line, PK 7.1. In this report we present evidence that B cells cultured with lipopoly-saccharide (LPS) and BCDFs express increased levels of both the secreted and membrane forms of γ1 mRNA. The appearance of mRNA for the membrane form of μ precedes the appearance of μ secreted form mRNA. Approximately 1 day later, appearance of membrane and secreted forms of γ3 and γ1 can be detected with the membrane forms of both isotypes peaking earlier than the corresponding secreted forms. The mRNAs for both the membrane and secreted forms of γ3 are suppressed in the presence of LPS and PK 7.1 SN while LPS alone induces an increase in both. Quantification of newly synthesized nuclear and cytoplasmic RNA for μ, γ3, and γ1 RNA suggests that PK 7.1 SN down-regulates levels of γ3 RNA by decreasing its transcription. In contrast, it may increase level of γ1 RNA by effects exerted at the post-transcriptional level. Taken together, these results demonstrate that T cell-derived lymphokines can act on B cells by regulating the levels of nuclear and cytoplasmic RNA specific for γ1 and γ3.
|Original language||English (US)|
|Number of pages||11|
|Journal||Journal of Molecular and Cellular Immunology|
|State||Published - Dec 1 1985|
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