Correlation between the growth-inhibitory effect of TGF-beta 1 and phenotypic characteristics in a panel of B-cell lines.
Human B-cell lines established from Burkitt lymphoma (BL) and normal B cells immortalized in vitro by EBV (LCLs) differ in phenotype. While the BL correspond to resting B cells, the LCLs resemble activated B cells. When BLs which have the EBV genome are carried in vitro, they acquire some of the features of LCLs, such as expression of B-cell activation markers and the tendency to form aggregates. Comparison of several B-cell lines for sensitivity to TGF-beta showed that the growth of BLs (with few exceptions), but not of the LCLs, was inhibited. The results suggested that the sensitivity to TGF-beta correlates with the cellular phenotype. In the present work, this assumption is even more critically substantiated by studying 2 sublines of an EBV-genome carrying BL line, Mutu, which were selected for single cells and aggregates. The former (with resting phenotype) was inhibited, while the subline of aggregated cells, which also expressed B-cell activation markers, was not inhibited. Somatic-cell hybrids between BLs, LCLs and non-B cells provided lines with phenotypic differences. Results with a panel of such hybrid lines also showed that those which express the activated B-cell phenotype are not inhibited by TGF-beta. Differences in the levels of expression of activation markers did not influence the response to TGF-beta.
Department of Tumor Biology, Karolinska Institute, Stockholm, Sweden.
A
A
Altiok
B
B
Ehlin-Henriksson
E
E
Klein
D001402:B-Lymphocytes / Q000166:cytology / Q000187:drug effects*; D002051:Burkitt Lymphoma / Q000473:pathology; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D002461:Cell Line, Transformed; D004854:Herpesvirus 4, Human; D006801:Humans; D006822:Hybrid Cells; D016130:Immunophenotyping; D008213:Lymphocyte Activation / Q000502:physiology; D016212:Transforming Growth Factor beta / Q000494:pharmacology*
D016212:Transforming Growth Factor beta