Maturation signals for human B cells. Use of the MTT assay and EBV-transformed cell lines to define signals which promote cell growth or immunoglobulin secretion.
There are now several relatively well-defined signals that promote B-cell growth and maturation, usually termed 'growth' and 'differentiation' factors (e.g., IL-1, IL-2, BCGF, BSF-1 (IL-4) and BSF-2). In addition, much work has been carried out using continuous cell lines to examine the effects of these two classes of material. Using two different assays to enumerate cell growth and the ELISA to quantify Ig secretion, we would like to emphasize the importance of determining the final cell number when investigating so-called 'differentiation factors', particularly when continuous cell lines are the targets. The results presented here show that materials which promote DNA synthesis in B-cell lines (e.g., IL-1, BCGF) will also cause an increase in Ig secreted, suggesting that they can also promote Ig synthesis. However, when we used the MTT assay to quantitate cell numbers at the end of the assay and then calculated the Ig secreted per cell, only BSF-2 caused an increase in Ig secreted per cell. These results illustrate the importance of determining the final cell number when using continuous cell lines to investigate the actions of materials which modulate human B cell function and suggest that the MTT assay is a simple way of doing this.
D000921:Antibody-Producing Cells / Q000166:cytology / Q000502:physiology*; D001402:B-Lymphocytes / Q000166:cytology*; D002454:Cell Differentiation; D002455:Cell Division; D004247:DNA / Q000096:biosynthesis; D006801:Humans; D008222:Lymphokines / Q000502:physiology*; D008928:Mitochondria / Q000201:enzymology; D013936:Thymidine / Q000378:metabolism
D008222:Lymphokines; D004247:DNA; D013936:Thymidine