Two Populations of Murine LPS-Responsive B Lymphocytes Differing in Recirculatory Capacity

Abstract

The fate of injected syngeneic, chromosomally-distinguishable T cells can be followed by taking serial samples of blood and culturing the lymphocytes with phytohaemagglutinin (PHA). As has been described elsewhere the resultant analysis affords not only an estimate of T-cell pool size but repeated sampling can be used to give an indication of the cell flow rate through the pool (1). Attempts to apply the same methods to the study of B lymphocytes present in a 0.3 ml sample of blood was too small to give enough mitoses in LPS-stimulated cultures so mice had to be killed at each time point rather than bled serially. Further, many more cells had to be injected to obtain reasonable levels of B cell chimaerism particularly when lymph nodes were used as the source of B lymphocytes. Thus one experiment required very large numbers of mice.