Binding of a rhodamine-labeled lipopolysaccharide to lipopolysaccharide-responder and nonresponder lymphocytes.

The binding levels of a highly soluble rhodamine-labeled lipopolysaccharide (LPS-Rh) on different LPS-responsive and nonresponsive murine spleen cells were measured with a cytofluorometer (CFM). In all the experiments, a preferential binding of LPS-Rh to LPS-responsive cells was observed. Furthermore, only a proportion of B cells from the responder mouse strain was selectively stained after addition of LPS-Rh. These findings suggested that LPS-Rh binds to specific components of the cell membrane, involved in the triggering of B-cell mitogenicity.