The permeability of the lymphocyte membrane: applying a particle size analyzer and a hybrid computer to measure rapid changes in cell volume.

In summary, this method is ten to twenty times more sensitive than the densimeter method as presently employed. This is not to say that densimeter methods may not be feasible if suitably modified. For example, modern flow systems such as those used at Los Alamos Scientific Laboratories, which measure light transmittance and scattering on an individual cell-by-cell basis, could probably be modified and adapted to summate individual pulses as the population responds to an osmotic gradient prior to entry into the analyzer. Nevertheless, with our present method, we are able to measure the permeability profile of lymphocyte populations from peripheral blood. It should be readily applicable to isolated populations from aspirated bone marrow.