New analysis of the effect of white blood cells on blood filtration

Abstract

Fractional filtration experiments were carried out to study the transit of white blood cells through 5 µm polycarbonate filters in a constant pressure system. The proportion of white blood cells filtered increases from 24% to 78% from the first to the seventh fraction filtered, while the red blood cell concentration remained unchanged. The filtration rate of blood (relative to the medium) with a constant red cell concentration but different concentrations of white blood cells was determined. The relative filtration rate versus filtered volume showed linear relationship if the concentration of white blood cells was less than 0.25 × 10⁹ /l in the non-filtered sample. At higher concentrations of white blood cells the function became non-linear making it more difficult to determine the initial relative filtration rate. A comparison of the two types of experiments provided a function between the number of trapped white blood cells and relative filtration rate of suspension indicating the importance of white blood cells in filtration experiments.