The concentration of apolipoprotein A-I in human peripheral lymph

The concentration of apolipoprotein A-I in peripheral lymph of eight apparently healthy subjects has been determined by quantitative immunoelectrophoresis. Under steady-state conditions the average concentration of this apolipoprotein in lymph was 15.9 +/- 3.6 mg/dl, that is 12.24 +/- 2.3% of its concentration in plasma of the corresponding subjects. Apolipoprotein A-I could not be detected immunochemically in particles smaller than haemoglobin (Mr 67 000) when lymph was subjected to gel filtration on Sephacryl S300 superfine either by thin-layer or column modification of this method. Lymph and plasma from three subjects were fractionated by column gel filtration and apolipoprotein A-I determined by quantitative immunoelectrophoresis in delipidated fractions. It was found that the distribution of apolipoprotein A-I in lymph was shifted towards larger particles when compared to its distribution in plasma.