Concentration of lipoproteins containing apolipoprotein B in human peripheral lymph

The concentration of apolipoprotein B (apoB) in human serum and peripheral lymph was measured by quantitative immunoelectrophoresis with anti-serum to human low-density lipoprotein. In four normal and six hyperlipidaemic subjects, total lymph apob/ml was 5-10% of total serum apoB/ml in the same subject. These ratios were equivalent to lymph apob concentrations of 60-120 microgram/ml. When the assays were carried out under conditions in which unmasking of immunoreactive sites on lymph and serum apoB was assumed to be maximal (delipidation with Nonidet P40), the lymph/serum apoB concentration ratios in three normal subjects were similar to those obtained with untreated lymph and serum.