The alpha-lipoprotein (a-Lp) electrophoretic pattern on agarose gel was studied serially in 65 children with acute viral hepatitis. In seven cases the high-density lipoprotein fractions (HDL) were also separated by ultracentrifugation and studied in relation to lecithin: cholesterol acyltransferase activity (LCAT) during the acute phase and recovery. The a-Lp band was initially absent on electrophoresis in 36 cases and never appeared in 3 of the children who died. In those who survived a-Lp reappeared with clinical improvement even before a definite increase in S-ASAT and bilirubin was evident. In the seven children in whom it was measured LCAT activity ranged during the acute phase from 17.4 to 57 nmol h-1 ml-1. In patients with initially 'normal' LCAT activity (group I, no. = 3) HDL was normal both in amount and composition. In patients with 'low' LCAT (group II, no. = 4) HDL was reduced and of abnormal composition. In both groups the a-Lp band was absent or considerably reduced on electrophoresis. In the latter group LCAT activity increased significantly on recovery, as did the amount of HDL which became normal in composition. These results suggest that in acute viral hepatitis in children changes in composition and concentration of HDL depend on the degree of hepatic functional disturbance, as judged by plasma LCAT activity. Nevertheless, it appears that HDL electrophoretic behaviour may be abnormal during the early stage of the disease while plasma LCAT activity is not significantly affected.

SUMMARY In a study of the lipoprotein pattern in multiple myelomatosis electrophoresis on agarose gel showed abnormal lipoproteins, named paralipoproteins (p-Lp), in 24 out of 30 normolipidaemic patients. These paralipoproteins were grouped according to their mobility into one or another of the following types: (1) p-Lp1 with a mobility identical with that of y-globulin, (2) p-Lp2 with a mobility between that of /-and y-globulin, (3) p-Lp3 with a mobility identical with that of /-globulin. On ultracentrifugation the abnormal lipoproteins were found to have a density above 1-063 g/ml.

The in vitro effect of acetylsalicylic acid, phenylbutazone and indomethacin on the electrophoretic pattern of the red cell membrane proteins is described by using the vertical urea starch-gel electrophoresis. Normally 8 bands are visible. Acetylsalicylic acid and phenylbutazone bring about the disappearance of 5 bands and indomethacin that of 6 bands.