Distribution of the A blood group activity on lipid and nonlipid fractions of pig organs.

Lipids and protein-containing nonlipids of pig erythrocytes, serum and several organs were tested for A blood group activity. Both lipids and nonlipids of brain, myocardium, skeletal muscle and adipose tissue show no A activity. The way of distribution of A activity on lipids and nonlipids of other tissues and serum differs among individual pigs. With respect to the acquisition of A activity of erythrocytes in a postnatal period, it seems likely that the lipidic A substance Tor part of it containing the A determinant) is transferred from plasma to the erythrocyte membrane.