The effect of sheep anti-L and certain cattle S-system reagents on active potassium transport in sheep and cattle red blood cells

Certain anti-sheep L antisera stimulated active potassium transport in cattle red cells. All cattle red cells tested (red cells from 21 Jersey cows) which had an internal K level of less than 70 mmol/1 were stimulated but those with more than 75 mmol/1 of K (red cells from 7 Jersey cows) were not stimulated. Cattle S-system reagents and isoimmune cattle sera produced by injecting red cells of low-potassium type into cows with cells of high-potassium type failed to stimulate active potassium transport in either cattle or sheep red cells.