Plasma and organ counts of 3H in normal or immune mice and sheep injected with 3H-ε-dinitrophenyl-lysine

Mice and sheep with circulating antibody to dinitro-phenol (Dnp) retained injected 3 H-e-Dnp-Iysine in their circulation for three and seven days respectively. In normal mice and sheep the 1 h post injection counts of 3 H/g of kidney were higher than those per ml of plasma. In immune mice, plasma 3 H counts were always higher than kidney counts, whereas at 1 h in immune sheep, plasma and kidney counts were similar. Liver, spleen and lung counts were also made in some experiments. Increased 3 H counts could be demonstrated in mice treated passively with sheep anti-Dnp serum and then given 3 H-e-Dnp-lysine. The fast y-globulin of sheep antiserum is mainly responsible for retention of hapten in mouse plasma.