Experimentally induced autoantibody to heat-stable alkaline phosphatase in the baboon.

Experimental evidence has been collected which signifies that autoantibody has been induced against lung heat-stable alkaline phosphatase which represented 60% of the total alkaline phosphatase of that tissue. Immunization of a male baboon with highly purified human placental alkaline phosphatase (heat-stable and cross-reactive with the baboon heat-stable enzyme) resulted in production of a precipitating factor in the immune serum which reacted with the heat-stable enzyme of both the human and baboon but not the heat-labile form of alkaline phosphatase of either species. This precipitating factor is a baboon autoantibody because 1) it had a gamma mobility on immunoelectrophoresis and retarded the electrophoretic mobility of the heat-stable enzyme from both normal and immunized baboons; 2) its titer increased as more booster injections were administered; 3) it formed a well-defined precipitin rocket with the baboon heat-stable enzyme in the Lurell's antigen-antibody crossed electrophoresis; 4) in immunodiffusion it formed a discrete precipitin line with the baboon heat-stable enzyme, which fused partially with the precipitin line of human placental alkaline phosphatase (immunogen).