Antigenic studies on the psittacosis-lymphogranuloma venereum group of viruses. IV. Studies on cutaneous hypersensitivity in chickens infected with ornithosis virus.

Summary The time of onset of cutaneous hypersensitivity in chickens infected with ornithosis virus was related to the LD 50 used for infection. Hypersensitivity developed within 4 weeks of infection and was detected for 1 year after infection. Complement-fixation inhibition antibody appeared earlier in the infection than detectable allergy, although after 7 weeks of infection the serological and skin-test methods agreed in approximately 80% of the infected chickens. The skin-test antigen was resistant to periodate, trypsin, desoxyribonuclease, and exposure to 90°C. The complement-fixing and allergenic activities were separated by ultracentrifugal sedimentation of the complement-fixing antigen. The skin-test antigen was standardized on a nitrogen basis in guinea pigs and chickens.