Abstract
Collagenase digestion of lung fibroblast antigen preparations was shown to destroy their antigenic reactivity in most instances when reacted with lung-reactive antibodies. In other instances, elastase digestion rendered the preparation nonreactive. Such a finding demonstrates that collagen and/or elastin are the major components involved in this reactivity. This was also supported by sensitizing the fibroblast with rabbit antihuman lung coUagen and demonstrating an inhibition when these same fibroblasts were used in the antiglobulin consum,ption test with known lungoe reactive sera. The use of fibroblast cells as antigens in other serological tests was also, studied. Cytotoxicity tests showed definite cytopathic effect when conducted with lung-reactive sera. Similar cytopathic changes were not noted with sera from either chronic disease patients or the control sera.