A developmentally significant antigen in the surface of frog embryo cells

Data demonstrating the role of yolk pseudoglobulin in maintaining the integrity of frog neurula cells in hanging drop cultures were recalled. Evidence was presented to demonstrate that the cytolysis of these cultured cells by antineurula sera was preceded by in situ lysis of yolk platelets. It was shown that washed yolk platelets directly exposed to the cytolytic antisera as well as to other antisera were not lysed. This led to the conclusion that the cytolysis of the cultured cells must be attributed to the action of the antisera on cell membrane antigens with pseudoglobulin specificity rather than to the passage of antibody into the cells.