Macrophage specificity of antiserum against thymus lymphocytes

Abstract

Potent antisera against thymus lymphocytes have been shown by light and electron microscopy, to cause an increase in close cytoplasmic contacts between macrophages in monolayer tissue culture with subsequent aggregation (macrophage interlinkage reaction). This anti-macrophage activity remains present at high dilutions of antiserum, but can be markedly reduced by prior absorption with thymus lymphocytes. Evidence is presented which indicates that anti-lymphocyte antibody may also have anti-macrophage specificity and it is suggested that part of the immunosuppressive activity of anti-lymphocyte serum may be a consequence of this additional specificity.