The role of avian macrophages in the production of avian lymphokines

Lymphocyte inhibitory factor (LyIF) and lymphocyte chemotactic factor (LCF) were produced by sensitized thymic (T) and bursal (B) cells and thymic (T) cells, respectively. The passage of sensitized T and B cells through a Sephadex G-10 column abrogated the ability of T cells to produce LyIF and LCF while B cells remained capable of producing LyIF. The return of macrophages to the adherent cell depleted population reconstituted the T cells' ability to produce LyIF and LCF. These data suggest a greater macrophage dependency of thymic cells than bursal cells in the production of lymphokines.