The Production of a Monocyte Chemotactic Factor by Agammaglobulinemic Chicken Spleen Cells

Abstract
The classification of lymphocytes into bursal derived (B) 2 and thymic derived (T) subpopulations has been a significant advance in our understanding of lymphocyte biology. A variety of immune functions have been attributed to each of these subpopulations, while other functions depend on a cooperation between both cell types (1). It has been suggested that lymphokines, the biologically active substances produced in vitro by activated lymphocytes (2, 3) are produced by T lymphocytes (2). However, little definitive experimental evidence to substantiate this conclusion has been reported. The agammaglobulinemic (aγ) chicken has been shown to be largely depleted of B cells (4, 5) and represents an excellent model in which to investigate the contributions of B and T cells to various aspects of the immune response (6). In the present investigation we have adapted a recently described assay of mononuclear leukocyte (MNL) chemotaxis (7) to study lymphokine production by mitogen-stimulated normal and aγ chicken spleen cells.