ABSTRACT

This chapter points out some of the unexplored areas in the macrophage-research field. It first deals with the phagocytosis and "processing" of antigen by macrophages. Subsequently, the evidence which suggests that macrophages are indeed involved in many immunological reactions, both humoral and cell-mediated, is presented. Macrophage-independence of antigens may be related to the size or molecular dimension of the antigen. It also happens that polymerized polymerized flagellin (POL) is a thymus-independent antigen whereas sheep red blood cells (SRBC) is thymus-dependent. The chapter considers the evidence for the role of macrophages in the induction of the immune response to hapten-carrier conjugates. The available data suggest that macrophages bearing antigen in some form interact with "T" cells prior to involvement of bone marrow precursors of antibody-producing cells. Macrophages as well as lymphocytes appear to have the capacity to destroy foreign tumor cells.