Molecules, Cells, and Parasites in Immunology contains the proceedings of a symposium on immunology held in Mexico City in the fall of 1979 under the auspices of the National University of Mexico (UNAM). This volume brings together prominent foreign scientists and Mexican investigators to discuss the areas of immunology that being developed at UNAM. Either in the form of reviews or of original presentations, the various authors proffer observations and ideas that generally relate to the regulation of the immune response at the molecular and cellular levels. The topic of Molecules encompasses the effect of molecular aggregation upon the triggering of physiological events, cooperative binding, and the expression of immunoglobulins during the lymphocyte differentiation process. Under the heading of Cells, there are contributions dealing with the physiological and pathological roles of interiorized antibodies; the mechanisms of antigen recognition by T cells; and the synthesis of membrane proteins by myeloma cells which somehow protect them from killer T cells. The section on Parasites includes some unique contributions on the immunology of human and animal cysticercosis and amebiasis, complemented by a general discussion of host-parasite relationships.