Sanford S. Elberg

Macrophage membranes viewed through a scanning electron microscope.

When rabbit peritoneal macrophages were cultured in serum and Tyrode medium, numerous membranous structures varying in size and transparency were observed to cover the surface in complex cascading patterns. Modifications in the methods of fixation and drying probably accounted for the new perspective of macrophage surfaces gained in this study.

Action of Glycine and a Lysozyme-like Agent from Rabbit Monocytes in Destruction of Brucella.∗

Summary A lysozyme-like material from rabbit monocytes is described. It acts on glycine-treated brucella to cause lysis and death. When parasitized monocytes containing this agent are treated with low concentrations of glycine, intracellular growth and yields of smooth Brucella melitensis, Rev Is is suppressed. The theory is proposed that intraphagocytic death involves a stepwise alteration of the wall, followed by enzymatic degradation of the mucopolysaccharide component responsible for structural integrity of the bacteria.

Response of Peritoneal Exudate Cells to Brucella melitensis. Influence of Nature of Inflammatory Irritant.

Conclusion Studies on mononuclear cell responses to B. melitensis require that attention be paid especially to the nature of inflammatory agent itself when interpreting behavior of the mononuclear cell. The inflammatory substance may so alter mononuclear response as to reverse cytolytic susceptibility of monocytes from normal and immunized animals.

Response of Normal and Immune Histiocytes of Various Animal Species to Infection by Brucella melitensis

Summary Inflammatory-induced peritoneal histiocytes of rabbit, guinea pig and monkey, both normal and immunized, respond to the cytotoxic action of parasitizing brucella within 24 hours. Normal cells undergo about 30% loss whereas immune cells resist completely the cytotoxic action for at least 96 hours and retard intracellular multiplication for at least 144 hours. Cells of rabbits, guinea pigs, and monkeys react alike in these respects. The cellular immunity produced by the Rev I strain of B. melitensis was also operative against virulent B. suis.

Autoradiographic studies on intracellular growth of Brucella melitensis and thymineless E. coli.

Summary Rabbit peritoneal histiocytes labelled with tritiated thymidine were infected with Brucella. No transfer of the labelled nuclear material from the host to the parasite was detected, although both types of cells multiplied during the course of the experiment. When unlabelled histiocytes ingested labelled E. coli, living or dead, label passed to the histiocyte nucleus. Uptake of tritium-labelled thymidine by peritoneal histiocytes was markedly reduced after ingestion of E. coli but not by ingestion of the attenuated strain of B. melitensis.

Observations on Cytotoxic Effect of Antihistiocyte Serum.

Summary Preliminary observations of the cytotoxic action of guinea pig antirabbit histiocyte serum mediated by large amounts of guinea pig complement have been presented. The data suggest that guinea pig complement does not act in the same manner in this system as it does in the sheep-red cell system with respect to the amount required and to its action at 0°C.

Enhancement of Bacterial Infection by Homologous Gastric Mucin.

Summary Homologous mucin will induce the phenomenon known as enhancement of infection in mice as well as the more routinely used hog gastric mucin.