Immune Response against Hamster Erythrocytes in the Low-Responder Mouse Strains

IX. Phagocytic Activity of Peritoneal Macrophages of the High- and Low-Responder Mouse Strains

Abstract

The present authors reported strain differences among various mouse strains in antibody production against hamster erythrocytes (HRBC) in a previous paper (SL_??_CFl>DDD>C3H/He_??_AKR>C57-BL/6). This study was undertaken to determine whether or not a strain difference existed in the ability of mouse macrophages to take up HRBC. Macrophages of the high-responder DDD, intermediate-responder AKR and low-responder C57BL/6 mice were tested. 1) Normal macrophages from these three strains exhibited similar degrees of attachment and ingestion in the presence of normal AKR serum in the medium. 2) Normal sera from DDD and C57BL/6 mice conferred the same degree of opsonizing activity on normal AKR macrophages in in vitro experiments. 3) When HRBC were injected into the peritoneal cavities of normal DDD and C57BL/6 mice, almost the same degrees of attachment and ingestion were detected in their macrophages. 4) When the antibodies to HRBC were present in in vivo or in vitro experiments, macrophages of DDD and C57BL/6 mice actively took up HRBC to similar degrees. These results led us to conclude that macrophages of the high- and low-responder mice took up HRBC to the same degrees after primary immunization.