Abstract
The study of continuous lines of murine cells with macrophage-like properties may provide important information concerning biochemical parameters associated with particular types of macrophage functions. Chemotaxis, phagocytosis, adherence, and antibody-dependent cellular cytotoxicity (ADCC), as well as the activities of several intracellular enzymes, were measured in two such cell lines, P388D1 and J774.1. These measurements were compared to those of “resting” and “stimulated” murine peritoneal macrophages. The data show that the P388D1 and J774.1 cell lines, although displaying many biologic characteristics of normal stimulated or resting macrophages, differ quantitatively from each other and from the normal or stimulated cells. Interestingly enough, the P388D1 cells, although the most cytotoxic in ADCC, displayed virtually no chemotactic responsiveness in vitro. Although the J774.1 cells responded as effectively to the chemotactic stimulus C5a as did the resting peritoneal macrophages, they did not migrate toward lymphocyte-derived chemotactic factor (LDCF). Both cell lines contained levels of acid phosphatase comparable to stimulated peritoneal macrophages; however, the P388D1 cells were markedly deficient in adenosine deaminase when compared to the peritoneal macrophages or to the J774.1 cells.
These studies demonstrate the heterogeneity of biologic activities displayed by various macrophage preparations and illustrate the potential usefulness of continuous cell lines in determining biochemical parameters associated with specific macrophage functions.