Uptake and degradation of a polypeptide antigen by stimulated and unstimulated macrophages from responder and non responder mice

An increase in the level of acid phosphatase, β glucuronidase and cathepsin D in macrophages was obtained by cultivating the cells in medium containing high serum concentration and by injecting macrophage donors with thioglycollate. A high level of the 3 hydrolytic enzymes in the stimulated macrophages does not correlate with a high uptake or degradation of the polypeptide antigen (TG) PRO--L. Moreover, macrophages with a low level of enzymes (unstimulated cells) pinocytose and degrade (TG) PRO--L more efficiently than macrophages with a high content of hydrolases. Unstimulated macrophages from responder (SJL) mice pinocytose and degrade (TG) PRO--L more efficiently than macrophages from the nonresponder (DBA/1) animals although the two cell populations had similar levels of hydrolases.