Evidence that macrophages in the marginal zone have no role in the migration of lymphocytes into the periarteriolar lymphocyte sheaths (PALS).

The macrophages in the marginal zones in the spleens of mice were eliminated by the intravenous injection of dichloromethylene diphosphonate encapsulated in liposomes. When syngeneic splenic lymphocytes were labelled with [3H]uridine and injected intravenously into the treated mice, their migration from the marginal zones into the periarteriolar lymphoid sheaths did not differ significantly from than seen in untreated animals. We concluded that the migration of lymphocytes from the marginal zones of the spleen is not mediated by the local macrophages.