Migration of mouse lymphocytes in vitro. I. Normal lymph node lymphocytes.

Normal unstimulated mouse lymph node lymphocytes (LNLs) migrated into filters in a gradient of normal mouse serum (NMS), heat-inactivated mouse serum (HI-MS), or zymosan-activated mouse serum (ZAS). Blind well chemotaxis chambers with 5-micrometer pore size cellulose nitrate membranes were used. Migration was assessed both by the leading front technique and the mean aggregate number. A concentration of 2.5 x 10(6) LNLs/ml or greater was needed to detect migration. Migration of LNLs to 1% NMS was time dependent and was inhibited by cytochalasin B. Comparison of the migration patterns of LNLs, neutrophils, and macrophages revealed that all cell types were responsive to NMS. LNLs responded as well to HI-MS as they did to NMS, neutrophils responded less well to HI-MS than to MMS, and macrophages did not respond to HI-MS. The LNL response to ZAS was significantly greater than the response to NMS to HI-MS and neutrophils and macrophages also responded strongly to ZAS. The migration of LNLs from various mouse strains to NMS revealed that the LNLs from different mouse strains possess varying degree of motility. The factor in mouse serum which induced migration was not strain specific. The LNLs from peripheral (inguinal, axillary, and brachial) nodes demonstrated greater motility in response to NMS than mesenteric LNLs. Using the checkerboard assay to discriminate chemotaxis from chemokinesis, mouse serum appeared to be solely chemokinetic when the leading front technique was used. However, using the mean aggregate number technique, mouse serum was determined to be both chemokinetic acid chemotactic for LNLs. The results indicate that the method can be reliably used to study those factors which influence the motility of normal or altered populations of lymphocytes.