T lymphocytes and neutrophil granulocytes differ in regulatory signaling and migratory dynamics with regard to spontaneous locomotion and chemotaxis

Chemotactic migration of T lymphocytes and neutrophil granulocytes within a three-dimensional collagen matrix is distinct from spontaneous, matrix-ind uced migration concerning dynamic parameters and regulatory intracellular s ignaling. Both spontaneous T lymphocyte locomotion and stromal-cell-derived factor-1 (SDF-1)-induced chemotaxis-involved protein tyrosine kinase (PTK) activity, whereas only SDF-1-induced migration was protein kinase C (PKC) dependent. Spontaneous locomotion of neutrophil granulocytes was independen t of PKC and PTK activity, but formyl-methionyl-leucyl-phenylalanine-induce d migration involved PKC activity. In addition, the microtubule cytoskeleto n was not changed after induction of chemotaxis in both cell types. T lymph ocytes had a well-developed microtubule cytoskeleton with the microtubule o rganizing center located in the uropod, whereas neutrophil granulocytes rev ealed a clustered tubulin distribution at the leading edge of the migrating cell. Therefore, differences of the microtubule cytoskeleton might contrib ute to differences in locomotion between T lymphocytes and neutrophil granu locytes but not to differences between spontaneous locomotion and chemotaxi s, (C) 2000 Academic Press.