Chemotropism of Leucocytes in Relation to Their Rate of Locomotion.

Abstract

A method was dgscribedlr for measuring the chemotropic reaction of polymorphonuclear leucocytes in v i t r o . Leucocytes were observed with the microscope and their paths recorded as they approached bacteria or other sources of attraction. In measuring the reaction to these attracting bodies only the direction of the path was taken into account, not the rate of locomotion. It seemed possible, however, that leucocytes might respond to such attraction not only by moving toward its source but by traveling at increased speed. In this case it would be desirable to take account both of direction and of velocity of approach in measuring the chemotropic reaction.The point at issue has been touched on by previous observer^,^^ 41 who, however, did not make actual measurement to compare the rate of locomotion of leucocytes approaching a source of attraction with that of leucocytes moving at random. We have made such a comparison by means of a simple method which has been described by one of US.^ A minute clump of bacteria or of other particles is placed on a glass slide, where, after drying, it appears as a flat oval or circular body from 50 to 150 microns in diameter. A drop of blood, obtained by puncturing the finger, is placed on a coverslip, lowered *This investigation was aided by a grant from the Committee on Therapeutic

Chemotaxis in Vitro

“…It is interesting to note that the "x" component mean velocity of approximately 15 pm/min does not increase in chemotaxis. This result is in agreement with reports that the actual velocity of cells does not increase in chemotaxis (15,16).…”

Electric field-directed fibroblast locomotion involves cell surface molecular reorganization and is calcium independent.

“…Cell movement with time was measured by randomly selecting thirty to forty ceils and recording the X-Y coordinates of each cell nucleus at the start and finish of each time lapse image sequence. Directional displacement was analyzed using the ~Dixon-McCutcheon ~ index method as described previously (Dixon and McCutcheon, 1936;Cooper and Schliwa, 1986). Cellular displacement along the axis of the applied field (X coordinate) was divided by the total displacement to yield the directional migration index (DMI).…”

Distinct locomotive patterns of granulocytes, monocytes and lymphocytes in a stable concentration gradient of chemokines

“…These patterns of movements can be compared using an index (DI) that can represent the directional characteristic of the movement. In fact, this kind of index has been reported 70 years ago (Dixon & McCutcheon, 1936). In terms of DI, the patterns of movements were significantly different between granulocytes and lymphocytes in response to the same chemokine, CXCL12 ( P = 0.003, n = 100).…”