The galvanotactic response of human granulocytes was investigated theoretically and experimentally. The basic results are: (i) The granulocytes move towards the anode. (ii) The directed movement has been quantified by two different polar order parameters--the McCutcheon index and the average of cos phi. (iii) The polar order parameters are a function of the applied electric field (= dose-response curve). (iv) The inverse of the galvanotactic constant of migrating cells (analogous to the Michaelis-Menten constant) has a value of -0.2 +/- 0.03 V/mm. (v) The galvanotactic response of granulocytes is a non-cooperative process with a cooperativity coefficient of 1 +/- 0.2. (vi) The galvanotactic constant is a function of pH. (vii) The protein essential for the galvanotactic response is very likely a G-protein.
The cell-cell interaction of migrating human leukocytes (granulocytes) was investigated. We have found that the attractive pair interaction of granulocytes can be switched-off at high calcium concentrations and switched-on at low calcium concentrations.
Cytokineplasts (CKP) are granule-poor cytoplasts from human polymorphonuclear leukocytes (PMN) that retain motile function, even (unlike the parent PMN) after cryopreservation. Employing time-lapse videomicroscopy, we examined the chemotactic properties of CKP after cryopreservation toward erythrocytes lysed by laser microirradiation. Paths of locomotion were plotted for six CKP in the field, and velocities were calculated at 10-sec intervals. Mean velocities of the six fragments, ranging from 9.3 to 20.8 microns/min, are of the order of fresh, intact PMN, the fastest of locomoting cells.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.