Effect of mechanical deformation on structure and function of polymorphonuclear leukocytes

Yuko Kitagawa, Stephan F. Van Eeden, Darlene M. Redenbach, Maleki Daya, Blair A. M. Walker, Maria E. Klut, Barry R. Wiggs, and James C. Hogg University of British Columbia Pulmonary Research Laboratory, St. Paul's Hospital, Vancouver, British Columbia, Canada V6Z 1Y6 Received 30 September 1996; accepted in final form 22 January 1997. Kitagawa, Yuko, Stephan F. Van Eeden, Darlene M. Redenbach, Maleki Daya, Blair A. M. Walker, Maria E. Klut, Barry R. Wiggs, and James C. Hogg. Effect of mechanical deformation on structure and function of polymorphonuclear leukocytes. J. Appl. Physiol. 82(5): 1397-1405, 1997. The present studies were designed to test the hypothesis that mechanical deformation of polymorphonuclear leukocytes (PMN) leads to functional changes that might influence their transit in the pulmonary capillaries. Human leukocytes were passed through 5- or 3-µm-pore polycarbonate filters under controlled conditions. Morphometric analysis showed that the majority of PMN were deformed and that this deformation persisted longer after filtration through 3-µm filters than through 5-µm filters ( P < 0.05) but did not result in the cytoskeletal polarization characteristic of migrating cells. Flow cytometric studies of the filtered PMN showed that there was a transient increase in the cytosolic free Ca 2+ concentration after both 3- and 5-µm filtration ( P