2022 Volume 17 Issue 3 Pages 22-00083
Neutrophil motion toward inflamed regions by cytokine concentration gradient is one of the most important problems in immune function. When the velocity of neutrophil motion is high, it is considered that the immune function of neutrophils is also high. In addition, shock waves have been required to be applied more widely to medical fields. To find out the possibility of the enhancement of the immune function by working shock waves, the effects of shock waves on neutrophil propulsion (translational velocity) are investigated by changing the pressure ratio and the shot numbers of shock waves. In the experiments, the neutrophil’s motion is observed under a microscope after working plane shock waves. The translational velocity, rotational speed, and cytokine concentration gradient on the membrane are measured. From the equation of the Marangoni effect, the sensitivity of the neutrophil membrane is explained by the ratio of the translational velocity to the concentration gradient. We call this ratio the “membrane function coefficient (MFC)”. From the measurements, it was found that there is a maximum translational velocity, rotational speed, and MFC with a pressure ratio 2.5 in the range of 2.5 to 3.5. It was also found that the translational velocity, rotational speed, and MFC are decreased by increasing shot numbers by more than 1. In conclusion, it is considered that the immune function of neutrophils can be enhanced by shock waves with an optimized pressure ratio and proper shot numbers.