Proper rheological properties of red blood cells (RBC) including flexibility and aggregability are essential for healthy blood microcirculation. Excessive RBC aggregation has been observed to be associated with many pathological conditions and is crucial in acute circulatory problems. Low-level laser radiation (LLLR) has been found to have positive effects on the rheology of human blood, however, the detailed mechanisms of blood photobiomodulation remains unclear. In this study, utilizing the single-cell technique optical tweezers (OT) and traditional light microscopy, the influence of photobiomodulation of human RBC was examined under different conditions of laser irradiation. The results revealed that high radiant exposure (over 170.5 J/cm 2 radiant fluence) caused enhanced RBC aggregation and cell shape transformation while the aggregation force between single RBC remained unchanged. LLLR with radiant fluence below 9.5 J/cm 2 by 450 nm wavelength improved the RBC deformability, weakened the strength of cell-cell interaction in the RBC disaggregation process, and showed rejuvenating effects on RBC suspended in a harsh cell environment.
|Journal||Journal of Photochemistry and Photobiology B: Biology|
|Early online date||29 Mar 2022|
|Publication status||Published - May 2022|
Bibliographical note© 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license 4.0
Funding: This work was funded by China Scholarship Council (CSC No. 201706410089, R.Z.) and the Suomen Kulttuurirahasto (grant No. 00190188, T.A.). The authors also acknowledge the contribution of Russian Science Foundation (project: 19-72-30012) and support from the Academy of Finland (project 325097). I.M. acknowledges the support from the Leverhulme Trust and the Royal Society (Ref. no.: APX111232 APEX Awards 2021). The research was carried out with the support of a grant under the Decree of the Government of the Russian Federation No. 220 of 09 April 2010 (Agreement No. 075-15-2021-615 of 04 June 2021).
- Red blood cells
- Optical tweezers
- Low-level laser radiation