Effects of the phenotypic polarization state of human leukocytes on the optical absorbance spectrum

Author(s)

de Brito Sousa, Kaline ^[1] ; de Fatima Teixeira da Silva, Daniela ^[1] ; Rodrigues, Maria Fernanda Setubal Destro ^[1] ; Garcia, Monica Pereira ^[1] ; de Oliveira Rodini, Carolina ^[1] ; Mesquita-Ferrari, Raquel Agnelli ^{[1, 2]} ; Hamblin, Michael R. ^[3] ; Bussadori, Sandra Kalil ^{[1, 2]} ; Nunes, Fabio Daumas ^[4] ; Fernandes, Kristianne Porta Santos ^[1]

Affiliation

^[1] Nove Julho Univ UNINOVE, Postgrad Program Biophoton Appl Hlth Sci, R Vergueiro 235-249, BR-01504001 Sao Paulo - Brazil

^[2] Nove Julho Univ UNINOVE, Postgrad Program Rehabil Sci, Sao Paulo - Brazil

^[3] Univ Johannesburg, Laser Res Ctr, Fac Hlth Sci, Johannesburg - South Africa

^[4] Univ Sao Paulo, Sch Dent, Dept Oral Pathol, Sao Paulo - Brazil

• Document type: Journal article
• Source: Journal of Biophotonics; v. 14, n. 6 MAR 2021.
• Web of Science Citations: 0

Abstract

This study evaluated the optical absorbance spectrum of human monocytes, neutrophils and lymphocytes polarized, or not, to the inflammatory or immunoregulatory phenotypes. Peripheral human blood leukocytes were isolated and polarized (10 ng/mL) with LPS or IL-4 + LPS for 2 hours. After polarization, cells were washed and incubated for an additional 24 hours (monocytes and lymphocytes) or 12 hours (neutrophils). Next, cells were collected to evaluate the optical absorbance spectrum. The three types of leukocytes exhibited absorbance in the region from 450 to 900 nm, with greater absorbance at wavelengths lower than 570 nm. Lymphocytes had a second region of greater absorbance between 770 and 900 nm. Inflammatory monocytes and lymphocytes showed increased absorbance of blue, green and yellow wavelengths (monocytes), as well as red and infrared wavelengths (monocytes and lymphocytes). Immunoregulatory polarization altered the absorbance of monocytes and lymphocytes very little. Neutrophils treated with LPS or LPS + IL-4 exhibited lower absorbance at wavelengths higher than 575 nm compared to untreated cells. The present findings showed that leukocytes exhibit greater absorbance in regions of the spectrum that have not been much used in photobiomodulation (PBM), and the polarization of these cells can affect their capacity to absorb light. Taken together, these results suggest new perspectives in the use of PBM in the clinical setting depending on the wavelengths and the stage of the inflammatory process. (AU)

• FAPESP's process: 15/21219-6 - Effect of low-intensity laser on gene and protein expression of different phenotypes of macrophages
• Grantee: Kaline de Brito Sousa
• Support Opportunities: Scholarships in Brazil - Master
• FAPESP's process: 13/07502-1 - Effect of laser therapy on gene expression and production of cytokines, chemokines and growth factors involved in muscle repair
• Grantee: Kristianne Porta Santos Fernandes
• Support Opportunities: Regular Research Grants