Phenotypic Alteration of BMDM In Vitro Using Small Interfering RNA

Noreen Halimani; Mikhail Nesterchuk; Irina N Andreichenko; Alexandra A Tsitrina; Andrey Elchaninov; Anastasia Lokhonina; Timur Fatkhudinov; Nataliya O Dashenkova; Vera Brezgina; Timofei S Zatsepin; Arsen S Mikaelyan; Yuri V Kotelevtsev

doi:10.3390/cells11162498

Phenotypic Alteration of BMDM In Vitro Using Small Interfering RNA

Cells. 2022 Aug 11;11(16):2498. doi: 10.3390/cells11162498.

Authors

Affiliations

¹ Vladimir Zelman Center for Neurobiology and Brain Rehabilitation and Center of Life Sciences, Skolkovo Institute of Science and Technology, Moscow 143025, Russia.
² Koltzov Institute of Developmental Biology of Russian Academy of Sciences, 26 Vavilov Street, Moscow 119334, Russia.
³ National Medical Research Center for Obstetrics, Gynecology and Perinatology Named after Academician V.I. Kulakov, Russian Federation, 4 Oparina Street, Moscow 117997, Russia.
⁴ Department of Histology, Pirogov Russian National Research Medical University, Ministry of Healthcare of The Russian Federation, 1 Ostrovitianov Street, Moscow 117997, Russia.
⁵ Department of Histology, Cytology and Embryology, Peoples' Friendship University of Russia, 6 Miklukho-Maklaya Street, Moscow 117198, Russia.
⁶ Scientific Research Institute of Human Morphology, 3 Tsurupa Street, Moscow 117418, Russia.

Abstract

Autologous macrophage transfer is an emerging platform for cell therapy. It is anticipated that conventional macrophage reprogramming based on ex vivo polarization using cytokines and ligands of TLRs may enhance the therapeutic effect. We describe an alternative approach based on small interfering RNA (siRNA) knockdown of selected molecular cues of macrophage polarization, namely EGR2, IRF3, IRF5, and TLR4 in Raw264.7 monocyte/macrophage cell line and mouse-bone-marrow-derived macrophages (BMDMs). The impact of IRF5 knockdown was most pronounced, curtailing the expression of other inflammatory mediators such as IL-6 and NOS2, especially in M1-polarized macrophages. Contrary to IRF5, EGR2 knockdown potentiated M1-associated markers while altogether abolishing M2 marker expression, which is indicative of the principal role of EGR2 in the maintenance of alternative phenotypes. IRF3 knockdown suppressed M1 polarization but upregulated Arg 1, a canonical marker of alternative polarization in M1 macrophages. As anticipated, the knockdown of TLR4 also attenuated the M1 phenotype but, akin to IRF3, significantly induced Arginase 1 in M0 and M1, driving the phenotype towards M2. This study validates RNAi as a viable option for the alteration and maintenance of macrophage phenotypes.

Keywords: EGR2; IRF3; IRF5; TLR4; macrophages; polarization; siRNA.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Biomarkers / metabolism
Interferon Regulatory Factors / genetics
Interferon Regulatory Factors / metabolism
Macrophage Activation*
Mice
Phenotype
RNA, Small Interfering / genetics
RNA, Small Interfering / metabolism
Toll-Like Receptor 4* / genetics
Toll-Like Receptor 4* / metabolism

Substances

Biomarkers
Interferon Regulatory Factors
Irf5 protein, mouse
RNA, Small Interfering
Toll-Like Receptor 4

Grants and funding

This work was conducted under the IDB RAS Government basic research program in 2022 No. 0088-2021-0017. The work was funded by the RFBR grant #19-29-04123, “Enhancement of regenerative capacity of portal macrophages in vivo by RNAi based targeted polarization”, to Yuri Kotelevtsev.