Different Induction of PD-L1 (CD274) and PD-1 (CD279) Expression in THP-1-Differentiated Types 1 and 2 Macrophages

Abstract

Background: Phorbol 12-myristate 13-acetate (PMA)-induced differentiation of human monocytic THP-1 cells is an experimental model for preparing resting macrophages (M 0 ) for cell polarization toward the different functional specializations of macrophages. Methods: In this study, we examined the expression of immune checkpoints by using flow cytometry following multicolor staining. The blockade of immune checkpoint by using neutralizing antibodies was performed to assess their role in PMA-induced THP-1-differentiated macrophages. Results: Upon the inducible macrophage differentiation caused by PMA, increased expression levels of CD11b and CD68 were measured and characterized according to their adherent phenotype accompanied by the generation of cellular complexity. While the cell growth rate was abolished post-differentiation, some cells underwent cell death. Notably, we found increases in the expression of programmed cell death protein 1, also known as PD-1 (CD279), and its ligand PD-L1 (CD274), mainly in differentiated M 0 (CD68 + CD11b + ) macrophages. However, neutralizing PD-L1/PD-1 neither blocked THP-1 cell differentiation toward macrophages nor inhibited macrophage polarization in M 1 and M 2 . In specializing macrophages, a decrease both in CD274 and CD279 was found in M 2 . Conclusion: These results revealed the inducible expression of PD-L1/PD-1 in PMAinduced THP-1-differentiated M 0 macrophages followed by a decrease in M 2 macrophages.

Unveiling the Molecular Mechanisms Driving the Capsaicin-Induced Immunomodulatory Effects on PD-L1 Expression in Bladder and Renal Cancer Cell Lines

“…Firstly, we evaluated the expression of the PD-L1 mRNA and protein levels in T24, 5637 and A498 cells ( Figure 2 A,B), as well as in the THP-1 cell line used as a positive control [ 34 ]. Then, to evaluate the responsiveness to CPS (50 μM), the PD-L1 mRNA and protein levels were evaluated at 12 and 24 h after treatment in T24, 5637 and A498 cells.…”

PD-L1 stimulation can promote proliferation and survival of leukemic cells by influencing glucose and fatty acid metabolism in acute myeloid leukemia

“…THP-1 is of monocytic origin and representative of AML M-5 ( https://en.wikipedia.org/wiki/THP-1_cell_line ) while HL-60 is representative of promyelocytic leukemia M-2 and M-3 ( https://en.wikipedia.org/wiki/HL60 ). According to previous studies, THP-1 and HL-60 cell lines express PD-L1 which can be overexpressed by PMA stimulation [ 9 , 10 ]. 1 × 10 6 of each cell line were seeded in each well of the cell culture plate and stimulated with 50 ng/ml phorbol 12-myristate 13 acetate (PMA, Sigma-Aldrich, St Louis, MO, USA) to increase PD-L1 expression.…”

The Landscape of the Tumor-Infiltrating Immune Cell and Prognostic Nomogram in Colorectal Cancer

“…All the slides were scanned and observed using a Pannoramic MIDI (3DHISTECH) and CaseViewer C.V.2.4. The antibodies CD19, CD163, C-kit, CD68, NOS2, mast cell tryptase, and CD16 were purchased from Servicebio Technology Co. Ltd. DAPI is used to label the nucleus, CD19 is used to label naive B cells, CD163 is used to label M2 macrophages, C-kit labeled the resting mast cells, CD68 labeled cell M0, NOS2 labeled M1 macrophages, mast cell tryptase labeled activated mast cells, and CD16 labeled neutrophils ( Jensen et al, 2014 ; Yamaguchi et al, 2016 ; Lv et al, 2017 ; Sanz et al, 2019 ; Valent et al, 2019 ; Lu et al, 2020 ; Lai et al, 2021 ).…”