As a type of functionally diversified immune cell widely spread throughout the whole body, macrophages play critical roles in the regulation of homeostasis, inflammation, and antitumor immunity in a specific manner. Macrophages are easily transformed into inflammatory (M1) and can also demonstrate effective phagocytosis. The M1 profile is classically associated with the control of bacterial infections. Creative Biolabs offers highly customized assays to induce M1 macrophages and characterize their polarization states.

Introduction to M1 Macrophages

Macrophages are tissue-resident professional phagocytes and antigen-presenting cells, which differentiate from circulating peripheral blood monocytes. They perform significant active and regulatory functions in innate as well as adaptive immunity. Macrophages are plastic leukocytes that perform a vast range of immune- and homeostasis-related functions, with their function and behavior dictated by environmental stimuli. Macrophages can be characterized as being activated into two major phenotypes, classically activated M1 macrophage and alternatively activated M2 macrophage. M1 macrophages comprise immune effector cells with an acute inflammatory phenotype. These are highly aggressive against bacteria, including secretion of pro-inflammatory cytokines, engulfment of foreign entities, generation of reactive oxygen and nitrogen species, and assistance in T-helper type1 (Th1) cell responses to fight infection. In in vitro studies, the M1 profile has been found in response to several bacteria including Salmonella typhimurium, Orientia tsutsugamushi, Legionella pneumophila, Francisella spp., Rickettsia montanensis, Shigella dysenteriae, Bartonella spp., Mycobacterium ulcerans, Chlamydia spp. or Listeria monocytogenes.

Fig.1 The direction of macrophage differentiation in response to different environmental cues.^1,2

M1 Macrophage Polarization Assay at Creative Biolabs

Macrophage Therapeutics Development Platform at Creative Biolabs can generate macrophages by treating isolated bone marrow-derived or peritoneal macrophages with specific stimuli, including secreting inflammatory cytokines, such as tumor necrosis factor–α (TNF-α), interferon-gamma (IFN-γ), and interleukins (IL-1, IL-6, IL-8), and bacterial components such as lipopolysaccharide (LPS), growth factors including granulocyte-macrophage colony-stimulating factor (GM-CSF), or matrix metalloproteinases (MMPs). Moreover, based on surface markers and the distinctly produced cytokines, we also provide the validation of each polarized macrophage. Enzyme-linked immunosorbent assay (ELISA), immunohistochemistry (IHC), flow cytometry (FC) could be conducted to analyze surface markers and cytokines expression upon request. Our polarization protocols are designed to achieve a stable, optimal, and effective regimen for in vitro induction to drive antigen-specific immune responses. Our M1 macrophage polarization assay allows the assessment of cytokine profiles, cell surface receptor expression, scavenging functions, and the ability to activate or suppress T-cell proliferation.

As a long-term expert in the field of macrophage polarization, Creative Biolabs has lots of scientists who are proficient at performing M1 macrophage polarization assay. Our seasoned scientists are pleased to share expertise and experience with our global clients and facilitate their meaningful macrophage polarization studies. For more information, please feel free to contact us and further discuss with our scientists.

References

1. Gao, Jing, Yuanzheng Liang, and Liang Wang. "Shaping polarization of tumor-associated macrophages in cancer immunotherapy." Frontiers in Immunology 13 (2022): 888713.
2. Under Open Access license CC BY 4.0, without modification.