Immune Function & Modulation Assays
M1 & M2 macrophage assays
Can your compound repolarize M2 macrophages to M1, or relieve M2-mediated immunosuppression?
Our M1/M2 assays read that out with IFN-γ as the surrogate of T cell activation.
Macrophage assays' format and readouts
- Format
- Miniaturized culture plates
- Models
- Monocyte-derived M1 or M2 macrophages, alone or co-cultured with autologous activated PBMCs or CD4+ T cells
- Readouts
- IFN-γ as a surrogate of T cell activation; macrophage cytokine release (IL-6, IL-10, IL-12)
- Standards
- p38 MAPK inhibitor, STAT3 inhibitor, PI3K inhibitor; nivolumab (anti-PD-1), atezolizumab (anti-PD-L1), ipilimumab (anti-CTLA-4)
- On request
- Extended macrophage and effector-cell cytokine profiling, flow-cytometry immunophenotyping, proteomics, transcriptomics
M2 macrophages
M1 macrophages
Macrophages span functionally opposite states: M1 drive inflammation, while M2 resolve it and suppress T cells — through checkpoint engagement (e.g., PD-L1), anti-inflammatory cytokines (IL-10, TGF-β), and immunosuppressive metabolism, the same playbook as tumor-associated macrophages (TAMs). Our M2 suppression assay co-cultures monocyte-derived M2 macrophages with activated CD4+ T cells and reads IFN-γ to score how a compound modulates them.
Getting a genuine, stable M2 phenotype is where most macrophage work falls down. We anchor polarization to CD86, CD163, and the IL-6/IL-10 balance, so when a compound shifts the state we know it’s the drug, not drift in the model.
Imane Nafia, PhD
Chief Scientific Officer, Explicyte
Assay principle
How our macrophage assays work
1
Differentiate & polarize
Monocytes are isolated from healthy-donor PBMCs and polarized in vitro into M1 or M2 macrophages.
2
Co-culture with T cells
M1 or M2 macrophages are co-cultured with autologous activated PBMCs or CD4+ T cells. Test compounds can be added during macrophage polarization, during the co-culture, or across both windows — as single agents or in combination.
3
Read out
IFN-γ is quantified as a surrogate of T cell activation, alongside macrophage cytokine release (IL-6, IL-10, IL-12).
4
Interpret
Effects are benchmarked against reference standards — pathway inhibitors and checkpoint antibodies — to place your compound’s repolarizing or suppression-relieving activity.
Illustrative macrophage data
Macrophage polarization and M2 suppression: example results
Mirrored M1/M2 phenotypes
M1 and M2 macrophages are functionally opposite subsets with mirrored phenotypes: M1 are CD86-high, CD163-negative, IL-6-high, IL-10-low; M2 are CD86-low, CD163-positive, IL-6-low, IL-10-high.
Repolarizing M2 through signaling pathways
The M2 IL-6-low / IL-10-high profile drives T cell suppression via JAK/STAT and SMAD/p38 MAPK.
Adding a STAT3 or p38 MAPK inhibitor during polarization reverses that profile and relieves M2 suppression, seen as recovered IFN-γ in PBMC/M2 co-culture.
Relieving M2 suppression with checkpoint blockade
M2 suppression runs through PD-1/PD-L1 and CTLA-4/CD80–CD86. Nivolumab, atezolizumab, or ipilimumab restore T cell activation in PBMC/M2 co-cultures, and further promote the M1-driven stimulation of T cell responses.
Making a difference as a preclinical CRO in oncology
Why work with Explicyte
Deep immuno-oncology experience
More than 100 in vitro campaigns over ten years, behind 30-plus peer-reviewed publications in immuno-oncology.
A dedicated PhD study director
A single PhD-level study director owns your program from experimental plan through final-report discussion.
Reference-anchored design
Every readout is benchmarked against pathway-inhibitor and checkpoint-antibody controls, so your compound’s effects stay interpretable.
Mechanism-resolving readouts
IFN-γ plus macrophage cytokine panels, extendable to flow immunophenotyping, proteomics, and transcriptomics for deeper mechanism.
Paul Marteau, PharmD (study director), Imane Nafia, PhD (CSO), Loïc Cerf, MSc (COO), Alban Bessède, PhD (founder, CEO), Jean-Philippe Guégan, PhD (CTO)
Contact our team
Discuss your macrophage study
Tell us about your macrophage program — polarization, M2 suppression, or a combination strategy — and we'll propose a fit-for-purpose study.
Answers about macrophage assays
Frequently asked questions
What does the M1/M2 macrophage assay measure?
Whether a test compound shifts macrophage polarization between M1 and M2 states, and how that changes T cell activation, read as IFN-γ, alongside macrophage cytokines (IL-6, IL-10, IL-12).
How are the macrophages produced?
Monocytes are isolated from healthy-donor PBMCs and differentiated in vitro into M1 or M2 macrophages, then used alone or co-cultured with autologous activated PBMCs or CD4+ T cells.
What is the M2 suppression assay?
It co-cultures monocyte-derived M2 macrophages with activated CD4+ T cells (or PBMCs) and quantifies IFN-γ as a surrogate of T cell activation, to test whether a compound relieves M2-mediated suppression.
How do M1 and M2 readouts differ?
M1 macrophages boost T cell activation and raise IFN-γ in co-culture; M2 macrophages suppress it and lower IFN-γ. Compounds are scored by how far they move each direction.
Which reference standards do you run?
Signaling-pathway inhibitors (p38 MAPK, STAT3, PI3K) and checkpoint antibodies: nivolumab (anti-PD-1), atezolizumab (anti-PD-L1), and ipilimumab (anti-CTLA-4).
Can you test compounds in combination?
Yes. Candidates run as single agents or in combination, which suits checkpoint-plus-pathway strategies aimed at repolarizing M2 macrophages or relieving their suppression of T cells.
How do these assays relate to tumor-associated macrophages (TAMs)?
M2 macrophages share key features with TAMs — checkpoint engagement, anti-inflammatory cytokines, and immunosuppressive metabolism — so the M2 suppression assay is a practical in vitro proxy for TAM-directed compounds.
What additional analyses are available on request?
Extended macrophage and effector-cell cytokine profiling, flow-cytometry immunophenotyping, proteomics, and transcriptomics, depending on the mechanism you need to resolve.