Immune Function & Modulation Assays
Mixed Lymphocyte Reaction (MLR) Assay
Does your compound modulate the dendritic-cell/T-cell immune synapse — amplifying an anti-tumor T-cell response, or relieving immunosuppression?
Our allogeneic MLR assay reads IFN-γ release as a surrogate of CD4+ T-cell activation, benchmarked against checkpoint inhibitors and adenosine-axis reference compounds.
MLR assay format and readouts
- Format
- 96-well plate
- Model
- Allogeneic co-culture — primary CD4+ T cells (responder) with monocyte-derived dendritic cells (stimulator)
- Readouts
- IFN-γ release by HTRF as a surrogate of T-cell activation
- Standards
- Checkpoint inhibitors (anti-PD-1 nivolumab, anti-PD-L1 atezolizumab) and adenosine-receptor ligands (agonist to suppress, antagonist to relieve)
- On request
- Dendritic-cell immunophenotyping by flow cytometry, IL-8/IL-12/IL-10 for DC function, proteomics, and transcriptomics
MLR in allogeneic human mDC/CD4+ T-cell co-cultures from independent donor pairs is enhanced by PD-1 inhibition and limited by adenosine. Peripheral-blood monocyte-derived mature dendritic cells are co-cultured with allogeneic CD4+ T cells; IFN-γ (A) and IL-2 (B) released into the supernatants are quantified by HTRF. The T-cell–stimulating capacity of mature DCs rises after PD-1 blockade with nivolumab (a higher MLR response) and is sharply reduced under adenosine treatment.
Imane Nafia, PhD
Chief Scientific Officer, Explicyte
Assay principle
How the MLR assay works
1
Establish the allogeneic co-culture
Monocyte-derived dendritic cells from one donor (stimulator) are co-cultured with CD4+ T cells from a second, unrelated donor (responder) in 96-well plates, driving an allogeneic T-cell response.
2
Introduce the test compound
Your compound is added during dendritic-cell differentiation and/or maturation, or at the co-culture stage — letting you probe where in the dendritic-cell/T-cell synapse it acts.
3
Quantify the T-cell response
Cytokines released during DC maturation and co-culture — IFN-γ, IL-2, IL-8, IL-12, IL-10 — are measured by HTRF or LEGENDplex™, with IFN-γ read as the primary surrogate of T-cell activation.
4
Resolve the mechanism of action
Surface-marker phenotyping and signaling-pathway analysis pin down how the compound shifts dendritic-cell function and the resulting T-cell response.
Illustrative MLR data
MLR assay for cancer immunotherapies: example results
PD-1 blockade enhances the allogeneic MLR response
Monocyte-derived mature dendritic cells co-cultured with allogeneic CD4+ T cells; IL-2 (A) and IFN-γ (B) in the supernatants quantified by HTRF. Mature DCs drive a measurable MLR response that increases further after PD-1 blockade with nivolumab.
Adenosine impairs dendritic-cell function, relieved by receptor antagonism
Monocyte-derived DCs were challenged with adenosine, with or without an adenosine-receptor antagonist. Flow cytometry profiled DC differentiation and maturation (A); DC and co-culture supernatants were assayed by HTRF for IL-10 and IFN-γ (B).
Adenosine skewed DCs toward a CD1a-low CD14+ phenotype and suppressed the MLR — more IL-10 from DCs, less IFN-γ from T cells — an effect reversed by the antagonist, confirming it is adenosine-receptor–mediated.
Making a difference as a preclinical CRO in oncology
Why work with Explicyte
Deep immuno-oncology experience
>100 in vitro campaigns over the past ten years, and 30+ peer-reviewed publications in immuno-oncology journals.
A dedicated PhD study director
One study director, PhD-level, owns your program from experimental design through the final report discussion.
Independent donor pairs
Characterized donors and controlled differentiation, run across unrelated responder–stimulator pairs so an effect holds beyond one donor.
Mechanism, not just a readout
Immunophenotyping, cytokine multiplexing, proteomics, and transcriptomics locate where your compound acts — on DC function, the T-cell response, or both.
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 MLR assay
Whether you're testing an immune checkpoint inhibitor, an agonist antibody, or a small molecule acting on an immunosuppressive pathway, we'll build an MLR study around your mechanism and endpoints — from single-agent screening to combination potency profiling.
Answers about MLR assay
Frequently asked questions
What does a mixed lymphocyte reaction (MLR) assay measure?
It measures how a test compound modulates the dendritic-cell/T-cell immune synapse. In an allogeneic co-culture of CD4+ T cells (responder) and monocyte-derived dendritic cells (stimulator), IFN-γ release reports the strength of the resulting T-cell activation — rising when a compound amplifies the response and falling when it suppresses it.
What cells and format does Explicyte use?
Primary CD4+ T cells from one donor and monocyte-derived dendritic cells from a second, unrelated donor, co-cultured in 96-well plates. The unrelated donors create the allogeneic mismatch that drives the T-cell response.
Which readouts are available?
IFN-γ by HTRF is the primary readout, as a surrogate of T-cell activation. Depending on the question, we also measure IL-2, IL-8, IL-12 and IL-10, phenotype the dendritic cells by flow cytometry, and add proteomic or transcriptomic profiling to resolve mechanism.
What reference compounds do you benchmark against?
Checkpoint inhibitors — anti-PD-1 (nivolumab) and anti-PD-L1 (atezolizumab) — as amplifying controls, and adenosine-receptor ligands as the immunosuppressive axis: an agonist to suppress the response, an antagonist to relieve it.
Which therapeutics can the assay assess?
Both biologics and small molecules, as single agents or in combination — including immune checkpoint inhibitors, agonist antibodies, and compounds acting on immunosuppressive pathways such as the adenosine axis.
Can the assay distinguish where a compound acts?
Yes. Compounds can be introduced during dendritic-cell differentiation, during maturation, or at co-culture, and DC phenotype can be read before co-culture. That separates effects on dendritic-cell function from effects on the T-cell response itself.
How is donor variability handled?
The assay is run across independent donor pairs, so a compound’s effect is observed beyond a single responder–stimulator combination rather than in one genetic background.
What kinds of studies is the MLR suited to?
Screening, potency profiling, and functional characterization of candidate compounds — from an initial single-agent read through combination studies with immune checkpoint inhibitors.