A powerful way to measure the effect of your therapeutic candidate on T cell activation

    Antibody analytics offers a range of in vitro MLR assay set ups which allow the assessment of immunomodulatory drugs on T cell activation. Immunosuppressive or activating molecules can be incorporated into the assay, providing information on their mode of action. We will work in collaboration with you to create an intelligently designed experimental set up to ensure you get the answers to your scientific questions.

Want to learn more about our MLR model?
Contact one of our team now to see how we can help

What is Mixed Lymphocyte Reaction?

MLR relies on the ability of T cells to recognize cells from another individual as ‘non-self’ due to differences in HLA haplotypes. The MLR assay is an in vitro simulation of this phenomenon: T cells (responders) are mixed with antigen presenting cells (stimulators) from different (allogeneic) donors. Using their T cell receptors (TCRs), T cells scan the surface of the other cells, recognizing MHC-peptide complexes on allogeneic cells as foreign. This recognition induces potent activation of the T cell.

One-Way MLR

T cells from one donor are mixed with antigen presenting cells (APCs) from an alternative donor. This uni-directional stimulation provides a simple system in which the activation of the T cells can be measured in a background free model.

Two-Way MLR

Two PBMC populations are combined, each effectively containing both responder and stimulator cells. The activation of T cells within both populations can be measured simultaneously.

Find out more ways we can support your molecule

What is a typical MLR assay setup?
In a one way MLR, APCs are generated from one donor by differentiating CD14+ monocytes in culture to create monocyte differentiated dendritic cells (mo-DCs).

Allogeneic T cells isolated from PBMCs from a different donor are incubated with mo-DCs in culture over 3-7 days.

The activation of T cells can be measured by determining cytokine production (Luminex or ELISA), proliferation by way of a fluorescent dye or thymidine analogue incorporation (flow cytometry).

The phenotype of both the T cells and the APCs can be determined by flow cytometry and assessed for activation markers, co-stimulatory molecules, checkpoint inhibitors or intracellular protein expression.

Looking for a more technology based solution?

Responder Cells
The responder cell population can take the form of PBMCs or for a purer cellular system. Enriched CD3+ T cells, CD4+ or CD8+ T cells, or CD4+ Tregs can be purified for use in the assay.
Stimulator Cells
Mo-DCs provide a defined cellular means of antigen presentation and can be readily produced in vitro. Where relevant to the scientific questions to be addressed, mo-DCs can be replaced with PBMCs or other immune cells.

In consultation with you, we will determine the most appropriate MLR assay design to answer your scientific questions.

Why trust us to perform your Mixed Lymphocyte Reaction?

  • Pre-screened, HLA-mismatched donor pairs, available for immediate use (>70 donors available)
  • Medium-throughput assay format facilitating the assessment of your molecules in isolation or combination
  • In addition to experimental execution, we provide analysis and interpretation of your results by our expert immunologists
  • Multiple readouts; T cell proliferation, cytokine production and cell phenotyping

Donor pairing is crucial for an effective MLR reaction, the strength of the T cell response relies on the degree of mismatch between the responder and stimulator cells. Here at Antibody Analytics, we have cell banks of pre-screened donor pairs which have been pre-selected to provide optimal assay conditions. Leukapheresis material is used to ensure large quantities of cells, this means we can use the same donor material throughout your study, providing you with consistent results.

Got a Question?

Other Assays you may be interested in


In a results-driven manner, our expert immunologists can work with you to develop further immunological assays to interrogate the data arising from the cytokine release assay.


Our assay is readily adaptable to address your scientific questions. The T cell population to be suppressed can be selected from PBMCs, pan-T cells, CD4+ or CD8+ T cells as required.


MLR assays can take a variety of formats that should first be defined and optimised based on the requirements and the endpoints of the assay.


Our capabilities allow us to support early screening activities all the way through to the development of lot release potency assay methods.

Stay in touch with our R&D in this space and request further info