Immune cell activation assessment

Modulation of the immune system function aiming at enhancing the potential of immune cell responsiveness is one promising challenge for cancer therapy. During the immune response, T cells become activated and undergo clonal expansion followed by differentiation into effector cells and induction of cell-mediated cytotoxicity and/or cytokine release.
Understanding and modulating the mechanisms underlying activation, proliferation & clustering of immune cells is key for the development of innovative approaches to promote immune cell function and tackle tumor progression.
One of the most common ways to measure immune cell activation in vitro is the assessment of T cell proliferation upon antigen- or TCR-mediated stimulation. In this respect, Explicyte is offering valuable in vitro PBMC- and T cell-based 96-w plate assays to evaluate the effects of immunomodulatory compounds/antibodies alone and in combination with anti-CD3 antibody, on immune cell activation. By live cell time-lapse imaging, treatment effects are evaluated in a kinetic and phenotypic manner on the immune cell proliferation and clustering, as well as functionally on the release of key effector cytokines.

Illustrative data

PBMC release of key inflammatory cytokines is induced in a dose- and time- dependent manner upon CD3 activation
Key inflammatory cytokines i.e. TNF𝞪, IL2, and IFNγ are shown to be modulated upon human PBMCs stimulation with increasing concentrations of anti-CD3 antibody. While TNFa secretion is efficiently induced at 24h, released IFNg and IL2 levels are time- and dose-dependently increased following anti-CD3 treatment. Cytokine quantification, especially IL2 and IFNg, performed by HTRF, appears valuable surrogate tools to ascertain the PBMC activation.

Key inflammatory cytokines i.e. TNF𝞪, IL2, and IFNγ are shown to be modulated ...

Anti-CD3-induced IFNg release in human PBMCs is optimized by reference anti-PD1 antibodies – Nivolumab and Pembrolizumab
Treatment of anti-CD3-activated PBMCs with increasing concentrations of each of anti-PD1 antibodies (Nivolumab or Pembrolizumab) leads to a significant dose-dependent increase of IFNg release, thereby reflecting further optimization of PBMC activation.

Treatment of anti-CD3-activated PBMCs with increasing concentrations of each of anti-PD1 antibodies ...

L-Kynurenine limits anti-CD3–induced activation of human primary CD4+ T cells, as revealed by cytokine release quantification
Human primary CD4+ T cells are modulated in a dose dependent manner upon anti-CD3 treatment, as illustrated by the production of key inflammatory cytokines – TNFα and IFNγ – quantified by HTRF afer 72 hours of cell culture. Concomitant addition of L-kynurenine with anti-CD3 reveals its dose-dependent immunosuppressive effect. Evaluation of cytokine release upon human primary T cells activation thus represents a valuable approach for immunomodulatory candidate assessment.

Human primary CD4+ T cells are modulated in a dose dependent manner upon anti-CD3 treatment, ...

Assay principle

Assay principle

  • Our 96-w plate assay is performed on immune cells from various origins (PBMCs, purified populations, …)
  • Real time visualization & kinetic monitoring of immune cell activation (proliferation) and aggregation (cell-cell clustering) by live cell imaging.
  • Cell confluence is measured, using an appropriate platform-associated algorithm & image analysis module, as a surrogate of immune cell proliferation.
  • Phenotypic immune cell proliferation and clustering measurement can be multiplexed with additional functional measures i.e. effector cytokine release.