Below are descriptions of the different services offered by the immunomonitoring core facility.
Standardized processing and isolation of peripheral blood lymphocytes, serum or plasma from tubes or bags, from healthy donors or patients recruited in clinical trials. Isolated mononuclear cells (PBMCs) can be used fresh for functional assays or frozen for analysis at a later date. Isolated cells are stored in the vapour phase of liquid nitrogen tanks. Serum or plasma samples are stored in ultra-low freezers (-80 °C).
Multicolour flow cytometric analysis (up to 27 colours) is used to assess the immunophenotype and the activation status of the different peripheral and tissue cell populations. The data can then be correlated with clinical responses.
Intracellular cytokine staining is used to evaluate the presence of T-cells responsive to an antigen of interest by quantifying the cytokine-producing cells before and after exposure to the antigen. Phenotypic and immune activation markers can also be used to assess immune responses.
Meso Scale Discovery immunoassay kits, which are commercially available, can be used to detect several cytokines by electrochemiluminescence. The analyses can be carried out on different biological substrates such as plasma, serum, cell supernatant, a homogenate of tissues or cerebrospinal fluid. The kits consist of plates coated with ten different antibodies, specific for individual cytokines or other protein analytes. The technology allows for the simultaneous detection of several biomarkers from a single low-volume sample.
ELISPOT is used to quantify the proportion of T cells reactive to a particular antigen. Quantification relies on the secretion of IFN-g by cells that encounter their antigen. The ELISPOT method is highly sensitive, reproducible and simple. It is the gold standard for measuring the specific responses of T cells in several research areas (vaccine development, infectious diseases, allergies, tumours and autoimmune diseases).
Immunofluoresence is used to specifically stain proteins (up to five colours) intracellularly. With immunofluorescence, it is possible to not only observe the presence of a protein, but also its location in the cell or tissue analyzed.
BD Biosciences’ Rhapsody system uniquely combines the analysis of gene expression and surface-protein expression at the cell level. The core facility can provide the following services through the Rhapsody system:
3’ RNA sequencing from single cells (ScRNA-Seq) for targeted and whole transcriptomics
VDJ sequencing for TCR/BCR multiomic assay
Simultaneous characterization of surface proteins and of mRNA expression from single cells (AbSeq)