Cell biology 

Overview

PepTivator® CMV pp65 is a peptide pool that consists mainly of 15-mer peptides with 11–amino acid (aa) overlap, covering the complete sequence of the pp65 protein of human cytomegalovirus (UniProt ID: P06725).
PepTivator peptide pools have been developed for the efficient in vitro stimulation of antigen-specific CD4+ and CD8+ T cells, as peptides of 15–aa length with 11–aa overlap represent an optimized solution for stimulating both CD4+ and CD8+ T cells in various applications.
Quantitative, phenotypical, or functional analysis of pp65-specific T cell immunity can provide important information on the natural course of immune responses in healthy or immunocompromised individuals.PepTivator CMV pp65-HT is a peptide pool lyophilized in the wells of a 96-well plate, allowing stimulation and analysis of cells directly on the plate. The convenient 96-well format, composed of 12 individually removable strips of 8 wells each allows for easy and flexible experimental set-up, different antigens can be combined by assembling different strips. A control can also be added easily by using strips from the Control plate (12x8).

Background information

CMV pp65 (65 kDa lower matrix phosphoprotein), also known as glycoprotein 64 or UL83, is a virion tegument protein and the main component of the enveloped subviral particle. CMV pp65 is an immunodominant target of CD4+ and CD8+ T cell responses to CMV. CMV pp65-specific T cells predominantly produce inflammatory cytokines, such as IFN-γ, IL-2, and TNF-α.

Downstream applications

The in vitro stimulation of pp65-specific CD4+ and CD8+ T cells with PepTivator CMV pp65 causes the secretion of effector cytokines and the upregulation of activation markers, which then allow the detection and isolation of pp65-specific T cells:

• Detection and analysis of CMV pp65-specific CD4+ and CD8+ effector/memory T cells in PBMCs by MACS® Cytokine Secretion Assays, intracellular staining, or other technologies.
• Isolation of viable CMV pp65-specific CD4+ T cells with the CD154 MicroBead Kit, or of CD4+ and CD8+ T cells using the CD137 MicroBead Kit or MACS Cytokine Secretion Assay - Cell Enrichment and Detection Kits. Subsequently, cells can be expanded for generation of T cell lines.
• Generation of CMV pp65-specific CD4+ and CD8+ effector/memory T cells from naive T cell populations.
• Pulsing of antigen-presenting cells for research on dendritic cell vaccination.