Send to

Choose Destination
See comment in PubMed Commons below
Clin Vaccine Immunol. 2009 Nov;16(11):1648-53. doi: 10.1128/CVI.00259-09. Epub 2009 Sep 2.

Cryopreservation decreases receptor PD-1 and ligand PD-L1 coinhibitory expression on peripheral blood mononuclear cell-derived T cells and monocytes.

Author information

Division of Allergy and Immunology, The Joseph Stokes Jr. Research Institute, the Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104, USA.


The B7-CD28 immunoglobulin superfamily of costimulatory and coinhibitory ligands and their cell receptors play a critical role in modulating immune responses. Imbalances in these immune regulatory signals occur in pathological conditions characterized by chronic antigenic stimulation. Clinical studies often rely on the use of cryopreserved peripheral blood mononuclear cells (PBMC) to evaluate cellular immune responses. The impact of cryopreservation on these coinhibitory ligands and their cell receptors is unknown. In our studies, cryopreservation significantly reduced the expression of both PD-1 and PD-L1 on PBMC-derived CD3+/CD8+ T cells and CD45+/CD14+ monocytes obtained from adult control subjects. Blockade of PD-1, PD-L1, and PD-L2 using both freshly isolated and cryopreserved PBMC led to higher levels of phytohemagglutinin (PHA) and Candida-induced gamma interferon (IFN-gamma), interleukin-2 (IL-2), and tumor necrosis factor alpha (TNF-alpha) with no effect on IL-10 production. Coinhibitory signaling blockade of freshly isolated, PHA-stimulated PBMC from normal adult controls and human immunodeficiency virus (HIV)-infected subjects led to increased production of IL-4 and IL-5. Candida-stimulated PBMC preferentially induced IFN-gamma and TNF-alpha production, with reduced production of IL-2 and IL-10. This is in contrast to high levels of IFN-gamma, IL-2, and TNF-alpha production with PHA-stimulated cells. The effects of coinhibitory blockade on PHA and Candida-induced lymphoproliferation were varied, with freshly isolated PBMC from adult control subjects and HIV-infected patients yielding higher levels of lymphoproliferation in response to PD-1/PD-L1 blockade. Immune function studies employing cryopreserved cells may lead to increased T-cell effector cytolytic and regulatory immune responses.

[Indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Support Center