CpG oligonucleotides induce strong humoral but only weak CD4+ T cell responses to protein antigens in rhesus macaques in vivo

Ruhr-Universität Bochum, Bochum, North Rhine-Westphalia, Germany
Vaccine (Impact Factor: 3.62). 06/2005; 23(25):3310-7. DOI: 10.1016/j.vaccine.2005.01.077
Source: PubMed


Oligonucleotides containing CpG motifs (CpG ODN) are strong adjuvants for humoral immune responses but data on cellular immune responses in primates are scarce. Rhesus macaque blood contained similar numbers of plasmacytoid dendritic cells and B cells, the key sensors of CpG ODN, as human blood, and these cells were activated by CpG-A and CpG-B in vitro. In vivo, both ODNs induced equal plasma levels of interferon-inducible protein 10 and similarly enhanced antibody responses following i.m. injections of the ODNs, protein antigen, and aluminium hydroxide into rhesus macaques, whereas antigen-specific CD4(+) T cell responses were only slightly increased by CpG ODN.

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    • "The cell surface and intracellular cytokine staining was evaluated using flow cytometry (31,32). Briefly, cell suspensions from immunized mice were harvested from the spleen as described previously, then splenocytes were aliquoted into six-well round-bottom plates at 1×106 cells/well and stimulated with 10 μg/ml OVA in the presence of 5 μM brefeldin A (10 μg/ml; Sigma) for 24 h. "
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