Article

Effect of SIVmac infection on plasmacytoid and CD1c+ myeloid dendritic cells in cynomolgus macaques.

CEA, Service d'Immuno-Virologie, DSV/iMETI, IPSC, Fontenay-aux-Roses, France.
Immunology (impact factor: 3.32). 07/2008; 124(2):223-33. DOI:10.1111/j.1365-2567.2007.02758.x pp.223-33
Source: PubMed

ABSTRACT Dendritic cells (DCs) are known to be essential for the induction and regulation of immune responses. Non-human primates are essential in biomedical research and contribute to our understanding of the involvement of DCs in human infectious diseases. However, no direct single-platform method for quantifying DC precursors has yet been optimized in macaques to give accurate absolute blood counts of these rare-event cell populations in the blood. We adapted a rapid whole-blood assay for the absolute quantification of DCs in cynomolgus macaques by four-colour flow cytometry, using a single-platform assay compatible with human blood. Cynomolgus macaque plasmacytoid DCs (pDCs) and CD1c(+) myeloid DCs (CD1c(+) mDCs) were quantified in the blood of 34 healthy macaques and the results obtained were compared with those for blood samples from 11 healthy humans. In addition, circulating absolute numbers of pDCs were quantified in cynomolgus macaques chronically infected with SIVmac. During infection, pDC counts decreased whereas circulating CD1c(+) mDC counts increased. Information regarding absolute pDC and mDC counts in non-human primates may improve our understanding of the role of these cells in SIV/HIV infection and in other infectious diseases.

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Keywords

11 healthy humans
 
34 healthy macaques
 
absolute quantification
 
accurate absolute blood counts
 
biomedical research
 
blood samples
 
Cynomolgus macaque plasmacytoid DCs
 
cynomolgus macaques
 
cynomolgus macaques chronically
 
direct single-platform method
 
four-colour flow cytometry
 
human blood
 
human infectious diseases
 
infectious diseases
 
non-human primates
 
pDCs
 
quantifying DC precursors
 
rapid whole-blood assay
 
rare-event cell populations
 
single-platform assay compatible