Voie d'immunisation et séquence d'administration de l ... - TEL

tel-00827710, version 1 - 29 May 2013
characterized in mice as well as in humans. pDCs are strongly implicated in innate immunity
due to their capacity to secrete high amounts of type I Interferons (IFN) and, in some studies,
demonstrated ability to present antigen (Villadangos and Young, 2008). However, for the
remainder of this introduction, I will focus on cDCs. Collectively, cDCs is an heterogeneous
group of DCs that can be divided into the broad groupings of lymphoid tissue-resident DCs
and peripheral, migratory DCs (Heath and Carbone, 2009). In the spleen, 3 further cDC
subsets have been described based on CD8 and CD4 expression: the CD8α + DCs, the CD8α -
DCs and the double negative DCs (Vremec et al., 2000). However in draining lymph nodes,
other subsets can be observed that correspond to the migratory DC populations that reside in
tissue and have the ability to migrate to lymphoid organs upon activation. Using the skin-
draining lymph node as an example, 3 additional subsets are found: the Langherans cells that
are normally found in the epidermis, the classical dermal CD11b + CD103 - DCs, and the
dermal CD11b low CD103 + DCs (Ginhoux et al., 2007). Interestingly the 2 subsets CD11b +
CD103 - DCs, and the CD11b low CD103 + DCs are also found in other peripheral tissues such as
the lung (Sung et al., 2006) and the gut (Annacker et al., 2005) where they seem to have the
same specialized function, regulating the immune response. In contrast, the Langherans cells
are specific to the skin. An additional subset that is not present at steady state, but that appears
under conditions of inflammation is the inflammatory monocyte-derived DCs.
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