Quantitative Expression of C-Type Lectin Receptors in Humans and Mice

C-type lectin receptors and their adaptor molecules are involved in
the recognition of glycosylated self-antigens and pathogens.
However, little is known about the species-and organ-specific
expression profiles of these molecules. We therefore determined the
mRNA expression levels of Dectin-1, MR1, MR2, DC-SIGN, Syk, Card-9,
Bcl-10, Malt-1, Src, Dec-205, Galectin-1, Tim-3, Trem-1, and DAP-12
in 11 solid organs of human and mice. Mouse organs revealed lower
mRNA levels of most molecules compared to spleen. However, Dec-205
and Galectin-1 in thymus, Src in brain, MR2, Card-9, Bcl-10, Src,
and Dec-205 in small intestine, MR2, Bcl-10, Src, Galectin-1 in
kidney, and Src and Galectin-1 in muscle were at least 2-fold
higher expressed compared to spleen. Human lung, liver and heart
expressed higher mRNA levels of most genes compared to spleen.
Dectin-1, MR1, Syk and Trem-1 mRNA were strongly up-regulated upon
ischemia-reperfusion injury in murine kidney. Tim3, DAP-12, Card-9,
DC-SIGN and MR2 were further up-regulated during renal fibrosis.
Murine kidney showed higher DAP-12, Syk, Card-9 and Dectin-1 mRNA
expression during the progression of lupus nephritis. Thus, the
organ-, and species-specific expression of C-type lectin receptors
is different between mice and humans which must be considered in
the interpretation of related studies.