For instance, both interferon (IFN)α, which is produced as a result of signaling via toll-like receptor (TLR)3, or direct TLR3 signaling using Poly:IC down regulates MerTK expression (as do LPS and IFNγ), but at the same time induces Axl expression in human macrophages, which may facilitate efferocytosis during viral infections (45). This evidence concerns the gene TLR3 and viral infectious disease.