CNR2 and erythema multiforme: Intriguingly, in EM lesions from CNR1 k/o and CNR2 k/o, we saw significantly elevated expression of monocytes/macrophages (Figure 7D), stromal cells (Figure 7E), and hallmarks of EM such as proliferation and vascularization (Figure 7F) demonstrating an altered microenvironment in the absence of these receptors.