TNF and psoriasis: Targeting alternative costimulatory molecules, such as 4-BBL or others in the tumor necrosis factor superfamily of receptors and ligands, may be a treatment option for preventing psoriasis relapse.44,45 Understanding the mechanisms that regulate the reactivation of TRM cells and their key interactions with innate immune and stromal cell populations in recurring lesions may help identify new treatment strategies for durable remission in psoriasis and potentially other diseases.