Gago-Lopez et al. found that TSLP, in psoriasis, plays a wide variety of roles; TSLP enhances cell proliferation (via STAT5 pathway activation) and angiogenesis (via vascular endothelial growth factor production). In a murine model, antibodies directed against TSLP led to a positive response in terms of epidermal thickening and vascularization [
38]. Tashiro et al., using cultures of HaCaT cells (immortalized keratinocytes), found that TSLP, in hypoxic conditions, presents reduced levels via the inactivation of its production stimulated by TNF-alpha, via HIF2 and HRE mechanisms (two products involved in the skin response to hypoxemia). It is the authors’ suggestion that targeting these two molecules could lead to lower levels of TSLP and the resolution of lesions both in Pso and AD [
37]. Schaper et al. correlated the levels of TSLP from human skin samples derived from healthy controls, Pso patients and AD patients, noticing that both Pso and AD patients, but mostly Pso patients, presented higher levels of TSLP, especially the inflammation-related isoform rather than the basal one, via histamine release by hyper-active Th2 cells [
34]. Segawa et al. developed a model using HaCaT cells again, demonstrating that EGFR is transactivated via TSLP by TNF-alpha; it is the author’s suggestion that, since anti-TNF drugs may produce many side effects (such as infections), targeting TSLP instead of TNF-alpha could provide the same results with greater benefits [
35]. Chen et al., in a 2021 study, matched healthy controls to AD and Pso patients, showing that it is possible to differentiate two separate groups of Pso patients; the most interesting is the “early onset” group, with high levels of Th2 cells and a high TSLP response. The levels of TSLP were higher than those present in AD, suggesting that different subtypes of Pso could benefit from different types of treatment [
39]. Desmet et al. suggested a novel approach in their study, in which they tried to use RNA interfering molecules, applied topically, to silence the production of several mRNAs among which the mRNA affecting TSLP release. As a result, levels of TSLP dropped, along with the other products, suggesting a possible future treatment for Pso in a 3D model skin [
36].