Macrophages mediate psoriasis via Mincle-dependent mechanism in mice

Abstract

Psoriasis is currently considered to be an immune and inflammatory disease characterized by massive immune cells infiltration including macrophages. It has been reported that macrophage-inducible C-type lectin (Mincle) is essential to maintain the pro-inflammatory phenotype of M1 macrophages, however, its role and mechanisms in psoriasis remain largely unknown. A model of psoriasis was induced in mice by a daily topical application of imiquimod for 7 days. Role and mechanisms of Mincle in macrophage-mediated psoriasis were investigated in clodronate liposomes induced macrophage depletion mice followed by adoptively transferring with Mincle-expressing or -knockout (KO) macrophages, and in macrophage specific Mincle knockout mice (Mincleloxp/loxp/Lyz2-cre+/+). Finally, a Mincle neutralizing antibody was employed to the psoriasis mice to reveal the therapeutic potential for psoriasis by targeting Mincle. Mincle was highly expressed by M1 macrophages in the skin lesions of patients and mice with psoriasis. Clodronate liposomes-induced macrophage depletion inhibited psoriasis in mice, which was restored by adoptive transfer with Mincle-expressing macrophages but not by Mincle-KO macrophages. This was further confirmed in macrophage-specific Mincle-KO mice. Mechanistically, macrophages mediated psoriasis via the Mincle-Syk-NF-κB pathway as blocking macrophage Mincle inhibited Syk/NF-κB-driven skin lesions and epidermal injury in vivo and in vitro. We also found that LPS induced Mincle expression by M1 macrophages via the PU.1-dependent mechanism. Most importantly, we revealed that targeting Mincle with a neutralizing antibody significantly improved psoriasis in mice. In summary, our findings demonstrated that macrophages mediate psoriasis in mice via the Mincle-dependent mechanism, targeting Mincle may represent as a novel therapy for psoriasis.

Mincle receptor in macrophage and neutrophil contributes to the unresolved inflammation during the transition from acute kidney injury to chronic kidney disease

“…Moreover, Syk inhibitors and a variety of Chinese patent medicine compounds have demonstrated the ability to suppress Mincle/Syk/NF-kB signaling pathway, consequently mitigating acute kidney inflammation induced by various etiologies ( 41 – 43 ). Furthermore, modulating Mincle activation via targeted manipulation of Mincle gene ( 23 , 44 ) or protein receptor ( 45 , 46 ) emerged as potential therapeutic avenues. Nevertheless, a limitation of this study lies in its exclusive utilization of a murine model of UIR induced AKI.…”

Macrophage Functions in Psoriasis: Lessons from Mouse Models

“…Cutaneous macrophage polarization was also found to be modulated by pentraxin 3 [60]. Finally, chronic stimulation of macrophage-inducible C-type lectin (Mincle), a pattern recognition receptor, preserves macrophage M1 polarization in imiquimod-induced psoriasis [61]. However, inflammatory macrophages may also downregulate psoriatic inflammation by releasing itaconate [62], an immunomodulatory metabolite that physiologically regulates metabolic rewiring and effector functions of activated macrophages [63].…”

Immune cells in the epithelial immune microenvironment of psoriasis: emerging therapeutic targets

“…Additionally, macrophages express macrophage-inducible C-type lectin (Mincle), a pattern recognition receptor primarily used to identify damage-associated molecular patterns (DAMPs) and pathogen-associated molecular patterns (PAMPs). In a mouse model of psoriasis, Mincle-expressing macrophages promote the development of psoriatic skin inflammation ( 126 ). The macrophages participate in the immune response of psoriasis through bidirectional regulation mechanisms.…”