Caracterização de receptores RIG e do Inflamassoma NLRP3 nas lesões cutâneas do Monkeypox Virus (MPXV)

Abstract

Introduction: Monkeypox (Mpox) is an infection caused by Monkeypox virus (MPXV), a virus belonging to the Orthopoxvirus genus, and represents a zoonosis with a history of endemic circulation in West and Central Africa and recent dissemination to Europe and the Americas, including Brazil. The disease is characterized by vesicular skin lesions with an intense inflammatory response, in which the participation of cellular receptors of innate immunity, such as the RIG-I type and the NLRP3 inflammasome, has not yet been characterized. Objective: To characterize the expression of RIG-I receptors and the NLRP3 inflammasome in Mpox skin lesions. Methods: Skin biopsy samples from 15 participants were morphologically examined and subjected to immunohistochemical analysis for semi-quantification of RIG-I receptors and NLRP3 inflammasome. Results: The most common observed epidermal alterations were hyperkeratosis (73.33%), spongiosis (53.33%) and vacuolization of basal keratinocytes (66.67%). The dermis showed reticular degeneration (60.0%) and predominantly mild/moderate inflammatory infiltrate with perivascular and periadnexal location. The immunohistochemistry revealed overexpression of the markers RIG-1 (73.33%), MDA5 (73.33%) and IL-18 (100.0%) in the samples, in addition to basal expression of the markers NLRP3, Caspase-1 and IL-1β. Conclusion: The Mpox skin lesion shows a spongiotic, perivascular and perianexial inflammatory pattern and an innate immune response characterized by the predominant involvement of RIG-1 and MDA5 receptors.