Identification of neutrophil extracellular traps (NETs) in lesions of patients with hidradenitis suppurativa and in vitro evaluation of neutrophils: correlation of NETs with disease severity

• Grant number: 19/08720-9
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: April 01, 2020
• End date: April 30, 2021
• Field of knowledge: Biological Sciences - Immunology - Cellular Immunology
• Principal Investigator: Luciane Alarcão Dias-Melicio
• Grantee: Larissa de Carvalho
• Host Institution: Faculdade de Medicina (FMB). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil

Abstract

Hidradenitis Suppurativa (HS) is a chronic suppurative cutaneous inflammatory disease characterized by perifollicular inflammation especially in areas of skin folds (e.g, armpits and perineum). With the progression of inflammation, cytokine levels are increased, accompanied by an influx of neutrophils, monocytes and mast cells. Neutrophils exert tissue activity from phagocytosis, discharge of enzymes present in their granules and through a mechanism called NETose. This process is characterized by the release of extracellular traps called Neutrophil extracellular traps (NETs), which are composed of nuclear content (decondensed chromatin and histones) and granular content (elastase, myeloperoxidase, among other enzymes with microbicidal activity). Studies have shown that inflammatory processes with intense neutrophilic infiltration present the formation of these extracellular structures, often relating them to the severity of the disease. This mechanism of tissue neutrophilic activity could be proposed for hidradenitis suppurativa. In this context, the objectives of this project will be: to identify the presence of NETs in excised lesions of patients with HS, as well as to identify and quantify the components of these in vitro networks, and to assess the involvement of NETs with disease severity. Ten patients with active HS will be evaluated, from a dermatology outpatient clinic at Botucatu Clinic Hospital, indicated for surgical treatment for excision of the lesions. The excised lesions will be processed for histopathological evaluation and identification of the NET components by confocal microscopy. The NET expression will be correlated with the clinical severity of the patients (Hurley's classification).