?(Fig.2B).2B). in comparison with healthy controls. Patients with BD had elevated numbers of LDN and lower number of NDN compared with healthy controls. However, both neutrophil subsets showed the same reduced ROS production and phagocytic function as total neutrophils in both groups. Conclusion Our novel findings indicate that the neutrophil population in BD is heterogeneous and the increased number of LDN in combination with greater NET production may contribute to the inflammatory response and pathogenesis. Supplementary Information The online version contains supplementary material available at 10.1186/s12950-022-00302-1. [2] The prevalence rate of BD in the UK is 14.61 (95% CI 13.35C15.88) per 100,000 population [3]. Between 50 and 90% of BD patients have intraocular involvement manifestations, such as recurrent, non-granulomatous panuveitis, hypopyon and retinal vasculitis. Posterior segment inflammation of the eye also involves occlusion of retinal veins and later occlusion of the retinal arterial circulation that can lead to irreversible blindness [4].. Neutrophils are a major group of the immune cell population that are present in a resting state in the circulation of healthy individuals and play a dynamic role within an inflammatory response. Neutrophils are phagocytic cells that ingest infectious agents, such as bacteria and fungi, that are destroyed by the production of reactive oxygen and nitrogen species (ROS and NOS) known as oxidative burst, with the release of neutrophil granule components and the production of elastase [5]. The build-up of oxidative stress and the production of oxygen radicals may cause DNA damage, oxidation of lipids, lipoproteins and proteins and can be linked to mutations in immunoglobulins that have been implicated in the formation of inflammatory diseases [6]. Neutrophil extracellular traps (NET) are web-like structures composed of cytosolic and granule proteins of decondensed chromatin, produced to protect against LAMC1 antibody infection by pathogens [7]. NET proteins are derived from primary granules (neutrophil elastase and myeloperoxidase), secondary granules (lactoferrin and pentraxin 3) and tertiary granules (matrix metalloproteinase). NET formed by activated neutrophils trap bacteria and other pathogens leading to their Seocalcitol destruction [8]. Neutrophil hyperfunction, in particular increased neutrophil chemotaxis, has been linked with BD for over 40?years [9]. Neutrophils have been reported in biopsies of active oral and genital ulcers, the skin lesions of erythema nodosum and the skin pathergy test [10, Seocalcitol 11]. Neutrophils from HLA-B*51-positive patients showed an increase in the chemotactic response toward several stimuli suggesting that the HLA region can exert a regulatory control on PMN functions [12, 13]. T cells and monocytes activated via Toll-like receptor-2 (TLR2) have been implicated in releasing neutrophil stimulating molecules that induce chemotaxis in neutrophils from patients with BD and healthy Seocalcitol controls in response Seocalcitol to several stimuli [14]. Neutrophils from BD patients display elevated superoxide production and increased lysosymal enzyme production in response to different stimuli [15, 16]. Recent studies Seocalcitol have shown increased NET production by neutrophils from patients with BD [17, 18]. Increased expression of CD11b possibly as a result of the interaction of neutrophils with activated platelets, enhanced platelet-neutrophil aggregate formation [19].. The neutrophil-lymphocyte ratio was significantly higher in patients with active BD, although not significantly different between patients with or without thrombosis [20]. Certain patients with BD can be successfully treated with colchicine which is a neutrophil inhibitor [21, 22]. Neutrophils were considered to be a homogenous population of differentiated cells with a distinct and conserved function. However, increasing evidence.