COVID-19, caused by SARS-CoV-2 virus, emerged as a pandemic disease posing a severe threat to global health. To date, sporadic studies have demonstrated that innate immune mechanisms, specifically neutrophilia, NETosis, and neutrophil-associated cytokine responses, are involved in COVID-19 pathogenesis; however, our understanding of the exact nature of this aspect of host–pathogen interaction is limited. Here, we present a detailed dissection of the features and functional profiles of neutrophils, dendritic cells, and monocytes in COVID-19. We portray the crucial role of neutrophils as drivers of hyperinflammation associated with COVID-19 disease via the shift towards their immature forms, enhanced degranulation, cytokine production, and augmented interferon responses. We demonstrate the impaired functionality of COVID-19 dendritic cells and monocytes, particularly their low expression of maturation markers, increased PD-L1 levels, and their inability to upregulate phenotype upon stimulation. In summary, our work highlights important data that prompt further research, as therapeutic targeting of neutrophils and their associated products may hold the potential to reduce the severity of COVID-19.

Dendritic cells (DCs) are specific antigen‐presenting cells that play critical roles in the initiation and polarization of immune responses. DCs residing in the lungs might be detected in the bronchoalveolar lavage fluid (BALF). We analysed DC compartment in the peripheral blood and BALF of patients with allergy and in controls. Plasmacytoid and four distinct subsets of myeloid DCs [characterized by the expression of blood dendritic cell antigen (BDCA)‐1⁺ and ‐3⁺ and CD16 positivity or negativity] were detected in both tested compartments. We further evaluated the expression of C‐type lectins [mannose receptor (MR), dendritic cell‐specific intercellular adhesion molecule‐3‐grabbing non‐integrin (DC‐SIGN) and dendritic and epithelial cells (DEC)‐205] relevant to the pathogenesis of asthma. Interestingly, we found a selective increase in the frequency of myeloid DC‐expressing BDCA‐3 and MR particularly in BALF from allergic patients. Specific and highly statistically significant increase in BDCA‐3⁺ and/or MR⁺ DCs brings a novel characteristic to BAL analysis in allergic patients.

Three to four dominant seed-transporting ant species of different size categories (Tetramorium caespitum, Lasius niger, Formica rufibarbis/Formica pratensis) on the plateau of abandoned ore sedimentation basin (tailings containment) were studied as pioneer and subsequent colonisers of this industrial waste deposit, from the viewpoint of their functioning in plant seed dispersal. We examined the role of ants in primary vegetation succession. Experiments of seed removal by ants with plant species found within close proximity of tailings were related to the succession. Ant activity generates a considerable shift in the quality of the colonised surface, as they collectively act as ecosystem engineers