The current work aimed to synthesize selenium and zinc nanoparticles using the aqueous extract of Ephedra aphylla as a valuable medicinal plant. The prepared nanoparticles were characterized by TEM, zeta potential, and changes in the phytochemical constituents. Hence, the phenolic, flavonoid, and tannin contents were reduced in the case of the prepared samples of nanoparticles than the original values in the aqueous extract. The prepared extract of Ephedra aphylla and its selenium and zinc nanoparticles showed high potency as antioxidant agents as a result of the DPPH^• assay. The samples were assessed as anticancer agents against six tumor cells and a normal lung fibroblast (WI-38) cell line. The selenium nanoparticles of Ephedra aphylla extract revealed very strong cytotoxicity against HePG-2 cells (inhibitory concentration (IC₅₀) = 7.56 ± 0.6 µg/mL), HCT-116 cells (IC₅₀ = 10.02 ± 0.9 µg/mL), and HeLa cells (IC₅₀ = 9.23 ± 0.8 µg/mL). The samples were evaluated as antimicrobial agents against bacterial and fungal strains. Thus, selenium nanoparticles showed potent activities against Gram-negative strains (Salmonella typhimurium, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Escherichia coli), Gram-positive strains (Bacillus cereus, Listeria monocytogenes, Staphylococcus aureus, and Staphylococcus epidermidis), and the fungal strain Candida albicans. In conclusion, the preparation of nanoparticles of either selenium or zinc is crucial for improved biological characteristics.

Epicutaneous application of Aldara cream containing the TLR7 agonist imiquimod (IMQ) to mice induces skin inflammation that exhibits many aspects of psoriasis, an inflammatory human skin disease. Here we show that mice depleted of B cells or bearing interleukin (IL)-10-deficient B cells show a fulminant inflammation upon IMQ exposure, whereas ablation of NFATc1 in B cells results in a suppression of Aldara-induced inflammation. In vitro, IMQ induces the proliferation and IL-10 expression by B cells that is blocked by BCR signals inducing NFATc1. By binding to HDAC1, a transcriptional repressor, and to an intronic site of the Il10 gene, NFATc1 suppresses IL-10 expression that dampens the production of tumour necrosis factor-α and IL-17 by T cells. These data indicate a close link between NFATc1 and IL-10 expression in B cells and suggest NFATc1 and, in particular, its inducible short isoform, NFATc1/αA, as a potential target to treat human psoriasis.

Alternatively activated (M2) macrophages promote wound healing but weaken antimicrobial defenses. The mechanisms that enforce macrophage divergence and dictate the phenotypic and metabolic characteristics of M2 macrophages remain elusive. We show that alternative activation with interleukin (IL)-4 induces expression of metallothionein 3 (MT3) that regulates macrophage polarization and function. MT3 was requisite for metabolic reprograming in IL-4-stimulated macrophages or M(IL-4) macrophages to promote mitochondrial respiration and suppress glycolysis. MT3 fostered an M(IL-4) phenotype, suppressed hypoxia inducible factor (HIF)1α activation, and thwarted the emergence of a proinflammatory M1 program in macrophages. MT3 deficiency augmented macrophage plasticity, resulting in enhanced interferon γ (IFNγ) responsiveness and a dampened M(IL-4) phenotype. Thus, MT3 programs the phenotype and metabolic fate of M(IL-4) macrophages.

Regulatory B cells (Bregs) are unique subpopulations of B cells with immune-regulating or immune-suppressing properties and play a role in peripheral tolerance. Due to the current limitations of human Breg studies among periodontal diseases, in the present study, we tried to analyze the change in circulating Bregs, pro-inflammatory, and anti-inflammatory cytokines in patients with periodontitis. Peripheral blood from 55 patients with stage 2 periodontitis and 20 healthy controls was analyzed using flow cytometry to evaluate the frequency of CD19⁺CD24⁺CD38⁺ Breg cells. ELISA was used to assess the serum levels of the pro-inflammatory cytokines, including interleukins (IL)-1β, IL-6, TNF-α, and anti-inflammatory cytokines including IL-10, IL-35, and TGF-β. Increased proportions of Breg cells were observed in patients with stage 2 periodontitis compared to controls. Serum levels of cytokines were significantly higher in patients with periodontitis compared to controls. A significant positive correlation was observed between the frequencies of Breg cells and IL35 levels, IL10 levels, and TGF-β. In conclusion, our results suggest that the increase in peripheral Breg cells and serum cytokine levels among periodontitis patients seems to be closely associated with disease progression, a possible link between periodontitis, and systemic inflammatory process.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an emerging coronavirus causing respiratory disease commonly known as COVID-19. This novel coronavirus transmits from human to human and has caused profound morbidity and mortality worldwide leading to the ongoing pandemic. Moreover, disease severity differs considerably from individual to individual. Investigating the virology of COVID-19 and immunological pathways underlying its clinical manifestations will enable the identification and design of effective vaccines and potential therapies. In this review, we explore COVID-19 virology, the contribution of the immune system (innate and adaptive) during infection and control of the virus. Finally, we highlight vaccine development and implications of immune system modulation for potential therapeutic interventions to design better therapeutic strategies to guide future cure.