Refine
Language
- English (3)
Has Fulltext
- yes (3)
Keywords
- immunology (1)
- killing efficiency (1)
- natural killer cells (1)
- verbena officinalis (1)
Scientific Unit
- Dynamic Biomaterials (1)
- Fellow (1)
Natural killer (NK) cells play key roles in eliminating pathogen-infected cells. Verbena officinalis (V. officinalis) has been used as a medical plant in traditional and modern medicine for its anti-tumor and anti-inflammatory activities, but its effects on immune responses remain largely elusive. This study aimed to investigate the potential of V. officinalis extract (VO extract) to regulate inflammation and NK cell functions. We examined the effects of VO extract on lung injury in a mouse model of influenza virus infection. We also investigated the impact of five bioactive components of VO extract on NK killing functions using primary human NK cells. Our results showed that oral administration of VO extract reduced lung injury, promoted the maturation and activation of NK cells in the lung, and decreased the levels of inflammatory cytokines (IL-6, TNF-α and IL-1β) in the serum. Among five bioactive components of VO extract, Verbenalin significantly enhanced NK killing efficiency in vitro, as determined by real-time killing assays based on plate-reader or high-content live-cell imaging in 3D using primary human NK cells. Further investigation showed that treatment of Verbenalin accelerated the killing process by reducing the contact time of NK cells with their target cells without affecting NK cell proliferation, expression of cytotoxic proteins, or lytic granule degranulation. Together, our findings suggest that VO extract has a satisfactory anti-inflammatory effect against viral infection in vivo, and regulates the activation, maturation, and killing functions of NK cells. Verbenalin from V. officinalis enhances NK killing efficiency, suggesting its potential as a promising therapeutic to fight viral infection.
Background Natural killer (NK) cells play a key role in eliminating tumorigenic and pathogen-infected cells. Verbena officinalis (V. officinalis) has been used as a medical plant in traditional and modern medicine, exhibiting anti-tumor and anti-inflammation activity.Purpose The impact of bioactive constituents of V. officinalis on immune responses still remains largely elusive. In this work we investigated the potential targets of V. officinalis and focused on killing efficiency and related functions of NK cells regulated by bioactive constituents of V. officinalis.Study design/methods We used primary human NK cells from peripheral blood mononuclear cells. Potential regulatory roles of selected compounds were analyzed by network pharmacology approaches. Killing efficiency was determined with real-time killing assay and live-cell imaging in 3D. Proliferation was examined by CFSE staining. Expression of cytotoxic proteins was analyzed using flow cytometry. Lytic granule release was quantified by CD107a degranulation assay. Contact time required for killing and determination of serial killers were analyzed using live cell imaging results. Results: Using network pharmacology approaches, we analyzed potential regulatory roles of five compounds (Acteoside, Apigenin, Kaempferol, Verbenalin and Hastatoside) from V. officinalis on immune cell functions and revealed NK cells as a major target. The effect of these compounds on NK killing efficiency was examined with real-time killing assay, and Verbenalin enhanced NK killing efficiency significantly. Further investigation showed that Verbenalin did not affect proliferation, expression of cytotoxic proteins, or lytic granule degranulation, but rather reduced contact time required for killing therefore enhancing total killing events per NK cell, suggestively via inhibition of inhibitory receptors as determined by docking assay.Conclusions Our findings reveal the underlying mechanisms how V. officinalis regulates functions of immune cells, especially NK cells, suggesting Verbenalin from V. officinalis as a promising therapeutic reagent to fight cancer and infection.Competing Interest StatementThe authors have declared no competing interest.
Biological materials achieve directional reinforcement with oriented assemblies of anisotropic building blocks. One such example is the nanocomposite structure of keratinized epithelium on the toe pad of tree frogs, in which hexagonal arrays of (soft) epithelial cells are crossed by densely packed and oriented (hard) keratin nanofibrils. Here, a method is established to fabricate arrays of tree-frog-inspired composite micropatterns composed of polydimethylsiloxane (PDMS) micropillars embedded with polystyrene (PS) nanopillars. Adhesive and frictional studies of these synthetic materials reveal a benefit of the hierarchical and anisotropic design for both adhesion and friction, in particular, at high matrix–fiber interfacial strengths. The presence of PS nanopillars alters the stress distribution at the contact interface of micropillars and therefore enhances the adhesion and friction of the composite micropattern. The results suggest a design principle for bioinspired structural adhesives, especially for wet environments.
