The Impact of Rubella Virus Infection on a Secondary Inflammatory Response in Polarized Human Macrophages

Macrophages (MΦ) are known to exhibit distinct responses to viral and bacterial infection, but how they react when exposed to the pathogens in succession is less well understood. Accordingly, we determined the effect of a rubella virus (RV)-induced infection followed by an LPS-induced challenge on cytokine production, signal transduction and metabolic pathways in human GM (M1-like)- and M (M2-like)-MΦ. We found that infection of both subsets with RV resulted in a low TNF-α and a high interferon (IFN, type I and type III) release whereby M-MΦ produced far more IFNs than GM-MΦ. Thus, TNF-α production in contrast to IFN production is not a dominant feature of RV infection in these cells. Upon addition of LPS to RV-infected MΦ compared to the addition of LPS to the uninfected cells the TNF-α response only slightly increased, whereas the IFN-response of both subtypes was greatly enhanced. The subset specific cytokine expression pattern remained unchanged under these assay conditions. The priming effect of RV was also observed when replacing RV by IFN-β one putative priming stimulus induced by RV. Small amounts of IFN-β were sufficient for phosphorylation of Stat1 and to induce IFN-production in response to LPS. Analysis of signal transduction pathways activated by successive exposure of MΦ to RV and LPS revealed an increased phosphorylation of NFκB (M-MΦ), but different to uninfected MΦ a reduced phosphorylation of ERK1/2 (both subtypes). Furthermore, metabolic pathways were affected; the LPS-induced increase in glycolysis was dampened in both subtypes after RV infection. In conclusion, we show that RV infection and exogenously added IFN-β can prime MΦ to produce high amounts of IFNs in response to LPS and that changes in glycolysis and signal transduction are associated with the priming effect. These findings will help to understand to what extent MΦ defense to viral infection is modulated by a following exposure to a bacterial infection.

Priming Effect of Exogenous ABA on Heat Stress Tolerance in Rice Seedlings is Associated with the Upregulation of Antioxidative Defense Capability and Heat Shock-Related Genes

Heat stress is a major restrictive factor that suppresses rice production. In this study, we investigated the potential priming effect of exogenous abscisic acid (ABA) on heat tolerance in rice seedlings. Seedlings were pretreated with 10 μM ABA by root drenching for 24 h and then subjected to heat stress conditions of 40 °C day/35 °C night. ABA pretreatment significantly decreased leaf withering by 2.5– 28.5% and chlorophyll loss by 12.8–35.1% induced by heat stress in rice seedlings. ABA application also mitigated cell injury, as shown by lower malondialdehyde (MDA) content, membrane injury and expression of cell death-related genes OsKOD1 , OsCP1 and OsNAC4 , while expression of OsBI1 , a cell death-suppressor gene, was upregulated by ABA pretreatment. Moreover, ABA pretreatment improved antioxidant defense capacity, as shown by an obvious upregulation of ROS-scavenging genes and a decrease in ROS content (O 2 – and H 2 O 2 ) and downregulation of the OsRbohs gene. The application of fluridone, an ABA biosynthesis inhibitor, increased membrane injury and the accumulation of ROS under heat stress. Exogenous potent antioxidants (proanthocyanidins, PC) significantly alleviated leaf withering by decreasing ROS overaccumulation and membrane injury induced by heat stress. In addition, ABA pretreatment significantly superinduced the expression of ABA-responsive genes SalT and OsWsi18 , the ABA biosynthesis genes OsNCED3 and OsNCED4 , and the heat shock-related genes OsHSP23.7 , OsHSP17.7 , OsHSF7 and OsHsfA2a . Taken together, these results suggest that exogenous ABA has a potential priming effect for enhancing heat stress tolerance of rice seedlings mainly by improving antioxidant defense capacity and heat shock-related genes.

SPAML: Semantic Priming Across Many Languages

Semantic priming has been studied for nearly 50 years across various experimental manipulations and theoretical frameworks. These studies provide evidence of cognitive underpinnings of the structure and organization of semantic representation in both healthy and clinical populations. In this registered report, we propose to create a large database of semantic priming values, alleviating the sample size and limited language issues with previous studies in this area. Consequently, this database will include semantic priming data across multiple languages using an adaptive sampling procedure. This study will test the size of semantic priming effect and its variability across languages. Results will support semantic priming when reduced response latencies are found for related word-pair conditions in comparison to unrelated word-pair conditions. Differences in semantic priming across languages will be supported when priming effect confidence intervals do not overlap.