Transcriptome Profiling Reveals CD73 and Age-Driven Changes in Neutrophil Responses against Streptococcus pneumoniae

Abstract

Neutrophils are required for host resistance against Streptococcus pneumoniae but their function declines with age. We previously found that CD73, an enzyme required for antimicrobial activity, is down-regulated in neutrophils from aged mice. This study explored transcriptional changes in neutrophils induced by S. pneumoniae to identify pathways controlled by CD73 and dysregulated with age. Pure bone marrow-derived neutrophils isolated from wild type (WT) young, old, and CD73KO young mice were mock-challenged or infected with S. pneumoniae ex vivo . RNA sequencing was performed to identify differentially expressed genes (DEGs). We found that infection triggered distinct global transcriptional changes across hosts, that were strongest in CD73KO neutrophils. Surprisingly, there were more down-regulated than up-regulated genes in all groups upon infection. Down-regulated DEGs indicated a dampening of immune responses in old and CD73KO hosts. Further analysis revealed that CD73KO neutrophils expressed higher numbers of long non-coding RNAs (lncRNAs) compared to WT controls. Predicted network analysis indicated that CD73KO specific lncRNAs control several signaling pathways. We found that genes in the JNK-MAPK-pathway were up-regulated upon infection in CD73KO and WT old but not in young mice. This corresponded to functional differences, as phosphorylation of the downstream AP-1 transcription factor component c-Jun was significantly higher in infected CD73KO and old mice neutrophils. Importantly, inhibiting JNK/AP-1 rescued the ability of these neutrophils to kill S. pneumoniae . Altogether, our findings revealed that the ability of neutrophils to modify their gene expression to better adapt to bacterial infection is in part regulated by CD73 and declines with age.

Mitochondrial ROS production by neutrophils is required for host antimicrobial function againstStreptococcus pneumoniaeand is controlled by A2B adenosine receptor signaling

“…We previously found that scavenging/ detoxifying ROS completely abrogates the ability of PMNs to kill S. pneumoniae [12]. To determine if mitochondrial ROS were important for the antimicrobial function of PMNs, we treated PMNs with MitoTEMPO and measured the ability of PMNs to kill S. pneumoniae TIGR4 strain using an established opsonophagocytic (OPH) killing assay [2, 12, 32–34, 49]. We found that treatment with MitoTEMPO lead to a complete abrogation of bacterial killing by PMNs (Fig.…”

“…Pathways that regulate MitROS production by PMNs have not been explored. Extracellular adenosine (EAD) is a key regulator of PMN responses during pneumococcal infection [2, 12, 32–34]. EAD is produced in the extracellular environment as a breakdown product of ATP released from damage cells where two extracellular enzymes CD39 and CD73 sequentially de-phosphorylate ATP to EAD [35].…”

Pseudomonas aeruginosa Detection Using Conventional PCR and Quantitative Real-Time PCR Based on Species-Specific Novel Gene Targets Identified by Pangenome Analysis

“…However, traditional detection methods for P. aeruginosa may cause false positives or missed positives and are considerably time-consuming. Automated systems such as VITEK 2, which walkway system that works on the principle of photometry, promise shorter turnaround times to detect P. aeruginosa , but these systems have a low rate of accuracy in the identification ( Torrecillas et al, 2020 ; Bhalla et al, 2021 ; Miranda-Ulloa et al, 2021 ; Pintado-Berninches et al, 2021 ; Viedma et al, 2021 ). Immunological approaches use the highly specific binding between antigens and antibodies and facilitate qualitative or quantitative detection that is based on specific reactions resulted from antigen antibody binding ( Rainbow et al, 2020 ).…”

“…Immunological approaches use the highly specific binding between antigens and antibodies and facilitate qualitative or quantitative detection that is based on specific reactions resulted from antigen antibody binding ( Rainbow et al, 2020 ). High-sensitivity detection has been reached by modern immunoassay approaches, but their relatively tedious procedures have limited further development ( Bhalla et al, 2021 ; Miranda-Ulloa et al, 2021 ; Viedma et al, 2021 ). In addition, greatest drawback of immunofluorescence methods is a low signal-to-noise ratio, which may lower its detection specificity ( Pintado-Berninches et al, 2021 ).…”

Cellular Senescence in Immunity against Infections

“…Conversely, young patients versus elderly patients had more alveolar macrophages [ 146 ]. The activation of c-Jun N-terminal kinase/activator protein-1 (JNK/AP-1), one of the MAPK signaling pathways, was significantly upregulated in response to S. pneumoniae infection in PMNs from old mice compared to young controls, and its pharmacological inhibition reversed the defect in pneumococcal killing by PMNs, indicating that this pathway can potentially be targeted to reverse the age-related dysregulation of PMN responses [ 147 ]. Lower IL-10 production was associated with higher levels of chemokine ligands CXCL9, CXCL12, CCL3, CCL4, CCL5, CCL11 and CCL17 in infected old mice, suggesting a defect in anti-inflammatory cytokine production by immune cells in the lung [ 145 ].…”