Discovery, Genomic Analysis, and Functional Role of the Erythrocyte RNAs

MicroRNAs as Quality Assessment Tool in Stored Packed Red Blood Cell in Blood Banks

Micro-ribonucleic acids are control gene expression in cells. They represent the changed cellular states that occur can be employed as biomarkers. Red blood cells alter biochemically and morphologically while they are being stored, which could be detrimental to transfusion. The effect of storage on the erythrocyte transcriptome is not mostly investigated. Because adult erythrocytes lack a nucleus, it has long been assumed that they lack deoxyribonucleic acid and ribonucleic acid. On the other hand, erythrocytes contain a diverse range of ribonucleic acids, of which micro-ribonucleic acids are key component. Changes in this micro-ribonucleic acid protect cells from death and adenine triphosphate depletion, and they are linked to specific storage lesions. As a result, changes in micro-ribonucleic acid in stored erythrocytes may be used as a marker to assess the quality and safety of stored erythrocytes. Therefore, this review ams to review the role of microRNA in stored packed red blood cells as quality indicator. Google Scholar, PubMed, Scopus, and Z-libraries are used for searching articles and books. The article included in this paper was written in the English language and had the full article. During long storage of RBCs, miR-16-2-3p, miR-1260a, miR-1260b, miR-4443, miR-4695-3p, miR-5100, let-7b, miR-16, miRNA-1246, MiR-31-5p, miR-203a, miR-654-3p, miR-769-3p, miR-4454, miR-451a and miR-125b- 5p are up regulated. However, miR-96, miR-150, miR-196a, miR-197, miR-381 and miR-1245a are down regulated after long storage of RBCs. The changes of this microRNAs are linked to red blood cell lesions. Therefore, micro-ribonucleic acids are the potential quality indicator in stored packed red blood cells in the blood bank. Particularly, micro-ribonucleic acid-96 is the most suitable biomarker for monitoring red blood cell quality in stored packed red blood units.

Expression and Bioinformatics Analysis of Key miRNAs in Stored Red Blood Cells

Introduction

Erythrocyte transfusion is the most common therapeutic procedure in hospitalized patients. Adding standard preservatives to red blood cells allows them to be stored for up to 42 days. However, whether storage has an effect on the erythrocyte transcriptome has not been well-studied.

Objective

This study was designed to explore the change of key risk microRNA (miRNAs) in stored erythrocytes.

Methods

We reanalyzed differentially expressed genes in the gene expression dataset GSE114990 and predicted their target genes, followed by experimental Gene Ontology (GO) analysis and (Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. Furthermore, the PPI network of target genes was constructed by the STRING database, and the module analysis was carried out.

Results

We found two differential miRNAs, which were hsa-miR-1245a and hsa-miR-381. Enrichment analysis of GO and KEGG pathways confirmed that these target genes were significantly enriched in organ and system development, anchoring junction, transcription factor binding, and pathways of cancer.

Conclusion

The results suggest that the miRNAs hsa-miR-381 and hsa-miR-1245a may serve as biomarkers for storage products of erythrocytes.

Single Cell RNA-Seq Analysis of Human Red Cells

Human red blood cells (RBCs), or erythrocytes, are the most abundant blood cells responsible for gas exchange. RBC diseases affect hundreds of millions of people and impose enormous financial and personal burdens. One well-recognized, but poorly understood feature of RBC populations within the same individual are their phenotypic heterogeneity. The granular characterization of phenotypic RBC variation in normative and disease states may allow us to identify the genetic determinants of red cell diseases and reveal novel therapeutic approaches for their treatment. Previously, we discovered diverse RNA transcripts in RBCs that has allowed us to dissect the phenotypic heterogeneity and malaria resistance of sickle red cells. However, these analyses failed to capture the heterogeneity found in RBC sub-populations. To overcome this limitation, we have performed single cell RNA-Seq to analyze the transcriptional heterogeneity of RBCs from three adult healthy donors which have been stored in the blood bank conditions and assayed at day 1 and day 15. The expression pattern clearly separated RBCs into seven distinct clusters that include one RBC cluster that expresses HBG2 and a small population of RBCs that express fetal hemoglobin (HbF) that we annotated as F cells. Almost all HBG2-expessing cells also express HBB, suggesting bi-allelic expression in single RBC from the HBG2/HBB loci, and we annotated another cluster as reticulocytes based on canonical gene expression. Additional RBC clusters were also annotated based on the enriched expression of NIX, ACVR2B and HEMGN, previously shown to be involved in erythropoiesis. Finally, we found the storage of RBC was associated with an increase in the ACVR2B and F-cell clusters. Collectively, these data indicate the power of single RBC RNA-Seq to capture and discover known and unexpected heterogeneity of RBC population.

Weaning differentially affects the maturation of piglet peripheral blood and jejunal Peyer's patches

The study aimed to assess how the post-weaning condition changes piglet peripheral blood (PB) and jejunal Peyer's patches (JPPs) as compared to the suckling period, and how these changes are associated with intestinal microbiota evolution. Sixteen pigs were slaughtered and sampled for PB, JPPs and jejunal content (JC) at weaning (26 days) or at 12 days fed on a pre-starter diet. The PB and JPP transcriptomes were analysed using mRNA-seq. The Gene Set Enrichment Analysis was used to demonstrate enriched gene clusters, depending on sampling time. Jejunal microbiota was profiled using 16S rRNA gene sequencing. Post-weaning JPPs were enriched for processes related to the activation of IFN-γ and major histocompatibility complex (MHC) class I antigen processing which clustered with the reduced abundance of the Weisella genus and Faecalibacterium prausnitzii in JC. The post-weaning microbiome differed from that seen in just-weaned pigs. For just-weaned PB, the enrichment of genes related to hemoglobin and the iron metabolism indicated the greater presence of reticulocytes and immature erythrocytes. The JPP genes involved in the I MHC and IFN-γ activations were markers of the post-weaning phase. Several genes attributable to reticulocyte and erythrocyte maturation could be interesting for testing the iron nutrition of piglets.

Classical and intermediate monocytes scavenge non-transferrin-bound iron and damaged erythrocytes

Myelomonocytic cells are critically involved in iron turnover as aged RBC recyclers. Human monocytes are divided in 3 subpopulations of classical, intermediate, and nonclassical cells, differing in inflammatory and migratory phenotype. Their functions in iron homeostasis are, however, unclear. Here, we asked whether the functional diversity of monocyte subsets translates into differences in handling physiological and pathological iron species. By microarray data analysis and flow cytometry we identified a set of iron-related genes and proteins upregulated in classical and, in part, intermediate monocytes. These included the iron exporter ferroportin (FPN1), ferritin, transferrin receptor, putative transporters of non-transferrin-bound iron (NTBI), and receptors for damaged erythrocytes. Consequently, classical monocytes displayed superior scavenging capabilities of potentially toxic NTBI, which were augmented by blocking iron export via hepcidin. The same subset and, to a lesser extent, the intermediate population, efficiently cleared damaged erythrocytes in vitro and mediated erythrophagocytosis in vivo in healthy volunteers and patients having received blood transfusions. To summarize, our data underline the physiologically important function of the classical and intermediate subset in clearing NTBI and damaged RBCs. As such, these cells may play a nonnegligible role in iron homeostasis and limit iron toxicity in iron overload conditions.

Human classical and intermediate monocytes mediate clearance of non-transferrin-bound iron and erythrophagocytosis.

Trans-kingdom small RNA transfer during host-pathogen interactions: The case of P. falciparum and erythrocytes

This review focuses on the role of trans-kingdom movement of small RNA (sRNA) molecules between parasites, particularly Plasmodium falciparum, and their respective host cells. While the intercellular transfer of sRNAs within organisms is well recognized, recent studies illustrate many examples of trans-kingdom sRNA exchange within the context of host-parasite interactions. These interactions are predominantly found in the transfer of host sRNAs between erythrocytes and the invading P. falciparum, as well as other host cell types. In addition, parasite-encoded sRNAs can also be transferred to host cells to evade the immune system. The transport of these parasite sRNAs in the body fluids of the host may also offer means to detect and monitor the parasite infection. These isolated examples may only represent the tip of the iceberg in which the transfer of sRNA between host and parasites is a critical aspect of host-pathogen interactions. In addition, the levels of these sRNAs and their speed of transfer may vary dramatically under different contexts to push the biologic equilibrium toward the benefit of hosts vs. parasites. Therefore, these sRNA transfers may offer potential strategies to detect, prevent or treat parasite infections. Here, we review a brief history of the discovery of host erythrocyte sRNAs, their transfers and interactions in the context of P. falciparum infection. We also provide examples and discuss the functional significance of the reciprocal transfer of parasite-encoded sRNAs into hosts. These understandings of sRNA exchanges are put in the context of their implications for parasite pathogenesis, host defenses and the evolution of host polymorphisms driven by host interactions with these parasites.