Caspase-11 deficiency attenuates neutrophil recruitment into the atherosclerotic lesion in apolipoprotein E-deficient mice.

Caspase-11 is an inflammatory caspase that triggers an inflammatory response by regulating non-canonical NLRP3 inflammasome activation. Although the deficiency of both caspase-11 and caspase-1, another inflammatory caspase that functions as an executor of the inflammasome, prevents the development of atherosclerosis, the effect of caspase-11 deficiency alone on the development of atherosclerosis has not been fully evaluated. In the present study, we found that caspase-11 deficiency prevented the formation of the necrotic core, whereas it did not affect the development of atherosclerosis in Apoe-deficient mice. Notably, the infiltration of neutrophils into atherosclerotic lesions was attenuated by caspase-11 deficiency. RNA-seq analysis of stage-dependent expression of atherosclerotic lesions revealed that both upregulations of caspase-11 and neutrophil migration are common features of advanced atherosclerotic lesions. Furthermore, similar expression profiles were observed in unstable human plaque. These data suggest that caspase-11 regulates neutrophil recruitment and plaque destabilization in advanced atherosclerotic lesions.

Molecular crowding improves bead-based padlock rolling circle amplification.

Bead-based padlock rolling circle amplification (RCA), an ultrasensitive and accurate DNA detection technique, was conducted in a molecular crowding environment created by poly(ethylene glycol) (PEG). The number of RCA products generated increased and exhibited a bell-shaped dependence on PEG concentration. Experiments using magnetic beads suggested that facilitation of DNA ligation and hybridization is the main reason for the observed increase. Selectivity of the technique was retained in the presence of PEG. This technique is simple and can be utilized to detect target DNA with high accuracy and sensitivity in a variety of areas such as medical diagnosis and food analysis.

A Myb enhancer-guided analysis of basophil and mast cell differentiation.

The transcription factor MYB is a crucial regulator of hematopoietic stem and progenitor cells. However, the nature of lineage-specific enhancer usage of the Myb gene is largely unknown. We identify the Myb -68 enhancer, a regulatory element which marks basophils and mast cells. Using the Myb -68 enhancer activity, we show a population of granulocyte-macrophage progenitors with higher potential to differentiate into basophils and mast cells. Single cell RNA-seq demonstrates the differentiation trajectory is continuous from progenitors to mature basophils in vivo, characterizes bone marrow cells with a gene signature of mast cells, and identifies LILRB4 as a surface marker of basophil maturation. Together, our study leads to a better understanding of how MYB expression is regulated in a lineage-associated manner, and also shows how a combination of lineage-related reporter mice and single-cell transcriptomics can overcome the rarity of target cells and enhance our understanding of gene expression programs that control cell differentiation in vivo.