Biology subjects

Anand, S. K.

Publications and source records attributed to Anand, S. K..

2 recordsLinked to original sources

bioRxiv2024

CD14 Blockade Does Not Improve Outcomes of Deep Vein Thrombosis Following Inferior Vena Cava Stenosis in Mice

BackgroundNeutrophil-mediated persistent inflammation and neutrophil extracellular trap formation (NETosis) promote deep vein thrombosis (DVT). CD14, a co-receptor for toll-like receptor 4 (TLR4), is actively synthesized by neutrophils, and the CD14/TLR4 signaling pathway has been implicated in proinflammatory cytokine overproduction and several aspects of thromboinflammation. The role of CD14 in the pathogenesis of DVT remains unclear. ObjectiveTo determine whether CD14 blockade improves DVT outcomes. MethodsBulk RNA sequencing and proteomic analyses were performed using isolated neutrophils following inferior vena cava (IVC) stenosis in mice. DVT outcomes (IVC thrombus weight and length, thrombosis incidence, neutrophil recruitment, and NETosis) were evaluated following IVC stenosis in mice treated with a specific anti-CD14 antibody, 4C1, or control antibody. ResultsMice with IVC stenosis exhibited increased plasma levels of granulocyte colony-stimulating factor (G-CSF) along with a higher neutrophil-to-lymphocyte ratio and increased plasma levels of cell-free DNA, elastase, and myeloperoxidase. Quantitative measurement of total neutrophil mRNA and protein expression revealed distinct profiles in mice with IVC stenosis compared to mice with sham surgery. Neutrophils of mice with IVC stenosis exhibited increased inflammatory transcriptional and proteomic responses, along with increased expression of CD14. Treatment with a specific anti-CD14 antibody, 4C1, did not result in any significant changes in the IVC thrombus weight, thrombosis incidence, or neutrophil recruitment to the thrombus. ConclusionThe results of the current study are important for understanding the role of CD14 in the regulation of DVT and suggest that CD14 lacks an essential role in the pathogenesis of DVT following IVC stenosis.

pathology↗

bioRxiv2023

SH2 domain protein E (SHE) and ABL signaling regulate blood vessel size

Blood vessels in different vascular beds vary in lumen diameter, which is essential for their function and fluid flow along the vascular network. Molecular mechanisms involved in the formation of a vascular lumen of appropriate size, or tubulogenesis, are still only partially understood. Src homology 2 domain containing E (She) protein was previously identified in a screen for proteins that interact with Abelson (Abl)-kinase. However, its biological role has remained unknown. Here we demonstrate that She and Abl signaling regulate vascular lumen size in zebrafish embryos and human endothelial cell culture. Zebrafish she mutants displayed increased endothelial cell number and enlarged lumen size of the dorsal aorta (DA) and defects in blood flow. Vascular endothelial specific overexpression of she resulted in a reduced diameter of the DA lumen, which correlated with the reduced arterial cell number and lower endothelial cell proliferation. Chemical inhibition of Abl signaling in zebrafish embryos caused a similar reduction in the DA diameter and alleviated the she mutant phenotype, suggesting that She acts as a negative regulator of Abl signaling. Enlargement of the DA lumen in she mutants correlated with an increased endothelial expression of claudin 5a and 5b (cldn5a / cldn5b), which encode proteins enriched in tight junctions. Inhibition of cldn5a expression partially rescued the enlarged DA in she mutants, suggesting that She regulates DA lumen size, in part, by promoting cldn5a expression. SHE knockdown in human endothelial umbilical vein cells resulted in a similar increase in the diameter of vascular tubes, and also increased phosphorylation of a known ABL downstream effector CRKL. These results argue that SHE functions as an evolutionarily conserved inhibitor of ABL signaling and regulates lumen size during vascular tubulogenesis.

developmental biology↗