Nuclear architecture of resting and LPS-stimulated porcine neutrophils by 3D FISH

Abstract

Neutrophils are essential components of the innate immune system due to their ability to kill and phagocytose invading microbes. They possess a lobulated nucleus and are capable of extensive and complex changes in response to bacterial stimulation. The aim of our study was to investigate whether the 3D nuclear organization of porcine neutrophils was modified upon stimulation. The organization of centromeres, telomeres, and chromosome territories (chromosomes 2, 3, 7, 8, 12, 13, and 17) was studied on structurally preserved nuclei using 3D fluorescence in situ hybridization, confocal microscopy, and image analysis. By differential labeling of centromeres of acrocentric and metacentric/submetacentric chromosomes, we showed that centromeres associated to form chromocenters but did so preferentially between chromosomes with the same morphology. Upon activation, some of these chromocenters dispersed. Telomeres were also found to form clusters, but their number remained unchanged in lipopolysaccharide-stimulated neutrophils. The analysis of the position of chromocenters and telomere clusters showed a more internal location of the latter compared to the former. The analysis of chromosome territories revealed that homologs were distributed randomly among lobes whatever the cell's status. The volume of these territories was not proportional to chromosome length, and some chromosomes (chr 3, 12, 13, and 17) were more prone to decondensation when neutrophils were stimulated. Thus, our study demonstrated that activation of neutrophils resulted in several modifications of their nuclear architecture: a decrease in the number of non-acrocentric chromocenters and the decondensation of several chromosomes.

Nuclear organization during in vitro differentiation of porcine mesenchymal stem cells (MSCs) into adipocytes

“…Telomere clustering was detected in both undifferentiated and terminally differentiated cells. It seems that this is a characteristic feature of interphase nuclei arrangements, since it was observed in many cell types, including lymphocytes, neutrophils, and cancer cells (Chuang et al 2004;Weierich et al 2003;Yerle-Bouissou et al 2009). Since mammalian HP1α localizes with pericentromeric heterochromatin in the interphase, we also analysed the distribution of chromocenters.…”

Nuclear Segmentation, Condensation and Bilateral Symmetry in Polymorphonuclear Leukocytes Reflect Genomic Order and Favor Immunologic Function

“…Perhaps this failure was due to the small number of cases and the very low proportion of them with cells with bilateral symmetry, or these specimens were from cases with immunologic deficiency. Similarly, Yerle-Bouissoin et al [49] applied 3-D FISH on porcine neutrophils. However, they focused on the effect of lipopolysaccharide stimulation and did not examine the bilaterally symmetric nuclei.…”

Transcriptomic and nuclear architecture of immune cells after LPS activation

“…However, data available on the spatial organization of the genome concern principally the lymphocytes while little information is available for phagocytes, which also play a key role in this process. Some studies have analysed the 3D nuclear organization of chromosome territories in murine macrophages (Mayer et al 2005;Hepperger et al 2008) and in human (Hepperger et al 2009) and porcine (Yerle-Bouissou et al 2009) neutrophils. The relation between nuclear position and gene activity status has been investigated in human neutrophils (Bártová et al 2002), and chicken (Stadler et al 2004) and murine (Hepperger et al 2008) macrophages but mainly in the context of cell differentiation.…”

“…Similarly, two batches (control and LPS activated) were prepared for neutrophils as described previously (Yerle-Bouissou et al 2009). …”