Mouse mast cells (MCs) express a large number of serine proteases including tryptases, mouse mast cell protease (mMCP)-6 and -7; chymases, mMCP-1, -2, and -4; and an elastase, mMCP-5; along with ...carboxypeptidase-A3 (CPA3). In helminth-infected mouse intestine, distinct protease phenotypes are observed for connective tissue MCs (CTMCs) (mMCP-4+–7+, and CPA3+) and mucosal MCs (MMCs) (mMCP-1+ and 2+). To determine whether the protease phenotype was regulated by the tissue, we compared the phenotype of constitutive CTMCs and induced MMCs in trachea and large airways in antigen-sensitized unchallenged and challenged mice to MCs in skin and helminthic-infected intestine. We found that in the trachea, unlike in skin and intestine, CTMCs and MMCs both express all six serine proteases and CPA3 (mMCP-1+, -2+, 4+–7+, CPA3+). This phenotype also holds for the lung CTMCs in the proximal bronchi, whereas the induced MMCs express only four proteases, mMCP-1, -2, -6, and -7. Thus, the T-cell–dependent induction of MMCs in trachea, large bronchi, and small intestine provides numbers but does not determine the protease phenotype. Furthermore, the CTMCs, which are constitutive, also show striking differences at these tissue sites, supporting the view that the differences in expression are tissue directed and not dependent on inflammation.
Objective
Group 3 innate lymphoid cells (ILC3s) play a pivotal role in barrier tissues such as the gut and the skin, two important sites of disease in spondyloarthritis (SpA). This study was ...undertaken to investigate whether normal or injured human enthesis, a key target tissue in early SpA, harbors ILC3s in entheseal soft tissue and adjacent perientheseal bone.
Methods
Interspinous ligament and spinous process bone from donors with no systemic inflammatory disease were collected, enzymatically digested, and immunophenotyped. The immunologic profile of entheseal cells was examined, and the transcriptional profile of sorted ILC3s was compared to that of ILC3s isolated from SpA synovial fluid (SF). To assess the ability of entheseal tissue to produce interleukin‐17 (IL‐17) and IL‐22, entheseal digests were stimulated with IL‐23 and IL‐1β. Osteoarthritic and ruptured Achilles tendon tissue was examined histologically.
Results
The proportion of ILCs in human entheseal soft tissue was higher than that in peripheral blood (P = 0.008); entheseal soft tissue and perientheseal bone both had a higher proportion of NKp44+ ILC3s (P = 0.001 and P = 0.043, respectively). Studies of retinoic acid receptor–related orphan nuclear receptor γt (RORγt), STAT3, and IL‐23 receptor transcript expression validated the entheseal ILC3 phenotype. Cytokine transcript expression was similar in ILC3s isolated from enthesis and from SpA SF. Stimulation of normal entheseal digests with IL‐23/IL‐1β led to up‐regulation of IL‐17A transcript, and histologic examination of injured/damaged entheses revealed the presence of RORγt‐expressing cells.
Conclusion
This work shows that human enthesis harbors a resident population of ILC3s, with the potential to participate in the pathogenesis of SpA.
Immune cells and stromal cells regulate wound healing and regeneration through complex activation patterns with spatiotemporal variation. The scarless regeneration of Spiny mice (Acomys species) is ...no exception; differential activation of immune and stromal cell populations seems to play a role in its remarkable regenerative capacity. To elucidate the role and interplay of Acomys immune cells in mammalian regeneration, we sought to create Acomys-Mus chimeras by transplanting bone marrow (BM) from Acomys into NOD Scid Gamma (NSG), a severely immunodeficient mouse line often used in creating humanized mice. Here, we report that Acomys BM cells fail to reconstitute and differentiate when transferred to irradiated NSG adults and neonates. In addition, we did not detect the presence of donor cells nor observe the onset of Graft versus Host Disease (GvHD)-like pathology, even after transplanting Acomys splenocytes in Acomys-Mus chimeras suggesting early graft failure. Overall, these results demonstrate the adoptive transfer of Acomys BM alone is not sufficient to establish Acomys hematopoietic system in NSG mouse.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Calcific aortic valve disease (CAVD) is the most common heart valve disorder, yet its mechanism remains poorly understood. Valve interstitial cells (VICs) are the prevalent cells in aortic valve and ...their osteogenic differentiation may be responsible for calcific nodule formation in CAVD pathogenesis. Emerging evidence shows microRNA (miRNA, or miR) can function as important regulators of many pathological processes, including osteogenic differentiation. Here, we aimed to explore the function of miR-449c-5p in CAVD pathogenesis. In this study, we demonstrated the role of miR-449c-5p in VICs osteogenesis. MiRNA microarray assay and qRT-PCR results revealed miR-449c-5p was significantly down-regulated in calcified aortic valves compared with non-calcified valves. MiR-449c-5p overexpression inhibited VICs osteogenic differentiation in vitro, whereas down-regulation of miR-449c-5p enhanced the process. Target prediction analysis and dual-luciferase reporter assay confirmed Smad4 was a direct target of miR-449c-5p. Furthermore, knockdown of Smad4 inhibited VICs osteogenic differentiation, similar to the effect observed in up-regulation miR-449c-5p. In addition, animal experiments proved indirectly miR-449c-5p could alleviate aortic valve calcification. Our data suggested miR-449c-5p could function as a new inhibitory regulator of VICs osteogenic differentiation, which may act by targeting Smad4. MiR-449c-5p may be a potential therapeutic target for CAVD.
Human endothelial cells (ECs) and pericytes are of great interest for research on vascular development and disease, as well as for future therapy. This protocol describes the efficient generation of ...ECs and pericytes from human pluripotent stem cells (hPSCs) under defined conditions. Essential steps for hPSC culture, differentiation, isolation and functional characterization of ECs and pericytes are described. Substantial numbers of both cell types can be derived in only 2-3 weeks: this involves differentiation (10 d), isolation (1 d) and 4 or 10 d of expansion of ECs and pericytes, respectively. We also describe two assays for functional evaluation of hPSC-derived ECs: (i) primary vascular plexus formation upon coculture with hPSC-derived pericytes and (ii) incorporation in the vasculature of zebrafish xenografts in vivo. These assays can be used to test the quality and drug sensitivity of hPSC-derived ECs and model vascular diseases with patient-derived hPSCs.
Intestinal stromal cells are known to modulate the propagation and differentiation of intestinal stem cells
. However, the precise cellular and molecular mechanisms by which this diverse stromal cell ...population maintains tissue homeostasis and repair are poorly understood. Here we describe a subset of intestinal stromal cells, named MAP3K2-regulated intestinal stromal cells (MRISCs), and show that they are the primary cellular source of the WNT agonist R-spondin 1 following intestinal injury in mice. MRISCs, which are epigenetically and transcriptomically distinct from subsets of intestinal stromal cells that have previously been reported
, are strategically localized at the bases of colon crypts, and function to maintain LGR5
intestinal stem cells and protect against acute intestinal damage through enhanced R-spondin 1 production. Mechanistically, this MAP3K2 specific function is mediated by a previously unknown reactive oxygen species (ROS)-MAP3K2-ERK5-KLF2 axis to enhance production of R-spondin 1. Our results identify MRISCs as a key component of an intestinal stem cell niche that specifically depends on MAP3K2 to augment WNT signalling for the regeneration of damaged intestine.
Decapod iridescent virus 1 (DIV1) is a newly defined iridescent virus that infects decapod crustaceans and causes significant economic loss in aquaculture. To study the mechanisms of viral infection, ...an in vitro infection system is required. Here, we investigated the infection and replication of DIV1 in primary cultured hematopoietic tissue (HPT) cells of crayfish Cherax quadricarinatus. RT-PCR and Western blot analysis showed that DIV1 could infect the in vitro cultured cells and express viral genes. Immunofluorescent analysis of DIV1 major capsid protein indicated an infection rate of ∼23%. As the infection progressed, viral DNA copy numbers in both the cells and culture medium increased. Transmission electron microscopy analysis and animal challenging experiments demonstrated the production and release of infectious progeny virions. In summary, the primary culture of C. quadricarinatus HPT cells supports the infection and proliferation of DIV1. Thus, it can be used as an in vitro system to study the virus.
•We investigate the replication of DIV1 in primary cultured HPT cells of Cherax quadricarinatus.•The in vitro cultured HPT cells support DIV1 proliferation.•The infection rate of DIV1 in cultured HPT cells is about 23%.•We provide an in vitro cell model for the study of DIV1.
Hyalocytes are the tissue-resident innate immune cell population of the vitreous body with important functions in health and vitreoretinal disease. The purpose of this study is to gain new insights ...into the biology and function of human hyalocytes in comparison to other innate immune cells.
The present study applies fluorescence-activated cell sorting and RNA sequencing to compare the transcriptional profiles of human hyalocytes, retinal microglia (rMG) and classical, intermediate, and non-classical monocytes isolated from the same patients. Immunohistochemistry was applied for morphological characterization of human hyalocytes.
Pairwise analysis indicates distinct differences between hyalocytes and monocytes, whereas a high degree of similarity to rMG is apparent, with comparable expression levels of established microglia markers, such as TREM2, P2RY12, and TMEM119. Among the top expressed genes in hyalocytes, SPP1, CD74, and C3, were significantly upregulated when compared with monocytes. Despite the high level of similarity of hyalocytes and rMG, ten highly expressed genes in hyalocytes compared to microglia were identified, among them FOS, DUSP1, and EGR2.
This study reveals a high degree of similarity between hyalocytes and retinal microglia. Nevertheless, hyalocytes exhibit some expression differences that may adapt them to the specific needs of the vitreous and provide the basis for deciphering the multiple roles of this fascinating cell population in health and vitreoretinal diseases.
During salamander limb regeneration, only the structures distal to the amputation plane are regenerated, a property known as the rule of distal transformation. Multiple cell types are involved in ...limb regeneration; therefore, determining which cell types participate in distal transformation is important for understanding how the proximo-distal outcome of regeneration is achieved. We show that connective tissue-derived blastema cells obey the rule of distal transformation. They also have nuclear MEIS, which can act as an upper arm identity regulator, only upon upper arm amputation. By contrast, myogenic cells do not obey the rule of distal transformation and display nuclear MEIS upon amputation at any proximo-distal level. These results indicate that connective tissue cells, but not myogenic cells, are involved in establishing the proximo-distal outcome of regeneration and are likely to guide muscle patterning. Moreover, we show that, similarly to limb development, muscle patterning in regeneration is influenced by β-catenin signalling.
Epithelial, connective tissue and immune cells contribute in various ways to the pathophysiology of chronic rhinosinusitis (CRS). However, data of their distribution in upper airway mucosa are ...sparse. We aimed to provide quantitative, purely informative data on the distribution of these cell lineages and their coexpression patterns, which might help identifying, e.g., cells in the epithelium undergoing through epithelial–mesenchymal transition (EMT). For this purpose, we used immunofluorescence multichannel image cytometry (IMIC). We examined fixed paraffin-embedded tissue samples (FFPE) of six patients with chronic rhinosinusitis (CRS) and of three patients without CRS (controls). The direct-conjugated antibodies pancytokeratin, vimentin and CD45/CD18 were used for coexpression analysis in epithelial layer and lamina propria. Image acquisition and analysis were performed with TissueFAXS and StrataQuest, respectively. To distinguish positive from negative expression, a ratio between cell-specific immunostaining intensity and background was developed. Isotype controls were used as negative controls. Per patient, a 4.5-mm
2
tissue area was scanned and a median of 14,875 cells was recognized. The most common cell types were cytokeratin-single-positive (26%), vimentin-single-positive (13%) and CD45/CD18-single-positive with CD45/CD18–vimentin-double-positive cells (29%). In the patients with CRS, CD45/CD18-single-positive cells were 3–6 times higher compared to the control patients. In the epithelial layer, cytokeratin–vimentin-double-positive EMT cells were observed 3–5 times higher in the patients with CRS than in the control patients. This study provided quantitative data for the distribution of crucial cell types in CRS. Future studies may focus on the distribution and coexpression patterns of different immune cells in CRS or even cancer tissue.