| 1. |
- Regnault, C., et al.
(författare)
-
Microfluidic separation of parasites and parasite-infected cells from blood for the diagnosis of leishmaniasis
- 2016
-
Ingår i: 20th International Conference on Miniaturized Systems for Chemistry and Life Sciences, MicroTAS 2016. - 9780979806490 ; , s. 244-245
-
Konferensbidrag (refereegranskat)abstract
- Microfluidic techniques were applied to the separation of parasite and parasite-infected cells from blood to facilitate the detection of leishmaniasis, a disease representing a high burden in the developing world and for which new diagnostic tools are urgently needed. Leishmania mexicana promastigotes were successfully separated from red blood cells in a deterministic lateral displacement device. The mechanical properties of macrophages infected with L. mexicana were investigated using real-time deformability cytometry. In the early stage, we find that macrophages deform less than the control. The trend is reversed four days post infection while we see a continuous increase in cell size after parasitization.
|
|
| 2. |
|
|
| 3. |
|
|
| 4. |
- Luhr, JJ, et al.
(författare)
-
Maturation of Monocyte-Derived DCs Leads to Increased Cellular Stiffness, Higher Membrane Fluidity, and Changed Lipid Composition
- 2020
-
Ingår i: Frontiers in immunology. - : Frontiers Media SA. - 1664-3224. ; 11, s. 590121-
-
Tidskriftsartikel (refereegranskat)abstract
- Dendritic cells (DCs) are professional antigen-presenting cells of the immune system. Upon sensing pathogenic material in their environment, DCs start to mature, which includes cellular processes, such as antigen uptake, processing and presentation, as well as upregulation of costimulatory molecules and cytokine secretion. During maturation, DCs detach from peripheral tissues, migrate to the nearest lymph node, and find their way into the correct position in the net of the lymph node microenvironment to meet and interact with the respective T cells. We hypothesize that the maturation of DCs is well prepared and optimized leading to processes that alter various cellular characteristics from mechanics and metabolism to membrane properties. Here, we investigated the mechanical properties of monocyte-derived dendritic cells (moDCs) using real-time deformability cytometry to measure cytoskeletal changes and found that mature moDCs were stiffer compared to immature moDCs. These cellular changes likely play an important role in the processes of cell migration and T cell activation. As lipids constitute the building blocks of the plasma membrane, which, during maturation, need to adapt to the environment for migration and DC-T cell interaction, we performed an unbiased high-throughput lipidomics screening to identify the lipidome of moDCs. These analyses revealed that the overall lipid composition was significantly changed during moDC maturation, even implying an increase of storage lipids and differences of the relative abundance of membrane lipids upon maturation. Further, metadata analyses demonstrated that lipid changes were associated with the serum low-density lipoprotein (LDL) and cholesterol levels in the blood of the donors. Finally, using lipid packing imaging we found that the membrane of mature moDCs revealed a higher fluidity compared to immature moDCs. This comprehensive and quantitative characterization of maturation associated changes in moDCs sets the stage for improving their use in clinical application.
|
|
| 5. |
|
|
| 6. |
- Martinez-Sanchez, LD, et al.
(författare)
-
Epithelial RAC1-dependent cytoskeleton dynamics controls cell mechanics, cell shedding and barrier integrity in intestinal inflammation
- 2023
-
Ingår i: Gut. - : BMJ. - 1468-3288 .- 0017-5749. ; 72:2, s. 275-294
-
Tidskriftsartikel (refereegranskat)abstract
- Increased apoptotic shedding has been linked to intestinal barrier dysfunction and development of inflammatory bowel diseases (IBD). In contrast, physiological cell shedding allows the renewal of the epithelial monolayer without compromising the barrier function. Here, we investigated the role of live cell extrusion in epithelial barrier alterations in IBD.DesignTaking advantage of conditional GGTase and RAC1 knockout mice in intestinal epithelial cells (Pggt1biΔIECandRac1iΔIECmice), intravital microscopy, immunostaining, mechanobiology, organoid techniques and RNA sequencing, we analysed cell shedding alterations within the intestinal epithelium. Moreover, we examined human gut tissue and intestinal organoids from patients with IBD for cell shedding alterations and RAC1 function.ResultsEpithelialPggt1bdeletion led to cytoskeleton rearrangement and tight junction redistribution, causing cell overcrowding due to arresting of cell shedding that finally resulted in epithelial leakage and spontaneous mucosal inflammation in the small and to a lesser extent in the large intestine. Both in vivo and in vitro studies (knockout mice, organoids) identified RAC1 as a GGTase target critically involved in prenylation-dependent cytoskeleton dynamics, cell mechanics and epithelial cell shedding. Moreover, inflamed areas of gut tissue from patients with IBD exhibited funnel-like structures, signs of arrested cell shedding and impaired RAC1 function. RAC1 inhibition in human intestinal organoids caused actin alterations compatible with arresting of cell shedding.ConclusionImpaired epithelial RAC1 function causes cell overcrowding and epithelial leakage thus inducing chronic intestinal inflammation. Epithelial RAC1 emerges as key regulator of cytoskeletal dynamics, cell mechanics and intestinal cell shedding. Modulation of RAC1 might be exploited for restoration of epithelial integrity in the gut of patients with IBD.
|
|
