Biology subjects

Cerutti, C.

Publications and source records attributed to Cerutti, C..

3 recordsLinked to original sources

bioRxiv2020

On-chip perivascular niche with patient-derived glioma cells

Glioblastoma multiforme (GBM), is the most common and the most aggressive type of primary brain malignancy. Glioblastoma stem-like cells (GSCs) are able to migrate in vascular niches within or away from the tumour mass, increasing tumour resistance to patient treatments and contributing to relapses. To study individual GSCs migration and their interactions with the microenvironment in the vasculature, there is a need to develop a model of human blood vessels in vitro. Herein, we report a systematic study on the interaction between patient-derived glioma stem-like cell lines with different organotypic perivascular niche models. A microfluidic chip integrated with an extracellular matrix was fabricated to support the culture of rounded microvessels, formed with endothelial cells from three different organs, (1) human brain microvascular endothelial cells (hCMEC/D3), (2) human umbilical vein endothelial cells (HUVECs) and, (3) human lung microvascular endothelial cells (HMVEC-L). Three-dimensional (3D) cell culture retains selected adherent and tight junction markers of the endothelial cells, and the stemness-related genes of GSCs. We optimized the experimental protocol to perform qPCR, and western blot on the co-cultured GSCs with endothelial cells forming microvessels. Endpoint biological assays showed upregulation of neovascularization-related genes in endothelial cells (e.g., angiopoietins, vascular endothelial growth factor receptors) resulted after their co-culture with GBM cells. Moreover, we measured cancer cell speed and polarization during migration towards the endothelial cell formed vessel by live-cell imaging showing that organotypic (brain cancer cells - brain endothelial microvessel) interactions differ from those within non-tissue specific vascular niches. The development and optimization of this 3D microfluidic device could provide the next level of complexity of an in vitro system to study the influence of glioma cells on normal brain endothelium. More importantly, it enables the possibility to conduct comparative studies to dissect the influence of 3D culture, microvessel architecture and organotypic vessel types on glioma cells stemness and migration.

bioengineering↗

bioRxiv2020

Detection of Plasmodium vivax in a liver sample of a howler-monkey: one evidence more in favour of the identity between Plasmodium simium and P. vivax

IntroductionThe residual malaria of Atlantic Forest systems in Brazil occurs as an endemic disease with low frequency of cases. The chronological and spatial distance among the cases indicate an absence of fitness to the classical malaria cycle. This peculiar condition raised the suspicion of a reservoir, possibly the non-human primates. Simian and human malaria occur at the same places in that region, and there is already evidence of molecular identity between the simian parasites, Plasmodium simium and Plasmodium brasilianum, and the human parasites, Plasmodium vivax and Plasmodium malariae, respectively. Two different SNPs identified in the COX1 region of the Plasmodium vivax/simium of the Atlantic Forest reinforced its characterization as a zoonotic parasite. This finding supported the development of a PCR-RFLP protocol to identify such polymorphisms, and to monitor zoonotic malaria transmission. MethodsIn the present work, we tested the above-mentioned PCR-RFLP protocol in unprecedented mosquitoes and simian samples collected in Espirito Santo State, Brazil (ES). ResultsThe parasite found in the simian sample was P. vivax, contrary to what the protocol should indicate. In the mosquito samples, the protocol disclosed both forms of the parasite. ConclusionThis result suggests that the previously published pair of SNPs, and, consequently, the PCR-RFLP protocol, are not able to distinguish the dynamics of Plasmodium spp. circulation in the Atlantic Forest endemic area of ES.

molecular biology↗

bioRxiv2020

ERRα coordinates actin and focal adhesion dynamics

Cell migration depends on the dynamic organization of the actin cytoskeleton and assembly and disassembly of focal adhesions (FA). However the precise mechanisms coordinating these processes remain poorly understood. We previously identified the estrogen-related receptor (ERR) as a major regulator of cell migration. Here, we show that loss of ERR leads to abnormal accumulation of actin filaments that is associated with an increase in the level of inactive form of the actin-depolymerizing factor cofilin. We further show that ERR depletion decreases cell adhesion and promotes defective FA formation and turnover. Interestingly, specific inhibition of the RhoA-ROCK-LIMK-cofilin pathway rescues the actin polymerization defects resulting from ERR silencing, but not cell adhesion. Instead we found that MAP4K4 is a direct target of ERR and down-regulation of its activity rescues cell adhesion and FA formation in the ERR-depleted cells. Altogether, our results highlight a crucial role of ERR in coordinating the dynamic of actin network and focal adhesion through the independent regulation of the RhoA and MAP4K4 pathways.

cell biology↗