by Keyword: Progress
Ferrer, Isidro, Andrés-Benito, Pol, Sala-Jarque, Julia, Gil, Vanessa, del Rio, José Antonio, (2020). Capacity for seeding and spreading of argyrophilic grain disease in a wild-type murine model; Comparisons with primary age-related tauopathy Frontiers in Molecular Neuroscience 13, 101
Argyrophilic grain disease (AGD) is a common 4R-tauopathy, causing or contributing to cognitive impairment in the elderly. AGD is characterized neuropathologically by pre-tangles in neurons, dendritic swellings called grains, threads, thorn-shaped astrocytes, and coiled bodies in oligodendrocytes in the limbic system. AGD has a characteristic pattern progressively involving the entorhinal cortex, amygdala, hippocampus, dentate gyrus, presubiculum, subiculum, hypothalamic nuclei, temporal cortex, and neocortex and brainstem, thus suggesting that argyrophilic grain pathology is a natural model of tau propagation. One series of WT mice was unilaterally inoculated in the hippocampus with sarkosyl-insoluble and sarkosyl-soluble fractions from “pure” AGD at the age of 3 or 7/12 months and killed 3 or 7 months later. Abnormal hyper-phosphorylated tau deposits were found in ipsilateral hippocampal neurons, grains (dots) in the hippocampus, and threads, dots and coiled bodies in the fimbria, as well as the ipsilateral and contralateral corpus callosum. The extension of lesions was wider in animals surviving 7 months compared with those surviving 3 months. Astrocytic inclusions were not observed at any time. Tau deposits were mainly composed of 4Rtau, but also 3Rtau. For comparative purposes, another series of WT mice was inoculated with sarkosyl-insoluble fractions from primary age-related tauopathy (PART), a pure neuronal neurofibrillary tangle 3Rtau + 4Rtau tauopathy involving the deep temporal cortex and limbic system. Abnormal hyper-phosphorylated tau deposits were found in neurons in the ipsilateral hippocampus, coiled bodies and threads in the fimbria, and the ipsilateral and contralateral corpus callosum, which extended with time along the anterior-posterior axis and distant regions such as hypothalamic nuclei and nuclei of the septum when comparing mice surviving 7 months with mice surviving 3 months. Astrocytic inclusions were not observed. Tau deposits were mainly composed of 4Rtau and 3Rtau. These results show the capacity for seeding and spreading of AGD tau and PART tau in the brain of WT mouse, and suggest that characteristics of host tau, in addition to those of inoculated tau, are key to identifying commonalities and differences between human tauopathies and corresponding murine models.
Keywords: Argyrophilic grain disease, Tauopathies, Tau, Seeding, Progression, Coiled Bodies, Primary age-related tauopathy
Torres, M., Martinez-Garcia, M. A., Campos-Rodriguez, F., Gozal, D., Montserrat, J. M., Navajas, D., Farré, R., Almendros, I., (2020). Lung cancer aggressiveness in an intermittent hypoxia murine model of postmenopausal sleep apnea Menopause 27, (6), 706-713
Intermittent hypoxia (IH)—a hallmark of obstructive sleep apnea (OSA)—enhances lung cancer progression in mice via altered host immune responses that are also age and sex-dependent. However, the interactions of menopause with IH on tumor malignant properties remain unexplored. Here, we aimed to investigate lung cancer outcomes in the context of ovariectomy (OVX)-induced menopause in a murine model of OSA.
Thirty-four female mice (C57BL/6, 12-week-old) were subjected to bilateral OVX or to Sham intervention. Six months after surgery, mice were pre-exposed to either IH or room air (RA) for 2 weeks. Then, 105 lung carcinoma (LLC1) cells were injected subcutaneously in the left flank, with IH or RA exposures continued for 4 weeks. Tumor weight, tumor invasion, and spontaneous lung metastases were assessed. Tumor-associated macrophages (TAMs) were isolated and subjected to flow cytometry polarity evaluation along with assessment of TAMs modulation of LLC1 proliferation in vitro. To determine the effect of IH and OVX on each experimental variable, a two-way analysis of variance was performed.
IH and OVX promoted a similar increase in tumor growth (2-fold; P = 0.05 and 1.74-fold; P < 0.05, respectively), and OVX-IH further increased it. Regarding lung metastasis, the concurrence of OVX in mice exposed to IH enhanced the number of metastases (23.7 ± 8.0) in comparison to those without OVX (7.9 ± 2.8; P < 0.05). The pro-tumoral phenotype of TAMS, assessed as M2/M1 ratio, was increased in OVX (0.06 ± 0.01; P < 0.01) and IH (0.06 ± 0.01; P < 0.01) compared with sham/RA conditions (0.14 ± 0.03). The co-culture of TAMS with naive LLC1 cells enhanced their proliferation only under IH.
In female mice, both the IH that is characteristically present in OSA and OVX as a menopause model emerge as independent contributors that promote lung cancer aggressiveness and seemingly operate through alterations in the host immune response.
Keywords: Animal models, Cancer progression, Intermittent hypoxia, Menopause, Obstructive sleep apnea, Ovariectomy
Campillo, N., Falcones, B., Otero, J., Colina, R., Gozal, D., Navajas, D., Farré, R., Almendros, I., (2019). Differential oxygenation in tumor microenvironment modulates macrophage and cancer cell crosstalk: Novel experimental settingand proof of concept Frontiers in Oncology 9, 43
Hypoxia is a common characteristic of many solid tumors that has been associated with tumor aggressiveness. Limited diffusion of oxygen generates a gradient of oxygen availability from the blood vessel to the interstitial space and may underlie the recruitment of macrophages fostering cancer progression. However, the available data based on the recruitment of circulating cells to the tumor microenvironment has been so far carried out by conventional co-culture systems which ignore the hypoxic gradient between the vessel to the tumor interstitium. Here, we have designed a novel easy-to-build cell culture device that enables evaluation of cellular cross-talk and cell migration while they are being simultaneously exposed to different oxygenation environments. As a proof-of-concept of the potential role of differential oxygenation among interacting cells we have evaluated the activation and recruitment of macrophages in response to hypoxic melanoma, breast, and kidney cancer cells. We found that hypoxic melanoma and breast cancer cells co-cultured with normoxic macrophages enhanced their directional migration. By contrast, hypoxic kidney cells were not able to increase their recruitment. We also identified well-described hypoxia-induced pathways which could contribute in the immune cell recruitment (VEGFA and PTGS2 genes). Moreover, melanoma and breast cancer increased their proliferation. However, oxygenation levels affected neither kidney cancer cell proliferation nor gene expression, which in turn resulted in no significant changes in macrophage migration and polarization. Therefore, the cell culture device presented here provides an excellent opportunity for researchers to reproduce the in vivo hypoxic gradients in solid tumors and to study their role in recruiting circulating cells to the tumor in specific types of cancer.
Keywords: Hypoxia gradient, Macrophage motility, Models of host-tumor interactions, Novel assay technology, Tumor progression
Tort, N., Salvador, J. P., Avino, A., Eritja, R., Comelles, J., Martinez, E., Samitier, J., Marco, M. P., (2012). Synthesis of steroid-oligonucleotide conjugates for a DNA site-encoded SPR immunosensor Bioconjugate Chemistry , 23, (11), 2183-2191
The excellent self-assembling properties of DNA and the excellent specificity of the antibodies to detect analytes of small molecular weight under competitive conditions have been combined in this study. Three oligonucleotide sequences (N(1)up, N(2)up, and N(3)up) have been covalently attached to three steroidal haptens (8, hG, and 13) of three anabolic-androgenic steroids (AAS), stanozolol (ST), tetrahydrogestrinone (THG), and boldenone (B), respectively. The synthesis of steroid oligonucleotide conjugates has been performed by the reaction of oligonucleotides carrying amino groups with carboxyl acid derivatives of steroidal haptens. Due to the chemical nature of the steroid derivatives, two methods for coupling the haptens and the ssDNA have been studied: a solid-phase coupling strategy and a solution-phase coupling strategy. Specific antibodies against ST, THG, and B have been used in this study to asses the possibility of using the self-assembling properties of the DNA to prepare biofunctional SPR gold chips based on the immobilization of haptens, by hybridization with the complementary oligonucleotide strands possessing SH groups previously immobilized. The capture of the steroid oligonucleotide conjugates and subsequent binding of the specific antibodies can be monitored on the sensogram due to variations produced on the refractive index on top of the gold chip. The resulting steroid oligonucleotide conjugates retain the hybridization and specific binding properties of oligonucleotides and haptens as demonstrated by thermal denaturation experiments and surface plasmon resonance (SPR).
Keywords: Directed protein immobilization, Plasmon resonance biosensor, Self-assembled monolayers, Label-free, Serum samples, Assay, Immunoassays, Antibodies, Progress, Binding