45 research outputs found
Claudinâderived peptides are internalized via specific endocytosis pathways
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/91364/1/j.1749-6632.2012.06567.x.pd
Brain Endothelial Cell-Cell Junctions: How to âOpenâ the Blood Brain Barrier
The blood-brain barrier (BBB) is a highly specialized structural and biochemical barrier that regulates the entry of blood-borne molecules into brain, and preserves ionic homeostasis within the brain microenvironment. BBB properties are primarily determined by junctional complexes between the cerebral endothelial cells. These complexes are comprised of tight and adherens junctions. Such restrictive angioarchitecture at the BBB reduces paracellular diffusion, while minimal vesicle transport activity in brain endothelial cells limits transcellular transport. Under normal conditions, this largely prevents the extravasation of large and small solutes (unless specific transporters are present) and prevents migration of any type of blood-borne cell. However, this is changed in many pathological conditions. There, BBB disruption (âopeningâ) can lead to increased paracellular permeability, allowing entry of leukocytes into brain tissue, but also contributing to edema formation. In parallel, there are changes in the endothelial pinocytotic vesicular system resulting in the uptake and transfer of fluid and macromolecules into brain parenchyma. This review highlights the route and possible factors involved in BBB disruption in a variety of neuropathological disorders (e.g. CNS inflammation, Alzheimerâs disease, Parkinsonâs disease, epilepsy). It also summarizes proposed signal transduction pathways that may be involved in BBB âopeningâ
IL-12â and IL-23âmodulated T cells induce distinct types of EAE based on histology, CNS chemokine profile, and response to cytokine inhibition
The interleukin (IL)-12p40 family of cytokines plays a critical role in the development of experimental autoimmune encephalomyelitis (EAE). However, the relative contributions of IL-12 and IL-23 to the pathogenic process remain to be elucidated. Here, we show that activation of uncommitted myelin-reactive T cells in the presence of either IL-12p70 or IL-23 confers encephalogenicity. Adoptive transfer of either IL-12p70â or IL-23âpolarized T cells into naive syngeneic hosts resulted in an ascending paralysis that was clinically indistinguishable between the two groups. However, histological and reverse transcriptionâpolymerase chain reaction analysis of central nervous system (CNS) tissues revealed distinct histopathological features and immune profiles. IL-12p70âdriven disease was characterized by macrophage-rich infiltrates and prominent NOS2 up-regulation, whereas neutrophils and granulocyteâcolony-stimulating factor (CSF) were prominent in IL-23âdriven lesions. The monocyte-attracting chemokines CXCL9, 10, and 11 were preferentially expressed in the CNS of mice injected with IL-12p70âmodulated T cells, whereas the neutrophil-attracting chemokines CXCL1 and CXCL2 were up-regulated in the CNS of mice given IL-23âmodulated T cells. Treatment with antiâIL-17 or antiâgranulocyte/macrophage-CSF inhibited EAE induced by transfer of IL-23âpolarized, but not IL-12p70âpolarized, cells. These findings indicate that autoimmunity can be mediated by distinct effector populations that use disparate immunological pathways to achieve a similar clinical outcome
Vascular disruption and bloodâbrain barrier dysfunction in intracerebral hemorrhage
Abstract
This article reviews current knowledge of the mechanisms underlying the initial hemorrhage and secondary bloodâbrain barrier (BBB) dysfunction in primary spontaneous intracerebral hemorrhage (ICH) in adults. Multiple etiologies are associated with ICH, for example, hypertension, Alzheimerâs disease, vascular malformations and coagulopathies (genetic or drug-induced). After the initial bleed, there can be continued bleeding over the first 24Â hours, so-called hematoma expansion, which is associated with adverse outcomes. A number of clinical trials are focused on trying to limit such expansion. Significant progress has been made on the causes of BBB dysfunction after ICH at the molecular and cell signaling level. Blood components (e.g. thrombin, hemoglobin, iron) and the inflammatory response to those components play a large role in ICH-induced BBB dysfunction. There are current clinical trials of minimally invasive hematoma removal and iron chelation which may limit such dysfunction. Understanding the mechanisms underlying the initial hemorrhage and secondary BBB dysfunction in ICH is vital for developing methods to prevent and treat this devastating form of stroke.http://deepblue.lib.umich.edu/bitstream/2027.42/134526/1/12987_2014_Article_103.pd
Connexin 43 gap junctions contribute to brain endothelial barrier hyperpermeability in familial cerebral cavernous malformations type III by modulating tight junction structure
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154657/1/fsb2fj201700699r-sup-0003.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154657/2/fsb2fj201700699r.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154657/3/fsb2fj201700699r-sup-0002.pd
Systemic Delivery of an Adjuvant CXCR4-CXCL12 Signaling Inhibitor Encapsulated in Synthetic Protein Nanoparticles for Glioma Immunotherapy
Glioblastoma (GBM) is an aggressive primary brain cancer, with a 5 year survival of âŒ5%. Challenges that hamper GBM therapeutic efficacy include (i) tumor heterogeneity, (ii) treatment resistance, (iii) immunosuppressive tumor microenvironment (TME), and (iv) the blood-brain barrier (BBB). The C-X-C motif chemokine ligand-12/C-X-C motif chemokine receptor-4 (CXCL12/CXCR4) signaling pathway is activated in GBM and is associated with tumor progression. Although the CXCR4 antagonist (AMD3100) has been proposed as an attractive anti-GBM therapeutic target, it has poor pharmacokinetic properties, and unfavorable bioavailability has hampered its clinical implementation. Thus, we developed synthetic protein nanoparticles (SPNPs) coated with the transcytotic peptide iRGD (AMD3100-SPNPs) to target the CXCL2/CXCR4 pathway in GBM via systemic delivery. We showed that AMD3100-SPNPs block CXCL12/CXCR4 signaling in three mouse and human GBM cell cultures in vitro and in a GBM mouse model in vivo. This results in (i) inhibition of GBM proliferation, (ii) reduced infiltration of CXCR4+ monocytic myeloid-derived suppressor cells (M-MDSCs) into the TME, (iii) restoration of BBB integrity, and (iv) induction of immunogenic cell death (ICD), sensitizing the tumor to radiotherapy and leading to anti-GBM immunity. Additionally, we showed that combining AMD3100-SPNPs with radiation led to long-term survival, with âŒ60% of GBM tumor-bearing mice remaining tumor free after rechallenging with a second GBM in the contralateral hemisphere. This was due to a sustained anti-GBM immunological memory response that prevented tumor recurrence without additional treatment. In view of the potent ICD induction and reprogrammed tumor microenvironment, this SPNP-mediated strategy has a significant clinical translation applicability.Fil: Alghamri, Mahmoud S.. University Of Michigan Medical School; Estados UnidosFil: Banerjee, Kaushik. University Of Michigan Medical School; Estados UnidosFil: Mujeeb, Anzar A.. University Of Michigan Medical School; Estados UnidosFil: Mauser, Ava. University of Michigan; Estados UnidosFil: Taher, Ayman. University Of Michigan Medical School; Estados UnidosFil: Thalla, Rohit. University Of Michigan Medical School; Estados UnidosFil: McClellan, Brandon L.. University Of Michigan Medical School; Estados UnidosFil: Varela, Maria L.. University Of Michigan Medical School; Estados UnidosFil: Stamatovic, Svetlana M.. University Of Michigan Medical School; Estados UnidosFil: Martinez Revollar, Gabriela. University Of Michigan Medical School; Estados UnidosFil: Andjelkovic, Anuska V.. University Of Michigan Medical School; Estados UnidosFil: Gregory, Jason V.. University of Michigan; Estados UnidosFil: Kadiyala, Padma. University Of Michigan Medical School; Estados UnidosFil: Calinescu, Alexandra. University Of Michigan Medical School; Estados UnidosFil: JimĂ©nez, Jennifer A.. University of Michigan; Estados UnidosFil: Apfelbaum, April A.. University of Michigan; Estados UnidosFil: Lawlor, Elizabeth R.. University of Washington; Estados UnidosFil: Carney, Stephen. University of Michigan; Estados UnidosFil: Comba, Andrea. University Of Michigan Medical School; Estados Unidos. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Faisal, Syed Mohd. University Of Michigan Medical School; Estados UnidosFil: Barissi, Marcus. University Of Michigan Medical School; Estados UnidosFil: Edwards, Marta B.. University Of Michigan Medical School; Estados UnidosFil: Appelman, Henry. University Of Michigan Medical School; Estados UnidosFil: Sun, Yilun. Case Western Reserve University; Estados UnidosFil: Gan, Jingyao. University of Michigan; Estados UnidosFil: Ackermann, Rose. University of Michigan; Estados UnidosFil: Schwendeman, Anna. University of Michigan; Estados UnidosFil: Candolfi, Marianela. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de Investigaciones BiomĂ©dicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones BiomĂ©dicas; ArgentinaFil: Olin, Michael R.. University of Minnesota; Estados UnidosFil: Lahann, Joerg. University of Michigan; Estados UnidosFil: Lowenstein, Pedro R.. University of Michigan; Estados UnidosFil: Castro, Maria G.. University of Michigan; Estados Unido
Where did the ventricles go?
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90534/1/j.1471-4159.2011.07585.x.pd