Public Release:  JCI table of contents: Feb. 22, 2010

Journal of Clinical Investigation

EDITOR'S PICK: Blocking blood vessel formation prevents brain tumor recurrence in mice

Patients with glioblastoma multiforme (GBM), an extremely aggressive brain tumor, have a very poor prognosis. Despite high dose radiotherapy, 75% of patients die within two years, usually as a result of tumor recurrence within the irradiation field. Martin Brown and colleagues, at Stanford University School of Medicine, have now provided insight into the mechanism of such recurrence by studying a mouse model of GBM in which a human GBM cell line was grafted into the brain of mice, thus highlighting potential new therapeutic approaches to the treatment of GBM.

Formation of new blood vessels is an essential component of tumor recurrence. In the study, the authors found that in their GBM model, irradiation induced recruitment to the tumor site of cells able to facilitate blood vessel formation by a process known as vasculogenesis. Further analysis indicated that these cells were recruited by the soluble molecule SDF-1, which bound to the protein CXCR4 on the surface of the recruited cells. Importantly, disrupting the SDF-1/CXCR4 interaction prevented the recruitment of vasculogenic cells to the tumor site and thereby blocked postirradiation development of functional tumor vasculature, resulting in abrogation of tumor regrowth. The authors suggest that these data might be readily applicable to the clinic because a small molecule inhibitor of SDF-1/CXCR4 interactions is already clinically approved to obtain stem cells for transplantation.

In an accompanying commentary, Jeffrey Greenfield and David Lyden, at Weill Cornell Medical College, New York, discuss the importance of the study by Brown and colleagues and suggest that treatment for GMB should be tailored to target the specific blood vessel forming pathway operational at a given stage of disease.

TITLE: Inhibition of vasculogenesis, but not angiogenesis, prevents the recurrence of glioblastoma after irradiation in mice

AUTHOR CONTACT:
J. Martin Brown
Stanford University School of Medicine, California, USA.
Phone: 650.723.5881; Fax: 650.723.7382; E-mail: mbrown@stanford.edu.

View this article at: http://www.jci.org/articles/view/40283?key=a33226968525f5711bde

ACCOMPANYING COMMENTARY
TITLE: Resisting arrest: a switch from angiogenesis to vasculogenesis in recurrent malignant gliomas

AUTHOR CONTACT:
Jeffrey P. Greenfield
Weill Cornell Medical College, New York, New York, USA.
Phone: 212.746.3941; Fax: 212.746.8423; E-mail: jpgreenf@med.cornell.edu.

David Lyden
Weill Cornell Medical College, New York, New York, USA.
Phone: 212.746.3941; Fax: 212.746.8423; E-mail: dcl2001@med.cornell.edu.

View this article at: http://www.jci.org/articles/view/42345?key=3iujd7d5s4rdf5239ju0


VIROLOGY: Successfully modeling hepatitis B and C virus infection

Hepatitis B virus (HBV) and hepatitis C virus (HCV) infect liver cells, and persistent infection can lead to cirrhosis of the liver and/or a form of liver cancer known as hepatocellular carcinoma. Current small animal models of HBV and HCV infection are not particularly good, and new models are needed if we are to learn more about how these viruses operate and test new potential therapeutics. Inder Verma and colleagues, at the Salk Institute for Biological Studies, La Jolla, have now developed a human liver chimeric mouse model by transplanting a large number of human liver cells into mice lacking three proteins (Fah, Rag2, and Il-2r-gamma) to generate mice with livers in which 95% of the liver cells are human. Importantly, these mice could be infected with HBV and HCV, and mice infected with HCV were responsive to antiviral therapy. As mentioned by the authors and, in an accompanying commentary, Alexander Ploss and Charles Rice, at Rockefeller University, New York, this mouse model should prove useful not only for studying HBV and HCV infection and testing antiviral therapies but also for studying other infections microorganisms that target the liver such as malaria.

TITLE: Human liver chimeric mice provide a model for hepatitis B and C virus infection and treatment

AUTHOR CONTACT:
Inder M. Verma
Salk Institute for Biological Studies, La Jolla, California, USA.
Phone: 858.453.4100 ext. 1462; Fax: 858.558.7454; E-mail: verma@salk.edu.

View this article at: http://www.jci.org/articles/view/40094?key=88d7139eef5794adc164

ACCOMPANYING COMMENTARY
TITLE: New horizons for studying human hepatotropic infections

AUTHOR CONTACT:
Alexander Ploss
The Rockefeller University, New York, New York, USA.
Phone: 212.327.7066; Fax: 212.327.7048; E-mail: aploss@rockefeller.edu.

Charles M. Rice
The Rockefeller University, New York, NY, USA.
Phone: 212.327.7046; Fax: 212.327.7048; Email: ricec@rockefeller.edu.

View this article at: http://www.jci.org/articles/view/42338?key=4238dhsm34ikjw9xu2k3


VIROLOGY: New insight into Chikungunya virus infection from nonhuman primates

Chikungunya virus (CHIKV) is transmitted to humans from mosquitos. It causes a severely debilitating disease characterized by fever, rash, and pain in muscles and joints. Chikungunya disease is emerging as a considerable health problem in Africa, Asia, and the islands of the Indian Ocean. CHIKV infection is currently modeled in mice, but mouse models do not accurately mimic the disease seen in humans and are not useful for the development of vaccines and immune cell-based therapeutics. Now, Pierre Roques and colleagues, at the Commissariat à l'Energie Atomique, France, have successfully modeled CHIKV infection in cynomolgus macaques. Specifically, CHIKV infection in cynomolgus macaques was found to recapitulate the viral, clinical, and pathological features observed in CHIKV infected humans. Importantly, using this model of CHIKV infection, the authors determined that CHIKV infection persisted long term in joints, muscles, lymphoid organs, and liver, and that during this long-term infection the virus resided in immune cells known as macrophages. The authors hope this model of CHIKV infection will be useful to develop new therapeutic and/or prophylactic strategies, a sentiment echoed by Stephen Higgs and Sarah Ziegler, at the University of Texas Medical Branch, Galveston, in an accompanying commentary.

TITLE: Chikungunya disease in nonhuman primates involves long-term viral persistence in macrophages

AUTHOR CONTACT:
Pierre Roques
Service d'immunovirologie, Commissariat à l'Energie Atomique, Fontenay-aux-Roses, France.
Phone: 33.1.46.54.91.67; Fax: 33.1.46.54.77.26; E-mail: pierre.roques@cea.fr.

View this article at: http://www.jci.org/articles/view/40104?key=4803265af26198f13cd3

ACCOMPANYING COMMENTARY
TITLE: A nonhuman primate model of chikungunya disease

AUTHOR CONTACT:
Stephen Higgs
University of Texas Medical Branch, Galveston, Texas, USA.
Phone: 409.747.2426; Fax: 409.747.2437; E-mail: sthiggs@utmb.edu.

View this article at: http://www.jci.org/articles/view/42392?key=5s874984222348f4s89e


NEPHROLOGY: New gene linked to kidney disease

Nephronophthisis (NPHP) is the most common genetic cause of kidney failure in children. Ten causative genes (NPHP1-NPHP9 and NPHP11), all of which generate proteins that localize to a cellular complex known as the primary cilia-centrosome complex, have been identified previously. A team of researchers, at the University of Michigan Health System, Ann Arbor, and Duke University Medical Center, Durham, has now identified an association between mutations in the XPNPEP3 gene and an NPHP-like nephropathy in two consanguineous families, one in northern Finland and one in Turkey. Unlike all the known NPHP proteins, XPNPEP3 protein localizes to cellular compartments known as mitochondria. However, in vivo analysis in zebrafish indicated that XPNPEP3 protein has a role in ciliary function, as it degraded several ciliary cystogenic proteins. The authors therefore conclude that there is a link between mitochondria and ciliary dysfunction, a key component of NPHP. As highlighted by Erwin Böttinger, at Mount Sinai School of Medicine, New York, these data provide exciting new avenues of research for understanding ciliopathies, genetic disorders caused by damage to cellular structures known as primary cilia.

TITLE: Individuals with mutations in XPNPEP3, which encodes a mitochondrial protein, develop a nephronophthisis-like nephropathy

AUTHOR CONTACT:
Friedhelm Hildebrandt
University of Michigan Health System, Ann Arbor, Michigan, USA.
Phone: 734.615.7285; Fax: 734.615.1386; E-mail: fhilde@umich.edu.

Nicholas Katsanis
Duke University Medical Center, Durham, North Carolina, USA.
Phone: 919.613.4694; Fax: 919.684.1627; E-mail: katsanis@cellbio.duke.edu.

View this article at: http://www.jci.org/articles/view/40076?key=2670edbdb460768b2251

ACCOMPANYING COMMENTARY
TITLE: Lights on for aminopeptidases in cystic kidney disease

AUTHOR CONTACT:
Erwin P. Böttinger
Mount Sinai School of Medicine, New York, New York, USA.
Phone: 212.241.0800; Fax: 212.849.2643; E-mail: erwin.bottinger@mssm.edu.

View this article at: http://www.jci.org/articles/view/42378?key=54ejkhkif89845v6831f


DERMATOLOGY: Breaching the barrier: too much of the protein ELA2 impairs skin barrier function

Our skin has two crucial barrier functions: it protects against water loss and it prevents penetration of infectious agents and allergens. By studying mice and humans, a team of researchers, led by Alain Hovnanian and colleagues, at CHU Necker-Enfants Malades, France, has now generated data that indicate an important role for the protein elastase 2 (ELA2) in maintaining skin barrier function and suggest that ELA2 might have a role in the development of the rare genetic skin disease Netherton syndrome.

Netherton syndrome is caused by the inefficient inhibition of proteins known as serine proteases, which causes severe skin redness and scaling. In this study, the serine protease ELA2 was found to be expressed in both mouse and human skin cells (keratinocytes). Importantly, ELA2 was found to be hyperactive in skin from patients with Netherton syndrome. Further, transgenic mice overexpressing ELA2 in the epidermal layer of the skin exhibited cellular abnormalities characteristics of Netherton syndrome and these led to dehydration. As these data indicate that ELA2 is likely to have an important role in the skin barrier defect seen in patients with Netherton syndrome, the authors suggest that ELA2 might provide a new target for the treatment of Netherton syndrome.

TITLE: Elastase 2 is expressed in human and mouse epidermis and impairs skin barrier function in Netherton syndrome through filaggrin and lipid misprocessing

AUTHOR CONTACT:
Alain Hovnanian
CHU Necker-Enfants Malades, Department of Genetics, Paris, France.
Phone: 33.6.08.98.67.11; Fax: 33.1.71.19.64.20; E-mail: alain.hovnanian@inserm.fr.

View this article at: http://www.jci.org/articles/view/41440?key=6487f1d61ce6104ea750


DERMATOLOGY: Watching immune cell movement to and from the skin

Immune cells known as Tregs have an important role in preventing other immune cells from attacking the cells of our body and causing autoimmune diseases such as rheumatoid arthritis. A team of researchers, at Kyoto University Japan, and the Research Center for Allergy and Immunology, RIKEN, Japan, has now used mice engineered to express the photoconvertible fluorescence protein Kaede, which changes from green to red when exposed to violet light, to track Treg movement under physiologic conditions and during immune responses in the skin.

In the study, Tregs were found to move from the skin to designated regions for immune cell clustering known as draining lymph nodes. The extent of this trafficking was enhanced by skin inflammation but balanced under these conditions by movement of Tregs from the draining lymph nodes to the skin. As discussed by Hironori Matsushima and Akira Takashima, at the University of Toledo College of Medicine, in an accompanying commentary, these data provide new insight into the regulation of immune responses in the skin.

TITLE: Activated regulatory T cells are the major T cell type emigrating from the skin during a cutaneous immune response in mice

AUTHOR CONTACT:
Kenji Kabashima
Kyoto University, Kyoto, Japan.
Phone: 81.75.753.9502; Fax: 81.75.753.9500; E-mail: kaba@kuhp.kyoto-u.ac.jp.

Michio Tomura
Research Center for Allergy and Immunology, RIKEN, Yokohama City, Japan.
Phone: 81.45.503.9699; Fax: 81.45.503.9697; E-mail: tomura@rcai.riken.jp.

View this article at: http://www.jci.org/articles/view/40926?key=e05d84d8cce3f4f282a7

ACCOMPANYING COMMENTARY
TITLE: Bidirectional homing of Tregs between the skin and lymph nodes

AUTHOR CONTACT:
Akira Takashima
University of Toledo College of Medicine, Toledo, Ohio, USA.
Phone: 419.383.5423; Fax: 419.383.3002; E-mail: akira.takashima@utoledo.edu.

View this article at: http://www.jci.org/articles/view/42280?key=ij489s9cn2jkcxs98433

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