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BACKGROUND & AIMS Augmenter of liver regeneration (ALR, encoded by GFER) is a widely distributed pleiotropic protein originally identified as a hepatic growth factor. However, little is known about its roles in hepatic physiology and pathology. We created mice with liver-specific deletion of ALR to study its function. METHODS We developed mice with liver-specific deletion of ALR (ALR-L-KO) using the albumin-Cre/LoxP system. Liver tissues were collected from ALR-L-KO mice and ALRfloxed/floxed mice (controls) and analyzed by histology, reverse-transcription PCR, immunohistochemistry, electron microscopy, and techniques to measure fibrosis and lipids. Liver tissues from patients with and without advanced liver disease were determined by immunoblot analysis. RESULTS Two weeks after birth, livers of ALR-L-KO mice contained low levels of ALR and ATP; they had reduced mitochondrial respiratory function and increased oxidative stress, compared with livers from control mice, and had excessive steatosis, and hepatocyte apoptosis. Levels of carbamyl-palmitoyl transferase 1a and ATP synthase subunit ATP5G1 were reduced in livers of ALR-L-KO mice, indicating defects in mitochondrial fatty acid transport and ATP synthesis. Electron microscopy showed mitochondrial swelling with abnormalities in shapes and numbers of cristae. From weeks 2–4 after birth, levels of steatosis and apoptosis decreased in ALR-L-KO mice, whereas numbers of ALR-expressing cells increased, along with ATP levels. However, at weeks 4–8 after birth, livers became inflamed, with hepatocellular necrosis, ductular proliferation, and fibrosis; hepatocellular carcinoma developed by 1 year after birth in nearly 60% of the mice. Hepatic levels of ALR were also low in ob/ob mice and alcohol-fed mice with liver steatosis, compared with controls. Levels of ALR were lower in liver tissues from patients with advanced alcoholic liver disease and nonalcoholic steatohepatitis than in control liver tissues. CONCLUSIONS We developed mice with liver-specific deletion of ALR, and showed that it is required for mitochondrial function and lipid homeostasis in the liver. ALR-L-KO mice provide a useful model for investigating the pathogenesis of steatohepatitis and its complications.

Herpes simplex virus type 1 (HSV-1)-specific CD8؉ T cells and the cytokine gamma interferon (IFN-␥) are persistently present in trigeminal ganglia (TG) harboring latent HSV-1. We define "latency" as the retention of functional viral genomes in sensory neurons without the production of infectious virions and "reactivation" as a multistep process leading from latency to virion assembly. CD8؉ T cells can block HSV-1 reactivation in ex vivo mouse TG cultures and appear to be the sole source of IFN-␥ in these cultures. Here we demonstrate that IFN-␥ alone can block HSV-1 reactivation in some latently infected neurons, and we identify points of intervention in the life cycle of the reactivating virus. Cell suspensions of TG that were latently infected with recombinant RE HSV-1 expressing enhanced green fluorescent protein from the promoter for infected cell protein 0 (ICP0) or glycoprotein C (gC) were depleted of endogenous CD8؉ or CD45 ؉ cells and cultured in the presence or absence of IFN-␥. Our results demonstrate that IFN-␥ acts on latently infected neurons to inhibit (i) HSV-1 reactivation, (ii) ICP0 promoter activity, (iii) gC promoter activity, and (iv) reactivation in neurons in which the ICP0 or gC promoter is active. Interestingly, we detected transcripts for ICP0, ICP4, and gH in neurons that expressed the ICP0 promoter but were prevented by IFN-␥ from reactivation and virion formation. Thus, the IFN-␥ blockade of HSV-1 reactivation from latency in neurons is associated with an inhibition of the expression of the ICP0 gene (required for reactivation) and a blockade of a step that occurs after the expression of at least some viral structural genes.During primary infection, herpes simplex virus type 1 (HSV-1) invades sensory neurons and is transported to neuronal cell bodies in sensory ganglia, where the viral genomes are retained in a latent (nonreplicating) state (30). In humans and some animal models, HSV-1 periodically reactivates from latency without overt stimuli (13, 17). With mice, this "spontaneous" HSV-1 reactivation from latency and shedding have not been demonstrated (38). However, a variety of stimuli, including physical and emotional stress, hyperthermia, and UV irradiation, are associated with HSV-1 reactivation from latency in mice, rabbits, guinea pigs, and humans (26,27).HSV latency is classically defined as the retention of a complete viral genome without the production of infectious virions; this definition accommodates the possible expression of a limited array of viral lytic genes while maintaining latency. This definition is accepted for other members of the herpesvirus family, all of which express some viral lytic cycle genes during latency (14, 25). The popular concept that HSV-1 latency is characterized by a complete lack of lytic gene expression has been called into question by several recent studies. Limited expression of HSV-1 lytic gene transcripts and proteins (the immediate-early [IE] ␣ gene, ICP4, and the ␤ genes encoding ICP8 and thymidine kinase) has been detected in mouse s...

Scaffolding-free pellet culture of hCSSC induces keratocyte gene expression patterns in these cells and secretion of an organized stroma-like ECM. These cells offer a novel potential for corneal bioengineering.

Herpes simplex virus type 1 (HSV-1) shedding from sensory neurons can trigger recurrent bouts of herpes stromal keratitis (HSK), an inflammatory response that leads to progressive corneal scarring and blindness. A mouse model of HSK is often used to delineate immunopathogenic mechanisms and bears many of the characteristics of human disease, but it tends to be more chronic and severe than human HSK. Loss of blink reflex (BR) in human HSK is common and due to a dramatic retraction of corneal sensory nerve termini in the epithelium and the nerve plexus at the epithelial/stromal interface. However, the relationship between loss of BR due to nerve damage and corneal pathology associated with HSK remains largely unexplored. Here, we show a similar retraction of corneal nerves in mice with HSK. Indeed, we show that much of the HSK-associated corneal inflammation in mice is actually attributable to damage to the corneal nerves and accompanying loss of BR and can be prevented or ameliorated by tarsorrhaphy (suturing eyelids closed), a clinical procedure commonly used to prevent corneal exposure and desiccation. In addition, we show that HSK-associated nerve retraction, loss of BR, and severe pathology all are reversible and regulated by CD4 ؉ T cells. Thus, defining immunopathogenic mechanisms of HSK in the mouse model will necessitate distinguishing mechanisms associated with the immunopathologic response to the virus from those associated with loss of corneal sensation. Based on our findings, investigation of a possible contribution of nerve damage and BR loss to human HSK also appears warranted. IMPORTANCEHSK in humans is a potentially blinding disease characterized by recurrent inflammation and progressive scarring triggered by viral release from corneal nerves. Corneal nerve damage is a known component of HSK, but the causes and consequences of HSK-associated nerve damage remain obscure. We show that desiccation of the corneal surface due to nerve damage and associated loss of BR severely exacerbates and prolongs inflammation-induced pathology in mice. Preventing corneal desiccation results in a milder and more transient HSK with variable scarring that mirrors HSK seen in most humans. We further show that nerve damage is reversible and regulated by CD4 ؉ T cells. Thus, we provide a mouse model that more closely resembles typical human HSK and suggest nerve damage is an important but largely overlooked factor in human disease.