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Background: α1-antitrypsin deficiency is most commonly caused by a mutation in exon-7 of SERPINA1 (SA1-ATZ), resulting in hepatocellular accumulation of a misfolded variant (ATZ). Human SA1-ATZ-transgenic (PiZ) mice exhibit hepatocellular ATZ accumulation and liver fibrosis. We hypothesized that disrupting the SA1-ATZ transgene in PiZ mice by in vivo genome editing would confer a proliferative advantage to the genome-edited hepatocytes, enabling them to repopulate the liver. Methods: To create a targeted DNA break in exon-7 of the SA1-ATZ transgene, we generated 2 recombinant adeno-associated viruses (rAAV) expressing a zinc-finger nuclease pair (rAAV-ZFN), and another rAAV for gene correction by targeted insertion (rAAV-TI). PiZmice were injected i.v. with rAAV-TI alone or the rAAV-ZFNs at a low (7.5 x 1010vg/mouse, LD) or a high dose (1.5x1011vg/mouse, HD), with or without rAAV-TI. Two weeks and 6 months after treatment, livers were harvested for molecular, histological, and biochemical analyses. Results: Two weeks after treatment, deep sequencing of the hepatic SA1-ATZ transgene pool showed 6%±3% or 15%±4% nonhomologous end joining in mice receiving LD or HD rAAV-ZFN, respectively, which increased to 36%±12% and 36%±12%, respectively, 6 months after treatment. Two weeks postinjection of rAAV-TI with LD or HD of rAAV-ZFN, repair by targeted insertion occurred in 0.10%±0.09% and 0.25%±0.14% of SA1-ATZ transgenes, respectively, which increased to 5.2%±5.0% and 33%±13%, respectively, 6 months after treatment. Six months after rAAV-ZFN administration, there was a marked clearance of ATZ globules from hepatocytes, and resolution of liver fibrosis, along with reduction of hepatic TAZ/WWTR1, hedgehog ligands, Gli2, a TIMP, and collagen content. Conclusions: ZFN-mediated SA1-ATZ transgene disruption provides a proliferative advantage to ATZ-depleted hepatocytes, enabling them to repopulate the liver and reverse hepatic fibrosis. [ABSTRACT FROM AUTHOR]

Zinc-finger nucleases (ZFNs) drive efficient genome editing by introducing a double-strand break into the targeted gene. Cleavage is induced when two custom-designed ZFNs heterodimerize upon binding DNA to form a catalytically active nuclease complex. The importance of this dimerization event for subsequent cleavage activity has stimulated efforts to engineer the nuclease interface to prevent undesired homodimerization. Here we report the development and application of a yeast-based selection system designed to functionally interrogate the ZFN dimer interface. We identified critical residues involved in dimerization through the isolation of cold-sensitive nuclease domains. We used these residues to engineer ZFNs that have superior cleavage activity while suppressing homodimerization. The improvements were portable to orthogonal domains, allowing the concomitant and independent cleavage of two loci using two different ZFN pairs. These ZFN architectures provide a general means for obtaining highly efficient and specific genome modification. [ABSTRACT FROM AUTHOR]

The relationship between object relations and child sexual abuse, physical abuse, and separation from parents was investigated in a clinical sample of 120 adult males with a history of sexual abuse, using the Bell Object Relations Reality Testing Inventory. Variables included gender of and relationship to perpetrator, age of onset, severity, frequency, duration, and number of abusers. Males with a history of abuse demonstrated greater object relations disturbances than the norm, scoring significantly higher on all object relations subscales. Disturbances in object relations were predicted by several sexual abuse variables, including abuse by a male, by both a male and female, by a relative, and by a stranger; and duration, frequency, and severity of abuse. Specific object relations problems were predicted by different patterns of sexual abuse. The implications of findings are discussed in relation to object relations theory, clinical applications for male victims, and future research. [ABSTRACT FROM AUTHOR]

The complexity of mental representations of self and others is a central dimension of personality structure and interpersonal functioning. The richness, differentiation, and integration of representations develops throughout childhood and adolescence and differs among individuals and among various psychopathological populations. The nature and development of mental representations is central to object relations theories in psychoanalysis, and has been receiving empirical attention in the social cognition literature. This article reports the development of instruments for measuring the complexity of mental representations from narrative data, based on an integration of object relations and social cognition research. The present study provides preliminary support for the validity of two measures, one for use with the TAT, and the other for use with interview data such as research interviews, psychotherapy transcripts, and early memories. [ABSTRACT FROM AUTHOR]