The rockefeller university

Psoriasis is now classified as an immune-mediated inflammatory disease ( IMID) of the skin. It is being recognized that patients with various IMIDs, including psoriasis, are at higher risk of developing "systemic" co-morbidities, e.g., cardiovascular disease (CVD), metabolic syndrome, and overt diabetes. In non-psoriatic individuals, the pathophysiology of obesity, aberrant adipocyte metabolism, diabetes, and CVDs involves immune-mediated or inflammatory pathways. IMIDs may impact these co-morbid conditions through shared genetic risks, common environmental factors, or common inflammatory pathways that are co-expressed in IMIDs and target organs. Given that pathogenic immune pathways in psoriasis are now well worked out and a large number of inflammatory mediators have been identified in skin lesions, in this review we will consider possible mechanistic links between skin inflammation and increased risks of (1) obesity or metabolic alterations and (2) CVD. In particular, we will discuss how well-established risk factors for CVD can originate from inflammation in other tissues.

The arrest of replication forks due to collisions with transcription complexes leads to genomic instability and cell death. Mechanisms that promote the progression of replication forks past transcription complexes are therefore essential for propagation and preservation of the genome. Recent studies of E. coli directly investigate the consequences of collisions of the replisome with RNAP polymerase (RNAP) in vitro and provide novel mechanisms by which these encounters may be resolved. Additionally, recent in vivo and in vitro studies support the longstanding hypothesis that auxiliary DNA helicases promote replication through roadblocks such as transcription complexes. Here we review past and recent advances that formulate our current understanding of how the bacterial replisome deals with transcription complexes along the path of chromosome duplication.

The Fanconi anemia (FA) pathway is responsible for interstrand crosslink repair. At the heart of this pathway is the FANCI-FAND2 (ID) complex, which, upon ubiquitination by the FA core complex, travels to sites of damage to coordinate repair that includes nucleolytic modification of the DNA surrounding the lesion and translesion synthesis. How the ID complex regulates these events is unknown. Here we describe a shRNA screen that led to the identification of two nucleases necessary for crosslink repair, FAN1 (KIAA1018) and EXDL2. FAN1 colocalizes at sites of DNA damage with the ID complex in a manner dependent on FAN1's ubiquitin-binding domain (UBZ), the ID complex, and monoubiquitination of FANCD2. FAN1 possesses intrinsic 5'-3' exonuclease activity and endonuclease activity that cleaves nicked and branched structures. We propose that FAN1 is a repair nuclease that is recruited to sites of crosslink damage in part through binding the ubiquitinated ID complex through its UBZ domain.

P>The Wiskott-Aldrich syndrome protein (WASP)-family verprolin homologous protein 1 (WAVE1) is a key regulator of Arp (actin-related protein) 2/3 complex-mediated actin polymerization. We have established previously that the state of phosphorylation of WAVE1 at three distinct residues controls its ability to regulate actin polymerization and spine morphology. Cyclin-dependent kinase 5 phosphorylates WAVE1 at Ser310, Ser397 and Ser441 to a high basal stoichiometry, resulting in inhibition of WAVE1 activity. Our previous and current studies show that WAVE1 can be dephosphorylated at all three sites and thereby activated upon stimulation of the D1 subclass of dopamine receptors and of the NMDA subclass of glutamate receptors, acting through cAMP and Ca2+ signaling pathways, respectively. Specifically, we have identified protein phosphatase-2A and protein phosphatase-2B as the effectors for these second messengers. These phosphatases act on different sites to mediate receptor-induced signaling pathways, which would lead to activation of WAVE1.

The immune response to stroke is comprised of inflammatory and regulatory processes. One cell type involved in both innate and adaptive immunity is the dendritic cell (DC). A DC population residing in the healthy brain (bDC) was identified using a transgenic mouse expressing enhanced yellow fluorescent protein (EYFP) under the promoter for the DC marker, CD11c (CD11c/EYFP Tg). To determine if bDC are involved in the immune response to cerebral ischemia, transient (40 min) middle cerebral artery occlusion (MCAO) followed by 6, 24, or 72 h reperfusion was conducted in CD11c/EYFP Tg mice. Our results demonstrated that DC accumulated in the ischemic hemisphere at 24 h post-MCAO-reperfusion, particularly in the border region of the infarct where T lymphocytes accrued. To distinguish resident bDC from the infiltrating peripheral DC, radiation chimeras [1. wild type (WT) hosts restored with CD11c/EYFP Tg bone marrow (BM) or 2. CD11c/EYFP Tg hosts restored with WT BM] were generated and examined by immunocytochemistry. These data confirmed that DC populating the core of the infarct at 72 h were of peripheral origin, whereas those in the border region were comprised primarily of resident bDC. The brain resident (CD45 intermediate) cells of CD11c/EYFP Tg mice were analyzed by flow cytometry. Compared to microglia, bDC displayed increased major histocompatibility class II (MHC II) and co-stimulatory molecules following MCAO-reperfusion. High levels of MHC II and the co-stimulatory molecule CD80 on bDC at 72 h corresponded to peak lymphocyte infiltration, and suggested a functional interaction between these two immune cell populations. (C) 2009 Elsevier Inc. All rights reserved.

A study reports a new method for wholesale labeling of neuronal proteins in situ that can visualize newly synthesized protein in a manner compatible with standard immunostaining techniques.

Although much prior research has focused on identifying the roles of major regulatory systems in health risks, the concept of allostatic load (AL) focuses on the importance of a more multisystems view of health risks. How best to operationalize allostatic load, however, remains the subject of some debate. We sought to test a hypothesized metafactor model of allostatic load composed of a number of biological system factors, and to investigate model invariance across sex and ethnicity. Biological data from 782 men and women, aged 32-47, from the Oakland, CA and Chicago, IL sites of the Coronary Artery Risk Development in Young Adults Study (CARDIA) were collected as part of the Year 15 exam in 2000. These include measures of blood pressure, metabolic parameters (glucose, insulin, lipid profiles, and waist circumference), markers of inflammation (interleukin-6, C-reactive protein, and fibrinogen), heart rate variability, sympathetic nervous system activity (12-hr urinary norepinephrine and epinephrine) and hypothalamic-pituitary-adrenal axis activity (diurnal salivary free cortisol). A "metafactor" model of AL as an aggregate measure of six underlying latent biological subfactors was found to fit the data, with the metafactor structure capturing 84% of variance of all pairwise associations among biological subsystems. There was little evidence of model variance across sex and/or ethnicity. These analyses extend work operationalizing AL as a multisystems index of biological dysregulation, providing initial support for a model of AL as a metaconstruct of inter-relationships among multiple biological regulatory systems, that varies little across sex or ethnicity. Am. J. Hum. Biol. 22:463-472,2010. (C)2006 Wiley-Liss, Inc.

In this study, we imaged the differentiation and migratory behavior of nascent plasma cells (PCs) in mouse lymph nodes by intravital microscopy. Pre-PCs exhibited a unique migration pattern characterized by long, linear paths that were randomly oriented. Although chemotaxis via G alpha i coupled-receptors has been implicated in PC migration, treatment with Pertussis toxin (Ptx), which ablates these signals, did not prevent movement of pre-PCs while it arrested other lymphocytes. In vitro, pre-PCs displayed processive amoeboid locomotion on surfaces coated with integrin ligand, whereas fully differentiated PCs moved slowly or were arrested. Both PC arrest and differentiation occurred in the medullary cords. Ptx treatment before PC differentiation blocked their accumulation in the medullary cords but pre-PCs still differentiated in other lymph node regions. Taken together, we suggest pre-PCs undergo a persistent random walk to find the medullary cords, where localized chemokines help retain these cells until they undergo differentiation and arrest in situ.

The frequency sensitivity of auditory hair cells in the inner ear varies with their longitudinal position in the sensory epithelium. Among the factors that determine the differential cellular response to sound is the resonance of a hair cell's transmembrane electrical potential, whose frequency correlates with the kinetic properties of the high-conductance Ca(2+)-activated K(+) (BK) channels encoded by a Slo (kcnma1) gene. It has been proposed that the inclusion of specific alternative axons in the Slo transcripts along the cochlea underlies the gradient of BK-channel kinetics. By analyzing the complete sequences of chicken Slo gene (cSlo) cDNAs from the chicken's cochlea, we show that most transcripts lack alternative exons. Transcripts with more than one alternative exon constitute only 10% of the total. Although the fraction of transcripts containing alternative exons increases from the cochlear base to the apex, the combination of alternative exons is not regulated. There is also a clear increase in the expression of BK transcripts with long carboxyl termini toward the apex. When long and short BK transcripts are expressed in HEK-293 cells, the kinetics of single-channel currents differ only slightly, but they are substantially slowed when the channels are coexpressed with the auxiliary beta subunit that occurs more widely at the apex. These results argue that the tonotopic gradient is not established by the selective inclusion of highly specific cSlo exons. Instead, a gradient in the expression of beta subunits slows BK channels toward the low-frequency apex of the cochlea.

BACKGROUND The outcomes of gene therapy to correct congenital immunodeficiencies are unknown. We reviewed long-term outcomes after gene therapy in nine patients with X-linked severe combined immunodeficiency (SCID-X1), which is characterized by the absence of the cytokine receptor common gamma chain. METHODS The nine patients, who lacked an HLA-identical donor, underwent ex vivo retrovirus-mediated transfer of gamma chain to autologous CD34+ bone marrow cells between 1999 and 2002. We assessed clinical events and immune function on long-term follow-up. RESULTS Eight patients were alive after a median follow-up period of 9 years (range, 8 to 11). Gene therapy was initially successful at correcting immune dysfunction in eight of the nine patients. However, acute leukemia developed in four patients, and one died. Transduced T cells were detected for up to 10.7 years after gene therapy. Seven patients, including the three survivors of leukemia, had sustained immune reconstitution; three patients required immunoglobulin-replacement therapy. Sustained thymopoiesis was established by the persistent presence of naive T cells, even after chemotherapy in three patients. The T-cell-receptor repertoire was diverse in all patients. Transduced B cells were not detected. Correction of the immunodeficiency improved the patients' health. CONCLUSIONS After nearly 10 years of follow-up, gene therapy was shown to have corrected the immunodeficiency associated with SCID-X1. Gene therapy may be an option for patients who do not have an HLA-identical donor for hematopoietic stem-cell transplantation and for whom the risks are deemed acceptable. This treatment is associated with a risk of acute leukemia.