Enhanced VWF biosynthesis and elevated plasma VWF due to a natural variant in the murine Vwf gene

Abstract Both genetic and environmental influences contribute to the wide variation in plasma von Willebrand factor (VWF) levels observed in humans. Inbred mouse strains also have highly variable plasma VWF levels, providing a convenient model in which to study genetic modifiers of VWF. Previously, we identified a major modifier of VWF levels in the mouse (Mvwf1) as a regulatory mutation in murine Galgt2. We now report the identification of an additional murine VWF modifier (Mvwf2). Mvwf2 accounts for approximately 16% of the 8-fold plasma VWF variation (or ∼ 25% of the genetic variation) observed between the A/J and CASA/RkJ strains and maps to the murine Vwf gene itself. Twenty SNPs were identified within the coding regions of the A/J and CASA/RkJ Vwf alleles, and in vitro analysis of recombinant VWF demonstrated that a single SNP (+7970G>A) and the associated nonsynonymous amino acid change (R2657Q) confers a significant increase in VWF biosynthesis from the CASA/RkJ Vwf allele. This change appears to represent a unique gain of function that likely explains the mechanism of Mvwf2 in vivo. The identification of a natural Vwf gene variant among inbred mice affecting biosynthesis suggests that similar genetic variation may contribute to the wide range of VWF levels observed in humans.

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In vitro analysis of a transcription termination site for RNA polymerase II.

Molecular and Cellular Biology ◽

10.1128/mcb.10.11.5782 ◽

1990 ◽

Vol 10 (11) ◽

pp. 5782-5795 ◽

Cited By ~ 19

Author(s):

D K Wiest ◽

D K Hawley

Keyword(s):

Rna Polymerase ◽

Rna Polymerase Ii ◽

Dna Sequences ◽

Nuclear Extract ◽

Transcription Unit ◽

Dependent Manner ◽

Wide Range ◽

Vitro Analysis

Transcription from the adenovirus major late (ML) promoter has previously been shown to pause or terminate prematurely in vivo and in vitro at a site within the first intron of the major late transcription unit. We are studying the mechanism of elongation arrest at this site in vitro to define the DNA sequences and proteins that determine the elongation behavior of RNA polymerase II. Our assay system consists of a nuclear extract prepared from cultured human cells. With standard reaction conditions, termination is not observed downstream of the ML promoter. However, in the presence of Sarkosyl, up to 80% of the transcripts terminate 186 nucleotides downstream of the start site. Using this assay, we showed that the DNA sequences required to promote maximal levels of termination downstream of the ML promoter reside within a 65-base-pair region and function in an orientation-dependent manner. To test whether elongation complexes from the ML promoter were functionally homogeneous, we determined the termination efficiency at each of two termination sites placed in tandem. We found that the behavior of the elongation complexes was different at these sites, with termination being greater at the downstream site over a wide range of Sarkosyl concentrations. This result ruled out a model in which the polymerases that read through the first site were stably modified to antiterminate. We also demonstrated that the ability of the elongation complexes to respond to the ML termination site was promoter specific, as the site did not function efficiently downstream of a heterologous promoter. Taken together, the results presented here are not consistent with the simplest class of models that have been proposed previously for the mechanism of Sarkosyl-induced termination.

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A Combined Adjuvant TF–Al Consisting of TFPR1 and Aluminum Hydroxide Augments Strong Humoral and Cellular Immune Responses in Both C57BL/6 and BALB/c Mice

Vaccines ◽

10.3390/vaccines9121408 ◽

2021 ◽

Vol 9 (12) ◽

pp. 1408

Author(s):

Qiao Li ◽

Zhihua Liu ◽

Yi Liu ◽

Chen Liang ◽

Jiayi Shu ◽

...

Keyword(s):

Immune Responses ◽

Vaccine Development ◽

Inbred Mouse ◽

Effective Vaccine ◽

Mouse Strains ◽

Cellular Immune Responses ◽

Recombinant Hbsag ◽

Cellular Immune

TFPR1 is a novel adjuvant for protein and peptide antigens, which has been demonstrated in BALB/c mice in our previous studies; however, its adjuvanticity in mice with different genetic backgrounds remains unknown, and its adjuvanticity needs to be improved to fit the requirements for various vaccines. In this study, we first compared the adjuvanticity of TFPR1 in two commonly used inbred mouse strains, BALB/c and C57BL/6 mice, in vitro and in vivo, and demonstrated that TFPR1 activated TLR2 to exert its immune activity in vivo. Next, to prove the feasibility of TFPR1 acting as a major component of combined adjuvants, we prepared a combined adjuvant, TF–Al, by formulating TFPR1 and alum at a certain ratio and compared its adjuvanticity with that of TFPR1 and alum alone using OVA and recombinant HBsAg as model antigens in both BALB/c and C57BL/6 mice. Results showed that TFPR1 acts as an effective vaccine adjuvant in both BALB/c mice and C57BL/6 mice, and further demonstrated the role of TLR2 in the adjuvanticity of TFPR1 in vivo. In addition, we obtained a novel combined adjuvant, TF–Al, based on TFPR1, which can augment antibody and cellular immune responses in mice with different genetic backgrounds, suggesting its promise for vaccine development in the future.

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Immunosuppressive factor(s) specific for L-glutamic acid(50)-L- tyrosine(50) (GT). II. Presence of I-J determinants on the GT-suppressive factor

Journal of Experimental Medicine ◽

10.1084/jem.146.1.287 ◽

1977 ◽

Vol 146 (1) ◽

pp. 287-292 ◽

Cited By ~ 52

Author(s):

J Theze ◽

C Waltenbaugh ◽

ME Dorf ◽

B Benacerraf

Keyword(s):

T Cells ◽

Glutamic Acid ◽

Inbred Mouse ◽

Inbred Mouse Strain ◽

Antibody Responses ◽

Mouse Strains ◽

Suppressor T Cells ◽

Suppressor Factor

The responses to the synthetic antigens, L-glutamic acid(60)-L- alanine(30)-L-tyrosine(10) (GAT) and L-glutamic acid(50)-L-tyrosine(50) (GT) are controlled by genes in the I region of the mouse H-2 complex (1-3). Preimmunization of the mice bearing the H-2(p,q,s) nonresponder haplotypes with GAT stimulates the development of suppressor T cells that inhibit in vivo or in vitro antibody responses to GAT complexed to the immunogenic carrier, methylated bovine serum albumin (GAT-MBSA) (4). The copolymer GT is not immunogenic in any inbred mouse strain tested, and has a suppressive effect on the antibody responses to GT-MBSA in mouse strains bearing the H-2(d,f,k,s) haplotypes; suppressor T cells have been demonstrated to be responsible for specific GT suppression (3). We have obtained specific suppressive extracts from thymus and spleen cells of GAT-or GT-primed suppressor strains (5,6). The specific suppressive T-cell factors in the active extracts have been characterized (6,7) and appear similar to the carrier-specific suppressor factor described by Tada and Taniguchi (8). These products belong to a family of newly identified molecules coded for by the I region of the H-2 complex with affinity for antigen and helper (9,10) or suppressive (5-8) regulatory activity on the immune response. Recently, Tada et al. have reported that the keyhole limpet hemocyanin (KLH)-specific suppressor factor is coded for by the I-J subregion of the H-2 complex (11). We now demonstrate also that a GT-specific suppressor factor extracted from the spleens and thymuses of B10.BR (H-2(k)) mice bears determinants controlled by the I-J subregion of the H-2 complex.

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Animal models of Graves' disease

Acta Endocrinologica ◽

10.1530/eje.0.1420001 ◽

2000 ◽

pp. 1-8 ◽

Cited By ~ 29

Author(s):

M Ludgate

Keyword(s):

T Cells ◽

Mhc Class Ii ◽

Inbred Mice ◽

Inbred Mouse ◽

Nod Mice ◽

Autoimmune Response ◽

Mouse Strains ◽

Graves Disease ◽

Genetic Immunisation

Graves' disease (GD) is an autoimmune condition in which goitre and hyperthyroidism are induced by thyroid stimulating antibodies (TSAB) which mimic the action of thyrotrophin (TSH). The target of the autoimmune response is the thyrotrophin receptor (TSHR) and, since its cloning, a number of differing approaches have been adopted in an attempt to develop an animal model of GD. Methods in which synthetic peptides or fragments of the receptor produced in bacteria or insect cells have been injected into animals together with immunological adjuvants have had only limited success in inducing some of the signs and symptoms of GD. Genetic immunisation resulted in thyroiditis in the majority, but TSAB formation in only a minority, of treated inbred mice. Transfer of receptor in vitro primed T cells to syngeneic naive recipients, with priming either using a bacterial fusion protein or genetic immunisation, induced destructive thyroiditis in non-obese diabetic (NOD) mice but lymphocytic thyroiditis in BALBc mice. Furthermore, the orbits of 17/22 of the BALBc animals, but not the NOD animals, with thyroiditis had orbital changes similar to those seen in thyroid eye disease. TSAB and elevated thyroxine levels were induced in AKR/N mice injected with fibroblasts expressing the full length human TSHR and murine major histocompatibility complex (MHC) class II homologous to the recipient mice. No thyroiditis was induced but preliminary results from a different group using the same protocol suggest that receptor autoantibodies and thyroid dysfunction could be transferred using T cells primed in vitro with the receptor and MHC-II expressing cells. The majority of the studies described above have studied inbred mouse strains. In a novel departure, the NMR outbred strain has been treated by genetic immunisation with very promising results, including the induction of increased thyroxine levels in 4/30 female mice, accompanied by TSAB in addition to thyroiditis, and with signs of hyperactivity and orbital pathology. This review discusses the various protocols together with the information regarding the pathogenesis of GD which each has contributed, and concludes with an evaluation of how close we are to mimicking this polygenic, multifactorial disease.

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Mouse hepatitis virus type 4 (JHM strains). induced fatal central nervous system disease. I. genetic control and murine neuron as the susceptible site of disease.

Journal of Experimental Medicine ◽

10.1084/jem.153.4.832 ◽

1981 ◽

Vol 153 (4) ◽

pp. 832-843 ◽

Cited By ~ 84

Author(s):

R L Knobler ◽

M V Haspel ◽

M B Oldstone

Keyword(s):

Hepatitis Virus ◽

Inbred Mouse ◽

Neuronal Cells ◽

Mouse Hepatitis Virus ◽

Neuronal Cell ◽

Autosomal Gene ◽

Mouse Strains ◽

Target Cells

Mouse hepatitis virus (JHM strain) type 4 induces acute encephalitis followed by death in many strains of laboratory mice. Immunohistochemical study in vivo and analysis of mouse neuronal cells in vitro both indicate that the target cells in this infection is the neuron. Further, examination of several inbred mouse strains and neuronal cells from them shows that disease expression is controlled by a single autosomal gene action at the level of the neuronal cell. Susceptibility is dominant but not H-2 linked. However, cultured neuronal cells and macrophages from SJL/J mice, which are resistant to this infection, fail to make significant amounts of infectious virus after an appropriate viral inoculation. Apparently the defect is not at the level of the virus-cell receptor, because these cells, in part, express viral antigens.

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Anthrax Lethal Toxin Induces Ketotifen-Sensitive Intradermal Vascular Leakage in Certain Inbred Mice

Infection and Immunity ◽

10.1128/iai.74.2.1266-1272.2006 ◽

2006 ◽

Vol 74 (2) ◽

pp. 1266-1272 ◽

Cited By ~ 40

Author(s):

Yehoshua Gozes ◽

Mahtab Moayeri ◽

Jason F. Wiggins ◽

Stephen H. Leppla

Keyword(s):

Mast Cell ◽

Protective Antigen ◽

Inbred Mice ◽

Inbred Mouse ◽

Lethal Factor ◽

Clinical Signs ◽

Lethal Toxin ◽

Vascular Leakage ◽

Mouse Strains

ABSTRACT Bacillus anthracis lethal toxin (LT) is a bipartite toxin composed of protective antigen (PA) and lethal factor (LF). Injection of LT produces clinical signs characteristic of anthrax infection, including pleural edema and vascular collapse in various animal models. We utilized the classic Miles leakage assay to quantify vascular leakage in mice. LT injected intradermally induced leakage as early as 15 to 25 min in some inbred mouse strains, but not in others, whereas PA or LF individually did not induce leakage. A third component of anthrax toxin, edema factor, did not induce leakage alone or with PA. Leakage was quantified in eight mouse strains, and no correlation was found between sensitivity to intradermal leakage and sensitivity to the lethality of systemically administered LT. The leakage could be inhibited by ketotifen, an inhibitor of mast cell degranulation, but not by azelastine, a histamine receptor 1 antagonist, or by ketanserin, a serotonin 5-HT2A receptor antagonist. LT was cytotoxic to MC/9 mast cells (in vitro) by 7 h after toxin treatment but did not induce histamine release from these cells. Mast cell-deficient mice exhibited the leakage event and had no increased resistance to systemic LT. Human umbilical vein endothelial cells were resistant to LT over 12 h, with only 20% of cells succumbing by 24 h, suggesting that endothelial cell killing is not the cause of the rapid LT-mediated leakage event. We describe here a ketotifen-sensitive vascular leakage event induced by LT which is the most rapid in vivo or in vitro LT-mediated effect reported to date.

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hnRNP L regulates differences in expression of mouse integrin α2β1

Blood ◽

10.1182/blood-2005-12-4822 ◽

2006 ◽

Vol 107 (11) ◽

pp. 4391-4398 ◽

Cited By ~ 17

Author(s):

Yann Cheli ◽

Thomas J. Kunicki

Keyword(s):

Inbred Mouse ◽

Repeat Sequence ◽

Mrna Splicing ◽

Mouse Strains ◽

Enhancer Activity ◽

Ca Repeat ◽

Intron 1 ◽

Haplotype 1

AbstractThere is a 2-fold variation in platelet integrin α2β1 levels among inbred mouse strains. Decreased α2β1 in 4 strains carrying Itga2 haplotype 2 results from decreased affinity of heterogeneous ribonucleoprotein L (hnRNP L) for a 6 CA repeat sequence (CA6) within intron 1. Seven strains bearing haplotype 1 and a 21 CA repeat sequence at this position (CA21) express twice the level of platelet α2β1 and exhibit an equivalent gain of platelet function in vitro. By UV crosslinking and immunoprecipitation, hnRNP L binds more avidly to CA21, relative to CA6. By cell-free, in vitro mRNA splicing, decreased binding of hnRNP L results in decreased splicing efficiency and an increased proportion of alternatively spliced product. The splicing enhancer activity of CA21 in vivo is abolished by prior treatment with hnRNP L–specific siRNA. Thus, decreased surface α2β1 results from decreased Itga2 pre-mRNA splicing regulated by hnRNP L and depends on CA repeat length at a specific site in intron 1.

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Quantitative trait mapping reveals a regulatory axis involving peroxisome proliferator-activated receptors, PRDM16, transforming growth factor-β2 and FLT3 in hematopoiesis

Blood ◽

10.1182/blood-2011-07-365080 ◽

2011 ◽

Vol 118 (23) ◽

pp. 6078-6086 ◽

Cited By ~ 10

Author(s):

Serine Avagyan ◽

Francesca Aguilo ◽

Kenjiro Kamezaki ◽

Hans-Willem Snoeck

Keyword(s):

Stress Responses ◽

Transforming Growth Factor ◽

Inbred Mouse ◽

Mouse Strains ◽

Peroxisome Proliferator ◽

Peroxisome Proliferator Activated Receptor ◽

Serum Factors ◽

Peroxisome Proliferator Activated Receptors

Abstract Hematopoiesis is the process whereby BM HSCs renew to maintain their number or to differentiate into committed progenitors to generate all blood cells. One approach to gain mechanistic insight into this complex process is the investigation of quantitative genetic variation in hematopoietic function among inbred mouse strains. We previously showed that TGF-β2 is a genetically determined positive regulator of hematopoiesis. In the presence of unknown nonprotein serum factors TGF-β2, but not TGF-β1 or -β3, enhances progenitor proliferation in vitro, an effect that is subject to mouse strain-dependent variation mapping to a locus on chr.4, Tb2r1. TGF-β2–deficient mice show hematopoietic defects, demonstrating the physiologic role of this cytokine. Here, we show that TGF-β2 specifically and predominantly cell autonomously enhances signaling by FLT3 in vitro and in vivo. A coding polymorphism in Prdm16 (PR-domain-containing 16) underlies Tb2r1 and differentially regulates transcriptional activity of peroxisome proliferator-activated receptor-γ (PPARγ), identifying lipid PPAR ligands as the serum factors required for regulation of FLT3 signaling by TGF-β2. We furthermore show that PPARγ agonists play a FLT3-dependent role in stress responses of progenitor cells. These observations identify a novel regulatory axis that includes PPARs, Prdm16, and TGF-β2 in hematopoiesis.

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ADAM12: a genetic modifier of preclinical peripheral arterial disease

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00803.2014 ◽

2015 ◽

Vol 309 (5) ◽

pp. H790-H803 ◽

Cited By ~ 16

Author(s):

Ayotunde O. Dokun ◽

Lingdan Chen ◽

Mitsuharu Okutsu ◽

Charles R. Farber ◽

Surovi Hazarika ◽

...

Keyword(s):

Peripheral Arterial Disease ◽

Inbred Mouse ◽

Genetic Modifier ◽

Arterial Disease ◽

Endothelial Cell Proliferation ◽

Mouse Strains ◽

Trait Locus ◽

Peripheral Arterial

In prior studies from multiple groups, outcomes following experimental peripheral arterial disease (PAD) differed considerably across inbred mouse strains. Similarly, in humans with PAD, disease outcomes differ, even when there are similarities in risk factors, disease anatomy, arteriosclerotic burden, and hemodynamic measures. Previously, we identified a locus on mouse chromosome 7, limb salvage-associated quantitative trait locus 1 (LSq-1), which was sufficient to modify outcomes following experimental PAD. We compared expression of genes within LSq-1 in Balb/c mice, which normally show poor outcomes following experimental PAD, with that in C57Bl/6 mice, which normally show favorable outcomes, and found that a disintegrin and metalloproteinase gene 12 ( ADAM12) had the most differential expression. Augmentation of ADAM12 expression in vivo improved outcomes following experimental PAD in Balb/c mice, whereas knockdown of ADAM12 made outcomes worse in C57Bl/6 mice. In vitro, ADAM12 expression modulates endothelial cell proliferation, survival, and angiogenesis in ischemia, and this appeared to be dependent on tyrosine kinase with Ig-like and EGF-like domain 2 (Tie2) activation. ADAM12 is sufficient to modify PAD severity in mice, and this likely occurs through regulation of Tie2.

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Stress of Strains: Inbred Mice in Liver Research

Gene Expression ◽

10.3727/105221618x15337408678723 ◽

2019 ◽

Vol 19 (1) ◽

pp. 61-67 ◽

Cited By ~ 3

Author(s):

Arlin B. Rogers

Keyword(s):

Liver Disease ◽

Inbred Mice ◽

Inbred Mouse ◽

Disease Model ◽

Model Systems ◽

Mouse Strains ◽

Drug Induced ◽

Nonalcoholic Fatty Liver ◽

Induced Apoptosis

Inbred mice are the most popular animals used for in vivo liver research. These mice are genetically defined, readily available, less expensive to maintain than larger animals, and enjoy a broad array of commercial reagents for scientific characterization. C57BL/6 mice are the most commonly used strain. However, other strains discussed, including BALB/c, C3H, A/J, and FVB/N, may be better suited to a particular disease model or line of investigation. Understanding the phenotypes of different inbred mouse strains facilitates informed decision making during experimental design. Model systems influenced by strain-dependent phenotype include tissue regeneration, drug-induced liver injury (DILI; e.g., acetaminophen), fibrosis (e.g., carbon tetrachloride, CCl4), Fas-induced apoptosis, cholestasis, alcohol-induced liver disease and cirrhosis, nonalcoholic fatty liver disease and steatohepatitis (NAFLD/NASH), and hepatocellular carcinoma (HCC). Thoughtful consideration of the strengths and weaknesses of each inbred strain in a given model system will lead to more robust data and a clearer understanding of translational relevance to human liver disease.

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