Variability of clinical chemical and hematological parameters, immunological parameters, and behavioral tests in data sets of the Mouse Phenome Database.

The use of mice as animal models in biomedical research allows the standardization of genetic background, housing conditions as well as experimental protocols, which all affect phenotypic variability. The phenotypic variability within the experimental unit determines the choice of the group size which is necessary for achieving valid and reproducible results. In this study, the variability of clinical chemical and hematological parameters which represent a comprehensive blood screen of laboratory mice, as well as of immunological parameters and behavioral tests was analyzed in data sets which have been submitted to the Mouse Phenome Database for mouse strains which are predominantly used in biomedical research.

New C3H Kit cancer mouse model develops late-onset malignant mammary tumors with high penetrance.

Gastro-intestinal stromal tumors and acute myeloid leukemia induced by activating stem cell factor receptor tyrosine kinase (KIT) mutations are highly malignant. Less clear is the role of KIT mutations in the context of breast cancer. Treatment success of KIT-induced cancers is still unsatisfactory because of primary or secondary resistance to therapy.

Distinct Morphological and Behavioural Alterations in ENU-Induced Heterozygous Mutant Mice.

(transient receptor potential cation channel, subfamily C, member 7; 862 amino acids) knockout mice are described showing no clear phenotypic alterations, therefore, the functional relevance of the gene remains unclear. A complementary approach for the functional analysis of a given gene is the examination of individuals harbouring a mutant allele of the gene. In the phenotype-driven Munich ENU mouse mutagenesis project, a high number of phenotypic parameters was used for establishing novel mouse models on the genetic background of C3H inbred mice.

Analysis of the sex-specific variability of blood parameters in data sets of the Mouse Phenome Database.

Objective: The use of mice as animal models in biomedical research allows the standardization of genetic background and environmental conditions, which both affect phenotypic variability. As the use of both sexes in experiments is strongly recommended, sex-specific phenotypic variability is discussed with regard to putative consequences on the group size which is necessary for achieving valid and reproducible results. In this study, the sex-specific variability of 25 clinical chemical and hematological parameters which represent a comprehensive blood screen of laboratory mice, was analyzed in data sets which have been submitted to the Mouse Phenome Database.

Mild maternal hyperglycemia in transgenic pigs causes impaired glucose tolerance and metabolic alterations in neonatal offspring.

Alongside the obesity epidemic, the prevalence of maternal diabetes is rising worldwide, and adverse effects on fetal development and metabolic disturbances in the offspring's later life have been described. To clarify whether metabolic programming effects are due to mild maternal hyperglycemia without confounding obesity, we investigated wild-type offspring of transgenic pigs, which are a novel genetically modified large-animal model expressing mutant insulin (INS) C93S in pancreatic β-cells. This mutation results in impaired glucose tolerance, mild fasting hyperglycemia and insulin resistance during late pregnancy.

Standardized, systemic phenotypic analysis reveals kidney dysfunction as main alteration of Kctd1 mutant mice.

Background: Increased levels of blood plasma urea were used as phenotypic parameter for establishing novel mouse models for kidney diseases on the genetic background of C3H inbred mice in the phenotype-driven Munich ENU mouse mutagenesis project. The phenotypically dominant mutant line HST014 was established and further analyzed.

Methods: Analysis of the causative mutation as well as the standardized, systemic phenotypic analysis of the mutant line was carried out.

Missense Mutation of POU Domain Class 3 Transcription Factor 3 in Pou3f3L423P Mice Causes Reduced Nephron Number and Impaired Development of the Thick Ascending Limb of the Loop of Henle.

During nephrogenesis, POU domain class 3 transcription factor 3 (POU3F3 aka BRN1) is critically involved in development of distinct nephron segments, including the thick ascending limb of the loop of Henle (TAL). Deficiency of POU3F3 in knock-out mice leads to underdevelopment of the TAL, lack of differentiation of TAL cells, and perinatal death due to renal failure. Pou3f3L423P mutant mice, which were established in the Munich ENU Mouse Mutagenesis Project, carry a recessive point mutation in the homeobox domain of POU3F3.

Generation and Standardized, Systemic Phenotypic Analysis of Pou3f3L423P Mutant Mice.

Increased levels of blood plasma urea were used as phenotypic parameter for establishing novel mouse models for kidney diseases on the genetic background of C3H inbred mice in the phenotype-driven Munich ENU mouse mutagenesis project. The phenotypically recessive mutant line HST011 was established and further analyzed. The causative mutation was detected in the POU domain, class 3 transcription factor 3 (Pou3f3) gene, which leads to the amino acid exchange Pou3f3L423P thereby affecting the conserved homeobox domain of the protein.

Screen for alterations of iron related parameters in N-ethyl-N-nitrosourea-treated mice identified mutant lines with increased plasma ferritin levels.

Iron is essential for numerous cellular processes. For diagnostic purposes iron-related parameters in patients are assessed by clinical chemical blood analysis including the analysis of ferritin, transferrin and iron levels. Here, we retrospectively evaluated the use of these parameters in the phenotype-driven Munich N-ethyl-N-nitrosourea mouse mutagenesis project for the generation of novel animal models for human diseases.

Uromodulin retention in thick ascending limb of Henle's loop affects SCD1 in neighboring proximal tubule: renal transcriptome studies in mouse models of uromodulin-associated kidney disease.

Uromodulin-associated kidney disease (UAKD) is a hereditary progressive renal disease which can lead to renal failure and requires renal replacement therapy. UAKD belongs to the endoplasmic reticulum storage diseases due to maturation defect of mutant uromodulin and its retention in the enlarged endoplasmic reticulum in the cells of the thick ascending limb of Henle's loop (TALH). Dysfunction of TALH represents the key pathogenic mechanism of UAKD causing the clinical symptoms of this disease.

Standardized, systemic phenotypic analysis of Slc12a1I299F mutant mice.

Background: Type I Bartter syndrome is a recessive human nephropathy caused by loss-of-function mutations in the SLC12A1 gene coding for the Na+-K+-2Cl- cotransporter NKCC2. We recently established the mutant mouse line Slc12a1I299F exhibiting kidney defects highly similar to the late-onset manifestation of this hereditary human disease. Besides the kidney defects, low blood pressure and osteopenia were revealed in the homozygous mutant mice which were also described in humans.

No amelioration of uromodulin maturation and trafficking defect by sodium 4-phenylbutyrate in vivo: studies in mouse models of uromodulin-associated kidney disease.

Uromodulin (UMOD)-associated kidney disease (UAKD) belongs to the hereditary progressive ER storage diseases caused by maturation defects of mutant UMOD protein. Current treatments of UAKD patients are symptomatic and cannot prevent disease progression. Two in vitro studies reported a positive effect of the chemical chaperone sodium 4-phenylbutyrate (4-PBA) on mutant UMOD maturation.

Standardized, systemic phenotypic analysis of Umod(C93F) and Umod(A227T) mutant mice.

Uromodulin-associated kidney disease (UAKD) summarizes different clinical features of an autosomal dominant heritable disease syndrome in humans with a proven uromodulin (UMOD) mutation involved. It is often characterized by hyperuricemia, gout, alteration of urine concentrating ability, as well as a variable rate of disease progression inconstantly leading to renal failure and histological alterations of the kidneys. We recently established the two Umod mutant mouse lines Umod(C93F) and Umod(A227T) on the C3H inbred genetic background both showing kidney defects analogous to those found in human UAKD patients.

Assessment of the genomic variation in a cattle population by re-sequencing of key animals at low to medium coverage.

Background: Genome- and population-wide re-sequencing would allow for most efficient detection of causal trait variants. However, despite a strong decrease of costs for next-generation sequencing in the last few years, re-sequencing of large numbers of individuals is not yet affordable. We therefore resorted to re-sequencing of a limited number of bovine animals selected to explain a major proportion of the population's genomic variation, so called key animals, in order to provide a catalogue of functional variants and a substrate for population- and genome-wide imputation of variable sites.

Type of uromodulin mutation and allelic status influence onset and severity of uromodulin-associated kidney disease in mice.

Uromodulin-associated kidney disease (UAKD) is a dominant heritable renal disease in humans which is caused by mutations in the uromodulin (UMOD) gene and characterized by heterogeneous clinical appearance. To get insights into possible causes of this heterogeneity of UAKD, we describe the new mutant mouse line Umod(C93F), leading to disruption of a putative disulfide bond which is also absent in a known human UMOD mutation, and compare the phenotype of this new mouse line with the recently published mouse line Umod(A227T). In both mutant mouse lines, which were both bred on the C3H background, the Umod mutations cause a gain-of-toxic function due to a maturation defect of the mutant uromodulin leading to a dysfunction of thick ascending limb of Henle's loop (TALH) cells of the kidney.

Imputation of high-density genotypes in the Fleckvieh cattle population.

Background: Currently, genome-wide evaluation of cattle populations is based on SNP-genotyping using ~ 54,000 SNP. Increasing the number of markers might improve genomic predictions and power of genome-wide association studies. Imputation of genotypes makes it possible to extrapolate genotypes from lower to higher density arrays based on a representative reference sample for which genotypes are obtained at higher density.

Blood Collection from Mice and Hematological Analyses on Mouse Blood.

Basic phenotyping of inbred mouse strains and genetically modified mouse models usually includes the determination of blood-based parameters as a diagnostic screen for genotype effects on metabolism and organ function. A broad range of analytes, including hematological parameters, can be reliably determined in mouse blood, if appropriate samples are available. Here we describe recommended techniques for blood collection from mice and the considerations that have to be taken into account to get adequate samples for hematological investigations.

Clinical Chemistry and Other Laboratory Tests on Mouse Plasma or Serum.

Besides hematological analyses, many other parameters, including clinical chemistry and endocrinological values, can be determined from mouse blood samples. For most of these tests, plasma or serum samples are used. Data obtained by these investigations provide indications of genotype effects on metabolism and organ functions.

Generation of N-ethyl-N-nitrosourea-induced mouse mutants with deviations in hematological parameters.

Research on hematological disorders relies on suitable animal models. We retrospectively evaluated the use of the hematological parameters hematocrit (HCT), hemoglobin (HGB), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), mean corpuscular volume (MCV), red blood cell count (RBC), white blood cell count (WBC), and platelet count (PLT) in the phenotype-driven Munich N-ethyl-N-nitrosourea (ENU) mouse mutagenesis project as parameters for the generation of novel animal models for human diseases. The analysis was carried out on more than 16,000 G1 and G3 offspring of chemically mutagenized inbred C3H mice to detect dominant and recessive mutations leading to deviations in the levels of the chosen parameters.

Transgenic pigs as models for translational biomedical research.

The translation of novel discoveries from basic research to clinical application is a long, often inefficient, and thus costly process. Accordingly, the process of drug development requires optimization both for economic and for ethical reasons, in order to provide patients with appropriate treatments in a reasonable time frame. Consequently, "Translational Medicine" became a top priority in national and international roadmaps of human health research.

Mutation of the Na(+)-K(+)-2Cl(-) cotransporter NKCC2 in mice is associated with severe polyuria and a urea-selective concentrating defect without hyperreninemia.

The bumetanide-sensitive Na(+)-K(+)-2Cl(-) cotransporter NKCC2, located in the thick ascending limb of Henle's loop, plays a critical role in the kidney's ability to concentrate urine. In humans, loss-of-function mutations of the solute carrier family 12 member 1 gene (SLC12A1), coding for NKCC2, cause type I Bartter syndrome, which is characterized by prenatal onset of a severe polyuria, salt-wasting tubulopathy, and hyperreninemia. In this study, we describe a novel chemically induced, recessive mutant mouse line termed Slc12a1(I299F) exhibiting late-onset manifestation of type I Bartter syndrome.

Transgenic pigs for xenotransplantation: selection of promoter sequences for reliable transgene expression.

Purpose Of Review: Appropriate expression of immunomodulatory and anticoagulant proteins on endothelial cells is essential to prevent rejection of vascularized porcine organs after transplantation into primates. Here, we review the promoter sequences used for the establishment of transgenic pigs, as organ donors for xenotransplantation.

Recent Findings: Transgenic pigs were produced using viral, chicken, mouse, human, and porcine promoter sequences with ubiquitous or cell type-specific activity.

Genetic modification of pigs as organ donors for xenotransplantation.

Transgenic pigs are promising donor organisms for xenotransplantation as they share many anatomical and physiological characteristics with humans. The most profound barrier to pig-to-primate xenotransplantation is the rejection of the grafted organ by a cascade of immune mechanisms commonly referred to as hyperacute rejection (HAR), acute humoral xenograft rejection (AHXR), immune cell-mediated rejection, and chronic rejection. Various strategies for the genetic modification of pigs facilitate tailoring them to be donors for organ transplantation.