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In humans, the clinical and molecular characterization of sporadic syndromes is often hindered by the small number of patients and the difficulty in developing animal models for severe dominant conditions. Here we show that the availability of large data sets of whole-genome sequences, high-density SNP chip genotypes and extensive recording of phenotype offers an unprecedented opportunity to quickly dissect the genetic architecture of severe dominant conditions in livestock. We report on the identification of seven dominant de novo mutations in CHD7, COL1A1, COL2A1, COPA, and MITF and exploit the structure of cattle populations to describe their clinical consequences and map modifier loci. Moreover, we demonstrate that the emergence of recessive genetic defects can be monitored by detecting de novo deleterious mutations in the genome of bulls used for artificial insemination. These results demonstrate the attractiveness of cattle as a model species in the post genomic era, particularly to confirm the genetic aetiology of isolated clinical case reports in humans.

Endometrial diseases are the major cause of subfertility in mares. The detection of subclinical diseases requires the histopathological examination of an endometrial biopsy. To prevent autolysis endometrial biopsies have to be fixed prior to their submission to the diagnostic laboratory. The most frequent type of chronic subclinical inflammation is non-suppurative endometritis. An immune mediated pathogenesis is suspected. Type 1 and type 2 adaptive immune responses exist; these are mediated by CD4+ helper T cells, CD8+ cytotoxic T cells, CD20+ B cells, plasma cells as well as polarized macrophages. In equine research, CD172a has been proposed as panmacrophage marker, CD14 and CD206 as markers of M1 and M2 polarisation, respectively; immunostaining for these antigens was only performed on cryostat sections of unfixed equine tissue. The aim of the present study was a) to establish an immunohistochemical method for the detection of macrophages in fixed equine tissue samples and b) to characterize the immune cell populations in fixed endometria with and without chronic endometritis. In regard to the former objective, immunostaining for CD172a, CD14 and CD206 was performed on paraffin embedded equine tissue with resident macrophages (lymph node, liver, small intestines) fixed either with IHC Zinc Fixative or 10 % neutral buffered formalin. In regard to the latter, immune cell populations in zinc fixed paraffin embedded (ZnFPE) endometrial biopsies of mares without endometritis (n = 4) and those with a superficial non-suppurative endometritis (n = 28) were compared. This study established an immunohistochemical method for the detection of the examined macrophage markers within fixed tissue samples, i.e. ZnFPE (CD172a, CD14, CD206) and formalin fixed paraffin embedded (FFPE) tissue after antigen retrieval (CD172a, CD206). It indicated that CD172a likely represents a pan-macrophage marker also in the equine endometrium. Immunohistochemical phenotyping showed that non-suppurative endometritis is mainly a T cell mediated disease with participation of plasma cells. In addition to CD4+ and CD8+ T cells, results indicate the presence of CD4-/CD8-double negative T cells. B cells and/or macrophages were observed in 15 cases. Endometrial macrophages expressed mainly CD172a and only rarely CD206, whereas CD14 was not detected. Notably, examined endometria showed a high variability in the numbers of T cell populations as well as plasma cells. This suggests the existence of subforms of this disease that may even differ in pathogenesis and etiology. The established method of immunophenotyping can be included in the routine diagnostic work-up of equine endometrial biopsies and can be beneficial for the identification of new therapeutic approaches. Its standardized application will likely assist to uncover immunological features that may predispose mares to develop persistent endometritis. The successful future application of this method will likely be beneficial for the genital health of individual mares, it also may help to prevent...

No abstract

Single-cell analysis of K562 human erythroleukemia cells by flow cytometry was used to demonstrate the specific role of iron in regulating transferrin receptors (TfRs) and to establish that TfR expression does not necessarily correlate with growth rate. Exogenous iron concentration in culture was manipulated by supplementing the medium with sera having different iron concentrations over the range 0.6 to 5.4 micrograms/ml, by the addition of iron in the form of FeCl3, iron-saturated serum, or diferric transferrin, and by the addition of the iron chelator Desferal (desferrioxamine). TfR expression was negatively correlated with exogenous iron content: any treatment that reduced exogenous iron supply by at least 15% resulted in as much as a 1.8-fold increase in external receptors, detected as binding by both transferrin and monoclonal anti-TfR antibodies, and a 1.5-fold increase in the pool of internal receptors, as detected by anti-TfR antibody binding. None of these treatments altered growth rate, total cellular protein content, protein synthetic rate, cell cycle distribution or cell size. The rapid (12 hr) and reversible induction of internal and external receptors by Desferal was inhibited by cycloheximide and therefore may have resulted from de novo synthesis and not just mobilization of internal receptor pool to the cell surface. The correlation between growth rate and TfR expression previously observed in these and other cells must be secondary to cellular mechanisms that maintain intracellular iron pools by regulating synthesis, recycling, and cell surface expression of TfRs.

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The hypothesis that PGK-B, like LDH-C4, is restricted to spermatogenic cells was explored by examining isozyme patterns in testes from mice depleted of germinal cells by surgical cryptorchism. In experimentally cryptorchized C57BL/10Sn males, decline in PGK-B activity paralleled decline in LDH-C4 activity and was correlated with degeneration of spermatocytes, spermatids, and spermatozoa. Trace amounts of these sperm isozymes found in cryptorchid testes after the depletion of maturing germ cells probably came from degenerated spermatids and spermatocytes and not from somatic testicular cells.

Linkage disequilibrium between the T/t complex and Pgk-2 - two loci flanking the murine major histocompatibility complex on chromosome 17 - has been found in a population of wild mice. By subjecting 78 wild males to progeny testing, we extracted 15 recessive t haplotypes of the T/t complex and assigned 12 of them to the tw5 complementation group. We also determined the allelic phase of T/t, Pgk-2, and Ce-2 on both chromosomes from each wild male. The allele Pgk-2c was always associated with a t haplotype, although the converse was not true.