Holm Zerbe - Academia.edu (original) (raw)

Papers by Holm Zerbe

Research paper thumbnail of Characterization of functional traits with focus on udder health in heifers with divergent paternally inherited haplotypes on BTA18

BMC Veterinary Research, Jul 11, 2019

Research paper thumbnail of Pregnancy-associated glycoproteins in cows with retained foetal membranes

Reproduction in Domestic Animals, 2017

Research paper thumbnail of Allele-biased expression of the bovine APOB gene associated with the cholesterol deficiency defect suggests cis-regulatory enhancer effects of the LTR retrotransposon insertion

Scientific Reports, Aug 5, 2022

Research paper thumbnail of A de novo frameshift mutation in ZEB2 causes polledness, abnormal skull shape, small body stature and subfertility in Fleckvieh cattle

Scientific Reports, 2020

Polledness in cattle is an autosomal dominant trait. Previous studies have revealed allelic heter... more Polledness in cattle is an autosomal dominant trait. Previous studies have revealed allelic heterogeneity at thepolledlocus and four different variants were identified, all in intergenic regions. In this study, we report a case of polled bull (FV-Polled1) born to horned parents, indicating a de novo origin of this polled condition. Using 50K genotyping and whole genome sequencing data, we identified on chromosome 2 an 11-bp deletion (AC_000159.1:g.52364063_52364073del;Del11) in the second exon ofZEB2gene as the causal mutation for this de novo polled condition. We predicted that the deletion would shorten the protein product ofZEB2by almost 91%. Moreover, we showed that all animals carryingDel11mutation displayed symptoms similar to Mowat-Wilson syndrome (MWS) in humans, which is also associated with genetic variations inZEB2. The symptoms in cattle include delayed maturity, small body stature and abnormal shape of skull. This is the first report of a de novo dominant mutation affec...

Research paper thumbnail of Binding of porcine spermatozoa to uterine epithelial cells modulates the female immune response and might indicate the formation of a pre-oviductal sperm reservoir

Bioscientifica Proceedings, 2020

Research paper thumbnail of In vivo model to study the impact of genetic variation on clinical outcome of mastitis in dairy heifers

Title: In vivo model to study the impact of genetic variation on clinical outcome of mastitis in ... more Title: In vivo model to study the impact of genetic variation on clinical outcome of mastitis in dairy heifers Background: In dairy herds, mastitis causes detrimental economic losses. Genetic selection offers a sustainable tool to select animals with reduced susceptibility towards postpartum diseases. Studying underlying mechanisms is important to assess the physiological processes that cause differences between selected haplotypes. Therefore, the objective of this study was to establish an in vivo infection model to study the impact of selecting for alternative paternal haplotypes in a particular genomic region on cattle chromosome 18 for mastitis susceptibility under defined conditions in dairy heifers. Results: At the start of pathogen challenge, no significant differences between the favorable (Q) and unfavorable (q) haplotypes were detected. Intramammary infection (IMI) with Staphylococcus aureus 1027 (S. aureus, n = 24, 96 h) or Escherichia coli 1303 (E. coli, n = 12, 24 h) wa...

Research paper thumbnail of Differentiating Staphylococcus aureus from Escherichia coli mastitis: S. aureus triggers unbalanced immune-dampening and host cell invasion immediately after udder infection

Scientific Reports, 2017

The etiology determines quality and extent of the immune response after udder infection (mastitis... more The etiology determines quality and extent of the immune response after udder infection (mastitis). Infections with Gram negative bacteria (e.g. Escherichia coli) will quickly elicit strong inflammation of the udder, fully activate its immune defence via pathogen receptor driven activation of IκB/NF-κB signaling. This often eradicates the pathogen. In contrast, Gram-positive bacteria (e.g. Staphylococcus aureus) will slowly elicit a much weaker inflammation and immune response, frequently resulting in chronic infections. However, it was unclear which immune regulatory pathways are specifically triggered by S. aureus causing this partial immune subversion. We therefore compared in first lactating cows the earliest (1–3 h) udder responses against infection with mastitis causing pathogens of either species. Global transcriptome profiling, bioinformatics analysis and experimental validation of key aspects revealed as S. aureus infection specific features the (i) failure to activating Iκ...

Research paper thumbnail of Pregnancy-associated glycoproteins in cows with retained fetal membranes

Research paper thumbnail of TLR ligands, but not modulators of histone modifiers, can induce the complex immune response pattern of endotoxin tolerance in mammary epithelial cells

Innate immunity, Feb 1, 2017

Excessive stimulation of the TLR4 axis through LPS reduces the expression of some cytokine genes ... more Excessive stimulation of the TLR4 axis through LPS reduces the expression of some cytokine genes in immune cells, while stimulating the expression of immune defense genes during a subsequent bacterial infection. This endotoxin tolerance (ET) is mediated via epigenetic mechanisms. Priming the udder of cows with LPS was shown to induce ET in mammary epithelial cells (MEC), thereby protecting the udder against reinfection for some time. Seeking alternatives to LPS priming we tried to elicit ET by priming MEC with either lipopeptide (Pam2CSK4) via the TLR2/6 axis or inhibitors of histone-modifying enzymes. Pre-incubation of MEC with Pam2CSK4 enhanced baseline and induced expression of bactericidal (β-defensin; SLPI) and membrane protecting factors ( SAA3, TGM3), while reducing the expression of cytokine- and chemokine-encoding genes ( TNF, IL1β) after a subsequent pathogen challenge, the latter, however, not as efficiently as after LPS priming. Pre-treating MEC with various inhibitors o...

Research paper thumbnail of Early transcriptional events in the udder and teat after intra-mammary Escherichia coli and Staphylococcus aureus challenge

Innate immunity, May 24, 2016

Intra-mammary bacterial infections can result in harmful clinical mastitis or subclinical mastiti... more Intra-mammary bacterial infections can result in harmful clinical mastitis or subclinical mastitis with persistent infections. Research during the last decades closely examined the pathophysiology of inflamed udders. Initial events after pathogen perception but before the onset of mastitis have not been examinedin vivo The objective of this study was to develop a mastitis model in cows by monitoring initial transcriptional pathogen-specific host response before clinical signs occur. We applied a short-term infection model to analyse transcripts encoding chemokines, cytokines and antimicrobial molecules in the teat cistern (TC) and lobulo-alveolar parenchyma (LP) up to 3 h after challenge withE andStaphylococcus aureus Both pathogens elicited an immune reaction by 1 h after challenge.Escherichia coliinduced all analysed factors (CCL20,CXCL8,TNF,IL6,IL12B,IL10,LAP,S100A9); however,S. aureusfailed to induceIL12B,IL10,LAPandS100A9expression. TheE. coli-induced up-regulation was 25-105 t...

Research paper thumbnail of Short Communication: Cellular Localization of Haptoglobin mRNA in the Experimentally Infected Bovine Mammary Gland

Journal of Dairy Science, 2007

Research paper thumbnail of Investigating the contribution of IL-17A and IL-17F to the host response during Escherichia coli mastitis

Veterinary Research, 2015

Research paper thumbnail of Location-specific expression of chemokines, TNF-α and S100 proteins in a teat explant model

Innate immunity, 2015

The distal compartments of the udder are the first to interact with invading pathogens. The regul... more The distal compartments of the udder are the first to interact with invading pathogens. The regulatory and effector functions of two major teat regions [Fürstenberg's rosette (FR); teat cistern (TC)] are largely unknown. The objective of this study was to establish an in vitro model with explants of the FR and the TC to analyse their response towards Escherichia coli LPS and Staphylococcus aureus lipoteichoic acid (LTA). Quantitative stereological analysis confirmed differences in the cellular composition of FR and TC explants. Chemokine (CXCL8, CCL5, CCL20) and TNF-α mRNA were expressed at low levels in both locations. Explant stimulation with LPS increased the mRNA abundance of all tested chemokines and TNF-α. Stimulation with LTA only induced CCL20 and CXCL8. LPS- and LTA-stimulated explant supernatants contained CXCL8 and CXCL3. Supernatants significantly attracted neutrophils in vitro. Compared with TC, the FR showed high constitutive mRNA expression of S100 proteins (A8, A...

Research paper thumbnail of Physiological routes from intra-uterine seminal contents to advancement of ovulation

Acta veterinaria Scandinavica, Jan 3, 2006

Whole boar semen or seminal plasma has been demonstrated to advance the time of ovulation in gilt... more Whole boar semen or seminal plasma has been demonstrated to advance the time of ovulation in gilts. As a means of clarifying this influence, the contribution of uterine lymphatics and their white cell populations has been examined. After duct visualisation with Evan's blue, lymph was sampled from a mesometrial vessel in eight pre-ovulatory gilts whose uterine lumen was infused simultaneously with whole semen in one ligated horn and saline in the contralateral ligated horn. Lymph was collected from cannulated vessels for periods of up to four hours under general anaesthesia. Thereafter, mesometrial lymph nodes, utero-tubal junction and uterine wall tissues were sampled. The proportion of nucleated cells in the sampled lymph increased towards the end of the collection period, but erythrocytes were found in all instances preventing a meaningful differentiation and identification of leukocytes. Prominent uterine lymph nodes were present in the mesometrium on both sides of the reprod...

Research paper thumbnail of Lipopolysaccharide pretreatment of the udder protects against experimental Escherichia coli mastitis

Innate Immunity, 2011

Exposure to pathogen-associated molecular patterns such as LPS can cause an immune refractory sta... more Exposure to pathogen-associated molecular patterns such as LPS can cause an immune refractory state in mammals known as endotoxin tolerance (ET), resulting in a decreased inflammatory response after pathogen contact. This ET concept was used to reduce the severity of an experimentally-induced clinical mastitis. Cows were pretreated with 1 µg LPS per udder quarter and challenged 72 h (group L72EC) or 240 h (group L240EC) later with 500 CFU Escherichia coli. Pretreated animals showed no leukopenia after challenge, no (L72EC), or only slightly (L240EC), elevated body temperature and significantly reduced systemic and local clinical scores compared with cows that were not pretreated. Whereas an increase of milk somatic cell count after the E. coli challenge was abrogated in L72EC animals, it was significantly delayed in the L240EC group. In both pretreated groups the bacterial load in milk was markedly reduced. Based on the expression of inflammation-related genes in lobulo-alveolar mam...

Research paper thumbnail of Escherichia coli, but notStaphylococcus aureustriggers an early increased expression of factors contributing to the innate immune defense in the udder of the cow

Veterinary Research, 2008

Research paper thumbnail of Gene expression profiling of bovine peripartal placentomes: detection of molecular pathways potentially involved in the release of foetal membranes

REPRODUCTION, 2011

The mechanisms underlying detachment of foetal membranes after birth in cows are still unclear. T... more The mechanisms underlying detachment of foetal membranes after birth in cows are still unclear. To address this problem in a systematic manner, we performed the first holistic transcriptome study of bovine placentomes antepartum (AP;n=4 cows) and intrapartum (IP;n=4 cows) using Affymetrix GeneChip Bovine Genome Arrays. Three placentomes were extracted from each cow, and tissue samples from the contact zones of the placentomes (foeto-maternal units) were recovered by systematic random sampling and processed for RNA extraction and for stereological quantification of cellular composition. Statistical analysis of microarray data (false discovery rate 1%) revealed 759 mRNAs with at least twofold higher levels in the samples of the AP group, whereas 514 mRNAs showed higher levels in the IP group. The differentially expressed genes were classified according to biological processes and molecular functions using the Functional Annotation Clustering tool of the DAVID Bioinformatics Resources....

Research paper thumbnail of Immunohistochemical assessment of progesterone, oestrogen and glucocorticoid receptors in bovine placentomes during pregnancy, induced parturition, and after birth with or without retention of fetal membranes

Reproduction, 2000

Steroid hormones play an important role in placental development. However, the exact cellular sit... more Steroid hormones play an important role in placental development. However, the exact cellular site of hormone action has not been evaluated in bovine placentomes. Thus, the present immunohistochemical study was designed to assess the distribution of progesterone receptors, oestrogen receptors and glucocorticoid receptors in bovine placentomes. Tissue specimens were obtained from cows at slaughter and from cattle during pre-term Caesarean section 27 h after prostaglandin administration, immediately after spontaneous parturition and from cattle that had retained the fetal membranes. Specific antibodies were used for receptor demonstration in tissue sections. Progesterone receptors were only detected in maternal connective tissue cells, whereas oestrogen receptors were also present in maternal crypt epithelium. At specific sites, both receptor immunoreactivities remained constant or changed significantly during pregnancy, were generally higher during Caesarean section and decreased pos...

Research paper thumbnail of DNA-remethylation around a STAT5-binding enhancer in the αS1-casein promoter is associated with abrupt shutdown of αS1-casein synthesis during acute mastitis

Journal of Molecular Endocrinology, 2006

Prolactin stimulates the expression of milk genes during lactation through the activation of STAT... more Prolactin stimulates the expression of milk genes during lactation through the activation of STAT5 transcription factors, which subsequently bind to their cognate target sequence on the promoters. Demethylation of 5methylCpG dinucleotides permits the tissue-specific accessibility of transcription factor-binding sites during development, but remethylation has not been shown to contribute to acute suppression of gene expression. We characterize functionally a novel STAT5-binding lactational enhancer in the far upstream promoter (~−10 kbp) of the bovine αS1-casein-encoding gene. This promoter area is hypo-methylated in the lactating udder only. Remethylation of this area accompanies an experimentally elicited acute shutdown of casein synthesis in fully lactating cows, whose udder quarters have experimentally been infected with a pathogenic E. coli strain. Within 24 h after infection, the relevant promoter area was remethylated from 10% of the DNA molecules in the uninfected control qua...

Research paper thumbnail of Investigation of mammary blood flow changes by transrectal colour Doppler sonography in anEscherichia colimastitis model

Journal of Dairy Research, 2010

The objectives of this preliminary investigation were to evaluate the feasibility of transrectal ... more The objectives of this preliminary investigation were to evaluate the feasibility of transrectal colour Doppler sonography (TCDS) for determining blood flow of the pudendoepigastric trunk in cows with experimentally inducedEscherichia coliMastitis. Five primiparous Holstein dairy cows, 4–6 months after calving, were examined in two trials. All monitored udder quarters were initially clinically healthy, somatic cell count (SCC) was <50 000 cells/ml and bacteriologically negative. The blood flow of the left and the right pudendoepigastric trunk was described by the blood flow volume (BFV). In the methodological part of the study, the intra-observer precision of the method was evaluated. The coefficients of variation of the BFV were 7·1% for the left and 9·4% for the right pudendoepigastric trunk. The intraclass correlation coefficients of the BFV were 0·99 (P<0·001) for the left and 0·75 (P=0·004) for the right vessel. BFV did not differ significantly between the left and the ri...

Research paper thumbnail of Characterization of functional traits with focus on udder health in heifers with divergent paternally inherited haplotypes on BTA18

BMC Veterinary Research, Jul 11, 2019

Research paper thumbnail of Pregnancy-associated glycoproteins in cows with retained foetal membranes

Reproduction in Domestic Animals, 2017

Research paper thumbnail of Allele-biased expression of the bovine APOB gene associated with the cholesterol deficiency defect suggests cis-regulatory enhancer effects of the LTR retrotransposon insertion

Scientific Reports, Aug 5, 2022

Research paper thumbnail of A de novo frameshift mutation in ZEB2 causes polledness, abnormal skull shape, small body stature and subfertility in Fleckvieh cattle

Scientific Reports, 2020

Polledness in cattle is an autosomal dominant trait. Previous studies have revealed allelic heter... more Polledness in cattle is an autosomal dominant trait. Previous studies have revealed allelic heterogeneity at thepolledlocus and four different variants were identified, all in intergenic regions. In this study, we report a case of polled bull (FV-Polled1) born to horned parents, indicating a de novo origin of this polled condition. Using 50K genotyping and whole genome sequencing data, we identified on chromosome 2 an 11-bp deletion (AC_000159.1:g.52364063_52364073del;Del11) in the second exon ofZEB2gene as the causal mutation for this de novo polled condition. We predicted that the deletion would shorten the protein product ofZEB2by almost 91%. Moreover, we showed that all animals carryingDel11mutation displayed symptoms similar to Mowat-Wilson syndrome (MWS) in humans, which is also associated with genetic variations inZEB2. The symptoms in cattle include delayed maturity, small body stature and abnormal shape of skull. This is the first report of a de novo dominant mutation affec...

Research paper thumbnail of Binding of porcine spermatozoa to uterine epithelial cells modulates the female immune response and might indicate the formation of a pre-oviductal sperm reservoir

Bioscientifica Proceedings, 2020

Research paper thumbnail of In vivo model to study the impact of genetic variation on clinical outcome of mastitis in dairy heifers

Title: In vivo model to study the impact of genetic variation on clinical outcome of mastitis in ... more Title: In vivo model to study the impact of genetic variation on clinical outcome of mastitis in dairy heifers Background: In dairy herds, mastitis causes detrimental economic losses. Genetic selection offers a sustainable tool to select animals with reduced susceptibility towards postpartum diseases. Studying underlying mechanisms is important to assess the physiological processes that cause differences between selected haplotypes. Therefore, the objective of this study was to establish an in vivo infection model to study the impact of selecting for alternative paternal haplotypes in a particular genomic region on cattle chromosome 18 for mastitis susceptibility under defined conditions in dairy heifers. Results: At the start of pathogen challenge, no significant differences between the favorable (Q) and unfavorable (q) haplotypes were detected. Intramammary infection (IMI) with Staphylococcus aureus 1027 (S. aureus, n = 24, 96 h) or Escherichia coli 1303 (E. coli, n = 12, 24 h) wa...

Research paper thumbnail of Differentiating Staphylococcus aureus from Escherichia coli mastitis: S. aureus triggers unbalanced immune-dampening and host cell invasion immediately after udder infection

Scientific Reports, 2017

The etiology determines quality and extent of the immune response after udder infection (mastitis... more The etiology determines quality and extent of the immune response after udder infection (mastitis). Infections with Gram negative bacteria (e.g. Escherichia coli) will quickly elicit strong inflammation of the udder, fully activate its immune defence via pathogen receptor driven activation of IκB/NF-κB signaling. This often eradicates the pathogen. In contrast, Gram-positive bacteria (e.g. Staphylococcus aureus) will slowly elicit a much weaker inflammation and immune response, frequently resulting in chronic infections. However, it was unclear which immune regulatory pathways are specifically triggered by S. aureus causing this partial immune subversion. We therefore compared in first lactating cows the earliest (1–3 h) udder responses against infection with mastitis causing pathogens of either species. Global transcriptome profiling, bioinformatics analysis and experimental validation of key aspects revealed as S. aureus infection specific features the (i) failure to activating Iκ...

Research paper thumbnail of Pregnancy-associated glycoproteins in cows with retained fetal membranes

Research paper thumbnail of TLR ligands, but not modulators of histone modifiers, can induce the complex immune response pattern of endotoxin tolerance in mammary epithelial cells

Innate immunity, Feb 1, 2017

Excessive stimulation of the TLR4 axis through LPS reduces the expression of some cytokine genes ... more Excessive stimulation of the TLR4 axis through LPS reduces the expression of some cytokine genes in immune cells, while stimulating the expression of immune defense genes during a subsequent bacterial infection. This endotoxin tolerance (ET) is mediated via epigenetic mechanisms. Priming the udder of cows with LPS was shown to induce ET in mammary epithelial cells (MEC), thereby protecting the udder against reinfection for some time. Seeking alternatives to LPS priming we tried to elicit ET by priming MEC with either lipopeptide (Pam2CSK4) via the TLR2/6 axis or inhibitors of histone-modifying enzymes. Pre-incubation of MEC with Pam2CSK4 enhanced baseline and induced expression of bactericidal (β-defensin; SLPI) and membrane protecting factors ( SAA3, TGM3), while reducing the expression of cytokine- and chemokine-encoding genes ( TNF, IL1β) after a subsequent pathogen challenge, the latter, however, not as efficiently as after LPS priming. Pre-treating MEC with various inhibitors o...

Research paper thumbnail of Early transcriptional events in the udder and teat after intra-mammary Escherichia coli and Staphylococcus aureus challenge

Innate immunity, May 24, 2016

Intra-mammary bacterial infections can result in harmful clinical mastitis or subclinical mastiti... more Intra-mammary bacterial infections can result in harmful clinical mastitis or subclinical mastitis with persistent infections. Research during the last decades closely examined the pathophysiology of inflamed udders. Initial events after pathogen perception but before the onset of mastitis have not been examinedin vivo The objective of this study was to develop a mastitis model in cows by monitoring initial transcriptional pathogen-specific host response before clinical signs occur. We applied a short-term infection model to analyse transcripts encoding chemokines, cytokines and antimicrobial molecules in the teat cistern (TC) and lobulo-alveolar parenchyma (LP) up to 3 h after challenge withE andStaphylococcus aureus Both pathogens elicited an immune reaction by 1 h after challenge.Escherichia coliinduced all analysed factors (CCL20,CXCL8,TNF,IL6,IL12B,IL10,LAP,S100A9); however,S. aureusfailed to induceIL12B,IL10,LAPandS100A9expression. TheE. coli-induced up-regulation was 25-105 t...

Research paper thumbnail of Short Communication: Cellular Localization of Haptoglobin mRNA in the Experimentally Infected Bovine Mammary Gland

Journal of Dairy Science, 2007

Research paper thumbnail of Investigating the contribution of IL-17A and IL-17F to the host response during Escherichia coli mastitis

Veterinary Research, 2015

Research paper thumbnail of Location-specific expression of chemokines, TNF-α and S100 proteins in a teat explant model

Innate immunity, 2015

The distal compartments of the udder are the first to interact with invading pathogens. The regul... more The distal compartments of the udder are the first to interact with invading pathogens. The regulatory and effector functions of two major teat regions [Fürstenberg's rosette (FR); teat cistern (TC)] are largely unknown. The objective of this study was to establish an in vitro model with explants of the FR and the TC to analyse their response towards Escherichia coli LPS and Staphylococcus aureus lipoteichoic acid (LTA). Quantitative stereological analysis confirmed differences in the cellular composition of FR and TC explants. Chemokine (CXCL8, CCL5, CCL20) and TNF-α mRNA were expressed at low levels in both locations. Explant stimulation with LPS increased the mRNA abundance of all tested chemokines and TNF-α. Stimulation with LTA only induced CCL20 and CXCL8. LPS- and LTA-stimulated explant supernatants contained CXCL8 and CXCL3. Supernatants significantly attracted neutrophils in vitro. Compared with TC, the FR showed high constitutive mRNA expression of S100 proteins (A8, A...

Research paper thumbnail of Physiological routes from intra-uterine seminal contents to advancement of ovulation

Acta veterinaria Scandinavica, Jan 3, 2006

Whole boar semen or seminal plasma has been demonstrated to advance the time of ovulation in gilt... more Whole boar semen or seminal plasma has been demonstrated to advance the time of ovulation in gilts. As a means of clarifying this influence, the contribution of uterine lymphatics and their white cell populations has been examined. After duct visualisation with Evan's blue, lymph was sampled from a mesometrial vessel in eight pre-ovulatory gilts whose uterine lumen was infused simultaneously with whole semen in one ligated horn and saline in the contralateral ligated horn. Lymph was collected from cannulated vessels for periods of up to four hours under general anaesthesia. Thereafter, mesometrial lymph nodes, utero-tubal junction and uterine wall tissues were sampled. The proportion of nucleated cells in the sampled lymph increased towards the end of the collection period, but erythrocytes were found in all instances preventing a meaningful differentiation and identification of leukocytes. Prominent uterine lymph nodes were present in the mesometrium on both sides of the reprod...

Research paper thumbnail of Lipopolysaccharide pretreatment of the udder protects against experimental Escherichia coli mastitis

Innate Immunity, 2011

Exposure to pathogen-associated molecular patterns such as LPS can cause an immune refractory sta... more Exposure to pathogen-associated molecular patterns such as LPS can cause an immune refractory state in mammals known as endotoxin tolerance (ET), resulting in a decreased inflammatory response after pathogen contact. This ET concept was used to reduce the severity of an experimentally-induced clinical mastitis. Cows were pretreated with 1 µg LPS per udder quarter and challenged 72 h (group L72EC) or 240 h (group L240EC) later with 500 CFU Escherichia coli. Pretreated animals showed no leukopenia after challenge, no (L72EC), or only slightly (L240EC), elevated body temperature and significantly reduced systemic and local clinical scores compared with cows that were not pretreated. Whereas an increase of milk somatic cell count after the E. coli challenge was abrogated in L72EC animals, it was significantly delayed in the L240EC group. In both pretreated groups the bacterial load in milk was markedly reduced. Based on the expression of inflammation-related genes in lobulo-alveolar mam...

Research paper thumbnail of Escherichia coli, but notStaphylococcus aureustriggers an early increased expression of factors contributing to the innate immune defense in the udder of the cow

Veterinary Research, 2008

Research paper thumbnail of Gene expression profiling of bovine peripartal placentomes: detection of molecular pathways potentially involved in the release of foetal membranes

REPRODUCTION, 2011

The mechanisms underlying detachment of foetal membranes after birth in cows are still unclear. T... more The mechanisms underlying detachment of foetal membranes after birth in cows are still unclear. To address this problem in a systematic manner, we performed the first holistic transcriptome study of bovine placentomes antepartum (AP;n=4 cows) and intrapartum (IP;n=4 cows) using Affymetrix GeneChip Bovine Genome Arrays. Three placentomes were extracted from each cow, and tissue samples from the contact zones of the placentomes (foeto-maternal units) were recovered by systematic random sampling and processed for RNA extraction and for stereological quantification of cellular composition. Statistical analysis of microarray data (false discovery rate 1%) revealed 759 mRNAs with at least twofold higher levels in the samples of the AP group, whereas 514 mRNAs showed higher levels in the IP group. The differentially expressed genes were classified according to biological processes and molecular functions using the Functional Annotation Clustering tool of the DAVID Bioinformatics Resources....

Research paper thumbnail of Immunohistochemical assessment of progesterone, oestrogen and glucocorticoid receptors in bovine placentomes during pregnancy, induced parturition, and after birth with or without retention of fetal membranes

Reproduction, 2000

Steroid hormones play an important role in placental development. However, the exact cellular sit... more Steroid hormones play an important role in placental development. However, the exact cellular site of hormone action has not been evaluated in bovine placentomes. Thus, the present immunohistochemical study was designed to assess the distribution of progesterone receptors, oestrogen receptors and glucocorticoid receptors in bovine placentomes. Tissue specimens were obtained from cows at slaughter and from cattle during pre-term Caesarean section 27 h after prostaglandin administration, immediately after spontaneous parturition and from cattle that had retained the fetal membranes. Specific antibodies were used for receptor demonstration in tissue sections. Progesterone receptors were only detected in maternal connective tissue cells, whereas oestrogen receptors were also present in maternal crypt epithelium. At specific sites, both receptor immunoreactivities remained constant or changed significantly during pregnancy, were generally higher during Caesarean section and decreased pos...

Research paper thumbnail of DNA-remethylation around a STAT5-binding enhancer in the αS1-casein promoter is associated with abrupt shutdown of αS1-casein synthesis during acute mastitis

Journal of Molecular Endocrinology, 2006

Prolactin stimulates the expression of milk genes during lactation through the activation of STAT... more Prolactin stimulates the expression of milk genes during lactation through the activation of STAT5 transcription factors, which subsequently bind to their cognate target sequence on the promoters. Demethylation of 5methylCpG dinucleotides permits the tissue-specific accessibility of transcription factor-binding sites during development, but remethylation has not been shown to contribute to acute suppression of gene expression. We characterize functionally a novel STAT5-binding lactational enhancer in the far upstream promoter (~−10 kbp) of the bovine αS1-casein-encoding gene. This promoter area is hypo-methylated in the lactating udder only. Remethylation of this area accompanies an experimentally elicited acute shutdown of casein synthesis in fully lactating cows, whose udder quarters have experimentally been infected with a pathogenic E. coli strain. Within 24 h after infection, the relevant promoter area was remethylated from 10% of the DNA molecules in the uninfected control qua...

Research paper thumbnail of Investigation of mammary blood flow changes by transrectal colour Doppler sonography in anEscherichia colimastitis model

Journal of Dairy Research, 2010

The objectives of this preliminary investigation were to evaluate the feasibility of transrectal ... more The objectives of this preliminary investigation were to evaluate the feasibility of transrectal colour Doppler sonography (TCDS) for determining blood flow of the pudendoepigastric trunk in cows with experimentally inducedEscherichia coliMastitis. Five primiparous Holstein dairy cows, 4–6 months after calving, were examined in two trials. All monitored udder quarters were initially clinically healthy, somatic cell count (SCC) was <50 000 cells/ml and bacteriologically negative. The blood flow of the left and the right pudendoepigastric trunk was described by the blood flow volume (BFV). In the methodological part of the study, the intra-observer precision of the method was evaluated. The coefficients of variation of the BFV were 7·1% for the left and 9·4% for the right pudendoepigastric trunk. The intraclass correlation coefficients of the BFV were 0·99 (P<0·001) for the left and 0·75 (P=0·004) for the right vessel. BFV did not differ significantly between the left and the ri...