Immunological detection of pregnancy: Evidence for systemic immune modulation during early pregnancy in ruminants.

Mammalian pregnancy creates unique challenges for immune systems highly evolved to detect and eliminate invading pathogens. Recognition of the challenges created by gestating a semi-allogeneic fetus evolved from the discipline of transplantation biology and were informed by studies on the unique natural parabiosis that occurs when female calves are gestated with twin male fetuses. These pregnancies typically result in an intersex female termed a freemartin, which revealed insights into development of the male and female reproductive tracts. However, they also uncovered important clues on immune tolerance with wide-ranging implications to reproductive biology, transplantation biology and autoimmune disease. Many studies focused on identifying mechanisms through which the fetus evades maternal immune detection and elimination. These included studies characterizing immune interactions between the fetus and mother at the nourishing interface of the placenta and uterine endometrium. This immunological forbearance only occurs under high concentrations of circulating progesterone. Beyond the requirement for progesterone, there has been considerable progress towards understanding the effects of conceptus signals on maternal immune function. One common theme is that pregnancy induces a T helper 2 immune bias as shown in several mammalian species, including domestic ruminants. However, a growing body of evidence shows that the fetus not only evades, but also provokes immune responses locally in the uterus and in peripheral tissues. This is perhaps most dramatically illustrated by domestic ruminants where the conceptus secretes a unique interferon in the opening salvo of hormonal communication with the maternal immune system. The role of interferon tau in regulating expression of genes of the innate immune system in the uterus has been extensively studied. More recently, it was determined that these same genes are also induced in peripheral immune cells and other tissues throughout the body. In addition to interferon tau and progesterone, pregnancy associate glycoproteins and chaperonin 10 (aka Early Pregnancy Factor) are implicated in altering immune function both locally and systemically during pregnancy. While it is tempting to speculate that this activation of innate immunity is designed to counteract selective immunosuppression, knowledge of the importance of local and systemic immune activation to the success of pregnancy remains incomplete. This area remains fertile ground for developing better approaches to diagnose and treat infertility in domestic farm species and humans alike.

Mechanical shear controls bacterial penetration in mucus.

Mucus plays crucial roles in higher organisms, from aiding fertilization to protecting the female reproductive tract. Here, we investigate how anisotropic organization of mucus affects bacterial motility. We demonstrate by cryo electron micrographs and elongated tracer particles imaging, that mucus anisotropy and heterogeneity depend on how mechanical stress is applied. In shallow mucus films, we observe bacteria reversing their swimming direction without U-turns. During the forward motion, bacteria burrowed tunnels that last for several seconds and enable them to swim back faster, following the same track. We elucidate the physical mechanism of direction reversal by fluorescent visualization of the flagella: when the bacterial body is suddenly stopped by the mucus structure, the compression on the flagellar bundle causes buckling, disassembly and reorganization on the other side of the bacterium. Our results shed light into motility of bacteria in complex visco-elastic fluids and can provide clues in the propagation of bacteria-born diseases in mucus.

Symposium review: Immunological detection of the bovine conceptus during early pregnancy.

Infertility and subfertility reduce the economic viability of dairy production. Inflammation reduces conception rates in dairy cattle, but surprisingly little information exists about the populations and the functions of immune cells at the conceptus-maternal interface during the periattachment period in dairy cattle. Early pregnancy is accompanied by immune stimulation at insemination and conceptus secretion of IFN-τ, pregnancy-associated glycoproteins, prostaglandins, and other molecules whose effects on immune function during early pregnancy have not been determined. Our working hypothesis is that pregnancy induces changes in immune cell populations and functions that are biased toward immunological tolerance, tissue remodeling, and angiogenesis. This review summarizes current knowledge, starting with insemination and proceeding through early pregnancy, as this is the period of maximal embryo loss. Results indicated that early pregnancy is accompanied by a marked increase in the proportion of endometrial immune cells expressing markers for natural killer (CD335) cells and cytotoxic T cells (CD8) along with an increase in cells expressing major histocompatibility class II antigens (macrophages and dendritic cells). This is accompanied by increased abundance of mRNA for IL-15, a natural killer growth factor, and IL-10 in the endometrium during early pregnancy. Furthermore, expression of indoleamine 2,3 dioxygenase was 15-fold greater in pregnant compared with cyclic heifers at d 17, but then declined by d 20. This enzyme converts tryptophan to kynurenine, which alters immune function by creating a localized tryptophan deficiency and by activation of the aryl hydrocarbon receptor and induction of downstream tolerogenic mediators. Expression of the aryl hydrocarbon receptor is abundant in the bovine uterus, but its temporal and spatial regulation during early pregnancy have not been characterized. Pregnancy is also associated with increased expression of proteins known to inhibit immune activation, including programed cell death ligand-1 (CD274), lymphocyte activation gene-3 (CD223), and cytotoxic T-lymphocyte associated protein-4 (CD152). These molecules interact with receptors on antigen-presenting cells and induce lymphocyte tolerance. Current results support the hypothesis that early pregnancy signaling in dairy heifers involves changes in the proportions of immune cells in the endometrium as well as induction of molecules known to mediate tolerance. These changes are likely essential for uterine wall remodeling, placentation, and successful pregnancy.

Effects of early pregnancy on uterine lymphocytes and endometrial expression of immune-regulatory molecules in dairy heifers.

Natural killer (NK) cells are essential for establishment of human and rodent pregnancies. The function of these and other cytotoxic T cells (CTL) is controlled by stimulatory and inhibitory signaling. A role for cytotoxic cells during early pregnancy in cattle has not been described, but regulation of their function at the fetal-maternal interface is thought to be critical for conceptus survival. The hypothesis that the relative abundance of CTL and expression of inhibitory signaling molecules is increased by the conceptus during early pregnancy was tested. The proportions of lymphoid lineage cells and expression of inhibitory signaling molecules in the endometrium during early pregnancy in dairy heifers were determined using flow cytometry, immunofluorescence, and real-time PCR on days 17 and 20 of pregnancy and day 17 of the estrous cycle. Results revealed an increased percentage of NKp46+ and CD8+ cells in the uterus of pregnant heifers. Furthermore, a large percentage of uterine immune cells coexpressed these proteins. Compared to cyclic heifers, CD45+ uterine cells from pregnant heifers exhibited greater degranulation. Endometrium from pregnant heifers had greater mRNA abundance for the inhibitory molecules, CD274 and lymphocyte activating gene 3 (LAG3), and greater cytotoxic T lymphocyte-associated protein 4 (CTLA4), molecules that can interact with receptors on antigen-presenting cells and induce lymphocyte tolerance. This study demonstrates a dynamic regulation of both cytotoxic immune cells and tolerogenic molecules during the peri-implantation period that may be required to support establishment of pregnancy and placentation.

Embryo Mortality Around the Period of Maintenance of the Corpus Luteum Causes Alterations to the Ovarian Function of Lactating Dairy Cows.

Objectives were to identify cows with embryo mortality (EM) around the period of corpus luteum maintenance by interferon tau (IFNT) and to characterize ovarian function in cows that underwent EM. Lactating Holstein cows received artificial insemination (AI) (Day = 0) with semen or extender only. From Day 14 to 42 transrectal ultrasonography was performed daily to monitor ovarian dynamics and uterine contents whereas blood was collected every 48 h to determine ISG15 and MX2 mRNA abundance in blood mononuclear cells (Day 14 to 22 only) and determination of hormone concentrations. Cows were classified in the following reproductive status groups: cyclic (inseminated with extender; n = 15), pregnant (embryo present on Day 42; n = 23), no embryo (n = 23), and EM (n = 14). EM was defined as the presence of an embryo based on interferon-stimulated genes (ISG) mRNA abundance and concentrations of pregnancy-specific protein B (PSPB) above specific cutoff points but no embryo visualized by ultrasonography. Within the EM group, early EM (up to Day 22) was when ISG fold changes were above specific cutoff points from Day 18 to 22 and PSPB below 0.7 ng/ml on and after Day 24, whereas late EM (after Day 22) was when PSPB was above 0.7 ng/ml on or after Day 24 regardless of ISG expression. This experiment provided evidence that the combination of ISG expression patterns and PSPB concentrations is a reasonable method to determine EM around the period of corpus luteum maintenance by IFNT because cows with evidence of EM had patterns of ISG expression more similar to pregnant than cyclic cows or cows with no embryo. Within the EM group, only cows with late EM had delayed luteal regression and longer interovulatory intervals. No major alterations in follicular function were observed after the onset of luteolysis. Our results suggest that embryo development needs to continue beyond 22 days after AI to effectively prevent luteolysis and extend the luteal phase.

Changes in Myeloid Lineage Cells in the Uterus and Peripheral Blood of Dairy Heifers During Early Pregnancy.

Establishment of pregnancy requires interaction between the developing conceptus and the uterine mucosal immune system. Myeloid lineage cells (macrophages and dendritic cells) are key mediators of pregnancy in rodents and humans but relatively little is known regarding their role and distribution during early pregnancy in ruminants. We tested the hypothesis that myeloid lineage cell number, distribution, and function are altered during early pregnancy in dairy heifers. Dairy heifers were inseminated using sperm from a single bull (Day 0), and uteri and blood were collected at slaughter on Days 17 and 20 of pregnancy to investigate the response of myeloid lineage cells to the presence of a conceptus. Responses were compared to noninseminated heifers on Day 17 of the estrous cycle. Peripheral blood and uterine-derived immune cells were isolated magnetically and examined using flow cytometry. Immunohistochemical analysis was used to evaluate the spatial distribution of myeloid lineage cells in the endometrium and quantitative polymerase chain reaction was conducted to quantify abundance of mRNA transcripts associated with myeloid lineage cell function. Transcripts for major histocompatibility complex (MHC) II, cluster of differentiation (CD) 80, CD86, CD163, and indoleamine 2,3-dioxygenase (IDO) 1 were greater in endometrium of pregnant compared to cyclic heifers. Immunofluorescence analysis revealed increased labeling for MHCII and SIRPA in pregnant compared to cyclic heifers. There were approximately 50% more CD14+CD11c+ cells in the peripheral circulation of pregnant compared to cyclic heifers. A greater number of myeloid lineage cells were observed during early pregnancy, and this increase was most pronounced in and around the shallow glands. Furthermore, expression of molecules associated with a tolerogenic or alternatively activated phenotype of these cells also increased in pregnant heifers. The results support the hypothesis that myeloid lineage cells with a tolerogenic phenotype are involved in establishment of pregnancy in dairy heifers.

The Transcriptomic Evolution of Mammalian Pregnancy: Gene Expression Innovations in Endometrial Stromal Fibroblasts.

The endometrial stromal fibroblast (ESF) is a cell type present in the uterine lining of therian mammals. In the stem lineage of eutherian mammals, ESF acquired the ability to differentiate into decidual cells in order to allow embryo implantation. We call the latter cell type "neo-ESF" in contrast to "paleo-ESF" which is homologous to eutherian ESF but is not able to decidualize. In this study, we compare the transcriptomes of ESF from six therian species: Opossum (Monodelphis domestica; paleo-ESF), mink, rat, rabbit, human (all neo-ESF), and cow (secondarily nondecidualizing neo-ESF). We find evidence for strong stabilizing selection on transcriptome composition suggesting that the expression of approximately 5,600 genes is maintained by natural selection. The evolution of neo-ESF from paleo-ESF involved the following gene expression changes: Loss of expression of genes related to inflammation and immune response, lower expression of genes opposing tissue invasion, increased markers for proliferation as well as the recruitment of FOXM1, a key gene transiently expressed during decidualization. Signaling pathways also evolve rapidly and continue to evolve within eutherian lineages. In the bovine lineage, where invasiveness and decidualization were secondarily lost, we see a re-expression of genes found in opossum, most prominently WISP2, and a loss of gene expression related to angiogenesis. The data from this and previous studies support a scenario, where the proinflammatory paleo-ESF was reprogrammed to express anti-inflammatory genes in response to the inflammatory stimulus coming from the implanting conceptus and thus paving the way for extended, trans-cyclic gestation.

Low doses of bovine somatotropin enhance conceptus development and fertility in lactating dairy cows.

Objectives were to evaluate the effects of administering either one or two low doses of slow-release recombinant bovine somatotropin (bST) on hormone concentrations, conceptus development, and fertility in dairy cows. Cows from two farms were detected in estrus on or after 50 days postpartum (n = 1483), inseminated, and enrolled in the study (Day 0). Within farm, cows were blocked by parity and assigned randomly to receive a single placebo injection at insemination (control), a single injection with 325 mg of bST at insemination (S-bST), or two injections with 325 mg of bST administered on Days 0 and 14 (T-bST). From a subset of cows, blood was collected twice weekly from Day 0 to 42 for determination of hormone concentrations and on Day 19 for isolation of leucocytes and analysis of transcript abundance of selected interferon-stimulated genes. Pregnancy was diagnosed on Days 31 and 66, and ultrasonographic morphometry of the conceptus was performed on Days 34 and 48 in a subset of cows. Cows that received T-bST had increased plasma concentrations of GH and IGF1 for 4 wk, increased mRNA expression of ISG15 and RTP4 in leukocytes, earlier rise in the pregnancy-specific protein B in plasma of pregnant cows, increased conceptus size, and enhanced fertility. Cows that received S-bST had increased concentrations of GH and IGF1 for only 2 wk and it was insufficient to alter conceptus development and fertility. In conclusion, supplementation with low doses of bST during the pre- and peri-implantation periods enhanced conceptus development, reduced embryonic losses, and improved fertility in dairy cows.

Estrone and estrone sulfate concentrations in milk and milk fractions.

Dairy products naturally contain estrogens, and some consumer groups contend these estrogens cause adverse health effects. The objectives of this research were to characterize estrone (E(1)) and estrone sulfate (E(1)S) concentrations in milk from a large number of individual cows, in skim and fat fractions of milk, and in retail milk to provide food and nutrition practitioners with information to estimate potential consumption. Milk was from Holstein cows. Data are presented as means and standard deviations. Analysis of variance was used to determine differences in E(1) and E(1)S content of whole milk and its skim and fat fractions. Mean E(1) and E(1)S concentrations (n=173 cows) were 7.0±12.7 and 46.7±62.1 pg/mL (25.89±46.96 and 172.74±229.71 pmol/L), respectively. Analysis of milk fractions (n=50 samples) demonstrated that 55% of E(1) and 14% of E(1)S were associated with the fat fraction with the remainder associated with the skim fraction. Concentrations of E(1) and E(1)S in pasteurized-homogenized whole milk (n=8) averaged 10.3±0.6 and 85.9±7.3 pg/mL (38.09±2.22 and 317.74±27.00 pmol/L), respectively. Production rates of E(1) plus estradiol in human beings range from 54,000 to 630,000 ng/day. US Food and Drug administration guidelines state that no physiologic effects occur when consumption is ≤1% of the endogenous quantities produced by the segment of the population with the lowest daily production. This threshold value for intake would be 540 ng/day. Estimated total E(1) intake from three servings of whole milk was 68 ng/day, which represents 0.01% to 0.1% of daily production rates in human beings. These findings support levels below the current guidelines for safe consumption.

Effects of early conceptus signals on circulating immune cells: lessons from domestic ruminants.

While there are few similarities between mechanisms for extending corpus luteum (CL) function during early pregnancy in ruminants and primates, there is increasing evidence that conceptus-immune crosstalk in ruminants and primates affects the function of circulating immune cells at the very earliest stages of pregnancy. Most notable are changes in immune cell phenotypes with increased numbers of cells exhibiting the T regulatory phenotype and suppression of Th1 cytokines that promote tolerance to paternal alloantigens. Until recently, interferon τ produced by the ruminant trophectoderm was thought to act exclusively on the uterine endometrium; however, it is now clear that this unique embryonic interferon escapes the uterus and alters gene expression in the CL and in peripheral blood leukocytes (PBL). In fact, a large number of interferon-stimulated genes are now known to be increased during early pregnancy in PBL. What is not known is how this conceptus-immune system cross-talk affects maternal immune status outside the reproductive tract. It is attractive to hypothesize that some of these effects are designed to counter-balance progesterone-induced immunosuppression so as not to place the dam at a greater risk of infection on top of the tremendous stresses already induced by pregnancy. Furthermore, recent evidence suggests that pregnancy induced changes in peripheral immune cells may aid in orchestrating establishment of pregnancy. Existing evidence points toward a greater convergence of systemic immune responses to early pregnancy signaling between ruminants and primates.

Ovine endometrial expression of fibroblast growth factor (FGF) 2 and conceptus expression of FGF receptors during early pregnancy.

In ruminants, conceptus development beyond the blastocyst state requires input from uterine-derived factors. Fibroblast growth factor 2 (FGF2) is expressed by the bovine endometrium throughout the estrus cycle and early pregnancy and stimulates trophectoderm expression of interferon-tau, the maternal recognition of pregnancy factor in ruminants. The objective of this study was to examine the expression of FGF2 in ovine endometrium and peri-attachment conceptuses and FGF receptors (FGFR) in conceptuses. FGF2 mRNA was present in the ovine endometrium with specific localization within the luminal and glandular epithelium. No pregnancy-dependent changes in endometrial FGF2 mRNA abundance were detected until placental attachment was well underway. FGF2 protein was detected in the uterine lumen throughout the estrous cycle and early pregnancy. Concentrations of luminal FGF2 protein did not differ based on pregnancy status. However, uterine luminal FGF2 protein levels increased at days 12-13 after estrus in both cyclic and pregnant ewes. Ovine conceptuses collected at days 14-19 after mating contained transcripts for FGF2 and FGFR types 1, 2 and 3. In summary, FGF2 is expressed by the ovine endometrium and conceptus during early pregnancy, and peri-attachment conceptuses possess several FGFR types. Concentrations of FGF2 protein in the uterine lumen increase coincident with the initiation of pregnancy recognition in ewes. These observations support the concept that FGF2 and potentially other FGFs may affect conceptus development and/or gene expression during early pregnancy in ruminants.

Cellular localization and function of the antiviral protein, ovine Mx1 (oMx1): I. Ovine Mx1 is secreted by endometrial epithelial cells via an 'unconventional' secretory pathway.

PROBLEM: Embryonic loss is a major contributor to infertility. Understanding factors contributing to embryonic loss will aid in development of technologies to improve/regulate fertility in animals and humans. METHOD OF STUDY: We tested the hypothesis that the antiviral protein, ovine Mx1 (oMx1), is secreted by uterine epithelial cells. Uterine flushes were obtained from cyclic and early pregnant ewes and examined for levels of oMx1 protein. The pathway for ovine Mx1 secretion in ovine glandular epithelial (oGE) cells was determined using brefeldin A (BFA), an inhibitor of the conventional secretory pathway. Effects of BFA were determined using beta2-microglobulin (beta2MG) as a marker for the conventional secretory pathway, and interferon stimulated gene 15 (ISG15) and Galectin-1 (Gal-1) as markers for the unconventional secretory pathways. RESULTS: Ovine Mx1 protein levels were low in uterine flushes from cyclic ewes and levels increased in pregnant ewes after D 15. Ovine GE cells secreted oMx1 in response to interferon and secretion was not reduced by BFA, suggesting oMx1 was secreted via an unconventional secretory pathway. beta2MG secretion was reduced by BFA, whereas ISG15 and Gal-1 were not. CONCLUSION: This is the first report that the antiviral protein, oMx1, is secreted and provides evidence that secretion occurs via unconventional secretory pathway(s).

Cellular localization and function of the antiviral protein, ovine Mx1 (oMx1): II. The oMx1 protein is a regulator of secretion in an ovine glandular epithelial cell line.

PROBLEM: Embryonic loss is a major contributor to infertility. Understanding factors affecting embryonic loss will help increase fertility. METHOD OF STUDY: We investigated if ovine Mx1 (oMx1) mediated secretion by ovine glandular epithelial (oGE) cells using small interfering RNA (siRNA). Effects on secretion were examined through the conventional endoplasmic reticulum-Golgi pathway using beta2- microglobulin (beta2MG) as a marker, and interferon-stimulated gene 15 (ISG15) as a marker for unconventional secretion. RESULTS: Mx1 siRNA reduced oMx1 mRNA levels at 12 and 24 hr after IFN-tau treatment (P < 0.05), without affecting levels of oMx2, ISG15, 2',5'-oligoadenylate synthetas or beta2MG. Mx1 siRNA reduced Mx1 protein levels at 48 and 120 hr after treatment (P < 0.05) and protein levels remained low at 120 hr. Transient oMx1 knock-down reduced secretion of oMx1 (P < 0.01). ISG15 protein in secretions was reduced without affecting intracellular levels (P < 0.05). Levels of beta2MG in secretions were not affected by Mx1 siRNA. CONCLUSION: We showed that oMx1 protein is secreted by oGE cells and that reduction in oMx1 protein levels by siRNA reduced secretion of ISG15, but not beta2MG. Results support the hypothesis that oMx1 is a regulator of secretion through unconventional secretory pathway(s).

Growth hormone differentially regulates muscle myostatin1 and -2 and increases circulating cortisol in rainbow trout (Oncorhynchus mykiss).

Myostatin (MSTN) negatively regulates muscle growth in vertebrates. Salmonids produce two myostatin transcripts from separate genes. Surprisingly, quantitative analyses indicate different regulatory mechanisms for the two myostatin genes in rainbow trout. MSTN1 mRNA levels were elevated 26% following recombinant bovine growth hormone (rbGH) treatment, while MSTN2 mRNA levels were reduced 74% compared to controls. MSTN precursor protein (42kDa) levels were elevated in rbGH treated fish compared to controls. In addition, circulating cortisol levels were elevated 71% following rbGH treatment compared to controls. In treated and control fish, cortisol levels were elevated 245% at day 0 compared to subsequent days. Treated fish exhibited cortisol levels 207% higher than controls at 0.5 day, and remained at least 50% higher for 7 days following treatment. This pattern of change was positively correlated to MSTN1 mRNA levels. This is the first time a direct relationship has been reported between GH, cortisol, and myostatin. In addition, following rbGH administration, myosin protein concentrations in skeletal muscle samples increased, suggesting that GH regulates expression of the most abundant muscle protein. These results indicate the two myostatin genes are differentially regulated and may possess different functions in rainbow trout muscle, and suggests a possible interaction between GH, cortisol, and muscle growth.

The effects of recombinant bovine somatotropin (rbST) on tissue IGF-I, IGF-I receptor, and GH mRNA levels in rainbow trout, Oncorhynchus mykiss.

Numerous studies demonstrated that rbST increased growth rates in several fish species, and several species exhibit GH production in tissues other than the pituitary. The role of tissue GH and IGF-I in regulating fish growth is poorly understood. Therefore an experiment was conducted to examine the effects of rbST treatment on tissue GH, IGF-I, and IGF-I receptor-A (rA) expression in rainbow trout. Rainbow trout (550 +/- 10 g) received either intra-peritoneal injections of rbST (120 microg/g body weight) or vehicle on days 0 and 21, and tissue samples were collected on days 0, 0.5, 1, 3, 7, and 28 (n = 6/day/trt). Total RNA was isolated and assayed for steady-state levels of IGF-I, IGF-IrA, and GH mRNA using quantitative RT-PCR. Insulin-like growth factor-I mRNA levels increased in liver, gill, gonad, muscle, brain, and intestine in response to rbST treatment (P < 0.10). Liver IGF-I mRNA increased (P < 0.01) 0.5 day after treatment and remained elevated throughout the trial. Intestine IGF-I mRNA increased (P < 0.05) in treated fish from day 1 to day 3, then decreased to day 7 and increased again at day 28, and remained elevated above control levels throughout the trial. Gill IGF-I mRNA levels increased (P < 0.05) 1 day after treatment and remained elevated throughout the trial. Heart IGF-IrA mRNA levels decreased (P < 0.05) while gonad GH mRNA levels increased (P < 0.10) following rbST treatment. These results demonstrate that rbST treatment increased IGF-I mRNA levels in extra-hepatic tissues, and decreased heart IGF-IrA and increased gonad GH mRNA levels. Because the primary source for endocrine IGF-I is liver, the increased IGF-I mRNA reported in extra-hepatic tissues may indicate local paracrine/autocrine actions for IGF-I for local physiological functions.

Comparative gene-based in silico analysis of transcriptomes in different bovine tissues and (or) organs.

A gene-based approach was used to annotate 322,168 cattle expressed sequence tags (ESTs) based on human genes in order to census the transcriptomes, analyze their expression similarities, and identify genes preferentially expressed in different bovine tissues and (or) organs. Of the 34,157 human coding genes used in a standalone BLAST search, 14,928 could be matched with provisional orthologous sequences in a total of 230,135 bovine ESTs. The remaining 92,033 bovine ESTs were estimated to represent an additional 5970 genes in cattle. On average, approximately 8600 genes were estimated to be expressed in a single tissue and (or) organ and 13,000 in a pooled tissue library. On the basis of the estimated numbers of genes, no more than 3% of genes would be missed when approximately 34,000 ESTs were sequenced from a single tissue and (or) organ library and approximately 40,000 ESTs from a pooled source, respectively. Cluster analyses of the gene expression patterns among 12 single tissues and (or) organs in cattle revealed that their expression similarities would depend on physiological functions. In addition, a total of 1502 genes were identified as preferentially expressed genes in these 12 single tissues and (or) organs with LOD (logarithm of the odds, base 10) > or = 3.0. Therefore, our study provides some insights for further investigating the developmental and functional relations of various tissues and organs in mammals.

The effects of chronic ethanol consumption during early pregnancy on conceptus health and uterine function in pigs.

BACKGROUND: Maternal ethanol consumption impairs fetal health, but it is unclear if this occurs through direct actions on the conceptus or indirectly through effects on the uterus. The objective of this study was to determine if chronic ethanol consumption in swine would impair early embryonic and fetal health either through direct effects on the conceptus or indirect effects on the endometrium. METHODS: Four experiments evaluated the effects of chronic ethanol consumption during early pregnancy. Female pigs were fed either 350 ml of 95% ethanol or an isocaloric amount of dextrose at 10 to 14-hr intervals beginning on day 10 after pubertal estrus and continuing until ovariohysterectomy 11 to 35 days after mating. At the second estrus, pigs were mated to a fertile boar that did not consume alcohol. RESULTS: In experiment 1, ethanol consumption increased (p < 0.01) blood alcohol concentrations that peaked 2-3 hr after feeding. In experiment 2, ethanol was detectable in uterine flushings 2 hr after feeding on day 11 of pregnancy and was highly correlated (r = 0.989, p < 0.001) with blood alcohol concentration. In experiment 3, ethanol consumption did not affect endometrial phospholipase C activity on days 11 and 16 of pregnancy but decreased (p < 0.05) basal endometrial prostaglandin F(2alpha) production on day 16. However, ethanol consumption did not decrease the number of conceptuses on day 11 or conceptus DNA content on days 11 or 16. In experiment 4, ethanol consumption decreased (p < 0.05) fetal survival rate to 58% versus 85% in dextrose-fed controls on day 35 of pregnancy. For viable conceptuses, ethanol consumption reduced (p < 0.01) fetal weight, fetal crown-rump length, placental weight and volume of placental (chorio-allantoic + amniotic) fluid. CONCLUSION: These results indicate that chronic ethanol consumption may impair conceptus health directly or indirectly through actions upon the endometrium. Thus, the pig may be a valuable experimental model for studies on the effects of maternal alcohol consumption on conceptus development.