The structure and differentiation of granulated metrial gland cells of the pregnant mouse uterus

Summary A study was made with the light and electron microscopes of the granulated metrial gland cells of the decidua basalis of the pregnant mouse uterus, up to day 11 of pregnancy. The granulated metrial gland cells are large, up to 50 in diameter, mono- or binucleate and the glycogen rich cytoplasm typically contains many large glycoprotein granules which may be up to 5 in diameter. Morphological evidence is described in support of a lymphocyte-like cell being the precursor to the granulated metrial gland cell. This differentiation sequence is similar to that already proposed in the rat but differences between the ultrastructure of the mature metrial gland cells of rats and mice were noted.     

The demonstration of cells bearing Fc receptors in the metrial gland of the pregnant rat uterus

Summary Cells obtained by collagenase treatment of metrial gland tissue from rats of day 12, 13, 14 and 15 of pregnancy were examined for the presence of surface membrane receptors for immunoglobulin (Fc receptors). Using an EA rosetting technique in which sheep red blood cells (SRBC) were sensitized with a rabbit anti-SRBC immunoglobulin preparation, Fc receptors were found on a proportion of the cells. The majority of the granulated metrial gland cells were not included in the rosetting cell population, suggesting that they do not possess the type of Fc receptor detected by this method. A comparison was made between results obtained when cells were counted in suspension and those obtained from cell counts on sections of fixed material. Both methods were found to yield similar results. Acknowledgements. Our thanks are due to Dr. A.E. Wild for his generous help, both in advice and in provision of immunoglobulins and immunoglobulin fractions, to Professor D. Bulmer and Dr. S. Peel for their continued help and advice, and to the Wellcome Trust for financial support.     

Migration of granulated metrial gland cells from cultured explants of mouse metrial gland tissue

Summary The migration of granulated metrial gland (GMG) cells from cultured explants of metrial gland tissue obtained from mice killed between days 10 and 16 of pregnancy has been studied. GMG cells migrated from all of the explants but more GMG cells were found around explants obtained from mice at day 10 of pregnancy than around explants obtained at later stages of pregnancy. The number of GMG cells found around each explant reached a peak at days 1, 2 or 3 of culture but only a few GMG cells were found around the explants by day 7 of culture.     

Granulated metrial gland cells in the pregnant uterus of mice expressing the collagen mutation tight-skin (Tsk/+)

Summary Influences of the extracellular matrix (ECM) on the differentiation and distribution of granulated metrial gland (GMG) cells, a uterine natural killer (NK)-like cell subset, were studied by histological examination of implantation sites in the mouse mutant Tsk/+. Tsk/+ mice overproduce collagens I and III. GMG cell differentiation appeared to progress normally in Tsk/+ mice between days 6.5 and 12.5 of gestation. The distribution of GMG cells, however, was abnormal. Significant numbers of GMG cells were found in the antimesometrial and lateral decidual regions at day 8.5 of gestation and in the regions between implantation sites until day 10.5 of gestation. Loss of GMG cells from these regions normally occurs by day 6.5 of gestation. These data suggest that alterations to the ECM change the migration properties or life span of GMG cells.     

Expression of leucocyte antigens by cells from the metrial gland of the pregnant rat

Summary The function of the metrial gland of the rat, and particularly of its characteristic population of granulated cells, remains unknown. However, several lines of evidence suggest that the granulated cells may derive from lymphocytes, and play a role in the immunology of pregnancy. In this study, antigen expression by granulated and other cell populations from the metrial glands of rats at Days 13 and 14 of pregnancy was studied by an indirect immunoperoxidase method. Acetone-fixed frozen sections, and cytocentrifuge preparations of collagenase-dispersed metrial gland tissue in which numbers of granulated cells had been increased by density-gradient centrifugation, were used. The primary antibodies used recognised, inter alia, B lymphocytes (MRC OX-3, MRC OX-6, MRC OX-12), T lymphocytes (MRC OX-8, W3/25, MRC OX-19), neutrophils (MRC OX-42) and cells of the monocyte/macrophage series (MRC OX-3, MRC OX-6, MRC OX-42, MRC OX43). The majority of the granulated cells, including smaller, immature forms, were unlabelled by any of these antibodies. Some lymphocytes, and varying numbers of larger, non-granulated cells, were labelled by OX-6, OX-12, W3/ 25, OX-42 and OX-43. In addition to lymphocytes, labelled cells included neutrophils (OX-42), endothelial cells (OX-43), and probably some macrophages (OX-6, OX-43). OX-12, which recognises the kappa chain of rat IgG, labelled some large cells which may have been stromal cells. These findings do not support the concept that the granulated cells are derived from lymphocytes.     

The distribution and structure of cells in the tracheal epithelium of the mouse

Summary The tracheal epithelium of the mouse is a single layer of columnar cells resting on a basement membrane. Many of the cell types resemble those of other species. However, goblet cells are rare and ciliated cells occur only in scattered patches. Submucosal glands are absent from all but the highest reaches of the airway.The major proportion of the epithelial cells are non-ciliated. These usually project into the lumen of the trachea. Large amounts of smooth endoplasmic reticulum and many secretory vesicles occur within the cytoplasm. Secretory activity of these cells may be either apocrine or merocrine and these cells may transform into other cell types.It is suggested that these non-ciliated cells are Clara cells and that the mouse tracheal epithelium may make a useful model for the study of this type of cell.     

Granulated metrial gland cells of pregnant mouse uterus are natural killer-like cells that contain perforin and serine esterases

The mouse uterus during pregnancy contains a large population of lymphoid cells termed granulated metrial gland (GMG) cells. Our observations suggest that these cells are highly activated cytolytic lymphocytes related to NK or lymphokine-activated killer cells. Immunostaining demonstrated asialo GM1 and Thy-1 on GMG cells, both of which are expressed by NK cells. Decidua basalis tissue and isolated GMG cells contained three proteins that are characteristic of activated cytolytic lymphocyte granules: perforin, serine esterase 1, and serine esterase 2. These mediators were demonstrated in GMG cells by Western blot analysis using polyclonal antisera and by Northern blot analysis using specific cDNA probes for their mRNA. The proteins were not detected in normal spleen or liver or in asialo GM1+ cells isolated from those organs, consistent with the absence of these mediators from resting cytolytic cells. The amount of perforin in GMG cells was similar to that present in cloned, IL-2-stimulated, CTL shown previously to contain a large amount of this protein. A large population of NK cells bearing the surface marker LGL-1 was demonstrated at the implantation site by labeling with monoclonal antibody 4D11, but T cells were not detected. Many LGL-1+ cells at the implantation site expressed the GMG cell markers asialo GM1, Thy-1, and perforin. Staining intensities were inversely correlated, with LGL-1-bright cells showing little or no staining of GMG cell markers and LGL-1-faint cells showing more obvious staining of GMG cell markers. This suggests that LGL-1+ NK cells may differentiate in situ to GMG cells, losing LGL-1 and gaining a high concentration of GMG cell markers in the process. Activated cytolytic cells related to NK or lymphokine-activated killer cells may function in the pregnant rodent uterus to intercept and kill aberrant placental or embryonic cells that might otherwise enter the female and proliferate.     

Growth and differentiation of progenitor/stem cells derived from the human mammary gland

Estrogen is necessary for the full development of the mammary gland and it is also involved in breast cancer development. We set out to identify and characterise progenitor/stem cells in the human mammary gland and to explore the role of estrogen in their proliferation and differentiation. Three candidate stem cell populations were isolated: double positive (DP) cells co-expressed the luminal and myoepithelial markers, EMA and CALLA, respectively, whereas double negative (DN) cells did not express these cell surface markers; side population (SP) cells were characterised by their differential ability to efflux the dye Hoechst 33342. The ABC transporter, breast cancer resistance protein (BCRP) was more highly expressed in SP cells than in non-SP cells and a specific BCRP inhibitor, Ko143, reduced SP formation, suggesting that BCRP confers the SP phenotype in mammary epithelial cells, as has been demonstrated in other tissues. Interestingly, SP cells were double negative for the EMA and CALLA antigens and therefore represent a separate and distinct population to DP cells. Single cell multiplex RT-PCR indicated that the SP and DN cells do not express detectable levels of ERalpha or ERbeta, suggesting that estrogen is not involved in their proliferation. DP cells expressed ERalpha but at a lower level than differentiated luminal cells. These findings invoke a potential strategy for the breast stem/progenitor cells to ignore the mitogenic effects of estrogen. All three cell populations generated mixed colonies containing both luminal and myoepithelial cells from a single cell and therefore represent candidate multipotent stem cells. However, DN cells predominately generated luminal colonies and exhibited a much higher cloning efficiency than differentiated luminal cells. Further characterisation of these candidate progenitor/stem cells should contribute to a better understanding of normal mammary gland development and breast tumorigenesis.     

Thyroxine accelerates the differentiation of granular convoluted tubule cells and the appearance of epidermal growth factor in the submandibular gland of the neonatal mouse

Summary The effects of the administration of thyroxine (T4) on the postnatal cytodifferentiation of granular convoluted tubule (GCT) cells of the submandibular gland (SMG) of Lewiss-Webster mice were studied by light and electron microscopy. From birth, mice of both sexes were injected daily with T4 (sc 0.4 g/g BW) and were sacrificed 24 h after the last injection at 7, 9, 11, 14 and 21 days of age. Control mice received vehicle only. In control mice, granulated striated duct (SD) cells were first detected at 9 days and 7 days of age by light- and electron microscopy, respectively. Furthermore, a few scattered granulated SD cells were observed by light microscopy as early as day 7 in T4-treated mice of both sexes. At 21 days of age, in mice given T4, GCT cells were larger and more numerous and the Golgi apparatus, rough endoplasmic reticulum, and secretion granules were more abundant. In control mice, immunocytochemical staining for epidermal growth factor-(EGF) was first detectable at day 21 at the light- and electron-microscopic levels. However, positively stained cells were first observed in T4-treated mice by light- and electron-microscopic immunocytochemistry at 14 and 11 days of age, respectively. Moreover, in the 21-day-old T4-treated mice, the number of immunoreactive GCT cells, as well as the intensity of the staining per cell, was markedly increased as compared to controls. EGF immunostaining was restricted to GCT cells, and by immuno-electron-microscopy was only seen in apical secretory granules in granulated SD cells and GCT cells. There were no sex differences in the differentiation of the duct system under any conditions. It is concluded that T4 stimulates the biosynthesis of EGF by an acceleration of the differentiation of the GCT precursor cells to mature cells.Supported in part by grant no. MT-5730 from the Medical Research Council of CanadaHolder of a fellowship from the Medical Research Council of CanadaScholar of the Fonds de la Recherche en Santé du Québec     

Role of gangliosides in the differentiation of human mesenchymal-derived stem cells into osteoblasts and neuronal cells

Gangliosides are complex glycosphingolipids that are the major component of cytoplasmic cell membranes, and play a role in the control of biological processes. Human mesenchymal stem cells (hMSCs) have received considerable attention as alternative sources of adult stem cells because of their potential to differentiate into multiple cell lineages. In this study, we focus on various functional roles of gangliosides in the differentiation of hMSCs into osteoblasts or neuronal cells. A relationship between gangliosides and epidermal growth factor receptor (EGFR) activation during osteoblastic differentiation of hMSCs was observed, and the gangliosides may play a major role in the regulation of the differentiation. The roles of gangliosides in osteoblast differentiation are dependent on the origin of hMSCs. The reduction of ganglioside biosynthesis inhibited the neuronal differentiation of hMSCs during an early stage of the differentiation process, and the ganglioside expression can be used as a marker for the identification of neuronal differentiation from hMSCs. [BMB Reports 2013; 46(11): 527-532]     

Iodide transport in isolated cells of mouse submaxillary gland

A method has been developed to isolate cells from the submaxillary gland of mouse by treatment with pronase. Three fractions of cells have been isolated having almost equal iodide concentrating activity. The isolated cells show time dependent uphill transport of iodide. The transport is substrate-saturable, having aK _m value of 0.3 μM for iodide. The transport is sensitive to antithyroid drugs, metabolic inhibitors and to some extent to ouabain. Pseudohalide such as thiocyanate competes with the transport of iodide. Thyroid hormones or thyroid stimulating hormone have no significant effect on the iodide transport in these cells.     

Time course of the differentiation of granulated metrial gland cells in chimeric mice

Granulated metrial gland (GMG) cell differentiation was examined in deciduomata in lethally irradiated mice which had been reconstituted with rat bone marrow. The time at which the bone marrow reconstitution was carried out was varied in relation to the time of initiating the decidual reaction. GMG cells were examined at various times after bone marrow transplantation to determine whether they had the morphology which characterised them as being derived from host or donor stem cells. Differentiation of donor type GMG cells was seen within the first week after transplantation and occurred even when the bone marrow was transplanted two days after initiating the decidual response.     

Quantitative changes in the frequency and distribution of the C-cell population in the rat thyroid gland with age

Summary The development of calcitonin cells (C-cells) was investigated in rat thyroid glands from birth to 120 days, using an immunoperoxidase technique and a point-counting method. The proportion of C-cells to follicular cells was 4.5% on the day of birth and increased progressively to 10.4% by 120 days. The highest density of C-cells was noted in the mid-region of the lobes along a longitudinal axis. The caudal and cephalic regions of the lobes contained smaller numbers of C-cells. The C-cells tended to be more numerous in the posterior aspects of the lobes. Although the numbers of C-cells in 120-day-old animals were markedly increased as compared to animals at the time of birth, the cell distributions within the glands were similar at all ages.     

The structure and distribution of satellite cells of cardiac muscles in decapod crustaceans

Summary The structure and distribution of satellite cells of cardiac muscles were examined in twenty-one species of animals chosen from each tribe within the order Decapoda (Arthropoda, Crustacea). The satellite cells were found in all animals observed. Most of them are morphologically identical with those described in different striated muscles of other species, but some cells have unusual features. The decapod satellite cell occasionally lies right over the region corresponding to the intercalated disc between the apposed cardiac muscle cells. The cell sends cytoplasmic processes into the adjacent muscle cells, enabling the plasma membrane to make close contact with the cleft opening of the intercalated disc, and with the myofibril at the level of the Z-line. Another characteristic feature is the presence of paired cells. Such cells are clearly separated from each other over most of the contact area by the respective plasma membranes, which are smooth in appearance and devoid of specialized regions. The significance of the presence of satellite cells in decapod cardiac muscle and its possible role are discussed and compared with those described for other species.     

Structure and innervation of the pineal gland of the rabbit,Oryctolagus cuniculus (L.)

Summary A light microscopic investigation of the rabbit pineal gland with the aid of silver-stained sections gave the following results. In the gland a medulla and a cortex can be distinguished, the medulla containing so-called light and dark pinealocytes, the cortex only light ones. Autonomic nerve fibres reach the pineal organ by two routes: (1) via the perivascular spaces of pineal blood vessels and (2) via two distinct nerve bundles, the nervi conarii. Bilateral superior cervical ganglionectomy revealed that these pinealo-petal nerve fibres are mainly orthosympathetic postganglionic. Intramural pineal neurones with synaptic-like structures on their cell bodies and dendrites point to the presence of a parasympathetic innervation next to the orthosympathetic one. Direct afferent or efferent neural connections with the brain appeared to be absent. Acknowledgements. The author wishes to thank Professor Dr. J. Ariëns Kappers for encouragement and help, Mr. H. K. Koerten for his technical assistance and Miss A. M. Feddema for typing the manuscipt.     

Identification of stage-specific markers during differentiation of hair cells from mouse inner ear stem cells or progenitor cells in vitro

The induction of inner ear hair cells from stem cells or progenitor cells in the inner ear proceeds through a committed inner ear sensory progenitor cell stage prior to hair cell differentiation. To increase the efficacy of inducing inner ear hair cell differentiation from the stem cells or progenitor cells, it is essential to identify comprehensive markers for the stem cells/progenitor cells from the inner ear, the committed inner ear sensory progenitor cells and the differentiating hair cells to optimize induction conditions. Here, we report that we efficiently isolated and expanded the stem cells or progenitor cells from postnatal mouse cochleae, and induced the generation of inner ear progenitor cells and subsequent differentiation of hair cells. We profiled the gene expression of the stem cells or progenitor cells, the inner ear progenitor cells, and hair cells using aRNA microarray analysis. The pathway and gene ontology (GO) analysis of differentially expressed genes was performed. Analysis of genes exclusively detected in one particular cellular population revealed 30, 38, and 31 genes specific for inner ear stem cells, inner ear progenitor cells, and hair cells, respectively. We further examined the expression of these genes in vivo and determined that Gdf10+Ccdc121, Tmprss9+Orm1, and Chrna9+Espnl are marker genes specific for inner ear stem cells, inner ear progenitor cells, and differentiating hair cells, respectively. The identification of these marker genes will likely help the effort to increase the efficacy of hair cell induction from the stem cells or progenitor cells.     

Inefficient processing of human protein C in the mouse mammary gland

Vitamin K-dependent plasma protein, human Protein C (HPC) has been expressed in transgenic mice, using a 4.2kb mouse whey acidic protein (WAP) promoter, 9.0 kb HPC gene and 0.4 kb 3flanking sequences. Expression was mammary gland-specific and the recombinant human Protein C (rHPC) was detected in milk at concentrations of 0.1 to 0.7mg ml^–1. SDS-PAGE revealed that the single, heavy and light chains of rHPC migrated with increased electrophoretic mobility, as compared to HPC. Enzymatic deglycosylation showed that these molecular weight disparities are in part due to differential glycosylation. The substantial increase observed in the amount of single chain protein, as well as the presence of the propeptide attached to 20–30% of rHPC, suggest that mouse mammary epithelial cells are not capable of efficient proteolytic processing of rHPC. TheK _m of purified rHPC for the S-2366 synthetic substrate was similar to that of plasma-derived HPC, while the specific activity was about 42–77%. Amino acid sequence analyses and low anticoagulant activity of purified rHPC suggest that -carboxylation of rHPC is insufficient. These results show that proteolytic processing and -carboxylation can be limiting events in the overexpression of fully biologically active rHPC in the mouse mammary gland.