Student views on the introduction of anatomy teaching packages into clinical attachments.

Following the implementation of the GMC document Tomorrow's Doctors in 1993 the amount of time dedicated to anatomy in undergraduate curricula has been reduced. This has resulted in considerable disquiet among physicians and surgeons with regard to the anatomical knowledge of newly qualified doctors, and also amongst students. This study aimed to assess the perceived student need for anatomical teaching packages to support clinical attachments in the later years of the undergraduate medical curriculum. The views of two groups of students were obtained: Group A were at the beginning of their clinical attachments, whereas Group B had completed all clinical attachments and had sat the final examination. The majority of students indicated that there was a need for the development of a teaching package for anatomy (and other basic sciences) in the later stages of the undergraduate medical curriculum. A high proportion stated that the completion of these packages should be in a self-directed manner with a staff member available. There was a difference between both groups in response to the best time to offer the packages, and in the clinical areas which might be prioritized in such a development. We conclude that the vertical integration of anatomy--perhaps through clinically focused teaching packages--would be welcomed by students as part of their clinical attachments.

Survey of clinicians' attitudes to the anatomical teaching and knowledge of medical students.

There is considerable and ongoing debate surrounding the teaching of anatomy to medical students, and the anatomical knowledge of those medical students once they graduate. Few attempts have been made to gather the opinions of clinicians on this subject. A questionnaire was sent to 362 senior clinicians in hospitals affiliated to the University of Aberdeen. A total of 162 replies were received, with this sample being representative of the population of hospital consultants. Our results indicate that the majority of clinicians feel that the current anatomical education of medical students is inadequate, and below the minimum necessary for safe medical practice. There is widespread support among clinicians for more vertical integration of anatomy teaching throughout the undergraduate curriculum.

Mouse granulated metrial gland cells require contact with stromal cells to maintain viability.

Granulated metrial gland (GMG) cells differentiate in the uterine wall in pregnancy in mice but the mechanisms which control their differentiation and maintenance are unknown. In vivo, GMG cells share an intimate association with fibroblast-like stromal cells. The importance of this association has been assessed by examining the effects of withdrawal of stromal cell contact on GMG cell maintenance in vitro. When single cell suspensions of cells were prepared from mouse metrial glands there was a steady decline in numbers with days of culture but usually some remained at 7 d of culture. The ability of metrial gland cells to kill Wehi 164 target cells in 51Cr-release cytotoxicity assays was retained by cells cultured for at least 3 d. When explants of metrial gland were maintained in culture to allow GMG cell migration onto the culture flask, the attached GMG cells were lost by 1 d later. Overall, these results suggest that a juxtacrine regulatory mechanism maintains GMG cells. The rapid loss of unsupported GMG cells in culture has major implications in the design of assays to examine GMG cell function.

Rearrangement of extracellular matrix during cluster formation by human luteinising granulosa cells in culture.

Human ovarian granulosa cells were cultured on a basement membrane preparation (Matrigel) to investigate the role of extracellular matrix components in granulosa cell cluster formation. Time-lapse videomicroscopy of these cultures revealed a rapid aggregation of cells which was initiated during the first 2-4 h of culture so that by 8 h most of the granulosa cells were incorporated into clusters. Further amalgamation then occurred with the transfer of cells along 'bridges' between combining clusters. The clustering process, which was complete by about 24 h, was accompanied by reorganisation of matrix which was visualised by immunolabelling of laminin. Clustering cells appeared to gather matrix which became distributed around the clusters. Confocal microscopy showed matrix to be present over the surface of each cluster as well as around the base apparently anchoring the aggregate to the culture surface. Results suggest the potential for active rearrangement of matrix by granulosa-derived cells during corpus luteum development.

Mouse granulated metrial gland cell cytotoxicity of Wehi 164 cells: is there a role for interleukin-3 and tumour necrosis factor-alpha?

PROBLEM: Mouse granulated metrial gland (GMG) cells are maternal, cytotoxic cells found in the uterine wall in pregnancy. In vivo, they are cytotoxic to layer 1 labyrinthine placental cells. In an in vitro system, granulated metrial gland cells are highly cytotoxic to Wehi 164 fibrosarcoma cells. In this study the role of interleukin (IL)-3 and tumour necrosis factor (TNF)-alpha in granulated metrial gland cell cytotoxic activity was investigated. METHOD OF STUDY: Chromium-release cytotoxicity assays using mouse metrial gland effector cells and Wehi 164 target cells with the addition of IL-3 or an antibody to TNF-alpha. RESULTS: An antibody to TNF-alpha reduced the level of cytotoxic activity. IL-3 had no effect on the level of cytotoxicity. CONCLUSION: Mouse granulated metrial gland cells kill using a TNF-alpha mediated mechanism which is independent of IL-3 stimulation.

Effect of serum on mouse granulated metrial gland cell cytotoxicity.

PROBLEM: To examine factors affecting mouse granulated metrial gland cell cytotoxicity. METHOD OF STUDY: Chromium-release assays using mouse metrial gland cell suspensions targeted against Wehi 164 fibrosarcoma cells were used. Modulation of cellular cytotoxicity was investigated using an antibody, anti-asialo-GM1, to attempt depletion of effector cells and sera to determine if inhibitory factors are present in blood in vivo. RESULTS: No reduction in cellular cytotoxicity was found following treatment of effector cells with asialo-GM1 antibody, but there was a reduction following treatment with asialo-GM1 antibody plus guinea pig serum and with guinea pig serum alone. Sera from pregnant, male, and SCID mice also reduced the level of cytotoxicity by metrial gland cell suspensions. CONCLUSIONS: The reduction in cytotoxicity in the presence of serum indicates that there are factors in the blood which are inhibitory to granulated metrial gland cell cytotoxic activity in vivo. The resistance of mouse metrial gland cells to asialo-GM1 antibody depletion is supportive of a natural cytotoxic (NC) lineage for this cell type.

Granulated metrial gland cells and interstitial trophoblast in the uterine wall of the bank vole, Clethrionomys glareolus, in early pregnancy.

The morphology and distribution of granulated metrial gland cells and of interstitial trophoblast cells in the uterine wall was studied in the first half of pregnancy in the bank vole, Clethrionomys glareolus. The morphology and distribution of granulated metrial gland cells was generally similar to that found in other members of the Rodentia, although they were absent from the walls of the arterial vessels passing through the decidua basalis. Interstitial trophoblast invaded the decidualising endometrium mesometrial to, and antimesometrial to, the implanted embryos. There was no apparent spatiotemporal relationship between the distribution of granulated metrial gland cells and interstitial trophoblast cells.

Natural cytotoxic and antibody-dependent cellular cytotoxic activity of cells in the decidua basales and metrial glands of pseudopregnant rats with deciduomata.

Cytotoxic cells are present in the uterine wall of pregnant rats. To determine if the cytotoxic activity arises in response to semen or the products of conception, the profile of cytotoxic activity in deciduomata of pseudopregnant rats was examined. To examine NK activity, Yac-1 cells were used as targets in chromium release cytotoxicity assays and an antibody to Yac-1 cells was included in some assays to determine antibody-dependent cellular cytotoxic (ADCC) activity. Cells from the metrial glands and deciduae of deciduomata of rats at days 10 and 13 of pseudopregnancy did not show NK activity but ADCC activity was present. To examine natural cytotoxic (NC) activity, Wehi 164 cells were used as targets in chromium release cytotoxicity assays. Cells isolated from the metrial glands and deciduae of rats at day 10 of pseudopregnancy were able to kill Wehi 164 cells after 21 h assays, thus demonstrating NC activity. The profile of cytotoxic activity in the uterine wall of pseudopregnant rats with deciduomata is similar to that found in pregnancy and is thus independent of semen or the products of conception.

Granulated metrial gland cells in 'minor' species.

Granulated metrial gland cells, also known as uterine natural killer cells or large granular lymphocytes, are pregnancy associated leucocytes of granular phenotype. They are well characterised in mice and humans in terms of their structure, origin and distribution although the function of these cells has yet to be determined. In this review, granulated metrial gland cells in 'minor' species of rodents, insectivores, primates and species with epitheliochorial placentae are described. Emphasis is given to the comparative structure and distribution of granulated metrial gland cells in these minor species and to their possible functional association with trophoblast. Comparative studies of granulated metrial gland cells in minor species complements other approaches such as can be provided using mutant mice.

Experimental evidence of secretion by mouse granulated metrial gland cells.

Granulated metrial gland cells are cytotoxic cells found in the uterine wall in pregnancy. In this study, the involvement of the cytoplasmic granules of mouse granulated metrial gland cells during cytolysis of fibrosarcoma Wehi 164 cells was investigated in vitro. Using the lectin Helix pomatia agglutinin which binds to the granule membrane, but not to the cell membrane, of mouse granulated metrial gland cells, the limiting membrane of one or more cytoplasmic granules became incorporated into the cell membrane of the granulated metrial gland cells during cytolysis of Wehi 164 cells. It is concluded that this occurs during exocytosis of the contents of the granules and describes the first experimental evidence of secretion by mouse granulated metrial gland cells.

Lectin histochemical studies of mouse granulated metrial gland cells.

A lectin histochemical study has been carried out on mouse granulated metrial gland cells, the major leucocyte population that differentiates in the uterine wall in pregnancy. The binding characteristics of 26 lectins were examined using light microscopical methods. Fourteen of the lectins, with affinities ranging through N-acetylgalactosamine, galactose, N-acetylglucosamine, mannose and sialic acid residues, bound to the cytoplasmic granules of granulated metrial gland cells, and each appeared to bind to the limiting membrane of the granules. The binding characteristics of three of these lectins (Wheat germ agglutinin, Concanavalin A and Helix pomatia agglutinin) were examined using electron microscopical methods. These showed a different binding pattern to the cytoplasmic granules of granulated metrial gland cells compared with that found using light microscopical methods, as they appeared to bind evenly across the granule's matrix. This binding pattern corresponds to the reactivity of the granule matrix in the periodic acid-Schiff technique. Six lectins bound to the cell membranes of granulated metrial gland cells. These included the E and L isoforms of Phaseolus vulgaris agglutinin, with affinities for complex carbohydrates, whose binding differences were related to the stage of differentiation of the granulated metrial gland cells. The lectin binding described presents additional markers of granulated metrial gland cells and tools for investigating carbohydrate moieties in the functional activities of granulated metrial gland cells.

A study of natural cytotoxic (NC) activity in the metrial glands of rats and mice.

Cell suspensions prepared from the metrial glands of rats killed on days 10, 13 and 20 of pregnancy and mice killed on day 12 of pregnancy were assessed for their ability to kill natural cytotoxic cell target Wehi 164 cells in a 51chromium-release cytotoxicity assay. High cytotoxicity indices were found with metrial gland cell suspensions from rats killed on days 10 and 13 of pregnancy and from mice killed on day 12 of pregnancy. Cell suspensions from rats killed on day 20 of pregnancy, when there are relatively few of the granulated metrial gland cells which characterize the metrial gland, had little natural cytotoxic cell cytotoxic activity. Direct observation of mouse granulated metrial gland cells killing co-cultured Wehi 164 cells were made using time-lapse video recordings. The results indicate that granulated metrial gland cells are a type of natural cytotoxic cell.

Murine granulated metrial gland cells are susceptible to Chlamydia psittaci infection in vivo.

Granulated metrial gland (GMG) cells are the most numerous lymphoid cells in the uteroplacental unit in rodent pregnancy. In an experimental murine model of abortion-causing infection, we have studied the responses of GMG cells to Chlamydia psittaci. Chlamydial inclusions have been found within GMG cells, both in apparently healthy cells and in cells with degenerative changes. Establishing the existence of GMG cells infected by C. psittaci opens a new and interesting chapter in the study of these cells.

Antibody-dependent cellular cytotoxic activity of cells in the rat metrial gland in pregnancy.

Antibody-dependent cellular cytotoxic (ADCC) activity of cells in rat metrial glands at days 13 and 20 of pregnancy has been examined. A 51chromium-release cytotoxicity assay was carried out using Yac-1 cells and P815 cells as targets in the presence of the corresponding, heat inactivated rat antibody or non-immune rat serum. No killing was observed when effector metrial gland cells and target cells were cultured in the presence of non-immune rat serum. In the presence of rat antibody to Yac-1 cells, or rat antibody to P815 cells, cells from the metrial glands of rats killed at day 13 of pregnancy demonstrated ADCC activity, but cells from the metrial glands of rats killed at day 20 of pregnancy showed no ADCC activity. Spleen and peritoneal exudate cells displayed ADCC activity. Immunohistological and immunocytological studies showed OX-6, OX-34, OX-35 and OX-42 positive cells were present at days 13 and 20 of pregnancy, in sections of metrial glands and in the cell suspensions prepared for the cytotoxicity assays. It is suggested that macrophages are the cells most likely to be responsible for the ADCC activity in the rat metrial gland.

Granulated metrial gland cells in the uterine wall and placenta of the pregnant woodmouse, Apodemus sylvaticus.

The differentiation of the decidua and the fetal placenta in the woodmouse, Apodemus sylvaticus, was studied with particular attention to the differentiation and migration of granulated metrial gland cells. Numerous granulated metrial gland cells, characterised by their glycoprotein-containing cytoplasmic granules, were found to differentiate in the decidua basalis and metrial gland of the uterine wall during the first half of pregnancy. Many granulated metrial gland cells appeared to pass into the lumina of blood vessels in the uterine wall and reach the maternal blood spaces of the fetal placenta. In the labyrinthine placenta some granulated metrial gland cells were found associated with degenerate cytotrophoblast lining the maternal blood spaces. This finding supports previous studies of the mouse, Mus musculus, suggesting that the labyrinthine placenta is an important site for the function of the bone marrow-derived granulated metrial gland cell.

Monoclonal antibodies directed against surface and intracellular antigens of mouse granulated metrial gland cells.

Rat monoclonal antibodies with reactivity directed against mouse GMG cells have been produced. One of the antibodies (GMG-1) reacts with a surface antigen of GMG cells and cross-reacts with T lymphocytes. Another (GMG-2) reacts with an intracellular antigen in GMG cells and with asialo-GM1 positive cells in the spleen. Three antibodies (GMG-3, -4, -5) bind to intracellular antigens in GMG cells. The cross-reactivity of these antibodies is discussed with reference to the lineage relationship of GMG cells to NK cells and T cells and the recent suggestion that NK cells and T cells have a common progenitor cell. It is proposed that GMG cells share this common progenitor cell but are otherwise independent of the NK or T cell lineages.

A scanning electron microscopy study of interactions between mouse granulated metrial gland cells and placental trophoblast cells in vitro.

Mouse granulated metrial gland cells were cocultured with labyrinthine placental cells and cell-cell contacts examined by scanning electron microscopy. Intimate contacts between granulated metrial gland cells and placental cells were observed and in some of these, differences in the surface morphology of the granulated metrial gland cells were observed. Some contact areas were suggestive of the granulated metrial gland cell monitoring the surface of potential target placental trophoblast cells prior to lysis.