Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0268596 (EMA)
 2,520 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The temporal and spatial pattern of segregation of the avian germline from the formation of the area pellucida to the beginning of primitive streak formation (stages VII-XIV, EG&K) was investigated using the culture of whole embryos and central and peripheral embryo fragments on vitelline membranes at stages VII-IX, immunohistological analysis of whole mount embryos and sections with monoclonal antibodies MC-480 against stage-specific embryonic antigen-1 (SSEA-1) and EMA-1, and with the culture of dispersed blastoderms at stages IX-XIV with and without on STO feeder layer. Whole embryos at intrauterine stages developed up to the formation of the primitive streak despite the absence of area pellucida expansion. Primordial germ cells (PGCs) appeared in the cultures of whole embryos and only in central fragments containing a partially formed area pellucida at stages VII-IX. When individual stage IX-XIV embryos were dispersed and cultured without a feeder layer, 25-45 PGCs/embryo were detected only with stage X-XIV, but not with stage IX blastoderms. However, the culture of dispersed cells from the area pellucida of stages IX-XIII on STO feeder layers yielded about 150 PGCs/embryo. The carbohydrate epitopes recognized by anti-SSEA-1 and EMA-1 first appeared at stage X on cells in association with polyingressing cells on the ventral surface of the epiblast and later on the dorsal surface of the hypoblast. The SSEA-1-positive hypoblast cells gave rise to chicken PGCs when cultured on a feeder layer of quail blastodermal cells. From these observations, we propose that the segregation and development of avian germline is a gradual, epigenetic process associated with the translocation of SSEA-1/EMA-1-positive cells from the ventral surface of the area pellucida at stage X to the dorsal side of the hypoblast at stages XI-XIV.
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PMID:Origin of primordial germ cells in the prestreak chick embryo. 902 82

Monoclonal antibodies anti-SSEA-1 and EMA-1, and the lectins DBA and LTA, bound to the surface of large, round cells randomly distributed in the 26-day pig genital ridge. Other antibodies, SSEA-3, SSEA-4, TRA-1-60, and TRA-1-81, did not react with any cells in the pig genital ridge. SSEA-1-positive cells displayed pseudopods and appeared to migrate from the dorsal mesentery of the hindgut (18-day) to the primordium of the gonad (day 23) and entered the genital ridge by 26 days. The number of SSEA-1-positive cells associated with the dorsal mesentery and genital ridge markedly increased from the 18-day to the 26-day pig embryo. It was concluded that the SSEA-1-positive cells were primordial germ cells (PGCs). Using these markers and alkaline phosphatase histochemistry, pig PGCs derived from the 26-day genital ridge showed no proliferation when grown in STO co-culture in the presence of human LIF, bFGF and SCF.
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PMID:Identification of pig primordial germ cells by immunocytochemistry and lectin binding. 909 3

While the culture and identification of primordial germ cells (PGCs) in mice is established, only limited investigations on PGCs in livestock have been reported. This study was performed to characterize goat PGCs after culture and cryopreservation. Goat PGCs were isolated from Day 32 fetuses and cultured on a continuous cell line of murine embryonal fibroblasts (STO) as feeder-cells in the presence of leukemia inhibitory factor (LIF). The PGCs proliferated slowly and showed colony formation in early passages. Frozen-thawed PGCs continued to proliferate when stem cell factor (SCF) was added to the culture medium. However, differentiation into epithelial-like polygonal cells or neuronal cells was observed after 1 or 2 passages. The PGCs of 1 female and 1 male cell line were characterized by immunocytochemistry. The PGCs showed positive staining for anti stage-specific embryonic antigen-1 (SSEA-1) and FMA-1 (monoclonal antibody produced against a glycoprotein cell surface antigen of the embryonal carcinoma Nulli SCC1), whereas the reactivity to alkaline phosphatase (AP), an established marker for PGCs in mice, was inconsistent. After differentiation, PGCs lost their positive reaction to SSEA-1, EMA-1 and AP. In conclusion, SSEA-1 and EMA-1 can be used as reliable markers for identifying goat PGCs in addition to morphological criteria. The results indicate that goat PGCs can be kept in long-term culture without losing their morphological characteristics and their positive reaction to SSEA-1 and EMA-1, thus providing a promising source of donor-karyoplasts for nuclear transfer procedures.
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PMID:Long-term culture and characterization of goat primordial germ cells. 1079 85