Sirvi Autor "Lavrits, Arina" järgi

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Individually cultured bovine embryos produce extracellular vesicles that have the potential to be used as non-invasive embryo quality markers
(2020-06) Dissanayake, Keerthie; Nõmm, Monika; Lättekivi, Freddy; Ressaissi, Yosra; Godakumara, Kasun; Lavrits, Arina; Midekessa, Getnet; Viil, Janeli; Bæk, Rikke; Møller Jørgensen, Malene; Bhattacharjee, Sourav; Aneta, Andronowska; Salumets, Andres; Jaakma, Ülle; Fazeli, Alireza
Extracellular vesicles (EVs) are membrane-bound biological nanoparticles (NPs) and have gained wide attention as potential biomarkers. We aimed to isolate and characterize EVs from media conditioned by individually cultured preimplantation bovine embryos and to assess their relationship with embryo quality. Presumptive zygotes were cultured individually in 60 μl droplets of culture media, and 50 μl of media were collected from the droplets either on day 2, 5 or 8 post-fertilization. After sampling, the embryo cultures were continued in the remaining media until day 8, and the embryo development was evaluated at day 2 (cleavage), day 5 (morula stage) and day 8 (blastocyst stage). EVs were isolated using qEVsingle® columns and characterized. Based on EV Array, EVs isolated from embryo conditioned media were strongly positive for EV-markers CD9 and CD81 and weakly positive for CD63 and Alix among others. They had a cup-like shape typical to EVs as analyzed by transmission electron microscopy and spherical shape in scanning electron microscopy, and hence regarded as EVs. However, the NPs isolated from control media were negative for EV markers. Based on nanoparticle tracking analysis, at day 2, the mean concentration of EVs isolated from media conditioned by embryos that degenerated after cleaving (8.25 × 108/ml) was higher compared to that of embryos that prospectively developed to blastocysts (5.86 × 108/ml, p < 0.05). Moreover, at day 8, the concentration of EVs isolated from media conditioned by degenerating embryos (7.17 × 108/ml) was higher compared to that of blastocysts (5.68 × 108/ml, p < 0.05). Furthermore, at day 8, the mean diameter of EVs isolated from media conditioned by degenerating embryos (153.7 nm) was smaller than EVs from media conditioned by blastocysts (163.5 nm, p < 0.05). In conclusion, individually cultured preimplantation bovine embryos secrete EVs in the culture media and their concentration and size are influenced by embryo quality and may indicate their prospective development potential.
Specific trophoblast transcripts transferred by extracellular vesicles affect gene expression in endometrial epithelial cells and may have a role in embryo-maternal crosstalk
(BioMed Central Ltd, 2019-11-14) Es-Haghi, Masoumeh; Godakumara, Kasun; Häling, Annika; Lättekivi, Freddy; Lavrits, Arina; Viil, Janeli; Andronowska, Aneta; Nafee, Tamer; James, Victoria; Jaakma, Ülle; Salumets, Andres; Fazeli, Alireza
Background. Successful establishment of pregnancy hinges on appropriate communication between the embryo and the uterus prior to implantation, but the nature of this communication remains poorly understood. Here, we tested the hypothesis that the endometrium is receptive to embryo-derived signals in the form of RNA. Methods. We have utilized a non-contact co culture system to simulate the conditions of pre implantation environment of the uterus. We bioorthogonally tagged embryonic RNA and tracked the transferred transcripts to endometrium. Transferred transcripts were separated from endometrial transcripts and sequenced. Changes in endometrial transcripts were quantified using quantitative PCR. Results. We show that three specific transcripts are transferred to endometrial cells. We subsequently demonstrate a role of extracellular vesicles (EVs) in this process, as EVs obtained from cultured trophoblast spheroids incubated with endometrial cells induced down-regulation of all the three identified transcripts in endometrial cells. Finally, we show that EVs/nanoparticles captured from conditioned culture media of viable embryos as opposed to degenerating embryos induce ZNF81 down-regulation in endometrial cells, hinting at the functional importance of this intercellular communication. Conclusion. Ultimately, our findings demonstrate the existence of an RNA-based communication which may be of critical importance for the establishment of pregnancy.
Trofoblasti rakuliini HTR-8/SVneo mikrovesiikulite ja eksosoomide sisenemine endomeetriumi rakuliinide RL95-2 ja HEC-1A rakkudesse
(Tartu Ülikool, 2016) Lavrits, Arina; Ingerpuu, Sulev; Koel, Mariann; Tartu Ülikool. Loodus- ja tehnoloogiateaduskond; Tartu Ülikool. Molekulaar- ja rakubioloogia instituut
Nii retseptoorse kui ka mitteretseptoorse endomeetriumi kartsinoomi rakuliinide rakud võtavad sisse trofoblasti rakuliini HTR8/SVneo rakkudest pärit mikrovesiikuleid ja eksosoome, kusjuures HEC-1A rakkudesse mikrovesiikulid sisenevad põhimõtteliselt makropinotsütoosi ja klatriin-vahendatud endotsütoosi teel. RL95-2 rakkude kohta ei saa praegu öelda, mis mehhanismi mikrovesiikulid kasutavad rakkudesse sisenemiseks. Kuid kuivõrd tegemist on kasvajaliste rakkudega, siis ei ole saadud tulemuste põhjal võimalik öelda, kas see kehtib ka normaalsete rakkude puhul. Edasises töös tuleb siiski arvestada, et normaalsete trofoblastide ja endomeetriumirakkude kasvatamine on väga keeruline ning siiani puuduvad andmed kuivõrd efektiivselt toimub nendest rakkudest vesiikulite sekreteerimine.
Trofoblasti rakuliini JAR rakkude poolt toodetud lamininide 111 ja 511 sekretsioon ning rakuvälise maatrikis moodustamine
(Tartu Ülikool, 2014-06-13) Lavrits, Arina; Ingerpuu, Sulev, juhendaja; Tartu Ülikool. Loodus- ja tehnoloogiateaduskond; Tartu Ülikool. Molekulaar- ja rakubioloogia instituut