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Ali Honaramooz - One of the best experts on this subject based on the ideXlab platform.
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Validation of ultrasound biomicroscopy for the assessment of xenogeneic Testis Tissue grafts and cell implants in recipient mice.
Andrology, 2020Co-Authors: Mohammad Amin Fayaz, Awang Hazmi Awang-junaidi, Jaswant Singh, Ali HonaramoozAbstract:BACKGROUND Subcutaneous grafting/implantation of neonatal Testis Tissue/cells from diverse donor species into recipient mice can be used as an in vivo model to study Testis development, spermatogenesis, and steroidogenesis. Ultrasound biomicroscopy (UBM) allows obtaining high definition cross-sectional images of Tissues at microscopic resolutions. OBJECTIVES The present study was designed to (a) validate the use of UBM for non-invasive monitoring of grafts/implants overtime and to (b) correlate UBM findings with the morphological attributes of recovered grafts/implants. MATERIALS AND METHODS Testis Tissue fragments (~14 mm3 , each) and cell aggregates (100 × 106 cells, each) obtained from 1-week-old donor piglets (n = 30) were grafted/implanted under the back skin of immunodeficient mice (n = 6) in eight analogous sites per mouse. Three-dimensional transcutaneous Doppler UBM was performed, and a randomly selected graft and its corresponding implant were recovered at 2, 4, 6, and 8 weeks. RESULTS Graft/implant weight (P = .04) and physical height (P = .03) increased overtime. The dynamics of physical length and volume increases over time differed between Tissue grafts and cell implants (P = .02 and 0.01 for sample type*time interactions, respectively). UBM-estimated volume was correlated with the post-recovery weight and volume of the grafts/implants (r = 0.98 and r = 0.99, respectively; P
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validation of ultrasound biomicroscopy for the assessment of xenogeneic Testis Tissue grafts and cell implants in recipient mice
Journal of Andrology, 2020Co-Authors: Mohammad Amin Fayaz, Jaswant Singh, Awang Hazmi Awangjunaidi, Ali HonaramoozAbstract:BACKGROUND Subcutaneous grafting/implantation of neonatal Testis Tissue/cells from diverse donor species into recipient mice can be used as an in vivo model to study Testis development, spermatogenesis, and steroidogenesis. Ultrasound biomicroscopy (UBM) allows obtaining high definition cross-sectional images of Tissues at microscopic resolutions. OBJECTIVES The present study was designed to (a) validate the use of UBM for non-invasive monitoring of grafts/implants overtime and to (b) correlate UBM findings with the morphological attributes of recovered grafts/implants. MATERIALS AND METHODS Testis Tissue fragments (~14 mm3 , each) and cell aggregates (100 × 106 cells, each) obtained from 1-week-old donor piglets (n = 30) were grafted/implanted under the back skin of immunodeficient mice (n = 6) in eight analogous sites per mouse. Three-dimensional transcutaneous Doppler UBM was performed, and a randomly selected graft and its corresponding implant were recovered at 2, 4, 6, and 8 weeks. RESULTS Graft/implant weight (P = .04) and physical height (P = .03) increased overtime. The dynamics of physical length and volume increases over time differed between Tissue grafts and cell implants (P = .02 and 0.01 for sample type*time interactions, respectively). UBM-estimated volume was correlated with the post-recovery weight and volume of the grafts/implants (r = 0.98 and r = 0.99, respectively; P < .001). Pre- and post-recovery length and height of the grafts/implants were positively and strongly correlated (r = 0.50, P = .01; r = 0.70, P = .001) and so were the areas covered by cordal, non-cordal, or fluid-filled cavities between UBM and histology (r = 0.87, P < .001). DISCUSSION AND CONCLUSION UBM findings correlated with physical attributes of the grafts/implants, validating its use as a non-invasive high-fidelity tool to quantify the developmental changes in ectopic Testis Tissue grafts and cell implants, potentially leading to a reduction in the number of recipient mice needed for similar experiments.
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Regeneration of Testis Tissue after ectopic implantation of porcine Testis cell aggregates in mice: improved consistency of outcomes and in situ monitoring
Reproduction fertility and development, 2020Co-Authors: Awang Hazmi Awang-junaidi, Jaswant Singh, Ali HonaramoozAbstract:Ectopic implantation of donor Testis cell aggregates in recipient mice results in de novo formation or regeneration of Testis Tissue and, as such, provides a unique invivo model for the study of Testis development. However, currently the results are inconsistent and the efficiency of the model remains low. This study was designed to: (1) examine several factors that can potentially improve the consistency and efficiency of this model and (2) explore the use of ultrasound biomicroscopy (UBM) for the non-invasive invivo evaluation of implants. Testis cell aggregates, containing ~40% gonocytes, from 1-week-old donor piglets were implanted under the back skin of immunodeficient mice through skin incisions using gel matrices or through subcutaneous injection without using gel matrices. The addition of gel matrices led to inconsistent Tissue development; gelatin had the greatest development, followed by collagen, whereas agarose resulted in poor development. The results also depended on the implanted cell numbers since implants with 100×106 cells were larger than those with 50×106 cells. The injection approach for cell implantation was less invasive and resulted in more consistent and efficient Testis Tissue development. UBM provided promising results as a means of non-invasive monitoring of implants.
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Feasibility of salvaging genetic potential of post-mortem fawns: production of sperm in Testis Tissue xenografts from immature donor white-tailed deer (Odocoileus virginianus) in recipient mice.
Animal reproduction science, 2012Co-Authors: Sepideh Abbasi, Ali HonaramoozAbstract:The purpose of this study was to evaluate the long-term outcome of Testis Tissue xenografting from immature deer. Testis Tissue was collected post-mortem from a 2-mo-old white-tailed deer fawn (Odocoileus virginianus) and small fragments of the Tissue were grafted under the back skin of immunodeficient recipient mice (n = 7 mice; 8 fragments/mouse). Single xenograft samples were removed from representative recipient mice every 2 mo from grafting for up to 14 mo post-grafting. The retrieved xenografts were evaluated for seminiferous tubular density (per mm(2)) and tubular diameter, as well as for seminiferous tubular morphology and identification of the most advanced germ cell type present in each tubule cross section. Overall, 63% of the grafted Testis fragments were recovered as xenografts. Testis Tissue xenografts showed a gradual testicular development starting with tubular expansion by 2 mo, presence of spermatocytes by 6 mo post-grafting, round and elongated spermatids by 8 mo, followed by fully-formed sperm by 12 mo post-grafting. The timing of complete spermatogenesis generally corresponded to the reported timing of sexual maturation in white-tailed deer. This study demonstrated, for the first time, that Testis Tissue xenografting from immature deer donors into recipient mice can successfully result in testicular maturation and development of spermatogenesis in the grafts up to the stage of sperm production. These results may therefore provide a model for salvaging genetic material from immature male white-tailed deer that die before reaching sexual maturity.
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Characterization and quenching of autofluorescence in piglet Testis Tissue and cells.
Anatomy research international, 2012Co-Authors: Yanfei Yang, Ali HonaramoozAbstract:Significant intrinsic fluorescence in Tissues and in disassociated cells can interfere with fluorescence identification of target cells. The objectives of the present study were (1) to examine an intrinsic fluorescence we observed in both the piglet Testis Tissue and cells and (2) to test an effective method to block the autofluorescence. We observed that a number of granules within the Testis interstitial cells were inherently fluorescent, detectable using epifluorescence microscopy, confocal laser scanning microscopy, and flow cytometry. The emission wavelength of the autofluorescent substance ranged from 425 to 700 nm, a range sufficiently broad that could potentially interfere with fluorescence techniques. When we treated the samples with Sudan Black B for different incubation times, the intrinsic fluorescence was completely masked after treatment for 10–15 min of the Testis Tissue sections or for 8 min of the Testis cells, without compromising specific fluorescence labeling of gonocytes with lectin Dolichos biflorus agglutinin (DBA). We speculate that the lipofuscin or lipofuscin-like pigments within Leydig cell granules were mainly responsible for the observed intrinsic fluorescence in piglet testes. The method described in the present study can facilitate the identification and characterization of piglet gonocytes using fluorescence microscopy.
Ina Dobrinski - One of the best experts on this subject based on the ideXlab platform.
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germ cell survival and differentiation after xenotransplantation of Testis Tissue from three endangered species iberian lynx lynx pardinus cuvier s gazelle gazella cuvieri and mohor gazelle g dama mhorr
Reproduction Fertility and Development, 2014Co-Authors: Lucía Arregui, Ina Dobrinski, Eduardo R S RoldanAbstract:The use of assisted reproductive techniques for endangered species is a major goal for conservation. One of these techniques, Testis Tissue xenografting, allows for the development of spermatozoa from animals that die before reaching sexual maturity. To assess the potential use of this technique with endangered species, Testis Tissue from six Iberian lynxes (one fetus, two perinatal cubs, two 6-month-old and one 2-year-old lynx), two Cuvier's gazelle fetuses and one 8-month-old Mohor gazelle were transplanted ectopically into nude mice. Tissue from the lynx fetus, perinatal cubs and 2-year-old donors degenerated, whereas spermatogonia were present in 15% of seminiferous tubules more than 70 weeks after grafting in transplanted Testis Tissue from 6-month-old donors. Seminal vesicle weights (indicative of testosterone production) increased over time in mice transplanted with Tissue from 6-month-old lynxes. Progression of spermatogenesis was observed in xenografts from gazelles and was donor age dependent. Tissue from Cuvier's gazelle fetuses contained spermatocytes 40 weeks after grafting. Finally, round spermatids were found 28 weeks after transplantation in grafts from the 8-month-old Mohor gazelle. This is the first time that xenotransplantation of testicular Tissue has been performed with an endangered felid and the first successful xenotransplantation in an endangered species. Our results open important options for the preservation of biological diversity. Additional keywords: conservation, testicular Tissue, threatened species, xenografting.
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De novo morphogenesis of Testis Tissue: an improved bioassay to investigate the role of VEGF165 during Testis formation
Reproduction (Cambridge England), 2014Co-Authors: Camila Dores, Ina DobrinskiAbstract:De novo formation of Testis Tissue from single-cell suspensions allows manipulation of different testicular compartments before grafting to study testicular development and the spermatogonial stem cell niche. However, the low percentages of newly formed seminiferous tubules supporting complete spermatogenesis and lack of a defined protocol have limited the use of this bioassay. Low spermatogenic efficiency in de novo formed Tissue could result from the scarcity of germ cells in the donor cell suspension, cell damage caused by handling or from hypoxia during Tissue formation in the host environment. In this study, we compared different proportions of spermatogonia in the donor cell suspension and the use of Matrigel as a scaffold to support de novo Tissue formation and spermatogenesis. Then, we used the system to investigate the role of vascular endothelial growth factor 165 (VEGF165) during testicular morphogenesis on blood vessel and seminiferous tubule formation, and on presence of germ cells in the de novo developed tubules. Our results show that donor cell pellets with 10×10(6) porcine neonatal testicular cells in Matrigel efficiently formed Testis Tissue de novo. Contrary to what was expected, the enrichment of the cell suspension with germ cells did not result in higher numbers of tubules supporting spermatogenesis. The addition of VEGF165 did not improve blood vessel or tubule formation, but it enhanced the number of tubules containing spermatogonia. These results indicate that spermatogenic efficiency was improved by the addition of Matrigel, and that VEGF165 may have a protective role supporting germ cell establishment in their niche.
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endocrine modulation of the recipient environment affects development of bovine Testis Tissue ectopically grafted in mice
Reproduction, 2012Co-Authors: Jose R Rodriguezsosa, Rahul Rathi, Guilherme Mj Costa, Luiz R Franca, Ina DobrinskiAbstract:Testis Tissue xenografting is a powerful approach for the study of Testis development and spermatogenesis, and for fertility preservation in immature individuals. In bovine Testis xenografts, maturation and spermatogenesis are inefficient when compared to other species. To evaluate if exogenous modulation of the endocrine milieu in recipient mice will affect spermatogenic efficiency in xenografts from newborn calves, recipient mice were treated with the GnRH antagonist acyline (5 mg/kg s.c. every 2 weeks) to reduce testosterone production in xenografts, or with 6-N-propyl-2-thiouracil (PTU, 0.1% in drinking water for 4 weeks), to induce transient hypothyroidism in recipient mice respectively. Both treatments altered developmental parameters of Testis xenografts and reduced germ cell differentiation. While the effects of acyline treatment can be attributed to inhibition of GnRH and gonadotropin action, lower Sertoli cell numbers and decreased seminiferous tubule length observed after PTU treatment were opposite to effects reported previously in rats. Regardless of treatment, Sertoli cells underwent only partial maturation in xenografts as Mullerian inhibiting substance and androgen receptor expression were lower than in donor and adult Tissue controls respectively. In conclusion, although treatments did not result in improvement of maturation of bovine Testis xenografts, the current study demonstrates that exogenous modulation of the endocrine milieu to affect xenograft development in recipient mice provides an accessible model to study endocrine control of spermatogenesis in large donor species.
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Germ cell transplantation and Testis Tissue xenografting in mice.
Journal of visualized experiments : JoVE, 2012Co-Authors: Lin Tang, Jose R. Rodriguez-sosa, Ina DobrinskiAbstract:Germ cell transplantation was developed by Dr. Ralph Brinster and colleagues at the University of Pennsylvania in 19941,2. These ground-breaking studies showed that microinjection of germ cells from fertile donor mice into the seminiferous tubules of infertile recipient mice results in donor-derived spermatogenesis and sperm production by the recipient animal2. The use of donor males carrying the bacterial β-galactosidase gene allowed identification of donor-derived spermatogenesis and transmission of the donor haplotype to the offspring by recipient animals1. Surprisingly, after transplantation into the lumen of the seminiferous tubules, transplanted germ cells were able to move from the luminal compartment to the basement membrane where spermatogonia are located3. It is generally accepted that only SSCs are able to colonize the niche and re-establish spermatogenesis in the recipient Testis. Therefore, germ cell transplantation provides a functional approach to study the stem cell niche in the Testis and to characterize putative spermatogonial stem cells. To date, germ cell transplantation is used to elucidate basic stem cell biology, to produce transgenic animals through genetic manipulation of germ cells prior to transplantation4,5, to study Sertoli cell-germ cell interaction6,7, SSC homing and colonization3,8, as well as SSC self-renewal and differentiation9,10. Germ cell transplantation is also feasible in large species11. In these, the main applications are preservation of fertility, dissemination of elite genetics in animal populations, and generation of transgenic animals as the study of spermatogenesis and SSC biology with this technique is logistically more difficult and expensive than in rodents. Transplantation of germ cells from large species into the seminiferous tubules of mice results in colonization of donor cells and spermatogonial expansion, but not in their full differentiation presumably due to incompatibility of the recipient somatic cell compartment with the germ cells from phylogenetically distant species12. An alternative approach is transplantation of germ cells from large species together with their surrounding somatic compartment. We first reported in 2002, that small fragments of Testis Tissue from immature males transplanted under the dorsal skin of immunodeficient mice are able to survive and undergo full development with the production of fertilization competent sperm13. Since then Testis Tissue xenografting has been shown to be successful in many species and emerged as a valuable alternative to study Testis development and spermatogenesis of large animals in mice14.
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Testis Tissue Xenografting
Fertility Preservation, 2011Co-Authors: Jose R. Rodriguez-sosa, Stefan Schlatt, Ina DobrinskiAbstract:Testis Tissue xenografting involves a series of procedures from donor Tissue preparation to graft recovery for analysis and/or sperm harvesting. In the current section, we describe these protocols in detail (modified from Dobrinski and Rathi [1]).
Rahul Rathi - One of the best experts on this subject based on the ideXlab platform.
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endocrine modulation of the recipient environment affects development of bovine Testis Tissue ectopically grafted in mice
Reproduction, 2012Co-Authors: Jose R Rodriguezsosa, Rahul Rathi, Guilherme Mj Costa, Luiz R Franca, Ina DobrinskiAbstract:Testis Tissue xenografting is a powerful approach for the study of Testis development and spermatogenesis, and for fertility preservation in immature individuals. In bovine Testis xenografts, maturation and spermatogenesis are inefficient when compared to other species. To evaluate if exogenous modulation of the endocrine milieu in recipient mice will affect spermatogenic efficiency in xenografts from newborn calves, recipient mice were treated with the GnRH antagonist acyline (5 mg/kg s.c. every 2 weeks) to reduce testosterone production in xenografts, or with 6-N-propyl-2-thiouracil (PTU, 0.1% in drinking water for 4 weeks), to induce transient hypothyroidism in recipient mice respectively. Both treatments altered developmental parameters of Testis xenografts and reduced germ cell differentiation. While the effects of acyline treatment can be attributed to inhibition of GnRH and gonadotropin action, lower Sertoli cell numbers and decreased seminiferous tubule length observed after PTU treatment were opposite to effects reported previously in rats. Regardless of treatment, Sertoli cells underwent only partial maturation in xenografts as Mullerian inhibiting substance and androgen receptor expression were lower than in donor and adult Tissue controls respectively. In conclusion, although treatments did not result in improvement of maturation of bovine Testis xenografts, the current study demonstrates that exogenous modulation of the endocrine milieu to affect xenograft development in recipient mice provides an accessible model to study endocrine control of spermatogenesis in large donor species.
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Development of Bovine Fetal Testis Tissue After Ectopic Xenografting in Mice
Journal of andrology, 2010Co-Authors: Jose R. Rodriguez-sosa, Rahul Rathi, Zhongde Wang, Ina DobrinskiAbstract:ABSTRACT: Testis Tissue xenografting represents a versatile model to study Testis biology, and to preserve fertility in immature animals. To evaluate whether bovine fetal testes can mature when grafted into mouse hosts, small fragments of testes from midgestation (125 to 145 days of gestation) bovine fetuses were grafted ectopically into immunodeficient castrated male mice. At grafting, donor Tissue displayed the typical seminiferous cords composed of gonocytes and primitive Sertoli cells. At 5 or 10 months after grafting, weight of the seminal vesicles in recipient mice was indicative of production of bioactive testosterone by xenografts. Xenografts showed similar development regardless of donor age. At 5 months, tubule formation occurred but germ cell differentiation had not proceeded beyond the spermatogonia stage. At 10 months, an increase in tubule size was evident and pachytene spermatocytes were observed as the most advanced type of germ cells in the xenografts of 2 donors. The number of tubules with germ cells was reduced in xenografts compared to donor Tissue, but at 10 months the number of germ cells per tubule was higher than in donors. Germ cell proliferation was similar in donor Tissue and xenografts. However, Sertoli cells showed a higher proliferation rate in xenografts collected at 5 months than in donor fetal testes and xenografts collected at 10 months. Sertoli cells in xenografts showed a progressive but incomplete loss of expression of Mullerian inhibiting substance and weak androgen receptor expression, indicating an incomplete Sertoli cell maturation. In conclusion, fetal Testis Tissue developed partially, qualitatively similar to pubertal testes in situ.
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Preservation and transplantation of porcine Testis Tissue
Reproduction fertility and development, 2009Co-Authors: Wenxian Zeng, Ali Honaramooz, Amy K. Snedaker, Susan Megee, Rahul Rathi, F. Chen, Ina DobrinskiAbstract:Grafting of immature mammalian Testis Tissue to mouse hosts can preserve the male germline. To make this approach applicable to a clinical or field situation, it is imperative that the Testis Tissue and/or spermatozoa harvested from grafted Tissue are preserved successfully. The aim of the present study was to evaluate protocols for the preservation of Testis Tissue in a porcine model. Testis Tissue was stored at 4°C for short-term preservation or cryopreserved by slow-freezing, automated slow-freezing or vitrification for long-term storage. Preserved Tissue was transplanted ectopically to mouse hosts and recovered xenografts were analysed histologically. In addition, spermatozoa were harvested from xenografts and cryopreserved. Total cell viability and germ cell viability remained high after Tissue preservation. Complete spermatogenesis occurred in xenografts preserved by cooling up to 48 h, whereas spermatogenesis progressed to round spermatids in the xenografts that were frozen–thawed before grafting. Approximately 50% of spermatozoa harvested from xenografts remained viable after freezing and thawing. The in vivo developmental potential of cryopreserved Tissue was reduced despite high post-thaw viability. Therefore, it is important to evaluate germ cell differentiation in vivo in addition to cell viability in vitro when optimising freezing protocols for Testis Tissue.
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Xenografting of sheep Testis Tissue and isolated cells as a model for preservation of genetic material from endangered ungulates.
Reproduction (Cambridge England), 2008Co-Authors: Lucía Arregui, Ali Honaramooz, Susan Megee, Rahul Rathi, Montserrat Gomendio, Eduardo R S Roldan, Ina DobrinskiAbstract:Recovery of germ cells could be an option for preservation of the genetic pool of endangered animals. In immature males, xenografting of Testis Tissue provides the opportunity to recover sperm from these animals. In adult animals, xenografting has been less successful, but de novo morphogenesis of functional Testis Tissue from dissociated Testis cells could be an alternative. To assess the potential use of these techniques in endangered bovid species, the domestic sheep was used as a model. Testes from 2-week-old lambs were grafted as Tissue fragments or cell suspensions into nude mice. Grafts were recovered at 4, 8, 12 and 16 weeks post grafting. For isolated cells, two additional time points at 35 and 40 weeks after grafting were added. In addition, to analyse the possible effect of social stress among mice within a group on the development of the grafts, Testis Tissue grafts were recovered 13 weeks post grafting from mice housed individually and in groups. Complete spermatogenesis occurred in sheep Testis xenografts at 12 weeks, similar to the situation in situ. Isolated sheep Testis cells were able to reorganize and form functional testicular Tissue de novo. Housing mice individually or in groups did not have any effect on the development of xenografts. Xenografting of Testis Tissue might be useful to obtain sperm from immature endangered ungulates that die prematurely. Testis Tissue de novo morphogenesis from isolated cells could open interesting options to recover germ cells from mature males with impaired spermatogenesis.
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Ectopic grafting of mammalian Testis Tissue into mouse hosts.
Methods in molecular biology (Clifton N.J.), 2008Co-Authors: Ina Dobrinski, Rahul RathiAbstract:Mammalian spermatogenesis is a highly organized process of cell division and differentiation that requires intimate contact between germ cells and testicular somatic cells. Lack of a suitable in vitro system has caused many aspects of spermatogenesis, especially in nonrodent species, to remain elusive. We describe ectopic grafting of Testis Tissue from sexually immature males to immunodeficient mouse hosts as an in vivo culture system that allows recapitulation of complete spermatogenesis from diverse mammalian species with the production of fertilization-competent sperm in a mouse host. In this system, the donor species testicular environment is preserved allowing experimentation in a small rodent. The accessibility of the Tissue in the mouse host makes it possible to manipulate spermatogenesis and steroidogenesis in a controlled manner that is often not feasible in the donor species. It also allows detailed analysis of the effects of toxins and compounds to enhance or suppress male fertility in an in vivo system without extensive experimentation in the target species. Finally, as it provides a source of male gametes even from immature gonads, grafting of fresh or preserved Testis Tissue offers an invaluable tool for the conservation of fertility in males if sperm cannot be obtained for cryopreservation.
Mohammad Amin Fayaz - One of the best experts on this subject based on the ideXlab platform.
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validation of ultrasound biomicroscopy for the assessment of xenogeneic Testis Tissue grafts and cell implants in recipient mice
Journal of Andrology, 2020Co-Authors: Mohammad Amin Fayaz, Jaswant Singh, Awang Hazmi Awangjunaidi, Ali HonaramoozAbstract:BACKGROUND Subcutaneous grafting/implantation of neonatal Testis Tissue/cells from diverse donor species into recipient mice can be used as an in vivo model to study Testis development, spermatogenesis, and steroidogenesis. Ultrasound biomicroscopy (UBM) allows obtaining high definition cross-sectional images of Tissues at microscopic resolutions. OBJECTIVES The present study was designed to (a) validate the use of UBM for non-invasive monitoring of grafts/implants overtime and to (b) correlate UBM findings with the morphological attributes of recovered grafts/implants. MATERIALS AND METHODS Testis Tissue fragments (~14 mm3 , each) and cell aggregates (100 × 106 cells, each) obtained from 1-week-old donor piglets (n = 30) were grafted/implanted under the back skin of immunodeficient mice (n = 6) in eight analogous sites per mouse. Three-dimensional transcutaneous Doppler UBM was performed, and a randomly selected graft and its corresponding implant were recovered at 2, 4, 6, and 8 weeks. RESULTS Graft/implant weight (P = .04) and physical height (P = .03) increased overtime. The dynamics of physical length and volume increases over time differed between Tissue grafts and cell implants (P = .02 and 0.01 for sample type*time interactions, respectively). UBM-estimated volume was correlated with the post-recovery weight and volume of the grafts/implants (r = 0.98 and r = 0.99, respectively; P < .001). Pre- and post-recovery length and height of the grafts/implants were positively and strongly correlated (r = 0.50, P = .01; r = 0.70, P = .001) and so were the areas covered by cordal, non-cordal, or fluid-filled cavities between UBM and histology (r = 0.87, P < .001). DISCUSSION AND CONCLUSION UBM findings correlated with physical attributes of the grafts/implants, validating its use as a non-invasive high-fidelity tool to quantify the developmental changes in ectopic Testis Tissue grafts and cell implants, potentially leading to a reduction in the number of recipient mice needed for similar experiments.
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Validation of ultrasound biomicroscopy for the assessment of xenogeneic Testis Tissue grafts and cell implants in recipient mice.
Andrology, 2020Co-Authors: Mohammad Amin Fayaz, Awang Hazmi Awang-junaidi, Jaswant Singh, Ali HonaramoozAbstract:BACKGROUND Subcutaneous grafting/implantation of neonatal Testis Tissue/cells from diverse donor species into recipient mice can be used as an in vivo model to study Testis development, spermatogenesis, and steroidogenesis. Ultrasound biomicroscopy (UBM) allows obtaining high definition cross-sectional images of Tissues at microscopic resolutions. OBJECTIVES The present study was designed to (a) validate the use of UBM for non-invasive monitoring of grafts/implants overtime and to (b) correlate UBM findings with the morphological attributes of recovered grafts/implants. MATERIALS AND METHODS Testis Tissue fragments (~14 mm3 , each) and cell aggregates (100 × 106 cells, each) obtained from 1-week-old donor piglets (n = 30) were grafted/implanted under the back skin of immunodeficient mice (n = 6) in eight analogous sites per mouse. Three-dimensional transcutaneous Doppler UBM was performed, and a randomly selected graft and its corresponding implant were recovered at 2, 4, 6, and 8 weeks. RESULTS Graft/implant weight (P = .04) and physical height (P = .03) increased overtime. The dynamics of physical length and volume increases over time differed between Tissue grafts and cell implants (P = .02 and 0.01 for sample type*time interactions, respectively). UBM-estimated volume was correlated with the post-recovery weight and volume of the grafts/implants (r = 0.98 and r = 0.99, respectively; P
Jaswant Singh - One of the best experts on this subject based on the ideXlab platform.
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Validation of ultrasound biomicroscopy for the assessment of xenogeneic Testis Tissue grafts and cell implants in recipient mice.
Andrology, 2020Co-Authors: Mohammad Amin Fayaz, Awang Hazmi Awang-junaidi, Jaswant Singh, Ali HonaramoozAbstract:BACKGROUND Subcutaneous grafting/implantation of neonatal Testis Tissue/cells from diverse donor species into recipient mice can be used as an in vivo model to study Testis development, spermatogenesis, and steroidogenesis. Ultrasound biomicroscopy (UBM) allows obtaining high definition cross-sectional images of Tissues at microscopic resolutions. OBJECTIVES The present study was designed to (a) validate the use of UBM for non-invasive monitoring of grafts/implants overtime and to (b) correlate UBM findings with the morphological attributes of recovered grafts/implants. MATERIALS AND METHODS Testis Tissue fragments (~14 mm3 , each) and cell aggregates (100 × 106 cells, each) obtained from 1-week-old donor piglets (n = 30) were grafted/implanted under the back skin of immunodeficient mice (n = 6) in eight analogous sites per mouse. Three-dimensional transcutaneous Doppler UBM was performed, and a randomly selected graft and its corresponding implant were recovered at 2, 4, 6, and 8 weeks. RESULTS Graft/implant weight (P = .04) and physical height (P = .03) increased overtime. The dynamics of physical length and volume increases over time differed between Tissue grafts and cell implants (P = .02 and 0.01 for sample type*time interactions, respectively). UBM-estimated volume was correlated with the post-recovery weight and volume of the grafts/implants (r = 0.98 and r = 0.99, respectively; P
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validation of ultrasound biomicroscopy for the assessment of xenogeneic Testis Tissue grafts and cell implants in recipient mice
Journal of Andrology, 2020Co-Authors: Mohammad Amin Fayaz, Jaswant Singh, Awang Hazmi Awangjunaidi, Ali HonaramoozAbstract:BACKGROUND Subcutaneous grafting/implantation of neonatal Testis Tissue/cells from diverse donor species into recipient mice can be used as an in vivo model to study Testis development, spermatogenesis, and steroidogenesis. Ultrasound biomicroscopy (UBM) allows obtaining high definition cross-sectional images of Tissues at microscopic resolutions. OBJECTIVES The present study was designed to (a) validate the use of UBM for non-invasive monitoring of grafts/implants overtime and to (b) correlate UBM findings with the morphological attributes of recovered grafts/implants. MATERIALS AND METHODS Testis Tissue fragments (~14 mm3 , each) and cell aggregates (100 × 106 cells, each) obtained from 1-week-old donor piglets (n = 30) were grafted/implanted under the back skin of immunodeficient mice (n = 6) in eight analogous sites per mouse. Three-dimensional transcutaneous Doppler UBM was performed, and a randomly selected graft and its corresponding implant were recovered at 2, 4, 6, and 8 weeks. RESULTS Graft/implant weight (P = .04) and physical height (P = .03) increased overtime. The dynamics of physical length and volume increases over time differed between Tissue grafts and cell implants (P = .02 and 0.01 for sample type*time interactions, respectively). UBM-estimated volume was correlated with the post-recovery weight and volume of the grafts/implants (r = 0.98 and r = 0.99, respectively; P < .001). Pre- and post-recovery length and height of the grafts/implants were positively and strongly correlated (r = 0.50, P = .01; r = 0.70, P = .001) and so were the areas covered by cordal, non-cordal, or fluid-filled cavities between UBM and histology (r = 0.87, P < .001). DISCUSSION AND CONCLUSION UBM findings correlated with physical attributes of the grafts/implants, validating its use as a non-invasive high-fidelity tool to quantify the developmental changes in ectopic Testis Tissue grafts and cell implants, potentially leading to a reduction in the number of recipient mice needed for similar experiments.
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Regeneration of Testis Tissue after ectopic implantation of porcine Testis cell aggregates in mice: improved consistency of outcomes and in situ monitoring
Reproduction fertility and development, 2020Co-Authors: Awang Hazmi Awang-junaidi, Jaswant Singh, Ali HonaramoozAbstract:Ectopic implantation of donor Testis cell aggregates in recipient mice results in de novo formation or regeneration of Testis Tissue and, as such, provides a unique invivo model for the study of Testis development. However, currently the results are inconsistent and the efficiency of the model remains low. This study was designed to: (1) examine several factors that can potentially improve the consistency and efficiency of this model and (2) explore the use of ultrasound biomicroscopy (UBM) for the non-invasive invivo evaluation of implants. Testis cell aggregates, containing ~40% gonocytes, from 1-week-old donor piglets were implanted under the back skin of immunodeficient mice through skin incisions using gel matrices or through subcutaneous injection without using gel matrices. The addition of gel matrices led to inconsistent Tissue development; gelatin had the greatest development, followed by collagen, whereas agarose resulted in poor development. The results also depended on the implanted cell numbers since implants with 100×106 cells were larger than those with 50×106 cells. The injection approach for cell implantation was less invasive and resulted in more consistent and efficient Testis Tissue development. UBM provided promising results as a means of non-invasive monitoring of implants.