Ectopic porcine spermatogenesis in murine subcutis: tissue grafting versus cell-injection methods

Abstract

Fragments of testis tissue from immature animals grow and develop spermatogenesis when grafted onto subcutaneous areas of immunodeficient mice. The same results are obtained when dissociated cells from immature testes of rodents are injected into the subcutis of nude mice. Those cells reconstitute seminiferous tubules and facilitate spermatogenesis. We compared these two methods, tissue grafting and cell-injection methods, in terms of the efficiency of spermatogenesis in the backs of three strains of immunodeficient mice, using neonatal porcine testicular tissues and cells as donor material. Nude, severe combined immunodeficient (SCID) and NOD/Shi-SCID, IL-2Rγ c null (NOG) mice were used as recipients. At 10 months after surgery, the transplants were examined histologically. Both grafting and cell-injection methods resulted in porcine spermatogenesis on the backs of recipient mice; the percentage of spermatids present in the transplants was 67% and 22%, respectively. Using the grafting method, all three strains of mice supported the same extent of spermatogenesis. As for the cellinjection method, although SCID mice were the best host for supporting reconstitution and spermatogenesis, any difference from the other strains was not significant. As NOG mice did not show any better results, the severity of immunodeficiency seemed to be irrelevant for supporting xeno-ectopic spermatogenesis. Our results confirmed that tubular reconstitution is applicable to porcine testicular cells. This method as well as the grafting method would be useful for studying spermatogenesis in different kinds of animals.

De novo morphogenesis of testis tissue: an improved bioassay to investigate the role of VEGF165 during testis formation

“…We concluded that addition of Matrigel to the mixture enhances tubule formation and decreases the requirement for large numbers of donor cells, which is beneficial for future studies in animal models where the availability of donor tissue may be limited. The positive influence of Matrigel on the development of tissue from a smaller number of testicular cells is in accordance to what has been reported (Kita et al 2007, Watanabe et al 2009). Similarly, this matrix has been used to support tumor growth or maintenance of pancreatic islets in xenogenic hosts (Ruggeri et al 2002, Dufour et al 2005).…”

“…The influence of number of cells grafted was determined comparing tubule formation when the same conditions were provided to different number of cells grafted; our results supported what has been previously hypothesized (Watanabe et al 2009), that the number of cells grafted are correlated with tubule formation.…”

Efficient generation of functional haploid spermatids from human germline stem cells by three-dimensional-induced system

“…As basement membrane components seem to be physiologically appropriate for the 3D culture of testicular cells, matrigel matrix provides a 3D environment for germ cell differentiation. Previous studies have indicated that spermatogenic efficiency and testis tubule formation can be improved by the addition of matrigel [ 37 – 39 ]. Therefore, matrigel matrix was selected in this study.…”

Effects of recipient mouse strain, sex and gonadal status on the outcome of testis tissue xenografting

“…It has been suggested that a higher severity of immunodeficiency in recipients may provide a more suitable host environment for the development of xenografts (Ito et al 2002). In a few studies, severe combined immunodeficient (SCID) mice, which lack both T and B lymphocytes, have been used successfully in testis tissue xenografting with no obvious changes in the outcomes (Rathi et al 2005(Rathi et al , 2006Geens et al 2006;Goossens et al 2008;Watanabe et al 2009).…”