The efficiency of magnetic-activated cell sorting and fluorescence-activated cell sorting in the decontamination of testicular cell suspensions in cancer patients

Abstract

MACS and/or FACS are insufficient for completely depleting testicular tissue of malignant cells. Although more research on alternative decontamination techniques is necessary, developing a reliable method to screen a priori testicular tissue for malignant cells may be equally important.

Expression of stem cell markers: OCT4, KIT, ITGA6, and ITGB1 in the male germinal epithelium

“…Although several experiments enabled the purification of human SG using surface markers such as ITGA6 [Geens et al 2007;Geens et al 2011;Conrad et al 2008], GPR125 [He et al 2010], stage-specific embryonic antigen-4 (SSEA-4) [Izadyar et al 2011], and KIT [von Schonfeldt et al 1999]. Other studies have also shown that when these strategies are used they often yield a population of cells that are contaminated with cancer cells [Geens et al 2007;Geens et al 2011;Jahnukainen et al 2011].…”

“…Thus, the mass isolation of human stem spermatogonia (SG) in a safe way is not yet a feasible task [Goossens and Tournaye 2013]. Notwithstanding, several experiments enabled the purification of human SG using integrin alpha 6 (ITGA6) by using fluorescence-activated cell sorting (FACS) or magnetic-activated cell separation (MACS) [Geens et al 2007], MACS [Conrad et al 2008], or selection by selective matrix adhesion [Geens et al 2011]. The G protein-coupled receptor 125 (GPR125) [He et al 2010], the stage-specific embryonic antigen-4 (SSEA-4) [Izadyar et al 2011], and v-Kit Hardy-Zuckerman 4 Feline Sarcoma Viral Oncogene Homolog (KIT) [von Schonfeldt et al 1999] have also been successfully used for the isolation of human testicular stem SG by MACS.…”

“…The G protein-coupled receptor 125 (GPR125) [He et al 2010], the stage-specific embryonic antigen-4 (SSEA-4) [Izadyar et al 2011], and v-Kit Hardy-Zuckerman 4 Feline Sarcoma Viral Oncogene Homolog (KIT) [von Schonfeldt et al 1999] have also been successfully used for the isolation of human testicular stem SG by MACS. Studies have also demonstrated their contamination with cancer cells [Geens et al 2007;Geens et al 2011;Jahnukainen et al 2011]. This has hampered their use since a human threshold of contaminating malignant cells that can cause a relapse after transplantation to the testis is still unknown [Goossens and Tournaye 2013].…”

“…Cell purification with further differentiation in vitro could also contribute to the study of the molecular mechanisms that control SG proliferation, spermatocyte (ST) meiosis, and spermatid differentiation, as well as to develop better in vitro culture systems of cells involved in human spermatogenesis for male infertility treatments. The possible contamination of male germ cells with leukemic cells during auto transplantation programs constitutes an obstacle to the application of this technology to young cancer patients [Geens et al 2007;Geens et al 2011;Jahnukainen et al 2011]. To overcome this problem, the use of surface markers expressed exclusively in certain cell types might enable the positive selection of SG or the negative selection of leukemic cells, or to improve the performance of germ cell fraction purity.…”

The Next Frontier: The Promise of in vitro Spermatogenesis Coupled with Intracytoplasmic Sperm Injection

“…have described an innovative dual positive (CD90+) and negative (CD45-) selection strategy that uses fluorescence-activated cell sorting (FACS) to purify SSCs from a contaminated sample of nonhuman primate testis cells prior to transplantation [4]. Their findings are promising, especially when compared to previous studies that report less successful results in filtering out malignant cells prior to cell transplantation into recipient mouse testes [6,7]. In preparing a suitable filtering protocol for clinical applications, however, absolute certainty of removing all potential malignant cells prior to transplantation is unattainable, and the inherent risk such a procedure carries should be carefully considered.…”