title: The efficiency of magnetic-activated cell sorting and fluorescence-activated cell sorting in the decontamination of testicular cell suspensions in cancer patients.
abstract: BACKGROUND
  Before clinical application, the feasibility and safety of autologous testicular stem cell transplantation should be explored. Apart from limitations in their numbers, spermatogonial stem cells may also be contaminated by malignant cells. Therefore, both enrichment and decontamination before transplantation may be necessary. This study aimed at evaluating the decontaminating potential of magnetic-activated cell sorting (MACS) and/or fluorescence-activated cell sorting (FACS) for both murine and human testicular cell suspensions. In the mouse, the effectiveness of the transplantation technique after cell sorting was also assessed.
  
  
  METHODS
  Murine testicular cells were contaminated with 5% EL4 cells. Fresh and frozen-thawed suspensions were sorted using MACS (CD49f (+)) and FACS (CD49f(+), H-2Kb(-)) and evaluated by FACS, cell culture and transplantation into W/W(v) mice. Human testicular cells were contaminated with 5 or 0.05% CCRF-SB (SB) cells. Frozen-thawed suspensions were sorted using FACS (HLA class I(-)) and evaluated by FACS, cell culture and PCR for the B-cell receptor.
  
  
  RESULTS
  In the mouse, the sorted fractions contained 0.39% H-2K(b)-positive and 76.55% CD49f-positive cells. After transplantation, 1 in 20 recipient mice developed a malignancy. In the human experiments, an average of 0.58% SB cells was detected after sorting. In only 1 of 11 samples, there were no SB cells observed.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Research Centre for Reproduction and Genetics, University Hospital and Medical School, Vrije Universiteit Brussel, Belgium. mieke.geens@az.vub.ac.be
authors.forename: M
authors.initials: M
authors.lastname: Geens
authors.forename: H
authors.initials: H
authors.lastname: Van de Velde
authors.forename: G
authors.initials: G
authors.lastname: De Block
authors.forename: E
authors.initials: E
authors.lastname: Goossens
authors.forename: A
authors.initials: A
authors.lastname: Van Steirteghem
authors.forename: H
authors.initials: H
authors.lastname: Tournaye
mesh_terms: D000818:Animals; D002469:Cell Separation / Q000379:methods*; D002470:Cell Survival; D005434:Flow Cytometry / Q000379:methods*; D006801:Humans; D018189:Immunomagnetic Separation / Q000379:methods; D016399:Lymphoma, T-Cell / Q000473:pathology; D008280:Magnetics; D008297:Male; D051379:Mice; D009368:Neoplasm Transplantation; D009374:Neoplasms, Experimental / Q000473:pathology; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000473:pathology; D012680:Sensitivity and Specificity; D033581:Stem Cell Transplantation; D013737:Testis / Q000166:cytology*; D014407:Tumor Cells, Cultured