Abstract: A method of qualifying sperm cells is provided. The method comprising: (a) staining the sperm cells with acridine orange so as to obtain stained sperm cells; and (b) using a fluorescence activated cell sorter (FACS), gating events simultaneously stained with a green fluorescence intensity higher than 100 nm and red fluorescence intensity in a range selected from 20-1010 nm, the events representing a cell population of the stained sperm cells, wherein a percentage of the cell population is indicative of the quality of the sperm cells.

Abstract: A flow cytometry method and kit is provided for quantifying an absolute number of mature sperm cells in a semen sample, the method comprising (a) determining a total particle number (T); (b) determining a number of DNA comprising particles (D); (c) determining a number of cells which are not mature sperm cells (B) and; (d) determining a background signal (A); wherein steps (a) to (d) are not effected in a single aliquot of the semen sample, and whereas the number of mature sperm cells in the semen sample is equal to [(T×D)/100]?(A+B), thereby quantifying the absolute number of mature sperm cells in the semen sample.

Abstract: A flow cytometry method and kit is provided for quantifying an absolute number of mature sperm cells in a semen sample, the method comprising (a) determining a total particle number (T); (b) determining a number of DNA comprising particles (D); (c) determining a number of cells which are not mature sperm cells (B) and; (d) determining a background signal (A); wherein steps (a) to (d) are not effected in a single aliquot of the semen sample, and whereas the number of mature sperm cells in the semen sample is equal to [(T×D)/100]?(A+B), thereby quantifying the absolute number of mature sperm cells in the semen sample.