Evidence of modified nuclear protein matrix in human spermatozoa with fragmented deoxyribonucleic acid  Rebeca Santiso, Ph.D., Lourdes Muriel, Ph.D., Vicente Goyanes, M.D., Enrique Segrelles, M.D., Jaime Gosálvez, Ph.D., José Luis Fernández, M.D.  Fertility and Sterility  Volume 87, Issue 1, Pages 191-194 (January 2007) DOI: 10.1016/j.fertnstert.2006.05.055 Copyright © 2007 American Society for Reproductive Medicine Terms and Conditions

Figure 1 Human sperm cells treated in microgel with a lysing solution with SDS (A–C) or without SDS (D–F). (A, D): DNA staining with DAPI (blue). (B, E): Protein staining with mercuridibromfluorescein (green). (C, F): Merge of A and B, and D and E, respectively. Staining with DAPI (A, D) shows that spermatozoa without DNA fragmentation produce halos of relaxation of DNA loops, whereas those with fragmented DNA result in big halos of diffusion of DNA fragments. Protein staining after lysing with the strong SDS-containing solution (B) shows remnant residual aggregated nuclear matrix proteins only in sperm cells with fragmented DNA. When using a softer lysing solution (E), sperm tails remain, and all spermatozoa show residual nuclear matrix proteins. Nevertheless, whereas residual matrices appear faint and homogeneous in sperm without DNA fragmentation, they are dense and aggregated in sperm with fragmented DNA. (G–I): Human granulocytes from peripheral blood treated with the lysing solution without SDS. The apoptotic cell with diffused fragmented DNA (G), retains a condensed and collapsed residual nuclear matrix (H), unlike those cells without fragmented DNA. (I): Merge of G and H. Santis. Nuclear protein matrix in sperm with fragmented DNA. Fertil Steril 2007. Fertility and Sterility 2007 87, 191-194DOI: (10.1016/j.fertnstert.2006.05.055) Copyright © 2007 American Society for Reproductive Medicine Terms and Conditions