Cytoskeletal organization defects and abortive activation in human oocytes after IVF and ICSI failure

• Published in: Molecular human reproduction Vol. 6; no. 6; pp. 510 - 516
• Main Authors: Rawe, V.Y., Olmedo, S.Brugo, Nodar, F.N., Doncel, G.D., Acosta, A.A., Vitullo, A.D.
• Format: Journal Article
• Language: English
• Published: Oxford Oxford University Press 01.06.2000; Oxford Publishing Limited (England)
• Subjects: abortive activation; Biological and medical sciences; Cell structures and functions; Chromatin - ultrastructure; Chromosomes - physiology; cytoskeletal organization; Cytoskeleton - metabolism; Cytoskeleton - ultrastructure; Cytoskeleton, cytoplasm. Intracellular movements; DNA - ultrastructure; Female; fertilization failure; Fertilization in Vitro; Fundamental and applied biological sciences. Psychology; Humans; Male; Metaphase; microtubules; Microtubules - metabolism; Microtubules - ultrastructure; Mitosis; Molecular and cellular biology; Oocytes - metabolism; Oocytes - ultrastructure; Sperm Injections, Intracytoplasmic; Spermatozoa - physiology; Spermatozoa - ultrastructure; Spindle Apparatus - metabolism; Spindle Apparatus - ultrastructure; Treatment Failure; Tubulin - metabolism; Human; Pregnancy disorders; Intracytoplasmic sperm injection; Assisted procreation; Activation; Germinal cell; Abortion; Pronucleus; In vitro fertilization embryo transfer; Polar body; Tubulin; Cytogenetics; Cytoskeleton; Female; Microtubule; Immunofluorescence; Oocyte
• ISSN: 1360-9947; 1460-2407; 1460-2407
• DOI: 10.1093/molehr/6.6.510

In this study, we analysed the distribution of β tubulins to detect spindle and cytoplasmic microtubules, α acetylated tubulins for sperm microtubules and chromatin configuration in oocytes showing fertilization failure after conventional IVF or intracytoplasmic sperm injection (ICSI). A total of 450 human oocytes that failed to fertilize were studied 20–40 h after IVF or ICSI. In all, 287 oocytes were stained for immunofluorescence and chromosomal spreads were performed by Tarkowski's air-drying method in 163 IVF or ICSI oocytes that did not develop pronuclei after the extrusion of a second polar body. Immunofluorescence analysis showed that the main reason of fertilization failure after IVF was no sperm penetration (55.5%). The remaining oocytes showed different abnormal patterns, e.g. oocyte activation failure (15.1%) and defects in pronuclei apposition (19.2%). On the other hand, fertilization failure after ICSI was mainly associated to incomplete oocyte activation (39.9%), and to a lesser extent with defects in pronuclei apposition (22.6%) and failure of sperm penetration (13.3%). A further 13.3% of the ICSI oocytes arrested their development at the metaphase of the first mitotic division. The chromosomal spreads allowed the analysis of abortive activations, in which no pronuclei formed but a second polar body was extruded. Immunofluorescence and cytogenetic analysis provided a useful tool to improve infertility diagnosis and prognosis in each particular case.