Failure of oocyte activation after intracytoplasmic sperm injection using round-headed sperm

Boar spermatozoa were prepared for intracytoplasmic sperm injection (ICSI) by two different treatments to facilitate sperm chromatin decondensation and improve fertilisation rates after ICSI in pigs: spermatozoa were either frozen and thawed without cryoprotectants, or treated with progesterone. Morphological changes of the sperm heads after the treatments were examined and then the activation of oocytes and the transformation of the sperm nucleus following ICSI were assessed. After freezing and thawing, the plasma membrane and acrosomal contents over the apical region of sperm head were lost in all the spermatozoa. Following treatment with 1 mg/ml progesterone, the acrosome reaction was induced in 61% of spermatozoa. After injection of three types of spermatozoa, non-treated spermatozoa and progesterone-treated (i.e. acrosome-reacted) spermatozoa induced oocyte activation, but frozen-thawed spermatozoa induced oocyte activation at a significantly lower rate. Sixty-two per cent of sperm heads remained orcein-negative for 6 h, however, resulting in delayed sperm chromatin decondensation and low male pronuclear formation in the oocytes injected with a non-treated spermatazoon. Since the treatments of freezing and thawing and progesterone for spermatozoa accelerated the initial change in sperm chromatin and the latter treatment induced oocyte activation earlier, it is considered that the delay in oocyte activation and decondensation of sperm chromatin after injection of non-treated spermatozoa is caused by the existence of the sperm plasma membrane. These results show that progesterone treatment efficiently induces the acrosome reaction in boar spermatozoa without destroying their potency for oocyte activation, and the induction of the acrosome reaction results in the promotion of male pronuclear formation after ICSI.

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Effect of artificial oocyte activation in intracytoplasmic sperm injection using testicular spermatozoa on sibling oocytes

Fertility and Sterility ◽

10.1016/j.fertnstert.2015.07.993 ◽

2015 ◽

Vol 104 (3) ◽

pp. e317

Author(s):

C. Takahashi ◽

S. Mizuta ◽

R. Nishiyama ◽

K. Yamaguchi ◽

K. Kitaya ◽

...

Keyword(s):

Intracytoplasmic Sperm Injection ◽

Oocyte Activation ◽

Sibling Oocytes ◽

Testicular Spermatozoa ◽

Artificial Oocyte Activation

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Experiences with intracytoplasmic sperm injection

Reproductive Medicine Review ◽

10.1017/s0962279900001083 ◽

1995 ◽

Vol 4 (2) ◽

pp. 75-86 ◽

Cited By ~ 4

Author(s):

Susan E Lanzendorf

Keyword(s):

Intracytoplasmic Sperm Injection ◽

Meiotic Division ◽

Reproductive Tract ◽

Female Reproductive Tract ◽

Oocyte Activation ◽

Fertilization Failure ◽

Cortical Granules ◽

Specific Sequence ◽

Mammalian Fertilization ◽

Pass Through

Mammalian fertilization, whether it takes place within the female reproductive tract or within a laboratory dish, is comprised of many processes which must follow a specific sequence. The spermatozoon must bind to and pass through the zona pellucida, fuse with the oolemma and become incorporated into the cytoplasm of the oocyte. Fusion of the two gametes triggers oocyte activation, resulting in exocytosis of the cortical granules and completion of the second meiotic division of the oocyte. A block in one or more of these processes, due either to abnormalities in the spermatozoon or oocyte, may result in fertilization failure.

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Different activation treatments for successful development of bovine oocytes following intracytoplasmic sperm injection

Zygote ◽

10.1017/s0967199403001096 ◽

2003 ◽

Vol 11 (1) ◽

pp. 69-76 ◽

Cited By ~ 21

Author(s):

S.A. Ock ◽

J.S. Bhak ◽

S. Balasubramanian ◽

H.J. Lee ◽

S.Y. Choe ◽

...

Keyword(s):

Intracytoplasmic Sperm Injection ◽

Chromosomal Abnormality ◽

Polar Body ◽

Ultrastructural Changes ◽

Time Interval ◽

Oocyte Activation ◽

Group 4 ◽

Group 5 ◽

Bovine Oocytes

In this study, the developmental capacity and cytogenetic composition of different oocyte activation protocols was evaluated following intracytoplasmic sperm injection (ICSI) of in vitro matured bovine oocytes. Motile spermatozoa selected by Percoll density gradient were treated with 5 mM dithiothreitol (DTT) and analysed for ultrastructural changes of the head using transmission electron microscopy (TEM). The alterations in sperm morphology after DTT treatment for different times (15, 30 and 60 min) were 10%, 45-55% and 70-85%, respectively. Further, a partial decondensation of sperm heads was observed after DTT treatment for 30 min. Oocytes were injected with sperm treated with DTT for 30 min. In group 1, sperm injection was performed without any activation stimulus to the oocytes. In group 2, sham injection without sperm was performed without activating the oocytes. Oocytes injected with sperm exposed to 5 μM ionomycin for 5 min (group 3), 5 μM ionomycin + 1.9 mM dimethylaminopurine (DMAP) for 3 h (group 4) and 5 µM ionomycin + 3 h culture in M199 + 1.9 mM DMAP (group 5) were also evaluated for cleavage, development and chromosomal abnormality. Cleavage and development rates in groups 1, 2 and 3 were significantly (p < 0.05) lower than those in groups 4 and 5. The incidence of chromosomal abnormality in the embryos treated directly with DMAP after ionomycin (group 4) was higher than in group 5. We conclude that immediate DMAP treatment after ionomycin exposure of oocytes results in arrest of release of the second polar body, and thus leads to changes in chromosomal pattern. Therefore, the time interval between ionomycin and DMAP plays a crucial role in bovine ICSI.

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Risk of birth defects in children conceived by artificial oocyte activation and intracytoplasmic sperm injection: a meta-analysis

Reproductive Biology and Endocrinology ◽

10.1186/s12958-020-00680-2 ◽

2020 ◽

Vol 18 (1) ◽

Author(s):

Rui Long ◽

Meng Wang ◽

Qi Yu Yang ◽

Shi Qiao Hu ◽

Li Xia Zhu ◽

...

Keyword(s):

Birth Defects ◽

Chromosomal Aberrations ◽

Intracytoplasmic Sperm Injection ◽

Safety Concern ◽

Final Analysis ◽

Oocyte Activation ◽

Patient Counseling ◽

China National Knowledge Infrastructure ◽

Significant Difference ◽

Artificial Oocyte Activation

Abstract Background Whether artificial oocyte activation (ICSI-AOA) will increase the risk of birth defects remains controversial. Thus, we performed this study to evaluate the risk of birth defects and further compare the incidence of different birth defects types (chromosomal aberrations and non-chromosomal aberrations) in children conceived by ICSI-AOA and conventional intracytoplasmic sperm injection (ICSI) in an enlarged sample size. Method A comprehensive review of the literatures comparing birth defects in children conceived by ICSI-AOA and conventional ICSI by October 2020 was performed in PubMed, Embase, Cochrane Libraries, Web of Science, and Chinese databases including China National Knowledge Infrastructure, China Biology Medicine disc and Wan Fang. Risk ratios (RR) and 95% confidence intervals (CI) were calculated. Results Five studies were included in the final analysis. Compared with conventional ICSI, ICSI-AOA did not increase the birth defects rate (RR = 1.27, 95%CI 0.70–2.28) of children. Furthermore, in a subgroup analysis, birth defects were classified into two types (chromosomal aberrations and non-chromosomal aberrations) in four studies and no statistical difference were revealed. Conclusion Our analysis indicates that ICSI-AOA represents no significant difference in the prevalence of major birth defects or types of birth defects (chromosomal aberrations and non-chromosomal aberrations) comparing with conventional ICSI. This conclusion may provide clinicians evidence-based support in patient counseling and instruction of the application and safety concern about ICSI-AOA.

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