Sperm immobilization test and quantitative sperm immobilization test using frozen-thawed sperm preparation applied with computer-aided sperm analysis.

PURPOSE: In a previous study, a new method was described using the sperm immobilization test (SIT) with computer-aided sperm analysis (CASA). However, obtaining high-quality sperm as needed was a known issue. Here, we compared the results of using frozen-thawed sperm and fresh sperm for the SIT using the CASA method. METHODS: For the frozen-thawed preparation, 500 µL of condensed semen and 500 µL of Sperm Freeze were mixed in a cryovial and cryopreserved in liquid nitrogen. Density gradient centrifugation was used for the collection of motile sperm in both the fresh and frozen-thawed sperm preparations. A total of 50 serum samples were prepared for both the fresh and frozen-thawed sperm with each sample tested containing 10 µL of serum, 1 µL of either fresh or frozen motile sperm suspension, and 2 µL of complement. Sperm motilities were measured using CASA after a 1-hour incubation period for both fresh and frozen-thawed sperm. RESULTS: Both fresh and frozen-thawed sperm reacted similarly when exposed to serum containing sperm-immobilizing antibodies asserting the use of frozen-thawed sperm for the diagnosis of immunological infertility. CONCLUSION: These results suggest the possibility of using cryopreserved sperm for the SIT when fresh sperm is unavailable.

Application of computer-aided sperm analysis (CASA) for detecting sperm-immobilizing antibody.

PROBLEM: Since the 1970s, anti-sperm antibodies have been studied as a pathogenic factor contributing to infertility. The complement-dependent sperm-immobilization test (SIT) and quantitative SIT have been used as effective tools for detecting anti-sperm antibodies in clinical settings. These tests have been carried out traditionally by manually counting the number of motile sperm through eye estimation. METHOD OF STUDY: In this study, we developed a novel method using computer-aided sperm analysis. The results were compared with those obtained by the traditional method. RESULTS: The results were identical and 25 of 78 samples tested were positive and 53 samples were negative for sperm-immobilizing (SI) antibodies based on both methods. For SI-positive samples, the values of SI50 obtained using the two methods correlated closely with high co-efficiency. CONCLUSION: Using the novel method, manually counting the number of motile spermatozoa becomes unnecessary. The novel method presented here will increase the objectivity and convenience of using the SIT as a clinical indicator.

Mitochondrial DNA copy number in cumulus cells is a strong predictor of obtaining good-quality embryos after IVF.

PURPOSE: The aim of this study was to establish a simple tool to predict good-quality embryos in in vitro fertilization (IVF) by using cumulus cells (CCs) or peripheral blood cells (PBCs). METHODS: Mitochondrial DNA was extracted from CCs and PBCs in patients undergoing IVF. Using real-time polymerase chain reaction, mtDNA copy number in a single cell was calculated. Embryo quality was assessed when it was transferred or frozen. RESULTS: CCs were obtained from 60 oocyte cumulus-cell complexes (OCCCs) in 30 women, and PBCs were collected from 18 women. For the 30 women in the study, the median age was 37 years old (range, 24-43), and the mean body mass index was 21.4 (standard error, 2.0). mtDNA content of CCs and PBCs was highly correlated (Pearson's r = 0.900, p < 0.0001). The median mtDNA content of CCs for good- and poor-quality embryos was 140 and 57, respectively (p < 0.0001). The median mtDNA content of PBCs for good- and poor-quality embryos was 36 and 13, respectively (p = 0.604). The logistic regression model indicated that mtDNA content in CCs was the only parameter that predicted good-quality embryos (p = 0.020). The receiver operating characteristic curve for obtaining good-quality embryos by mtDNA copy number in CCs had an area under the curve of 0.823, and using a threshold of 86, positive and negative predictive values were 84.4 and 82.1 %, respectively. CONCLUSIONS: The determination of mtDNA content in CCs can be used to predict good-quality embryos.