Variation of movement characteristics with washing and capacitation of spermatozoa. II. Multivariate statistical analysis and prediction of sperm penetrating ability

Can in vitro embryo production be estimated from semen variables in Senepol breed by using artificial intelligence?

Thoroughly analyzing the sperm and exploring the information obtained using artificial intelligence (AI) could be the key to improving fertility estimation. Artificial neural networks have already been applied to calculate zootechnical indices in animals and predict fertility in humans. This method of estimating the results of reproductive biotechnologies, such as in vitro embryo production (IVEP) in cattle, could be valuable for livestock production. This study was developed to model IVEP estimates in Senepol animals based on various sperm attributes, through retrospective data from 290 IVEP routines performed using 38 commercial doses of semen from Senepol bulls. All sperm samples that had undergone the same procedure during sperm selection for in vitro fertilization were evaluated using a computer-assisted sperm analysis (CASA) system to define sperm subpopulations. Sperm morphology was also analyzed in a wet preparation, and the integrity of the plasma and acrosomal membranes, mitochondrial potential, oxidative status, and chromatin resistance were evaluated using flow cytometry. A previous study identified three sperm subpopulations in such samples and the information used in tandem with other sperm quality variables to perform an AI analysis. AI analysis generated models that estimated IVEP based on the season, donor, percentage of viable oocytes, and 18 other sperm predictor variables. The accuracy of the results obtained for the three best AI models for predicting the IVEP was 90.7, 75.3, and 79.6%, respectively. Therefore, applying this AI technique would enable the estimation of high or low embryo production for individual bulls based on the sperm analysis information.

Ram Sperm Motility Parameters under The Influence of Epidermal Growth Factor

Epidermal growth factor (EGF) is one of the important cytokines that play a role in fertility. It is known that EGF affects both male and female reproduction, but its effect on sperm parameters is not fully understood. Up to the present, the effect of EGF on ram sperm motility parameters has not been published. We analyzed motility parameters of ejaculates after 24, 48, and 72 hours from the EGF addition. EGF was added to chilled ram sperm at concentrations of 0, 100, 200, and 400 ng·ml⁻¹. Analyses were realized using computer, assisted semen analyzer (CASA)—Hamilton Thorn motility analyzer (version 7). The effect of EGF was already visible after 30 min of incubation. Significant effect on ram sperm total motility and progressive movement was observed at higher EGF concentrations after 48 h of incubation. Our results show that EGF affects sperm motility parameters depending on concentration and time of exposure.

Prognostic value of objective semen parameters in an in vitro fertilization program

PURPOSE

The basic semen parameters seem to have a limited predictive value in male fertility. Could other objective sperm analyses be helpful in the choice of the most adapted assisted procreation technique?

METHODS

This study concerns 78 infertile couples with insemination failures. For each semen, 21 objective parameters are analyzed in fresh semen and after sperm selection procedure. The 78 couples are then included in an IVF protocol and classified into two groups: fertile (at least one cleaved embryo is obtained) and infertile.

RESULTS

Using multiple variant discriminant factorial analysis, we have found nine nonconventional parameters which induce us to define two classes of semen. These two classes fit with the classification into fertile and infertile groups in 74.4% of the cases.

CONCLUSIONS

So these parameters allow us to predict the chance of obtaining embryos during an IVF trial and to choose for each couple the most appropriate technique: IVF or ICSI.

A study of spermatozoal motility in type 1 diabetes mellitus

The aim of the study was to examine an aspect of male fertility in patients with Type 1 diabetes mellitus (n = 17) compared to healthy control subjects (n = 16) using parameters of sperm motility, measured using a computerized image analysis system (the Hamilton Thorn Research HTM-2030 Motility Analyzer), as indicators of potential fertility. Within the diabetic group no correlations were found between sperm motility and age, age of onset of diabetes, duration of diabetes or glycated haemoglobin. When the diabetic and control groups were compared, track speed, path velocity, progressive velocity, and lateral head displacement were not significantly different, whereas linearity and linear index, measures of straightness of swimming, were significantly greater in the diabetic subjects (59.2% vs 69.8%, p = 0.0005 and 76.4% vs 83.6%, p = 0.0016, respectively). We conclude that diabetic men, in the absence of complications, do not appear to be at a disadvantage in terms of sperm motility compared to healthy individuals.

A standardized test for visual analysis of human sperm morphology

OBJECTIVES

To develop a method to train and test simultaneously a large number of observers in the practice of visual sperm morphology analysis.

DESIGN

Photographs of fixed and stained sperm were prepared. Fields of suitable sperm images were selected and individual images were numbered on each negative. Two tests, which contained a total of 100 sperm images, were created. Thirty images in each test consisted of three repeats of 10 images, while 70 images in each test were unique. The tests were administered to individuals participating in an American Fertility Society postgraduate course. Sperm images were projected on a screen and participants classified each sperm using the method that was used in their own laboratory.

SETTING

Postgraduate course of The American Fertility Society.

RESULTS

The majority of individuals participating in the tests used some version of the World Health Organization method. The group using the Strict method reported a lower value for the percentage of normal sperm than the groups using the other methods. The variability for the percentage of normal sperm was highest for the Strict method. The degree of classification reversal, i.e., classifying a sperm as normal during one repeat and then reversing the classification during another repeat, was high for all groups (26% to 44% of the classifications). Some degree of improvement was seen from test 1 to test 2.

CONCLUSIONS

It is possible to develop efficient and inexpensive methods to train observers to perform the sperm morphology assay. Such methods also enable the objective measurement of the acquisition of proficiency, comparison between different classification methods, and identification of specific differences between observers. Such methods will become more important with implementation of the Clinical Laboratory Improvement Act.

Antigens in capacitated spermatozoa eliciting autoimmune responses

We studied the possible qualitative antigenic differences between native and capacitated spermatozoa pertaining to immunological infertility. Western blot analysis was used to test serum and seminal plasma immunoglobulin G (IgG) from 18 infertile couples with sperm antibodies, and 14 fertile men and 9 fertile women without significant sperm antibodies against native and capacitated spermatozoa from fertile and infertile men. More fertile and infertile subjects had serum and seminal plasma IgG binding to antigens with molecular weights of 34/36, 46, 68, 97, 105, 115, 120, 130, 150 and 190 kDa. in capacitated versus native spermatozoa of all men. Of the other hand, immune reactivity to antigens with molecular weight 22/24, 30, 32, 50, 80, 88/92 and 180 kDa. found in native autoimmune spermatozoa was strongest in infertile couples with sperm antibodies. This reactivity significantly increased against capacitated autoimmune spermatozoa. Native spermatozoa from few fertile men had these antigens but they appeared after capacitation. It seems that certain antigens normally appearing or enhanced after capacitation are already present in native spermatozoa from infertile men, probably due to an inherent aberration or premature capacitation. This might account for the observed enhanced immune responses in infertile couples to sperm antigens from infertile husbands.

Changes in sperm antibody test results when spermatozoa are subjected to capacitating conditions

Cytotoxic and immunobead-binding antibody assays were used to document possible changes in antigenicity after the spermatozoa were subjected in vitro to capacitating conditions. Serum and seminal plasma immunobead-binding immunoglobulin (Ig)A, sperm surface IgG, and IgA, and seminal plasma cytotoxic antibody titers in 26 autoimmune infertile men were decreased against autologous spermatozoa under capacitating conditions. Cytotoxic antibodies and immunobead-binding IgG, IgA, and IgM against husbands' sperm undergoing capacitation, in the cervical mucus of these women, were less than those against uncapacitated sperm. Conversely, sperm antibody levels were increased against the capacitated husbands' sperm in the husbands' serum and wives' cervical mucus, originally testing negative for cytotoxic antibodies against uncapacitated sperm. Antibody levels were unaltered against donors' sperm undergoing capacitation, except for a reduction in titers in the serum of isoimmune wives. The differences in sperm antibody assay results, depending on whether or not spermatozoa are incubated under conditions favoring capacitation, are specific to the husbands' and not to the donors' spermatozoal antigens.