Immunological and biochemical studies on fractionated bull spermatozoa

Human soluble antigens and their use in sperm antibody testing

Efforts were made to disrupt and solubilize human sperm cells and to evaluate the product for its content of infertility antibody-related antigens. In the procedure that was developed, a well-washed sperm sample is treated with 0.1 M dithiothreitol for 60 min, followed by trypsin at 0.1 mg/ml for 30 min, and then by soybean trypsin inhibitor. A mixture of DNAses I and II are added. After centrifuging, the resuspended pellet (RP) and the final supernatant (FS) show several degrees of cellular breakdown. Immunological evaluation was done with a strongly positive human serum containing sperm-head antibody. From the inhibition of sperm agglutination, we could conclude that the desired soluble antigen was obtained in the FS fraction.

Preparation of pure fractions of human sperm membranes

A procedure to isolate plasmalemma and outer acrosomal membranes from human spermatozoa provides reasonably purified fractions. Based on the shaking of samples in conditions that are not damaging for spermatozoa, this procedure excludes the use of chemical reagents or other chemicophysical methods harmful to sperm structure. The isolation of fractions is carried out by means of ultracentrifugation. The efficacy of the methodology has been verified by electron microscopy and by enzymological assays. The proposed method is easy to perform and gives good recoveries.

Extraction of human and rabbit acrosomes: a comparison of sequential and sonication methods

Two methods for the extraction of acrosomal membranes and enzymes from both human and rabbit spermatozoa were compared. Treatment of spermatozoa with hypotonic MgCl2 (0.05 M) solution causes removal of the plasma membrane, vesiculation, disruption and removal of the outer acrosomal membrane posterior to the equatorial segment with accompanying loss of soluble acrosomal material. Subsequent exposure to Hyamine 2389 and Triton X-100 removes acrosomal material bound to the inner acrosomal membrane with concomitant solubilization of this membrane. The MgCl2 extract from rabbit spermatozoa contained a higher yield of hyaluronidase, acrosin, and total proteinase activities, whereas the subsequent detergent extracts contained higher yields of both arylsulfatase A and B activities. By comparison, after 4 minutes of sonication to separate heads and tails, both rabbit and human spermatozoa when viewed by transmission electron microscopy showed alterations of plasma and outer acrosomal membranes with considerable loss of the acrosomal contents. Analysis of acrosomal enzymes indicates the greatest percentage of all the enzymes assayed was located in the extract obtained by sonication in contrast to either the separated head or tail fractions used for further subcellular extraction. Subsequent treatment with Hyamine and Triton yields only minimal amounts of enzyme activity.

The splitting of sperm heads from tails in eight mammalian species and the measurement of their sizes

Ejaculated spermatozoa from man, the Euopean wild boar and the bull, and spermatozoa from the cauda epididymes of the rabbit, rat, mouse, hamster and Guinea pig were treated with a sonic bath, a sonic probe, trypsin with and without prior treatment with a sulphhydryl reagent, pronase and alkalis. The fragments produced were counted and sized in an accurately calibrated Coulter Counter, Model ZB Industrial, before and after Zaponin treatment to lyse accompanying debris and the peripheral cytoplasm. Head and tail fractions were separated on sucrose gradients. Each species required different conditions for cleavage or fragmentation. Rabbit and bull spermatozoa were cleaved by the ultrasonic bath exactly into heads and tails, producing twice the number of particles with two peaks in the size distribution curves butith some 60% loss of total sperm volume which became the soluble fraction. The ultrasonic probe, and for the bull, pronase, produced the same cleavage but these more drastic treatments dissolved a considerable portion of the tail fraction. Rodent spermatozoa, especially the rat, were cleaved perfectly into heads and tails by mild trypsin treatment. All the nonrodent spermatozoa were resistent to trypsin cleavage, although prior treatment with a sulphhydryl reagent caused swelling and subsequent trypsin action caused digestion into miscellaneous pieces. Spermatozoa from the boar and from man could not be cleaved by any of the procedures. The sonic probe produced fragmentation with progressive dissolution of the tail fragments and a single peak in the size distribution curve corresponding to small stripped heads. The soluble fraction always constituted a large proportion of the original whole spermatozoa.