Spermagglutination by Bacteria.

Abstract

The agglutination of spermatozoa under the influence of different factors, such as acids, alkalis, salts of the heavy metals, CO₂, dyes, substances derived from ova, etc., was observed by various authors. By studying the action of bacteria on spermatozoa in vitro we discovered a new agglutinating factor in some strains of B. coli.

For our experiments we used: 1. A saline suspension of spermatozoa of guinea pigs, rats, and rabbits (epididymis specimens), and human (condom specimens). 2. A broth culture of B. coli or a saline emulsion of the bacterial growth from an agar slant. The test was performed on a glass slide by mixing a drop of the sperm-suspension with a drop of the culture. In a control drop of sperm without bacteria, the single spermatozoa were evenly distributed in the fluid. But after mixing with the bacteria, the spermatozoa were almost instantaneously agglutinated and formed flocculi and clumps which could easily be seen with the naked eye. Microscopic examination with low and high dry power showed that the spermatozoa were clumped together into big net-like formations. At the same time most of the spermatozoa were immobilized. A few of them, although included in the clumped net-work, were still slightly motile, but after a few minutes they lost all signs of motility. Spermatozoa mixed with B. coli culture in a tube formed clumps which in a short time settled down, leaving the supernatant fluid clear and transparent The reaction was irreversible. Addition of acids or alkalis, or shaking did not disintegrate the clumps. The agglutination by bacteria did not depend on the pH of the medium. The clumping under the influence of bacteria took place in solutions of various pH covering the range from 3 to 10.