Hamilton Thorne has received an increasing number of requests to add a low concentration level to its Accu-Beads+ QC test kit. In response, HT has added a third level of 3 M/ml, to the previous levels of 18 M/ml and 35 M/ml.
According to the WHO Laboratory Manual for the Examination of and Processing of Human Semen (5th edition), when an accurate assessment of low sperm numbers is not required for samples approximately 1 M/ml or lower, it is sufficient for most clinical purposes to report the sperm concentration as <2 M/ml (to take into account the high sampling error associated with low sperm numbers). Thus the 3 M/ml concentration is outside of the generalization range and may be used as a low level quality control for sperm counts.
Accu-Beads+ consist of three known concentrations of latex beads (3, 18 and 35 M/ml) suspended in an aqueous solution. Similar in size to human sperm, the Accu-Beads+ have been developed to confirm accurate counting procedures used for routine semen analysis.
Whether you perform your semen counts using an automated analyzer or manually, you can use Accu-Beads+ for quality control.
When used in an automated semen analyzer, the Accu-Beads+ test and evaluate the optical and image acquisition systems of the analyzer. For manual methods, the Accu-Beads+ are used to evaluate the actual counting procedures practiced. Because motility is irrelevant for checking these functions, the static nature of the Accu-Beads+ will not affect the quality control testing.
Using a pipette, simply draw the required amount (undiluted) and load your standard semen analysis chamber, such as a disposable fixed-depth slide (eg Leja, 2X-CEL) or a Petroff-Hausser, Makler, or Hemacytometer chamber. Position the chamber on the stage of the microscope or analyzer and perform an analysis according to your normal procedure.
The images below show the three Accu-Beads+ concentrations as analyzed on the CASA II software.
Accu-Beads+ are packaged in 5 ml aliquots and are stable at room temperature for up to 2 years. Complete instructions for use with the Hamilton Thorne automated analyzers and for manual counting methods are included with each package.