Use of a novel washing method combining multiple density gradients and trypsin for removing human immunodeficiency virus-1 and hepatitis C virus from semen.

OBJECTIVE: To determine the effectiveness of a novel treatment designed to remove human immunodeficiency virus (HIV) -1 and hepatitis C virus (HCV) from spiked semen and to evaluate sperm motility and viability after treatment.
DESIGN: A prospective clinical laboratory-based study.
SETTING: The human studies were conducted in academic and national research environments. The bovine study was conducted in an accredited research facility. PATIENT(S): Healthy volunteers provided the semen samples used in the human studies; abattoir-derived material was used for the bovine embryo production study. INTERVENTIONS(S): None. MAIN OUTCOME MEASURE(S): Cytopathic, reverse transcriptase-polymerase chain reaction, and branched DNA assays were used to test the efficacy of the procedure for inactivating or removing viruses from spiked semen; standard semen evaluation criteria were used to assess the effects of the procedures on sperm motility and viability. RESULT(S): Trypsin exposure significantly reduced the infectivity of HIV-1. The triple density gradient treatment, with or without trypsin, had no detrimental affect on fresh or cryopreserved/thawed sperm 2-48 hours after treatment. The treatment of semen spiked with HIV-1 or HCV indicated that the procedure was effective for reducing viral copies to undetectable levels or below levels of clinical relevance. CONCLUSION(S): The procedure was effective for significantly inactivating or reducing HIV-1 and HCV in spiked semen without adversely affecting sperm quality.