Elimination of HIV-1 from semen and application of the processed semen to assisted reproductive technology

As HIV infection is becoming a controllable chronic infection after the introduction of the highly active antiretroviral therapy (HAART), patients with this infection are now able to make plans for the future. Numerous serodiscordant (HIV-positive men and HIV-negative women) couples seek medical assistance to have a child with minimum risk to the HIV-negative female partner and the child using processed (washed) sperm. HIV-1 elimination from the semen using density gradient centrifugation and the swim-up procedure, which is a standard processing procedure, depends on both sperm motility and the physical properties of the virus-containing particles. To establish a simple method for recovering sperm from poor quality semen, we developed the tilted-tube rotation method to generate a continuous density gradient, and using this continuous density gradient we have succeeded in recovering motile sperm, even from the semen of seropositive males with severe male factors. This review aims to summarize the recent progress in the underlying principles and technical aspects of semen processing for elimination of HIV-1.