Characterization and quantification of endogenous amyloid fibrils in human semen

• Applicant: Dr. Shariq Usmani
• Subject Area: Reproductive Medicine, Urology ; Virology
• Term: from 2013 to 2015
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 240832813

Previous studies involving screening of complex peptide libraries have shown that human semen contains a variety of amyloidogenic peptides derived from highly abundant precursors, such as prostatic acidic phosphatase and semenogelins. Under in vitro conditions these peptides form amyloid fibrils that potently enhance HIV-1 infection and have been the focus of intense research studies since they may be involved in HIV-1 transmission. It remained elusive, however, whether such amyloid fibrils do actually exist in human semen. Just recently, I was able to demonstrate that fibrils are indeed detectable in a significant proportion of semen samples. The goal of this pilot-project is to obtain insights into the quantity, formation, biophysical and HIV-enhancing properties of these naturally-occurring endogenous amyloid fibrils. This will be a key step towards a better understanding of the role of amyloid fibrils in HIV-1 transmission and semen physiology. Furthermore, my results will provide a solid basis for the development of novel strategies aiming to prevent the transmission of HIV/AIDS.

• DFG Programme: Research Grants