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The Surprising Role of Amyloid Fibrils in HIV Infection

Laura M Castellano1, James Shorter2

  • 1Pharmacology Graduate Group, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA. lcast@mail.med.upenn.edu.

Biology
|May 17, 2014
PubMed

Insights

Semen-derived amyloid fibrils significantly enhance HIV transmission by promoting viral attachment. Reversing fibril formation offers a novel preventative strategy against sexual HIV infection.

Area of Science:

  • Virology
  • Biochemistry
  • Public Health

Background:

  • Human immunodeficiency virus (HIV) remains a global health threat.
  • Semen contains amyloidogenic peptides that form fibrils, enhancing HIV infectivity.
  • These fibrils, like SEVI (Semen derived Enhancer of Viral Infection), potentiate infection by facilitating virion attachment and fusion.

Purpose of the Study:

  • To review the identification and mechanisms of amyloidogenic peptides in semen that enhance HIV infection.
  • To explore strategies for inhibiting the HIV-enhancing effects of these peptide fibrils.
  • To highlight the potential of targeting host-encoded protein conformers as a preventative approach.

Main Methods:

  • Review of scientific literature on semen-derived amyloid fibrils and their role in HIV transmission.
  • Analysis of the mechanism by which fibrils enhance viral infectivity.
  • Discussion of various strategies aimed at inhibiting fibril formation or reversing existing fibrils.

Main Results:

  • Amyloid fibrils formed by semen peptides (e.g., PAP248-286, PAP85-120, SEM1, SEM2) significantly increase HIV infectivity, particularly at low viral titers.
  • Fibril-mediated enhancement of infectivity occurs through facilitation of virion attachment and fusion to target cells.
  • Soluble peptides do not exhibit the same infectivity-enhancing effects as their fibrillar forms.

Conclusions:

  • Amyloid fibrils in semen represent a significant factor in sexual HIV transmission.
  • Developing methods to reverse fibril formation is a promising, innovative preventative strategy.
  • Targeting host-derived amyloidogenic peptides offers a complementary approach to traditional antiviral therapies.

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