Salivary lactoferrin is recognized by the human herpesvirus-8

J Invest Dermatol. 2005 Jun;124(6):1249-58. doi: 10.1111/j.0022-202X.2005.23756.x.

Abstract

Human herpesvirus-8 (HHV-8) is commonly detected in all epidemiologic forms of Kaposi's sarcoma. Despite the broad cellular tropism of HHV-8, studies on mucosal shedding of HHV-8 have shown that infectious particles are restricted to saliva isolated from the oropharynx. We used biotinylated purified HHV-8 particles in a direct binding assay to whole clarified human salivary samples isolated from HHV-8-infected and uninfected individuals. We found that the major binding activity was carried out by a protein of 78-kDa size, which was further characterized as human lactoferrin (hLf) using 2-D electrophoresis and MALDI-ToF analysis. Preliminary comparison of HHV-8 binding activity of 76 salivary samples from HHV-8-infected and uninfected individuals showed that 7.8% of the uninfected population exhibited a form of Lf not recognized by HHV-8. Deglycosylation of hLf by PNGase F did not reduce HHV-8 binding activity, whereas endoproteinase cleavage of native hLf generated a non-glycosylated 8-kDa peptide recognized by HHV-8 particles and was located at the position Ala606-Tyr679 in the native hLf amino acid sequence, corresponding to the C-terminal region of the glycoprotein. This work identify the lactoferrin in saliva as a ligand for HHV-8 and suggests that this glycoprotein could be used as a carrier for the viral particles.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Amino Acid Sequence
  • Case-Control Studies
  • Herpesviridae Infections / metabolism*
  • Herpesviridae Infections / virology*
  • Herpesvirus 8, Human / metabolism*
  • Humans
  • Lactoferrin / genetics
  • Lactoferrin / metabolism*
  • Ligands
  • Middle Aged
  • Molecular Sequence Data
  • Protein Structure, Tertiary
  • Saliva / metabolism*

Substances

  • Ligands
  • Lactoferrin