Isolation of human cationic antimicrobial protein-18 from seminal plasma and its association with prostasomes.
Author
Summary, in English
BACKGROUND: Cathelicidins are a group of antibiotic peptides with broad antimicrobial activity. They are considered to be an essential part of the innate immune system. The only known human cathelicidin is the human cationic antimicrobial protein (hCAP-18), from which the antimicrobial peptide LL-37 is released. METHODS AND RESULTS: In the present study, we purified hCAP-18 from seminal plasma and confirmed its identity by N-terminal amino acid sequencing. Gel filtration of seminal plasma showed the presence of hCAP-18 in both a low and a high molecular weight peak. Fractions corresponding to the high molecular form of hCAP-18 also contained dipeptidyl peptidase IV (CD26), a prostasome marker. This finding suggested that hCAP-18 found in fractions corresponding to high molecular weight molecules, is prostasome-associated. Flow cytometry confirmed the association of hCAP-18 with prostasomes and indicated that the molecule is surface bound. Western blot showed the presence of intact hCAP-18 in sperm, prostasomes and ultracentrifuged seminal plasma. CONCLUSIONS: These findings suggest that hCAP-18 may have an important role in antimicrobial defence during human reproduction. The binding of hCAP-18 to prostasomes indicates that protasomes can serve as a reservoir of this precursor of the antibiotic peptide LL-37.
Publishing year
2002
Language
English
Pages
34-2529
Publication/Series
Human Reproduction
Volume
17
Issue
10
Links
Document type
Journal article
Publisher
Oxford University Press
Topic
- Medicinal Chemistry
- Microbiology in the medical area
Keywords
- Antimicrobial Cationic Peptides/chemistry
- Blotting, Western
- Cathelicidins
- Cell Membrane/chemistry
- Chromatography, Gel
- Dipeptidyl Peptidase 4/analysis
- Epithelial Cells/chemistry
- Flow Cytometry
- Humans
- Male
- Molecular Weight
- Prostate/ultrastructure
- Semen/chemistry
- Sequence Analysis, Protein
- Spermatozoa/chemistry
- Ultracentrifugation
Status
Published
Research group
- Clinical Chemistry, Malmö
ISBN/ISSN/Other
- ISSN: 0268-1161